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Dive into the research topics where Yoshitaka Kubo is active.

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Featured researches published by Yoshitaka Kubo.


Surgical Neurology | 2008

Serum inflammatory adhesion molecules and high-sensitivity C-reactive protein correlates with delayed ischemic neurologic deficits after subarachnoid hemorrhage

Yoshitaka Kubo; Kuniaki Ogasawara; Shunsuke Kakino; Hiroshi Kashimura; Nobuhiko Tomitsuka; Atsushi Sugawara; Akira Ogawa

BACKGROUND The purpose of the present study was to investigate the relationship between serum concentrations of the immunoglobulin-like superfamily, selectins, hsCRP, and the development of DIND in patients with aneurysmal SAH. METHODS Serum ICAM-1, VCAM-1, E-selectin, P-selectin, L-selectin, and hsCRP were measured in 33 patients with SAH who underwent aneurysmal clipping within 48 hours of the onset of symptoms. Serum samples were obtained during the early period (day 0) and the late period (day 7). RESULTS The serum concentrations of ICAM-1 (P = .009), VCAM-1 (P = .0383) and hsCRP (P = .0014) during the early period were significantly higher in patients with SAH than in control patients. Further, serum hsCRP concentration during the late period was significantly higher in patients with SAH than in control patients (P = 0033). Finally, serum concentrations of ICAM-1, VCAM-1, and hsCRP during the early (P = .0055, P = .0266, and P = .0266) and late (P = .0423, P = .0041, and P = .0004) period were significantly higher in patients with DIND than in patients without DIND. CONCLUSIONS Serum levels of ICAM-1, VCAM-1 and hsCRP during the early and late period following SAH correlate with DIND.


Neurosurgery | 2006

Revascularization and parent artery occlusion for giant internal carotid artery aneurysms in the intracavernous portion using intraoperative monitoring of cerebral hemodynamics

Yoshitaka Kubo; Kuniaki Ogasawara; Nobuhiko Tomitsuka; Yasunari Otawara; Shunsuke Kakino; Akira Ogawa

OBJECTIVE:Therapeutic parent artery occlusion with or without revascularization is a useful surgical technique for the management of a giant aneurysm located in the intracavernous portion of the internal carotid artery (ICA). The purpose of the present study was to determine whether intraoperative cortical blood flow (CoBF) monitoring during surgical parent artery occlusion could identify patients who required bypass with a saphenous vein graft (high flow bypass). METHODS:Eleven patients with a giant aneurysm located in the intracavernous portion of the ICA underwent superficial temporal artery-middle cerebral artery bypass. CoBF was monitored intraoperatively in all patients using a thermal diffusion flow probe. The lowest CoBF during test occlusion of the ICA under functioning superficial temporal artery-middle cerebral artery bypass was determined, and the ratio of the value to the CoBF immediately before test occlusion of the ICA was calculated in the frontal and temporal lobes. When the CoBF ratio in the frontal or temporal lobe was less than 0.9, high flow bypass grafting was elected. RESULTS:Of the eleven patients undergoing superficial temporal artery-middle cerebral artery bypass, five patients underwent concomitant high flow bypass grafting. Postoperative cerebral ischemic events did not occur in any patient over a follow-up period ranging from 3 to 60 months. Postoperative cerebral angiography showed resolution of the aneurysm and patency of the bypass in all patients. CONCLUSION:Intraoperative CoBF monitoring using a thermal diffusion flow probe during surgical parent artery occlusion for giant intracavernous carotid artery aneurysms can identify patients who require concomitant high flow bypass grafting.


Neurosurgical Review | 1998

Development of a dissecting aneurysm on the vertebral artery immediately after occlusion of the contralateral vertebral artery: A case report

Yoshitaka Kubo; Kazuyuki Miura; Michiyasu Suzuki; Kou Tsuiki; Noriyuki Kuwata; Naohiko Kubo; Kiyoshi Kuroda; Akira Ogawa

A 49 year old female presented with subarachnoid hemorrhage due to a ruptured dissecting aneurysm on the left vertebral artery (VA). Following an occlusion test, we performed proximal occlusion of the left VA with detachable balloons. However, a dissecting aneurysm on the right VA developed three weeks later. After an occlusion test had showed no change in cerebral blood flow, auditory brain stem response, or neurological status, proximal occlusion of the right VA was performed. The patient has returned to normal life without neurological deficits. Bilateral dissecting aneurysms of the VA are quite common, but de novo VA dissecting aneurysms or enlargement of such aneurysms after occlusion of contralateral VA are rare. This case suggests that hemodynamic stress may be a causal factor in the development of VA dissecting aneurysms. Careful pre- and post-operative neuroradiological examination of the contralateral VA are required in patients under-going VA occlusion for dissecting aneurysms.


American Journal of Neuroradiology | 2013

Postoperative Changes in Cerebral Metabolites Associated with Cognitive Improvement and Impairment after Carotid Endarterectomy: A 3T Proton MR Spectroscopy Study

Hideo Saito; Kuniaki Ogasawara; Hideaki Nishimoto; Yoshichika Yoshioka; Toshiyuki Murakami; Shunro Fujiwara; Makoto Sasaki; Masakazu Kobayashi; Kenji Yoshida; Yoshitaka Kubo; Takaaki Beppu; Akira Ogawa

This study assessed the use of metabolites seen on MRS as markers of change in cognitive status after carotid artery surgery. MRS and neurocognitive testing were obtained before and after surgery in 100 patients. The results showed that cognition remained unchanged in 80%, improved in 10%, and was impaired in 10% of patients postoperatively and that in these last 2 groups, NAA/Cr correlated well the clinical status. Thus, NAA/Cr may serve as a marker of neurologic status after carotid artery surgery (see accompanying editorial by Lövblad and Pereira). BACKGROUND AND PURPOSE: Cognitive function can improve or decline after carotid endarterectomy. Proton MR spectroscopy can be used evaluate cerebral metabolites, such as N-acetylaspartate, choline, and creatine, in vivo. The purpose of the present study was to determine whether postoperative changes in cerebral metabolites measured by using 3T proton MR spectroscopy were associated with changes in cognitive function after CEA. MATERIALS AND METHODS: In 100 patients undergoing CEA for ipsilateral cervical internal carotid artery stenosis (≥70%), brain proton MR spectroscopy was performed before and after surgery. NAA/Cr and Cho/Cr ratios were measured in regions of interest placed in the centrum semiovale of both cerebral hemispheres. Neuropsychological testing was also performed preoperatively and 1 month postoperatively. Multivariate statistical analysis of factors related to postoperatively changed cognition was performed, and odds ratios with 95% confidence intervals were calculated. RESULTS: On the basis of the neuropsychological assessments, 10 (10%), 80 (80%), and 10 (10%) patients were defined as having postoperatively improved, unchanged, and impaired cognition, respectively. A positive and high ΔNAA/Cr ratio (postoperative value–preoperative value) in the cerebral hemisphere ipsilateral to the operative site was significantly associated with postoperatively improved cognition (95% CI, 13.3–21.3; P = .0016). Negative and high absolute values of the ΔNAA/Cr ratio (95% CI, 0.018–0.101; P = .0039) and ΔCho/Cr ratio (95% CI, 0.042–0.135; P = .0046) in the ipsilateral cerebral hemisphere were significantly associated with postoperatively impaired cognition. CONCLUSIONS: Postoperative changes in cerebral metabolites measured by using proton MR spectroscopy were associated with changes in cognitive function after CEA.


World Neurosurgery | 2010

Cognitive function and anxiety before and after surgery for asymptomatic unruptured intracranial aneurysms in elderly patients.

Yoshitaka Kubo; Kuniaki Ogasawara; Hiroshi Kashimura; Yasunari Otawara; Shunsuke Kakino; Atsushi Sugawara; Akira Ogawa

BACKGROUND The prevalence of patients with asymptomatic unruptured intracranial aneurysms (UIAs) will likely increase as the general population ages. The goal of the present study was to prospectively assess cognitive function and anxiety before and after surgical repair of asymptomatic UIAs in patients ≥ 70 years. METHODS A total of 28 patients ≥ 70 years with UIAs underwent cognitive testing using the Wechsler Adult Intelligence Scale-Revised, Wechsler Memory Scale (WMS), and the Rey-Osterrieth Complex Figure test (ROCF) 1 month before and 1 month after surgery. All patients also underwent anxiety testing at these time points using the State-Trait Anxiety Inventory. RESULTS Group-rate analysis demonstrated that the performance intelligence quotient (IQ) and ROCF recall trial scores were significantly increased postoperatively, whereas there were no postoperative differences in verbal IQ, WMS, and ROCF copy trial scores. State anxiety scores were significantly decreased postoperatively, but there was no change in trait anxiety scores. Furthermore, a significant negative correlation was observed between changes in state anxiety scores and preoperative verbal IQ, performance IQ, and WMS. None of the patients developed postoperative cognitive functional impairments as demonstrated by event-rate analysis. CONCLUSIONS Surgical treatment of UIAs does not impair cognitive function and results in improvement in state anxiety in elderly patients.


Journal of Neurosurgery | 2014

Female sex as a risk factor for the growth of asymptomatic unruptured cerebral saccular aneurysms in elderly patients

Yoshitaka Kubo; Takahiro Koji; Hiroshi Kashimura; Yasunari Otawara; Akira Ogawa; Kuniaki Ogasawara

OBJECT The prevalence of patients with asymptomatic unruptured intracranial aneurysms (UIAs) increases with the advancing age of the general population. The goal of the present study was to identify risk factors for the growth of UIAs detected with serial MR angiography (MRA) in patients 70 years of age or older. METHODS This prospective study enrolled 79 patients (age range 70-84 years) with 98 UIAs. Patients were followed up every 4 months, including an assessment of the aneurysm diameter and morphological changes on MRA, neurological status, and other medical conditions. Aneurysm growth was categorized into two different patterns on the basis of the MRA findings: 1) maximum increase in aneurysm diameter of 2 mm or more; and 2) obvious morphological change, such as the appearance of a bleb. RESULTS The mean duration of follow-up was 38.5 months (250.2 patient-years). Aneurysm rupture did not occur, but aneurysm growth was observed in 8 aneurysms (8 patients) during the study period. Univariate analysis showed that female sex, patient age ≥ 75 years, and an aneurysm location in the internal carotid artery (ICA) or middle cerebral artery (MCA) were associated with aneurysm growth (p = 0.04, p = 0.04, and p < 0.001, respectively). Multivariate analysis demonstrated that female sex was the only independent predictor of aneurysm growth (p = 0.0313, OR 2.3, 95% CI 1.3-30.2). CONCLUSIONS Female sex is an independent risk factor for the growth of UIAs in elderly patients. In addition, an age ≥ 75 years and aneurysm location in the ICA or MCA are characteristics that may warrant additional attention during follow-up imaging.


Cerebrovascular Diseases | 2008

Cerebrospinal fluid adrenomedullin concentration correlates with hyponatremia and delayed ischemic neurological deficits after subarachnoid hemorrhage.

Yoshitaka Kubo; Kuniaki Ogasawara; Shunsuke Kakino; Hiroshi Kashimura; Kenji Yoshida; Akira Ogawa

Background: Adrenomedullin (AM), a vasorelaxant peptide, is secreted into the cerebrospinal fluid (CSF) from the choroid plexus and can exert natriuretic effects in the kidney. CSF AM concentration is elevated 7–10 days after the onset of aneurysmal subarachnoid hemorrhage (SAH). The aim of the present study was to determine whether CSF AM concentrations correlate with hyponatremia and delayed ischemic neurological deficits (DIND) after SAH. Methods: CSF and plasma concentrations of AM, brain natriuretic peptide, and atrial natriuretic peptide concentrations were measured in 32 patients with SAH who underwent aneurysmal clipping within 48 h of onset. CSF and blood samples were obtained from these patients during the early period (days 1–3, day 0 being regarded as the day of SAH onset) and the late period (days 8–10). Results: In all patients, AM concentration during the early and late periods was significantly higher in the CSF than in the plasma (p = 0.0028 and p < 0.0001). In addition, CSF AM concentration was significantly higher during the late period than during the early period (p < 0.0001). Hyponatremia (plasma sodium <135 mmol/l) was present in 11 patients (34.4%) during the late period, and DIND developed in 6 patients (19%) between day 5 and day 13. Logistic regression analysis demonstrated that late-period CSF AM concentration correlated with hyponatremia and DIND (95% CI: 1.003–1.069, p = 0.0074 and 95% CI: 1.003–1.052, p = 0.0108). Conclusions: The present study demonstrated that CSF AM during the late period following SAH correlates with hyponatremia and DIND.


Brain Tumor Pathology | 1998

Pathological analyses of early recurrence and malignant transformation in meningiomas

Hiroshi Arai; Takaaki Beppu; Tukasa Wada; Yuuki Yoshida; Yoshitaka Kubo; Michiyasu Suzuki; Akira Ogawa

We investigated factors of the early recurrence and malignant transformation of histologically benign meningiomas using immunohistochemistry for MIB-1 positive indices (PI) and p53 protein expression, a flow cytometric DNA analysis, and the examination of numerical chromosomal aberrations detected by fluorescence in situ hybridization using an α-satellite DNA probe and abcr gene locus-specific probe. Twenty-six meningiomas of 23 patients were classified into two groups: the 3 patients in whom a recurrence was defined within two years after initial surgery and who showed histologically malignant features were classified as the early recurrent group, and the other 20 patients in whom recurrence did not develop during the same period were classified as the nonrecurrent group. DNA aneuploidy was observed in 40% of the nonrecurrent patients and in 67% of the early recurrent patients. Loss of chromosome 22 was the most common numerical aberration, but the aberrations characteristic of early recurrent meningiomas were not detected. The MIB-1 PI values of the early recurrent meningiomas were higher than those of nonrecurrent meningiomas, suggesting that MIB-1 PI is very important for biological and histopathological analyses and prediction of the future recurrence of meningiomas.


Neurosurgery | 2013

Postoperative increase in cerebral white matter fractional anisotropy on diffusion tensor magnetic resonance imaging is associated with cognitive improvement after uncomplicated carotid endarterectomy: tract-based spatial statistics analysis.

Yuiko Sato; Kenji Ito; Kuniaki Ogasawara; Makoto Sasaki; Kohsuke Kudo; Toshiyuki Murakami; Takamasa Nanba; Hideaki Nishimoto; Kenji Yoshida; Masakazu Kobayashi; Yoshitaka Kubo; Tomohiko Mase; Akira Ogawa

BACKGROUND Carotid endarterectomy (CEA) might improve cognitive function. Fractional anisotropy (FA) values in the cerebral white matter derived from diffusion tensor magnetic resonance imaging (DTI) correlate with cognitive function in patients with various central nervous system diseases. OBJECTIVE To use tract-based spatial statistics to determine whether postoperative changes of FA values in the cerebral white matter derived from DTI are associated with cognitive improvement after uncomplicated CEA. METHODS In 80 patients undergoing CEA for ipsilateral internal carotid artery stenosis (≥70%), FA values in the cerebral white matter were derived from DTI before and 1 month after surgery and were analyzed by using tract-based spatial statistics. Neuropsychological testing, consisting of the Wechsler Adult Intelligence Scale Revised, the Wechsler Memory Scale and the Rey-Osterreith Complex Figure test, was also performed preoperatively and after the first postoperative month. RESULTS Based on the neuropsychological assessments, 11 (14%) patients were defined as having postoperatively improved cognition. The difference between the 2 mean FA values (postoperative values minus preoperative values) in the cerebral hemisphere ipsilateral to surgery was significantly associated with postoperative cognitive improvement (95% confidence intervals, 2.632-9.877; P = .008). White matter FA values in patients with postoperative cognitive improvement were significantly increased after surgery in the whole ipsilateral cerebral hemisphere, in the contralateral anterior cerebral artery territory, and in the watershed zone between the contralateral anterior and middle cerebral arteries. CONCLUSION Postoperative increase in cerebral white matter FA on DTI is associated with cognitive improvement after uncomplicated CEA.


Surgical Neurology | 2009

Comparison of postoperative cognitive function in patients undergoing surgery for ruptured and unruptured intracranial aneurysm

Yasunari Otawara; Kuniaki Ogasawara; Yoshitaka Kubo; Hiroshi Kashimura; Akira Ogawa; Keiko Yamadate

BACKGROUND Patients with SAH often experience cognitive decline. Previous studies used normal volunteers, published normal test values, and orthopedic patients as controls to identify factors for postoperative cognitive decline. The present study excluded the effects of surgery by comparing cognitive function after surgical repair in patients with aneurysmal SAH and patients with unruptured intracranial aneurysm. METHODS This study recruited 117 patients with SAH due to ruptured aneurysm and 39 patients with incidentally found unruptured intracranial aneurysms. The cognitive test battery consisted of the Japanese translation of the WAIS-R, the Japanese translation of the WMS, and the recall trial of the ROCF. Postoperative neuropsychological test scores for the patients with SAH and control subjects were compared using group-rate and event-rate analysis. The relationship between clinical variable and postoperative cognitive decline in the patients with SAH was evaluated by univariate analysis using the Mann-Whitney U test or chi(2) test. RESULTS Group-rate analysis showed that the WAIS-R and ROCF scores were significantly lower in the SAH group than in the control group. Event-rate analysis demonstrated that the incidence of cognitive decline in the patients with SAH (73 [62.4%] of the 117 patients) was significantly higher than that in the control subjects (12 [30.8%] of 39 patients). The Hunt and Hess grade was significantly higher in patients with postoperative cognitive decline. CONCLUSION The cognitive function after SAH was significantly correlated with Hunt and Hess grade on admission when using patients with postoperative unruptured intracranial aneurysm as the control group.

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Akira Ogawa

Iwate Medical University

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Kenji Yoshida

Iwate Medical University

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