脳卒中科

中原 一郎

ナカハラ イチロウ  (Ichiro Nakahara)

基本情報

所属
藤田医科大学ばんたね病院 脳神経外科 教授
学位
医学博士(京都大学)

J-GLOBAL ID
201501014327047202
researchmap会員ID
7000013153

外部リンク

主要な論文

 336
  • Koji Tanaka, Cinzia Ciccacci, Shoji Matsumoto, Gulibahaer Ainiding, Ichiro Nakahara, Hidehisa Nishi, Tetsuya Hashimoto, Tsuyoshi Ohta, Nobutake Sadamasa, Ryota Ishibashi, Masanori Gomi, Makoto Saka, Haruka Miyata, Sadayoshi Watanabe, Takuya Okata, Kazutaka Sonoda, Junpei Koge, Kyoko M. Iinuma, Konosuke Furuta, Izumi Nagata, Keitaro Matsuo, Takuya Matsushita, Noriko Isobe, Ryo Yamasaki, Jun-ichi Kira
    PLOS ONE 16(8) e0254067-e0254067 2021年8月5日  
    <sec id="sec001"> <title>Background and purpose</title> The impact of the paraoxonase-1 (<italic>PON1</italic>) polymorphism, Q192R, on platelet inhibition in response to clopidogrel remains controversial. We aimed to investigate the association between carrier status of <italic>PON1</italic> Q192R and high platelet reactivity (HPR) with clopidogrel in patients undergoing elective neurointervention. </sec> <sec id="sec002"> <title>Methods</title> Post-clopidogrel platelet reactivity was measured using a VerifyNow® P2Y12 assay in P2Y12 reaction units (PRU) for consecutive patients before the treatment. Genotype testing was performed for <italic>PON1</italic> Q192R and <italic>CYP2C19*2</italic> and <italic>*3</italic> (no function alleles), and <italic>*17</italic>. PRU was corrected on the basis of hematocrit. We investigated associations between factors including carrying ≥1 <italic>PON1</italic> 192R allele and HPR defined as original and corrected PRU ≥208. </sec> <sec id="sec003"> <title>Results</title> Of 475 patients (232 men, median age, 68 years), HPR by original and corrected PRU was observed in 259 and 199 patients (54.5% and 41.9%), respectively. Carriers of ≥1 <italic>PON1</italic> 192R allele more frequently had HPR by original and corrected PRU compared with non-carriers (91.5% vs 85.2%, P = 0.031 and 92.5% vs 85.9%, P = 0.026, respectively). In multivariate analyses, carrying ≥1 <italic>PON1</italic> 192R allele was associated with HPR by original (odds ratio [OR] 1.96, 95% confidence interval [CI] 1.03–3.76) and corrected PRU (OR 2.34, 95% CI 1.21–4.74) after adjustment for age, sex, treatment with antihypertensive medications, hematocrit, platelet count, total cholesterol, and carrying ≥1 <italic>CYP2C19</italic> no function allele. </sec> <sec id="sec004"> <title>Conclusions</title> Carrying ≥1 <italic>PON1</italic> 192R allele is associated with HPR by original and corrected PRU with clopidogrel in patients undergoing elective neurointervention, although alternative results related to other genetic polymorphisms cannot be excluded. </sec>
  • Jun Tanabe, Ichiro Nakahara, Shoji Matsumoto, Yoshio Suyama, Jun Morioka, Akiko Hasebe, Sadayoshi Watanabe, Kenichiro Suyama, Kiyonori Kuwahara, Keiko Irie
    Neuroradiology 64(1) 151-159 2021年8月5日  
    PURPOSE: Endovascular treatment of posterior communicating artery aneurysms with fetal-type posterior communicating artery originating from the aneurysm dome is often challenging because, with conventional techniques, dense packing of aneurysms for posterior communicating artery preservation is difficult; moreover, flow-diversion devices are reportedly less effective. Herein, we describe a novel method called the λ stenting technique that involves deploying stents into the internal carotid artery and posterior communicating artery. METHODS: Between January 2018 and September 2020, the λ stenting technique was performed to treat eight consecutive cases of aneurysms. All target aneurysms had a wide neck (dome/neck ratio < 2), a fetal-type posterior communicating artery with hypoplastic P1, and a posterior communicating artery originating from the aneurysm dome. The origin of the posterior communicating artery from the aneurysm, relative to the internal carotid artery, was steep (< 90°: V shape). RESULTS: The maximum aneurysm size was 8.0 ± 1.9 mm (6-12 mm). The average packing density (excluding one regrowth case) was 32.7 ± 4.2% (26.8-39.1%). Initial occlusion was complete occlusion in 6 (75.0%) patients and neck remnants in 2 (25.0%) patients. Follow-up angiography was performed at 18.4 ± 11.6 months (3-38 months). There were no perioperative complications or reinterventions required during the study period. CONCLUSION: The λ stenting technique enabled dense coil packing and preservation of the posterior communicating artery. This technique enabled safe and stable coil embolization. Thus, it could become an alternative treatment option for this sub-type of intracranial aneurysms.
  • Jun Tanabe, Ichiro Nakahara, Shoji Matsumoto, Yoshio Suyama, Jun Morioka, Jumpei Oda, Akiko Hasebe, Takeya Suzuki, Sadayoshi Watanabe, Kenichiro Suyama, Tsuyoshi Ohta, Kazuhiro Murayama, Yuichi Hirose
    NEUROCRITICAL CARE 34(3) 946-955 2021年6月  
    Background The World Federation of Neurosurgical Societies (WFNS) scale is widely accepted for predicting outcomes for subarachnoid hemorrhage (SAH) patients. However, it is difficult to definitely predict outcomes for the most poor grade, WFNS grade 5. The present study aimed to investigate the prognostic ability of a novel classification using computed tomography perfusion (CTP) findings, called the cortical blood flow insufficiency (CBFI) scores. Methods CTP was performed on admission for aneurysmal SAH followed by radical treatments within 72 hours of onset. Twenty-four cerebral cortex regions of interest (ROIs) were defined. CBFI was defined as Tmax > 4 s in each ROI, and CBFI scores were calculated based on the total number of ROIs with CBFI. Using the optimal cutoff value based on receiver operating characteristics (ROC) analysis to predict patient functional outcomes, CBFI scores were divided into "high" or "low" CBFI scores. Patient functional outcomes at 90 days were categorized based on modified Rankin Scale scores (0-3, favorable group; 4-6 unfavorable group) (0-4, non-catastrophic group; 5-6, catastrophic group). Results Fifty-seven patients were included in this study, of whom 21 (36.8%) and 13 (22.8%) were in the unfavorable and the catastrophic groups, respectively. A factor predicting unfavorable and catastrophic outcomes was CBFI score cutoff value of 7 points (area under the curve, 0.73 and 0.81, respectively). In multivariable logistic regression analysis for unfavorable outcome, high CBFI scores (odds ratio (OR), 8.6; 95% confidence interval (CI), 1.1-65.4;P = 0.04) and WFNS grade 5 (OR, 30.0; 95% CI, 4.5-201.0;P < 0.001) remained as independent predictors, while for catastrophic outcome, high CBFI scores (OR, 25.3; 95% CI, 3.3-194.0;P = 0.002) and age (OR, 1.1; 95% CI, 1.0-1.2;P = 0.02) remained as independent predictors. Conversely, WFNS grade 5 was not an independent predictor of catastrophic outcomes (OR, 3.8; 95% CI, 0.6-24.0;P = 0.15). In high CBFI scores, the OR of the delayed cerebral ischemia (DCI) occurrence was 9.6 (95% CI, 1.5-61.4;P = 0.02) after adjusting for age. Conclusion High CBFI scores could predict unfavorable and catastrophic outcomes for aneurysmal SAH patients and DCI occurrence.
  • Sadayoshi Watanabe, Jumpei Oda, Ichiro Nakahara, Shoji Matsumoto, Yoshio Suyama, Akiko Hasebe, Takeya Suzuki, Jun Tanabe, Kenichiro Suyama, Yuichi Hirose
    NEUROLOGIA MEDICO-CHIRURGICA 60(6) 286-292 2020年6月  
    Mechanical thrombectomy using a retrograde approach is performed for tandem occlusion of the internal carotid artery (ICA). In our patient, a guiding catheter was easily passed by the stenosed lesion despite severe stenosis at the ICA origin. Therefore, we aimed to recanalize the occlusion of the terminal ICA without angioplasty for the stenosed lesion. When contrast was injected, a massive extravasation of contrast from the C2 portion of the ICA was observed. It was speculated that the bleeding was caused by rupture of an aneurysm at that site due to increased intra-arterial pressure caused by the contrast injection to a blind alley, which was created by a wedged guiding catheter at severe stenosis at the ICA origin and the occlusion of the terminal ICA. Our simulation experiment using a silicon vascular model in this situation demonstrated that the elevation of intra-arterial pressure in such blind alley reached over 50, 100, and 200 mmHg by injection of contrast from a microcatheter, a 4-Fr inner catheter, and a 9-Fr balloon-guiding catheter, respectively. When a retrograde approach is planned for tandem occlusion of the ICA, even when the proximal lesion is easily passed, prior angioplasty for the proximal lesion should be considered to avoid wedging by catheter.
  • Yoshihisa Fukushima, Kenji Takahashi, Ichiro Nakahara
    Interventional Neuroradiology 26(3) 341-345 2020年6月1日  
  • Junpei Koge, Shoji Matsumoto, Ichiro Nakahara, Akira Ishii, Taketo Hatano, Yujiro Tanaka, Daisuke Kondo, Jun-ichi Kira, Izumi Nagata
    Journal of the Neurological Sciences 412 116737-116737 2020年5月  
  • Hidehisa Nishi, Naoya Oishi, Akira Ishii, Isao Ono, Takenori Ogura, Tadashi Sunohara, Hideo Chihara, Ryu Fukumitsu, Masakazu Okawa, Norikazu Yamana, Hirotoshi Imamura, Nobutake Sadamasa, Taketo Hatano, Ichiro Nakahara, Nobuyuki Sakai, Susumu Miyamoto
    Stroke 51(5) 1484-1492 2020年5月  査読有り
    <sec> <title>Background and Purpose—</title> For patients with large vessel occlusion, neuroimaging biomarkers that evaluate the changes in brain tissue are important for determining the indications for mechanical thrombectomy. In this study, we applied deep learning to derive imaging features from pretreatment diffusion-weighted image data and evaluated the ability of these features in predicting clinical outcomes for patients with large vessel occlusion. </sec> <sec> <title>Methods—</title> This multicenter retrospective study included patients with anterior circulation large vessel occlusion treated with mechanical thrombectomy between 2013 and 2018. We designed a 2-output deep learning model based on convolutional neural networks (the convolutional neural network model). This model employed encoder-decoder architecture for the ischemic lesion segmentation, which automatically extracted high-level feature maps in its middle layers, and used its information to predict the clinical outcome. Its performance was internally validated with 5-fold cross-validation, externally validated, and the results compared with those from the standard neuroimaging biomarkers Alberta Stroke Program Early CT Score and ischemic core volume. The prediction target was a good clinical outcome, defined as a modified Rankin Scale score at 90-day follow-up of 0 to 2. </sec> <sec> <title>Results—</title> The derivation cohort included 250 patients, and the validation cohort included 74 patients. The convolutional neural network model showed the highest area under the receiver operating characteristic curve: 0.81±0.06 compared with 0.63±0.05 and 0.64±0.05 for the Alberta Stroke Program Early CT Score and ischemic core volume models, respectively. In the external validation, the area under the curve for the convolutional neural network model was significantly superior to those for the other 2 models. </sec> <sec> <title>Conclusions—</title> Compared with the standard neuroimaging biomarkers, our deep learning model derived a greater amount of prognostic information from pretreatment neuroimaging data. Although a confirmatory prospective evaluation is needed, the high-level imaging features derived by deep learning may offer an effective prognostic imaging biomarker. </sec>
  • Sadayoshi Watanabe, Shoji Matsumoto, Ichiro Nakahara, Akira Ishii, Taketo Hatano, Minako Mori, Eriko Morishita, Izumi Nagata
    FRONTIERS IN NEUROLOGY 11 2020年2月  
    Objective: A rare case of thromboembolic cerebral infarction due to carotid web in a patient with congenital protein C deficiency is reported.Case Presentation: A patient in her 40's with left-side hemiparesis was transferred to our hospital under continuous intravenous injection of heparin. Magnetic resonance angiography demonstrated occlusion of the right middle cerebral artery (MCA). Conventional angiography revealed recanalization of the right MCA and a carotid web at the origin of the right internal carotid artery. Ultrasound scan of the carotid artery on the 19th day revealed thrombus formation on the distal portion of the carotid web. We performed carotid artery stenting to prevent thrombus formation by suppressing the carotid web to the vessel wall and by regulating the turbulent flow. The patient had no recurrence of stroke under-anticoagulation with warfarin during the 2-year follow-up period.Conclusion: To our knowledge, this is the first report in which an immediate thrombus formation on the carotid web was observed in a patient with congenital protein C deficiency. In a case of acute ischemic stroke with carotid web, especially when congenital coagulopathy such as protein C deficiency is suspected, careful follow-up with ultrasound imaging should be performed.
  • Keitaro Yamagami, Taketo Hatano, Ichiro Nakahara, Akira Ishii, Mitsushige Ando, Hideo Chihara, Takenori Ogura, Keita Suzuki, Daisuke Kondo, Takahiko Kamata, Eiji Higashi, Shota Sakai, Hiroki Sakamoto, Koji Iihara, Izumi Nagata
    World Neurosurgery 134 e289-e297 2020年2月  査読有り
    BACKGROUND: The long-term outcomes of patients with intraprocedural aneurysm rupture (IPR) during endovascular coiling of unruptured intracranial aneurysms (UIAs) remain unclear. We investigated the long-term outcomes and predictors of neurological outcomes in patients who sustained IPR during coil embolization of UIAs. METHODS: We retrospectively analyzed the medical record of 312 untreated UIAs in 284 patients who underwent endovascular coiling between April 2013 and July 2018. RESULTS: The mean follow-up period for the entire cohort was 25.6 months. Twelve patients (3.8%) experienced IPR. The mean aneurysm size in the IPR cohort was significantly smaller than that in the no-IPR cohort (P = 0.045). The IPR cohort had a higher percentage of earlier subarachnoid hemorrhage from another aneurysm (P = 0.019), anterior communicating artery (AComA) aneurysm (P < 0.001), and basilar artery (BA) aneurysm (P = 0.022) than the no-IPR cohort. Neurologic deterioration was observed in 3 patients. The morbidity and mortality rates of the IPR cohort were 25% and 8.3%, respectively. Patients with IPR during coil embolization for AComA aneurysm did not develop neurological deterioration. Two of the 3 patients (66.7%) with a BA aneurysm had neurological deterioration. The proportion of patients with an mRS score of 0-2 at the last follow-up did not differ between the 2 cohorts (P = 0.608). CONCLUSIONS: The proportion of functionally independent patients did not differ between patients with and without IPR. Patients with BA aneurysms who developed an IPR tended to exhibit more unfavorable clinical courses than patients with AcomA aneurysms.
  • Ohta T, Nakahara I, Matsumoto S, Kondo D, Watanabe S, Okada K, Fukuda M, Masahira N, Tsuno T, Matsuoka T, Takemura M, Fukuda H, Fukui N, Ueba T
    Neurology 93(22) e1997-e2006 2019年11月  査読有り
  • Tokunaga K, Hatano T, Nakahara I, Ishii A, Higashi E, Kamata T, Funakoshi Y, Hashikawa T, Takita W, Chihara H, Ando M, Sadamasa N, Kitazono T, Nagata I
    World neurosurgery 130 E457-E462 2019年10月  査読有り
  • Nishi H, Oishi N, Ishii A, Ono I, Ogura T, Sunohara T, Chihara H, Fukumitsu R, Okawa M, Yamana N, Imamura H, Sadamasa N, Hatano T, Nakahara I, Sakai N, Miyamoto S
    Stroke 50(9) 2379-2388 2019年9月  査読有り
  • Sadayoshi Watanabe, Ichiro Nakahara, Tsuyoshi Ohta, Shoji Matsumoto, Ryota Ishibashi, Izumi Nagata
    JOURNAL OF STROKE & CEREBROVASCULAR DISEASES 28(2) 464-469 2019年2月  査読有り
    Objective: We report a case of a 70-year-old man who developed a transverse-sigmoid dural arteriovenous fistula (TS-DAVF) that was successfully treated by transarterial embolization (TAE) with Onyx. Case Presentation: The patient presented with sudden and progressive disturbance of consciousness and left hemiparesis. Magnetic resonance imaging (MRI) revealed venous infarction and hemorrhagic changes with brain swelling in the right parietal lobe. Angiography revealed a right TS-DAVF and multiple occlusions with retrograde leptomeningeal venous drainage into the cortical veins. The TS-DAVF was graded as Borden type III and Cognard type IIa+b. Because of its progressive clinical nature and wide distribution of DAVF in the occluded sinus wall, he underwent emergent TAE with liquid embolic materials including n-butyl cyanoacrylate and Onyx under informed consent by his family. Complete obliteration of the TS-DAVF was achieved, leading to a marked amelioration of symptoms, and MRI after treatment confirmed a decrease in the brain swelling. However, he suffered transient dysphagia due to right vagal nerve palsy caused by occlusion of vasa nervorum of ascending pharyngeal artery. He returned home 5 months later with a modified Rankin Scale of 1. Conclusions: TAE with Onyx appears to be effective for aggressive TS-DAVF with a widely distributed shunt. However, the blood supply to the cranial nerves and potentially dangerous anastomoses between the external-internal carotid artery and vertebral artery should be taken into account to avoid serious complications.
  • Shoji Matsumoto, Hiroshi Koyama, Ichiro Nakahara, Akira Ishii, Taketo Hatano, Tsuyoshi Ohta, Koji Tanaka, Mitsushige Ando, Hideo Chihara, Wataru Takita, Keisuke Tokunaga, Takuro Hashikawa, Yusuke Funakoshi, Takahiko Kamata, Eiji Higashi, Sadayoshi Watanabe, Daisuke Kondo, Atsushi Tsujimoto, Konosuke Furuta, Takuma Ishihara, Tetsuya Hashimoto, Junpei Koge, Kazutaka Sonoda, Takako Torii, Hideaki Nakagaki, Ryo Yamasaki, Izumi Nagata, Jun-Ichi Kira
    Frontiers in neurology 10 1118-1118 2019年  査読有り
    Background: To maximize the effect of intravenous (IV) thrombolysis and/or endovascular therapy (EVT) for acute ischemic stroke (AIS), stroke centers need to establish a parallel workflow on the basis of a code stroke (CS) protocol. At Kokura Memorial Hospital (KMH), we implemented a CS system in January 2014; however, the process of information sharing within the team has occasionally been burdensome. Objective: To solve this problem using information communication technology (ICT), we developed a novel application for smart devices, named "Task Calc. Stroke" (TCS), and aimed to investigate the impact of TCS on AIS care. Methods: TCS can visualize the real-time progress of crucial tasks for AIS on a dashboard by changing color indicators. From August 2015 to March 2017, we installed TCS at KMH and recommended its use during normal business hours (NBH). We compared the door-to-computed tomography time, the door-to-complete blood count (door-to-CBC) time, the door-to-needle for IV thrombolysis time, and the door-to-puncture for EVT time among three treatment groups, one using TCS ("TCS-based CS"), one not using TCS ("phone-based CS"), and one not based on CS ("non-CS"). A questionnaire survey regarding communication problems was conducted among the CS teams at 3 months after the implementation of TCS. Results: During the study period, 74 patients with AIS were transported to KMH within 4.5 h from onset during NBH, and 53 were treated using a CS approach (phone-based CS: 26, TSC-based CS: 27). The door-to-CBC time was significantly reduced in the TCS-based CS group compared to the phone-based CS group, from 31 to 19 min (p = 0.043). Other processing times were also reduced, albeit not significantly. The rate of IV thrombosis was higher in the TCS-based CS group (78% vs. 46%, p = 0.037). The questionnaire was correctly filled in by 34/38 (89%) respondents, and 82% of the respondents felt a reduction in communication burden by using the TCS application. Conclusions: TCS is a novel approach that uses ICT to support information sharing in a parallel CS workflow in AIS care. It shortens the processing times of critical tasks and lessens the communication burden among team members.
  • Koyanagi M, Ishii A, Imamura H, Satow T, Yoshida K, Hasegawa H, Kikuchi T, Takenobu Y, Ando M, Takahashi JC, Nakahara I, Sakai N, Miyamoto S
    Journal of neurosurgery 129(6) 1-7 2018年1月  査読有り
    OBJECTIVELong-term follow-up results of the treatment of unruptured intracranial aneurysms (UIAs) by means of coil embolization remain unclear. The aim of this study was to analyze the frequency of rupture, retreatment, stroke, and death in patients with coiled UIAs who were followed for up to 20 years at multiple stroke centers.METHODSThe authors retrospectively analyzed data from cases in which patients underwent coil embolization between 1995 and 2004 at 4 stroke centers. In collecting the late (≥ 1 year) follow-up data, postal questionnaires were used to assess whether patients had experienced rupture or retreatment of a coiled aneurysm or any stroke or had died.RESULTSOverall, 184 patients with 188 UIAs were included. The median follow-up period was 12 years (interquartile range 11-13 years, maximum 20 years). A total of 152 UIAs (81%) were followed for more than 10 years. The incidence of rupture was 2 in 2122 aneurysm-years (annual rupture rate 0.09%). Nine of the 188 patients with coiled UIAs (4.8%) underwent additional treatment. In 5 of these 9 cases, the first retreatment was performed more than 5 years after the initial treatment. Large aneurysms were significantly more likely to require retreatment. Nine strokes occurred over the 2122 aneurysm-years. Seventeen patients died in this cohort.CONCLUSIONSThis study demonstrates a low risk of rupture of coiled UIAs with long-term follow-up periods of up to 20 years. This suggests that coiling of UIAs could prevent rupture for a long period of time. However, large aneurysms might need to be followed for a longer time.
  • Nishi H, Ishii A, Nakahara I, Matsumoto S, Sadamasa N, Kai Y, Ishibashi R, Yamamoto M, Morita S, Nagata I
    Journal of neurosurgery 1-8 2018年1月  査読有り
  • Koge J, Matsumoto S, Nakahara I, Ishii A, Hatano T, Sadamasa N, Kai Y, Ando M, Saka M, Chihara H, Takita W, Tokunaga K, Kamata T, Nishi H, Nagata I
    Journal of the neurological sciences 381 68-73 2017年10月  査読有り
    Background. Previous reports have shown significant delays in treatment of in-hospital stroke (IHS). We developed and implemented our IHS alert protocol in April 2014. We aimed to determine the influence of implementation of our IHS alert protocol. Methods: Our implementation processes comprise the following four main steps: IHS protocol development, workshops for hospital staff to learn about the protocol, preparation of standardized IHS treatment kits, and obtaining feedback in a monthly hospital staff conference. We retrospectively compared protocol metrics and clinical outcomes of patients with IHS treated with intravenous thrombolysis and/or endovascular therapy between before (January 2008 March 2014) and after implementation (April 2014 December 2016). Results: Fifty-five patients were included (pre, 25; post, 30). After the implementation, significant reductions occurred in the median time from stroke recognition to evaluation by a neurologist (30 vs. 13.5 min, p &lt; 0.01) and to first neuroimaging (50 vs. 26.5 min, p &lt; 0.01) and in the median time from first neuroimaging to intravenous thrombolysis (45 vs. 16 min, p = 0.02). The median time from first neuroimaging to endovascular therapy had a tendency to decrease (75 vs. 53 min, p = 0.08). There were no differences in the favorable outcomes (modified Rankin scale score of 0-2) at discharge or the incidence of symptomatic intracranial hemorrhage between the two periods. Conclusion: Our IHS alert protocol implementation saved time in treating patients with IHS without compromising safety.
  • Ohta T, Nakahara I, Matsumoto S, Ishibashi R, Miyata H, Nishi H, Watanabe S, Nagata I
    NEUROSURGERY 81(3) 512-519 2017年3月  査読有り
    BACKGROUND: Definitive preoperative predictors of cerebral hyperperfusion following carotid artery stenting are yet to be established. OBJECTIVE: To determine the preprocedural risk factors for cerebral hyperperfusion phenomenon (CHP) following carotid artery stenting. METHODS: Patients undergoing preprocedural single-photon emission computed tomography (SPECT) and cerebral angiography prior to their first carotid artery stenting were monitored for occurrence of CHP. In addition to patient characteristics, we investigated imaging parameters, such as cerebral blood flow, cerebral vasoreactivity, and asymmetry index on SPECT, and presence of near occlusion and leptomeningeal anastomosis on cerebral angiography. RESULTS: Out of 100 patients (mean age: 73.0 +/- 7.6 years; 85 men), 9 developed CHP. On multivariate logistic regression analysis, asymmetry index (%) on SPECT (odds ratio [OR] 0.81, 95% confidence interval [CI] 0.70-0.93, P = .003) and presence of leptomeningeal anastomosis on cerebral angiography (OR 72.1, 95% CI 3.52-1480, P = .006) were independent predictors of CHP. CONCLUSION: Combined use of cerebral angiography and SPECT may obviate the need for acetazolamide challenge to predict the risk of CHP following carotid artery stenting.
  • Nishi H, Nakahara I, Matsumoto S, Hashimoto T, Ohta T, Sadamasa N, Ishibashi R, Gomi M, Saka M, Miyata H, Watanabe S, Okata T, Sonoda K, Kouge J, Ishii A, Nagata I, Kira JI
    JOURNAL OF NEUROINTERVENTIONAL SURGERY 8(9) 949-953 2015年8月  査読有り
    Background and purpose Hemorrhagic complications during neurointerventional procedures have various etiologies and can result in severe morbidity and mortality. This study investigated the possible association between low platelet reactivity measured by the VerifyNow assay and increased hemorrhagic complications during elective neurointervention under dual antiplatelet therapy. Methods From May 2010 to April 2013 we recorded baseline characteristics, P2Y12 reaction units (PRU), and aspirin reaction units using VerifyNow. The primary endpoint was post-procedural hemorrhagic complications. Results A total of 279 patients were enrolled and 31 major hemorrhagic complications (11.1%) were identified. From receiver-operating characteristic curve analysis, PRU values could discriminate between patients with and without major hemorrhagic complications (area under the curve 0.63). Aspirin reaction unit values had no association with the primary outcome. The optimal cut-off for the primary outcome (PRU &lt;= 175) was used to identify the low platelet reactivity group. The incidence of hemorrhagic complications was 20.0% in this group and 8.9% in the non-low platelet reactivity group. Multivariate analysis identified low platelet reactivity as an independent predictor for hemorrhagic complications. Conclusions The risk of hemorrhagic complications during elective neurointervention including cerebral aneurysm coil embolization and carotid artery stenting under dual antiplatelet therapy is associated with the response to clopidogrel but not to aspirin. A PRU value of &lt;= 175 discriminates between patients with and without hemorrhagic complications. Future prospective studies are required to validate whether a specific PRU value around 170-180 is predictive of hemorrhagic complications.
  • Ohta T, Nakahara I, Ishibashi R, Matsumoto S, Gomi M, Miyata H, Nishi H, Watanabe S, Nagata I
    AMERICAN JOURNAL OF NEURORADIOLOGY 36(4) 744-750 2015年4月  査読有り
    These authors describe the use of 2 intra-aneurysmal catheters to deploy first large coils and then smaller, more traditional coils that ultimately fill the interstices left by the larger coils until aneurysms are tightly packed. When this technique was used to occlude large/giant aneurysms, follow-up angiography revealed no recurrences compared with nearly 40% in a group of similar lesions treated in conventional fashion. BACKGROUND AND PURPOSE: Despite major progress in treating aneurysms by coil embolization, the complete occlusion of aneurysms of &gt;10 mm in diameter (large/giant aneurysms) remains challenging. We present a novel endovascular treatment method for large and giant cerebral aneurysms called the maze-making and solving technique and compare the short-term follow-up results of this technique with those of conventional coil embolization. MATERIALS AND METHODS: Eight patients (65 11.5 years of age, 7 women) with large/giant unruptured nonthrombosed cerebral aneurysm (mean largest aneurysm dimension, 19 4.4 mm) were treated by the maze-making and solving technique, a combination of the double-catheter technique and various assisted techniques. The coil-packing attenuation, postoperative courses, and recurrence rate of this maze group were compared with 30 previous cases (conventional group, 65.4 +/- 13.0 years of age; 22 women; mean largest aneurysm dimension, 13.4 +/- 3.8 mm). RESULTS: Four maze group cases were Raymond class 1; and 4 were class 2 as indicated by immediate postsurgical angiography. No perioperative deaths or major strokes occurred. Mean packing attenuation of the maze group was significantly higher than that of the conventional group (37.4 +/- 5.9% versus 26.2 +/- 5.6%). Follow-up angiography performed at 11.3 +/- 5.4 months revealed no recurrence in the maze group compared with 39.2% in the conventional group. CONCLUSIONS: The maze-making and solving technique achieves high coil-packing attenuation for efficient embolization of large and giant cerebral aneurysms with a low risk of recurrence.
  • Takayama K, Taki W, Toma N, Nakahara I, Maeda M, Tanemura H, Kuroiwa T, Imai K, Sakamoto M, Nakagawa I, Masuo O, Myouchin K, Wada T, Suzuki H
    CARDIOVASCULAR AND INTERVENTIONAL RADIOLOGY 37(6) 1436-1443 2014年12月  査読有り
    Periprocedural ischemic stroke is one problem associated with carotid artery stenting (CAS). This study was designed to assess whether preoperative statin therapy reduces the risk of periprocedural ischemic complications with CAS. In this prospective study at 11 centers, patients with carotid artery stenosis (symptomatic a parts per thousand yen50 %, asymptomatic a parts per thousand yen80 %) and a high risk of carotid endarterectomy but without previous statin treatments were divided into two groups by low-density lipoprotein cholesterol (LDL-C) levels. With LDL-C a parts per thousand yen120 mg/dl, the pitavastatin-treated (PS) group received pitavastatin at 4 mg/day. With LDL-C &lt; 120 mg/dl, the non-PS group received no statin therapy. After 4 weeks, both groups underwent CAS. Frequencies of new ipsilateral ischemic lesions on diffusion-weighted imaging within 72 h after CAS and cerebrovascular events (transient ischemic attack, stroke, or death) within 30 days were assessed. Among the 80 patients enrolled, 61 patients (PS group, n = 31; non-PS group, n = 30) fulfilled the inclusion criteria. New ipsilateral ischemic lesions were identified in 8 of 31 patients (25.8 %) in the PS group and 16 of 30 patients (53.3 %) in the non-PS group (P = 0.028). Cerebrovascular events occurred in 0 patients in the PS group and in 3 of 30 patients (10.0 %) in the non-PS group (P = 0.071). Multivariate analyses demonstrated the pitavastatin treatment (beta = 0.74, 95 % confidence interval 0.070-1.48, P = 0.042) to be an independent factor for decreasing post-CAS ischemic lesions. Pretreatment with pitavastatin significantly reduced the frequency of periprocedural ischemic complications with CAS.
  • Miyachi S, Taki W, Sakai N, Nakahara I, Japanese CAS Survey Investigators
    ACTA NEUROCHIRURGICA 154(12) 2127-2137 2012年12月  査読有り
    We conducted a large retrospective survey of the clinical results of carotid artery stenting (CAS) for about 10 years performed by neurointerventionists at 43 Japanese institutions. Hence, the historical perspective of CAS in Japan was demonstrated. Cases were stratified into three separate periods based on the approval status of devices: the first period, in which off-label CAS was performed using balloon protection; the second period, using a limited number of approved devices under filter protection; the third period, using appropriate protection selected from several different options based on the preoperative evaluation (tailored CAS). Clinical results were retrospectively evaluated. Then 30-day results of each period were examined. The major adverse event (MAE) was defined as stroke, myocardial infarction or death. Between January 2001 and December 2010, a total of 8,092 cases were registered, including 4,072, 1,526 and 2,494 in the first, second and third period, respectively. In the first period, 92 % of CAS was performed under balloon protection. In contrast, 91 % was done under filter protection in the second period. In the third period, various protection methods were used, including balloon (31 %), filter (50 %) and proximal protection (18 %). The rate of MAE at 30 days was 6.1 %, 10.2 % and 3.5 % in the first, second and third periods, respectively, and 6.3 % in all periods combined. The rate of MAE in the third period was significantly lower than that in the first and second periods. The historical paradigm of CAS in Japan was demonstrated. Due to the improvement of devices, increasing experience and appropriate selection of protection, CAS is continuing to evolve into a safer and more efficacious method of stroke prevention.
  • Kakumoto K, Matsumoto S, Nakahara I, Watanabe Y, Fukushima Y, Yoshikiyo U, Ishibashi R, Gomi M, Tsuji K, Sanbongi Y, Hashimoto T, Tanaka Y, Yamada T, Kira J
    Cerebrovascular diseases extra 2(1) 9-16 2012年  査読有り
    Kakumoto K, Matsumoto S, Nakahara I, Watanabe Y, Fukushima Y, Yoshikiyo U, Ishibashi R, Gomi M, Tsuji K, Sanbongi Y, Hashimoto T, Tanaka Y, Yamada T, Kira J, Cerebrovascular diseases extra, 2012, vol. 2, no. 1, pp. 9-16
  • Nakahara I, Higashi T, Iwamuro Y, Watanabe Y, Nakagaki H, Takezawa M, Murata D, Taha M
    NEUROSURGERY 66(5) 876-882 2010年5月  査読有り
    OBJECTIVE: Endovascular stenting is an alternative treatment for brachiocephalic artery stenosis, replacing standard surgical approaches such as carotid endarterectomy. However, a percutaneous approach may be difficult because various conditions such as severe arteriosclerosis of iliac or femoral arteries and aortic disease. We report our experience with intraoperative stenting for these lesions, presenting indications, strategy, and results. METHODS: Seven patients underwent intraoperative stent placement via an open cervical approach. The sites of lesions included 1 innominate artery, 1 common carotid artery, and 5 cervical carotid arteries. Stenting was performed with a sheath introducer placed through a surgically exposed common carotid artery via a small skin incision or common carotid artery exposed for simultaneously performed carotid endarterectomy. Distal protection was used in 6 patients with an endovascular protective balloon or external clamping with forceps. RESULTS: Sufficient dilation of stenosis was obtained in all cases. No complications such as transient ischemic attack, cerebral infarction, and hyperperfusion were encountered. Wound hematoma was not experienced despite perioperative antiplatelet therapy and heparinization during the procedure. Angiographic follow-up over 1 year showed no restenosis in 5 available patients. CONCLUSION: Intraoperative stenting may be an excellent alternative for patients in whom both direct surgical approach and standard percutaneous endovascular approach are not possible.
  • Matsumoto S, Nakahara I, Higashi T, Iwamuro Y, Watanabe Y, Takezawa M, Murata D, Yokota T, Kira J, Yamada T
    CEREBROVASCULAR DISEASES 29(5) 468-475 2010年  査読有り
    Objectives: This study aimed to evaluate the relationship between the amount of aspirated debris during distal balloon-protected carotid artery stenting (CAS) and the pre-intervention plaque composition, as assessed by Virtual Histology TM (VH) intravascular ultrasound (IVUS). Methods: The study subjects were 25 consecutive patients (mean age, 73.0 +/- 5.2 years; 20 males and 5 females) who underwent CAS under distal balloon protection. The average rate of carotid stenosis was 74.6 +/- 12.9% by North American Symptomatic Carotid Endarterectomy Trial criteria. We assessed culprit plaque components by VH-IVUS before CAS. Aspirated debris was filtered, stained with HE and mounted onto glass slides. The quantity of debris was evaluated by measuring its surface area. We evaluated the relationship between the quantity of aspirated debris and VH-IVUS measurements before CAS. Results: The amount of debris during CAS was positively correlated with the total plaque volume in grayscale IVUS (Rs = 0.480, p = 0.015) and fibro-fatty volumes over the entire lesion length in VH-IVUS (Rs = 0.561, p = 0.001). Conclusions: Culprit lesions with large plaque volumes, especially larger fibro-fatty volumes, as imaged by VH-IVUS, are associated with large amounts of debris during balloon-protected CAS. Copyright (C) 2010 S. Karger AG, Basel
  • Taha MM, Nakahara I, Higashi T, Iwamuro Y, Watanabe Y, Taki W
    NEUROLOGIA MEDICO-CHIRURGICA 50(4) 275-280 2010年  査読有り
    Aneurysms in the supra-aortic extracranial arteries are rare in neurovascular pathology. Conventional surgery is effective but technically demanding and successful endovascular repair is reported. We treated 5 patients with supra-aortic extracranial artery aneurysms at our hospital (mean age 53.8 years). There were 2 aneurysms of the common carotid artery, 1 of the extracranial internal carotid artery, 1 of the subclavian artery, and 1 located at the innominate artery. Four patients were symptomatic. The lesion was the result of trauma in 3 patients. The procedure was conducted using bare stent placement and coil embolization of the aneurysm in 2 patients, covered stent in 2 patients, and bare stent only in 1 patient. No periprocedural complications occurred. Follow-up angiography revealed asymptomatic stent thrombosis in a patient treated using a covered stent, but the remaining 4 patients showed successful treatment of the aneurysms with the parent arteries remaining patent. Follow-up clinical assessment ranged between 30 and 81 months. The patient with stent thrombosis died of unrelated pathology; the remaining patients did not experience aneurysm recurrence, hemorrhage, or distal thromboembolism.
  • Matsumoto S, Nakahara I, Higashi T, Iwamuro Y, Watanabe Y, Takahashi K, Ando M, Takezawa M, Kira JI
    NEUROLOGY 72(17) 1512-1518 2009年4月  査読有り
    Objective: Cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS) or carotid endarterectomy (CEA) is rare but often fatal once intracranial hemorrhage has occurred. In particular, CHS occurs significantly earlier after CAS than after CEA. Thus a monitoring method for early detection of CHS is required. Near-infrared spectroscopy (NIRS) provides a non-invasive monitoring technique for assessing regional cerebral oxygen saturation (rSO(2)). This study evaluated the usefulness of transcranial NIRS during CAS for prediction of CHS. Methods: Periprocedural rSO(2) was monitored in 64 cases of CAS (52 men, 12 women; 71 +/- 6.6 years). The average degree of carotid stenosis was 76.8 +/- 11.3% by North American Symptomatic Carotid Endarterectomy Trial criteria. Bifrontal rSO(2) was monitored during the procedure using NIRS. Seventeen patients were symptomatic and 47 were asymptomatic. CHS was diagnosed by increased cerebral blood flow by SPECT performed on the day after treatment with deterioration of neurologic symptoms. Results: CHS was observed in two cases (3.1%). In the CHS group, post-reperfusion rSO(2) values increased &gt;24% from baseline until 3 minutes after reperfusion. In the non-CHS group, the normal upper limit (NUL) of the rSO(2) change was set at 10.0% at 3 minutes after reperfusion. In the CHS group, rSO(2) at 3 minutes after reperfusion was markedly higher than the NUL. In patients showing an rSO(2) at 3 minutes after reperfusion increased by more than 10.0%, CHS following CAS could be predicted. Conclusion: Periprocedural increases in regional cerebral oxygen saturation measured by near-infrared spectroscopy can be an excellent predictor of cerebral hyperperfusion syndrome after carotid artery stenting. Neurology (R) 2009; 72: 1512-1518
  • Nakahara I, Taha MM, Higashi T, Iwamuro Y, Iwaasa M, Watanabe Y, Tsunetoshi K, Munemitsu T
    SURGICAL NEUROLOGY 66(4) 405-410 2006年10月  査読有り
    Background: Intracranial mycotic aneurysms, although rare neurovascular pathology, represented a neurosurgical challenge that required careful stepwise decision making. Different approaches for their management were used. We present our experience with 4 patients treated in terms of indications and efficacy of different treatment modalities. Methods: Four patients with infective endocarditis and 5 intracranial mycotic aneurysms were treated during the last 5 years. All of the patients were men; their ages ranged between 29 and 62 years (mean, 47.3 years). Distal MCA was the commonest site Q patients) of aneurysm, I was located at the distal PCA, whereas the remaining aneurysm was at the distal ACA. Angiographic studies were done in 2 patients because of neurologic signs and for screening in 2 patients with documented endocarditis. Results: One patient was treated conservatively because of his moribund general condition; I patient was treated with direct surgical clipping; I patient was treated with surgical trapping and resection of the aneurysm without revascularization; and the remaining patient, harboring 2 distal mycotic aneurysms, was treated with selective embolization for his PCA aneurysm and endovascular trapping for the distal ACA aneurysm. Follow-up angiographic results showed stable occlusion of the aneurysms. No periprocedural technical complications were reported, and none of the patients, including the patient with medical treatment only, has ever experienced new neurologic events after definitive treatment. Conclusions: Prolonged courses of antibiotics are recommended for all patients with mycotic aneurysms. Selective endovascular embolization or trapping with soft and ultrasoft electrolytically detachable coils seems to be an effective technique that should be considered for treatment of dynamic unruptured mycotic aneurysms, with conventional surgical repair restricted for ruptured aneurysms with associated hematoma. and high intracranial pressure. (c) 2006 Elsevier Inc. All rights reserved.
  • Taha MM, Nakahara I, Higashi T, Iwamuro Y, Iwaasa M, Watanabe Y, Tsunetoshi K, Munemitsu T
    SURGICAL NEUROLOGY 66(3) 277-284 2006年9月  査読有り
    Background: Enclovascular embolization of cerebral aneurysms has evolved rapidly worldwide within the last years, and has gained more popularity at the expense of surgical clipping; however, both regimens have inherent risks. This study was undertaken to asses the cerebral complications associated with both modalities of cerebral aneurysm treatment. Methods: We retrospectively reviewed the charts, operative and embolization reports, and imaging of patients who underwent surgical clipping or embolization for cerebral aneurysms at our institution between October 2001 and October 2004. Patients were divided into 2 groups: group A, patients who had confirmed subarachnoid hemorrhage; group 13, patients with unruplured cerebral aneurysms. Patients belonging to group A were evaluated according to the Hunt and Hess scale with their computed tomography scan evaluated according to Fisher scale. Short-term outcome was measured with Glasgow Outcome Scale for both groups. Results: One hundred thirty-three patients with 168 aneurysms were treated; 95 (71.4%) were women and 38 (28.6%) men; mean age was 60.28 years. Hypertension (29.6%) was the most commonly encountered risk factor; average size of aneurysms treated was 7.21 MITI; 53 patients belonged to group A. Seven patients were Hunt and Hess grade I, 23 grade II, 11 grade III, 7 grade IV, and 5 grade V Eighty patients belonged to group 13; for both groups, the periprocedural technical complication rate associated with coiling was 8.4% vs 19.35% with clipping. Follow-up angiographic results were better with clipping, as total aneurysm occlusion was 81.4% vs 57.5% with coiling. In group A, the incidence of angiographic vasospasm was 17.4% vs 45.4% with coiling vs clipping, whereas the incidence of shunt-dependant hydrocephalus was comparable with embolization and clipping. In group A, excellent outcome was achieved in 62% vs 44% (endovascular vs surgical) of subgroups, whereas in group B, it was 93% vs 81%, respectively. Conclusion: With rapidly evolving technology of endovascular embolization, accumulated experience, and good selection of patients with optimum angioanatomical criteria and endovascular accessibility, our results of morbidity and mortality associated with both modalities of cerebral aneurysm treatment with short-term outcome show that endovascular embolization of cerebral aneurysms is a safe alternative to surgical clipping in the treatment of both ruptured and unruptured cerebral aneurysms; however, long-term outcome needs to be evaluated. (c) 2006 Elsevier Inc. All rights reserved.
  • Sheikh B, Nakahara I, El-Naggar A, Nagata I, Kikuchi H
    INTERVENTIONAL NEURORADIOLOGY 6 139-142 2000年11月  査読有り
    A grading system was designed by the first author (B.S.) specifically to predict the difficulty of endovascular obliteration of an intracranial arteriovenous malformation based on the feeding arterial characteristics, and the venous drainage system. We have retrospectively reviewed our cases of intracranial arteriovenous malformation, with special interest in chose underwent endovascular embolization. The grading of the AVM was by either our new proposed system or by a surgically oriented grading system. Both systems were compared from the endovascular point of view. Using the present proposed grading system intracranial arteriovenous malformation may range from grade I to grade V. The difficulty of the endovascular embolization correlated well with the new grading system, while in most cases if did not reflect the degree of difficulty of the procedure when a pure surgical grading system was used. This newly designed grading system has a better prediction value to the difficulty of performing endovascular embolization than does other grading systems.
  • Nakahara I, Taki W, Kikuchi H, Sakai N, Isaka F, Oowaki H, Kondo A, Iwasaki K, Nishi S
    NEURORADIOLOGY 41(1) 60-66 1999年1月  査読有り
    The association between intracranial aneurysms and arteriovenous malformations (AVMs) is well documented. Recent advances in the understanding of the haemodynamics of this association encourage an aggressive approach to these aneurysms. However, the pathophysiology of these aneurysms is not fully understood and a strategy for their management has not been established. We describe seven patients, with eight aneurysms, on the feeding arteries of AVMs. The aneurysms could be divided into those located 1. proximally on the superficial feeding artery (type I; 4 aneurysms): 2. distally on the superficial feeding artery (type II: 3 aneurysms); and 3. on the deep feeding artery (type Iii, 1 aneurysm). All aneurysms were treated by the endovascular procedure prior to, or simultaneously with, treatment of the AVM, using detachable coils or liquid embolic material. All aneurysms were obliterated successfully, with no adverse events. Each patient further received treatment of the AVM. None of the patients suffered intracranial haemorrhage after treatment for the aneurysms. Based on our experiences, we discuss the indications for this approach for each type of aneurysm. We believe endovascular treatment could be an important alternative for treatment of aneurysms associated with AVMs, thus reducing the risk of haemorrhage.
  • Mikuni N, Ikeda A, Murao K, Terada K, Nakahara I, Taki W, Kikuchi H, Shibasaki H
    EPILEPSIA 38(4) 472-482 1997年4月  査読有り
    Purpose. In presurgical evaluation of temporal lobe epilepsy (TLE), invasive methods are necessary if results of various noninvasive methods are not sufficiently convergent enough to identify the epileptogenic area accurately. To detect the epileptiform discharges originating specifically from the mesial temporal lobe, we applied the cavernous sinus catheterization technique. Methods: We placed Seeker Lite-10 guide wire electrodes into bilateral cavernous sinus through the internal jugular veins to record EEG (cavernous sinus EEG) in 6 patients with intractable TLE. Scalp EEG was simultaneously recorded in all 6 and electrocorticogram (ECoG) was also recorded in 4. Results: The cavernous sinus EEG demonstrated clear epileptiform discharges, sometimes even when they were absent on the simultaneously recorded scalp EEG. The epileptiform discharges recorded from the cavernous sinus electrodes were specifically associated with those in the mesial temporal region on ECoG. Ictal EEG pattern originating from mesial temporal lobe was also clearly documented on the cavernous sinus EEG. Conclusions: This new, semi-invasive method of identifying epileptogenic areas can detect the epileptiform discharges specifically arising from the mesial temporal lobe; it is as useful as or complements the invasive techniques such as foramen ovale or depth recording.
  • Tanaka F, Nishizawa S, Yonekura Y, Sadato N, Ishizu K, Okazawa H, Tamaki N, Nakahara I, Taki W, Konishi J
    EUROPEAN JOURNAL OF NUCLEAR MEDICINE 22(11) 1268-1273 1995年11月  査読有り
    Balloon test occlusion (BTO) of the internal carotid artery (ICA) combined with cerebral blood flow (CBF) study has proved to be a sensitive test for prediction of the outcome of permanent vessel occlusion, In this study, we evaluated the acute changes in regional CBF during BTO under hypotension in order to examine the possible risk of cerebral ischaemia after surgical treatment. Eleven patients in whom surgical carotid sacrifice was planned underwent BTO combined with CBF studies using technetium-99m hexamethyl-propylene amine oxime single-photon emission tomography under hypotension by decreasing the systemic blood pressure by about 50 mm Hg using a ganglion blocking agent, All patients showed a mild to severe decrease in CBF in the ipsilateral ICA territory relative to the contralateral side. A decrease in CBF of greater than 20% was observed in nine patients (82%), and two of them showed a decrease exceeding 40%, However, no ischaemic symptoms were demonstrated during scanning with hypotensive BTO. Our results suggest that in many patients with negative normotensive BTO, a considerable reduction in CBF would occur during hypotension, This procedure may predict a possible risk of hypotensive accident during and/or after surgery.
  • Nakahara I, Kikuchi H, Taki W, Nishi S, Kito M, Yonekawa Y, Goto Y, Ogata N
    JOURNAL OF NEUROSURGERY 76(2) 244-250 1992年2月  査読有り
    Major mitochondrial phosopholipids were examined in rat brain after 30 minutes of reperfusion following 30- or 60-minute periods of ischemia to examine their changes and explore their relationship to mitochondrial dysfunction during postischemic reperfusion. The amount of phospholipids and the percentage of polyunsaturated fatty acid chains, which tended to decrease during 30 minutes of ischemia, recovered after reperfusion. However, after ischemia lasting for 60 minutes, these parameters did not recover but decreased further, suggesting progressive disruption of phospholipids by phospholipase A2 after reperfusion. These changes were particularly notable in cardiolipin, which is contained specifically in mitochondria. The changes were also closely associated with mitochondrial respiration and respiratory enzyme (cytochrome c oxidase and F0F1-adenosine triphosphatase) activities, which have been known to correlate with the amount of cardiolipin. These results suggest that phospholipid metabolism in mitochondrial membranes is an important factor bearing on the integrity of energy metabolism during postischemic reperfusion.
  • Nakahara I, Kikuchi H, Taki W, Nishi S, Kito M, Yonekawa Y, Goto Y, Ogata N
    JOURNAL OF NEUROCHEMISTRY 57(3) 839-844 1991年9月  査読有り
    Changes in content of brain mitochondrial phospholipids were examined in rats after 30 and 60 min of decapitation ischemia compared with controls, to explore the degradation of the mitochondrial membrane and its relation to dysfunction of mitochondria. Activities of respiratory functions and respiratory enzymes (cytochrome c oxidase; F0F1-ATPase) decreased significantly during ischemia. Considerable decreases in cardiolipin and phosphatidylinositol content were observed after 60 min, and other phospholipids showed similar but nonsignificant decreases in content. The amount of polyunsaturated fatty acid chains, such as arachidonic and docosahexaenoic acids, was reduced in each phospholipid, in some cases significantly, after 30 and 60 min of ischemia in time-dependent manners. Degradation of mitochondrial phospholipids during ischemia associated with the deterioration of mitochondrial respiratory functions suggested the significance of such changes in phospholipid content in disintegration of cellular energy metabolism during cerebral ischemia.
  • Nakahara I, Taki W, Nishi S, Shibata O, Kikuchi H
    AMERICAN JOURNAL OF NEURORADIOLOGY 11(6) 1195-1197 1990年  査読有り
    Nakahara I, Taki W, Nishi S, Shibata O, Kikuchi H, AJNR. American journal of neuroradiology, 1990, vol. 11, no. 6, pp. 1195-1197

MISC

 186

主要な書籍等出版物

 8

共同研究・競争的資金等の研究課題

 4