Faculty Profiles - SAITO Ryuta

Papers - SAITO Ryuta

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

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

特集癒着性くも膜炎の病態と治療法を学ぼう術後に生じる癒着性くも膜炎

西村由介, 永島吉孝, 齋藤竜太

脊椎脊髄ジャーナル Vol. 35 ( 2 ) page： 99 - 105 2022.6

Direct intracranial invasion of eccrine spiradenocarcinoma of the scalp: a case report and literature review. International journal Open Access

Yuji Kibe, Kuniaki Tanahashi, Kazuhiro Ohtakara, Yuka Okumura, Fumiharu Ohka, Kazuhito Takeuchi, Yuichi Nagata, Kazuya Motomura, Sho Akahori, Akihiro Mizuno, Hiroo Sasaki, Hiroyuki Shimizu, Junya Yamaguchi, Tomohide Nishikawa, Kenji Yokota, Ryuta Saito

BMC neurology Vol. 22 ( 1 ) page： 223 - 223 2022.6

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

BACKGROUND: Eccrine spiradenocarcinoma (SC), also known as malignant eccrine spiradenoma, is a rare malignant cutaneous adnexal neoplasm arising from long-standing benign eccrine spiradenoma. Malignant skin tumors rarely show direct intracranial invasion. However, once the intracranial structure is infiltrated, curative excision with sufficient margins can become extremely difficult, particularly when the venous sinuses are involved. No effective adjuvant therapies have yet been established. Here, we report an extremely rare case of scalp eccrine SC with direct intracranial invasion, which does not appear to have been reported previously. CASE PRESENTATION: An 81-year-old woman presented with a large swelling on the parietal scalp 12 years after resection of spiradenoma from the same site. The tumor showed intracranial invasion with involvement of the superior sagittal sinus and repeated recurrences after four surgeries with preservation of the sinus. The histopathological diagnosis was eccrine SC. Adjuvant high-precision external beam radiotherapy (EBRT) proved effective after the third surgery, achieving remission of the residual tumor. The patient died 7 years after the first surgery for SC. CONCLUSIONS: Scalp SC with direct intracranial invasion is extremely rare. Radical resection with tumor-free margins is the mainstay of treatment, but the involvement of venous sinuses makes this unfeasible. High-precision EBRT in combination with maximal resection preserving the venous sinuses could be a treatment option for local tumor control.

DOI： 10.1186/s12883-022-02749-4

Phase II single-arm, multi-center, physician-initiated clinical trial of convection-enhanced delivery of nimustine hydrochloride (ACNU) against diffuse intrinsic pontine gliomas

Ryuta Saito, Masayuki Kanamori, Yohei Mineharu, Yoshiki Arakawa, Kentaro Chiba, Yasuo Aihara, Ichiyo Shibahara, Toshihiro Kumabe, Kenichiro Matsuda, Yukihiko Sonoda, Fumiaki Takahashi, Teiji Tominaga

JOURNAL OF CLINICAL ONCOLOGY Vol. 40 ( 16 ) 2022.6

Quick and simple dural threading technique for transsphenoidal surgery - dural tenting, haemostasis and skull base reconstruction. International journal

Kazuhito Takeuchi, Yuichi Nagata, Kuniaki Tanahashi, Ryuta Saito

Acta neurochirurgica Vol. 164 ( 6 ) page： 1619 - 1622 2022.6

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

BACKGROUND: Dural suturing is one of the most robust reconstruction methods in transsphenoidal surgery; however, the technique is considered difficult, primarily due to the restricted range of needle movement. METHOD: We performed dural threading during transsphenoidal surgery by holding the needle with forceps as a hook and moving the needle in a distal to proximal direction. CONCLUSION: Our dural suturing technique is simple and quick. It can be used not only for dural closure but also for other procedures, such as controlling haemostasis from the intercavernous sinus and dural tenting.

DOI： 10.1007/s00701-022-05227-5

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

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

Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences Vol. 28 ( 3 ) page： 323 - 331 2022.6

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

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

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

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

Recent Molecular and Genetic Findings in Intramedullary Spinal Cord Tumors. International journal Open Access

Yoshitaka Nagashima, Yusuke Nishimura, Kaoru Eguchi, Junya Yamaguchi, Shoichi Haimoto, Fumiharu Ohka, Masakazu Takayasu, Ryuta Saito

Neurospine Vol. 19 ( 2 ) page： 262 - 271 2022.6

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

The study of genetic alterations and molecular biology in central nervous system (CNS) tumors has improved the accuracy of estimations of patient prognosis and tumor categorization. Therefore, the updated 2021 World Health Organization (WHO) classification includes various diagnostic genes, molecules, and pathways for diagnosis, as well as histological findings. These findings are expected both to have diagnostic applications and to facilitate new targeted therapies that target tumor-specific genetic changes and molecular biology. Intramedullary spinal cord tumors (IMSCTs) are rare CNS tumors that are difficult to treat because they occur in eloquent areas. Although the genetic underpinnings of IMSCTs remain unclear compared to their intracranial counterparts, the genetic characteristics of these tumors are gradually being revealed. Here, we describe the major changes in the new 2021 WHO classification and review the major types of IMSCTs, with an emphasis on their clinical features and genetic alterations.

DOI： 10.14245/ns.2244168.084

多発脳腫瘍にて中枢神経原発悪性リンパ腫と診断し得た脊髄病変の一例

鬼頭大志, 平野聡子, 原一洋, 大岡史治, 永田雄一, 齋藤竜太, 勝野雅央

臨床神経学 Vol. 62 ( 6 ) page： 508 - 508 2022.6

Supratotal Resection of Gliomas With Awake Brain Mapping: Maximal Tumor Resection Preserving Motor, Language, and Neurocognitive Functions. International journal Open Access

Kazuya Motomura, Fumiharu Ohka, Kosuke Aoki, Ryuta Saito

Frontiers in neurology Vol. 13 page： 874826 - 874826 2022.5

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

Gliomas are a category of infiltrating glial neoplasms that are often located within or near the eloquent areas involved in motor, language, and neurocognitive functions. Surgical resection being the first-line treatment for gliomas, plays a crucial role in patient outcome. The role of the extent of resection (EOR) was evaluated, and we reported significant correlations between a higher EOR and better clinical prognosis of gliomas. However, recurrence is inevitable, even after aggressive tumor removal. Thus, efforts have been made to achieve extended tumor resection beyond contrast-enhanced mass lesions in magnetic resonance imaging (MRI)-defined areas, a process known as supratotal resection. Since it has been reported that tumor cells invade beyond regions visible as abnormal areas on MRI, imaging underestimates the true spatial extent of tumors. Furthermore, tumor cells have the potential to spread 10-20 mm away from the MRI-verified tumor boundary. The primary goal of supratotal resection is to maximize EOR and prolong the progression-free and overall survival of patients with gliomas. The available data, as well as our own work, clearly show that supratotal resection of gliomas is a feasible technique that has improved with the aid of awake functional mapping using intraoperative direct electrical stimulation. Awake brain mapping has enabled neurosurgeons achieve supratotal resection with favorable motor, language, and neurocognitive outcomes, ensuring a better quality of life in patients with gliomas.

DOI： 10.3389/fneur.2022.874826

Symptomatic hyperperfusion after combined revascularization surgery in patients with pediatric moyamoya disease: patient series Open Access

Araki, Y, Mamiya, T, Fujita, N, Yokoyama, K, Uda, K, Kanamori, F, Takayanagi, K, Ishii, K, Nishihori, M, Takeuchi, K, Tanahashi, K, Nagata, Y, Nishimura, Y, Tanei, T, Muraoka, S, Izumi, T, Kato, K, Saito, R

Journal of Neurosurgery: Case Lessons Vol. 3 ( 19 ) 2022.5

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

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

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

脳腫瘍研究のcutting edge-先端画像、実験/分子病理、デジタル病理- 神経膠腫の術中迅速遺伝子変異解析を目指した高速リアルタイムPCR法の確立

前田紗知, 大岡史治, 北野詳太郎, 本村和也, 青木恒介, 西川知秀, 山口純矢, 木部祐士, 齋藤竜太

Brain Tumor Pathology Vol. 39 ( Suppl. ) page： 069 - 069 2022.5