Updated on 2023/04/22

写真a

 
NISHIHORI Masahiro
 
Organization
Nagoya University Hospital Neurosurgery Assistant professor of hospital
Title
Assistant professor of hospital
Contact information
メールアドレス
External link

Degree 1

  1. Ph.D. ( 2021.9   Nagoya University ) 

Research Interests 12

  1. 脳動脈瘤

  2. 硬膜動静脈瘻

  3. 医用画像処理

  4. 脳血管内治療

  5. carotid stenosis

  6. 脳血管内治療

  7. 脳卒中の外科

  8. stroke

  9. brain AVM

  10. brain aneurysm

  11. dural AVF

  12. mechanical thrombectomy

Research Areas 2

  1. Life Science / Neurosurgery

  2. Life Science / Neurosurgery

Research History 2

  1. Nagoya University   Nagoya University Hospital Neurosurgery   Assistant professor of hospital

    2016.3

  2. Nagoya University   Nagoya University Hospital Neurosurgery   Assistant professor of hospital

    2016.3

Education 2

  1. Nagoya University

    2013.4 - 2016.2

      More details

    Country: Japan

  2. Nagoya University   Faculty of Medicine

    2002.4 - 2008.3

      More details

    Country: Japan

Professional Memberships 12

  1. 日本脳神経外科学会

  2. 日本脳神経血管内治療学会

  3. 日本脳卒中学会

  4. 日本脳卒中の外科学会

  5. 日本脳神経CI学会

  6. 日本脳神経外科コングレス

  7. 日本脳神経血管内治療学会

  8. 日本脳神経外科学会

  9. 日本脳神経外科コングレス

  10. 日本脳神経CI学会

  11. 日本脳卒中学会

  12. 日本脳卒中の外科学会

▼display all

Committee Memberships 7

  1. Stroke2023   program member  

    2022.4   

      More details

    Committee type:Academic society

  2. 第38回NPO法人日本脳神経血管内治療学会学術集会   プログラム委員  

    2022.1 - 2022.11   

      More details

    Committee type:Academic society

  3. CSNET   secretary-general  

    2021.12   

      More details

    Committee type:Academic society

  4. STROKE 2022   program member  

    2021.2 - 2022.1   

      More details

    Committee type:Academic society

  5. 第46回日本脳卒中学会学術集会   査読委員  

    2020.10 - 2021.2   

      More details

    Committee type:Academic society

  6. Japan Stroke Society   councilor  

    2020.8 - 2022.7   

      More details

    Committee type:Academic society

  7. 日本脳神経外科学会 第76回総会   プログラム委員  

    2016.10 - 2017.10   

      More details

    Committee type:Academic society

▼display all

 

Papers 71

  1. Rare Dilated Collateral Circulation from Accessory Meningeal Artery to Inferolateral Trunk: A Case Report

    IKEZAWA Mizuka, MAEDA Kenko, TAKASU Syuntaro, TAKEMOTO Masaya, NISHIHORI Masahiro, CHOO Jungsu, SAGO Fumihiro, SOMIYA Daiki, DOBA Kohei, IKEDA Akira

    NMC Case Report Journal   Vol. 10 ( 0 ) page: 47 - 50   2023.12

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>The accessory meningeal artery (AMA) demonstrates various potential anastomoses with the external (ECA) and internal (ICA) carotid arteries. However, rarely does the AMA markedly dilate and compensate for ICA blood flow. A 52-year-old woman with nonspecific symptoms was diagnosed with multiple cerebral aneurysms and abnormal blood vessels observed on magnetic resonance angiography. Digital subtraction angiography revealed four aneurysms and anastomoses between the left AMA and inferolateral trunk (ILT). In addition, two sequential severe flexions were observed in the cervical portion of the left ICA. No ischemic lesions were detected on magnetic resonance imaging. In conclusion, we experienced a rare case in which the AMA-ILT anastomosis was highly developed. This case also presented with the unusual characteristics of an anomaly in the extracranial ICA and multiple aneurysms.</p>

    DOI: 10.2176/jns-nmc.2022-0308

    CiNii Research

  2. Butterfly needle tap and suction (BTS) technique: a treatment for recurrent chronic subdural hematoma after burr hole craniostomy

    Yamamoto Shun, Nagashima Yoshitaka, Maki Hideki, Nishimura Yusuke, Araki Yoshio, Nishihori Masahiro, Noda Tomoyuki, Imai Tasuku, Kawabata Teppei, Ueno Masahiro, Nishida Yasumasa, Saito Ryuta

    ACTA NEUROCHIRURGICA   Vol. 165 ( 4 ) page: 841 - 848   2023.4

     More details

    Language:English   Publisher:Acta Neurochirurgica  

    Background: In this study, we propose a butterfly needle tap and suction (BTS) technique for recurrent chronic subdural hematoma (CSDH) as an alternative to reoperation with burr hole craniostomy (BHC) and investigate its efficacy and safety. The procedure involves percutaneous puncture through the burr hole created during the previous surgery and subsequent hematoma evacuation using a butterfly needle. Methods: This retrospective study included patients who underwent BTS for CSDH at Ogaki Municipal Hospital between January 2017 and December 2020. The follow-up CT scans were reviewed after several weeks. We evaluated the number of percutaneous punctures required to resolve CSDH during the BTS technique, the volume of the evacuated hematoma, and procedure-related complications. Results: Twenty-six patients were enrolled in the study, 21 of whom achieved resolution of the hematoma using punctures with the BTS technique alone (mean, 2.2 ± 1.5). Five patients had a recurrence of hematoma after one or more punctures during the BTS technique, and they underwent reoperation with BHC according to the surgeon’s decision or patient requests. Among the 55 punctures, 43.0 ± 16.0 ml of hematoma was evacuated per puncture. The evacuated hematoma volume was 41.9 ± 16.4 ml in the BTS-alone group and 49.4 ± 12.9 ml in the reoperation group, with no significant difference (p = 0.25). Three patients complained of a headache during the puncture procedure, and no other complications, including intracranial hemorrhage or infection, were reported therein. Conclusions: The BTS technique is an effective alternative to reoperation with BHC.

    DOI: 10.1007/s00701-023-05543-4

    Web of Science

    Scopus

    PubMed

  3. Antiplatelet therapy discontinuation after stent-assisted coil embolization for intracranial aneurysms: a single-center, long-term, retrospective, observational study

    Goto S., Izumi T., Nishihori M., Imai T., Araki Y., Kanamori F., Uda K., Yokoyama K., Saito R.

    Journal of Neurosurgery   Vol. 138 ( 3 ) page: 724 - 731   2023.3

     More details

    Publisher:Journal of Neurosurgery  

    OBJECTIVE The protocol for antiplatelet therapy after stent-assisted coil embolization (SACE) for intracranial aneurysms is not well established. In particular, the indications for single antiplatelet therapy (SAPT) discontinuation remain controversial. The authors investigated the long-term outcomes of SAPT discontinuation after SACE among patients at a single institution. METHODS Patients who underwent SACE during the period from 2010 to 2020 and who were followed up for > 1 year were included in this study. The delayed ischemic and hemorrhagic complication rates were examined during follow-up. Moreover, the risk factors of antiplatelet therapy reduction or discontinuation and the outcomes of SAPT discontinuation were examined. RESULTS In total, 240 patients were included in the analysis. The average patient age was 60.3 years, and the average follow-up period was 46.7 months. Nine (3.8%) patients presented with symptomatic delayed ischemic complication, and 3 (1.3%) patients experienced a decline in modified Rankin Scale score. The stent configuration (T- or Y-stent) was the only risk factor associated with delayed ischemic complication (p < 0.001). SAPT was discontinued in 147 (71.7%) of 205 patients who were followed up for > 2 years, and no ischemic complications were observed. CONCLUSIONS It is safe to discontinue SAPT in patients without ischemic complications and with stable intraaneurysmal signals on MRA 2 years after SACE. The T- or Y-stent is a high-risk factor for delayed ischemic complications, and antiplatelet therapy reduction or discontinuation should be cautiously considered.

    DOI: 10.3171/2022.6.JNS22815

    Scopus

  4. Characteristic image on cerebral angiography in ruptured blood blister-like aneurysms

    Kato Naoki, Izumi Takashi, Nishihori Masahiro, Goto Shunsaku, Araki Yoshio, Yokoyama Kinya, Saito Ryuta

    CLINICAL NEUROLOGY AND NEUROSURGERY   Vol. 225   page: 107583   2023.2

     More details

    Language:English   Publisher:Clinical Neurology and Neurosurgery  

    Objective: To evaluate the static and dynamic features of blood blister-like aneurysms (BBAs) using cerebral angiography to identify characteristic features to improve the diagnosis of these uncommon aneurysms. Methods: Digital subtraction angiography (DSA) images were compared between patients with BBAs (n = 12, group A) and patients with unruptured paraclinoid aneurysms ≤ 5 mm in size treated by endovascular procedures (n = 12, group B). DSA images were assessed for irregularities in the diameter of the parent artery and delayed inflow and outflow of contrast medium in the aneurysm. Enlargement of the aneurysm and morphological changes from the first assessment were also evaluated in patients with BBAs. Results: Compared to the group B, group A had a higher proportion of irregular vessel diameter (p = 0.013) and the delayed contrast medium outflow (p = 0.014). As well, stagnation of contrast medium along the aneurysm wall was a characteristic finding of BBAs, even for small aneurysms. Conclusion: Irregular morphological features of the parent artery and delayed contrast medium outflow as characteristic findings of ruptured BBAs may improve the diagnosis of these uncommon aneurysms, which remains challenging in practice.

    DOI: 10.1016/j.clineuro.2022.107583

    Web of Science

    Scopus

    PubMed

  5. The usefulness of three-dimensional fusion imaging of spinal arteriovenous malformation by a workstation connected to angiography systems

    Nagashima Yoshitaka, Izumi Takashi, Nishimura Yusuke, Nishihori Masahiro, Oyama Takahiro, Matsuo Mamoru, Ito Hiroshi, Nishii Tomoya, Saito Ryuta

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 85 ( 1 ) page: 127 - 133   2023.2

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    Digital subtraction angiography (DSA) is the most useful technique for diagnosing spinal arteriovenous malformations (AVM). In recent years, with the improvement of imaging capabilities, the usefulness of three-dimensional (3D) imaging by fusing various modalities has been recognized. The use of 3D fusion imaging with a workstation connected to an angiography system has been reported in many cases of intracranial disease, but less frequently for spinal AVM. In this article, we describe two illustrative cases of spinal AVM in which 3D fusion imaging was useful for treatment. Although 3D fusion images using the system have the disadvantage that only a maximum of two images can be fused, it provides spinal surgeons with useful information for preoperative evaluation in a small amount of time.

    DOI: 10.18999/nagjms.85.1.127

    Web of Science

    Scopus

    PubMed

  6. Differences in gaze behaviors between trainees and experts during endovascular therapy for cerebral aneurysms: a preliminary study using a cerebral aneurysm model

    Otsuka Takafumi, Izumi Takashi, Yamamoto Masaya, Seshita Yusuke, Kohama Takeshi, Nishihori Masahiro, Tsukada Tetsuya, Saito Ryuta

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 85 ( 1 ) page: 50 - 58   2023.2

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    In the neuroendovascular field, the training of operators has become an important issue. Recently, eye-tracking technology has been introduced into various fields of medical education. This study aimed to apply eye-tracking technology to the training of neuroendovascular therapy. Six neurosurgeons, including three neuroendovascular specialists and three trainees, at our institution and related facilities participated in the study. Eye movement was recorded by the eye-tracking device during the microcatheter navigation and coil placement into the silastic aneurysm model under biplane X-ray fluoroscopy. Eye-tracking analysis during neuroendovascular therapy was feasible in all six subjects. In microcatheter navigation, specialists tended to more frequently switch their attention between frontal and lateral images than trainees. In coil embolization, the overall gaze frequency tended to increase, and the average fixation duration tended to decrease as the number of experienced cases increased. Inexperienced operators tend to fix their gaze when they are operators than when they are assistants. More experienced operators tended to look at the microcatheter longer in the coil insertion task. The eye-tracking analysis may be useful for operator training in neuroendovascular therapy. Experts may have moved their eyes more frequently than trainees to gaze at the right place. In the future, it will be necessary to collect gaze data for more operators in various tasks.

    DOI: 10.18999/nagjms.85.1.50

    Web of Science

    Scopus

    PubMed

  7. Four-dimensional digital subtraction angiography for the vascular anatomical diagnosis of dural arteriovenous malformation: Comparison with the conventional method

    Ishikawa Kojiro, Nishihori Masahiro, Izumi Takashi, Oshima Ryosuke, Uemura Takeshi, Kanamori Fumiaki, Uda Kenji, Yokoyama Kinya, Araki Yoshio, Saito Ryuta

    INTERVENTIONAL NEURORADIOLOGY     page: 15910199221145526   2022.12

     More details

    Language:English   Publisher:Interventional Neuroradiology  

    Background: Two-dimensional digital subtraction angiography (2D-DSA) and conventional three-dimensional digital subtraction angiography (3D-DSA) are used for the detailed analysis of dural arteriovenous fistula (DAVF). Recently, four-dimensional digital subtraction angiography (4D-DSA), a novel technology, has been attracting attention. The current study aimed to evaluate the capability of 4D-DSA in assessing anatomical angioarchitecture in DAVF. Methods: In total, 10 consecutive patients with DAVF who underwent 3D-DSA and 4D-DSA at a single institution were included in the analysis. Initially, one-slice multiplanar reconstruction (MPR) images obtained via 4D-DSA and 3D-DSA were compared to investigate the visibility of the feeding artery, fistulous point, and draining vein. Next, 4D-DSA images alone were compared and evaluated with and the MPR images of conventional 3D-DSA in terms of diagnosis of the angioarchitecture. Results: In total, six men and four women (with a mean age of 65.6 ± 10.0 years) were included in the study. The MPR image obtained via 3D-DSA had a significantly better visibility of the feeding artery and fistulous point than that acquired via 4D-DSA (p < 0.05). As for the draining vein, the score was equivalent and not significant. The diagnosis of the vascular architecture of only 4D-DSA images was nearly equivalent to that of MPR images of 3D-DSA. There were no inter-rater differences. Conclusion: The MPR images obtained via 4D-DSA may be slightly inferior to those acquired via 3D-DSA in identifying fine angioarchitecture in DAVF. However, they were comparable in terms of diagnostic accuracy.

    DOI: 10.1177/15910199221145526

    Web of Science

    Scopus

    PubMed

  8. Abnormal foreshortening of a Flow Re-Direction Endoluminal Device caused by in-stent thrombosis immediately after deployment br

    Otsuka Takafumi, Izumi Takashi, Nishihori Masahiro, Tsukada Tetsuya, Goto Shunsaku, Ikezawa Mizuka, Kato Naoki, Nakano Mizuki, Uda Kenji, Yokoyama Kinya, Araki Yoshio, Saito Ryuta

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 84 ( 4 ) page: 884 - 889   2022.11

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    Thromboembolic complications are a concern in the treatment of cerebral aneurysms using a flow diverter. In this study, we report a case of abnormal foreshortening of a Flow Re-Direction Endoluminal Device (FRED) caused by in-stent thrombosis immediately after its deployment. A 72-year-old woman had a large cavernous carotid aneurysm, which caused ptosis and diplopia. FRED deployment was planned, and dual antiplatelet therapy was initiated 2 weeks before the procedure. Under systemic heparinization, FRED was deployed with local compaction over the aneurysm orifice. Cone-beam computed tomography subsequently revealed slightly poor wall apposition at the proximal side. While the balloon catheter was prepared for angioplasty, the stent became abnormally foreshortened, the proximal side slipped into the aneurysm, and the internal carotid artery became occluded. FRED was removed using a snare wire, and recanalization was obtained. The lumen of the removed FRED was filled with thrombus. The antiplatelet therapy was changed to triple regimen, and a Pipeline Flex embolization device was placed 1 month later. At that time, no thromboembolic complications were noted. It was considered that thrombotic occlusion was followed by foreshortening of FRED on the distal side because of antegrade blood flow. Multiple factors, such as increased mesh density by locally compacted stent deployment, slightly poor wall apposition, clopidogrel resistance, and the dual-layer structure of FRED, may have been involved in thrombus formation.

    DOI: 10.18999/nagjms.84.4.884

    Web of Science

    Scopus

    PubMed

  9. Efficacy of comparing coil behavior and distribution using the silicone aneurysm model: difference of coil distribution in the early filling stage

    Goto Shunsaku, Izumi Takashi, Nishihori Masahiro, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Saito Ryuta

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 84 ( 4 ) page: 762 - 771   2022.11

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    This study sought to establish an experimental aneurysm model of visualizing coil insertion using radiolucent nylon coils. Moreover, this study aimed to clarify the characteristics and differences of each coil and use them clinically as indices of coil selection. The coil insertion test was performed on the 10 mm spherical silicone aneurysm model filled to a nylon coil volume embolization ratio of 11.8%. Five types of coil were randomly tested six times, and the distribution of the coils was analyzed by fluoroscopy imaging. Indices of “Area (mm2),” “Feret’s diameter (mm),” and “Circularity” were calculated from the fluoroscopic images. Among the indices, only “Area” showed a significant difference between coils (p = 0.002). On multivariate analysis, “Area” of the ED Infini was larger than those of Target XL soft and Galaxy G3 (p = 0.018 and 0.026, respectively). Furthermore, the area of the 360 soft was larger than that of G3 (p = 0.049). Analysis of the correlation between these values and the coil configuration showed that “Area” was negatively correlated with the stock-wire diameter (r = −0.50; p = 0.004) and primary coil configuration (r = −0.65; p < 0.001). When inserting the coils in the early stage, although the difference between each coil is relatively difficult to obtain, knowledge on the proper use of the coils with differences in characteristics can help in selecting the coil most appropriate for the conditions.

    DOI: 10.18999/nagjms.84.4.762

    Web of Science

    Scopus

    PubMed

  10. The usefulness and safety of dexmedetomidine for postoperative sedation in pediatric patients with moyamoya disease. International journal

    Fumiaki Kanamori, Yoshio Araki, Kinya Yokoyama, Kenji Uda, Michihiro Kurimoto, Yoshiki Shiba, Takashi Mamiya, Kai Takayanagi, Kazuki Ishii, Masahiro Nishihori, Takashi Izumi, Sho Okamoto, Ryuta Saito

    Journal of neurosurgery. Pediatrics   Vol. 30 ( 3 ) page: 301 - 307   2022.9

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    OBJECTIVE: After revascularization surgery in pediatric patients with moyamoya disease (MMD), resting and avoiding crying is important. However, this inaction is often difficult because of pain or anxiety. Dexmedetomidine (DEX), which has sedative and analgesic properties, may be useful in reducing those uncomfortable conditions; however, its common side effects include bradycardia and hypotension, which have a risk of decreasing the cerebral blood flow. The aim of this study was to investigate the efficacy and safety of using DEX for pediatric patients with MMD in the acute period after revascularization surgery. METHODS: This retrospective study included pediatric patients with MMD who underwent revascularization surgery. Based on whether DEX was used for light sedation during postoperative days (PODs) 0-1 after extubation, the patients were divided into DEX or control groups. For neurological outcomes, the incidence of symptomatic cerebral infarction and transient neurological events (TNEs) during PODs 0-1 and the entire hospitalization were investigated. In addition, the Richmond Agitation-Sedation Scale (RASS) was used to assess the effect of DEX, and bradycardia and hypotension were evaluated as side effects. RESULTS: A total of 84 surgical procedures were included in this study (27 in the DEX group and 57 in the control group). During PODs 0-1, symptomatic infarction was not observed in either group. The incidence of TNEs was almost the same in both groups: 2 (7.4%) of the 27 procedures in the DEX group and 4 (7.0%) of the 57 procedures in the control group (p > 0.99). Moreover, the incidences of symptomatic infarction and TNEs during the entire hospitalization did not differ significantly (symptomatic infarction, p > 0.99; TNEs, p = 0.20). Regarding the DEX effect, the median RASS scores during PODs 0-1 were -1.0 (drowsy) in the DEX group and +1.0 (restless) in the control group, showing a significant difference (p < 0.01). Regarding side effects, bradycardia was observed only in 3 (11.1%) of the 27 procedures in the DEX group (p = 0.03), and hypotension was not observed in any of the cases. CONCLUSIONS: In pediatric patients with MMD who are extubated after revascularization surgery, DEX produced appropriate light sedation and analgesia. The risk for symptomatic infarction is almost the same in cases in which DEX is used and those in which it is not; however, neurosurgeons should be cautious of bradycardia and TNEs as potential side effects.

    DOI: 10.3171/2022.6.PEDS2241

    Web of Science

    Scopus

    PubMed

  11. Medical Management of a Mural Thrombus Inducing Repeated Ischemic Strokes in a Patient with Congenital Afibrinogenemia. International journal

    Masahiro Nishihori, Yoshio Araki, Nobuaki Suzuki, Shogo Tamura, Mayo Hattori, Takashi Izumi, Shunsaku Goto, Kinya Yokoyama, Kenji Uda, Tadashi Matsushita, Ryuta Saito

    Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association   Vol. 31 ( 7 ) page: 106526 - 106526   2022.7

     More details

    Language:English  

    OBJECTIVES: Congenital afibrinogenemia is an autosomal recessive inherited disorder that can cause thrombotic as well as hemorrhagic events. We describe a case of repeated mild ischemic strokes due to a mural thrombus in the carotid artery and our medical treatment. CASE DESCRIPTION: A 49-year-old woman with congenital afibrinogenemia developed two minor ischemic strokes in two months. Clinical images revealed scattered fresh infarcts in the right middle cerebral artery region and mild cervical carotid artery stenosis. The risk for surgical treatment was considered to be extraordinarily high. The patient was treated with 100 mg/day of aspirin and 3 g fibrinogen infusion every two weeks. After the one-year course of medication, the mural thrombus gradually decreased, and there were no bleeding or ischemic stroke events. CONCLUSION: This case report highlights the successful treatment of an ischemic stroke in a patient with a congenital afibrinogenemia with an antiplatelet agent and fibrinogen replacement. There are no guidelines for managing ischemic stroke in patients with congenital afibrinogenemia, and further studies are needed.

    DOI: 10.1016/j.jstrokecerebrovasdis.2022.106526

    Web of Science

    Scopus

    PubMed

  12. Changes in cerebral blood flow in the postoperative chronic phase after combined cerebral revascularization for moyamoya disease with ischaemic onset. International journal

    Yoshio Araki, Takashi Mamiya, Naotoshi Fujita, Kenji Uda, Kinya Yokoyama, Fumiaki Kanamori, Kai Takayanagi, Kazuki Ishii, Masahiro Nishihori, Kazuhito Takeuch, Kuniaki Tanahashi, Yuichi Nagata, Yusuke Nishimura, Takafumi Tanei, Masaki Sumitomo, Sho Okamoto, Takashi Izumi, Katsuhiko Kato, Ryuta Saito

    Neurosurgical review   Vol. 45 ( 3 ) page: 2471 - 2480   2022.6

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    The purpose of this study was to examine the effects of combined revascularization for ischaemic-onset moyamoya disease (MMD) on cerebral haemodynamics by comparing cerebral blood flow (CBF) during the postoperative chronic phase with preoperative CBF. A retrospective cohort of 24 MMD patients (representing 31 surgeries) who received single photon emission computed tomography (SPECT) before and more than 6 months after surgery was investigated. The CBF value of each vascular territory was extracted from SPECT data, and the value relative to the ipsilateral cerebellar value (relative CBF, or RCBF) was calculated. The correlation between the revascularization effect and the proportional change in RCBF before and after surgery (calculated as post-RCBF/pre-RCBF ("post/pre-RCBF")) was analysed. Furthermore, the relationships between changes in neurological symptoms and post/pre-RCBF were investigated. Preoperative and postoperative mean RCBF values were 0.92 ± 0.15 and 0.96 ± 0.13 (p = 0.619) in the anterior cerebral artery territory, 0.99 ± 0.17 and 1.01 ± 0.17 (p = 0.598) in the middle cerebral artery territory and 1.15 ± 0.22 and 1.14 ± 0.19 (p = 0.062) in the posterior cerebral artery territory, respectively. No significant correlation was found between the revascularization score and post/pre-RCBF. The revascularization score and post/pre-RCBF were not significant predictors of worsening neurological symptoms postoperatively. No significant change in RCBF was observed in any vascular territory in the chronic phase after revascularization. Combined revascularization may assist in the redirection of blood flow from the internal to the external carotid system and contribute to CBF maintenance.

    DOI: 10.1007/s10143-022-01774-8

    Web of Science

    Scopus

    PubMed

  13. Evaluation of the differences in pressure applied to the vessel wall by different types of balloon remodeling microcatheters in an experimental model

    Ikezawa Mizuka, Izumi Takashi, Nishihori Masahiro, Tsukada Tetsuya, Tamari Yosuke, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Goto Shunsaku, Kropp Asuka E., Otsuka Takafumi, Kato Naoki, Nakano Mizuki, Saito Ryuta

    INTERVENTIONAL NEURORADIOLOGY   Vol. 28 ( 3 ) page: 323 - 331   2022.6

     More details

    Language:Japanese   Publisher:Interventional Neuroradiology  

    Background: We examined compliance differences among balloon remodeling microcatheters, which have not been established previously. Methods: Straight and 120° angulated vascular models were created in a 3 mm diameter tube with 3 mm hole (vascular model A), a tube with a 4 mm hole (vascular model B), and a 4 mm diameter tube (vascular model C). We compared the pressure exerted when each balloon was herniated 1 or 2 mm between three compliant balloons (SHOURYU SR, TransForm C, and Scepter C) and four super-compliant balloons (HyperForm, SHOURYU HR, TransForm SC, and Scepter XC). Results: In vascular model A, there was a significant difference in the pressure exerted by compliant balloons and super-compliant balloons in both the straight and angulated models. In the straight model (1 and 2 mm), the lowest pressure was exerted by HyperForm (super-compliant balloons group) and SHOURYU SR (compliant balloons group). The lowest pressure was exerted in the angulated model by HyperForm (super-compliant balloons group) and Scepter C (compliant balloons group). The Scepter balloon exerted higher pressure in the straight model than other balloon remodeling microcatheters but less in the angulated model. In vascular model B, the pressure decreased in all balloons compared with model A. In vascular model C, the pressure increased in all balloons compared with model A. Conclusions: Pressure differed across balloon remodeling microcatheters. In addition, vessel shape and diameter, and hole size, affected the results. Our findings can help select balloon remodeling microcatheters.

    DOI: 10.1177/15910199211031765

    Web of Science

    Scopus

    PubMed

  14. Blood flow stagnation after treatment of a giant internal carotid artery aneurysm: a computed fluid dynamics analysis. Reviewed International journal

    Shinsuke Muraoka, Reiya Takagi, Yoshio Araki, Kenji Uda, Masaki Sumitomo, Sho Okamoto, Masahiro Nishihori, Takashi Izumi, Masanori Nakamura, Ryuta Saito

    Scientific reports   Vol. 12 ( 1 ) page: 7283 - 7283   2022.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Balloon test occlusion (BTO) is an angiographic test to evaluate ischemic tolerance after permanent occlusion of an internal carotid artery (ICA). BTO can simulate ischemia caused by parent artery occlusion and can be used to select a suitable bypass surgery using specific criteria. On the other hand, a postoperative thrombus can form despite proper case selection, optimal radiological evaluation, and an appropriate surgical strategy. Postoperative ischemic complications related to perforating branches are clinically significant. This simulation study aimed to analyze postoperative flow characteristics and elucidate the cause of ischemic complications related to the perforating branch using computational fluid dynamics (CFD). An unexpected postoperative thrombus formation related to the perforating branch occurred after treating a giant aneurysm in the cavernous portion of the ICA in a patient. Three-dimensional digital subtraction angiography was used to acquire flow data and set up the CFD simulation. The flow simulations were performed at various bypass flow rates. The CFD analysis indicated flow stagnation in the ICA only when surgical treatment using a low-flow bypass graft was performed. Thrombus formation may lead to ischemic complications related to the perforating branch, such as the anterior choroidal artery. BTO did not reflect the influence of bypass blood flow. Therefore, recognizing that blood flow stagnation may occur and comprehensively deciding on the surgical strategy by CFD analysis can be helpful to prevent ischemic complications in patients with giant aneurysms.

    DOI: 10.1038/s41598-022-11321-6

    Web of Science

    Scopus

    PubMed

  15. Advantages of petrosectomy for superficial temporal artery to superior cerebellar artery bypass based on three-dimensional distance measurements using cadaver heads

    Uda Kenji, Tanahashi Kuniaki, Mamiya Takashi, Kanamori Fumiaki, Yokoyama Kinya, Nishihori Masahiro, Izumi Takashi, Araki Yoshio, Saito Ryuta

    NEUROSURGICAL REVIEW   Vol. 45 ( 2 ) page: 1617 - 1624   2022.4

     More details

    Language:English   Publisher:Neurosurgical Review  

    Superficial temporal artery (STA) to superior cerebellar artery (SCA) bypass is usually performed via the subtemporal approach (StA), anterior transpetrosal approach (ApA), or combined petrosal approach (CpA), but no study has yet reported a quantitative comparison of the operative field size provided by each approach, and the optimal approach is unclear. The objective of this study is to establish evidence for selecting the approach by using cadaver heads to measure the three-dimensional distances that represent the operative field size for STA–SCA bypass. Ten sides of 10 cadaver heads were used to perform the four approaches: StA, ApA with and without zygomatic arch osteotomy (ApA-ZO− and ApA-ZO+), and CpA. For each approach, the major-axis length and the minor-axis length at the anastomosis site (La-A and Li-A), the major-axis length and the minor-axis length at the brain surface (La-B and Li-B), the depth from the brain surface to the anastomosis site (Dp), and the operating angles of the major axis and the minor axis (OAa and OAi) were measured. Shallower Dp and wider operating angle were obtained in the order CpA, ApA-ZO+, ApA-ZO−, and StA. In all parameters, ApA-ZO− extended the operative field more than StA. ApA-ZO+ extended La-B and OAa more than ApA-ZO−, whereas it did not contribute to Dp and OAi. CpA significantly decreased Dp, and widened OAa and OAi more than ApA-ZO+. ApA and CpA greatly expanded the operative field compared with StA. These results provide criteria for selecting the optimal approach for STA-SCA bypass in light of an individual surgeon’s anastomosis skill level.

    DOI: 10.1007/s10143-021-01686-z

    Web of Science

    Scopus

    PubMed

  16. Risk Factors for Cerebral Infarction Early After Revascularization in Children Younger than 5 Years with Moyamoya Disease. International journal

    Yoshio Araki, Kenji Uda, Kinya Yokoyama, Fumiaki Kanamori, Michihiro Kurimoto, Yoshiki Shiba, Takashi Mamiya, Masahiro Nishihori, Kazuhito Takeuchi, Kuniaki Tanahashi, Yuichi Nagata, Yusuke Nishimura, Sho Okamoto, Masaki Sumitomo, Takashi Izumi, Ryuta Saito

    World neurosurgery   Vol. 160   page: E220 - E226   2022.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    OBJECTIVE: Cerebral revascularization is necessary for pediatric patients younger than 5 years with moyamoya disease (MMD). However, they have a high risk of developing cerebral infarction early after surgery. This study aimed to analyze the risk factors for developing cerebral infarction among these patients. METHODS: The charts of 21 consecutive patients with MMD (39 surgeries) younger than 5 years who had undergone revascularization at our hospital were retrospectively analyzed. Because cerebral infarction occurring within 1 month after surgery was the primary end point, other clinical information was evaluated, including each surgical procedure. Multivariate analysis of the risk factors for postoperative cerebral infarction was performed. RESULTS: Cerebral infarction occurred after 7 of 39 surgeries (17.9%). Of the 39 surgeries, 23 (59%) included direct and indirect combined revascularization. The incidence of cerebral infarction did not differ significantly between the combined (21.7%) and indirect (12.5%) groups (P = 0.46). Logistic regression showed no association between the revascularization procedure and the occurrence of cerebral infarction after surgery (P = 0.3). However, younger age at surgery was correlated with a higher risk of developing cerebral infarction in the early postoperative period (P = 0.05). CONCLUSIONS: No differences were found in the risk of developing cerebral infarction early after surgery as a result of surgical procedures. However, younger patients had higher postoperative risk. Further multicenter research should examine this issue for young pediatric patients with moyamoya at high risk of developing cerebral infarction.

    DOI: 10.1016/j.wneu.2021.12.115

    Web of Science

    Scopus

    PubMed

  17. Challenging direct bypass surgery for very young children with moyamoya disease: technical notes. International journal

    Yoshio Araki, Kenji Uda, Kinya Yokoyama, Fumiaki Kanamori, Michihiro Kurimoto, Yoshiki Shiba, Takashi Mamiya, Masahiro Nishihori, Kazuhito Takeuchi, Kuniaki Tanahashi, Yuichi Nagata, Yusuke Nishimura, Sho Okamoto, Masaki Sumitomo, Takashi Izumi, Ryuta Saito

    Neurosurgical review   Vol. 45 ( 2 ) page: 1799 - 1807   2022.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Cerebral revascularization for moyamoya disease (MMD) is an effective treatment for improving cerebral ischaemia and preventing rebleeding. Although direct bypass surgery is commonly performed on older children and adults, it is challenging in very young children due to the high difficulty level of the procedure. The subjects were MMD patients under 3 years of age on whom surgery was performed by a single surgeon (Y.A.). Preoperative clinical findings, information related to direct bypass surgery, bypass patency, and the incidence of postoperative stroke were investigated. Combined revascularization, including direct bypass surgery, was performed on 3 MMD patients (3 sides) under 3 years of age. The average diameter of the grafts used in direct bypass was 0.8 mm. The average recipient diameter was 0.8 ± 0.17 (range 0.6-1) mm. In all cases, the anastomotic procedure was completed using 11-0 monofilament nylon thread, and patency was confirmed. Direct bypass for MMD patients under 3 years old is technically challenging. However, despite the anatomical differences between very young children and elderly individuals, direct bypass surgery could certainly be completed. In addition, a rapid recovery from cerebral blood flow insufficiency could yield a promising neurological outcome.

    DOI: 10.1007/s10143-021-01685-0

    Web of Science

    Scopus

    PubMed

  18. Spatially separate cerebral infarction in the posterior cerebral artery territory after combined revascularization of the middle cerebral artery territory in an adult patient with moyamoya disease and fetal-type posterior communicating artery: illustrative case. International journal

    Yoshio Araki, Kinya Yokoyama, Kenji Uda, Fumiaki Kanamori, Takashi Mamiya, Kai Takayanagi, Kazuki Ishii, Masahiro Nishihori, Kazuhito Takeuchi, Kuniaki Tanahashi, Yuichi Nagata, Takafumi Tanei, Yusuke Nishimura, Takashi Izumi, Ryuta Saito

    Journal of neurosurgery. Case lessons   Vol. 3 ( 12 )   2022.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: Remote cerebral infarction after combined revascularization of the middle cerebral artery (MCA) territory is rare in patients with moyamoya disease (MMD) with a fetal-type posterior communicating artery (PCoA). OBSERVATIONS: A 57-year-old woman developed numbness in her right upper limb and transient motor weakness and was diagnosed with MMD. She also had a headache attack and a scintillating scotoma in the right visual field. Preoperative magnetic resonance angiography (MRA) showed stenosis of the left posterior cerebral artery (PCA). Combined revascularization was performed for the left MCA territory. No new neurological deficits were observed for 2 days after the operation, but right hemianopia, alexia, and agraphia appeared on postoperative day (POD) 4. Magnetic resonance imaging showed a new left occipitoparietal lobe infarction, and MRA showed occlusion of the distal left PCA. After that point, the alexia and agraphia gradually improved, but right hemianopia remained at the time of discharge on POD 18. LESSONS: Cerebral ischemia in the PCA territory may occur after combined revascularization of the MCA territory in patients with fetal-type PCoA. For these cases, a double-barrel bypass or indirect revascularization to induce a slow conversion could be considered on its own as a treatment option.

    DOI: 10.3171/CASE21704

    PubMed

  19. Comparison of hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment for internal carotid artery aneurysm

    Tsukada Tetsuya, Izumi Takashi, Isoda Haruo, Nishihori Masahiro, Kropp A. Elisabeth, Mizuno Takashi, Wakabayashi Toshihiko

    JOURNAL OF NEUROSURGERY   Vol. 136 ( 3 ) page: 619 - 626   2022.3

     More details

    Language:English   Publisher:Journal of Neurosurgery  

    OBJECTIVE De novo aneurysms generally develop in healthy vessels after parent artery occlusion for large internal carotid artery (ICA) aneurysm, possibly owing to increased hemodynamic stress in the remaining vessels. In recent years, there has been a shift toward flow diverter stent treatment. However, there is a lack of direct evidence and data that prove this change in hemodynamic stress in healthy vessels after parent artery occlusion and flow diverter stent treatment. The authors compared hemodynamic stress in healthy-side vessels before and after parent artery occlusion and flow diverter treatments. METHODS The authors included patients who underwent 3D cine phase-contrast MRI before and after large ICA aneurysm treatment. Spatially and temporally averaged volume flow rates and spatially averaged systolic wall shear stress (WSS) in healthy-side ICA distal to the posterior communicating artery (C1 segment according to Fisher's classification) were measured before and after parent artery occlusion and flow diverter treatments. RESULTS Seventeen patients were included (5 patients in the parent artery occlusion group and 12 in the flow diverter group). At 1-2 months after treatment, median volume flow rate in healthy-side ICA increased from 5.36 ml/sec to 6.28 ml/sec (total increase 117%, p = 0.04) in the parent artery occlusion group and from 4.65 ml/sec to 4.93 ml/sec (total increase 106%, p = 0.02) in the flow diverter group. In the parent artery occlusion group, median WSS in the C1 segment of the healthy-side ICA increased from 3.91 Pa to 5.61 Pa (total increase 143%, p = 0.08); however, no significant increase was observed in the flow diverter group (4.29 Pa to 4.57 Pa [total increase 107%, p = 0.21]). CONCLUSIONS Postoperatively, volume flow rate and WSS in the C1 segment of the healthy-side ICA significantly increased in the parent artery occlusion group. Therefore, the parent artery occlusion group was more prone to de novo aneurysm than the flow diverter group.

    DOI: 10.3171/2021.2.JNS204185

    Web of Science

    Scopus

    PubMed

  20. Paradoxical symptomatic cerebral blood flow decreases after combined revascularization surgery for patients with pediatric moyamoya disease: illustrative case. International journal

    Yoshio Araki, Kinya Yokoyama, Kenji Uda, Fumiaki Kanamori, Michihiro Kurimoto, Yoshiki Shiba, Takashi Mamiya, Kai Takayanagi, Kazuki Ishii, Masahiro Nishihori, Kazuhito Takeuchi, Kuniaki Tanahashi, Yuichi Nagata, Yusuke Nishimura, Sho Okamoto, Masaki Sumitomo, Takashi Izumi, Ryuta Saito

    Journal of neurosurgery. Case lessons   Vol. 3 ( 3 )   2022.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: Transient neurological deficits (TNDs) develop after cerebral revascularization in patients with moyamoya disease (MMD). The authors report a rare pediatric MMD case with extensive decreased cerebral blood flow (CBF) and prolonged TNDs after combined revascularization. OBSERVATIONS: A 9-year-old boy presented with transient left upper limb weakness, and MMD was diagnosed. A right-sided combined surgery was performed. Two years after the surgery, frequent but transient facial (right-sided) and upper limb weakness appeared. The left internal carotid artery terminal stenosis had progressed. Therefore, a left combined revascularization was performed. The patient's motor aphasia and right upper limb weakness persisted for approximately 10 days after surgery. Magnetic resonance angiography showed that the direct bypass was patent, but extensive decreases in left CBF were observed using single photon emission tomography. With adequate fluid therapy and blood pressure control, the neurological symptoms eventually disappeared, and CBF improved. LESSONS: The environment of cerebral hemodynamics is heterogeneous after cerebral revascularization for MMD, and the exact mechanism of CBF decreases was not identified. TNDs are significantly associated with the onset of stroke during the early postoperative period. Therefore, appropriate treatment is desired after determining complex cerebral hemodynamics using CBF studies.

    DOI: 10.3171/CASE21628

    PubMed

  21. Atypical Incomplete Detachment Following PulseRider Deployment

    Goto Shunsaku, Izumi Takashi, Nishihori Masahiro, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Saito Ryuta

    Journal of Neuroendovascular Therapy   Vol. 16 ( 8 ) page: 409 - 412   2022

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective</b>: Owing to the limited time since the introduction of the PulseRider (PR), inconsequential or rare complications that clinicians should be aware of remain unreported yet. Here, we report a rare complication of incomplete detachment.</p><p><b>Case Presentation</b>: A 50-year-old male underwent PR-assisted coil embolization for a basilar tip aneurysm. Coiling was completed, and the detachment procedure was performed using a detachment machine; the success signal was observed. The delivery microcatheter was subsequently advanced back up to the proximal markers, and no reapproximation of the proximal markers, which indicates successful detachment, was observed. However, only one of the proximal markers returned to the microcatheter, and incomplete detachment of only one leg was detected. Ultimately, electrical detachment was not possible, and physical separation by tension was achieved.</p><p><b>Conclusion</b>: Our case report presents a rare case of a detachment problem in the PR. The PR could not be detached, although the signal revealed successful detachment. Therefore, careful withdrawal of the delivery wire by checking not only the proximal markers but also the behavior of the entire PR and coil complex is important.</p>

    DOI: 10.5797/jnet.cr.2021-0095

    CiNii Research

  22. The preoperative focal cerebral blood flow status may be associated with slow flow in the bypass graft after combined surgery for moyamoya disease. International journal

    Yoshio Araki, Kinya Yokoyama, Kenji Uda, Fumiaki Kanamori, Takashi Mamiya, Kai Takayanagi, Kazuki Ishii, Kazunori Shintai, Masahiro Nishihori, Tetsuya Tsukada, Kazuhito Takeuchi, Kuniaki Tanahashi, Yuichi Nagata, Yusuke Nishimura, Takafumi Tanei, Yoshitaka Nagashima, Shinsuke Muraoka, Takashi Izumi, Yukio Seki, Ryuta Saito

    Surgical neurology international   Vol. 13   page: 511 - 511   2022

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: The aim of this study was to investigate the association between early postoperative slow flow in bypass grafts and preoperative focal cerebral blood flow (CBF) in patients who underwent combined surgery for moyamoya disease (MMD). METHODS: The subjects were 18 patients (22 surgeries) who underwent single photon emission computed tomography (SPECT) before surgery. The CBF value of the middle cerebral artery territory was extracted from the SPECT data, and the value relative to the ipsilateral cerebellar CBF (relative CBF, or RCBF) was calculated. The association between RCBF and early postoperative slow flow in the bypass graft was investigated. In addition, the correlation between the revascularization effect and preoperative RCBF was analyzed. RESULTS: In four of 22 surgeries (18.2%), slow flow in the bypass graft was identified in the early postoperative period. Preoperative RCBF in the slow flow and patent groups was 0.86 ± 0.15 and 0.87 ± 0.15, respectively, with no significant difference (P = 0.72). The signal intensity of four slow-flowed bypasses was improved in all cases on magnetic resonance angiography images captured during the chronic phase (mean of 3.3 months postoperatively). The revascularization scores were 2 ± 0.82 and 2.1 ± 0.68 in the slow flow and patent groups, respectively, and did not differ significantly (P = 0.78). A significant correlation was not observed between preoperative RCBF and the revascularization effect. CONCLUSION: No significant association was observed between preoperative RCBF and early postoperative slow flow in bypass grafts in patients with MMD undergoing combined surgery. Given the high rate of improved depiction of slow-flowed bypass in the chronic postoperative phase, the conceptual significance of an opportune surgical intervention is to maintain CBF by supporting the patient's own intracranial-extracranial conversion function.

    DOI: 10.25259/SNI_772_2022

    Scopus

    PubMed

  23. Contrast-Enhanced Magnetic Resonance Imaging Suggested a Possibility of Transvenous Embolization in the Superior Petrosal Sinus Dural Arteriovenous Fistula: A Case Report

    Nishihori Masahiro, Izumi Takashi, Tsukada Tetsuya, Kato Yutaka, Uda Kenji, Yokoyama Kinya, Araki Yoshio, Saito Ryuta

    Journal of Neuroendovascular Therapy   Vol. 16 ( 3 ) page: 163 - 169   2022

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective</b>: Superior petrosal sinus dural arteriovenous fistula (SPS-DAVF) is a rare subtype of intracranial DAVF that sometimes leads to hemorrhagic symptoms following deep venous drainage. Here we report the case of SPS-DAVF with retrograde venous reflux to the cerebellar vein. Preoperative contrast-enhanced MRI was a decisive factor in a safe and effective treatment.</p><p><b>Case Presentation</b>: A 37-year-old woman was referred to our hospital with abnormal MRI findings, which was performed when she had a mild headache during her check-up. DSA revealed left-sided SPS-DAVF, which was diagnosed as Cognard type IIb. Both CTA and DSA could not detect the whole SPS but only the shunt pouch. Using contrast-enhanced MRI, we were able to visualize the presence of the SPS and its continuity within the shunt pouch. 3D-T1 turbo spin echo (SPACE) showed a low-intensity area in the SPS, which was not seen in the 3D-T1 fast field echo (FFE). During the procedure, there was a point where it was difficult to advance the microcatheter, which coincided with the low-intensity area. We achieved effective transvenous embolization from the occluded venous access by devising a surgical technique.</p><p><b>Conclusion</b>: In addition to the contrast-enhanced 3D-T1 FFE, 3D-T1 SPACE might provide beneficial information for endovascular therapy in the evaluation of venous sinuses, which could not be detected by standard examinations.</p>

    DOI: 10.5797/jnet.cr.2021-0029

    CiNii Research

  24. Postoperative stroke and neurological outcomes in the early phase after revascularization surgeries for moyamoya disease: an age-stratified comparative analysis. International journal

    Yoshio Araki, Kinya Yokoyama, Kenji Uda, Fumiaki Kanamori, Michihiro Kurimoto, Yoshiki Shiba, Takashi Mamiya, Masahiro Nishihori, Takashi Izumi, Masaki Sumitomo, Sho Okamoto, Kota Matsui, Ryo Emoto, Toshihiko Wakabayashi, Shigeyuki Matsui, Atsushi Natsume

    Neurosurgical review   Vol. 44 ( 5 ) page: 2785 - 2795   2021.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Stroke and neurological outcomes in the early phase following revascularization for moyamoya disease (MMD) may depend on the patient's age. In this study, an age-stratified comparative analysis was performed to clarify this issue. We reviewed 105 MMD patients who underwent 179 revascularization surgeries. The demographic characteristics were collected in four age groups (≤ 5 and 6-17 years for pediatric patients and 18-49 and ≥ 50 years for adults). Additionally, we assessed the incidence of subsequent stroke and deterioration of modified Rankin Scale (mRS) score. Then, we evaluated predictors of postoperative stroke and mRS deterioration using logistic regression. The mean patient age was 26.2 ± 18.5 years. No significant difference in the incidence of postoperative stroke was observed between age groups; however, the incidence tended to be increased among patients aged ≤ 5 years (17.9%) and patients aged ≥ 50 years (16.7%). Deterioration of mRS scores was significantly associated with ages ≤ 5 years (17.9%) and ≥ 50 years (11.1%). Logistic regression showed that posterior cerebral artery involvement (odds ratio [OR], 4.6) and postoperative transient neurological events (TNEs) (OR, 5.93) were risk factors for postoperative stroke. Age ≤ 5 years (OR, 9.73), postoperative TNEs (OR, 7.38), and postoperative stroke (OR, 49) were identified as predictors of unfavorable neurological outcomes. The novel feature of this comparative analysis by age group is that membership in the early-childhood MMD patient group (under 5 years old) was an independent risk factor for unfavorable short-term neurological outcomes and was mainly associated with the incidence of postoperative severe cerebral infarction.

    DOI: 10.1007/s10143-020-01459-0

    Web of Science

    Scopus

    PubMed

  25. Triggering of Carotid Sinus Reflex during Deployment of the Flow-diverter Device

    GOTO Shunsaku, IZUMI Takashi, NISHIHORI Masahiro, TSUKADA Tetsuya, ARAKI Yoshio, UDA Kenji, YOKOYAMA Kinya, SAITO Ryuta

    Neurologia medico-chirurgica   Vol. 61 ( 10 ) page: 583 - 590   2021.10

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>The carotid sinus reflex (CSR) is a rare complication of the Pipeline Embolization Device (PED) deployment. No study has assessed the potential risk factors in a case series. The purpose of this study was to examine CSR triggering during PED deployment. Thirty-seven consecutive patients who underwent PED deployment were included. All procedures were performed under local anesthesia with mild sedation. We retrospectively analyzed patient characteristics, PED deployment time, and vital signs during the procedure. The vital signs included the pulse rate (PR) and systolic blood pressure (SBP) obtained at three timepoints (pre-deployment, during deployment, post-deployment). We examined the triggering of the CSR during PED deployment by comparing the vital signs at the three timepoints. Moreover, risk factors for CSR were analyzed with univariate analysis. The patients’ average age was 66.3 years. The average size of the aneurysm was 18.0 mm. Six patients (16.2%) showed a decline in the SBP or PR defined as CSR. One patient had a transient cardiac arrest and two had severe transient bradycardia. Deployment into the ophthalmic segment of the internal carotid artery (C2 segment) aneurysm (p = 0.022), prolonged PED deployment time more than 14.5 minutes (p = 0.005), and an acute angle of the anterior genu less than 51.5 degrees (p = 0.005) were risk factors in triggering CSR. CSR may be triggered during PED deployment under local anesthesia with mild sedation. Deployment to the C2 segment aneurysm, prolonged PED deployment time, and an acute angle of the anterior genu were associated with CSR triggering.</p>

    DOI: 10.2176/nmc.oa.2021-0049

    Web of Science

    Scopus

    PubMed

    CiNii Research

  26. Streak Metal Artifact Reduction Technique in Cone Beam Computed Tomography Images after Endovascular Neurosurgery

    OTSUKA Takafumi, NISHIHORI Masahiro, IZUMI Takashi, UEMURA Takeshi, SAKAI Takashi, NAKANO Mizuki, KATO Naoki, KANAMORI Fumiaki, TSUKADA Tetsuya, UDA Kenji, YOKOYAMA Kinya, ARAKI Yoshio, SAITO Ryuta

    Neurologia medico-chirurgica   Vol. 61 ( 8 ) page: 468 - 474   2021.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:The Japan Neurosurgical Society  

    <p>Cone beam computed tomography (CBCT) images are degraded by artifacts due to endovascular implants. We evaluated the use of streak metal artifact reduction technique (SMART) in non-contrast CBCT images after endovascular neurosurgery obtained from 148 patients (125 with aneurysm and 23 with dural arteriovenous fistula [dAVF]). Three neurosurgeons evaluated the cistern and brain surface visibility in CBCT images with and without SMART correction based on a 4-point scale (1, excellent; 2, good; 3, limited; and 4, insufficient). Significant improvement in visibility was achieved when the median scores improved from 4 or 3 to 2 or 1 or from 2 to 1. Metal artifact reduction in adjacent slices without metal and new artifacts after SMART correction was also examined. A significant improvement was achieved regarding the visibility of the cistern in 90 (60.8%) images and of the brain surface in 108 (73.0%) images. Metal size (cistern: odds ratio [OR], 0.91 per 1 mm increase; 95% confidence interval [CI], 0.83–0.99), irregular metal shape (cistern: OR, 0.18; 95% CI, 0.05–0.60 and brain surface: OR, 0.15; 95% CI, 0.05–0.45), and infratentorial lesions (cistern: OR, 0.37; 95% CI, 0.14–0.96 and brain surface: OR, 0.30; 95% CI, 0.11–0.80) were negatively correlated with improved visibility. Metal artifact reduction in adjacent slices without metal was obtained in 25.6% and 34.8% of images with aneurysm and dAVF, respectively. New artifacts after SMART correction were found in 4.8% and 13.0% of images with aneurysm and dAVF, respectively. SMART is especially effective for supratentorial small aneurysms.</p>

    DOI: 10.2176/nmc.oa.2021-0014

    Web of Science

    Scopus

    PubMed

    CiNii Research

  27. Indocyanine green emission timing of the recipient artery in revascularization surgery for moyamoya disease

    Kanamori Fumiaki, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Mamiya Takashi, Nishihori Masahiro, Izumi Takashi, Okamoto Sho, Natsume Atsushi

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 83 ( 3 ) page: 523 - 534   2021.8

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    In superficial temporal artery to middle cerebral artery anastomosis with indirect revascularization for patients with moyamoya disease, the optimal method for selecting the most appropriate cortical artery for the recipient in anastomosis has not been established. We investigated the relationship between the fluorescence emission timing of the recipient artery in the preanastomosis indocyanine green videoangiography and operative outcomes. This retrospective study included 51 surgical revascularization procedures for 39 moyamoya disease patients. The enrolled surgical procedures were classified into three groups based on the fluorescence emission timing of the recipient artery in preanastomosis indocyanine green videoangiography: the EARLIEST, the INTERMEDIATE, and the LATEST. Clinical characteristics and operative outcomes were also collected. The occurrence of white thrombus at the anastomosis site and symptomatic hyperperfusion showed significant differences between the groups classified by the fluorescence emission timing of the recipient artery in preanastomosis indocyanine green videoangiography (white thrombus, p = 0.001; symptomatic hyperperfusion, p = 0.026). The development of white thrombi was significantly higher in the LATEST group, and all symptomatic hyperperfusion was observed in the EARLIEST group. These results indicated that the LATEST group had a significantly higher risk for developing white thrombus, and the EARLIEST group was prone to occur symptomatic hyperperfusion. Selecting the recipient artery based on evaluating the fluorescence emission timing in preanastomosis indocyanine green videoangiography may be useful in reducing perioperative complications.

    DOI: 10.18999/nagjms.83.3.523

    Web of Science

    Scopus

    PubMed

  28. Evaluation of the Straightening Phenomenon of Various Types of Coils

    ISHIDA Mamoru, IZUMI Takashi, ARAKI Yoshio, NISHIHORI Masahiro, YOKOYAMA Kinya, UDA Kenji, TSUKADA Tetsuya, WAKABAYASHI Toshihiko

    Neurologia medico-chirurgica   Vol. 61 ( 6 ) page: 356 - 360   2021.6

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>The straightening phenomenon is known as a cause of catheter kickback in the late phase of coil embolization. The mechanism is supposed to be the relative shortage of the stretch resistance (SR) line, and it occurs when a coil is folded too small. Among many SR coils available, there should be a coil-specific tendency to cause this phenomenon. Here, we conducted an in-vitro experiment to know which coil is the most resistant to the straightening phenomenon. We developed an experimental model to reproduce the straightening phenomenon. Five different coils (Axium Prime, ED Coil, Hypersoft, SMART Coil, and Target 360 nano) of the same size (3 mm × 6 cm) were investigated for five times each. Resistance to the straightening phenomenon, which is represented by the insertion length at the onset of the phenomenon, was compared among coil types. The straightening phenomenon was successfully observed in all insertions. Insertion lengths were significantly different among coil types (p = 0.013). The insertion length of ED was the longest (mean ± SD, 27.0 ± 8.3 mm), which means the most resistant to the phenomenon. Axium was second (21.6 ± 7.0 mm), followed by Target (15.8 ± 6.9 mm), Hypersoft (13.8 ± 5.8 mm), and SMART (12.4 ± 4.7 mm). Difference between ED and Hypersoft (p = 0.037) and difference between ED and Smart (p = 0.018) were significant. ED coil was the one with the most resistance to the straightening phenomenon. Selecting the optimal coil is the key to avoid the phenomenon.</p>

    DOI: 10.2176/nmc.oa.2020-0348

    Web of Science

    Scopus

    PubMed

    CiNii Research

  29. Effects of aspirin and heparin treatment on perioperative outcomes in patients with Moyamoya disease Reviewed International journal

    Kanamori Fumiaki, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Mamiya Takashi, Nishihori Masahiro, Izumi Takashi, Okamoto Sho, Natsume Atsushi

    ACTA NEUROCHIRURGICA   Vol. 163 ( 5 ) page: 1485 - 1491   2021.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Acta Neurochirurgica  

    Background: When superficial temporal artery-middle cerebral artery bypass is combined with indirect methods (e.g., revascularization surgery) to treat Moyamoya disease (MMD), antiplatelet treatment can impact bypass patency, infarction, or hemorrhage complications. Recently, heparin has been proposed as an anticoagulant treatment against white thrombus at the anastomosis site. The study aims to evaluate the effect of aspirin on the perioperative outcomes and investigate the results of heparin treatment for white thrombus. Methods: This retrospective study included 74 procedures of combined revascularization surgery for MMD patients who either received or did not receive aspirin. Perioperative outcomes were compared between the two groups. In addition, the effects of heparin treatment for white thrombus were evaluated. Results: The rate of white thrombus at the anastomosis site was significantly higher in the non-aspirin medication group (univariate: p = 0.032, multivariate: p = 0.044) and, accordingly, initial bypass patency was lower in the non-aspirin medication group (p = 0.049). Of the 17 patients with white thrombus development, five received heparin injections, and all white thrombi disappeared; however, there was one case of epidural hematoma and another of subdural hematoma. The risk of hemorrhagic complications was significantly higher in the surgical procedures that received heparin injections (p = 0.021). Conclusions: In MMD patients who received combined revascularization surgery, aspirin medication lowered the occurrence of white thrombus. Heparin injections help to treat white thrombus but can enhance the risk of hemorrhagic complications.

    DOI: 10.1007/s00701-020-04668-0

    Web of Science

    Scopus

    PubMed

  30. Ipsilateral late stroke after revascularization surgery for patients with Moyamoya disease

    Araki Yoshio, Yokoyama Kinya, Uda Kenji, Kanamori Fumiaki, Mamiya Takashi, Nishihori Masahiro, Sumitomo Masaki, Okamoto Sho, Izumi Takashi

    ACTA NEUROCHIRURGICA   Vol. 163 ( 5 ) page: 1493 - 1502   2021.5

     More details

    Language:English   Publisher:Acta Neurochirurgica  

    Background: Ipsilateral late stroke events occurring after cerebral revascularization for Moyamoya disease (MMD) and their risk factors have not been fully investigated. Methods: We retrospectively analyzed 123 patients with MMD who underwent 212 revascularizations. We investigated preoperative demographic data, surgical procedures, and ipsilateral stroke events occurring more than 1 month after surgery. The effect of revascularization and the residual Moyamoya vessel (MMV) score were examined using magnetic resonance angiography (MRA). Then, predictive factors for postoperative late stroke occurrence were evaluated by logistic regression. Results: The mean age was 26 ± 18.4 years (range 1 to 66 years). Ipsilateral late stroke events were present in 11 of 123 (9%) patients. Stroke occurred in 11 out of 212 surgeries (5.2%) on a hemispheric basis. During the 1300.1 hemisphere-years of follow-up more than 1 month after surgery, the annual stroke rate was 0.84%. The postoperative MRA time-of-flight image showed a mean revascularization score of 1.82 ± 0.6 and a mean residual MMV score of 1.91 ± 0.83. Postoperative strokes occurring within 1 month after cerebral revascularization (36.4%, p = 0.0026) and lower revascularization scores (1.82 ± 0.6 vs 2.51 ± 0.59, p = 0.0006) were significant factors related to the presence of ipsilateral late stroke. Logistic regression showed that stroke events within 1 month after revascularization (odds ratio [OR], 9.79; 95% confidence interval [CI], 0.02–0.57; p = 0.0103), low revascularization score (OR, 0.15; 95% CI, 0.001–0.37; p = 0.0069), and high residual MMV score (OR, 16.2; 95% CI, 1.88–187.4; p = 0.0107) were risk factors for ipsilateral stroke more than 1 month after revascularization. Conclusions: MMD patients who have a stroke within 1 month after cerebral revascularization are at high risk for late strokes. Less effective revascularization or remarkable residual MMV are risk factors for late stroke events. Additional revascularization may be considered for patients in such situations. Clinical trial registration: This study was approved by the Bioethics Review Committee of Nagoya University Hospital for the treatment and prognosis of Moyamoya disease (2016-0327).

    DOI: 10.1007/s00701-021-04773-8

    Web of Science

    Scopus

    PubMed

  31. Short-segment Internal Trapping for Symptomatic Thrombosed Large Fusiform Vertebral Artery Aneurysms (Bird’s Nest Trapping): A Technical Note

    NISHIHORI Masahiro, IZUMI Takashi, TSUKADA Tetsuya, KROPP Asuka Elisabeth, UDA Kenji, YOKOYAMA Kinya, ARAKI Yoshio, WAKABAYASHI Toshihiko

    Neurologia medico-chirurgica   Vol. 61 ( 4 ) page: 284 - 291   2021.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:The Japan Neurosurgical Society  

    <p>Internal trapping with coils is an established treatment of symptomatic large non-branching thrombosed fusiform vertebral artery aneurysms (VAA). However, when perforators arise near the aneurysm neck, parent artery occlusion has a high risk of causing medullary infarction. As an alternative treatment, we performed short-segment internal trapping of the artery using n-butyl-2-cyanoacrylate (NBCA) and coils (bird’s nest trapping). Before treatment, perianeurysmal perforators are carefully detected using high-resolution three-dimensional rotational angiography (3DRA). Double microcatheters are advanced to the distal portion of the aneurysm through a balloon guiding catheter where coils are deployed without tight packing. Then, NBCA is injected into the coil mass, taking care to preserve perforators and significant branches. The same maneuver is repeated in the proximal portion of the aneurysm. Coil placement is avoided within the middle of the aneurysm; however, if necessary, only a small number of coils are placed to prevent worsening of mass effect. Two quinquagenarian males presented with a large thrombosed fusiform VAA that caused symptoms due to mass effect. In each case, perforators arose from the parent artery and short-segment internal trapping with NBCA and coils was performed. Symptoms improved after treatment and follow-up imaging confirmed aneurysm shrinkage with no long-time recurrence. In symptomatic large fusiform VAAs where the distance from the lesion to important perforators is extremely short, internal trapping using a combination of NBCA and coils can be more useful than conventional internal trapping.</p>

    DOI: 10.2176/nmc.tn.2020-0329

    Web of Science

    Scopus

    PubMed

    CiNii Research

  32. Development and clinical evaluation of a contactless operating interface for three-dimensional image-guided navigation for endovascular neurosurgery. Reviewed International journal

    Masahiro Nishihori, Takashi Izumi, Yoshitaka Nagano, Masaki Sato, Tetsuya Tsukada, Asuka Elisabeth Kropp, Toshihiko Wakabayashi

    International journal of computer assisted radiology and surgery   Vol. 16 ( 4 ) page: 663 - 671   2021.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    PURPOSE: In endovascular neurosurgery, the operator often acquires three-dimensional (3D) images of the cerebral vessels. Although workstation reoperation is required in some situations during treatment, it leads to time loss because a sterile condition cannot be maintained and treatment must be temporarily interrupted. Therefore, a workstation reoperating system is required while maintaining the desired sterility. METHODS: A contactless operating interface using Kinect to control 3D images was developed via gesture recognition for endovascular neurosurgery and was applied to a 3D volume rendering technique (VRT) image reconstructed at the workstation. The left-hand movement determines the assigned functions, whereas the right-hand movement is used like a computer mouse to pan and zoom in/out. In addition to the interface, voice commands were used and assigned to digital operations, such as image view changes and mode signal changes. RESULTS: This system was used for the actual endovascular treatment of cerebral aneurysms and cerebral arteriovenous malformations. The operator and gesture were recognized without any problems. Using voice operation, it was possible to expeditiously set the VRT image back to the reference angle. Furthermore, it was possible to finely adjust gesture operations, including mouse operation, and treatment was completed while maintaining sterile conditions. CONCLUSION: A contactless operating interface was developed by combining the existing workstation system with Kinect and voice recognition software, allowing surgeons to perform a series of operations, which are normally performed in a console room, while maintaining sterile conditions.

    DOI: 10.1007/s11548-021-02330-3

    Web of Science

    Scopus

    PubMed

  33. Anterior Communicating Artery Aneurysm with a Peculiar Angiographic Appearance: A Case Study.

    Otawa M, Izumi T, Nishihori M, Tsukada T, Oshima R, Kawaguchi T, Goto S, Ikezawa M, Kropp AE, Wakabayashi T

    NMC case report journal   Vol. 8 ( 1 ) page: 57 - 61   2021.4

     More details

    Language:English  

    DOI: 10.2176/nmccrj.cr.2020-0036

    PubMed

  34. Analysis of relationship between superior hypophyseal artery visualization and preservation and postoperative visual field deficit in paraclinoid aneurysm

    Otawa Masato, Izumi Takashi, Nishihori Masahiro, Tsukada Tetsuya, Oshima Ryosuke, Kawaguchi Tomomi, Goto Shunsaku, Ikezawa Mizuka, Kropp Asuka Elisabeth, Araki Yoshio, Uda Kenji, Wakabayashi Toshihiko

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 83 ( 1 ) page: 21 - 30   2021.2

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    Direct surgery for paraclinoid aneurysms can result in visual field deficit owing to compromised blood flow to the superior hypophyseal artery (SHA). However, it is rarely visualized in angiography, and discussions regarding its preservation in the field of neuro-endovascular treatment are limited. Biplane angiographic suite with high spatial resolution has been used at our institution since 2014. Since then, there were a few cases where SHAs could be visualized via digital subtraction angiography. We retrospectively analyzed the relationship between the presences and abscence of SHAs in paraclinoid aneurysms and post-procedural visual field deficit. Sixty-three paraclinoid aneuryms treated by neuro-endovascular procedure in 2014-2018 at our neurosurgery department were analyzed. Pre- and post-procedural multiplanar reconstruction imagings of three-dimensional rotation angiography were analyzed to retrospectively investigate the SHAs. SHAs were visualized in 26 patients (41%) and the median number of pre-procedurally visualized SHAs was 0 (interquartile range 0-1). Their origins were the aneurysmal necks in 11 patients (42%). In two of the 11 cases, they were noticed before coil embolization and were able to be preserved after the procedure. In the remaining nine cases, they were not pre-procedurally detected, and coiling was normally conducted. Visual field deficit occurred in one of these nine cases, but symptoms were transient, and the patient fully recovered. Because SHAs could be visualized in >40% cases and no visual field defects occurred in cases that SHAs could be identified and preserved preoperatively, we recommend their preservation during coil embolization for paraclinoid aneurysms.

    DOI: 10.18999/nagjms.83.1.21

    Web of Science

    Scopus

    PubMed

  35. Direct Vertebral Artery Puncture During Open Surgery for the Endovascular Treatment of a Recurrent Vertebro-Vertebral Arteriovenous Fistula Reviewed

    Ikezawa Mizuka, Izumi Takashi, Nishihori Masahiro, Nagashima Yoshitaka, Nishimura Yusuke, Tsukuda Tetsuya, Kropp Asuka E., Goto Shunsaku, Otsuka Takafumi, Kato Naoki, Nakano Mizuki

    WORLD NEUROSURGERY   Vol. 146   page: 166 - 170   2021.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:World Neurosurgery  

    Background: Vertebro-vertebral arteriovenous fistula (VVAVF) is a condition in which there is an arteriovenous shunt directly connecting the extracranial vertebral artery to the vertebral venous plexus. Many reports have described fistula occlusion or vertebral artery trapping as treatments for VVAVF. Here, we describe a case in which endovascular treatment for recurrent VVAVF using a transfemoral approach was unsuccessful; thus, the vertebral artery (VA) was directly punctured during open surgery and the treatment was successful. Case Description: The patient was a 47-year-old female who had undergone endovascular treatment for VVAVF. The patient developed subarachnoid hemorrhage. Digital subtraction angiography revealed a left VVAVF. The left VA was trapped with coils at the C2 and C3 levels and an arteriovenous shunt formed from the VA between the 2-coil mass to the vertebral venous plexus. In addition, reflux was observed in the spinal vein. Endovascular treatment was attempted with a transfemoral approach, but we could not reach the shunt. Five days post-treatment, the patient had a second subarachnoid hemorrhage and surgery was performed to occlude the radiculomedullary vein; however, residual reflux went into the spinal vein from another spinal level. Later, the VA was directly punctured and treated with N-butyl cyanoacrylate, and the shunt disappeared. Conclusions: Direct puncture of the vertebral artery was useful in this case, where it was difficult to reach the lesion. Although direct VA puncture is associated with more complications than the transfemoral or transbrachial approach, it may be an option when other methods are difficult.

    DOI: 10.1016/j.wneu.2020.10.156

    Web of Science

    Scopus

    PubMed

  36. Case-control study of postprocedural arterial puncture site hemorrhage after neuroendovascular treatment Reviewed

    Tamari Yosuke, Izumi Takashi, Nishihori Masahiro, Imai Tasuku, Ito Masashi, Tsukada Tetsuya, Ishida Mamoru, Wakabayashi Toshihiko

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 83 ( 1 ) page: 125 - 133   2021.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Nagoya Journal of Medical Science  

    Puncture site hemorrhage following femoral artery catheterization is a significant cause of morbidity. The aim of this case-control study was to identify predictors of postprocedural arterial hemorrhage at the puncture site. We retrospectively reviewed 255 patients who underwent endovascular treatment at our institution over a 23-month period and classified them into a hemorrhage group and a non-hemorrhage group. Puncture site hemorrhage occurred in 15 patients (5.9%). Clinical factors associated with a significantly increased risk of puncture site bleeding included patients whose postoperative activated clotting time of ≤300 seconds before removal of the sheath (9 patients, 11.8%; P<0.05), those who received triple antiplatelet therapy (n<4, 17.4%; P<0.05) and the group administered heparin postoperatively (7 patients, 13.2%; P<0.05). The effects of low on-treatment platelet reactivity, i.e., P2Y12 reaction units <95%, sheath size, hemostasis method used, and operating time were not clinically significant. Our findings suggest an increased risk of puncture site hemorrhage in patients who either had an activated clotting time ≤300 seconds before the postoperative removal of the sheath, had received triple antiplatelet therapy, or were administered heparin postoperatively

    DOI: 10.18999/nagjms.83.1.125

    Web of Science

    Scopus

    PubMed

  37. Coexistence of a Dural Arteriovenous Fistula and Pial Arteriovenous Malformation Sharing a Common Drainer.

    Uda K, Izumi T, Kanamori F, Yokoyama K, Tsukada T, Nishihori M, Shintai K, Okamoto S, Araki Y

    NMC case report journal   Vol. 8 ( 1 ) page: 557 - 563   2021

     More details

    Language:English  

    DOI: 10.2176/nmccrj.cr.2020-0349

    PubMed

  38. Management of Asymptomatic Vertebral Artery Injury Caused by a Cervical Pedicle Screw Malposition: Two Case Reports.

    Otsuka T, Izumi T, Nishihori M, Tsukada T, Araki Y, Yokoyama K, Uda K, Goto S, Ikezawa M, Kato N, Nakano M, Saito R

    NMC case report journal   Vol. 8 ( 1 ) page: 713 - 717   2021

     More details

    Language:English  

    DOI: 10.2176/nmccrj.cr.2021-0062

    PubMed

  39. Levodopa-responsive Parkinsonism Caused by Recurrence of Large Basilar-tip Aneurysm after Stent-assisted Coil Embolization: A Case Report.

    Nishihori M, Izumi T, Tsukada T, Araki Y, Yokoyama K, Uda K, Wakabayashi T

    NMC case report journal   Vol. 8 ( 1 ) page: 107 - 111   2021

     More details

    Language:English  

    DOI: 10.2176/nmccrj.cr.2020-0023

    PubMed

  40. Efficacy of Respiratory Control under Local Anesthesia during Endovascular Therapy in the Tortuous Vertebral Artery with the Use of Respiratory Dislocation of the Aortic Arch

    Goto Shunsaku, Izumi Takashi, Nishihori Masahiro, Tsukada Tetsuya, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Ikezawa Mizuka

    Journal of Neuroendovascular Therapy   Vol. 15 ( 3 ) page: 195 - 199   2021

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Purpose:</b> Endovascular therapy (EVT) through the tortuous access route is increasingly performed in neurovascular procedures. In the posterior circulation through the vertebral artery (VA), ischemic complications, including vessel dissection and cerebral vessel infarction, are sometimes observed, especially during navigation of the guiding catheter, because of small vessel diameter and tortuous origin. We describe an adjunctive technique for passing the guiding catheter safely to the tortuous VA and reducing ischemic complication using respiratory displacement of the aortic arch.</p><p><b>Case Presentations:</b> The guidewire is advanced to the origin of the VA until it is caught in the tortuosity. Then we instruct the patient to take a maximum deep inspiration and hold his or her breath. In this manner, the aortic arch and side branches are dislocated to the caudal direction, which reduces the tortuosity of the VA origin and facilitates passage of the guidewire. Here, we discuss three representative cases which demonstrate that our techniques are effective in navigating the catheter to the tortuous VA.</p><p><b>Conclusion:</b> In the EVT of a patient who has a tortuous VA, respiration control under local anesthesia, maximum deep inspiration, and breath holding induce the respiratory dislocation of the aortic arch. This enables safe navigation of the guiding catheter, reduces the likelihood of interruption in blood flow, and helps avoid dissection and ischemic complications during EVT.</p>

    DOI: 10.5797/jnet.tn.2020-0109

    CiNii Research

  41. Outcomes and Issues of ‘Drip and Go’ as an Inter-Hospital Cooperation System in Mechanical Thrombectomy for Acute Ischemic Stroke

    Nishihori Masahiro, Izumi Takashi, Tsukada Tetsuya, Yokoyama Kinya, Uda Kenji, Araki Yoshio, Wakabayashi Toshihiko

    Journal of Neuroendovascular Therapy   Vol. 15 ( 10 ) page: 629 - 636   2021

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective:</b> Mechanical thrombectomy in acute ischemic stroke (AIS) has become popular in recent years. Our affiliated institutes without neuro-endovascular specialists call our department to come to assist and perform thrombectomy (Drip and Go). In this study, the effectiveness of this inter-hospital cooperative system was evaluated.</p><p><b>Methods:</b> Between January 2016 and December 2018, “Drip and Go” was performed in a total of 29 patients (20 males, average age of 75 years) from four hospitals located within a 1-hour drive, that frequently called for AIS assistance. The background and outcomes of such cases were then retrospectively collected and evaluated.</p><p><b>Results:</b> The median National Institutes of Health Stroke Scale (NIHSS) and diffusion-weighed image-Alberta Stroke Programme Early CT Score (DWI-ASPECTS) were 19 and 7, respectively. Gro in puncture was performed in 27 patients (93%) within 6 h of onset. Good reperfusion (thrombolysis in cerebral infarction [TICI] 2b/3) was obtained in 24 patients (82%) with only one patient exhibiting hemorrhagic complication. A total of 12 patients (41%) had a modified Rankin Scale (mRS) score of 0–3 after 90 days or at the time of discharge. Univariate analysis identified a DWI-ASPECTS of 7 or higher as the only significant factor associated with a good neurological prognosis (P <0.05). Neurological prognosis was the most favorable at the furthest hospital where patients had a good DWI-ASPECTS.</p><p><b>Conclusion:</b> By employing a 1-hour arrival time window and proper patient selection, the “Drip and Go” inter-hospital cooperative system can be an alternative approach for covering areas where no neuro-endovascular specialists are available for AIS.</p>

    DOI: 10.5797/jnet.oa.2020-0097

    CiNii Research

  42. An Approach to Superior Petrosal Sinus via Contralateral Superior Petrosal Sinus in a Case of Dural Arteriovenous Fistulas with Difficulty in Access

    SUZUKI Keita, NISHIHORI Masahiro, IZUMI Takashi, SUZUKI Osamu, MUTO Manabu, ARAKI Yoshio, UDA Kenji, YOKOYAMA Kinya, SAITO Ryuta

    No Kekkannai Chiryo   Vol. 6 ( 3 ) page: 161 - 168   2021

     More details

    Language:Japanese   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective</b>: Herein, we report a case of multiple dural arteriovenous fistulas (DAVFs) in the left superior petrosal sinus (SPS) successfully treated by transvenous embolization via the right SPS.</p><p><b>Case Presentation</b>: A 60-year-old woman was diagnosed with multiple DAVFs with deep venous reflux to evaluate consciousness disturbance. We performed packing of the left transverse sinus, which was chiefly involved in reflux to the straight sinus. However, consciousness continued to be mildly disturbed, and DSA was performed again. A shunt was inserted into the left SPS, and the subsequently occurring deep venous reflux was clearly revealed. Because the ipsilateral transverse sinus and both inferior petrosal sinuses were already occluded and unavailable as access routes, we used the contralateral SPS and both cavernous sinuses to navigate the microcatheter into the shunt. We achieved occlusion of the SPS and stopped the reflux by inserting the intermediate catheter firmly into the bilateral SPS.</p><p><b>Conclusion</b>: An access route through the contralateral SPS might successfully enable transvenous embolization of DAVF cases without an ipsilateral access route.</p>

    DOI: 10.20626/nkc.tn.2021-0009

    CiNii Research

  43. A Case of Two Times Parturition by Caesarean Section after Stent-assisted Coil Embolization for the Ruptured Basilar Trunk Artery Aneurysm

    KATO Naoki, IZUMI Takashi, NISHIHORI Masahiro, TSUKADA Tetsuya, ARAKI Yoshio, YOKOYAMA Kinya, UDA Kenji, MATSUBARA Noriaki, KOKETSU Naoki

    No Kekkannai Chiryo   Vol. 6 ( 1 ) page: 24 - 29   2021

     More details

    Language:Japanese   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective:</b> With the widespread use of endovascular treatment for cerebral aneurysms, women of childbearing age may also undergo this treatment. We report the case of a patient who underwent stent-assisted coil embolization for a ruptured large basilar artery aneurysm after two successful subsequent childbirths.</p><p><b>Case Presentation:</b> A 27-year-old woman developed a subarachnoid hemorrhage due to a ruptured basilar artery aneurysm (maximum diameter, 24 mm). We performed stent-assisted coil embolization. She became pregnant through in vitro fertilization (IVF) at age 33 years when she was already off the antiplatelet medication. She resumed taking aspirin when she found out that she was pregnant and switched to subcutaneous injection of heparin for 28 weeks. She gave birth by cesarean section at 37 weeks, without complications. She became pregnant through IVF again at age 35 years, received the same antithrombotic treatment, and gave birth without complications.</p><p><b>Conclusion:</b> There are no clear criteria for antithrombotic treatment in pregnant patients after the implantation of a cerebral aneurysm-assisted stent. However, the patient in this reported case passed the perinatal period with antithrombotic therapy without complications.</p>

    DOI: 10.20626/nkc.cr.2020-0019

    CiNii Research

  44. [Ruptured Spinal Arteriovenous Malformation Mimicking Bacterial Meningitis:A Case Report]. Reviewed

    Hiramatsu T, Nishihori M, Haraguchi K, Okada T, Endo O, Fujii K, Yokoyama H, Takayanagi K, Yamamoto N

    No shinkei geka. Neurological surgery   Vol. 48 ( 11 ) page: 1051 - 1057   2020.11

     More details

    Authorship:Corresponding author   Language:Japanese   Publishing type:Research paper (scientific journal)  

    DOI: 10.11477/mf.1436204319

    PubMed

  45. A case of internal trapping to a thrombosed giant rapidly growing aneurysm at the posterior cerebral artery

    Otawa Masato, Izumi Takashi, Nishihori Masahiro, Tsukada Tetsuya, Oshima Ryosuke, Kawaguchi Tomomi, Goto Shunsaku, Ikezawa Mizuka, Kropp Asuka Elisabeth, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Wakabayashi Toshihiko

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 82 ( 3 ) page: 557 - 566   2020.8

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    We describe a case of internal trapping including the vasa vasorum for a thrombosed giant rapidly growing posterior cerebral artery aneurysm and performing a detailed analysis. A 48-year-old woman was followed up in our hospital for a thrombosed large posterior cerebral artery aneurysm located in the P2 segment. She initially presented after experiencing a sudden headache on two occasions. Head computed tomography and magnetic resonance imaging indicated a larger aneurysm than before. Digital subtraction angiography with balloon occlusion test was assessed, and internal trapping was sequentially conducted. We detected that the vasa vasorum originated from the posterior temporal artery. Therefore, we embolized the posterior temporal artery including the vasa vasorum using N-butyl-2-cyanoacrylate and Lipiodol. Next, the anterior temporal artery was embolized with N-butyl-2-cyanoacrylate and Lipiodol, posterior temporal artery P3 segment and the aneurysm and finally the proximal P2 segment were embolized with coils. Final vertebral and internal carotid angiography showed complete obliteration of the aneurysm. On the day after the procedure her paresis worsened and she developed left upper quadrantanopia, however was finally discharged with no hemiparesis. We reported a case of a rapidly growing thrombosed giant posterior cerebral artery aneurysm treated by parent artery occlusion including the vasa vasorum with detailed image analysis.

    DOI: 10.18999/nagjms.82.3.557

    Web of Science

    Scopus

    PubMed

  46. Surgical Designs of Revascularization for Moyamoya Disease: 15 Years of Experience in a Single Center

    Araki Yoshio, Uda Kenji, Yokoyama Kinya, Kanamori Fumiaki, Mamiya Takashi, Nishihori Masahiro, Izumi Takashi, Tanahashi Kuniaki, Masaki Sumitomo, Sho Okamoto, Wakabayashi Toshihiko, Natsume Atsushi

    WORLD NEUROSURGERY   Vol. 139   page: E325 - E334   2020.7

     More details

    Language:English   Publisher:World Neurosurgery  

    Objective: Cerebral revascularization surgery has been established as an effective treatment for moyamoya disease. On the other hand, harvesting grafts and tissues to nourish the scalp may increase the risk of postoperative wound-related complications. The purpose of this study was to clarify risk factors for wound-related complications after examining the relationship with the surgical design. Methods: We retrospectively analyzed 115 patients who underwent 197 revascularization procedures between October 2004 and March 2019. The design of the revascularization was classified into 6 types, then further classified according to the number of grafts harvested, resulting in 11 subtypes. Incidences of minor and major wound-related complications for the 11 different surgical designs were assessed. The risk of complications from each design was statistically examined. In addition, the yearly transition rate of complications was also investigated. Results: Wound-related complications occurred in 38 of the 195 operations (19.5%), including 10 major events (26.3%) and 28 minor events (73.7%). Significant differences in the incidence of complications were seen according to surgical design (P < 0.05), with complications significantly more frequent for L(a) double type and L(p) double type and less frequent for L(a) single type and L(p) single type. In addition, significant differences were found in the incidence and degree of complications according to the number of grafts (0–2) (P < 0.05). The incidence of wound-related complications has clearly decreased since 2015. Conclusions: Wound-related complications were more frequent and tended to become more severe with double-bypass procedures but were clearly improved under a plastic surgery approach.

    DOI: 10.1016/j.wneu.2020.03.217

    Web of Science

    Scopus

    PubMed

  47. Endovascular Therapy for Intracranial Artery Stenosis: Results from the Japanese Registry of Neuroendovascular Therapy (JR-NET)3.

    Izumi T, Nishihori M, Imamura H, Iihara K, Sakai N, JR-NET investigators

    Neurologia medico-chirurgica   Vol. 60 ( 5 ) page: 256 - 263   2020.5

     More details

    Language:English  

    DOI: 10.2176/nmc.oa.2019-0271

    PubMed

  48. Brain Compression by Encephalo-Myo-Synangiosis is a Risk Factor for Transient Neurological Deficits After Surgical Revascularization in Pediatric Patients with Moyamoya Disease Reviewed

    Kanamori Fumiaki, Araki Yoshio, Yokoyama Kinya, Uda Kenji, Nishihori Masahiro, Izumi Takashi, Okamoto Sho, Wakabayashi Toshihiko

    WORLD NEUROSURGERY   Vol. 133   page: E558 - E566   2020.1

     More details

    Language:English   Publisher:World Neurosurgery  

    Objective: In pediatric patients with moyamoya disease, the pathophysiology of transient neurological deficits and the clinical features of perioperative cerebral blood flow (CBF) changes are unclear. The purpose of this study was to investigate the risk factors of postoperative transient neurological deficits and identify predictors of perioperative CBF changes. Methods: This retrospective study included 42 surgical procedures in 28 pediatric patients who underwent surgical revascularization for moyamoya disease, including encephalo-myo-synangiosis (EMS) with or without superficial temporal artery–middle cerebral artery (MCA) anastomosis. Magnetic resonance images and single photon emission computed tomography results were obtained. Brain compression by EMS was also checked in fluid attenuated inversion recovery images. Using single photon emission computed tomography, CBF was measured at each anterior and posterior part of the MCA region. Results: Postoperative transient neurological deficits were observed in 12 (28.6%) out of 42 surgical procedures. Brain compression by EMS was a significant risk for transient neurological deficits (P = 0.009). The postoperative CBF in the anterior region increased in 9 cases (21.4%) and decreased in 10 cases (23.8%); in the posterior region, it increased in 12 cases (28.6%) and decreased in 10 cases (23.8%). Preoperative CBF of the anterior region was significantly related to both perioperative CBF changes in the MCA regions (anterior part, P = 0.004; posterior part, P = 0.025). Conclusions: Brain compression by EMS is a risk factor for postoperative transient neurological deficits in pediatric patients with moyamoya disease, and preoperative CBF of the anterior MCA region could predict perioperative CBF change in the MCA regions.

    DOI: 10.1016/j.wneu.2019.09.093

    Web of Science

    Scopus

    PubMed

  49. Thrombosis of great vein of Galen caused by Factor XIII concentrate: A case report

    Nakano Mizuki, Araki Yoshio, Kanamori Fumiaki, Uda Kenji, Yokoyama Kinya, Nishihori Masahiro, Izumi Takashi, Yoshimoto Masayuki

    Japanese Journal of Stroke   Vol. 42 ( 3 ) page: 196 - 202   2020

     More details

    Language:Japanese   Publisher:The Japan Stroke Society  

    <p>We report our experience of great vein of Galen thrombosis after treatment consisted of Factor XIII (F XIII) concentrate. A 76-year-old woman presented with subarachnoid hemorrhage (SAH) caused by ruptured anterior communicating artery aneurysm and was successfully treated with direct surgery. Four days after operation, she was awake but presented with cerebrospinal fluid rhinorrhea and was found to be F XIII deficiency, therefore we performed intravenous injection of F XIII concentrate. Sixteen days after operation, she became drowsy without cerebrovascular spasms and hydrocephalus. CT angiography and digital subtraction angiography demonstrated the obstruction of great vein of Galen. She received the treatment with low-molecular-weight heparin (LMWH) and after that, direct oral anticoagulants (DOAC). The patient responded to the treatment, and followed an uneventful course without developing any hemorrhagic complication. To the best of our knowledge, this is the first case of cerebral venous thrombosis after the treatment of F XIII concentrate. The thrombosis can be attributed to the treatment of F XIII concentrate, and would be better served by treatment with LMWH and DOAC.</p>

    DOI: 10.3995/jstroke.10720

    CiNii Research

  50. Factors influencing blood flow resistance from a large internal carotid artery aneurysm revealed by a computational fluid dynamics model

    Imai Tasuku, Izumi Takashi, Isoda Haruo, Ishiguro Kenta, Mizuno Takashi, Tsukada Tetsuya, Kropp Asuka, Ito Masashi, Nishihori Masahiro, Ishida Mamoru, Tamari Yosuke, Wakabayashi Toshihiko

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 81 ( 4 ) page: 629 - 636   2019.11

     More details

    Language:English   Publisher:Nagoya Journal of Medical Science  

    Hyperperfusion syndrome occurs after treatment of a large or giant cerebral aneurysm. Recently, flow-diverter stent placement has emerged as an effective treatment method for a large cerebral aneurysm, but postoperative ipsilateral delayed intraparenchymal hemorrhage occurs in a minority of cases. The mechanism underlying delayed intraparenchymal hemorrhage is not established, but one possibility is hyperperfusion syndrome. The incidence of delayed intraparenchymal hemorrhage appears to be higher for giant aneurysms; hence, we speculated that large/giant aneurysms may create flow resistance, and mitigation by flow-diverter stent deployment leads to hyperperfusion syndrome and delayed intraparenchymal hemorrhage. The purpose of this study was to identify aneurysm characteristics promoting flow resistance by the analysis of pressure loss in an internal carotid artery paraclinoid aneurysm model using computational fluid dynamics. A virtual U-shaped model of the internal carotid artery siphon portion was created with a spherical aneurysm of various angles, body diameters, and neck diameters. Visualization of streamlines, were calculated of pressure loss between proximal and distal sides of the aneurysm, and vorticity within the aneurysm were calculated. The pressure loss and vorticity demonstrated similar changes according to angle, peaking at 60°. In contrast, aneurysm diameter had little influence on pressure loss. Larger neck width, however, increases pressure loss. Our model predicts that aneurysm location and neck diameter can increase the flow resistance from a large internal carotid artery aneurysm. Patients with large aneurysm angles and neck diameters may be at increased risk of hyperperfusion syndrome and ensuing delayed intraparenchymal hemorrhage following flow-diverter stent treatment.

    DOI: 10.18999/nagjms.81.4.629

    Web of Science

    Scopus

    PubMed

  51. Cardiac arrest induced by carotid sinus reflex activation during flow-diverter stent deployment.

    Goto S, Izumi T, Nishihori M, Ishida M, Ishida T, Otawa M, Kawaguchi T, Oshima R, Kropp A, Ikezawa M, Wakabayashi T

    World neurosurgery   Vol. 124   page: 22 - 24   2019.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.wneu.2018.12.136

    Web of Science

    Scopus

    PubMed

  52. Intraoperative evaluation of local cerebral hemodynamic change by indocyanine green videoangiography: prediction of incidence and duration of postoperative transient neurological events in patients with moyamoya disease. International journal

    Kenji Uda, Yoshio Araki, Shinsuke Muraoka, Shinji Ota, Kentaro Wada, Kinya Yokoyama, Masahiro Nishihori, Takashi Izumi, Sho Okamoto, Toshihiko Wakabayashi

    Journal of neurosurgery   Vol. 130 ( 4 ) page: 1367 - 1375   2019.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    OBJECTIVETransient neurological events (TNEs) occur frequently in the acute phase after direct bypass surgery for moyamoya disease (MMD), but there is currently no way to predict them. FlowInsight is a specialized software for analyzing indocyanine green (ICG) videoangiography taken with a surgical microscope. The purpose of this study was to investigate whether intraoperative evaluation of local hemodynamic changes around anastomotic sites using FlowInsight could predict the incidence and duration of TNEs.METHODSFrom patients who were diagnosed with MMD in our hospital between August 2014 and March 2017 and who underwent superficial temporal artery-middle cerebral artery bypass surgery, we investigated 25 hemispheres (in 22 patients) in which intraoperative ICG analysis was performed using FlowInsight. To evaluate the local cerebral hemodynamics before and after anastomosis, regions of interest were set at 3 locations on the brain surface around the anastomotic site, and the mean cerebral blood flow (CBF), mean gradation (Grad), mean transit time (MTT), and mean time to peak (TTP) were calculated from the 3 regions of interest. Furthermore, the change rate in CBF (ΔCBF [%]) was calculated using the formula (postanastomosis mean CBF - preanastomosis mean CBF)/preanastomosis mean CBF. ΔGrad (%), ΔMTT (%), and ΔTTP (%) were similarly calculated.RESULTSPostoperative stroke without TNE occurred in 2 of the 25 hemispheres. These 2 hemispheres (in 2 patients) were excluded from the study, and data from the remaining 23 hemispheres (in 20 patients) were analyzed. For each parameter (ΔCBF, ΔGrad, ΔMTT, and ΔTTP) calculated by FlowInsight, the difference between the groups with and without TNEs was significant. The median values for ΔCBF and ΔGrad were significantly higher in the TNE group than in the no-TNE group (ΔCBF 30.13 vs 3.54, p = 0.0106; ΔGrad 62.05 vs 10.78, p = 0.00435), whereas the median values for ΔMTT and ΔTTP were significantly lower in the TNE group (ΔMTT -16.90 vs -7.393, p = 0.023; ΔTTP -29.07 vs -7.02, p = 0.00342). Comparison of the area under the curve (AUC) for each parameter showed that ΔTTP had the highest AUC and was the parameter with the highest diagnostic accuracy (AUC 0.857). The Youden index revealed that the optimal cutoff value of ΔTTP was -11.61 (sensitivity 77.8%, specificity 71.4%) as a predictor of TNEs. In addition, Spearman's rank correlation coefficients were calculated, and ΔCBF, ΔGrad, ΔMTT, and ΔTTP each showed a strong correlation with the duration of TNEs. The larger the change in each parameter, the longer the TNEs persisted.CONCLUSIONSIntraoperative ICG videoangiography findings were correlated with the occurrence and duration of TNEs after direct bypass surgery for MMD. Screening for cases at high risk of TNEs can be achieved by ICG analysis using FlowInsight.

    DOI: 10.3171/2017.10.JNS171523

    Web of Science

    Scopus

    PubMed

  53. Experimental study of the characteristics of various types of filling coils for intracranial aneurysm embolisation

    Ito Masashi, Matsubara Noriaki, Izumi Takashi, Miyachi Shigeru, Ota Keisuke, Imai Tasuku, Nishihori Masahiro, Wakabayashi Toshihiko

    INTERVENTIONAL NEURORADIOLOGY   Vol. 24 ( 5 ) page: 513 - 519   2018.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1177/1591019918779196

    Web of Science

    Scopus

    PubMed

  54. Association between CYP2C19 genotype and the additional effect of cilostazol to clopidogrel resistance in neuroendovascular therapy

    Hayato Tajima, Takashi Izumi, Shigeru Miyachi, Noriaki Matsubara, Masashi Ito, Tasuku Imai, Masahiro Nishihori, Kazunori Shintai, Sho Okamoto, Yoshio Araki, Yasuo Kumakura, Yoko Furukawa-Hibi, Kiyofumi Yamada, Toshihiko Wakabayashi

    Nagoya Journal of Medical Science   Vol. 80 ( 2 ) page: 207 - 215   2018.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Nagoya University  

    We investigated the association between CYP2C19 genotype and additional effect of cilostazol on clopidogrel resistance (CR) in neuroendovascular therapy. Between January 2012 and January 2016, 447 consecutive patients were administered with 75-mg cilostazol/day. The VerifyNow System was used for evaluating P2Y12 reaction units (PRU) &gt
    230 and/or percentage inhibition of platelet function (% Inhibition) ≤ 20 as CR. Among 158 patients with CR, 31 were administered with additional 100- or 200-mg cilostazol/day and their platelet function was evaluated. According to CYP2C19 genotypes revealed using the Spartan RX and DNeasy Blood &amp
    Tissue Kit, patients were classified into three phenotypic groups: extensive metabolizer (EM, three patients), intermediate metabolizer (IM, 12 patients), and poor metabolizer (PM, 16 patients). Administration of additional cilostazol decreased PRU (EM group: 160.7 ± 85.2 after vs 278.3 ± 40.1 before, P = 0.15
    IM group: 205.6 ± 74.0 vs 254.3 ± 35.0, P = 0.02
    and PM group: 227.8 ± 52.2 vs 282.1 ± 30.4, P = 0.003), and increased % Inhibition (EM group: 40.0 ± 27.9 vs 9.3 ± 3.8, P = 0.25
    IM group: 31.4 ± 18.0 vs 11.8 ± 8.2, P = 0.001
    and PM group: 24.6 ± 15.0 vs 10.4 ± 9.3, P = 0.001). However, the rate of normalized-clopidogrel response, thromboembolic lesions, and bleeding complications were not significantly different among the three groups. Thus, the addition of cilostazol was effective on CR in terms of PRU, % Inhibition, rate of change of normalized-clopidogrel response, thromboembolic events, and bleeding complications irrespective of phenotype.

    DOI: 10.18999/nagjms.80.2.207

    Scopus

    PubMed

  55. Association between CYP2C19 genotype and the additional effect of cilostazol to clopidogrel resistance in neuroendovascular therapy

    Tajima Hayato, Izumi Takashi, Miyachi Shigeru, Matsubara Noriaki, Ito Masashi, Imai Tasuku, Nishihori Masahiro, Shintai Kazunori, Okamoto Sho, Araki Yoshio, Kumakura Yasuo, Furukawa-Hibi Yoko, Yamada Kiyofumi, Wakabayashi Toshihiko

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 80 ( 2 ) page: 207-215   2018.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.18999/nagims.80.2.207

    Web of Science

  56. Evaluation for shunted pouches of cavernous sinus dural arteriovenous fistula and the treatment outcome of transvenous embolization

    Masaki Sato, Takashi Izumi, Noriaki Matsubara, Masahiro Nishihori, Shigeru Miyachi, Toshihiko Wakabayashi

    Interventional Neuroradiology   Vol. 24 ( 2 ) page: 189 - 196   2018.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SAGE Publications Inc.  

    Background: This study aimed to evaluate the detailed location and the number (single or multiple) of cavernous sinus dural arteriovenous fistula (CSDAVF) shunted pouches as well as the relationship between the characteristics of shunted pouch(es) and the treatment outcome of transvenous embolization for CSDAVF. Methods: A total of 23 consecutive patients with CSDAVFs who underwent angiogram and transvenous embolization were retrospectively analyzed. Shunted pouches were assessed using three-dimensional angiogram and multiplanar reformatted image obtained from the rotational angiogram data. Results: Of the 23 patients with CSDAVFs, 40 shunted pouches were identified. Twelve CSDAVFs had a single shunted pouch, and 11 had multiple shunted pouches. The mean CSDAVF with multiple shunted pouches was 2.5. The shunted pouches were more often found in the posterior compartment of the CS, which was connected with the intercavernous sinus (23/40
    57.5%). In 12 CSDAVFs with a single shunted pouch, 10 were treated with selective embolization and complete occlusion was achieved during the follow-up. Two CSDAVFs with single shunted pouch were just observed without intervention, and DAVFs disappeared spontaneously during the follow-up period. In 11 CSDAVFs with multiple shunted pouches, eight were treated with selective embolization and three with sinus embolization. In six of eight (75%), complete occlusion was achieved following selective embolization, but two of eight (25%) recurred and required retreatment. Conclusions: Rotational angiography data suggested that the shunted pouches of CSDAVFs were mostly located in the posterior compartment of the CS connected with the intercavernous sinus. Selective embolization for CSDAVFs with a single shunted pouch is the first-line treatment alternative to sinus packing, and selective embolization with multiple shunted pouches will be a considerable treatment option.

    DOI: 10.1177/1591019917743064

    Web of Science

    Scopus

    PubMed

  57. Cortical-Sulcal Hyperintensity in Fluid-attenuated Inversion Recovery Images and Postoperative Transient Neurological Events after Indirect Revascularization Surgery for Moyamoya Disease

    ARAKI Yoshio, OKAMOTO Sho, YOKOYAMA Kinya, OTA Shinji, UDA Kenji, MURAOKA Shinsuke, KANAMORI Fumiaki, NISHIHORI Masahiro, IZUMI Takashi, WAKABAYASHI Toshihiko

    Surgery for Cerebral Stroke   Vol. 46 ( 6 ) page: 439 - 444   2018

     More details

    Language:Japanese   Publisher:The Japanese Society on Surgery for Cerebral Stroke  

    Transient neurological events (TNEs) are relatively common phenomena after superficial temporal artery-middle cerebral artery (STA-MCA) bypass for the surgical treatment of moyamoya disease. Cortical-sulcal hyperintensity (CSHI) signs in magnetic resonance imaging (MRI) fluid-attenuated inversion recovery (FLAIR) images during the acute stage after the surgery have also been reported. These symptoms and radiological findings are reportedly correlated; however, few studies have examined these characteristics after indirect vascularization surgery. Therefore, here we retrospectively investigated the incidence and correlation of this issue. The CSHI signs were observed in 10 of 16 hemispheres (62.5%), and TNEs after the surgery were recognized in nine (56.3%). This correlation was statistically significant (p = 0.01). Our findings indicate that CSHI signs are associated with direct and indirect bypass surgery and may be closely related to postoperative TNEs.

    DOI: 10.2335/scs.46.439

    CiNii Research

  58. Clinical Application of Insertion Force Sensor System for Coil Embolization of Intracranial Aneurysms

    Noriaki Matsubara, Shigeru Miyachi, Takashi Izumi, Hiroyuki Yamada, Naoki Marui, Keisuke Ota, Hayato Tajima, Kazunori Shintai, Masashi Ito, Tasuku Imai, Masahiro Nishihori, Toshihiko Wakabayashi

    WORLD NEUROSURGERY   Vol. 105   page: 857 - 863   2017.9

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:ELSEVIER SCIENCE INC  

    INTRODUCTION: In endovascular embolization for intracranial aneurysms, it is important to properly control the coil insertion force. However, the force can only be subjectively detected by the subtle feedback experienced by neurointerventionists at their fingertips. The authors envisioned a system that would objectively sense and quantify that force. In this article, coil insertion force was measured in cases of intracranial aneurysm using this sensor, and its actual clinical application was investigated.
    METHODS: The sensor consists of a hemostatic valve (Y-connector). A little flexure was intentionally added in the device, and it creates a bend in the delivery wire. The sensor measures the change in the position of the bent wire depending on the insertion force and translates it into a force value. Using this, embolization was performed for 10 unruptured intracranial aneurysms.
    RESULTS: The sensor adequately recorded the force, and it reflected the operators' usual clinical experience. The presence of the sensor did not affect the procedures. The sensor enabled the operators to objectively note and evaluate the insertion force and better cooperative handling was possible. Additionally, other members of the intervention team shared the information. Force records demonstrated the characteristic patterns according to every stage of coiling (framing, filling, and finishing).
    CONCLUSIONS: The force sensor system adequately measured coil insertion force in intracranial aneurysm coil embolization procedures. The safety of this sensor was demonstrated in clinical application for the limited number of patients. This system is useful adjunct for assisting during coil embolization for an intracranial aneurysm.

    DOI: 10.1016/j.wneu.2017.06.092

    Web of Science

    Scopus

    PubMed

  59. Coiling of a Ruptured Large Internal Carotid Artery Aneurysm via Extracranial-Intracranial Saphenous Vein Bypass Graft Just After Proximal Ligation of the Internal Carotid Artery

    Hayato Tajima, Yoshio Araki, Takashi Izumi, Masahiro Nishihori, Sho Okamoto, Toshihiko Wakabayashi

    WORLD NEUROSURGERY   Vol. 98   page: 879.e1 - 879.e4   2017.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:ELSEVIER SCIENCE INC  

    BACKGROUND: Combined direct and endovascular surgery has been performed to treat large to giant internal carotid artery (ICA) aneurysms. This report describes successful treatment of a large ICA aneurysm by coiling of the aneurysm via an extracranial-intracranial saphenous vein (SV) graft just after bypass and ICA proximal ligation.
    CASE DESCRIPTION: A 66-year-old woman presented with a left ICA supraclinoid aneurysm with progressive visual field defect and impaired visual acuity in the left eye. While waiting for scheduled surgery, she experienced a subarachnoid hemorrhage. An extracranial-intracranial high-flow bypass using an SV graft and proximal ligation of the ICA were performed. Coiling of the aneurysm was immediately performed successfully via the SV bypass graft. The patient experienced no new neurologic deficit after this treatment. Follow-up radiologic evaluations using magnetic resonance imaging and magnetic resonance angiography revealed complete aneurysm occlusion.
    CONCLUSIONS: Aneurysm coiling via an extracranial-intracranial SV bypass graft could offer an alternative when an antegrade access route to the ICA is not used because of prior parent artery ligation.

    DOI: 10.1016/j.wneu.2016.11.066

    Web of Science

    Scopus

    PubMed

  60. The Treatment Outcome of Transarterial Embolization for Isolated Sinus Type Dural Arteriovenous Fistula between NBCA and Onyx

    Imai Tasuku, Izumi Takashi, Matsubara Noriaki, Nishihori Masahiro, Ito Masashi, Sato Masaki, Tamari Yosuke, Ishida Mamoru, Tsukada Tetsuya, Miyachi Shigeru, Wakabayashi Toshihiko

    Journal of Neuroendovascular Therapy   Vol. 11 ( 6 ) page: 279 - 287   2017

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective:</b> The purpose of this study was to compare the clinical outcome of transarterial embolization for isolated sinus type dural arteriovenous fistula (iDAVF) using n-butyl-cyanoacrylate (NBCA) and Onyx.</p><p><b>Methods:</b> Seventeen lesions of iDAVF in 17 patients who underwent transarterial embolization between March 2008 and February 2015 were retrospectively analyzed. They were treated by embolization using NBCA in 10 patients, Onyx in 5 patients, and combination of NBCA and Onyx in 2 patients. We compared the results between embolization with NBCA and Onyx as follows: complete occlusion rate, number of embolized vessels, procedure-related complications, treatment time, dose of radiation exposure, amount of contrast agent, and total cost of the devices.</p><p><b>Results:</b> The complete occlusion rate of iDAVF was significantly higher in the Onyx group: 4 of 10 (40%) in NBCA and 5 of 5 (100%) in Onyx (P = 0.04). The number of treated vessels (5.1 ± 1.2 in NBCA, 1 in Onyx [P <0.001]), the maximum skin entrance dose (NBCA: 5030 ± 1646 [mGy], Onyx: 1670 ± 564 [mGy] in Onyx [P <0.01]), and total cost of the devices (601,265 ± 15,749 [yen] in NBCA, 374,210 ± 122,142 [yen] in Onyx [P <0.01]) were significantly higher in the NBCA. No significant difference was observed in the treatment time and contrast agent dose.</p><p><b>Conclusion:</b> In transarterial embolization of iDAVF, a higher complete occlusion rate was obtained with Onyx, which was also advantageous for reducing the exposure dose and cost of the devices.</p>

    DOI: 10.5797/jnet.oa.2016-0090

    CiNii Research

  61. A Case of Lateral Medullary Artery Arisen from the Posterior Meningeal Artery

    Ito Masashi, Izumi Takashi, Nishihori Masahiro, Imai Tasuku, Tamari Yousuke, Tsukada Tetsuya, Ishida Mamoru, Kropp Asuka, Wakabayashi Toshihiko

    Journal of Neuroendovascular Therapy   Vol. 11 ( 12 ) page: 615 - 618   2017

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective:</b> We encountered a patient with lateral medullary infarction during transarterial embolization of the posterior meningeal artery (PMA). We reviewed the anatomic characteristics/imaging findings of this disorder.</p><p><b>Case Presentation:</b> A 69-year-old male. Cerebral infarction involving the lateral medulla occurred during transarterial embolization of a dural arteriovenous fistula. It was considered to be a complication related to occlusion of a lateral medulla-penetrating vessel on microcatheter/guidewire operations in the PMA. When examining images in detail, the blood vessel could be confirmed using DSA and 3D angiography.</p><p><b>Conclusion:</b> When performing embolization, the presence of a brainstem-penetrating vessel originating from the PMA must be considered.</p>

    DOI: 10.5797/jnet.cr.2017-0038

    CiNii Research

  62. Ruptured blood blister-like ICA aneurysm that detailed diagnostic imaging was useful in determining the therapeutic strategy: a case report

    Nishihori Masahiro, Izumi Takashi, Matsubara Noriaki, Uda Kenji, Shintai Kazunori, Tajima Hayato, Ito Masashi, Imai Tasuku, Wakabayashi Toshihiko

    Japanese Journal of Stroke   Vol. 39 ( 1 ) page: 24 - 28   2017

     More details

    Language:Japanese   Publisher:The Japan Stroke Society  

    A 38 year-old woman with a sudden headache was transferred to the ER. Head CT and CT angiography (CTA) revealed subarachnoid hemorrhage without any aneurysm. Multimodality examinations were performed repeatedly during the acute period. On her 14th hospital day, digital subtraction angiography showed a slight protruded change of the right internal carotid artery (C3 portion), which was suspected as a blood blister-like aneurysm. As a result of comparing the MRI and CTA images, the false lumen was speculated to spread around the posterior wall of the ophthalmic artery bifurcation. Balloon occlusion test showed tolerance, however, no intraorbital blood flow was observed through any angiographies during ICA occlusion. We changed the strategy to the stent assisted coil embolization with preserved ophthalmic artery flow because trapping of dissecting lesion carried a very high risk of visual impairment. After this embolization, there was good course with no neurological deterioration, no blurred vision, and no recurrence of this aneurysm. As for the present patient, diagnostic multimodality imaging with MRI and angiography seemed to not only change the determination of therapeutic strategy but also avoid complication risk.

    DOI: 10.3995/jstroke.10412

    CiNii Research

  63. Treatment protocol based on assessment of clot quality during endovascular thrombectomy for acute ischemic stroke using the Trevo stent retriever Reviewed

    Kojiro Ishikawa, Tomotaka Ohshima, Masahiro Nishihori, Tasuku Imai, Shunsaku Goto, Taiki Yamamoto, Toshihisa Nishizawa, Shinji Shimato, Kyozo Kato

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 78 ( 3 ) page: 255 - 265   2016.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:NAGOYA UNIV, SCH MED  

    The optional endovascular approach for acute ischemic stroke is unclear. The Trevo stent retriever can be used as first-line treatment for fast mechanical recanalization. The authors developed a treatment protocol for acute ischemic stroke based on the assessment of clot quality during clot removal with the Trevo. This prospective single-center study included all patients admitted for acute ischemic stroke between July 2014 and February 2015, who underwent emergency endovascular treatment. According to the protocol, the Trevo was used for first-line treatment. Immediately after the Trevo was deployed, the stent delivery wire was pushed to open the stent by force (ACAPT technique). Clot quality was assessed on the basis of the perfusion status after deployment of the Trevo; continued occlusion or immediate reopening either reoccluded or maintained after the stent retriever had been in place for 5 min. If there was no obvious clot removal after the first pass with the Trevo, according to the quality of the clot, either a second pass was performed or another endovascular device was selected. Twelve consecutive patients with acute major cerebral artery occlusion were analyzed. Thrombolysis in cerebral infarction score 2b and 3 was achieved in 11 patients (91.7%) and 9 (75%) had a good clinical outcome after 90 days based on a modified Rankin scale score &lt;= 2. Symptomatic intracranial hemorrhage occurred in 1 patient (8.3%). The overall mortality rate was 8.3%. Endovascular thrombectomy using the Trevo stent retriever for first-line treatment is feasible and effective.

    Web of Science

  64. Overlap stenting for in-stent restenosis after carotid artery stenting Reviewed

    Masahiro Nishihori, Tomotaka Ohshima, Taiki Yamamoto, Shunsaku Goto, Toshihisa Nishizawa, Shinji Shimato, Takashi Izumi, Kyozo Kato

    NAGOYA JOURNAL OF MEDICAL SCIENCE   Vol. 78 ( 2 ) page: 143 - 149   2016.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:NAGOYA UNIV, SCH MED  

    Our aim was to assess the clinical safety and efficacy of overlap stenting for in-stent restenosis after carotid artery stenting. The study was conducted between July 2008 and February 2015. A database of consecutive carotid artery stenting procedures was retrospectively assessed to identify the cases of in-stent restenosis that were treated with overlap stenting under proximal or distal protection. The clinical and radiological records of the patients were then reviewed. Of the 155 CAS procedures in 149 patients from the database, 6 patients met the inclusion criteria. All the 6 patients were initially treated with moderate dilatation because of the presence of an unstable plaque. The technical success rate of the overlap stenting was 100%, with no 30-day mortality or morbidity. In addition, there was no further in-stent restenosis during a follow-up period of over 12 months. These results indicated that overlap stenting for in-stent restenosis after carotid artery stenting was both safe and effective in our cohort.

    Web of Science

  65. Overlap stenting for in-stent restenosis after carotid artery stenting.

    Nishihori M, Ohshima T, Yamamoto T, Goto S, Nishizawa T, Shimato S, Izumi T, Kato K

    Nagoya journal of medical science   Vol. 78 ( 2 ) page: 143 - 9   2016.5

     More details

    Language:English  

    PubMed

  66. Overlap stenting for in-stent restenosis after carotid artery stenting

    Nishihori Masahiro, Ohshima Tomotaka, Yamamoto Taiki, Goto Shunsaku, Nishizawa Toshihisa, Shimato Shinji, Izumi Takashi, Kato Kyozo

    Nagoya Journal of Medical Science   Vol. 78 ( 2 ) page: 143 - 149   2016.5

     More details

    Language:English   Publisher:Nagoya University Graduate School of Medicine, School of Medicine  

    DOI: 10.18999/nagjms.78.2.143

  67. Comparison of Clinical Outcomes Using 10 Coil Versus 14 Coil in Endovascular Coil Embolization for Small and Medium-sized Intracranial Aneurysms: Efficacy of 14 Coil

    Imai Tasuku, Ohshima Tomotaka, Goto Shunsaku, Yamamoto Taiki, Shimato Shinji, Nishizawa Toshihisa, Kato Kyozo, Nishihori Masahiro, Izumi Takashi, Wakabayashi Toshihiko

    Journal of Neuroendovascular Therapy   Vol. 10 ( 4 ) page: 196 - 200   2016

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective:</b> The purpose of this retrospective study was to compare the therapeutic results of middle-sized or small cerebral aneurysms coiling using 10 coil (thickness, 0.0095 inch–0.012 inch) and 14 coil (thickness, 0.0135 inch) as a complex framing coil.</p><p><b>Methods:</b> Fifty aneurysms (maximum size, 4 mm–10 mm) in 50 patients treated in our hospital between May 2012 and May 2015 were assigned in this study. We compared the volume embolization rate, recurrence rate, initial occlusion grade between 14 coil (25 aneurysms) and 10 coil (25 aneurysms).</p><p><b>Results:</b> The mean volume embolization ratio was significantly higher (14 coil 37.5 ± 8.8%, 10 coil 32.6 ± 8.4%; P <0.05) in aneurysms coiled with 14 inch coil than those coiled with 10 inch coil. Fourteen inch coil has a higher initial occlusion grade, and lower recurrence rate than 10 coil, but these differences were not significant.</p><p><b>Conclusion:</b> The use of 14 inch framing coil to embolize middle-sized or small cerebral aneurysms is more effective in terms of a higher packing ratio.</p>

    DOI: 10.5797/jnet.oa.2016-0045

    CiNii Books

    Other Link: http://search.jamas.or.jp/link/ui/2017210157

  68. Overlap stenting for in-stent restenosis after carotid artery stenting

    Nishihori M., Ohshima T., Yamamoto T., Goto S., Nishizawa T., Shimato S., Izumi T., Kato K.

    Nagoya Journal of Medical Science   Vol. 78 ( 2 ) page: 143 - 149   2016

     More details

    Publisher:Nagoya Journal of Medical Science  

    Our aim was to assess the clinical safety and efficacy of overlap stenting for in-stent restenosis after carotid artery stenting. The study was conducted between July 2008 and February 2015. A database of consecutive carotid artery stenting procedures was retrospectively assessed to identify the cases of in-stent restenosis that were treated with overlap stenting under proximal or distal protection. The clinical and radiological records of the patients were then reviewed. Of the 155 CAS procedures in 149 patients from the database, 6 patients met the inclusion criteria. All the 6 patients were initially treated with moderate dilatation because of the presence of an unstable plaque. The technical success rate of the overlap stenting was 100%, with no 30-day mortality or morbidity. In addition, there was no further in-stent restenosis during a follow-up period of over 12 months. These results indicated that overlap stenting for in-stent restenosis after carotid artery stenting was both safe and effective in our cohort.

    Scopus

  69. Multimodal Assessment for Balloon Test Occlusion of the Internal Carotid Artery

    Matsubara Noriaki, Izumi Takashi, Okamoto Sho, Araki Yoshio, Shintai Kazunori, Tajima Hayato, Imai Tasuku, Ito Masashi, Nishihori Masahiro, Miyachi Shigeru, Wakabayashi Toshihiko

    Journal of Neuroendovascular Therapy   Vol. 10 ( 3 ) page: 108 - 115   2016

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <b>Objective:</b> Permanent therapeutic occlusion of the carotid artery is one of the treatment options for patients with a large/giant internal carotid artery aneurysm or tumor involving the neck or skull base. Balloon test occlusion (BTO) is performed to predict the tolerance of parent artery occlusion (PAO). The authors combined various modalities to improve the sensitivity of BTO. The purpose of this study is to present the efficacy of the multimodal BTO.<b>Methods:</b> Between January 2008 and September 2014, a total of 50 patients (internal carotid aneurysms: 39, neck or skull base tumor: 8, others: 3; mean 58.4 years, range 7–81 years; 10 men and 40 women) underwent multimodal BTO. Tolerance of PAO was evaluated by the algorithm with various assessment modalities including neurological symptoms with/without induced hypotension, findings of angiogram (collateral flow, venous phase laterality), perfusion CT, and stump pressure. Clinical data of patients with BTO were analyzed retrospectively. Procedures were performed in the angio/CT combination suite. BTO was performed in the usual fashion and when the patient passed the immediate test occlusion, perfusion CT was performed. Subsequently, the angiogram under balloon inflation followed. If the patient did not show neurological symptoms for 20 min, hypotension was induced by intravenous injection of the vasodilator. Neurological symptoms were then checked for more than 30 min.<b>Results:</b> By multimodal assessment of BTO, 33 patients were considered tolerable, six were partially tolerable, and 11 were intolerable. Thirteen of 33 patients with predictive tolerance underwent PAO without bypass, and all but one showed no hemodynamic ischemia postoperatively. Three of six patients with predictive partial tolerance were treated by PAO with extracranial-intracranial bypass, and they experienced no hemodynamic ischemia. In contrast, one with predictive partial tolerance treated by PAO without bypass developed ischemic events as feared.<b>Conclusions:</b> The multimodal BTO is helpful to evaluate the tolerance of PAO and is a reliable predictor of postoperative ischemic events. It reduces risks and increases treatment safety for permanent therapeutic occlusion of the carotid artery.

    DOI: 10.5797/jnet.oa.2015-0012

    CiNii Research

  70. Comparison of Clinical Outcomes Using 10 Coil Versus 14 Coil in Endovascular Coil Embolization for Small and Medium-sized Intracranial Aneurysms: Efficacy of 14 Coil

    Imai Tasuku, Ohshima Tomotaka, Goto Shunsaku, Yamamoto Taiki, Shimato Shinji, Nishizawa Toshihisa, Kato Kyozo, Nishihori Masahiro, Izumi Takashi, Wakabayashi Toshihiko

    Journal of Neuroendovascular Therapy   Vol. 10 ( 4 ) page: 196 - 200   2016

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective:</b> The purpose of this retrospective study was to compare the therapeutic results of middle-sized or small cerebral aneurysms coiling using 10 coil (thickness, 0.0095 inch–0.012 inch) and 14 coil (thickness, 0.0135 inch) as a complex framing coil.</p><p><b>Methods:</b> Fifty aneurysms (maximum size, 4 mm–10 mm) in 50 patients treated in our hospital between May 2012 and May 2015 were assigned in this study. We compared the volume embolization rate, recurrence rate, initial occlusion grade between 14 coil (25 aneurysms) and 10 coil (25 aneurysms).</p><p><b>Results:</b> The mean volume embolization ratio was significantly higher (14 coil 37.5 ± 8.8%, 10 coil 32.6 ± 8.4%; P <0.05) in aneurysms coiled with 14 inch coil than those coiled with 10 inch coil. Fourteen inch coil has a higher initial occlusion grade, and lower recurrence rate than 10 coil, but these differences were not significant.</p><p><b>Conclusion:</b> The use of 14 inch framing coil to embolize middle-sized or small cerebral aneurysms is more effective in terms of a higher packing ratio.</p>

    DOI: 10.5797/jnet.oa.2016-0045

    CiNii Research

  71. Can a Self-expanding Stent Deployed Artery be Safely Clipped Temporarily?

    NISHIHORI Masahiro, OHSHIMA Tomotaka, YAMAMOTO Taiki, GOTO Shunsaku, SHIMATO Shinji, NISHIZAWA Toshihisa, KATO Kyozo

    No Kekkannai Chiryo   Vol. 1 ( 1 ) page: 1 - 7   2016

     More details

    Language:Japanese   Publisher:The Japanese Society for Neuroendovascular Therapy  

    <p><b>Objective</b>: With recent increase of endovascular treatment, direct surgery on vessels with previously placed stents may be encountered. Our question is whether we can shut off the stent-placed vessel safely and reliably with a titanium clip. The authors conducted an experiment in vitro.</p><p><b>Methods</b>: Three types of intracranial stents that have been used in Japan [Enterprise VRD (Codman), Neuroform (Stryker), Wingspan (Stryker)] were deployed to the 3.5-mm diameter silicon tube for vascular anastomosis training. The stent-placed region was blocked with a single temporary clip, one permanent clip, and two permanent clips, respectively. In order to apply pressure linearly, we used a pressurized fluid with 33% glycerol, which was similar to blood in viscosity. While increasing the pressure, the fluid leakage was confirmed. Finally, the stent strut damage around the clipped part was assessed by a cone-beam computed tomography (CT).</p><p><b>Results</b>: It is easier to shut off the flow through Enterprise VRD than Neuroform or Wingspan. Tube with Wingspan is the most difficult to block due to its larger radial force. When we used the two permanent clips, it was possible to block each vessel to a relatively higher pressure up to 180 mmHg. After release, the shape of every stent was promptly restored without stent strut damage.</p><p><b>Conclusion</b>: By using clips it was possible to shut off the blood flow with all three stents temporarily. If neurosurgeons attempt to block the stent-placed parent vessel permanently, they should use two permanent clips.</p>

    DOI: 10.20626/nkc.oa.2015-0047

    CiNii Research

▼display all

Books 1

  1. Use of embolization for the treatment of dural arteriovenous fistula

    Izumi T., Nishihori M., Tsukada T., Araki Y., Uda K., Yokoyama K.

    Arteriovenous Malformations of the Brain  2020.5  ( ISBN:9781536178920

     More details

    Dural arteriovenous fistula (DAVF) is a relatively rare disease, and often develops pulsatile tinnitus. When accompanied by cerebral cortical venous reflux, patients may present with local neurological symptoms. Recently, transarterial embolization using Onyx is often the first-choice treatment for the patients with DAVF. Transvenous embolization for the affected sinus using platinum coils or liquid embolic material, is applied for cavernous sinus DAVF or transverse sinus/sigmoid sinus dural arteriovenous fistula (Borden type II). Since anatomical knowledge required for embolization is not required in the general practice of treating endovascular diseases, physicians treating dAVF must learn the anatomy of the arteries and veins of the head to increase the safety of embolization.

    Scopus

MISC 10

  1. Rare Dilated Collateral Circulation from Accessory Meningeal Artery to Inferolateral Trunk: A Case Report

    IKEZAWA Mizuka, MAEDA Kenko, TAKASU Syuntaro, TAKEMOTO Masaya, NISHIHORI Masahiro, CHOO Jungsu, SAGO Fumihiro, SOMIYA Daiki, DOBA Kohei, IKEDA Akira

    NMC Case Report Journal   Vol. 10 ( 0 ) page: 47 - 50   2023

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>The accessory meningeal artery (AMA) demonstrates various potential anastomoses with the external (ECA) and internal (ICA) carotid arteries. However, rarely does the AMA markedly dilate and compensate for ICA blood flow. A 52-year-old woman with nonspecific symptoms was diagnosed with multiple cerebral aneurysms and abnormal blood vessels observed on magnetic resonance angiography. Digital subtraction angiography revealed four aneurysms and anastomoses between the left AMA and inferolateral trunk (ILT). In addition, two sequential severe flexions were observed in the cervical portion of the left ICA. No ischemic lesions were detected on magnetic resonance imaging. In conclusion, we experienced a rare case in which the AMA-ILT anastomosis was highly developed. This case also presented with the unusual characteristics of an anomaly in the extracranial ICA and multiple aneurysms.</p>

    DOI: 10.2176/jns-nmc.2022-0308

    PubMed

    CiNii Research

  2. Dural Arteriovenous Fistula Mimicking a Brain Tumor on Methionine-positron Emission Tomography: A Case Report

    HANYU Taketo, NISHIHORI Masahiro, IZUMI Takashi, MOTOMURA Kazuya, OHKA Fumiharu, GOTO Shunsaku, ARAKI Yoshio, YOKOYAMA Kinya, UDA Kenji, SAITO Ryuta

    NMC Case Report Journal   Vol. 9 ( 0 ) page: 289 - 294   2022

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>In this article, we report a case wherein a brain tumor was suspected based on computed tomography and magnetic resonance imaging findings. We made an initial diagnosis of malignant brain tumor based on methionine-positron emission tomography (PET) findings, but the correct diagnosis was dural arteriovenous fistula (DAVF). The patient was a 45-year-old man with DAVF who developed headache. Methionine-PET imaging showed high methionine uptake in the lesion. Although the tumor was strongly suspected from the findings of methionine-PET, the diagnosis of DAVF could be made correctly only by interpreting digital subtraction angiography and computed tomographic angiography. The findings of methionine-PET, which is considered useful in the diagnosis and denial of brain tumors, made the diagnosis of DAVF more difficult. The increased uptake of methionine-PET in DAVF is an important finding because, to our knowledge, this study is the first to report such finding. The results of this study might be useful for differential diagnoses when the diagnosis is uncertain.</p>

    DOI: 10.2176/jns-nmc.2022-0055

    PubMed

    CiNii Research

  3. Anterior Communicating Artery Aneurysm with a Peculiar Angiographic Appearance: A Case Study

    OTAWA Masato, IZUMI Takashi, NISHIHORI Masahiro, TSUKADA Tetsuya, OSHIMA Ryosuke, KAWAGUCHI Tomomi, GOTO Shunsaku, IKEZAWA Mizuka, KROPP Asuka Elisabeth, WAKABAYASHI Toshihiko

    NMC Case Report Journal   Vol. 8 ( 1 ) page: 57 - 61   2021.4

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>We describe a case of pulsatile anterior communicating artery aneurysm (A-com AN) with a peculiar angiographic appearance. An 81-year-old man was referred to the department of neurosurgery for a large A-com AN artery aneurysm, which was detected incidentally. The patient hoped not to be treated but to be followed up. After 4 months, magnetic resonance imaging (MRI) revealed the presence of a cerebral edema and hematoma around the aneurysm, and partial thrombus in the upper wall of the aneurysm was suspected. Based on these findings, the patient underwent an immediate coil embolization a day after admission. However, the portion of the neck remnant increased in size after the first procedure. Therefore, 8 months after the initial procedure, he was treated with stent coil embolization. Contrary to the first procedure, angiographic evaluation revealed an active pulsating aneurysm. Moreover, MRI revealed the presence of a partial thrombus in the upper neck segment of the aneurysm, with an intensity that changed over time. The patient underwent cautious treatment and was discharged without any symptoms. This is the first case study to reveal an A-com AN with active pulsation and the relationship between the pulsatile portion of the aneurysm and thrombosed portion by MRI.</p>

    DOI: 10.2176/nmccrj.cr.2020-0036

    PubMed

    CiNii Research

  4. Management of Asymptomatic Vertebral Artery Injury Caused by a Cervical Pedicle Screw Malposition: Two Case Reports

    OTSUKA Takafumi, IZUMI Takashi, NISHIHORI Masahiro, TSUKADA Tetsuya, ARAKI Yoshio, YOKOYAMA Kinya, UDA Kenji, GOTO Shunsaku, IKEZAWA Mizuka, KATO Naoki, NAKANO Mizuki, SAITO Ryuta

    NMC Case Report Journal   Vol. 8 ( 1 ) page: 713 - 717   2021

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>Iatrogenic vertebral artery (VA) injury in cervical fusion is an extremely rare complication but can lead to serious sequelae. We present two successful cases of internal trapping for preventing delayed-onset ischemic stroke after iatrogenic VA stenosis caused by a cervical pedicle screw. A 34-year-old female underwent posterior cervical fusion for C4/C5 dislocation fracture. No neurological deficits were observed after the operation. However, the postoperative images revealed that the left C5 pedicle screw perforated the transverse foramen, and the left VA was suspected to be occluded at the screw insertion site. Before revision surgery, we tried to embolize the injured VA with coils. A microcatheter could be navigated from the ipsilateral VA to the distal of the screw, and internal trapping was performed with coils. Another case is that of a 50-year-old male with cervical spondylosis, who underwent posterior decompression and cervical fusion. The neurological symptoms did not deteriorate after the operation. However, the postoperative computed tomography images revealed the perforation of the right C3 transverse foramen by the pedicle screw. In right vertebral angiography, about 70% stenosis was observed at the screw insertion site. Although revision surgery was not planned due to good stability, we embolized the right VA after balloon occlusion test, to prevent the delayed-onset thromboembolic complications. Both the patients recovered without any neurological deficits. Iatrogenic VA injuries, even if asymptomatic immediately after surgery, can lead to serious sequelae in case of delayed-onset ischemic stroke. Therefore, careful attention should be paid when the screw perforates the transverse foramen.</p>

    DOI: 10.2176/nmccrj.cr.2021-0062

    PubMed

    CiNii Research

  5. Levodopa-responsive Parkinsonism Caused by Recurrence of Large Basilar-tip Aneurysm after Stent-assisted Coil Embolization: A Case Report

    NISHIHORI Masahiro, IZUMI Takashi, TSUKADA Tetsuya, ARAKI Yoshio, YOKOYAMA Kinya, UDA Kenji, WAKABAYASHI Toshihiko

    NMC Case Report Journal   Vol. 8 ( 1 ) page: 107 - 111   2021

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>Aneurysms of the large basilar artery (BA) occasionally cause cranial nerve palsy and motor disorder through mass effect. Since 1967, five cases of cerebral aneurysm leading to parkinsonism have been reported. Herein, we describe a rare case of progressive parkinsonism caused by the recurrence of a large aneurysm of the basilar tip after stent-assisted coil embolization. A 66-year-old man visited our hospital with an asymptomatic large aneurysm (maximum diameter, 21 mm) of the BA tip. Magnetic resonance imaging (MRI) revealed no perianeurysmal edema. Coil embolization with a Y-configuration stent with cross-placement was performed. Although thrombus formation occurred and the perforator infarction was complicated, complete occlusion was achieved. Three months later, the patient developed progressive and severe parkinsonism. MRI revealed mild enlargement of the aneurysm and perianeurysmal mesencephalic edema with minor neck recurrence. A trial administration of levodopa and additional stent-assisted coil embolization were performed. Levodopa dramatically improved parkinsonism; thus, the patient’s symptoms were controlled by a continuous levodopa regimen. In a large BA-tip aneurysm patient, moderate regrowth and minor neck recurrence occurred after initial treatment, and chronic compression of the midbrain caused secondary parkinsonism. In such cases, it is important to consider levodopa administration and therapeutic strategies to prevent recurrence or regrowth.</p>

    DOI: 10.2176/nmccrj.cr.2020-0023

    PubMed

    CiNii Research

  6. Coexistence of a Dural Arteriovenous Fistula and Pial Arteriovenous Malformation Sharing a Common Drainer

    UDA Kenji, IZUMI Takashi, KANAMORI Fumiaki, YOKOYAMA Kinya, TSUKADA Tetsuya, NISHIHORI Masahiro, SHINTAI Kazunori, OKAMOTO Sho, ARAKI Yoshio

    NMC Case Report Journal   Vol. 8 ( 1 ) page: 557 - 563   2021

     More details

    Language:English   Publisher:The Japan Neurosurgical Society  

    <p>In cases of a dural arteriovenous fistula (AVF) with a pial arterial supply, postoperative hemorrhagic complications occur frequently. Six cases in which patients were diagnosed with a coexisting dural AVF and pial arteriovenous malformation (AVM) sharing a common drainer are presented. These cases were initially thought to be dural AVFs with pial arterial supplies, but careful examination of preoperative images showed that a pial AVM coexisted near the dural AVF, and that both shared a common drainer. The coexistence of a pial AVM is difficult to notice during surgery; for this reason, determining the presence of a pial AVM on preoperative imaging is essential to safely treat a dural AVF with a pial arterial supply. The details of each case, specifically, the diagnostic evidence for this condition (coexisting dural AVF and pial AVM sharing a common drainer), as well as imaging findings that should be noted, are presented.</p>

    DOI: 10.2176/nmccrj.cr.2020-0349

    PubMed

    CiNii Research

  7. Cortical-Sulcal Hyperintensity in Fluid-attenuated Inversion Recovery Images and Postoperative Transient Neurological Events after Indirect Revascularization Surgery for Moyamoya Disease

    荒木芳生, 岡本奨, 横山欣也, 太田慎次, 宇田憲司, 村岡真輔, 金森史哲, 西堀正洋, 泉孝嗣, 若林俊彦

    脳卒中の外科   Vol. 46 ( 6 ) page: 439 - 444   2018.11

     More details

    Language:Japanese  

    J-GLOBAL

  8. 非もやもや病小児閉塞性脳血管障害の診断と治療

    荒木芳生, 近藤五郎, 栗本路弘, 芝良樹, 宇田憲司, 太田慎次, 村岡真輔, 金森史哲, 泉孝嗣, 西堀正洋, 岡本奨, 若林俊彦

    Mt. Fuji Workshop on CVD   Vol. 36   page: 39 - 45   2018.7

     More details

    Language:Japanese  

    J-GLOBAL

  9. 小児・若年「非もやもや」頭蓋内血管狭窄の治療と予後 非もやもや病小児閉塞性脳血管障害の診断と治療

    荒木 芳生, 近藤 五郎, 栗本 路弘, 芝 良樹, 宇田 憲司, 太田 慎次, 村岡 真輔, 金森 史哲, 泉 孝嗣, 西堀 正洋, 岡本 奨, 若林 俊彦

    The Mt. Fuji Workshop on CVD   Vol. 36   page: 39 - 45   2018.7

     More details

    Language:Japanese   Publisher:(株)にゅーろん社  

    当院で非もやもや病小児閉塞性脳血管障害が疑われた5例(男児2例、女児3例、平均年齢11.4歳)を対象に臨床経過や画像所見、神経学的予後について検討した。その結果、5例とも生来健康で外傷歴や血管危険因子は認めなかった。画像所見では、全例で内頸動脈終末部の狭窄を認めたが、ウイリス動脈輪周囲や基底核にもやもや血管は伴っていなかった。だが、3例(60%)は基底核を中心とする脳梗塞で発症していた。また、脳動脈解離に特徴的な所見を呈する症例はなく、1年以内の水痘ウイルス感染、自己免疫疾患や膠原病、全身性血管病変なども否定的であった。RNF213遺伝子多型は1例のみ陽性であった。脳梗塞を認めた3例では発症後早期にMRA上の狭窄進行がみられたが、それ以外は発症後から改善傾向にあった。最終診察時におけるmodified Rankin Scaleは全例で1以下であった。

  10. The Treatment Outcome of Transarterial Embolization for Isolated Sinus Type Dural Arteriovenous Fistula between NBCA and Onyx

    JNET : journal of neuroendovascular therapy : official journal of the Japanese Society for Neuroendovascular Therapy   Vol. 11 ( 6 ) page: 279 - 287   2017.6

     More details

    Language:English   Publisher:The Japanese Society for Neuroendovascular Therapy  

    CiNii Books

▼display all

Presentations 7

  1. コイル塞栓術の治療戦略とコイル選択

    西堀正洋、泉孝嗣、塚田哲也

    第36回日本脳神経血管内治療学会学術総会  2020.11.19 

     More details

    Event date: 2020.11

    Language:Japanese   Presentation type:Public lecture, seminar, tutorial, course, or other speech  

    Venue:京都   Country:Japan  

  2. フローダイバーターステントの術後長期経過における動脈瘤収縮に関連する因子の解析  

    西堀正洋、泉孝嗣、塚田哲也、池澤瑞香、後藤峻作、大塚崇史、加藤直毅、中野瑞生、クロップ明日香、若林俊彦

    第36回日本脳神経血管内治療学会学術総会  2020.11.19 

     More details

    Event date: 2020.11

    Language:Japanese   Presentation type:Symposium, workshop panel (public)  

    Venue:京都   Country:Japan  

  3. 不安定プラークはCASハイリスクか? Invited

    西堀正洋、泉孝嗣、塚田哲也、池澤瑞香、後藤峻作、大塚崇史、加藤直毅、中野瑞生、クロップ明日香、若林俊彦

    第36回日本脳神経血管内治療学会学術総会  2020.11.19 

     More details

    Event date: 2020.11

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:京都  

  4. 頸動脈ステント留置術 (CAS) feel the difference Invited

    西堀正洋、泉孝嗣、塚田哲也

    第36回日本脳神経血管内治療学会学術総会  2020.11.19 

     More details

    Event date: 2020.11

    Language:Japanese   Presentation type:Public lecture, seminar, tutorial, course, or other speech  

    Venue:京都   Country:Japan  

  5. フローダイバーターステントの術後長期経過における動脈瘤収縮に関連する因子の解析  

    西堀正洋、泉孝嗣、塚田哲也、池澤瑞香、後藤峻作、大塚崇史、加藤直毅、中野瑞生、クロップ明日香、若林俊彦

    第79回日本脳神経外科学会総会  2020.10.15 

     More details

    Event date: 2020.10

    Language:Japanese   Presentation type:Symposium, workshop panel (public)  

    Venue:第79回日本脳神経外科学会総会   Country:Japan  

  6. 不安定プラークはCASハイリスクか?

    西堀正洋、泉孝嗣、塚田哲也、池澤瑞香、後藤峻作、大塚崇史、加藤直毅、中野瑞生、クロップ明日香、若林俊彦

    第45回日本脳卒中学会学術集会  2020.8.23 

     More details

    Event date: 2020.8

    Language:Japanese   Presentation type:Oral presentation (general)  

    Venue:横浜   Country:Japan  

  7. 破裂大型内頚動脈瘤に対して段階的血管内治療を行った3例

    西堀正洋、泉孝嗣、塚田哲也、池澤瑞香、後藤峻作、大塚崇史、加藤直毅、中野瑞生、クロップ明日香、若林俊彦

    第45回日本脳卒中学会学術集会   2020.8.23 

     More details

    Event date: 2020.8

    Language:Japanese   Presentation type:Poster presentation  

    Venue:横浜   Country:Japan  

▼display all

KAKENHI (Grants-in-Aid for Scientific Research) 1

  1. Sexual hormone concentration measurement in intracranial dural arteriovenous fistulas

    Grant number:18K16580  2018.4 - 2022.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Early-Career Scientists

    Nishihori Masahiro

      More details

    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\1950000 ( Direct Cost: \1500000 、 Indirect Cost:\450000 )

    Dural arteriovenous fistula is a rare intracranial shunt disease that occurs at various intracranial sites, with differences between men and women at each location. The cavernous sinus (CS) is more than twice as likely to be involved in women than in men. Although trauma, inflammation, and other factors are contributing factors, the cavernous sinus is in contact with the pituitary gland. It is thought to be affected by sex hormones. Blood samples were collected from 25 patients, and sex hormone levels were measured at each site. There were significant differences in E2 and LH between the internal jugular vein and peripheral areas. E2 was also significantly different between the CS and transverse sinus (TS) groups. The internal jugular vein area was significantly higher than the peripheral blood in the CS group. For LH, there was an overall significant increase in blood drawn in the internal jugular vein compared to peripheral in women.

 

Teaching Experience (On-campus) 3

  1. 血管吻合実習

    2020

     詳細を見る

    クリニカルシュミレーションセンターにて血管吻合実習を行なう

  2. 脳新規外科 脳血管内治療・画像講義

    2020

     詳細を見る

    血管撮影室において、脳血管内治療・脳卒中画像の講義を行なう

  3. PBLチュートリアル

    2020

     詳細を見る

    症例ベースでの問題解決型チュートリアル授業

 

Academic Activities 1

  1. The 46th congress of japanese stroke society

    Role(s):Peer review

    2021.3

     More details

    Type:Academic society, research group, etc.