Faculty Profiles - SAITO Ryuta

Imaging features of localized IDH wild-type histologically diffuse astrocytomas: a single-institution case series. Reviewed International journal Open Access

Yuji Kibe, Kazuya Motomura, Fumiharu Ohka, Kosuke Aoki, Hiroyuki Shimizu, Junya Yamaguchi, Tomohide Nishikawa, Ryuta Saito

Scientific reports Vol. 13 ( 1 ) page： 23 - 23 2023.1

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

Isocitrate dehydrogenase wild-type (IDHwt) diffuse astrocytomas feature highly infiltrative patterns, such as a gliomatosis cerebri growth pattern with widespread involvement. Among these tumors, localized IDHwt histologically diffuse astrocytomas are rarer than the infiltrative type. The aim of this study was to assess and describe the clinical, radiographic, histopathological, and molecular characteristics of this rare type of IDHwt histologically diffuse astrocytomas and thereby provide more information on how its features affect clinical prognoses and outcomes. We retrospectively analyzed the records of five patients with localized IDHwt histologically diffuse astrocytomas between July 2017 and January 2020. All patients were female, and their mean age at the time of the initial treatment was 55.0 years. All patients had focal disease that did not include gliomatosis cerebri or multifocal disease. All patients received a histopathological diagnosis of diffuse astrocytomas at the time of the initial treatment. For recurrent tumors, second surgeries were performed at a mean of 12.4 months after the initial surgery. A histopathological diagnosis of glioblastoma was made in four patients and one of gliosarcoma in one patient. The initial status of IDH1, IDH2, H3F3A, HIST1H3B, and BRAF was "wild-type" in all patients. TERT promoter mutations (C250T or C228T) were detected in four patients. No tumors harbored a 1p/19q codeletion, EGFR amplification, or chromosome 7 gain/10 loss (+ 7/ - 10). We assessed clinical cases of localized IDHwt histologically diffuse astrocytomas that resulted in malignant recurrence and a poor clinical prognosis similar to that of glioblastomas. Our case series suggests that even in patients with histologically diffuse astrocytomas and those who present with radiographic imaging findings suggestive of a localized tumor mass, physicians should consider the possibility of IDHwt histologically diffuse astrocytomas.

DOI： 10.1038/s41598-022-25928-2

Concurrent cerebral infarction and intracranial tuberculoma induced by the carotid plaque complicated with miliary tuberculosis. Reviewed International journal

Shinsuke Muraoka, Takuya Oguri, Risa Kimura, Keita Sakurai, Yasuhiko Suzuki, Hiroyuki Shimizu, Satoshi Shinoda, Naoki Koketsu, Yoshio Araki, Ryuta Saito

Acta neurochirurgica Vol. 165 ( 3 ) page： 647 - 650 2023.1

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

Cerebrovascular complications of central nervous system tuberculosis (TB) are predictors of poor prognosis and adverse outcomes. These complications are mainly intracranial arterial involvement, with occasional venous involvement. Here, we present a 67-year-old woman with concurrent cerebral infarction and intracranial tuberculoma induced by the carotid plaque complicated by miliary tuberculosis. Mycobacterium tuberculosis was observed on the luminal side of the carotid plaques in pathological specimens. Treatment with anti-TB drugs alone would likely not cure the patient, as M. tuberculosis would continue to disseminate. Endarterectomy could directly remove the embolic source, and a complete cure was achieved.

DOI： 10.1007/s00701-023-05489-7

Cutoff values for the best management strategy for magnetic resonance-guided focused ultrasound ablation for essential tremor. Reviewed International journal

Jun Torii, Satoshi Maesawa, Daisuke Nakatsubo, Takahiko Tsugawa, Sachiko Kato, Tomotaka Ishizaki, Sou Takai, Masashi Shibata, Toshihiko Wakabayashi, Takashi Tsuboi, Masashi Suzuki, Ryuta Saito

Journal of neurosurgery Vol. 138 ( 1 ) page： 38 - 49 2023.1

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

OBJECTIVE: The efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) ablation for essential tremor (ET) is well known; however, no prognostic factors have been established. The authors aimed to retrospectively investigate MRgFUS ablation outcomes and associated factors and to define the cutoff values for each prognostic factor. METHODS: Sixty-four Japanese patients who underwent unilateral ventral intermediate nucleus thalamotomy with MRgFUS for ET were included. Follow-up evaluations were performed at 1 week and 1, 3, 6, 12, and 24 months postoperatively. Tremor suppression was evaluated using the Clinical Rating Scale for Tremor (CRST), and adverse effects were recorded postoperatively. Outcome-associated factors were examined preoperatively, intraoperatively, and postoperatively using multivariate analyses. The cutoff values for the prognostic factors were calculated using receiver operating characteristics. RESULTS: Percentage improvements in the CRST scores of the affected upper limb were 82.4%, 72.2%, 68.6%, and 65.9% at 1, 3, 6, and 12 months, respectively. Preoperatively, a high skull density ratio (SDR) (p ≤ 0.047), low CRST part B score (used to assess tremors during several tasks) (cutoff value 25, p ≤ 0.041), and nonoccurrence of resting tremors (p = 0.027) were significantly associated with improved tremor control. An intraoperatively high maximum mean temperature (cutoff value 52.5°C, p ≤ 0.047), postoperatively large lesion (cutoff value 3.9 mm in the anterior-posterior direction, p ≤ 0.002; cutoff value 5.0-5.55 mm in the superior-inferior direction, p ≤ 0.026), and small transducer focus correction (p ≤ 0.015) were also associated with improved tremor control. No valid cutoff value was found for SDR. Adverse effects (limb weakness, sensory disturbance, ataxia/walking disturbance, dysgeusia, dysarthria, and facial swelling) occurred transiently and were associated with high SDR, high temperature, high number of sonication sessions, large lesion, and occurrence of resting tremor. Patients who developed leg weakness experienced greater percentage improvement in tremors at 3 months postoperatively than those who did not. CONCLUSIONS: MRgFUS ablation could be used to achieve good tremor control with acceptable adverse effects in Japanese patients with ET. The relatively low SDR in Asian ethnic groups as compared with that of Western populations makes treatment difficult; however, the cutoff values obtained in this study may be useful for achieving good treatment outcomes even in such patients. Clinical trial registration no.: UMIN000026952 (University Hospital Medical Information Network). ABBREVIATIONS: ACPC = anterior commissure-posterior commissure; AP = anterior to posterior; CRST = Clinical Rating Scale for Tremor; ET = essential tremor; MRgFUS = magnetic resonance-guided focused ultrasound; PC = posterior commissure; PSA = posterior subthalamic area; RL = right to left; ROC = receiver operating characteristic; SDR = skull density ratio; SI = superior to inferior; T2WI = T2-weighted imaging; VIM = ventral intermediate nucleus.

DOI： 10.3171/2022.3.JNS212460

[Seizure Semiology and Functional Anatomy in the Cerebral Cortex].

Satoshi Maesawa, Tomotaka Ishizaki, Ryuta Saito

No shinkei geka. Neurological surgery Vol. 51 ( 1 ) page： 17 - 28 2023.1

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

Understanding the semiology and underlying anatomy of each seizure is essential for epilepsy surgeons. According to the International League Against Epilepsy(ILAE)classification in 2017, seizure types are classified as focal, generalized, or unknown onset, all of which are further classified as motor or non-motor onset. Impairment of awareness is involved in consciousness systems(consisting of subcortical structures such as the thalamus and upper brain stem)and cortical structures(including the frontoparietal association cortices). Seizures with motor features are divided into elementary symptoms for which myoclonic, clonic, and tonic expressions reflect the somatotopy of the primary motor cortex; and integrated or gestural motor expression representing activation of the motor association cortex. A rostrocaudal gradient is demonstrated in hyperkinetic movements in frontal lobe epilepsy. Non-motor epileptic features should be understood together with auras, which correspond to focal aware seizures and hold crucial localizing semiologic values. The correlation between functional anatomy and seizure semiology is justified by invasive recordings such as stereotactic electroencephalography and subdural recordings, and also confirmed by seizure outcomes after resection of supposed epileptogenic zones. In addition to the conventional localization theory, it is necessary to consider the neural network theory for further recognition of the functionally anatomical basis in an incomprehensible demonstration of seizures.

DOI： 10.11477/mf.1436204711

Surgical treatment for recurrent pediatric malignant brain tumors

振戦優位型パーキンソン病(TD-PD)におけるMRガイド下集束超音波治療(MRgFUS)の適応判断と治療効果の検討

中坪大輔, 前澤聡, 津川隆彦, 加藤祥子, 鳥居潤, 武藤学, 伊藤芳記, 坪井崇, 鈴木将史, 若林俊彦, 勝野雅央, 齊藤竜太

日本定位・機能神経外科学会プログラム・抄録集 Vol. 62回 page： 133 - 133 2023.1

Sonoda Yukihiko, Matsuda Ken-ichiro, Ito Miiko, Saito Ryuta, Kanamori Masayuki, Kanemura Yonehiro, Tominaga Teiji

Nervous System in Children Vol. 48 ( 1 ) page： 33 - 38 2023

Language：Japanese Publisher：The Japanese Society for Pediatric Neurosurgery

The effect of surgical resection on recurrent pediatric malignant brain tumors is still controversial. We analyzed cases of seven patients who underwent surgical resection of recurrent lesions.In all patients, the Karnofsky performance status was not aggravated after multiple surgeries. The progression free survival periods in four patients with posterior infratentorial ependymomas were 10, 18, 24, and 35 months. Three of the four patients survived about 100 months following multiple repeat surgeries and re-radiation. However, one patient died because of disseminated lesions 21 months after the initial therapy. These results suggested that repeat surgeries for recurrent ependymomas were effective unless disseminated lesions were detected. However, the effects of repeat surgeries were modest in our patients with glioblastoma. Based on the World Health Organization’s Classification of Central Nervous System tumors, 5th Edition, these tumors were diagnosed as diffuse astrocytoma, IDH-mutant, grade 4, and diffuse hemispheric tumor, H3 G34-mutant. Although these tumors did not recur as leptomeningeal dissemination, local tumor control was very poor by repeat surgeries. Finally, one infant case with SHH, TP53-wild type medulloblastoma survived more than 100 months following repeat surgeries and chemotherapy alone. The indication of repeat surgeries for medulloblastoma might be limited; thus, precise molecular and histological information was useful to determine therapy.

DOI： 10.34544/jspn.48.1_33

Speech-language Pathology Rehabilitation in a Case of Jefferson Fracture Complicated with Lower Cranial Nerve Palsies.

Investigation of cystine as differential diagnostic biomarker between astrocytomas and oligodendrogliomas based on global- and targeted analysis using liquid chromatography/tandem mass spectrometric analysis Reviewed

Masahiro Watanabe, Masamitsu Maekawa, Masayuki Kanamori, Minami Yamauchi, Ai Abe, Yoshiteru Shimoda, Ryuta Saito, Hidenori Endo, Nariyasu Mano

Advances in Biomarker Sciences and Technology Vol. 5 page： 76 - 85 2023

Usefulness of Stanch Belt Plus in Postoperative Management after Endovascular Neurosurgery Reviewed International journal

Nishihori Masahiro, Kawase Ryo, Izumi Takashi, Nakase Hiroe, Onishi Erina, Saito Ryuta

Journal of Neuroendovascular Therapy Vol. 17 ( 12 ) page： 281 - 285 2023

Authorship：Last author Language：English Publisher：The Japanese Society for Neuroendovascular Therapy

Objective: We verified the usefulness of patient management using a balloon-pressurized belt (Stanch Belt Plus) to prevent puncture site hematomas, which can occur at a specific rate even with hemostatic devices after endovascular neurosurgery.Methods: A total of 113 patients who underwent endovascular surgery with a femoral puncture from April 2019 to September 2020 were divided into two groups: 31 cases using a traditional compression belt and 82 cases using a newly introduced balloon-pressurized belt during this period. The clinical data were analyzed retrospectively. The chi-square test and Mann–Whitney U test were used to test for significant differences.Results: There were no significant differences in treatment procedures or frequency of hemostatic device use, but the balloon-pressurized belt group had a significantly lower incidence of hematomas (2.4% vs 12.9%, p <0.05) and a significantly lower incidence of moderate or higher lumbago (22.0% vs 41.9%, p <0.05). The incidence of epidermal detachment tended to be low; however, no significant difference was observed (3.7% vs. 12.9%, n.s.).Conclusion: Patient management with the newly introduced balloon-pressurized belt may decrease the occurrence of groin hematoma and lumbago among complications after endovascular neurosurgery.

DOI： 10.5797/jnet.oa.2023-0053

Latest Treatments and Expectations for Precision Medicine against Malignant Glioma Invited Reviewed Open Access

Saito Ryuta

Japanese Journal of Neurosurgery Vol. 32 ( 3 ) page： 148 - 153 2023

Authorship：Lead author,　Last author,　Corresponding author Language：Japanese Publisher：The Japanese Congress of Neurological Surgeons

Malignant glioma is one of the most intractable malignant neoplasms. Standard treatment consists of surgery, radiotherapy, and chemotherapy, although substantial therapeutic effects cannot be expected. In particular, the blood-brain barrier (BBB) protects the central nervous system, reducing the effectiveness of chemotherapy. Temozolomide is the standard treatment, but it only prolongs the median survival time by about two months compared to surgery and radiation. Molecular-targeted therapies, which have revolutionized the treatment of many cancer types, have all failed to treat malignant gliomas, and the focus is now on the spatial and temporal diversity of tumors. In addition, the problem of drug penetration across the BBB has been refocused. Precision medicine is also attracting great expectations, but panel testing can only be done once. Even if an expert panel recommends a treatment, there is a problem in that most treatments have to rely on investigational therapies. It is also known that even if there is a draggable genetic abnormality in tumors, drugs targeting those abnormalities are often ineffective against brain tumors. Therefore, it is necessary that all novel therapeutic approaches, such as virus therapy, neutron capture therapy, and drug delivery techniques like convection-enhanced delivery, be employed to improve treatment outcomes in malignant glioma.

DOI： 10.7887/jcns.32.148

Unique vascular structures of a radicular arteriovenous fistula at the craniocervical junction along the first cervical spinal nerve: A case report. International journal Open Access

Kentaro Wada, Takafumi Tanei, Kenichi Hattori, Hisashi Hatano, Shigeru Fujitani, Risa Ito, Hiroaki Kubo, Yusuke Nishimura, Satoshi Maesawa, Ryuta Saito

Surgical neurology international Vol. 14 page： 85 - 85 2023

Language：English

BACKGROUND: An arteriovenous fistula (AVF) at the craniocervical junction (CCJ) is a rare vascular malformation. Definitive diagnosis and curative treatment of CCJ AVF are challenging. CASE DESCRIPTION: A 77-year-old man presented with subarachnoid hemorrhage. Cerebral angiography showed an AVF at the CCJ, which drained into a radicular vein. The lesion was fed by a vertebral artery, anterior and lateral spinal arteries (LSAs), and the occipital artery (OA). There were two unique structures: the LSA originating from the posterior inferior cerebellar artery of the extracranial V3 segment and the OA feeding the shunt. Curative treatment involved two steps: endovascular embolization of feeders using Onyx and surgical shunt disconnection. Feeding arteries were blackened by Onyx, which helped identify the location of the shunt. The shunt was located behind the first cervical (C1) spinal nerve, and the draining vein was confirmed on the deep side of the nerve. A clip was applied to the draining vein distal to the shunt. Tiny vessels supplying the shunt were then coagulated referring to blackened arteries. CONCLUSION: A radicular AVF at the CCJ along the C1 spinal nerve had unique vascular structures. Definitive diagnosis and curative treatment were achieved by combining endovascular embolization using Onyx and direct surgery.

DOI： 10.25259/SNI_122_2023

Shota Horiike, Yasuhiro Nakajima, Mamoru Matsuo, Akinori Kageyama, Ayako Motomura, Takashi Tsujiuchi, Ryuta Saito

NMC case report journal Vol. 10 ( 0 ) page： 157 - 162 2023

Language：English Publisher：The Japan Neurosurgical Society

A 68-year-old man presented with a Jefferson fracture leading to lower cranial nerve palsies affecting the ninth, tenth, and twelfth cranial nerves with a traumatic basilar impression. On the X day, the patient underwent occipitocervical posterior fixation surgery; the surgery was uneventful. However, just after the surgery, epipharyngeal palsy and airway obstruction occurred. Consequently, tracheostomy was needed. On the X+8 day, speech-language pathology (SLP) therapy was initiated for decannulation. On the X+21 day, the patient could clear all the checkpoints and was decannulated. On the X+36 day, the patient was discharged home and SLP therapy was continued. On the X+171 day, his SLP therapy was halted. However, the patient continued to complain that he could not speak as fast as before, and his quality of life remained compromised. Some studies reported that lower cranial nerve palsies affecting the ninth to the twelfth cranial nerve occur in conjunction with Jefferson fractures. Thus, SLP therapy is crucial for Jefferson fracture cases.

DOI： 10.2176/jns-nmc.2022-0060

Simultaneous Aneurysmal Subarachnoid Hemorrhage and Epistaxis in an Untreated Prolactinoma: A Case Report and Literature Review.

Masahiro Nishihori, Takashi Izumi, Kazuhito Takeuchi, Shunsaku Goto, Fumiaki Kanamori, Kenji Uda, Kinya Yokoyama, Yoshio Araki, Ryuta Saito

NMC case report journal Vol. 10 ( 0 ) page： 163 - 168 2023

Language：English Publisher：The Japan Neurosurgical Society

A 61-year-old man presented with massive epistaxis, amaurosis, nausea, and severe headache. A detailed examination revealed a subarachnoid hemorrhage and prolactinoma. Angiography showed a small internal carotid artery pseudoaneurysm and inadequate collateral circulation; thus, uncomplicated coil embolization was performed. Considering the side effects of medication, such as cerebrospinal fluid rhinorrhea, the patient was followed up for asymptomatic prolactinoma without medication after discharge. At 40 months later, aneurysm recurrence was confirmed. Flow diverter device placement was performed, and the outcomes were excellent. In the present report, we described a rare case of a ruptured internal carotid artery aneurysm in an untreated prolactinoma and discussed the literature.

DOI： 10.2176/jns-nmc.2022-0355

Ruptured Middle Cerebral Artery Aneurysm in an Infant: Case Report and Literature Review.

Sacral arteriovenous fistula with lower thoracic cord edema without perimedullary vein enlargement Open Access

Ishii, M, Nishimura, Y, Nagashima, Y, Tanei, T, Nishihori, M, Izumi, T, Saito, R

Surgical Neurology International Vol. 14 page： 295 2023

Hayato Yokoyama, Masahiro Nishihori, Takashi Izumi, Shunsaku Goto, Michihiro Kurimoto, Mihoko Kato, Fumiaki Kanamori, Kenji Uda, Kinya Yokoyama, Yoshio Araki, Ryuta Saito

NMC case report journal Vol. 10 ( 0 ) page： 177 - 183 2023

Language：English Publisher：The Japan Neurosurgical Society

Intracranial aneurysms (IA) in infants are reportedly rare at 0.5% to 4.5% of all aneurysms. Furthermore, subarachnoid hemorrhage in infants younger than three months are even rarer as it has been reported in approximately 20 cases only till date. A 3-month-old infant with seizures and impaired consciousness was admitted to our hospital. Three-dimensional computed tomography angiography (3D-CTA) revealed a dissecting aneurysm with a maximum diameter of 13 mm in the right M2. Internal trapping using detachable coil were successfully performed, following which he was discharged without significant neurological deficit after one month of onset. Thus, we have reported a rare case of a large ruptured dissecting IA in a 3-month-old infant, in the right middle cerebral artery (MCA), successfully treated with an endovascular therapy, along with a literature review.

DOI： 10.2176/jns-nmc.2022-0369