Faculty Profiles - SAITO Ryuta

Postoperative fragmentation and distal migration of Carotid Stent in vascular Eagle Syndrome☆

Nishihori, M; Izumi, T; Goto, S; Muraoka, S; Kogame, H; Saito, R

JOURNAL OF STROKE & CEREBROVASCULAR DISEASES Vol. 34 ( 2 ) page： 108202 2025.2

Hemorrhagic complication due to vascular side branch injury from a distant site in stereoelectroencephalography: A case report and proposed rules for safer electrode implantation.

Suzuki T, Ishizaki T, Maesawa S, Hashida M, Ito Y, Tanei T, Saito R

Seizure Vol. 125 page： 50 - 53 2025.2

Evaluation of mild cognitive impairment in older patients with essential tremor. International journal

Miki Hashida, Satoshi Maesawa, Satomi Mizuno, Sachiko Kato, Yoshiki Ito, Manabu Mutoh, Takahiro Suzuki, Tomotaka Ishizaki, Takafumi Tanei, Takashi Tsuboi, Masashi Suzuki, Daisuke Nakatsubo, Takahiko Tsugawa, Epifanio Bagarinao, Toshihiko Wakabayashi, Masahisa Katsuno, Ryuta Saito

Parkinsonism & related disorders Vol. 131 page： 107228 - 107228 2025.2

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

INTRODUCTION: Recent studies have reported that essential tremor (ET) presents with not only motor symptoms but also cognitive dysfunction. However, detailed pathological mechanisms remain unclear. Here, we evaluate the characteristics of cognitive changes in older patients. METHODS: Eighty-five patients aged 65 years or older with ET but without dementia were evaluated for cognitive function using the Addenbrooke Cognitive Examination Revised (ACE-R). The patients were compared with healthy controls (HCs), and the characteristics of cognitive dysfunction were examined. Age at onset and correlations with tremor severity were also investigated. Moreover, we performed resting-state network (RSNs) analysis in a subset of these patients, and the functional connectivity (FC) within the networks was compared with age-matched controls. RESULTS: Compared to HCs, older patients with ET showed a clear reduction in the total (p = 0.001), attention (p = 0.005), verbal fluency (p = 0.001), and memory (p = 0.001) ACE-R scores. Older-onset patients showed significant cognitive dysfunction compared with younger-onset patients. Verbal fluency correlated with tremor severity in the multiple regression analysis (p < 0.001). RSNs showed an increase in FC in the frontal lobes within the language network in patients with ET compared to HCs (p < 0.05, FWE-corrected). CONCLUSION: Older patients with ET showed obvious cognitive dysfunction compared to HCs, indicating that cognitive dysfunction varies by age of onset and correlates with tremor severity. The results of the RSNs analysis suggest that the pathological mechanism of cognitive dysfunction in ET patients involves network changes similar to those in the early stages of Alzheimer's disease.

DOI： 10.1016/j.parkreldis.2024.107228

Residual Pattern of the Hyperintense Area on T2-Weighted Magnetic Resonance Imaging After Initial Treatment Predicts the Pattern and Location of Recurrence in Patients with Newly Diagnosed Glioblastoma. Reviewed International journal

Yoshiteru Shimoda, Masayuki Kanamori, Shota Yamashita, Ichiyo Shibahara, Rei Umezawa, Shunji Mugikura, Keiichi Jingu, Ryuta Saito, Yukihiko Sonoda, Toshihiro Kumabe, Hidenori Endo

World neurosurgery Vol. 193 page： 517 - 532 2025.1

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

OBJECTIVE: This study examined the clinical significance of residual hyperintense area on T2-weighted magnetic resonance imaging (T2R) without gadolinium-enhanced lesions at the end of initial treatment (debulking surgery, concomitant radiotherapy, and temozolomide) in patients with glioblastoma. METHODS: Among 150 glioblastoma cases, 77 cases without enhanced lesions at the end of initial treatment and without factors modifying the distribution of residual hyperintense area or pattern of recurrence were included. We retrospectively reviewed the relationship of residual hyperintense area after initial treatment with progression-free survival (PFS), overall survival (OS), and pattern of recurrence. RESULTS: In these 77 cases, the median PFS and OS were 12.4 and 27.4 months, respectively. At the end of initial treatment, 55 (71.4%) cases had residual hyperintense area (T2 residual group, T2R), whereas 22 (28.6%) showed no hyperintense area (T2 disappeared group, disappeared hyperintense area on T2-weighted magnetic resonance imaging [T2D]). Based on univariate and multivariate analyses, the residual hyperintense area after initial treatment was not a prognostic factor for PFS or OS. Distant recurrences occurred more frequently in the T2D group than in the T2R group 50.0% versus 9.5%. In the T2R group, the recurrence site coincided with the residual hyperintense area in 36 (85.7%) of 42 recurrences. CONCLUSIONS: The T2R at the end of initial treatment can predict local recurrence. However, the distant recurrence occurred frequently in T2D group. Thus, attention should be paid to local recurrences in T2R group and distant recurrences in T2D group.

DOI： 10.1016/j.wneu.2024.10.012

Endoscopic Cystoventricular Stenting in Awake Patients with ESM for Convexity Cysts: Three Case Reports and a Systematic Review. Reviewed International journal

Eriko Okumura, Kazuhito Takeuchi, Yuichi Nagata, Kenichiro Iwami, Kazuya Motomura, Fumiharu Ohka, Yoshiki Sato, Toshiaki Hirose, Ryuta Saito

World neurosurgery Vol. 193 page： 108 - 118 2025.1

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

Surgical interventions for arachnoid cysts and glioependymal cysts primarily focus on cyst decompression and establishing communication with cerebrospinal fluid (CSF) spaces. However, a standardized surgical strategy for symptomatic convexity cysts lacking surrounding CSF space is still lacking due to the limited number of cases. This systematic review aims to evaluate surgical interventions for symptomatic convexity cysts and proposes a safe and effective treatment approach we have developed. A systematic review of the literature was conducted following PRISMA guidelines. Surgical techniques were categorized into cystoperitoneal (CP) shunt, cyst excision, cyst fenestration, cyst ventriculostomy, and several uniquely modified methods. Using a method different from these previous reports, we performed endoscopic cystoventricular stenting via burr hole in three cases of convexity cysts. While traditional methods have proven effective, CP shunt may lead to malfunction, infection, and subdural hematoma; wall excision is invasive and increases morbidity risks. Fenestration and cystoventriculostomy have also reported cases of recurrence. Other methods also pose issues, including off-label use of instruments and inadequate consideration for removal. The method we performed for placing the stent catheter with multiple side holes demonstrated long-term effectiveness. Furthermore, the surgery was conducted with the patient fully awake, and the use of electrical stimulation mapping enabled preservation of higher neurocognitive functions, including language, working memory, and spatial cognition, at the puncture site. This novel approach offers advantages such as minimally invasive procedure, preservation of safe brain function, and long-term patency. Further studies are warranted to validate these findings and improve surgical strategies for convexity cysts.

DOI： 10.1016/j.wneu.2024.10.031

Efficacy and safety of carmustine wafers, followed by radiation, temozolomide, and bevacizumab therapy, for newly diagnosed glioblastoma with maximal resection

Kanamori, M; Shibahara, I; Shimoda, Y; Akiyama, Y; Beppu, T; Ohba, S; Enomoto, T; Ono, T; Mitobe, Y; Hanihara, M; Mineharu, Y; Ishida, J; Asano, K; Yoshida, Y; Natsumeda, M; Nomura, S; Abe, T; Yonezawa, H; Katakura, R; Shibui, S; Kuroiwa, T; Suzuki, H; Takei, H; Matsushita, H; Saito, R; Arakawa, Y; Sonoda, Y; Hirose, Y; Kumabe, T; Yamaguchi, T; Endo, H; Tominaga, T

INTERNATIONAL JOURNAL OF CLINICAL ONCOLOGY Vol. 30 ( 1 ) page： 51 - 61 2025.1

特集頸椎神経根症再考頸椎神経根症に対する頸椎前方固定術

西村由介, 永島吉孝, 齋藤竜太

脊椎脊髄ジャーナル Vol. 37 ( 11 ) page： 993 - 1000 2024.12

A case of traumatic middle meningeal artery pseudoaneurysm presenting with an intracerebral hematoma

Ishikawa Kojiro, Wakabayashi Kenichi, Ohito Masato, Mizuno Shohei, Ienaga Jumpei, Kawaguchi Tomomi, Nakamura Shigekazu, Tanei Takafumi, Saito Ryuta

Neurotraumatology Vol. 47 ( 2 ) page： 94 - 100 2024.12

Language：Japanese Publisher：The Japan Society of Neurotraumatology

Although various types of vascular disorders are associated with head trauma, a rare case is a traumatic middle meningeal artery pseudoaneurysm (tMMAP). We report a case of a 70–year–old man with tMMAP presenting with an intracerebral hematoma (ICH). He was rushed to the hospital in a poor state of consciousness after a traumatic fall. A computer tomography (CT) scan taken on admission revealed a traumatic left temporal lobe ICH, subarachnoid hemorrhage, and bilateral acute subdural hematoma. After conservative treatment, his consciousness improved, except for disorientation on day 3 of hospitalization, and a CT scan revealed resolution of ICH. However, on day 10 of hospitalization, he suddenly fell into a coma, and a CT scan revealed that the hematoma in the left temporal lobe had grown and caused a midline shift. We conducted an emergency craniotomy and hematoma removal, during which we encountered an intractable arterial bleeding at the left middle skull base. We could barely stop the bleeding using aneurysmal clips. Suspecting the possibility of a vascular abnormality, we performed a postoperative cerebral angiography that revealed a pseudoaneurysm in the left middle meningeal artery. We determined that this pseudoaneurysm was the source of the bleeding and performed an endovascular parent vessel occlusion. After the endovascular surgery, there was no recurrence of hemorrhage. The patient was transferred to a rehabilitation facility because of residual cognitive dysfunction. tMMAP is a rare disorder, and its rupture generally causes an epidural hematoma; however, in some cases, it can cause an ICH. Although it is difficult to predict the rupture in advance, tMMAP must be recognized as a delayed complication of traumatic vascular disorders as it can lead to severe conditions.

DOI： 10.32187/neurotraumatology.47.2_94

CiNii Research

A multi-center, open-label, randomized clinical trial evaluating the preventive effect of perampanel on craniotomy-induced epileptogenesis in seizure-naive patients with supratentorial brain tumors: study protocol for a GRAMPAS trial. International journal Open Access

Junya Yamaguchi, Fumiharu Ohka, Kazuya Motomura, Tomotaka Ishizaki, Norimoto Nakahara, Shigeru Fujitani, Tetsuya Nagatani, Masasuke Ohno, Masahiko Ando, Yachiyo Kuwatsuka, Kazuki Nishida, Ryuta Saito

Trials Vol. 25 ( 1 ) page： 849 - 849 2024.12

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

BACKGROUND: Early seizures after craniotomy are significant perioperative complications that can adversely impact patient outcomes. Despite current guidelines advising against the routine use of antiseizure drugs for seizure after craniotomy prevention due to limited efficacy data, many clinicians continue prescribing them. This discrepancy highlights the need for robust evidence to guide clinical practice. This multi-center, randomized clinical trial was designed to investigate the efficacy of perampanel in preventing early seizures after craniotomy. METHOD: This multi-center, open-label, randomized clinical trial will be conducted across five hospitals in Nagoya, Japan, from February 2024 to December 2026. A total of 142 seizure-naive patients with supratentorial brain tumors will be recruited and randomized (1:1) into the treatment and control groups. The treatment group will receive 2 mg of perampanel starting 2 days preoperatively and continuing for 28 days postoperatively, while the control group will receive no antiseizure drugs. The primary outcome is the incidence of seizures within 28 days after craniotomy. Secondary outcomes are length of hospital and intensive care unit stays and postoperative complications. DISCUSSION: This study addresses the critical need for evidence-based recommendations regarding antiseizure drug use for preventing early seizures after craniotomy. As the first multi-center, randomized trial evaluating perampanel's efficacy in this setting, the findings may significantly influence clinical guidelines and perioperative practices. TRIAL REGISTRATION: This trial was registered with the Japan Registry of Clinical Trials (approval number: jRCTs041230117) on December 18, 2023, a member of the Primary Registry Network of the World Health Organization's International Clinical Trials Registry Platform.

DOI： 10.1186/s13063-024-08693-7

Isolation of ependymal cilia from mouse brain( vol 409, 110198, 2024) Reviewed

Mizuno, A; Takeuchi, K; Nagata, Y; Harada, H; Yamamoto, T; Ishikawa, T; Maeda, S; Ohka, F; Ueno, H; Saito, R

JOURNAL OF NEUROSCIENCE METHODS Vol. 412 page： 110293 2024.12

Language：English Publisher：Journal of Neuroscience Methods

The authors regret that the affiliation information was incomplete in the original article. The correct and complete affiliation information should be as follows: Akihiro Mizunoa,b a Department of Neurosurgery, Komaki City Hospital, Aichi, Japan b Department of Neurosurgery, Nagoya University, Nagoya, Japan This research was conducted while the author was affiliated with Nagoya University. The addition of this affiliation is important for accurately reflecting the research context. The authors would like to apologize for any inconvenience caused.

DOI： 10.1016/j.jneumeth.2024.110293

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