Satoshi Iwabuchi
Toho University
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Featured researches published by Satoshi Iwabuchi.
Neuroscience Letters | 2005
Yoko Hirata; Hiroshi Matsuda; Kiyotaka Nemoto; Takashi Ohnishi; Kentaro Hirao; Fumio Yamashita; Takashi Asada; Satoshi Iwabuchi; Hirotsugu Samejima
We assessed the accuracy of voxel-based morphometry (VBM) using a three-dimensional T1-weighted MRI in discriminating Alzheimers disease (AD) in the very early stage of amnestic type of mild cognitive impairment and age-matched healthy controls. We randomly divided these subjects into two groups. The first group comprising 30 AD patients and 41 controls was used to identify the area with the most significant gray matter loss in patients compared to normal controls based on the voxel-based analysis of a group comparison. The second group comprising 31 patients and 41 controls was used to determine the discrimination accuracy of VBM. A Z-score map for a gray matter image of a subject was obtained by comparison with mean and standard deviation gray matter images of the controls for each voxel after anatomical standardization and voxel normalization to global mean using the following equation; Z-score=([control mean]-[individual value])/(control S.D.). Receiver operating characteristic curves for a Z-score in the bilateral medial temporal areas including the entorhinal cortex with the most significant loss in the first group showed a high discrimination accuracy of 87.8%. This result would open up a possibility for early diagnosis of AD using VBM.
Medical Mycology | 2007
Katsuji Taguchi; Toshiaki Oharaseki; Yuki Yokouchi; Tomoko Kawabata; Megumi Wakayama; Toshio Ogoshi; Satoshi Iwabuchi; Kazutoshi Shibuya; Kazuko Nishimura; Kei Takahashi
There have been very few reports in Japan of patients with allergic fungal sinusitis (AFS). We describe two cases caused by Bipolaris spicifera and Schizophyllum commune. The patients were a 70-year-old male (Case 1) and a 55-year-old female (Case 2). Both presented with nasal obstruction and purulent nasal discharge. CT scans revealed each to have a soft tissue mass extending from the ethmoid sinus to the sphenoid sinus. In addition, pathological studies on the contents of the paranasal sinuses of both patients revealed the presence of fungal elements in the allergic mucin. Microbiological studies resulted in the recovery of Bipolaris spicifera from Case 1 and Schizophyllum commune from Case 2. To date there have been no reports of AFS due to these two fungi in Japan. It is very important in the diagnosis of AFS to demonstrate the presence of fungal elements in the allergic mucin. Squash cytology of the paranasal sinus contents was especially useful for proving the presence of fungi.
International Journal of Experimental Pathology | 2007
Norihiko Saito; Tsutomu Hatori; Nozomu Murata; Zean Zhang; Hiroko Nonaka; Kazuya Aoki; Satoshi Iwabuchi; Morikazu Ueda
As methods of cancer diagnosis and treatment progress, interest in metastatic brain tumours continues to increase. There are many studies using various methods of animal model and we considered that each model reflects different pathological processes because of the unique composition of the brain. We prepared metastatic brain tumour models using three different methods. In this study, we attempted to elucidate the roles of the pia mater in brain metastasis. The metastatic foci showed an angiocentric pattern, forming collars of neoplastic cells, and were designated ‘perivascular proliferations’. Furthermore, we observed neoplastic cells that infiltrated the brain parenchyma, the border of which had become indistinct. These were labelled ‘invasive proliferations’. The internal carotid artery injection model reflects haematogenous metastasis. In this model, both perivascular and invasive proliferations were observed. The intrathecal injection model reflects leptomeningeal carcinomatosis. In this model, metastasis to the meninges was observed. In the stereotactic injection model, the tumour proliferation at the injection site and the infiltration into the brain parenchyma were observed. The pia‐glial membrane serves as a scaffold when neoplastic cells spread to the perivascular space forming angiocentric pattern. The pia‐glial membrane is found between the brain parenchyma and blood vessels. Blood vessels penetrate the brain through tunnels known as perivascular spaces that are covered by pia mater. Three different methods which we prepared reflect three different pathological processes. Our findings suggest that the pia mater is a critical factor in brain metastasis.
Acta neurochirurgica | 2011
Satoshi Iwabuchi; Tetsuya Yokouchi; Morito Hayashi; Kenichiro Sato; Norihiko Saito; Y. Hirata; Junichi Harashina; Haruo Nakayama; Masaki Akahata; Keisuke Ito; Hitoshi Kimura; Kazuya Aoki
BACKGROUND we investigated the clinical efficacy of intra-arterial administration of fasudil hydrochloride for cerebral vasospasm. METHOD we reviewed 90 cases treated with intra-arterial administration of fasudil hydrochloride between August 1998 and April 2009 and investigated the clinical efficacy for cerebral vasospasm. FINDINGS angiographic improvement of vasospasm was noted in all procedures. Eight had ischemic lesion on CT at discharge in Group A, which included 39 patients who presented angiographic and symptomatic vasospasm. However, 4 (50%) of these eight were recovered with a condition of GR. No patients showed ischemic lesion on CT in Group B, which included 51 patients who presented angiographic vasospasm without symptoms. Two (3.3%) of 59 patients who presented angiographic vasospasm without symptoms at the initial follow-up angiography had ischemic lesion on CT at discharge. The 1-year follow-up showed 78.9% of GR. No patient showed any adverse effects resulting from intra-arterial administration of fasudil hydrochloride. CONCLUSION intra-arterial administration of fasudil hydrochloride was an effective and safe management technique for vasospasm.
Journal of Ophthalmology | 2016
Masashi Ishii; Morito Hayashi; Fumihiko Yagi; Kenichiro Sato; Goji Tomita; Satoshi Iwabuchi
When internal carotid artery stenosis is accompanied by ocular ischemic syndrome, intervention is recommended to prevent irreversible visual loss. In this study, we used laser speckle flowgraphy to measure the ocular microcirculation in the optic nerve head before and after carotid artery stenting (CAS) of 40 advanced internal carotid stenosis lesions from 37 patients. The aim was to investigate the relationship between ocular microcirculation and the direction of ophthalmic artery blood flow obtained by angiography. We found that there was a significant increase in blood flow after CAS (P = 0.003). Peak systolic velocity as an indicator of the rate of stenosis was also significantly higher in the group with retrograde/undetected flow of the ophthalmic artery than in the group with antegrade flow (P = 0.002). In all cases where retrograde flow of the ophthalmic artery was observed before stenting, the flow changed to antegrade after stenting. Through the use of laser speckle flowgraphy, this study found that CAS can improve ocular microcirculation. Furthermore, while patients displaying retrograde flow of the ophthalmic artery before stenting have a poor prognosis, CAS corrected the flow to antegrade, suggesting that visual loss can be prevented by improving the ocular microcirculation.
Neuropathology | 2009
Norihiko Saito; Tsutomu Hatori; Kazuya Aoki; Morito Hayashi; Yoko Hirata; Kenichiro Sato; Haruo Nakayama; Junichi Harashina; Nozomu Murata; Zean Zhang; Hiroko Nonaka; Kazutoshi Shibuya; Satoshi Iwabuchi
As methods of cancer diagnosis and treatment improve, interest in metastatic brain tumors continues to increase. In the present study, we attempted to characterize genetically the dynamic changes occurring during brain metastasis formation by DNA microarray, and attempted to compare these findings with histological observations. Lewis lung carcinoma cells were injected into C57BL/6Ncrj mice carotid arteries. The mice were sacrificed at days 1–9 after injection. We performed histological observation and genome‐wide expression profiling using a DNA microarray. In histological observation, tumor cells were observed in capillary vessels at day 1 after injection. At day 3, the tumor cells had begun to proliferate. At day 6, the metastatic foci showed “perivascular proliferations”. Next, we performed a pairwise comparison of gene expression microarray data from day 1 to day 9 after injection. The first major change occurred between Phase Two and Phase Three. When hierarchical clustering was performed between different samples using the 867 genes, they could be classified into identical clusters for days 1 and 2, identical clusters for day 3 to day 5, and identical clusters for day 6 to day 9. For time course analysis, we extracted 623 genes by the pairwise comparison. By using the quality threshold (QT) nonhierarchical clustering method, we identified 37 expression patterns. These patterns can be separated into eight clusters by using the k‐means method. The microarray results reported here strongly suggest that a large number of genes exhibit a spike pattern, which is tantamount to phase‐specific expression.
Acta neurochirurgica | 2015
Satoshi Iwabuchi; Morito Hayashi; Tetsuya Yokouchi; Kenichiro Sato; Haruo Nakayama; Junichi Harashina; Junya Iwama; Masashi Ishii; Yu Hiramoto; Nozomi Hirai; Y. Hirata; Norihiko Saito; Keisuke Ito; Hitoshi Kimura; Kazuya Aoki
PURPOSE We evaluated patients treated with prophylactic intra-arterial administration of fasudil hydrochloride (IAF) after subarachnoid haemorrhage (SAH). MATERIALS AND METHODS Between August 1998 and December 2012, 92 patients with aneurysmal SAH were treated with IAF for angiographic vasospasm without ischemic symptoms after their follow-up angiography. Patients comprised 50 women and 42 men, aged 24-83 (mean 56.6) years. IAF consisted of 15 mg of fasudil hydrochloride dissolved in 20 ml physiological saline and injected through a catheter during approximately 15 min, after diagnostic angiography. The clinical outcome was evaluated using the Glasgow Outcome Scale (GOS) at discharge and ischemic lesions resulting from vasospasm were assessed on computed tomography (CT) scan at discharge. RESULTS Forty-eight patients underwent surgical clipping and 44 patients underwent endovascular coiling. Angiographic improvement was observed in all patients (100 %). At discharge, 76 (83.0 %) of 92 patients showed good recovery on GOS. Nine patients developed progression of delayed ischemic neurological deficits (DIND) and three of these patients had ischemic lesions on CT scans. No patient had any significant changes in vital signs or any other adverse effects resulting from IAF. CONCLUSION IAF therapy was safe and effective for patients with vasospasm following SAH. Prophylactic IAF therapy may prevent symptomatic vasospasm.
Case Reports in Medicine | 2011
Arata Tomiyama; Kazuya Aoki; Haruo Nakayama; Hideaki Izukura; Hitoshi Kimura; Junichi Harashina; Keisuke Ito; Morito Hayashi; Norihiko Saito; Takatoshi Sakurai; Toshiaki Oharaseki; Hitoshi Terada; Satoshi Iwabuchi
A 14-year-old was girl admitted to our hospital with a subcutaneous mass of the occipital head. The mass had grown for 6 years, after she had sustained a head injury at the age of 6, and was located directly under a previous wound. Skull X-ray Photograph (xp), computed tomography (CT), and magnetic resonance imaging (MRI) showed a bony defect and cystic changes in the skull corresponding to a subcutaneous mass. Bone scintigraphy revealed partial accumulation. The patient underwent total removal of the skull mass, and the diagnosis from the pathological findings of the cyst wall was fibrous dysplasia (FD). The radiographic findings for cystic cranial FD can be various. Progressive skull disease has been reported to be associated with head trauma, but the relationship between cranial FD and head trauma has not been previously reported. Previous studies have suggested that c-fos gene expression is a key mechanism in injury-induced FD.
Archive | 1988
Hirotsugu Samejima; Satoshi Iwabuchi; Nobuo Yoshii
It took 10 years to recognize the laser for its neurosurgical application since Rosomoff1 tried to use a ruby laser for surgery on a brain tumor. Today three lasers, CO2, argon and Nd:YAG, are widely used for neurosurgery. Among these lasers, the Nd:YAG has been evaluated to be inappropriate for neurosurgery, in spite of its excellent hemostatic capability, because of an unsatisfactory cutting-off effect. At the same time, this ability to achieve hemostasis has been highly successful in endoscopic procedures.
Surgery Research and Practice | 2014
Arata Tomiyama; Junichi Harashina; Hitoshi Kimura; Keisuke Ito; Yoshihiko Honda; Hiroyuki Yanai; Satoshi Iwabuchi
In 1999, a 50-year-old woman underwent ventriculoperitoneal (VP) shunt surgery for hydrocephalus after subarachnoid hemorrhage. She was hospitalized for fever and recurrent systemic seizures in November 2006. Head computed tomography (CT) showed only old changes. The seizures and fever were controlled by medicinal therapy. However, in December, her consciousness level suddenly decreased, and she showed progressive lower abdominal distension. Head CT showed marked ventriculomegaly, and abdominal CT showed a giant cystic mass at the shunt-tube tip in the lower abdominal cavity. Because thick pus was aspirated from the intra-abdominal mass, we diagnosed the patient with acute obstructive hydrocephalus due to an infected abdominal pseudocyst. Laparotomy and direct cyst drainage were performed, and antibiotic therapy against Streptococcus, the causative pathogen, was administered. The VP shunt tube was replaced. The postoperative course was uneventful, and postoperative CT showed hydrocephalus improvement and no pseudocyst recurrence. Abdominal pseudocysts, which are rare after VP shunt surgeries, usually occur after the subacute postoperative course in younger cerebral hemorrhagic cases. Our case was quite rare because the cyst developed in the chronic phase in an older patient and was caused by streptococcal infection. The cyst components should be examined before cyst drainage when choosing surgical strategies.