研究者詳細 - 小松　克也

論文 - 小松　克也

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Clinical significance of intraoperative bidirectional corticocortical evoked potential monitoring to evaluate language function.

Chie Kamada, Yusuke Kimura, Shoto Yamada, Ryohei Saito, Katsuya Komatsu, Rei Enatsu, Yukinori Akiyama, Nobuhiro Mikuni

Journal of neurosurgery 1 - 9 2025年01月 [国際誌]

OBJECTIVE: Awake craniotomy is commonly used to resect lesions located near the language area during brain surgery. However, it is often difficult to perform language tasks due to several limitations such as difficulty in awakening during surgery and intraoperative seizures. This study investigated the clinical significance of bidirectional corticocortical evoked potential (CCEP) monitoring as a new approach to evaluate intraoperative language function. METHODS: This study enrolled 12 patients who underwent awake brain tumor resection with intraoperative CCEP monitoring to assess language function. Electrodes were placed on the frontal and temporoparietal lobes based on the location of the arcuate fasciculus identified with preoperative diffusion tensor imaging to measure CCEPs intraoperatively in two directions: from the frontal lobe to the temporoparietal lobe of the language-dominant side, and vice versa. Correlations between CCEP amplitudes or latencies before and after tumor removal in each direction and postoperative language function assessed with the Western Aphasia Battery were analyzed. RESULTS: Nine of the 12 patients showed language-related CCEP responses in both directions before, during, and after tumor removal. One patient who showed decreased CCEP amplitudes in both directions after tumor removal exhibited aphasia for as long as 1 month postoperatively. In contrast, of the 6 patients whose CCEP amplitude in only a single direction was reduced or disappeared, 4 had no deterioration of language function and the other 2 had temporary deterioration of language function during the 1st postoperative week, which improved by 1 month postoperatively. CONCLUSIONS: This study indicated that bidirectional CCEP measurement may increase the precision of intraoperative language function monitoring.

【脳卒中外科の手術手技】Off-the-job trainingによる手術技術獲得の促進若手術者によるSTA-MCA bypassの現状

山岡歩, 三上毅, 古明地孝宏, 能代将平, 大瀧雅文, 對馬州一, 小松克也, 金相年, 秋山幸功, 三國信啓

脳卒中の外科 ( (一社)日本脳卒中の外科学会 ) 52 ( 6 ) 433 - 439 2024年11月

若手術者が経験できるSTA-MCA bypassの症例数はかぎられており,手術技術の獲得にはoff-the-job training(OJT)が重要である.自身の練習方法と手術成績から,若手術者の手術技術の獲得方法を考察した.筆者がOJTとして実施した模擬血管による端側吻合練習に関する研究である.吻合のセットアップを重視し,練習の中で各段階の右手と左手の役割を決め,無駄のない手技の順序を考え続けた.実際の手術を想定し,血管径や術野の深さを変更した.4年間で807本の練習を行い,10例12本のSTA-MCA bypassを経験した.119本の練習後に模擬血管の吻合時間が20分未満に短縮し,その後のlearning curveはなだらかになった.練習条件の変更で一時的に吻合時間が延長したが,比較的速やかに短縮した.練習本数と手術における中大脳動脈の遮断時間の間には,累乗近似曲線で高い相関を認めた(r=0.90).経験症例5例目で,遮断時間20分未満を達成した.9例目ではトラブルがあったが,遮断時間は20分未満であった.徹底した反復練習で,吻合操作のスピードが向上しただけでなく,トラブルを仮想体験することで,冷静に対処する能力が養われた.練習による遮断時間の短縮が示唆されたが,練習継続の難しさは課題である.練習方法を一定に保ちながら,飽きや慣れが生じないよう工夫し,「習慣化」を図る必要がある.(著者抄録)

Deep learning from head CT scans to predict elevated intracranial pressure.

Ryota Sato, Yukinori Akiyama, Takeshi Mikami, Ayumu Yamaoka, Chie Kamada, Kyoya Sakashita, Yasuhiro Takahashi, Yusuke Kimura, Katsuya Komatsu, Nobuhiro Mikuni

Journal of neuroimaging : official journal of the American Society of Neuroimaging 2024年10月 [国際誌]

BACKGROUND AND PURPOSE: Elevated intracranial pressure (ICP) resulting from severe head injury or stroke poses a risk of secondary brain injury that requires neurosurgical intervention. However, currently available noninvasive monitoring techniques for predicting ICP are not sufficiently advanced. We aimed to develop a minimally invasive ICP prediction model using simple CT images to prevent secondary brain injury caused by elevated ICP. METHODS: We used the following three methods to determine the presence or absence of elevated ICP using midbrain-level CT images: (1) a deep learning model created using the Python (PY) programming language; (2) a model based on cistern narrowing and scaling of brainstem deformities and presence of hydrocephalus, analyzed using the statistical tool Prediction One (PO); and (3) identification of ICP by senior residents (SRs). We compared the accuracy of the validation and test data using fivefold cross-validation and visualized or quantified the areas of interest in the models. RESULTS: The accuracy of the validation data for the PY, PO, and SR methods was 83.68% (83.42%-85.13%), 85.71% (73.81%-88.10%), and 66.67% (55.96%-72.62%), respectively. Significant differences in accuracy were observed between the PY and SR methods. Test data accuracy was 77.27% (70.45%-77.2%), 84.09% (75.00%-85.23%), and 61.36% (56.82%-68.18%), respectively. CONCLUSIONS: Overall, the outcomes suggest that these newly developed models may be valuable tools for the rapid and accurate detection of elevated ICP in clinical practice. These models can easily be applied to other sites, as a single CT image at the midbrain level can provide a highly accurate diagnosis.

An anatomo-functional study of the interactivity between the paracentral lobule and the primary motor cortex.

Yusuke Kimura, Shoto Yamada, Katsuya Komatsu, Rei Enatsu, Ryota Sato, Chie Kamada, Ayaka Sasagawa, Tsukasa Hirano, Masayasu Arihara, Nobuhiro Mikuni

Journal of neurosurgery 1 - 9 2024年05月 [国際誌]

OBJECTIVE: The purpose of this study was to understand the anatomical and functional connections between the paracentral lobule (PCL) and the primary motor cortex (M1) of the human brain. METHODS: This retrospective study included 16 patients who underwent resection of lesions located near M1. Nine patients had lesions in the dominant hemisphere. Tractography was performed to visualize the connectivity between two regions of interest (ROIs)-the convexity and the interhemispheric fissure-that were shown by functional MRI to be activated during a finger tapping task. The number, mean length, and fractional anisotropy (FA) of the fibers between the ROIs were estimated. During surgery, subdural electrodes were placed on the brain surface, including the ROIs, using a navigation system. Cortico-cortical evoked potentials (CCEPs) were evoked by applying electrical stimuli to the hand region of M1 using electrodes placed on the convexity and were measured with electrodes placed on the interhemispheric fissure. To verify CCEP bidirectionality, electrical stimuli were applied to electrodes on the interhemispheric fissure that showed CCEP responses. Correlations of CCEP amplitudes and latencies with the number, mean length, and mean FA value obtained from tractography were determined. The correlations between these parameters and perioperative motor functions were also analyzed. RESULTS: Fibers of 14 patients were visualized by diffusion tensor imaging (DTI). Unidirectional CCEPs between the PCL and M1 were measurable in all 16 patients, and bidirectional CCEPs between them were measurable in 14 patients. There was no significant difference between the two directions in the maximum CCEP amplitude or latency (amplitude, p = 0.391; latency, p = 0.583). Neither the amplitude nor latency showed any apparent correlation with the number, mean length, or mean FA value of the fibers obtained from tractography. Pre- and postoperative motor function of the hands was not significantly correlated with CCEP amplitude or latency. The number and mean FA value of fibers obtained by DTI, as well as the maximum CCEP amplitude, varied between patients. CONCLUSIONS: This study demonstrated an anatomical connection and a bidirectional functional connection between the PCL, including the supplementary motor area, and M1 of the human brain. The observed variability between patients suggests possible motor function plasticity. These findings may serve as a foundation for further studies.

[Usefulness of Preoperative Simulation: Skull Base Approach].

Masahiko Wanibuchi, Toru Hirano, Toshihiro Takami, Shinji Kawabata, Motomasa Furuse, Naosuke Nonoguchi, Masahiro Kameda, Ryo Hiramatsu, Ryokichi Yagi, Gen Futamura, Masao Fukumura, Takuya Kosaka, Yusuke Fukuo, Katsuya Komatsu, Nobuhiro Mikuni

No shinkei geka. Neurological surgery 52 ( 2 ) 320 - 326 2024年03月 [国内誌]

Preoperative simulation images creates an accurate visualization of a surgical field. The anatomical relationship of the cranial nerves, arteries, brainstem, and related bony protrusions is important in skull base surgery. However, an operator's intention is unclear for a less experienced neurosurgeon. Three-dimensional(3D)fusion images of computed tomography and magnetic resonance imaging created using a workstation aids precise surgical planning and safety management. Since the simulation images allows to perform virtual surgery, a déjà vu effect for the surgeon can be obtained. Additionally, since 3D surgical images can be used for preoperative consideration and postoperative verification, discussion among the team members is effective from the perspective of surgical education for residents and medical students. Significance of preoperative simulation images will increase eventually.

Combined endoscopic endonasal and transcranial approach for internal carotid artery aneurysms: usefulness and safety of endonasal proximal control.

Ryota Sato, Yukinori Akiyama, Takeshi Mikami, Yuka Kawata, Chie Kamada, Yusuke Kimura, Katsuya Komatsu, Nobuhiro Mikuni

Neurosurgical review 46 ( 1 ) 283 - 283 2023年10月 [国際誌]

It is necessary to secure both the proximal and distal sides of the parent artery to prevent premature rupture when clipping cerebral aneurysms. Herein, we describe four cases in which the proximal internal carotid artery (ICA), affected by a paraclinoid aneurysm, was secured using an endoscopic endonasal approach. We used various tools, including a surgical video, cadaver dissection picture, artist's illustration, and intraoperative photographs, to elucidate the process. No patient experienced postoperative complications at our institution. Compared to the cervical or cavernous ICA, the ICA adjacent to the clivus (paraclival ICA) can be anatomically safely and easily exposed using an endoscopic endonasal approach because there is no need to consider cerebrospinal fluid leakage or hemorrhage from the cavernous sinus. Securing the proximal side of the parent artery using an endoscopic endonasal approach may be a viable method for clipping selected ICA aneurysms, such as paraclinoid aneurysms especially for upward or outward aneurysms of the C2 portion.

Microbleeds Due to Reperfusion Enhance Early Seizures after Carotid Ligation in a Rat Ischemic Model.

Takuro Saito, Takeshi Mikami, Tsukasa Hirano, Hiroshi Nagahama, Rei Enatsu, Katsuya Komatsu, Satoshi Okawa, Yukinori Akiyama, Nobuhiro Mikuni

Neurologia medico-chirurgica 63 ( 6 ) 228 - 235 2023年06月 [国内誌]

Impaired reperfusion in ischemic brain disease is a condition that we are increasingly confronted with owing to recent advances in reperfusion therapy. In the present study, rat models of reperfusion were investigated to determine the causes of acute seizures using magnetic resonance imaging (MRI) and histopathological specimens. Rat models of bilateral common carotid artery ligation followed by reperfusion and complete occlusion were created. We compared the incidence of seizures, mortality within 24 h, MRI, and magnetic resonance spectroscopy (MRS) to evaluate ischemic or hemorrhagic changes and metabolites in the brain parenchyma. In addition, the histopathological specimens were compared with those observed on MRI. In multivariate analysis, the predictive factors of mortality were seizure (odds ratios (OR), 106.572), reperfusion or occlusion (OR, 0.056), and the apparent diffusion coefficient value of the striatum (OR, 0.396). The predictive factors of a convulsive seizure were reperfusion or occlusion (OR, 0.007) and the number of round-shaped hyposignals (RHS) on susceptibility-weighted imaging (SWI) (OR, 2.072). The incidence of convulsive seizures was significantly correlated with the number of RHS in the reperfusion model. RHS on SWI was confirmed pathologically as microbleeds in the extravasation of the brain parenchyma and was distributed around the hippocampus and cingulum bundle. MRS analysis showed that the N-acetyl aspartate level was significantly lower in the reperfusion group than in the occlusion group. In the reperfusion model, RHS on SWI was a risk factor for convulsive seizures. The location of the RHS also influenced the incidence of convulsive seizures.

Transcranial electrical stimulation technique for induction of unilateral motor evoked potentials

Shoto Yamada, Rei Enatsu, Shu Ishikawa, Yusuke Kimura, Katsuya Komatsu, Tomohiro Chaki, Yukinori Akiyama, Takeshi Mikami, Nobuhiro Mikuni

Clinical Neurophysiology 150 194 - 196 2023年04月 [国際誌]

OBJECTIVE: Transcranial electrical stimulation motor evoked potentials (TES-MEP) are widely used to monitor motor function; however, broad current spread and induced body movement are limitations of this technique. We herein report a localized stimulation technique for TES-MEP that induces unilateral MEP responses. METHODS: The stimulation of C1(+)-C4(-) or C2(+)-C3(-) was performed to induce right- or left-sided muscle contraction, respectively, in 70 patients. Electromyography was recorded by placing electrodes on the bilateral abductor pollicis brevis (APB) and abductor hallucis (AH) muscles. Stimulation conditions were regulated in the range to induce unilateral muscle contractions contralateral to the anodal stimulation. The thresholds and amplitudes of TES-MEP were retrospectively analyzed. RESULTS: The thresholds of APB were lower than those of AH in 47 patients, AH thresholds were lower than those of APB in 6 patients, and both APB and AH started to respond at the same intensity in 15 patients. This technical stimulation induced contralateral limb contractions with a suprathreshold stimulation of 129.4 ± 35.6 mA (mean ± standard deviation) in 68 patients (97%). Amplitudes in the suprathreshold stimulation of APB and AH responses were 727.5 ± 695.7 and 403.3 ± 325.7 μV, respectively. CONCLUSIONS: The C1(+)-C4/C2(+)-C3(-) stimulation in TES-MEP enables a localized stimulation to induce unilateral MEP responses. SIGNIFICANCE: Our stimulation technique enables the stable and safe monitoring of unilateral limbs, and contributes to the reliable monitoring of motor function in neurosurgery.

A practical protocol for high-spatial-resolution magnetic resonance angiography for cerebral arteries in rats.

Hiroshi Nagahama, Masanori Sasaki, Katsuya Komatsu, Kaori Sato, Yoshimi Katagiri, Masaki Kamagata, Yuko Kataoka-Sasaki, Shinichi Oka, Ryo Ukai, Takahiro Yokoyama, Kojiro Terada, Masato Kobayashi, Jeffery D Kocsis, Osamu Honmou

Journal of neuroscience methods ( Elsevier {BV} ) 386 109784 - 109784 2023年01月 [国際誌]

BACKGROUND: Magnetic resonance angiography (MRA) is an important tool in rat models of cerebrovascular disease. Although MRA has long been used in rodents, the image quality is typically not as high as that observed in clinical practice. Moreover, studies on MRA image quality in rats are limited. This study aimed to develop a practical high-spatial-resolution MRA protocol for imaging cerebral arteries in rats. NEW METHOD: We used the "half position method" regarding coil placement and modified the imaging parameters and image reconstruction method. We applied this new imaging method to measure maturation-related signal changes on rat MRAs. RESULTS: The new practical high-spatial-resolution MRA imaging protocol obtained a signal intensity up to 3.5 times that obtained using a basic coil system, simply by modifying the coil placement method. This method allowed the detection of a gradual decrease in the signal in cerebral vessels with maturation. COMPARISON WITH EXISTING METHODS: A high-spatial-resolution MRA for rats was obtained with an imaging time of approximately 100 min. Comparable resolution and image quality were obtained using the new protocol with an imaging time of 30 min CONCLUSIONS: The new practical high-spatial-resolution MRA protocol can be implemented simply and successfully to achieve high image quality with an imaging time of approximately 30 min. This protocol will benefit researchers performing MRA imaging in cerebral artery studies in rats.

Computational Fluid Dynamics Analysis Features in Aneurysm Development in Rats

Shoichi KOMURA, Katsuya KOMATSU, Takeshi MIKAMI, Yukinori AKIYAMA, Sangnyon KIM, Rei ENATSU, Hiroshi NAGAHAMA, Nobuhiro MIKUNI

Neurologia medico-chirurgica ( Japan Neurosurgical Society ) 63 ( 6 ) 250 - 257 2023年 [国内誌]

The investigation of how to control the development and growth of cerebral aneurysms is important for the prevention of subarachnoid hemorrhage. Although there have been several types of research studies on computational fluid dynamics (CFD) analysis of brain aneurysm development and growth, there has been no unified interpretation of the CFD analysis results. The purpose of this study is to clarify the characteristics of CFD analysis results related to the development of cerebral aneurysms using an animal model. Nineteen rat models of cerebral aneurysms were created, and the CFD analysis results between the cerebral aneurysm group [n = 10; the aneurysm was observed on magnetic resonance angiography (MRA) within 10 weeks after aneurysm induction surgery] and the nonaneurysm group (n = 9) were compared. All aneurysms were confirmed on the proximal segment of the left cerebral artery (P1), and the cross-sectional area and curvature of the left P1 were evaluated together. In the cerebral aneurysm group, there was a decrease in wall shear stress (WSS) that is consistent with the location of the aneurysm compared to the nonaneurysm group. The cross-sectional area of the left P1 gradually increased in the aneurysm group but not in the nonaneurysm group. The mean curvature in the entire left P1 was higher in the aneurysm group than in the nonaneurysm group. This study revealed that the development of cerebral aneurysms is due to changes in vascular morphology, namely, an increase in vessel diameter and a high curvature, and a decreased WSS consistent with the site of aneurysm development using this animal model.

Validity of Preoperative Screening Before Open-Heart Surgery in Reduction of Perioperative Ischemic Stroke.

Katsuya Komatsu, Takeshi Mikami, Yusuke Kimura, Yukinori Akiyama, Nobuyoshi Kawaharada, Nobuhiro Mikuni

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association 31 ( 8 ) 106584 - 106584 2022年08月 [国際誌]

OBJECTIVES: Cerebrovascular event after open-heart surgery is a critical complication and contributes to poor prognosis, including increased mortality. The purpose of this study is to investigate the appropriate preoperative risk assessment and monitoring for reducing the risk of ischemic stroke after open-heart surgery. MATERIALS AND METHODS: 184 patients who underwent surgery for valvular heart disease were included in this study. Near-infrared oxygen saturation monitoring (INVOS system) was performed during open-heart surgery. For the purpose of perioperative stroke risk assessment, we evaluated the clinical and radiological factors of the group that underwent preoperative consultation and the group that did not, and of the patients with and without postoperative ischemic stroke. RESULTS: Preoperative consultation was performed in 60 cases. Large vessel steno-occlusive disease was found in nine cases, of which three had undergone revascularization surgery. Cerebral infarction developed in four cases, all of which had no large vessel steno-occlusive disease. There was no significant association between the development of postoperative ischemic stroke and presence of large vessel steno-occlusive disease. Preoperative baseline INVOS value was significantly low in the ischemic stroke group (49.5 ± 12.5) compared to the non-ischemic stroke group (66.8 ± 10.0), (P = 0.012). CONCLUSIONS: In open-heart surgery for valvular heart disease, low preoperative baseline INVOS values were associated with cerebral ischemic stroke after surgery. The combination of appropriate preoperative screening for large vessel steno-occlusive disease and measurement of INVOS could be used as a simple and useful method in screening for the risk of ischemic stroke after open-heart surgery.

Effect of Early Surgical Intervention for Brain Tumors Associated with Epilepsy on the Improvement in Memory Performance.

Tsukasa Hirano, Hime Suzuki, Katsuya Komatsu, Aya Kanno, Yuusuke Kimura, Rei Enatsu, Satoko Ochi, Hirofumi Ohnishi, Nobuhiro Mikuni

Neurologia medico-chirurgica 62 ( 6 ) 286 - 293 2022年04月 [国内誌]

We evaluated the effect of early surgical intervention on the change in memory performance of patients with low-grade brain tumors associated with epilepsy. Twenty-three adult patients with low-grade brain tumors and epilepsy who underwent surgery at our institution between 2010 and 2019 were included. The Wechsler Memory Scale-Revised (WMS-R) was used to assess cognitive memory performance. Memory performance before and after surgery was retrospectively evaluated. In addition, the relationships among preoperative memory function, postoperative seizure outcome, preoperative seizure control, temporal lobe lesion, and change in memory function were examined. There were statistically significant improvements from median preoperative to postoperative WMS-R subscale scores for verbal memory, general memory, and delayed recall (p<0.001, p<0.001, and p=0.0055, respectively) regardless of preoperative sores and tumor location. Good postsurgical seizure control was associated with significant improvements in postoperative WMS-R performance. Our results indicated that early surgical intervention might improve postoperative memory function in patients with low-grade brain tumors and epilepsy.

Macrohistory of Moyamoya Disease Analyzed Using Artificial Intelligence

Tomoyoshi Kuribara, Yukinori Akiyama, Takeshi Mikami, Katsuya Komatsu, Yusuke Kimura, Yasuhiro Takahashi, Kyoya Sakashita, Ryohei Chiba, Nobuhiro Mikuni

Cerebrovascular Diseases ( S. Karger AG ) 1 - 14 2022年02月

<b><i>Introduction:</i></b> Moyamoya disease is characterized by progressive stenotic changes in the terminal segment of the internal carotid artery and the development of abnormal vascular networks called moyamoya vessels. The objective of this review was to provide a holistic view of the epidemiology, etiology, clinical findings, treatment, and pathogenesis of moyamoya disease. A literature search was performed in PubMed using the term “moyamoya disease,” for articles published until 2021. <b><i>Results:</i></b> Artificial intelligence (AI) clustering was used to classify the articles into 5 clusters: (1) pathophysiology (23.5%); (2) clinical background (37.3%); (3) imaging (13.2%); (4) treatment (17.3%); and (5) genetics (8.7%). Many articles in the “clinical background” cluster were published from the 1970s. However, in the “treatment” and “genetics” clusters, the articles were published from the 2010s through 2021. In 2011, it was confirmed that a gene called Ringin protein 213 (<i>RNF213)</i> is a susceptibility gene for moyamoya disease. Since then, tremendous progress in genomic, transcriptomic, and epigenetic profiling (e.g., methylation profiling) has resulted in new concepts for classifying moyamoya disease. Our literature survey revealed that the pathogenesis involves aberrations of multiple signaling pathways through genetic mutations and altered gene expression. <b><i>Conclusion:</i></b> We analyzed the content vectors in abstracts using AI, and reviewed the pathophysiology, clinical background, radiological features, treatments, and genetic peculiarity of moyamoya disease.

Effects of polarity of bipolar sensorimotor direct cortical stimulation on intraoperative motor evoked potentials

Shoto Yamada, Rei Enatsu, Yusuke Kimura, Katsuya Komatsu, Yukinori Akiyama, Takeshi Mikami, Satoko Ochi, Nobuhiro Mikuni

Clinical Neurophysiology ( Elsevier {BV} ) 132 ( 10 ) 2351 - 2356 2021年08月 [国際誌]

OBJECTIVE: The present study investigated the effects of the stimulus polarity and location of motor evoked potential (MEP) to establish a stimulation protocol. METHODS: Nineteen patients who intraoperatively underwent MEP in bipolar direct cortical stimulation were enrolled in the present study. Somatosensory evoked potentials (SEP) of the contralateral median nerve stimulation were recorded to determine stimulation sites. MEP was performed under two settings in all patients: 1. Anodal bipolar stimulation: an anode on the precentral gyrus and a cathode on the postcentral gyrus, 2. Cathodal bipolar stimulation: a cathode on the precentral gyrus and an anode on the postcentral gyrus. MEP amplitudes and the coefficient of variation (CV) at a stimulation intensity of 25 mA and the thresholds of induced MEP were compared between the two settings. RESULTS: An electrical stimulation at 25 mA induced a significantly higher amplitude in cathodal bipolar stimulation than in anodal bipolar stimulation. Cathodal bipolar stimulation also showed significantly lower thresholds than anodal stimulation. CV did not significantly differ between the two groups. CONCLUSIONS: These results indicate that cathodal bipolar stimulation is superior to anodal bipolar stimulation for intraoperative MEP monitoring. SIGNIFICANCE: MEP in cathodal bipolar cortical stimulation may be used in a safe and useful evaluation method of motor fiber damage that combines sensitivity and specificity.

Additional Revascularization Using Multiple Burr Holes for PCA Involvement in Moyamoya Disease.

Chie Kamada, Tsukasa Hirano, Takeshi Mikami, Katsuya Komatsu, Hime Suzuki, Syuichi Tsushima, Yukinori Akiyama, Nobuhiro Mikuni

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( Elsevier {BV} ) 30 ( 8 ) 105852 - 105852 2021年08月 [国際誌]

In specific cases of moyamoya disease (MMD), posterior cerebral artery (PCA) stenosis can develop after treatment of the anterior circulation and require additional revascularization. Here, we report two cases that underwent additional posterior indirect revascularization with multiple burr holes for PCA involvement after bilateral revascularization treatment of the anterior circulation. They presented with transient ischemic attack even after bilateral superficial temporal artery-middle cerebral artery bypass, and magnetic resonance angiography (MRA) showed that PCA stenosis had worsened. Indirect revascularization with multiple burr holes using Benz-marked skin incisions was performed. After surgery, the symptoms improved without perioperative complications, and cerebral angiography showed collateral circulation via the burr hole. Indirect revascularization for MMD is often combined with direct revascularization, and there are only a few reports on the use of multiple burr hole surgery alone. In addition, there are few reports of posterior circulation, despite the emphasis on the importance of PCA involvement in MMD. Indirect revascularization with multiple burr holes alone can be performed in multiple areas and applied to patients who cannot undergo direct revascularization using the occipital artery. The procedure is simple and less invasive than traditional direct revascularization procedures. Therefore, it can be effective, especially in pediatric cases of MMD with PCA involvement.

Aging-associated inflammation and fibrosis in arachnoid membrane.

Hime Suzuki, Takeshi Mikami, Naotoshi Iwahara, Yukinori Akiyama, Masahiko Wanibuchi, Katsuya Komatsu, Rintaro Yokoyama, Tsukasa Hirano, Ryusuke Hosoda, Yoshiyuki Horio, Atsushi Kuno, Nobuhiro Mikuni

BMC neurology 21 ( 1 ) 169 - 169 2021年04月 [国際誌]

BACKGROUND: The physiological and pathological significance of the arachnoid membrane (AM) is still unknown. In this study, we investigated various characteristics of the AM, focusing on the influence of inflammation and fibrosis. METHODS: Small pieces of AM sample were obtained during neurosurgical procedures from 74 cases. The clinical and pathological characteristics of the hyperplastic AM group (≥ 50 μm) and the non-hyperplastic AM group (< 50 μm) were compared. Then, potential correlations between AM thickness and clinical characteristics were analyzed. Moreover, VEGFα, TGFβ, and TGFα levels were quantitated by real time PCR. Then, the potential correlations between AM thickness and these inflammatory or anti-inflammatory markers, and the influence of the original disease were calculated. RESULTS: The median age of the patients in hyperplastic AM group was significantly older than that of the non-hyperplastic AM group. Moreover, the number of fibroblasts, CD68+ cells, CD86+ cells, and CD206+ cells in the hyperplastic AM group was significantly higher than that in the non-hyperplastic AM group. The AM thickness was significantly correlated to age and number of fibroblasts, CD68+ cells, CD86+ cells, and CD206+ cells. The thickness of the AM was significantly correlated to the messenger RNA expression levels of VEGFα (ρ = 0.337), and the VEGFα expression levels were significantly correlated with TGFβ and TNFα. CONCLUSIONS: The AM hyperplasia was influenced by aging and could be a result of inflammation and fibrosis through cytokine secretion from the inflammatory cells and fibroblasts in the AM.

COVID-19 infection in Hokkaido, Japan might depend on the viscosity of atmospheric air.

Yukinori Akiyama, Kyoya Sakashita, Masayasu Arihara, Yusuke Kimura, Katsuya Komatsu, Takeshi Mikami, Nobuhiro Mikuni

Virus research 293 198259 - 198259 2021年02月 [国際誌]

BACKGROUND: The large number of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has plunged the world into fear in recent times. In Japan, 18,769 novel coronavirus disease 2019 (COVID-19) cases have been reported as of June 30, 2020. This study aimed to assess whether cluster infection prevention is possible by evaluating the association between viral transmission and meteorological factors. METHODS: This study included 1263 people who were successively diagnosed with COVID-19 in Hokkaido, Japan between January 24, 2020 and June 30, 2020. After obtaining the values from the Japanese Meteorological Agency, the average scores of air temperature and humidity were calculated and compared with COVID-19 reproduction numbers, and the association between COVID-19 incidence or reproduction number and meteorological factors was assessed. RESULTS: The COVID-19 reproduction number in Hokkaido had three peaks that came several days before the surge in COVID-19 cases. The peaks are indicative of cluster infections. There was a strong negative correlation between the kinematic viscosity of atmospheric air and the reproduction number. DISCUSSION AND CONCLUSION: Analysis of the reproduction number is important for predicting or suppressing COVID-19 infection clusters. The authors found a strong association between meteorological factors, such as kinematic viscosity of atmospheric air and the incidence of COVID-19 infection. Meteorological forecasts could provide foreknowledge about COVID-19 infection clusters in the future.

Preoperative Prediction of Communication Difficulties during Awake Craniotomy in Glioma Patients: A Retrospective Evaluation of 136 Cases at a Single Institution.

Tomoyoshi Kuribara, Yukinori Akiyama, Takeshi Mikami, Yusuke Kimura, Katsuya Komatsu, Rei Enatsu, Yasuyuki Tokinaga, Nobuhiro Mikuni

Neurologia medico-chirurgica 61 ( 1 ) 21 - 32 2021年01月 [国内誌]

Awake craniotomy has been widely performed in patients with glioma in eloquent areas to minimize postoperative brain dysfunction. However, neurological examination in awake craniotomy is sometimes problematic due to communication difficulties during the intraoperative awake period. We evaluated preoperative predictors of these difficulties in awake craniotomy for patients with glioma. In all, 136 patients with glioma who underwent awake craniotomy at our institution between January 2012 and January 2020 were retrospectively evaluated. Patients were divided into two groups (appropriately awake group and inappropriately awake group) depending on their state during the intraoperative awake period, and the relationship between communication difficulties in awake craniotomy and both clinical and radiological characteristics were assessed. The appropriately awake group included 110 patients, and the inappropriately awake group included 26 patients. Reasons for inclusion in the inappropriately awake group were insufficient wakefulness in 15 patients, restless state in 6, and intraoperative seizures in 5. In multivariate analysis, the likelihood of being inappropriately awake was inversely correlated with preoperative seizures (odds ratio [OR], 0.23; 95% confidence interval [CI], 0.06-0.89; p = 0.033) and positively correlated with left-sided lesions (OR, 7.31; 95% CI, 1.54-34.62; p = 0.012). Both lack of preoperative seizures and left-sided lesions were identified as risk factors for intraoperative difficulties in awake craniotomy for patients with glioma. Understanding these risk factors may lead to more appropriate determination of eligibility for awake craniotomy.

Preoperatively estimated graft flow rate contributes to the improvement of hemodynamics in revascularization for Moyamoya disease.

Tomoyoshi Kuribara, Takeshi Mikami, Katsuya Komatsu, Yusuke Kimura, Sangnyon Kim, Kei Miyata, Yukinori Akiyama, Rei Enatsu, Toru Hirano, Nobuhiro Mikuni

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( Elsevier {BV} ) 30 ( 1 ) 105450 - 105450 2021年01月 [国際誌]

OBJECTIVES: Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass operation is an effective treatment for patients with Moyamoya disease, and the hemodynamic parameters are reported to be improved after operation. However, there is no report concerning hemodynamic changes from the viewpoint of the preoperative anatomical structure of grafts. In this study, we evaluated the correlation between the preoperatively estimated blood flow of the graft obtained through image-based computational fluid dynamics (CFD) analysis and the hemodynamic changes in the acute phase after revascularization. MATERIALS AND METHODS: A total of 30 hemispheric sides of 23 patients were examined. The blood flow, that is, flow rate (FR) of the STA branches that were anastomosed to the MCA was evaluated using CFD analysis based on computed tomography (CT) angiography imaging data. The correlations between the FR and the hemodynamic changes in the acute phase after revascularization obtained through CT perfusion were assessed. RESULTS: The preoperatively estimated FR of the graft was moderately correlated with the changes in the mean transit time significantly and weakly correlated with those in the cerebral blood flow and cerebral blood volume. In addition, the FR was strongly correlated with age and the diameter of the STA from the origin to the bifurcation. CONCLUSION: The preoperatively estimated FR of the graft obtained through image-based CFD analysis contributed to the improvement of the mean transit time after revascularization. Because the FR of the graft was associated with the diameter of the STA, the size of the STA might be an important factor in postoperative hemodynamic changes. This might lead to the risk assessment of acute drastic hemodynamic changes as cerebral hyperperfusion, and consequently, better surgical outcomes might be expected.

Changes in treatment strategy over time for arteriovenous malformation in a Japanese high-volume center.

Katsuya Komatsu, Yasushi Takagi, Akira Ishii, Takayuki Kikuchi, Yukihiro Yamao, Kazumichi Yoshida, Susumu Miyamoto

BMC neurology ( Springer Science and Business Media {LLC} ) 20 ( 1 ) 404 - 404 2020年11月 [国際誌]

BACKGROUND: Despite rapid developments in devices used to treat arteriovenous malformation (AVM), a randomised trial of Unruptured Brain Arteriovenous malformations published in 2014 recommended conservative treatment for nonhemorrhagic AVM. The purpose of the current retrospective study was to confirm how AVM treatment in Japan has changed and to assess the safety of treatment for hemorrhagic and nonhemorrhagic AVMs. METHODS: We enrolled 242 consecutive patients with AVM; each patient's treatment was selected and performed at our hospital. The type of onset, Spetzler-Martin (S-M) grade, age, sex, selected treatment, mortality, and morbidity were compared between the first and second periods of our study. RESULTS: In patients with grade I-III AVM, the selected treatment changed between the first and second periods; however, in grade IV and V patients, the selected treatment did not change. Overall, interventions by microsurgery alone decreased (p < 0.001), the proportion of total treatments including microsurgery decreased (p = 0.005), interventions using stereotactic radiosurgery (SRS) alone increased (p = 0.009), and interventions including SRS increased (p = 0.002). Morbidity associated with intervention was 0.92% in the first period and 0% in the second period, and mortality was 0.92% in the first period and 1.67% in the second. CONCLUSIONS: With the development of new devices, the selected treatment was changed in patients with S-M grade I-III AVM, but was not changed in patients with grade IV and V. The complication rate was low and did not change throughout the periods. These findings suggest that the safety of treatment depends on a full understanding of device development and the selection of proper treatment, not on hemorrhagic onset. Further treatment innovations are expected to change the treatment for grade IV and V AVMs.

Recurrence Interval Within 1 Year Leads to Death in Patients with Grade 2 Meningioma.

Ryo Ukai, Masahiko Wanibuchi, Katsuya Komatsu, Yusuke Kimura, Yukinori Akiyama, Takeshi Mikami, Nobuhiro Mikuni

World neurosurgery ( Elsevier {BV} ) 142 e58-e65 - e65 2020年10月 [査読有り] [国際誌]

OBJECTIVE: Grade 2 meningioma is more likely to recur than grade 1 meningioma. Recurrence decreases overall survival in patients with grade 2 meningioma. However, the clinical course of grade 2 meningioma with several repeated recurrences is poorly understood. The purpose of this study was to clarify the clinical characteristics of grade 2 meningioma with repeated recurrences. METHODS: This study included 28 patients with grade 2 meningioma treated at our institution from January 1994 to December 2017. The relationship between survival and factors including age, sex, number of recurrences, malignant transformation, radiation therapy, tumor location, MIB-1 labeling index, Simpson grade, Karnofsky Performance Status, and surgical interval were analyzed. RESULTS: The average age at the initial operation was 53.4 years. The number of recurrences was 3.7 times on average during the follow-up of 113.9 months after the initial operation. An increasing number of recurrences resulted in shortening of the surgical interval, increase in the MIB-1 labeling index, and decrease in Karnofsky Performance Status. In fatal cases, the average surgical interval before death was approximately 1 year. Three factors were related to poor prognosis: number of recurrences (odds ratio, 1.620; P = 0.030), malignant transformation (odds ratio, 10.625; P = 0.019), and high MIB-1 labeling index (odds ratio, 1.089; P = 0.044). CONCLUSIONS: Shortening of the surgical interval within 1 year because of multiple recurrences led to death in patients with grade 2 meningioma. Malignant transformation was the most potent among the poor prognostic factors.

Ischemic Tolerance Evaluated by Computed Tomography Perfusion during Balloon Test Occlusion.

Tomoyoshi Kuribara, Takeshi Mikami, Satoshi Iihoshi, Kei Miyata, Sangnyon Kim, Yuka Kawata, Katsuya Komatsu, Yusuke Kimura, Rei Enatsu, Yukinori Akiyama, Toru Hirano, Nobuhiro Mikuni

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( Elsevier {BV} ) 29 ( 6 ) 104807 - 104807 2020年06月 [査読有り] [国際誌]

OBJECTIVES: Balloon test occlusion (BTO) is performed to evaluate ischemic tolerance for large and giant cerebral aneurysms and head and neck tumors that may require parent artery occlusion. However, ischemic tolerance for the temporary test occlusion does not always guarantee a tolerance for permanent occlusion. In this study, we evaluated the utility of computed tomography (CT) perfusion during BTO to quantify ischemic tolerance for detecting delayed ischemic stroke. MATERIALS AND METHODS: Forty-one patients who underwent BTO for the internal carotid artery were included. The correlations between the parameters of CT perfusion and collateral angiographic appearance or stump pressure during BTO were evaluated. The cerebral blood flow (CBF), cerebral blood volume, mean transit time (MTT), and time to peak (TTP) were obtained through CT perfusion, and the asymmetry ratios were determined. Collateral angiographic appearances were categorized into 5 grades (0-4). RESULTS: The collateral angiographic appearance showed moderate correlations with CBF, MTT, and TTP that was significant. Of these, the absolute value of the correlation coefficient was the highest for MTT. MTT also showed a moderate correlation with stump pressure. CBF and MTT were significantly different between the poor collateral group (grades 2 and 3) and the good collateral group (grade 4). Based on the MTT, the good collateral group was identified with high sensitivity (75.0%) and specificity (81.2%). CONCLUSIONS: In BTO, the MTT obtained through CT perfusion showed a correlation with collateral angiographic appearance and stump pressure. Thus, the MTT might be useful to quantify ischemic tolerance for detecting delayed ischemic stroke.

Predictive factors for acute thrombogenesis occurring immediately after bypass procedure for moyamoya disease.

Takeshi Mikami, Hime Suzuki, Ryo Ukai, Katsuya Komatsu, Yukinori Akiyama, Masahiko Wanibuchi, Kiyohiro Houkin, Nobuhiro Mikuni

Neurosurgical review ( Springer Science and Business Media {LLC} ) 43 ( 2 ) 609 - 617 2020年04月 [査読有り] [国際誌]

Extracranial-to-intracranial (EC-IC) bypass surgery is an effective treatment for patients with moyamoya disease and other conditions. Some patients with moyamoya disease have a risk of acute thrombogenesis at the anastomotic site just after bypass surgery. The purpose of this study was to study risk factors of acute thrombogenesis and determine effective countermeasures. This study included 48 patients (66 EC-IC bypass procedures) with moyamoya disease and 52 controls (54 procedures) without moyamoya disease. The development of acute thrombogenesis was compared between the moyamoya disease and control groups. In the moyamoya disease group, clinical and radiological characteristics were assessed with respect to acute thrombogenesis. In the patients with acute thrombogenesis, causes of technical problems were retrospectively examined. The incidence of acute thrombogenesis was significantly higher in the moyamoya disease group than those in the control group. In the moyamoya disease group, acute thrombogenesis was observed in seven patients. In the moyamoya disease group, the magnetic resonance angiography (MRA) scores were significantly higher in patients with acute thrombogenesis than those in the patients without acute thrombogenesis. In the multivariate analysis, the predictive factor of acute thrombogenesis in moyamoya disease was a high MRA score (odds ratio, 2.336; p = 0.009). During EC-IC bypass surgery for moyamoya disease, acute thrombogenesis should be considered to obtain a high patency rate, particularly in patients with high MRA scores. Acute thrombogenesis will not influence morbidity if proper countermeasures are followed; therefore, the prediction and recognition of white thrombus are important for a successful bypass surgery.

Effectiveness of intraoperative visual evoked potential in avoiding visual deterioration during endonasal transsphenoidal surgery for pituitary tumors.

Kentaro Toyama, Masahiko Wanibuchi, Toshimi Honma, Katsuya Komatsu, Yukinori Akiyama, Takeshi Mikami, Nobuhiro Mikuni

Neurosurgical review 43 ( 1 ) 177 - 183 2020年02月 [査読有り] [国際誌]

Postoperative visual function is a major concern in transsphenoidal surgery (TSS). Although several reports have demonstrated the importance of visual evoked potential (VEP) monitoring during TSS, the usefulness of VEP monitoring have been controversial because of its reproducibility. Efficacy of VEP was analyzed in 20 consecutive cases of patients who underwent endoscopic endonasal TSS surgery. We adapted a high-power light-emitting diode stimulator with electroretinography using venous anesthesia. In addition, we used black shield patch and braided codes to obtain reproducible VEP amplitudes. Stable and reproducible VEP waveforms were obtained in 38 of 39 eyes (97.4%) before surgery. Fifteen eyes had deteriorated VEP amplitude during operation, and nine eyes had improved VEP amplitude at the end of surgery, and six eyes had not improved VEP amplitude. But no postoperative visual impairment was observed in all cases by temporary halting the surgical manipulation when the VEP was deteriorated. In conclusion, VEP monitoring could be a warning sign to avoid postoperative visual dysfunction. We recommend VEP as a routine monitoring in TSS.

Influence of Inflammatory Disease on the Pathophysiology of Moyamoya Disease and Quasi-moyamoya Disease.

Takeshi Mikami, Hime Suzuki, Katsuya Komatsu, Nobuhiro Mikuni

Neurologia medico-chirurgica ( Japan Neurosurgical Society ) 59 ( 10 ) 361 - 370 2019年10月 [査読有り] [国内誌]

Moyamoya disease is a unique cerebrovascular disease that is characterized by progressive bilateral stenotic alteration at the terminal portion of the internal carotid arteries. These changes induce the formation of an abnormal vascular network composed of collateral pathways known as moyamoya vessels. In quasi-moyamoya disease, a similar stenotic vascular abnormality is associated with an underlying disease, which is sometimes an inflammatory disease. Recent advances in moyamoya disease research implicate genetic background and immunological mediators, and postulate an association with inflammatory disease as a cause of, or progressive factor in, quasi-moyamoya disease. Although this disease has well-defined clinical and radiological characteristics, the role of inflammation has not been rigorously explored. Herein, we focused on reviewing two main themes: (1) molecular biology of inflammation in moyamoya disease, and (2) clinical significance of inflammation in quasi-moyamoya disease. We have summarized the findings of the former theme according to the following topics: (1) inflammatory biomarkers, (2) genetic background of inflammatory response, (3) endothelial progenitor cells, and (4) noncoding ribonucleic acids. Under the latter theme, we summarized the findings according to the following topics: (1) influence of inflammatory disease, (2) vascular remodeling, and (3) mechanisms gleaned from clinical cases. This review includes articles published up to February 2019 and provides novel insights for the treatment of the moyamoya disease and quasi-moyamoya disease.

Prevention of neointimal hyperplasia induced by an endovascular stent via intravenous infusion of mesenchymal stem cells.

Masahito Nakazaki, Shinichi Oka, Masanori Sasaki, Yuko Kataoka-Sasaki, Rie Onodera, Katsuya Komatsu, Satoshi Iihoshi, Manabu Hiroura, Akira Kawaguchi, Jeffery D Kocsis, Osamu Honmou

Journal of neurosurgery ( Journal of Neurosurgery Publishing Group ({JNSPG}) ) 133 ( 6 ) 1 - 13 2019年10月 [査読有り] [国際誌]

OBJECTIVE: In-stent restenosis after percutaneous transluminal angioplasty and stenting (PTAS) due to neointimal hyperplasia is a potential cause of clinical complications, including repeated revascularization and ischemic events. Neointimal hyperplasia induced by an inflammatory response to the stent strut may be a possible mechanism of in-stent restenosis. Intravenous infusion of bone marrow-derived mesenchymal stem cells (MSCs) has been reported to show therapeutic efficacy for cerebral stroke, presumably by an antiinflammatory effect. This study aimed to determine whether MSCs can reduce or prevent neointimal hyperplasia induced by an endovascular stent. METHODS: In this study, two types of bare metal stents were deployed using a porcine (mini-pig) model. One stent was implanted in the common carotid artery (CCA), which is considered quite similar to the human CCA, and the other was inserted in the superficial cervical artery (SCA), which is similar in size to the human middle cerebral artery. Angiographic images, intravascular ultrasound (IVUS) imaging, and microscopic images were used for analysis. RESULTS: Angiographic images and IVUS studies revealed that intravenous infusion of MSCs immediately after deployment of stents prevented in-stent stenosis of the CCA and SCA. Histological analysis also confirmed that inflammatory responses around the stent struts were reduced in both the stented CCA and SCA in the mini-pig. CONCLUSIONS: Intravenous infusion of MSCs inhibited the inflammatory reaction to an implanted stent strut, and prevented progressive neointimal hyperplasia in the stented CCA and SCA in a porcine model. Thus, MSC treatment could attenuate the recurrence of cerebral ischemic events after stenting.

Rare Case of Concurrent Glossopharyngeal and Trigeminal Neuralgia, in Which Glossopharyngeal Neuralgia was Possibly Induced by Postoperative Changes Following Microvascular Decompression for Trigeminal Neuralgia.

Yoshinori Maki, Takayuki Kikuchi, Katsuya Komatsu, Yasushi Takagi, Susumu Miyamoto

World neurosurgery ( Elsevier {BV} ) 130 150 - 153 2019年10月 [査読有り] [国際誌]

BACKGROUND: Glossopharyngeal neuralgia (GPN) and trigeminal neuralgia (TN) can result from mechanical stimulation of the glossopharyngeal nerve (GPNv) and trigeminal nerve (TNv) by blood vessels. TN can cause severe pain in the orofacial region, whereas GPN manifests as pain in the tongue, throat, tonsil, and ear. Although these 2 neuralgias can occur concurrently, concurrence of recurrent TN and GPN that develops postoperatively has not been previously described. CASE DESCRIPTION: A 68-year-old male complained of right glossalgia and pain in the pharynx radiating to the right auricular area. The patient had previously undergone microvascular decompression (MVD) for right TN. Medication and intraoral xylocaine spray did not relieve the symptoms. An oral surgeon was unable to find any disease related to the glossalgia. The anesthesiologist pointed out that the symptoms could be from partial recurrence of the TN because the patient also complained of pain in the inferior alveolus. Magnetic resonance angiography indicated that the right GPNv seemed to be compressed by the right posterior inferior cerebellar artery (PICA); hence, MVD for both GPN and TN was performed. Intraoperatively, the right PICA was found to be adherent to the GPNv because of the thickened arachnoid membrane and was subsequently detached. The TNv was also examined, but only a Teflon ball was found, which was detached from the TNv. The GPN disappeared postoperatively, although TN persisted after the second operation. CONCLUSIONS: GPN can result from adhesions between the GPNv and arachnoid membrane following previous MVD.

Vascular assessment after clipping surgery using four-dimensional CT angiography.

Yusuke Kimura, Takeshi Mikami, Kei Miyata, Hime Suzuki, Toru Hirano, Katsuya Komatsu, Nobuhiro Mikuni

Neurosurgical review ( Springer Verlag ) 42 ( 1 ) 107 - 114 2019年03月 [査読有り] [国際誌]

Recent advances in computed tomography angiography (CTA) enable repeated imaging follow up for post-clipping surgery. The purpose of this study was to clarify the critical volume and configuration of the aneurysmal clip in the postoperative evaluation using volume rendering (VR) imaging, and present four-dimensional (4D)-CTA for these larger metal artifacts. A total of 44 patients with cerebral aneurysm, treated using clipping surgery, were included in this study. The metal artifact volume was assessed using CTA and the association between the type of clips and its metal artifact volume was analyzed. A VR image and a 4D-CTA were then produced, and the diagnostic accuracy of arteries around the clip or residual aneurysm on these images was evaluated. In the receiver operating characteristic (ROC) curve analysis, the cutoff value for metal artifacts was 2.32 mm3 as determined through a VR image. Patients were divided into two groups. Group 1 included patients with a simple and small clip, and group 2 included patients with multiple, large or fenestrated clips. The metal artifact volume was significantly larger in group 2, and the group incorporated the cutoff value. Post-clipping status on the VR image was significantly superior in group 1 compared with group 2. In group 2, the imaging quality of post-clipping status on 4D-CTA was superior in 92.9% of patients. The metal artifact volume was dependent on the number, size, or configuration of the clip used. In group 2, evaluation using a 4D-CTA eliminated the effect of the metal artifacts.

[Possible Segmental Arterial Mediolysis Associated with Intraperitoneal Hemorrhage in the Acute Stage of Subarachnoid Hemorrhage:A Case Report].

Jiro Ohara, Yukihiro Yamao, Akira Ishii, Hironori Shimizu, Takayuki Kikuchi, Yohei Takenobu, Katsuya Komatsu, Hiroyuki Ikeda, Taku Inada, Hidehisa Nishi, Yu Abekura, Susumu Miyamoto

No shinkei geka. Neurological surgery 47 ( 1 ) 97 - 103 2019年01月 [査読有り] [国内誌]

Segmental arterial mediolysis(SAM)is a rare non-inflammatory and non-atherosclerotic arteriopathy associated with the occurrence of multiple aneurysms such as intracranial and intraperitoneal aneurysms. We report a case of intraperitoneal hemorrhage that occurred during the acute stage of subarachnoid hemorrhage(SAH). An 82-year-old woman presented with a sudden onset of loss of consciousness with a diagnosis of SAH. Digital subtraction angiography demonstrated two consecutive vertebral artery-posterior inferior cerebellar artery aneurysms. The larger aneurysm, which seemed to be ruptured, was successfully treated by coil embolization. On the 9th day after the onset of SAH, she developed aphasia secondary to the cerebral vasospasm. After selective intra-arterial infusion of fasudil hydrochloride, she was observed to maintain elevated systolic blood pressure. Her aphasia improved; however, on the 14th day, she suddenly developed hemorrhagic shock. An abdominal computed tomography scan demonstrated intraperitoneal hemorrhage secondary to a ruptured fusiform aneurysm of the right gastroepiploic artery. The lesion was successfully treated by coil embolization, although she became bedridden. Although a histopathological examination was not performed, her clinical, radiological, and serological presentation met the criteria of the clinical diagnosis of SAM. Elevated systolic blood pressure and excessive release of catecholamines in the acute stage of SAH might have caused the intraperitoneal hemorrhage. Non-saccular ruptured intracranial aneurysms should be considered among the differential diagnoses of SAM. In such cases, identifying and monitoring intraperitoneal aneurysms might be useful for earlier diagnosis and treatment of SAM, especially in the acute stage after SAH.

Ruptured intranidal aneurysm of an arteriovenous malformation diagnosed by delay alternating with nutation for tailored excitation (DANTE)–prepared contrast-enhanced magnetic resonance imaging

Katsuya Komatsu, Yasushi Takagi, Akira Ishii, Takayuki Kikuchi, Yukihiro Yamao, Yasutaka Fushimi, John Grinstead, Sinyeob Ahn, Susumu Miyamoto

Acta Neurochirurgica ( Springer Nature ) 160 ( 12 ) 2435 - 2438 2018年12月 [査読有り] [国際誌]

This case report describes the usefulness of delay alternating with nutation for tailored excitation (DANTE)-prepared, contrast-enhanced magnetic resonance imaging (CE-MRI) for detecting the rupture site of an arteriovenous malformation (AVM). A ruptured intranidal aneurysm was confirmed histopathologically. Accurate non-invasive information about the possible rupture site of an AVM is critical for optimal treatment and evaluation. Vessel wall enhancement visualized by DANTE-prepared CE-MRI may be a useful tool for providing information about changes in inflammatory status and vulnerability to further developments.

Surgical Anatomy of Rats for the Training of Microvascular Anastomosis.

Takeshi Mikami, Hime Suzuki, Ryo Ukai, Katsuya Komatsu, Yusuke Kimura, Yukinori Akiyama, Masahiko Wanibuchi, Nobuhiro Mikuni

World neurosurgery ( Elsevier {BV} ) 120 e1310-e1318 - e1318 2018年12月 [査読有り] [国際誌]

BACKGROUND: Microvascular anastomosis is an essential procedure in neurosurgery, but the opportunity to perform the surgery has gradually decreased for neurosurgeons. Therefore, training is necessary for obtaining and maintaining the skills required for the procedure. We describe the detailed anatomy of cervical and femoral regions in rats and discuss the advantages for practicing microvascular anastomosis. METHODS: Cervical regions of Sprague-Dawley rats were dissected under intraperitoneal anesthesia. The step-by-step anatomic description was documented using a high-resolution charge-coupled device image sensor and recording systems. Using this model, temporal occlusion time and patency were measured, and these measures were compared between the trainee and trainer groups. The number of times the training needs to be completed to attain competency in the bypass procedure was estimated. RESULTS: After exposing the carotid triangle, a half-ring was created by end-to-side anastomosis. Anastomosis was performed at the common carotid artery using the contralateral side of the carotid artery as a graft. The cutoff value for the temporal occlusion time was 79.3 minutes in the receiver operating characteristic curve based on a target temporal occlusion time for beginners determined during the training. CONCLUSIONS: Using a living animal model, a trainee has the opportunity to learn not only anastomotic techniques but also hemostatic control as well as overcoming mental strain during surgery. Living animal models are important in training because the fidelity of a living animal model is superior to nonliving models. Applying training using a half-ring model contributes to safe and efficient surgery.

もやもや病における脳表血管の幾何学的解析

小松克也, 三上毅, 秋山幸功, 江夏怜, 大川聡史, 鈴木比女, 鰐渕昌彦, 三國信啓

脳循環代謝 ( (一社)日本脳循環代謝学会 ) 30 ( 1 ) 107 - 107 2018年10月

Interdisciplinary Prevention and Management of Wound-Related Complications in Extracranial-to-Intracranial Bypass Surgery.

Rintaro Yokoyama, Takeshi Mikami, Ryo Ukai, Katsuya Komatsu, Yusuke Kimura, Hime Suzuki, Toshimi Honma, Toru Hirano, Tamotsu Saito, Ken Yamashita, Takatoshi Yotsuyanagi, Kiyohiro Houkin, Nobuhiro Mikuni

World neurosurgery 115 247 - 253 2018年07月 [査読有り] [国際誌]

Extracranial-to-intracranial (EC-IC) bypass surgery may be necessary in patients with moyamoya disease and other ischemic conditions. However, there is a potential risk of wound-related complications in some cases. In this study, we report our approach to the prevention of wound-related complications in EC-IC bypass. Technical considerations and pitfalls of surgery are also discussed. This study included 89 patients with ischemic-onset moyamoya disease and atherosclerotic disease who underwent 108 superficial temporal artery (STA)-to-middle cerebral artery bypass procedures. Our study emphasized 3 major features. First, 3-dimensional simulation imaging was used to confirm STA anatomy. Second, the STA was meticulously dissected on the epigaleal layer to protect the galeal layer. Third, scalp skin ischemia was taken into consideration at each step until skin closure. There was no neurologic morbidity or mortality in this series. There were 2 cases of major wound-related complications requiring plastic surgical intervention, and 4 cases of minor complications that were treated conservatively. In major complication cases, the scalp defect was treated with pedicle flap reconstruction. In EC-IC bypass surgery, interdisciplinary management involving neurosurgery, plastic surgery, and radiology should reduce wound-related complications and achieve safe surgery.

Development of moyamoya disease after non-herpetic acute limbic encephalitis: A case report.

Yasuhiro Takahashi, Takeshi Mikami, Hime Suzuki, Katsuya Komatsu, Daisuke Yamamoto, Shun Shimohama, Kiyohiro Houkin, Shintaro Sugita, Tadashi Hasegawa, Nobuhiro Mikuni

Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia 53 250 - 253 2018年07月 [査読有り] [国際誌]

We report a case of moyamoya disease (MMD), which developed after non-herpetic acute limbic encephalitis (NHALE) associated with anti-leucine-rich glioma-inactivated 1 (LGI1) antibody. The patient's mother had a history of MMD. No vascular lesions were identified at the time of the NHALE. Nine years later, the patient visited our hospital due to memory disturbances and repeated transient ischemic attacks affecting the right limb. Diffusion-weighted magnetic resonance imaging revealed scattered areas of signal hyperintensity, and the patient was ultimately diagnosed with MMD based on angiography. Revascularization surgery was performed on the left side, where cerebral blood flow was impaired on 123I-N-isopropyl-p-iodoamphetamine single photon emission computed tomography. Postoperatively, the patient was discharged with a normal neurological examination. NHALE associated with LGI1 antibodies is an autoimmune disease. Although autoimmune disease is the most frequent finding other than atherosclerosis in quasi-MMD, this is the first report of NHALE associated with anti-LGI1 antibodies mimicking quasi-MMD. Inflammation and angiogenesis may contribute to the development of MMD, in addition to genetic background.

Arterial Spin Labeling Method as a Supplemental Predictor to Distinguish Between High- and Low-Grade Gliomas.

Katsuya Komatsu, Masahiko Wanibuchi, Takeshi Mikami, Yukinori Akiyama, Satoshi Iihoshi, Kei Miyata, Toshiya Sugino, Kengo Suzuki, Aya Kanno, Shouhei Noshiro, Shunya Ohtaki, Nobuhiro Mikuni

World neurosurgery 114 e495-e500 2018年06月 [査読有り] [国際誌]

BACKGROUND: Preoperative evaluation of malignancy in gliomas is important for surgical planning, particularly to determine whether a 1,3-bis-2-chloroethyl-1-nitrosourea wafer should be placed into the tumor cavity. In some cases, the intraoperative pathologic diagnosis of World Health Organization grade differs from the final diagnosis. Supplemental methods in addition to the routine contrast tomography or magnetic resonance imaging sequences may provide a more accurate preoperative diagnosis. Because tumor vascularity has been useful in distinguishing between low- and high-grade gliomas, we evaluated the accuracy of the arterial spin labeling (ASL) method, which could measure the cerebral blood flow (CBF) without using contrast medium, to determine the malignancy of gliomas. METHODS: This study included 102 patients with glioma (grade II, n = 40; grade III, n = 18; grade IV, n = 44). All patients underwent ASL to determine the tumor blood flow (TBF) and CBF in the middle cerebral region. The relative tumor vascular index (tVI), which is calculated as TBF divided by CBF in the contralateral middle cerebral region, was used to avoid dispersion of the absolute TBF value. RESULTS: tVI was significantly greater (1.46 ± 0.751) in high-grade gliomas than in low-grade gliomas (1.05 ± 0.343) (P = 0.003). As for each grade, tVI was statistically higher in grade IV than in grade II (P = 0.03) gliomas. CONCLUSIONS: The noninvasive ASL method provides additional information to distinguish high-grade glioma from low-grade gliomas without using contrast medium.

Digital Polymerase Chain Reaction Quantification of SERPINA1 Predicts Prognosis in High-Grade Glioma.

Satoshi Ookawa, Masahiko Wanibuchi, Yuko Kataoka-Sasaki, Masanori Sasaki, Shinichi Oka, Shunya Ohtaki, Shouhei Noshiro, Katsuya Komatsu, Yukinori Akiyama, Takeshi Mikami, Nobuhiro Mikuni, Jeffery D Kocsis, Osamu Honmou

World neurosurgery ( Elsevier Inc. ) 111 e783-e789 - e789 2018年03月 [査読有り] [国際誌]

BACKGROUND: SERPINA1 plays an anti-inflammatory role in protecting tissues from proteolytic mechanisms. SERPINA1 is positive in gliomas by immunohistochemical analysis; however, the role of SERPINA1, including the relationship with prognosis, has been uncertain. In recent years, digital polymerase chain reaction (PCR) has provided ultra-sensitive assessment of messenger RNA expression from formalin-fixed paraffin-embedded (FFPE) tissues. OBJECTIVE: In this study, we quantitatively determined the expression of SERPINA1 in high-grade gliomas (HGGs) using digital PCR, and we analyzed its relationship with prognosis. METHODS: Twenty-nine FFPE surgical samples from patients with HGGs (7 of World Health Organization [WHO] grade III and 22 of WHO grade IV), and human glioblastoma cell lines, U87 and U118, were used for analysis. A qualitative assessment using immunostaining and quantitative assessment using digital PCR were performed to assess the expression of SERPINA1. RESULTS: The expression of SERPINA1 was demonstrated in glioma tissues and glioblastoma multiforme cell lines by immunostaining. Digital PCR analysis showed that SERPINA1 was expressed in 14.3% and 63.6% of the tissues from patients with grade III and grade IV HGG, respectively (P = 0.035). The median overall survival of 38.8 months in the low SERPINA1 expression group was longer than that of 15.3 months in the high expression group (P = 0.030). CONCLUSIONS: The frequency and the amount of SERPINA1 expression were higher in grade IV than in grade III HGGs. The high expression of SERPINA1 indicates a poor prognosis of HGGs.

Effectiveness of the 3D Monitor System for Medical Education During Neurosurgical Operation.

Masahiko Wanibuchi, Katsuya Komatsu, Yukinori Akiyama, Takeshi Mikami, Nobuhiro Mikuni

World neurosurgery ( Elsevier {BV} ) 109 e105-e109 - e109 2018年01月 [査読有り] [国際誌]

BACKGROUND: Three-dimensional (3D) graphics are used in the medical field, especially during surgery. Although 3D monitoring is useful for medical education, its effectiveness needs to be objectively evaluated. The aim of this study was to investigate the efficacy of 3D monitoring in the surgical education of medical students. METHODS: A questionnaire on high-definition 3D monitoring was given to fifth-year medical students in a 6-year program. Sixty-four students wore polarized glasses and observed a microsurgical operation through a 3D monitor. The questionnaire contained questions on stereopsis, neurosurgical interest, visual impact, comprehension of surgical anatomy and procedures, optical sharpness, active learning enhancement, and eye exhaustion. These parameters were evaluated on a 5-point scale that spanned negative and positive scores. RESULTS: The average score of each parameter ranged from 3.13 to 3.78, except for eye exhaustion, which was 0.88. The items for which the students reported positive perceptions (scores of 4 or 5) were stereopsis (67.2% of students), neurosurgical interest (62.5%), visual impact and optical sharpness (60.9% for both), active learning enhancement (57.8%), and comprehension of surgical anatomy (50.0%) and procedures (42.2%). By contrast, only eye exhaustion was evaluated negatively (26.6%). CONCLUSION: The use of 3D monitoring systems in medical education offers the advantage of stereopsis and contributes to surgical training. However, improvements are required to decrease eye exhaustion.

Electrophysiological influence of temporal occlusion of the parent artery during aneurysm surgery.

Katsuya Komatsu, Takeshi Mikami, Rintaro Yokoyama, Yuto Suzuki, Shoichi Komura, Rei Enatsu, Shouhei Noshiro, Kei Miyata, Yukinori Akiyama, Nobuhiro Mikuni

Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia ( ELSEVIER SCI LTD ) 45 199 - 204 2017年11月 [査読有り] [国際誌]

Intraoperative monitoring of the motor evoked potential (MEP) during cerebral aneurysm surgery has been widely used to confirm surgical safety. In this study, we retrospectively analyzed the influence of the MEP amplitude resulting from temporal occlusion of the parent artery, and appropriate judgement in the surgery was discussed. Ten patients underwent temporal occlusion of the parent artery during aneurysm surgery, and five of these patients showed a decrease in the MEP amplitude following temporal arterial occlusion. Clinical factors in patients with and without MEP decrease were compared. The time gap between the surgical procedure and the MEP change and recovery was then investigated. A decrease in the MEP amplitude caused by temporal occlusion had a significantly higher occurrence compared with permanent clip failure. The time from the release procedure to MEP amplitude recovery was relatively longer than the time from the occlusion procedure to the decrease in MEP amplitude. The time from release procedure to MEP amplitude recovery showed a weak correlation with the parent artery occlusion time. There is a time gap between releasing the temporal arterial occlusion and MEP recovery that is similar to temporal parent arterial occlusion and the MEP decrease. The cause of MEP amplitude should be judged carefully, and influence of parent artery temporal occlusion should be taken into consideration during aneurysm clipping.

Geometrical Complexity of Cortical Microvascularization in Moyamoya Disease.

Katsuya Komatsu, Takeshi Mikami, Hime Suzuki, Yukinori Akiyama, Rei Enatsu, Masahiko Wanibuchi, Nobuhiro Mikuni

World neurosurgery ( Elsevier {BV} ) 106 51 - 59 2017年10月 [査読有り] [国際誌]

BACKGROUND: Dilatation of the microvascular diameter is recognized in moyamoya disease and referred to as microvascularization. The purpose of this study was to characterize the cortical microvascularization in moyamoya disease using imaging analysis, and to explore the developmental mechanism of the collateral network around the cortical surface. METHODS: A total of 20 hemispheric sides of 14 patients with moyamoya disease were included in this study. From the intraoperative images, cortical surface images were extracted, and binary images were subsequently created. Then the ratio of the microvessels of the brain surface (vascular fraction; VF) and the box-counting fractal dimension (Db) values were calculated. The VF and Db values in the moyamoya disease group were then compared with those in atherosclerotic disease and nonischemic disease groups, and assessed in terms of clinical and radiologic factors. RESULTS: VF was significantly higher in the moyamoya disease group compared with the atherosclerotic disease group, and Db was significantly higher in the moyamoya disease group compared with the atherosclerotic disease and nonischemic disease groups. In the moyamoya disease group, VF showed a moderate correlation with magnetic resonance angiography (MRA) score. Moreover, Db was significantly higher in the pediatric patients, in the presence of ischemic symptoms, and in the presence of ivy sign, and Db showed a moderate correlation with MRA score and cerebral blood flow in moyamoya disease. CONCLUSIONS: In the patients with moyamoya disease, the cortical microvascularization exhibited increased Db and dilatation of the pial arteries. In moyamoya disease, cortical microvascularization is associated with clinical and radiologic factors. This microvascularization might be a compensatory mechanism in the ischemic condition in moyamoya disease.

Intraoperative Mapping and Monitoring of the Pyramidal Tract Using Endoscopic Depth Electrodes.

Yukinori Akiyama, Shunya Ohtaki, Katsuya Komatsu, Kentaro Toyama, Rei Enatsu, Takeshi Mikami, Masahiko Wanibuchi, Nobuhiro Mikuni

World neurosurgery ( ELSEVIER SCIENCE INC ) 105 14 - 19 2017年09月 [査読有り] [国際誌]

OBJECTIVE: To evaluate motor function during neuroendoscopic resectioning of deep-seated brain tumors using endoscopically guided depth electrodes. METHODS: For 12 cases of thalamic tumors, including high-grade gliomas, germinomas, and malignant lymphomas, depth electrodes were inserted using endoscopic guides between the tumor and the pyramidal tract in the thalamus. Motor-evoked potentials (MEPs) were continuously recorded during neuroendoscopic resectioning of the tumors. RESULTS: Monitoring of MEP responses using depth electrodes in all 12 cases was successful. The minimum stimulus intensity threshold required to induce MEP responses was 3 mA. Gross total or subtotal resections were successful with this technique for all patients with glioma. No additional neurologic impairments were found after surgery in any of the cases. CONCLUSIONS: Continuous MEP measurement using depth electrodes can serve as a new monitoring technique for endoscopic resectioning of deep-seated brain tumors.

Prevalence of and risk factors for enlarged perivascular spaces in adult patients with moyamoya disease.

Tomoyoshi Kuribara, Takeshi Mikami, Katsuya Komatsu, Hime Suzuki, Hirofumi Ohnishi, Kiyohiro Houkin, Nobuhiro Mikuni

BMC neurology ( BIOMED CENTRAL LTD ) 17 ( 1 ) 149 - 149 2017年08月 [査読有り] [国際誌]

BACKGROUND: Enlarged perivascular spaces (EPVS) are often observed with magnetic resonance imaging in patients with small vessel disease. However, the risk factors, radiological features, and clinical relevance of EPVS in patients with moyamoya disease are poorly understood. The purpose of this study was to evaluate EPVS, the risk factors of many EPVS, and the pathophysiology of EPVS in adult patients with moyamoya disease. METHODS: One hundred cerebral hemispheres of 50 adult patients with moyamoya disease were examined. The control group consisted of 50 age/sex-matched patients without ischemic disease. The numbers of EPVS at the level of the centrum semiovale per hemisphere were compared between the moyamoya disease and control groups. In each hemisphere, the total numbers of EPVS were categorized into five grades (0-4), and the clinical and radiological characteristics of the predictive factors in patients in the high EPVS grade group (EPVS grade = 4) were assessed. RESULTS: The EPVS counts and grades were significantly higher in the moyamoya disease group. Analyses of the background characteristics of the patients with moyamoya disease revealed that significantly higher prevalence of high EPVS grades were associated with the female sex, hypertension, high magnetic resonance angiography scores, high numbers of flow voids in the basal ganglia, high brain atrophy scores, ivy signs, and white matter lesions. A logistic multivariate analysis of the patients with high EPVS grades revealed significant associations with the female sex, hypertension, and flow voids in the basal ganglia. CONCLUSIONS: Increased EPVS were confirmed in adult patients with moyamoya disease, and the associated clinical and radiological factors were identified. The presence of hypertension, the female sex, and flow voids in the basal ganglia were important for predicting high EPVS grades in patients with moyamoya disease. Reductions in arterial pulsations with steno-occlusive changes can inhibit the flow of interstitial fluid, which can increase the number of EPVS in patients with moyamoya disease. Other clinical factors, such as the female sex and hypertension, may promote secondary brain damage in patients with moyamoya disease. Further evaluations of EPVS in patients with moyamoya disease are needed to better understand their pathophysiological importance.

Meandering flow void around the splenium in moyamoya disease.

Takeshi Mikami, Tomoyoshi Kuribara, Katsuya Komatsu, Yusuke Kimura, Masahiko Wanibuchi, Kiyohiro Houkin, Nobuhiro Mikuni

Neurological research ( TAYLOR & FRANCIS LTD ) 39 ( 8 ) 702 - 708 2017年08月 [査読有り] [国際誌]

OBJECTIVES: Meandering flow void around the splenium, which can be recognized on conventional T2-weighted images, implicates collateral flow in the splenial artery in patients with moyamoya disease. In this report, curves of flow voids around the splenium (SFVs) were evaluated in patients with moyamoya disease, and their diagnostic value and pathophysiology were verified. METHODS: A total of 65 consecutive patients with moyamoya disease were included in this analysis. The number of SFV curves was counted on each side. The numbers of SFV curves in patients with moyamoya disease was compared with those in the control group. The clinical features of patients with large numbers of flow voids were analyzed. RESULTS: The mean number of SFVs was significantly higher in the moyamoya disease group than in the control group or the atherosclerotic disease group. The cut-off SFV count for a diagnosis of moyamoya disease should be set to 2.25 in consideration of receiver operating characteristic curve analysis. A multivariate logistic analysis of SFV data in moyamoya disease revealed significant differences between the high SFV count group (≥2.25) and the low SFV count group (<2.25) in age, flow voids in the basal ganglia, and magnetic resonance angiography score of the internal carotid artery and anterior cerebral artery. CONCLUSION: Based on this study, number of SFV curves on conventional T2-weighted imaging could be a useful measurement for confirming a diagnosis of moyamoya disease. Increased number of SFV curves was associated with age and progress of disease.

Complementary Relation Between Direct and Indirect Bypass in Progress of Collateral Circulation in Moyamoya Disease.

Shoichi Komura, Takeshi Mikami, Toshiya Sugino, Yuto Suzuki, Katsuya Komatsu, Masahiko Wanibuchi, Nobuhiro Mikuni

World neurosurgery ( ELSEVIER SCIENCE INC ) 104 197 - 204 2017年08月 [査読有り] [国際誌]

BACKGROUND: One of the important aims of surgery for moyamoya disease is to establish indirect revascularization. The purpose of this study was to assess the progress of the middle meningeal artery (MMA) after our novel preservation method and to evaluate the relation between direct and indirect bypass in the chronic stage. METHODS: A total of 24 hemispheric sides of 19 patients with moyamoya disease were included in this study. Craniotomy was performed with preservation of the MMA during the procedure, then direct bypass was carried out. The relationship between anatomic variations of the MMA and success rate of preserving the MMA during craniotomy was noted. The alteration of the MMA and superficial temporal artery (STA) diameters was then evaluated using magnetic resonance imaging, and the correlation between the MMA and the STA in the chronic stage was examined. RESULTS: In total, the MMA was preserved during craniotomy in 20 hemispheric sides (83.3%). During the 3-year follow-up period, the MMA and STA diameters were significantly increased. At 3 years after surgery, the alteration of the MMA diameter was significantly more marked in pediatric cases than in adult cases, and MMA diameter was moderately but significantly negatively correlated with STA diameter. CONCLUSIONS: In moyamoya disease, the MMA could be developed as a pathway for indirect revascularization even after simple preservation, especially in pediatric patients. The progress of the MMA and the STA occurs through their synergistic interaction, and the balance might be decided based on their complementary relations in the chronic stage.

Exposure of titanium implants after cranioplasty: A matter of long-term consequences

Takeshi Mikami, Kei Miyata, Katsuya Komatsu, Ken Yamashita, Masahiko Wanibuchi, Nobuhiro Mikuni

Interdisciplinary Neurosurgery ( Elsevier {BV} ) 8 64 - 67 2017年06月 [査読有り]

Although the use of titanium implants in cranioplasty has recently become common, long-term results of this strategy are sometimes difficult to manage. The aim of this study was to clarify the characteristics of patients developing exposure of titanium implants. Records of eight patients with exposure of titanium implants were reviewed. Patient ages ranged from 41 to 77 (mean, 56.8) years. Two patients were male, and six were female. The periods from implantation to exposure of titanium implants ranged from 5 to 87 (mean, 30.5) months. In seven cases, titanium mesh cranioplasty was performed after postcraniotomy infections. The titanium implants were removed in all cases. Scalp tissue was closed by applying a primary closure technique in five cases, though scalp reconstruction was performed with a rotation flap in the other three cases involving large scalp ulceration. Although the use of titanium implants is convenient, the indications should be carefully considered, especially in cases with postoperative surgical site infections and in patients with thin scalp skin. For these patients, long-term follow up is necessary.

Pathophysiological consideration of medullary streaks on FLAIR imaging in pediatric moyamoya disease.

Hime Suzuki, Takeshi Mikami, Tomoyoshi Kuribara, Kazuhisa Yoshifuji, Katsuya Komatsu, Yukinori Akiyama, Hirofumi Ohnishi, Kiyohiro Houkin, Nobuhiro Mikuni

Journal of neurosurgery. Pediatrics ( AMER ASSOC NEUROLOGICAL SURGEONS ) 19 ( 5 ) 560 - 566 2017年05月 [査読有り] [国際誌]

OBJECTIVE Medullary streaks detected on fluid-attenuated inversion recovery (FLAIR) imaging have been considered to be reflected ischemic regions in pediatric moyamoya disease. The purpose of this study was to evaluate these medullary streaks both clinically and radiologically and to discuss associated pathophysiological concerns. METHODS The authors retrospectively reviewed data from 14 consecutive pediatric patients with moyamoya disease treated between April 2009 and June 2016. Clinical and radiological features and postoperative imaging changes were analyzed. In 4 patients, hyperintense medullary streaks on FLAIR imaging (HMSF) at the level of the centrum semiovale were detected. RESULTS The HMSF were coincident with hyperintense medullary streaks on a T2-weighted image, though they were not completely coincident with the vasculature on either a T2*-weighted image or contrast-enhanced CT. Analysis revealed significantly higher values in terms of MR angiography scores, number of flow voids of the basal ganglia, and the presence of the medullary artery in the group with HMSF than in those without. In contrast, the presence of white matter damage was significantly less frequent in the HMSF group. All HMSF disappeared after surgery, and the mean apparent diffusion coefficient at the same level was significantly reduced postoperatively. CONCLUSIONS Although HMSF should be associated with collateral circulation in moyamoya disease, other factors may be involved, including stagnated cerebrospinal fluid or vasogenic edema that is relevant to the impaired state of the white matter. Findings in this study provide insight into the pathophysiological basis of the perivascular space in moyamoya disease.

Assessment of the cortical artery using computed tomography angiography for bypass surgery in moyamoya disease.

Hime Suzuki, Takeshi Mikami, Katsuya Komatsu, Shouhei Noshiro, Kei Miyata, Toru Hirano, Masahiko Wanibuchi, Nobuhiro Mikuni

Neurosurgical review ( SPRINGER ) 40 ( 2 ) 299 - 307 2017年04月 [査読有り] [国際誌]

Computed tomography angiography (CTA) is often used to assess the vascular status in moyamoya disease. The purpose of the study is to identify the characteristics of cortical arteries (M4) of moyamoya disease on CTA; the clinical significance of which is also discussed. A total of 38 hemispheric sides of 27 patients with moyamoya disease were included in this study. The number of M4 was visualized on CTA using cortical surface imaging and compared between the moyamoya disease group and the non-moyamoya disease group or the control group. Then, the clinical and radiological factors associated with the number of M4, the distribution of M4, and collateral circulation were examined. The number of M4 was lower in the moyamoya disease group than in the non-moyamoya disease group and in the control group (p < 0.05). There are few predictive clinical factors of the number of M4 except male sex. The prefrontal artery, precentral artery, central artery, and angular artery had a significantly higher prevalence in moyamoya disease (p < 0.05). The durocortical and periventricular anastomosis had a significantly higher prevalence in moyamoya disease (p < 0.05). The prevalence and distribution pattern of cortical arteries in moyamoya disease differed from that of the non-moyamoya disease group, and the distribution patterns of M4 might be influenced by collateral circulation. It is thus essential to recognize M4 to assess the recipient artery so as to ensure superficial temporal artery-middle cerebral artery bypass.

Endovascular Therapy for a Post-irradiated Cervical Pseudoaneurysm at the Carotid Stump: A Case Report.

Masayasu Arihara, Kei Miyata, Satoshi Iihoshi, Hiroyuki Yamaguchi, Kentaro Toyama, Katsuya Komatsu, Atsumu Hashimoto, Masahiko Wanibuchi, Nobuhiro Mikuni

NMC case report journal 4 ( 2 ) 59 - 62 2017年04月 [査読有り] [国内誌]

A nearly 80-year-old man with a history of radiotherapy (RT) and total laryngectomy for laryngeal cancer 25 years previously presented with a rapidly growing mass on the right side of his neck. A huge pseudoaneurysm (pseudoAN) was detected at the right carotid bifurcation, though angiography performed four years previously had shown total occlusion of the internal carotid artery. Stent-assisted coil embolization enabled aneurysm sac shrinkage. Clinicians must be aware that the stump of an arterial occlusion associated with RT can change into a pseudoAN over the long term and must provide follow-up in such cases.

Assessment of Hemodynamic Compromise Using Computed Tomography Perfusion in Combination with 123I-IMP Single-Photon Emission Computed Tomography without Acetazolamide Challenge Test.

Atsumu Hashimoto, Takeshi Mikami, Katsuya Komatsu, Shouhei Noshiro, Tohru Hirano, Masahiko Wanibuchi, Nobuhiro Mikuni

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( Elsevier {BV} ) 26 ( 3 ) 627 - 635 2017年03月 [査読有り] [国際誌]

OBJECTIVES: The acetazolamide challenge test in conjunction with 123I-IMP single-photon emission computed tomography (SPECT) is a known method of assessing cerebrovascular reserve capacity. In this study, we investigated whether CT perfusion in combination with resting state 123I-IMP SPECT could be used instead of the acetazolamide challenge test to evaluate hemodynamic compromise in patients with atherosclerotic occlusive disease. METHODS: Twenty consecutive patients with unilateral internal carotid artery or middle cerebral artery steno-occlusive disease were enrolled. 123I-IMP SPECT was performed with and without the acetazolamide challenge test, and with CT perfusion. Cerebral blood flow (CBF), cerebral blood volume, and mean transit time (MTT) obtained by CT perfusion were compared with CBF and cerebrovascular reactivity (CVR) obtained by 123I-IMP SPECT. RESULTS: The asymmetry ratio of MTT as measured by CT perfusion showed a strong correlation with the CVR to acetazolamide as measured by 123I-IMP SPECT (ρ = -.780, P <.001). Based on the CBF obtained through 123I-IMP SPECT and the MTT obtained through CT perfusion, hemodynamic compromise was detected with high sensitivity (1.000) and specificity (.929), and a cutoff value of 30% was found to be suitable for the asymmetry ratio of MTT. MTT prolongation was significantly improved after revascularization surgery in hemodynamic compromise (P = .028). CONCLUSION: MTT as measured by CT perfusion in combination with CBF as measured by resting state 123I-IMP SPECT may be useful for evaluating hemodynamic compromise as an alternative to the acetazolamide challenge test.

[Bone Flap Resorption after Cranioplasty in Pediatric Patients:Report of 2 Cases].

Rintaro Yokoyama, Takeshi Mikami, Shouhei Noshiro, Kei Miyata, Kentaro Toyama, Katsuya Komatsu, Noriaki Kikuchi, Tadashi Hasegawa, Nobuhiro Mikuni

No shinkei geka. Neurological surgery 45 ( 1 ) 47 - 52 2017年01月 [査読有り] [国内誌]

Aseptic bone flap resorption, a rare complication after cranioplasty following decompressive craniectomy, is more likely to develop in children. We experienced two cases of aseptic bone flap resorption and identified potential pathophysiological mechanisms through histological findings. In the first case, an 11-year-old girl underwent decompressive craniectomy due to brain swelling with contusion. An autologous bone flap was cryopreserved for four months. Twenty-five months after cranioplasty with autologous bone flap, aseptic bone flap resorption was observed, and cranioplasty was performed with ceramic bone. Most of the histological findings in this case showed mature osseous tissue, while some showed osteoclasts and new bone formation due to endochondral ossification. In the second case, a 10-year-old girl underwent frontal craniectomy and removal of contusional hematoma. Fourteen months after cranioplasty with autologous bone flap, aseptic bone flap resorption was observed, and cranioplasty was performed with ceramic bone paste. The progression of bone flap resorption was not recognized for 12 months. In these cases, new bone formation was not necessarily linked to pathological bone flap resorption. It is supposed that the balance between bone destruction and new bone formation was disrupted by unknown factors.

[Pediatric Iatrogenic Vertebral Arteriovenous Fistula Successfully Treated with Endovascular Treatment:A Case Report].

Rintaro Yokoyama, Satoshi Iihoshi, Kei Miyata, Kentaro Toyama, Katsuya Komatsu, Masahiko Wanibuchi, Nobuhiro Mikuni

No shinkei geka. Neurological surgery ( Igaku-Shoin Ltd ) 44 ( 10 ) 857 - 861 2016年10月 [査読有り] [国内誌]

OBJECT: We report a relatively rare case of pediatric iatrogenic extradural vertebral arteriovenous fistula. CASE: A five-year-old boy with a history of multiple surgeries for Total Anomalous Pulmonary Venous Return(TAPVR)exhibited vascular engorgement of his right neck from about 4 years old. We thought that this was caused by his past operations. He demonstrated swollen blood vessels in the right neck and pulmonary hypertension with increased right heart load. A right extradural vertebral arteriovenous fistula was seen on angiography. A high flow shunt was present at the V1 segment, at the level of the sixth cervical vertebra, and a 12 mm venous pouch was present anterior to the vertebral artery. We recognized the outlet passages of the cranial tract were the vertebral venous plexus, internal jugular vein, and right atrium. We performed endovascular transarterial embolization using a hydrogel coil. As a result, we treated with a high volume embolization ratio. Following treatment, the arteriovenous fistula disappeared while anterograde blood flow of the vertebral artery was preserved. The patient demonstrated no neurological deficits, improved right heart load, and his venous pouch of the neck. He has had no recurrence in the two years after treatment. CONCLUSION: Endovascular surgery is effective and safe for the treatment of iatrogenic vertebral arteriovenous fistula.

Erdheim-Chester Disease Involving the Central Nervous System with the Unique Appearance of a Coated Vertebral Artery.

Hime Suzuki, Masahiko Wanibuchi, Katsuya Komatsu, Yukinori Akiyama, Takeshi Mikami, Shintaro Sugita, Tadashi Hasegawa, Mitsunori Kaya, Kohichi Takada, Nobuhiro Mikuni

NMC case report journal 3 ( 4 ) 125 - 128 2016年10月 [査読有り] [国内誌]

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis. It is characterized by multiple xanthogranulomatous masses throughout the body, predominantly in the tibia. One of the characteristic radiological findings of the lesions associated with ECD is a "coated artery," which is often observed in the aorta. Although approximately one-fourth of ECD cases involve the central nervous system (CNS), an intracranial-coated artery has only been reported in four cases. We report a case of ECD that involves the CNS and has the unique appearance of a coated vertebral artery (VA). These tumors entirely encase the bilateral VAs without stenosis and are attached to the dura. Cranial magnetic resonance imaging also showed multiple extra-axial tumors in the cavernous sinus, the frontal convexity, and the orbital cavity. Further investigation revealed additional extracranial lesions around the cervical carotid artery, at the bilateral tibia, and at the elbow joint. A biopsy of the cervical and tibial lesions confirmed ECD. Steroid therapy resulted in a month-long improvement of preoperative symptoms. However, the patient's condition gradually progressed and he died of pneumonia 1 year after ECD diagnosis. The encasement of the intracranial artery by the tumor without stenosis and the dural attachment suggest ECD, which requires whole body investigation.

Quantitative Assessment of Flow Reduction After Feeder Embolization in Meningioma by Using Pseudocontinuous Arterial Spin Labeling.

Masahiko Wanibuchi, Katsuya Komatsu, Yukinori Akiyama, Takeshi Mikami, Satoshi Iihoshi, Kei Miyata, Nobuhiro Mikuni

World neurosurgery ( ELSEVIER SCIENCE INC ) 93 237 - 45 2016年09月 [査読有り] [国際誌]

BACKGROUND: Meningioma is a hypervascular tumor of the central nervous system. Angiographic disappearance of tumor blush after preoperative feeder embolization allows qualitative, but not quantitative, assessment of flow reduction. Pseudocontinuous arterial spin labeling (PCASL), which has evolved from magnetic resonance imaging techniques, allows noninvasive measurement of cerebral blood flow (CBF) using water protons in the arterial blood flow. OBJECTIVE: We applied PCASL for assessment of blood flow in meningioma and its reduction on preoperative embolization. METHODS: Forty-one consecutive patients (11 males, 30 females) with histologically proven meningioma were evaluated by PCASL. Quantitative assessment by an absolute value of tumor blood flow (TBF) and a relative value of tumor vascular index (tVI; calculated as TBF divided by CBF) were calculated. In 8 cases, in which preoperative embolization was achieved, flow reduction rate was evaluated. RESULTS: TBF of meningiomas, 155.8 mL/100 g·min(-1) on average, was 2.6 times higher than CBF, 59.9 mL/100 g·min(-1) (P < 0.001). Patients who underwent feeder embolization showed statistically greater flow reduction rate, which was calculated as 42.7% (P < 0.05). Mean tVI before embolization was 4.1, which was reduced to 2.1 after embolization. CONCLUSION: PCASL could yield quantitative assessment of blood flow in meningioma including flow reduction rate in cases of feeder embolization.

Neuromodulatory Role of Revascularization Surgery in Moyamoya Disease.

Shouhei Noshiro, Takeshi Mikami, Katsuya Komatsu, Aya Kanno, Rei Enatsu, Shogo Yazawa, Takashi Nagamine, Masao Matsuhashi, Nobuhiro Mikuni

World neurosurgery ( Elsevier {BV} ) 91 473 - 82 2016年07月 [査読有り] [国際誌]

BACKGROUND: To evaluate the effectiveness of bypass surgery for moyamoya disease, electrocorticography was first evaluated. METHODS: A total of 13 hemispheres in 9 patients with moyamoya disease were included in this study. To record the spectral power of electrocorticography continuously during the bypass procedure, a 4 × 5 subdural electrode grid was placed on the middle frontal gyrus. The changes in spectral power before and after bypass surgery were evaluated and compared with those in a control group. The correlation between changes in spectral power and regional cerebral blood flow was analyzed. RESULTS: The average spectral power ratio of the beta band per total band in moyamoya disease before bypass surgery was lower than that of controls (P = 0.027), and the significance disappeared after bypass surgery (P = 0.800). The spectral power levels of the beta band and gamma band were increased in moyamoya disease after bypass surgery (P < 0.001). Changes in spectral power of the beta band correlated with changes in regional cerebral blood flow (P = 0.002). CONCLUSIONS: The spectral power of the beta band on electrocorticography was focally suppressed in patients with moyamoya disease, and the suppression was reversible by revascularization surgery. Steno-occlusive ischemic changes in moyamoya disease might cause suppression of neurophysiologic activity, and the present results provide insight into the potential neuromodulatory role of revascularization surgery.

Training for Skull Base Surgery with a Colored Temporal Bone Model Created by Three-Dimensional Printing Technology

Masahiko Wanibuchi, Shouhei Noshiro, Toshiya Sugino, Yukinori Akiyama, Takeshi Mikami, Satoshi Iihoshi, Kei Miyata, Katsuya Komatsu, Nobuhiro Mikuni

World Neurosurgery ( Elsevier {BV} ) 91 66 - 72 2016年07月 [査読有り] [国際誌]

OBJECTIVE: A 3-dimensional temporal bone model for skull base surgical training was reconstructed via the use of a selective laser sintering technique, which is one of the 3-dimensional printing technologies. METHODS: The temporal bone model was created in 2 pieces to remove powder material in the mastoid air cells and to place dye into the semicircular canal and the Fallopian canal. RESULTS: The powder material was minimal, and the decisive structures were identified in color. CONCLUSIONS: This artificial model will pave the way to a "new era" in surgical training and medical education.

Intraoperative Mapping and Monitoring for Rootlets of the Lower Cranial Nerves Related to Vocal Cord Movement.

Masahiko Wanibuchi, Yukinori Akiyama, Takeshi Mikami, Katsuya Komatsu, Toshiya Sugino, Kengo Suzuki, Aya Kanno, Shunya Ohtaki, Shouhei Noshiro, Nobuhiro Mikuni

Neurosurgery ( OXFORD UNIV PRESS INC ) 78 ( 6 ) 829 - 34 2016年06月 [査読有り] [国際誌]

BACKGROUND: Damage to the motor division of the lower cranial nerves that run into the jugular foramen leads to hoarseness, dysphagia, and the risk of aspiration pneumonia; therefore, its functional preservation during surgical procedures is important. Intraoperative mapping and monitoring of the motor rootlets at the cerebellomedullary cistern using endotracheal tube electrodes is a safe and effective procedure to prevent its injury. OBJECTIVE: To study the location of the somatic and autonomic motor fibers of the lower cranial nerves related to vocal cord movement. METHODS: Twenty-four patients with pathologies at the cerebellopontine lesion were studied. General anesthesia was maintained with fentanyl and propofol. A monopolar stimulator was used at amplitudes of 0.05 to 0.1 mA. Both acoustic and visual signals were displayed as vocalis muscle electromyographic activity using endotracheal tube surface electrodes. RESULTS: The average number of rootlets was 7.4 (range, 5-10); 75% of patients had 7 or 8 rootlets. As many as 6 rootlets (2-4 in most cases) were responsive in each patient. In 23 of the 24 patients, the responding rootlets congregated on the caudal side. The maximum electromyographic response was predominantly in the most caudal or second most caudal rootlet in 79%. CONCLUSION: The majority of motor fibers of the lower cranial nerves run through the caudal part of the rootlets at the cerebellomedullary cistern, and the maximal electromyographic response was elicited at the most caudal or second most caudal rootlet. ABBREVIATION: EMG, electromyographic.

Reversibility of White Matter Hyperintensity by Revascularization Surgery in Moyamoya Disease.

Katsuya Komatsu, Takeshi Mikami, Shouhei Noshiro, Kei Miyata, Masahiko Wanibuchi, Nobuhiro Mikuni

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( Elsevier {BV} ) 25 ( 6 ) 1495 - 502 2016年06月 [査読有り] [国際誌]

BACKGROUND: White matter lesions (WMLs) indicate progressive cerebral small vessel disease and are frequently observed in aging people and stroke patients. The purpose of this study was to evaluate WMLs and the influence of revascularization surgery for WMLs in patients with moyamoya disease. METHODS: A total of 42 hemispheres in 21 patients with moyamoya disease were included in this analysis. WMLs were detected on fluid-attenuated inversion recovery (FLAIR) imaging in 24 hemispheres. The distribution pattern of WMLs was categorized. WMLs were measured by manually creating a region of interest, and the total WML volume in the hemisphere was estimated and compared with the control group. Clinical features of patients with WMLs and postoperative changes were analyzed. RESULTS: The total WML volume in moyamoya disease was significantly higher than that of controls (P = .014). WMLs were observed in the internal watershed zone, especially in the watershed zone between the anterior cerebral artery and the middle cerebral artery. Patients with WMLs had significantly higher magnetic resonance angiography scores compared with controls (P = .015). A given patient's total WML volume per hemisphere was significantly decreased after surgery (P = .001). CONCLUSIONS: WMLs on FLAIR imaging increase in patients with moyamoya disease and are reversible by revascularization surgery. Improvement of cerebral blood flow is partly related to the decrease in WMLs. The present results provide insight into the potential role of revascularization surgery.

Cortical and subcortical vascular hypointensity on T2* weighted imaging in moyamoya disease.

Shouhei Noshiro, Takeshi Mikami, Katsuya Komatsu, Kei Miyata, Yukinori Akiyama, Masahiko Wanibuchi, Nobuhiro Mikuni

Neurological research ( TAYLOR & FRANCIS LTD ) 38 ( 2 ) 110 - 6 2016年02月 [査読有り] [国際誌]

OBJECTIVES: Decreased cortical and subcortical vascular signals in gradient echo T2* weighted imaging have been reported in acute stroke due to major artery occlusion. The purpose of this study was to evaluate this cortical and subcortical vascular hypointensity (CSVH) in patients with moyamoya disease. METHODS: Subjects were 20 consecutive patients with moyamoya disease. The numbers of CSVH in each hemisphere were counted and the numbers were compared between patients with moyamoya disease and controls. The distribution of CSVH, clinical features of cases exhibiting large numbers of CSVH and post-operative changes were analysed. RESULTS: Patients with moyamoya disease had significantly more CSVH in the middle cerebral artery territory (p < 0.001) and the anterior cerebral artery territory (p < 0.001) compared with controls. The number of CSVH was correlated significantly with regional cerebral blood flow, as shown through simple regression analysis (R = 0.461, p = 0.006), and the numbers of CSVH were significantly higher in patients with higher magnetic resonance angiography scores (p = 0.017). A given patient's total number of CSVH per hemisphere was significantly decreased after surgery (p = 0.018). CONCLUSION: CSVH on T2* WI may be a useful tool for diagnosing and evaluating the extent of moyamoya disease. Our small series study shows that revascularization surgery can decrease the number of CSVH.

Transfemoral Carotid Artery Stenting Using Proximal Balloon Protection for Patients with Severe Elongation of the Aortic Arch: Inner-catheter Exchange with the Balloon Guide Catheter Anchored ("BGA Exchange")

Miyata Kei, Iihoshi Satoshi, Yokoyama Rintaro, Toyama Kentaro, Komatsu Katsuya, Wanibuchi Masahiko, Mikuni Nobuhiro

脳神経血管内治療 ( 特定非営利活動法人日本脳神経血管内治療学会 ) 10 ( 4 ) 225 - 230 2016年

Objective: Anatomical factors such as aortic arch elongation or angulation in elderly patients with arteriosclerotic change often make it difficult to perform carotid artery stenting (CAS) via the transfemoral approach under proximal balloon protection (PBP). We report a novel technique of transfemoral CAS using the inner catheter exchange method for a patient with a type III aortic arch.

Case Presentations: A 78-year-old man presented with symptomatic left carotid artery stenosis. A balloon guide catheter (BGC) was needed for PBP via the transfemoral approach. Initially, the modified Simmons-shaped inner catheter could not follow the half-stiff long guidewire to the external carotid artery (ECA) by the co-axial method. Accordingly, the inner catheter was safely exchanged with a flexible JB2 catheter with the balloon of the BGC fully inflated on the way to the left common carotid artery (CCA). Following the half-stiff long guidewire and with the JB2 catheter advanced into the distal portion of the left ECA beforehand, the BGC was successfully navigated into the left CCA below the bifurcation. Further procedures were performed without any complications.

Conclusion: This technique might be useful in patients with high risk of distal thromboembolic complications in transfemoral CAS with severe elongation of the aortic arch.

Vascular remodeling of the circle of Willis in moyamoya disease.

Takeshi Mikami, Shouhei Noshiro, Katsuya Komatsu, Kei Miyata, Yukinori Akiyama, Masahiko Wanibuchi, Nobuhiro Mikuni

Neurological research ( MANEY PUBLISHING ) 37 ( 10 ) 880 - 5 2015年10月 [査読有り] [国際誌]

OBJECTIVES: A positive (outward) remodelling pattern in patients with typical atherosclerotic disease was recognised using magnetic resonance imaging (MRI). In this report, the outer diameter of the circle of Willis was evaluated in patients with moyamoya disease, and its remodelling pattern was verified. METHODS: A total of 18 consecutive patients with moyamoya disease were included in this analysis. The diameter of the terminal portion of the internal carotid artery (ICA) (C1), proximal portion of the middle cerebral artery (MCA) (M1) and proximal portion of the anterior cerebral artery (A1) was evaluated using fast imaging employing steady-state acquisition (FIESTA) imaging. The outer diameter was estimated using these images, and compared with the control group, and the correlation with magnetic resonance angiography (MRA) scores was calculated for patients with moyamoya disease. RESULTS: The mean diameter of the moyamoya patient group on FIESTA was significantly lower than that of the control group in the C1, M1 and A1 (P < 0.0001). The M1 diameter on the FIESTA image showed a strong correlation with the moyamoya disease MRA score (y = (0.53x+2.31; R = 0.72), whereas the C1 diameter on the FIESTA image showed only a weak correlation (y = (0.16x+2.47; R = 0.21). CONCLUSION: We found that the outer diameter of all the vessels around the C1 was generally reduced in patients with moyamoya disease. Diameter of the MCA especially decreases as the disease progresses, similar to the negative (constrictive) remodelling pattern.

NIH Stroke Scaleを用いるAdvanced OSCEの実施と工夫 8年間807名の受験を振り返る

齊藤正樹, 山本和利, 米増保之, 小松克也, 三上毅, 外山祐一郎, 鈴木秀一郎, 松村晃寛, 寺本篤史, 射場浩介, 三國信啓, 寳金清博, 有山静香, 橋本諭, 下濱俊, 札幌医科大学医学部OSCE実施委員会

医学教育 ( (一社)日本医学教育学会 ) 46 ( Suppl. ) 177 - 177 2015年07月

Rigid endoscopic resection of deep-seated or intraventricular brain tumors.

Yukinori Akiyama, Masahiko Wanibuchi, Takeshi Mikami, Yoshifumi Horita, Katsuya Komatsu, Kengo Suzuki, Shunya Otaki, Nobuhiro Mikuni

Neurological research ( MANEY PUBLISHING ) 37 ( 3 ) 278 - 82 2015年03月 [査読有り] [国際誌]

Rigid endoscopic resection using a thick sheath (ViewSite) may be a viable method for the resection or biopsy of selected deep-seated brain tumors, such as thalamic gliomas and malignant lymphomas. Neuroendoscopic biopsy is one technique used for the histological verification of suspected brain tumors. There are a number of advantages to using this technique. For example, under direct vision, it is possible to carefully observe the tumor surface and avoid vessels during tumor resections. It is also possible to collect enough specimens for a pathological diagnosis. Eighteen consecutive patients safely underwent rigid endoscopic resection or biopsy using a thick sheath (ViewSite). The two-handed endoscopic technique that utilized a mounted rigid endoscope proved very useful and safe, since it enabled easy stanching of hemorrhages. The aim of this study was to demonstrate how to use a thick sheath for deep-seated or intraventricular tumors. The rigid endoscopic approach with a thick sheath provides an alternative medial approach with improved visualization and a wider working space.

Nascent lobar microbleeds and stroke recurrences.

Toshio Imaizumi, Shigeru Inamura, Ikuhide Kohama, Kazuhisa Yoshifuji, Tatsufumi Nomura, Katsuya Komatsu

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( ELSEVIER SCIENCE BV ) 23 ( 4 ) 610 - 7 2014年04月 [査読有り] [国際誌]

BACKGROUND: Lobar microbleeds (MBs) are occasionally visible on gradient-echo T2*-weighted (T2*-w) magnetic resonance imagings (MRIs) in patients with deep intracerebral hemorrhages (ICHs). This study investigated the contribution of nascent lobar MBs to occurrences of deep ICHs. METHODS: We prospectively analyzed nascent lobar MBs in patients admitted to our hospital who were treated with index strokes between April 2004 and November 2009. Numbers of nascent lobar MBs were counted on T2*-w MRI scans around 1 year after index strokes and compared with previous MRIs on admission. Deep ICH occurrence-free rate curves were generated by the Kaplan-Meier method using the log-rank test. The odds ratio (OR) for deep ICH occurrence was derived from a multivariate logistic regression model using nascent lobar MBs and risk factors. RESULTS: We investigated MRIs (interscan interval: 14.6 ± 5.9 months) of 508 patients (207 women, 68.9 ± 11.5 years), with a follow-up period of 44.1 ± 15.4 months. Repeated T2*-w MRIs demonstrated 157 nascent lobar MBs in 62 of 508 patients. The occurrence rate of deep ICHs (1.9% per year) was significantly higher in patients with nascent lobar MBs than in those without (.5% per year, P = .012). Multivariate analyses revealed that the rate of nascent lobar MBs was significantly elevated in patients with deep ICH-type stroke recurrences (OR: 3.85, P = .020), adjusted by the presence of hypertension, diabetes mellitus, use of antithrombotic drugs, severity of white matter lesions, age, and gender. CONCLUSIONS: Though a cohort study limited the power of analyses, our findings suggested that lobar MBs might be associated with deep ICH.

Nascent deep microbleeds and stroke recurrences.

Toshio Imaizumi, Shigeru Inamura, Ikuhide Kohama, Kazuhisa Yoshifuji, Tatsufumi Nomura, Katsuya Komatsu

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( ELSEVIER SCIENCE BV ) 23 ( 3 ) 520 - 8 2014年03月 [査読有り] [国際誌]

BACKGROUND: Cerebral microbleeds (MBs) on gradient echo T2*-weighted magnetic resonance imaging (MRI) scans are associated with the severity of cerebral microangiopathies. This study investigated the contributions of nascent deep MBs to stroke recurrence. METHODS: We prospectively analyzed nascent deep MBs in patients admitted to our hospital who were treated for index strokes between April 2004 and November 2009. The number of nascent deep MBs was counted on T2*-weighted MRI scans around 1 year after the index strokes, and compared to previous MRIs on admission. Stroke recurrence-free rate curves were generated using the Kaplan-Meier method using the log-rank test. The odds ratio for nascent deep MBs was derived using a multivariate logistic regression model that was based on recurrent strokes and other risk factors. RESULTS: We evaluated the MRIs (interval between MRIs 14.6 ± 5.9 months) of 508 patients (207 women; 68.9 ± 11.5 years), with a follow-up period of 44.1 ± 15.4 months. Repeated T2*-weighted MRI scans revealed 256 nascent deep MBs in 116 of 508 patients. The incidence of deep intracerebral hemorrhage was significantly greater in patients with nascent deep MBs than those without (2.0% vs 0.4% per year, respectively; P < .0001). Multivariate analyses revealed that the rate of nascent deep MBs was significantly elevated in patients whose stroke recurrences took the form of deep intracerebral hemorrhages (odds ratio 5.41; P = .007), when adjusted for hypertension, preexisting MBs, and other risk factors. CONCLUSIONS: Our findings suggested that nascent deep MBs might be associated with stroke recurrence, in particular with deep intracerebral hemorrhage.

Antithrombotic drug uses and deep intracerebral hemorrhages in stroke patients with deep cerebral microbleeds.

Toshio Imaizumi, Shigeru Inamura, Ikuhide Kohama, Kazuhisa Yoshifuji, Tatsufumi Nomura, Katsuya Komatsu

Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association ( 6 ) 22 ( 6 ) 869 - 75 2013年08月 [査読有り] [国際誌]

BACKGROUND: It has been suggested that antiplatelet or anticoagulant drugs elevate the rate of intracerebral hemorrhage (ICH) in patients with cerebral microbleeds (MBs). To investigate the mechanism by which antiplatelet drugs or warfarin may contribute to deep ICH occurrences in patients with deep MBs, we prospectively analyzed deep ICH occurrences in 807 consecutive patients (351 females and 456 males; mean age ± standard deviation 69.8 ± 12.0 years) who were admitted to our hospital with strokes. METHODS: Occurrence-free rate curves were generated using the Kaplan-Meier method; deep ICH occurrence-free rates were compared using the log-rank test. The follow-up period was 0.5 to 71 months (mean ± standard deviation 31.6 ± 22.2 months). RESULTS: In patients with deep MBs, the rates (1.0%/year; 6 ICHs in 180 patients) of deep ICH occurrence associated with antiplatelet drugs were not significantly greater than that without the drugs (1.0%/year; 6 ICHs in 167 patients; P = .977). The incidence of deep ICHs associated with warfarin use was not significantly greater than that without warfarin use. CONCLUSIONS: Multivariate analysis revealed that the use of antiplatelet drugs or warfarin did not significantly influence the occurrence of deep ICH in patients with deep MBs. Antiplatelet drugs or warfarin did not significantly elevate the rate of deep ICHs in stroke patients with pre-existing deep MBs.

脳卒中教育としてのNIH stroke scaleの卒前医学教育とOSCE導入、卒業試験実施報告

齊藤正樹, 山本和利, 寳金清博, 米増保之, 高橋明, 小松克也, 三上毅, 今井富裕, 矢坂正弘, 岡田靖, 佐藤利夫, 下濱俊

臨床神経学 ( (一社)日本神経学会 ) 50 ( 12 ) 1238 - 1238 2010年12月

Therapeutic time window of mesenchymal stem cells derived from bone marrow after cerebral ischemia.

Katsuya Komatsu, Osamu Honmou, Junpei Suzuki, Kiyohiro Houkin, Hirofumi Hamada, Jeffery D Kocsis

Brain research ( ELSEVIER SCIENCE BV ) 1334 84 - 92 2010年06月 [査読有り] [国際誌]

Intravenous transplantation of mesenchymal stem cells (MSCs) prepared from bone marrow ameliorates functional deficits in rat cerebral infarction models. Although several hypotheses to account for these therapeutic effects have been suggested, angiogenesis is thought to be largely responsible. MSCs were intravenously infused into rats in the relatively later time points after permanent middle cerebral artery occlusion (MCAO) to determine if they could contribute to neovascularization and functional recovery. Although MRI analysis revealed that only rats receiving MSCs 7days after MCAO exhibited decreased ischemic lesion volume than the control group, all MSCs treated rats receiving MSCs up to 1month after MCAO had greater angiogenesis near the border of the ischemic lesions and showed greater functional recovery in the treadmill stress test than did control rats. Thus, these results suggest that the time window of MSC therapy is at least over 1 month after cerebral infarction in the rat permanent MCAO model, and systemic delivery of MSCs in the later phase after cerebral ischemia may have beneficial effect through an angiogenic mechanism.

尾骨部滑液包炎の1例

吉藤和久, 小柳泉, 馬場雄大, 原口浩一, 秋山幸功, 山下太郎, 小松克也, 杉野寿哉, 池田英之, 宝金清博

小児の脳神経 ( (一社)日本小児神経外科学会 ) 31 ( 2 ) 150 - 150 2006年04月

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