Yasunori Mito
Hokkaido University
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Featured researches published by Yasunori Mito.
Clinical Neurology and Neurosurgery | 2005
Yasunori Mito; Kazuto Yoshida; Ichiro Yabe; Kenichi Makino; Makoto Hirotani; Kunio Tashiro; Seiji Kikuchi; Hidenao Sasaki
OBJECTIVES Cerebral blood flow was compared among patients with dementia with Lewy bodies (DLB), Parkinsons disease with dementia (PDD), Parkinsons disease without dementia (PD), and Alzheimers disease (AD) using three-dimensional stereotactic surface projection (3D-SSP) analysis. PURPOSE We attempt to clarify the difference of reduction pattern on SPECT among patients having DLB, PDD, PD, AD. PATIENTS AND METHODS Six patients with DLB, 7 patients with PDD who were matched with the DLB patients for age, unified Parkinsons disease rating scale-III (UPDRS-III) score, and degree of cognitive function disorders, 21 patients with PD who were matched with the DLB patients for age, UPDRS-III score, 12 patients with AD who were matched with the DLB patients for age and degree of cognitive function disorders, and 12 control subjects. All patients were examined by N-isopropyl-p[123I] iodoamphetamine single photon emission computed tomography (123I-IMP SPECT), and obtained images were analyzed with 3D-SSP using an image-analysis software, iSSP ver. 3.5. RESULTS Although DLB and PDD showed similar cerebral perfusion reduction pattern at the lateral parietal association and lateral temporal association and precuneus on SPECT by the pixel-by-pixel comparison, greater perfusion reduction was observed in DLB than in PDD. Cerebral perfusion was decreased at the occipital lobe of the DLB patients compared with the AD patients. CONCLUSIONS The regional pattern of blood flow reduction in the brain was found to be different among DLB, PD, and AD. Greater blood flow reduction was observed in DLB, although DLB and PDD showed similar reduction pattern. These regional differences were considered to suggest different and disease-specific combinations of underlying pathological and neurochemical processes.
Journal of the Neurological Sciences | 2006
Yasunori Mito; Kazuto Yoshida; Ichiro Yabe; Kenichi Makino; Kunio Tashiro; Seiji Kikuchi; Hidenao Sasaki
OBJECTIVES We hypothesize that the regional pattern of blood flow reduction in the brain is different between tremor-dominant Parkinsons disease (PD) and postural instability gait difficulty (PIGD)-dominant PD. We therefore investigated the association of phenotypes in untreated PD with brain perfusion on SPECT using three-dimensional stereotactic surface projection (3D-SSP) technique. PATIENTS AND METHODS Thirty-three patients who had PD without dementia (12 men and 21 women with a mean age of 67.1+/-6.4 years) were included in this study. Their symptoms were rated using the Unified Parkinsons Disease Rating Scale (UPDRS). Patients were grouped in two phenotypes: tremor and PIGD-dominant groups based on UPDRS components. Around the same time, all patients were examined by N-isopropyl-p[123I] iodoamphetamine single photon emission computed tomography (123I-IMP SPECT), and obtained images were analyzed with 3D-SSP using an image-analysis software, NEUROSTAT. Data on brain surface perfusion extracted by 3D-SSP analysis were compared between the PD patients and the normal control group. The same comparisons were made for subgroups of PD patients. RESULTS Cerebral perfusion was decreased at the anterior cingulate cortex and primary visual cortex of the PD patients, and especially by the pixel-by-pixel comparison, perfusion was significantly decreased at the right anterior cingulate cortex compared with the normal controls. In the PIGD-dominant group, more severe hypoperfusion was seen at the same regions. In the tremor-dominant group, significant hypoperfusion was not seen compared with the normal controls. CONCLUSIONS The regional pattern of blood flow reduction in the brain was found to be different between tremor-dominant PD and PIGD-dominant PD. These regional differences were considered to suggest different and disease-specific combinations of underlying pathophysiological and neurochemical processes.
Clinical Neurology and Neurosurgery | 2009
Masakazu Nakamura; Ichiro Yabe; Hiroaki Yaguchi; Riichiro Kishimoto; Yasunori Mito; Naoto Fujiki; Hideki Houzen; Sachiko Tsuji-Akimoto; Masaaki Niino; Hidenao Sasaki
OBJECTIVE To confirm the reported findings and clarify unknown clinical features of Churg-Strauss syndrome (CSS)-associated neuropathy and design appropriate treatment. PATIENTS AND METHODS We assessed the clinical features of 6 patients with CSS-associated neuropathy. RESULTS Mononeuritis multiplex was present in 4 cases and polyneuropathy in the remaining cases. Both groups progressed to sensori-motor polyneuropathy in an acute or subacute course. All cases showed bronchial asthma and eosinophilia. Two cases with serum antineutrophil cytoplasmic antibodies to myeloperoxidase (MPO-ANCA) had an acute clinical course and severe symptoms. Nerve conduction studies (NCS) of these 2 cases revealed conduction blocks at the initial stage, although NCS finally indicated sensori-motor axonopathy at the involved extremities. For treatment, high-dose corticosteroid therapy for 4 cases, and cyclophosphamide combined with corticosteroids for 1 case, were effective. For the remaining case, intravenous immunoglobulin (IVIg) at the chronic phase resulted in a slow improvement of neuropathy in the symptomatic aspect. There was no relapse of neuropathy with low-dose corticosteroid treatment for 14-24 months after the initial treatment, except 1 case. There was also no relapse in the other case that was treated with moderate-dose steroids. CONCLUSION Our study showed that CSS-associated neuropathy is a treatable disorder and that the first choice therapy is high-dose corticosteroid. In cases where corticosteroids are ineffective or for severe cases, immunosuppressive therapy (cyclophosphamide) with steroids should be considered, and IVIg might be a treatment option.
Psychiatry and Clinical Neurosciences | 1994
Yasutaka Tajima; Yasunori Mito; Yoshiko Owada; Fumio Moriwaka; Kunio Tashiro
Abstract: Subacute combined degeneration (SCD) of the spinal cord is well known to produce degenerative lesions in the spinal cord histopathologically, but a few reports on the neuroradiological findings have so far been reported. We presented the MRI findings of the spinal cord in a case of SCD. The localization of the radiologically proven lesions was similar to that of the previous pathological reports.
Case Reports | 2012
Yasutaka Tajima; Yasunori Mito
A 64-year-old man suffering from chronic heart failure developed gradually worsening dysphagia 1 month before. Physical examinations revealed no abnormalities, such as proptosis and parotid swelling. Neurological examinations revealed hoarseness, poor soft palate elevation and right-sided atrophy of the tongue and sternocleidomastoid muscle. The patients DTRs were slightly hypoactive, but no pathological reflexes were elicited. Cerebellar systems were intact, …
Case Reports | 2012
Yasutaka Tajima; Yasunori Mito; Mituru Yanai; Yu-ichiro Fukazawa
A 64-year-old man suffering from diabetes mellitus and chronic renal failure was admitted to our hospital because of consciousness disturbance and parkinsonism. Cranial MRI showed very characteristic features involving the bilateral basal ganglia. Subsequent postmortem examinations demonstrated demyelination in the affected areas. These myelin destruction patterns were quite similar to those of central pontine myelinolysis. However, rapid correction of hyponatraemia was ruled out in this patient. Therefore, a new demyelinating brain disease associated with diabetes mellitus and chronic renal failure was suggested.
Journal of the Neurological Sciences | 2016
Yasunori Mito; Ichiro Yabe; Hiroaki Yaguchi; Yasutaka Tajima
OBJECTIVES The aim of the present study was to determine the associations of motor symptoms in untreated Parkinsons disease (PD) with urinary dysfunction. We therefore examined the association between the overactive bladder symptom score (OABSS) and Unified Parkinsons Disease Rating Scale (UPDRS). PATIENTS AND METHODS Thirty-one untreated PD patients without dementia (12 men and 19 women with a mean age of 72.0±6.7years) were included in this study. Their urinary tract dysfunctions were rated using the OABSS. The motor symptoms of all patients were also assessed using UPDRS. RESULTS OABSS had significant correlations with UPDRS motor score (Spearmans rho=0.39, p=0.03) and akinetic-rigid score (Spearmans rho=0.47, p=0.01). However, OABSS showed no significant correlation with tremor score, age, or duration of PD. CONCLUSIONS Higher OABSS was consistently associated with increase in severity of motor disorders, especially akinetic-rigid score, in the study participants.
Case reports in neurological medicine | 2016
Yasutaka Tajima; Mariko Matsumura; Hiroaki Yaguchi; Yasunori Mito
In rare instances, recipients of organ transplants from human T-lymphotropic virus type I- (HTLV-I-) positive donors reportedly developed neurologic symptoms due to HTLV-I-associated myelopathy (HAM). We present herein two cases of HAM associated with renal transplantation from HTLV-I seropositive living-donors. The first patient was a 42-year-old woman with chronic renal failure for twelve years and seronegative for HTLV-I. She underwent renal transplantation with her HTLV-I seropositive mother as the donor, and she developed HAM three years after the transplantation. The second patient was a 65-year-old man who had been suffering from diabetic nephropathy. He was seronegative for HTLV-I and underwent renal transplantation one year previously, with his HTLV-I seropositive wife as the donor. He developed HAM eight months after renal transplantation. Both cases showed neurological improvements after the immunomodulating therapies. We tried to shed some light on the understanding of immunological mechanisms of transplantation-associated HAM, focusing on therapeutic strategies based on the immunopathogenesis of the condition.
Internal Medicine | 2018
Yasutaka Tajima; Mariko Matsumura; Hiroaki Yaguchi; Yasunori Mito
A 27-year-old woman with optic neuritis and cervical myelitis developed hypertrophic demyelinating polyneuropathy. It was hypothesized that the diagnosis was combined central and peripheral demyelination. A hypertrophic nerve was observed subcutaneously, and magnetic resonance imaging demonstrated marked hypertrophy of the nerve roots. The patient was negative for anti-aquaporin 4 antibodies. Her anti-neurofascin 155 antibody levels was slightly elevated, but it was not definitely positive. Pulsed steroid therapy and the administration of immunoglobulin ameliorated her symptoms. Molecules in both the peripheral and central nervous systems might be target antigens, but further investigations will be needed to clarify the precise pathogenic mechanisms.
Neurology and Clinical Neuroscience | 2014
Shinichi Shirai; Yasunori Mito; Tatsuru Nojo; Hiroaki Yaguchi; Toshiyuki Takahashi; Kazunori Sato; Makoto Hirotani; Takahiro Kano; Ichiro Yabe; Hidenao Sasaki
A 48‐year‐old man was admitted to Tomakomai City Hospital, Tomakomai, Japan, because of intractable hiccups and nausea, and orthostatic hypotension. Brain magnetic resonance imaging findings showed a dorsal medullary lesion. Respiratory failure occurred, and he underwent tracheotomy and mechanical ventilation when magnetic resonance imaging showed subarachnoid hemorrhage in addition to enlarged medullary lesions. Serum anti‐aquaporin‐4 antibody was positive and the cerebrospinal fluid was bloody. We diagnosed meuromyelitis optica spectrum disorders complicating subarachnoid hemorrhage. He was treated with a steroid. Although extensive white matter lesions occurred transiently, the patient was discharged from the hospital when he became able to walk with the use of the walker on the 52nd day. We suggest that the subarachnoid hemorrhage and transient white matter lesions were associated with vascular damage associated with the meuromyelitis optica spectrum disorders.