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Featured researches published by Fumio Asakura.


World Neurosurgery | 2011

Determinants of Poor Outcome After Aneurysmal Subarachnoid Hemorrhage when both Clipping and Coiling Are Available: Prospective Registry of Subarachnoid Aneurysms Treatment (PRESAT) in Japan

Waro Taki; Nobuyuki Sakai; Hidenori Suzuki; Akio Hyodo; Shigeru Nemoto; Toshio Hyogo; Tomoaki Terada; K Satoh; Naoya Kuwayama; Shigeru Miyachi; Masaki Komiyama; Masayuki Ezura; Yuichi Murayama; Hiroshi Sakaida; Masayuki Maeda; H Nagai; T Kataoka; S Ishihara; Y Koguchi; S. Kobayashi; Y Enomoto; K Yamada; Shinichi Yoshimura; Yasushi Matsumoto; Masaru Hirohata; H Adachi; Y Ueno; T Kunieda; Chiaki Sakai; H Yamagami

OBJECTIVE To examine current determinants of poor outcome after aneurysmal subarachnoid hemorrhage (SAH) when ruptured aneurysms are treated with either microsurgery (clipping) or endovascular treatment (coiling) depending on each patients characteristics. METHODS Between March 2006 and February 2007, 534 patients with SAH were enrolled in the Prospective Registry of Subarachnoid Aneurysms Treatment (PRESAT) project. Patients were treated according to the preference of investigators who were experienced in performing both clipping and coiling. Factors influencing poor outcome (12-month modified Rankin Scale [mRS], 3-6) were determined using multivariate logistic regression analyses. RESULTS In this cohort, 32.4% of patients were World Federation of Neurosurgical Societies (WFNS) grade IV-V, and 28.1% had a poor outcome. Clipping was preferably performed for small aneurysms with a wide neck and for middle cerebral artery (MCA) aneurysms, whereas coiling was preferred for larger, internal carotid artery (ICA) and posterior circulation aneurysms. In addition to increasing age, admission WFNS grade IV-V, preadmission aneurysmal rerupture, vasospasm-induced cerebral infarct, pneumonia, sepsis, shunt-dependent hydrocephalus and seizure, postclipping hemorrhagic complications (odds ratio 4.8, 95% confidence interval 1.5-15.3, P < 0.01), and postcoiling ischemic complications (odds ratio 4.4, 95% confidence interval 1.3-15.2, P < 0.05) significantly caused poor outcomes, although the complications did not affect mortality. Type of treatment modality and size and location of aneurysms did not influence outcome. CONCLUSIONS Introducing an endovascular treatment option has made aneurysm characteristics less important to outcome, but procedural complications are problematic and should be reduced to improve outcome.


PLOS ONE | 2014

Inflammatory Biomarkers in Atherosclerosis: Pentraxin 3 Can Become a Novel Marker of Plaque Vulnerability

Akihiro Shindo; Hiroshi Tanemura; Kenichiro Yata; Kazuhide Hamada; Masunari Shibata; Yasuyuki Umeda; Fumio Asakura; Naoki Toma; Hiroshi Sakaida; Takao Fujisawa; Waro Taki; Hidekazu Tomimoto

Inflammation is crucially involved in the development of carotid plaques. We examined the relationship between plaque vulnerability and inflammatory biomarkers using intraoperative blood and tissue specimens. We examined 58 patients with carotid stenosis. Following carotid plaque magnetic resonance imaging, 41 patients underwent carotid artery stenting (CAS) and 17 underwent carotid endarterectomy (CEA). Blood samples were obtained from the femoral artery (systemic) and common carotid artery immediately before and after CAS (local). Seventeen resected CEA tissue samples were embedded in paraffin, and histopathological and immunohistochemical analyses for IL-6, IL-10, E-selectin, adiponectin, and pentraxin 3 (PTX3) were performed. Serum levels of IL-6, IL-1β, IL-10, TNFα, E-selectin, VCAM-1, adiponectin, hs-CRP, and PTX3 were measured by multiplex bead array system and ELISA. CAS-treated patients were classified as stable plaques (n = 21) and vulnerable plaques (n = 20). The vulnerable group showed upregulation of the proinflammatory cytokines (IL-6 and TNFα), endothelial activation markers (E-selectin and VCAM-1), and inflammation markers (hs-CRP and PTX3) and downregulation of the anti-inflammatory markers (adiponectin and IL-10). PTX3 levels in both systemic and intracarotid samples before and after CAS were higher in the vulnerable group than in the stable group. Immunohistochemical analysis demonstrated that IL-6 was localized to inflammatory cells in the vulnerable plaques, and PTX3 was observed in the endothelial and perivascular cells. Our findings reveal that carotid plaque vulnerability is modulated by the upregulation and downregulation of proinflammatory and anti-inflammatory factors, respectively. PTX3 may thus be a potential predictive marker of plaque vulnerability.


Surgical Neurology | 2008

Periprocedural hemodynamic instability with carotid angioplasty and stenting

Mahmoud M. Taha; Naoki Toma; Hiroshi Sakaida; Kotaro Hori; Masayuki Maeda; Fumio Asakura; Masashi Fujimoto; Satoshi Matsushima; Waro Taki

BACKGROUND Carotid angioplasty and stenting is used for treatment of carotid stenosis. Stent deployment may induce HDI and thereby cause systemic or neurologic deficits. This study defines characteristics and predictors of HDI with CAS. METHODS A total of 132 patients who had undergone CAS were evaluated for periprocedural and postprocedural HDI (hypertension, systolic blood pressure >160 mm Hg; hypotension, systolic blood pressure <90 mm Hg; or bradycardia, heart rate <60 beats per minute). RESULTS Frequencies of HDI were 6.8% for hypertension, 32.6% for hypotension, and 15.9% for bradycardia. In addition, CAS of the right side (P < .01), carotid bulb lesions (P < .05), eccentric posterior carotid plaque (P < .0001), and general anesthesia (P < .05) were associated significantly with postprocedural HDI. Male sex (OR, 3.4; 95% CI, 1.8-67.2; P < .001), age of 80 years or older (OR, 0.4; 95%CI, 0.1-1.4; P = .011), and plaque ulceration (OR, 0.5; 95% CI, 0.1-9.5; P = .008) independently predicted postprocedural hypertension. Male sex (OR, 2.5; 95% CI, 1.3-24.9; P < .001), preprocedural major stroke (OR, 0.1; 95% CI, 0.01-0.8; P = .002), carotid bulb lesions (OR, 1.6; 95% CI, 1.1-25.9; P = .024), and contralateral carotid occlusion (OR, 0.6; 95% CI, 0.2-4.9; P = .040) all predicted postprocedural hypotension. Bradycardia was associated with diabetes mellitus (OR, 0.7; 95% CI, 0.3-2.4; P = .033), preprocedural TIA (OR, 1.7; 95% CI, 1.4-17.9; P = .020), and minor stroke (OR, 1.5; 95% CI, 1-10.9; P = .037). In 5 patients, HDI predisposed neurologic or systemic deterioration. CONCLUSIONS Hemodynamic instability is common with CAS; hypotension and bradycardia are more frequent than hypertension. Some clinical, angiographic, and procedural variables can predict these HD changes.


Turkish Neurosurgery | 2010

Endovascular management of vertebral artery dissecting aneurysms: review of 25 patients.

Mahmoud M. Taha; Hiroshi Sakaida; Fumio Asakura; Masayuki Maeda; Naoki Toma; Akitaka Yamamoto; Kenji Kawaguchi; Satoshi Matsushima; Waro Taki

AIM Management of Vertebral Artery (VA) dissections remains controversial. The clinical and angiographic variables of VA dissections were evaluated to demonstrate the safety and efficacy of endovascular intervention in treatment of VA dissecting aneurysms. MATERIAL AND METHODS 25 patients with 27 VAdissecting aneurysms were treated with endovascular intervention during the last 10 years.17 patients were admitted with subarachnoid hemorrhage. 23 aneurysms treated using destructive endovascular trapping, while reconstructive techniques were used in 3 aneurysms treated with stent-assisted coiling and one aneurysm treated with false lumen embolization. RESULTS The right VA was involved in 14 patients, the left VA in 9 patients, while 2 patients had bilateral VA dissection. The pearl and string sign was the commonest angiographic sign in 12 aneurysms. Perioperative complications included; rebleeding in one patient, symptomatic brain stem infarction in two patients and silent cerebellar ischemic lesion in one patient. Afavorable outcome was evident more in patients with unruptured VA dissection (100%) versus (76.5%) in patients presented with SAH. CONCLUSION The endovascular technique should be individualized according to the clinical status of the patient, angiographic variables, condition of the posterior circulation and the available supplies.


Surgical Neurology | 2003

Evaluation of intra-aneurysmal blood flow by digital subtraction angiography: blood flow change after coil embolization

Fumio Asakura; Hiroshi Tenjin; Noriaki Sugawa; Satoshi Kimura; Fumiya Oki

BACKGROUND The natural course of cerebral aneurysms is related to many factors, and it is very important that intra-aneurysmal blood flow is considered. Our group developed a method that allowed the simultaneous evaluation of blood flow in human cerebral aneurysms using digital subtraction angiography (DSA) with no special devices. The intra-aneurysmal blood flow measurement would also be very useful for coil embolization. Since the Guglielmi detachable coil (GDC) was developed, many patients with cerebral aneurysm have been treated with GDC, but coil compaction has sometimes caused a problem after the coil embolization of a cerebral aneurysm. We believed that an intra-aneurysmal flow measurement would suggest the final result of embolization during the procedure. METHODS We performed DSA to examine 17 aneurysms in 17 patients. The video signal of serial DSA images was stored on a personal computer, and time-density curves were obtained for each individual pixel. The formula, determined by a two-exponential model, was fitted to the time-density curve 1000 times by least square approximation for each individual pixel. We indirectly substituted the coefficient of the flow-in curve for the blood flow. We were therefore able to display the distribution of intra-aneurysmal blood flow in color. We could compare the blood flow in each portion of the cerebral aneurysm and parent artery during coil embolization. RESULTS The blood flow k(a) in a small aneurysm was faster than that in a large aneurysm, and it slowed in accordance with the coil embolization. The blood flow in a large aneurysm was sometimes accelerated by incomplete coil embolization. CONCLUSION We can detect the flow distribution in cerebral aneurysms and the flow change during coil embolization, using existing equipment. Our method would be useful in elucidating the natural history of cerebral aneurysms, treating cerebral aneurysms with coils, and following patients after treatment.


Stroke | 2013

High-Risk Plaque for Carotid Artery Stenting Evaluated With 3-Dimensional T1-Weighted Gradient Echo Sequence

Hiroshi Tanemura; Masayuki Maeda; Naoki Ichikawa; Yoichi Miura; Yasuyuki Umeda; Seiji Hatazaki; Naoki Toma; Fumio Asakura; Hidenori Suzuki; Hiroshi Sakaida; Satoshi Matsushima; Waro Taki

Background and Purpose— Preventing cerebral embolisms is a major concern with carotid artery stenting (CAS). This study evaluated 3-dimensional T1-weighted gradient echo (3D T1GRE) sequence to predict cerebral embolism related to CAS. Methods— We performed quantitative analyses of the characteristics of 47 carotid plaques before CAS by measuring the signal intensity ratio (SIR) and plaque volume using 3D T1GRE images. We used T1-weighted turbo field echo sequence to obtain 3D T1GRE images. We also evaluated diffusion-weighted images (DWI) of the brain before and after CAS to detect ischemic lesions (DWI lesions) from cerebral emboli. Results— SIR (2.17 [interquartile range 1.50–3.07] versus 1.35 [interquartile range 1.08–1.97]; P=0.010) and plaque volume (456 mm3 [interquartile range 256–696] versus 301 mm3 [interquartile range 126–433]; P=0.008) were significantly higher in the group of patients positive for DWI lesions (P-group: n=26) than DWI lesion-negative patients (N-group: n=21). In multivariate logistic regression analysis, SIR (P=0.007) and plaque volume (P=0.042) were independent predictors of DWI lesions with CAS. Furthermore, SIR (rs=0.42, P=0.005) and plaque volume (rs=0.36, P=0.012) were positively correlated with the number of DWI lesions. From analysis of a receiver-operating characteristic curve, the most reliable cutoff values of SIR and plaque volume to predict DWI lesions related to CAS were 1.80 and 373 mm3, respectively. Conclusions— Quantitative evaluation of carotid plaques using 3D T1GRE images may be useful in predicting cerebral embolism related to CAS.


Interventional Neuroradiology | 2011

Combination of Rare Right Arterial Variation with Anomalous Origins of the Vertebral Artery, Aberrant Subclavian Artery and Persistent Trigeminal Artery: A Case Report

H. Ishihara; D. San Millán Ruíz; German Abdo; Fumio Asakura; Hasan Yilmaz; Karl-Olof Lövblad; Daniel A. Rüfenacht

A 32-year-old woman hospitalized for subarachnoid hemorrhage showed rare arterial variation on the right side with anomalous origins of the vertebral artery, aberrant subclavian artery and persistent trigeminal artery. Angiography showed the right vertebral artery to originate from the right common carotid artery, the right subclavian artery to arise separately from the descending aorta, and persistent trigeminal artery on the right side. The possible embryonic mechanism of this previously unreported variant combination is discussed.


NMC Case Report Journal | 2018

Tiny Falx Meningioma Causing Massive Interhemispheric Subdural Hematoma: A Case Report

Yume Suzuki; Masashi Fujimoto; Fumihiro Kawakita; Fumio Asakura; Hiroto Murata; Yoshito Morooka; Hidenori Suzuki

Bleeding from meningiomas is well known, but massive subdural hemorrhage from a very small meningioma is rare. A 61-year-old woman presented with a sudden-onset headache and slight right hemiparesis without a history of trauma. Computed tomographic scan showed bilateral acute/subacute interhemispheric subdural hematoma, but contrast-enhanced computed tomography (CT) scan, non-enhanced magnetic resonance imaging (MRI) and digital subtraction angiography failed to detect the cause. The hematoma was conservatively treated. Three weeks later, CT scans showed a vestige of the hematoma along the falx. However, repeated angiogram revealed a tumor stain on the falx supplied by the middle meningeal arteries, leading to the tentative diagnosis of meningioma. The tumor was removed and histologically diagnosed as angiomatous meningioma. It is rare that falx meningioma causes massive interhemispheric subdural hematoma, and the diagnosis of the causative lesion is challenging if tumor is small. We review the literature and discuss the characteristics.


Journal of Biomedical Materials Research Part B | 2010

Simple immersion of filter devices into an urokinase solution prevents fibrin net formation during carotid artery stenting

Kazuhide Hamada; Satoshi Matsushima; Naoki Toma; Takahiko Totani; Mitsuaki Toda; Satoru Ogawa; Fumio Asakura; Hiroshi Sakaida; Hiroo Iwata; Waro Taki

Slow-flow phenomenon is frequently observed during carotid artery stenting (CAS) with a filter embolic protection device. It results in technical difficulties and can lead to adverse neurological events. Flow impairment is thought to be caused by plaque entrapped by the filter and/or blood coagulation on the filter. Characteristics of heparin- or urokinase-treated polyurethanes were analyzed by surface plasmon resonance, and the fibrinolytic activity of the urokinase-treated filter of Angioguard XP was estimated by the fibrin plate assay. A filter membrane of Angioguard XP protection device was treated with a heparin or urokinase solution. In clinical studies, six and nine patients were treated by CAS using Angioguard XP modified with heparin and urokinase, respectively. Filter membranes were examined by scanning electron microscopy (SEM). From in vitro studies, it appeared that urokinase adsorbed and remained on the Angioguard XP filter, and its fibrinolytic activity was demonstrated even after washing with saline; heparin, however, was easily washed out from the surface. From clinical study, some filter pores were obstructed in all six patients in the heparin group and in three patients in the urokinase group. Fibrin net was found on the filter in five of six patients in the heparin group and in one of nine patients in the urokinase group. Treatment of an Angioguard XP filter with a urokinase solution is effective in preventing pore occlusion and may reduce occurrence of the slow-flow phenomenon.


Neuroradiology | 2006

Diffusion-weighted magnetic resonance imaging in carotid angioplasty and stenting with balloon embolic protection devices

Fumio Asakura; Kenji Kawaguchi; Hiroshi Sakaida; Naoki Toma; Satoshi Matsushima; Keita Kuraishi; Hiroshi Tanemura; Yoichi Miura; Masayuki Maeda; Waro Taki

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