Minoru Oishi

Corpus callosum atrophy and cerebral blood flow in chronic alcoholics

The corpus callosum atrophy and cerebral blood flows were investigated in chronic alcoholics without Marchiafava-Bignami disease. Fifteen cases of chronic alcoholics and 15 age-matched healthy controls were studied. The sagittal plane of magnetic resonance imaging of the head was scanned into a computer and the corpus callosum was measured and the callosal index was calculated. Cerebral blood flows were measured using stable xenon computed tomography (CT) method. Regional cerebral blood flows in the frontal, temporal, parietal and occipital cortex, frontal, temporal and occipital white matter, caudate nucleus, putamen and thalamus were measured. The corpus callosum area, the thickness of the genu, the thickness of the trunk, the thickness of the splenium, and the callosal index were significantly smaller in the chronic alcoholic group than in the healthy control group. Blood flows in the cerebral cortex, thalamus and putamen were significantly lower in the chronic alcoholic group than in the healthy control group. Significant positive correlations were present between the corpus callosum atrophy and the cerebral cortex blood flows. Corpus callosum atrophy and decreased cerebral blood flows may be seen in chronic alcoholics without Marchiafava-Bignami disease.

Effects of Intravenous L-Dopa on P300 and Regional Cerebral Blood Flow in Parkinsonism

The P300 and regional cerebral blood flow were measured before and after intravenous injection of L-dopa in 10 patients with idiopathic Parkinsons disease and 10 patients with vascular parkinsonism. The P300 was measured with an evoked potential recorder using an oddball paradigm and the regional cerebral blood flow was measured using the stable xenon computed tomography method. The P300 latency was significantly longer and the regional cerebral blood flow in the cerebral cortex and basal ganglia was significantly lower in the Parkinsons disease group and the vascular parkinsonism group than in the age-matched healthy control group. The intravenous injection of L-dopa improved these abnormalities significantly in the Parkinsons disease group but did not improve these abnormalities in the vascular parkinsonism group. Cognitive function is considered to be impaired in Parkinsons disease and vascular parkinsonism and L-dopa is considered to improve it in Parkinsons disease.

Cerebral Blood Flow in Single and Multiple Lacunar Infarctions

BACKGROUND AND PURPOSE Single and multiple lacunar infarctions may have some difference in underlying diseases and cerebral blood flows. To determine the difference, we investigated underlying diseases and cerebral blood flows in single and multiple lacunar infarctions. METHODS Fifteen cases of lacunar infarction, 10 cases of multiple lacunar infarctions, and 16 control subjects were studied. Regional cerebral blood flow was measured within 14 days after stroke onset with the stable xenon CT method. RESULTS The rate of association of diabetes mellitus was higher in the multiple lacunar infarctions group than in the single lacunar infarction group. The blood flow in the cerebral cortex was significantly lower in the multiple lacunar infarctions group than in the single lacunar infarction group. The blood flow change by acetazolamide in the cerebral cortex was significantly lower in the multiple lacunar infarctions group than in the single lacunar infarction group. CONCLUSIONS There is some difference in underlying diseases and cerebral blood flows between single and multiple lacunar infarctions.

Central motor conduction time and regional cerebral blood flow in patients with leuko-araiosis

Central motor conduction time (CMCT) and regional cerebral blood flow were investigated in 21 patients with leuko-araiosis. The severity of dementia was examined using mini-mental state examination. The head magnetic stimulation was performed using an SMN-1100 magnetic stimulator and a round coil with a diameter of 17 cm. The regional cerebral blood flow was measured using the stable xenon computed tomography method. The CMCT was significantly longer in the patients with dementia than in the patients without dementia. The blood flows in the parietal cortex, frontal white matter and thalamus were significantly lower in the patients with dementia than in the patients without dementia. There were significant negative correlations between the CMCT and the blood flows in the frontal cortex, temporal cortex, frontal white matter and thalamus. The significant negative correlations suggest that the prolongation of CMCT in patients with leuko-araiosis is related to the decrease in regional cerebral blood flows.

Correlations between P300 components and regional cerebral blood flows.

To evaluate the diagnostic importance of event-related potential P300, the correlation between P300 and regional cerebral blood flow (rCBF) was investigated in various brain regions in patients with multiple cerebral infarction (16 cases), chronic alcoholism (11 cases) and Alzheimers disease (5 cases) and in seven healthy people. Cognitive function was also evaluated by mini-mental state examination. P300 latency and rCBF was measured by recording of evoked potentials using an oddball paradigm and stable xenon computed tomographic scanning, respectively. A significant (P<0.05) negative correlation between P300 and rCBF was observed in the thalamus in patients with multiple cerebral infarction and chronic alcoholism. In addition, a significant (P<0.01) negative correlation between P300 latency and the mini-mental state examination score and positive correlation between rCBF in the thalamus and the mini-mental state examination score were observed. These findings suggest that P300 latency is associated with rCBF in the thalamus and cognitive function.

Atrophy of the parahippocampal gyrus and regional cerebral blood flow in the limbic system in chronic alcoholic patients.

This study investigated regional cerebral flood flow (CBF) in chronic alcoholic patients, focusing primarily on the limbic system, including the hippocampus and the callosomarginal region, because of their susceptibility to damage in such patients. The degree of hippocampal atrophy in such patients was also examined. Regional CBF and the degree of parahippocampal gyrus atrophy were studied in 22 chronic alcoholic male patients with no neurological or psychological symptom (mean age, 59.3+/-4.1 years). Their findings were compared with those of 22 age-matched, male, normal controls (mean age, 59.7+/-3.9 years). Single-photon emission computed tomography was performed using the (99m)Tc-ethylcysteinate dimer ( (99m)Tc-ECD) Patlak Plot method, and the three-dimensional stereotaxic region of interest (ROI) template (3DSRT) and the fine stereotaxic ROI template (fine SRT) developed by Takeuchi et al were used to evaluate regional CBF, focusing primarily on the limbic system. These methods make it possible to precisely and objectively measure the details of regional CBF. The voxel-based specific regional analysis system for Alzheimers disease (VSRAD) was used to determine the degree of parahippocampal gyrus atrophy in chronic alcoholic patients. VSRAD is a method developed by Hirata et al for evaluating the degree of atrophy of the parahippocampal gyrus. The results were analyzed using Z scores (>2 indicating significant atrophy). Blood flows in the callosomarginal region, pericallosal region, thalamus, hippocampus, parahippocampal gyrus, amygdaloid body, anterior cingulate gyrus, and middle cingulate gyrus were lower in the chronic alcoholic group than in the control group. Parahippocampal gyrus atrophy was not observed in the control group (average Z score, 0.62+/-0.29). In contrast, an atrophic tendency was observed in the chronic alcoholic group (average Z score, 1.88+/-0.44). Clinically intact, chronic alcoholic patients with no neurological or psychological symptom had decreased CBF in the limbic system and a tendency to parahippocampal gyrus atrophy.

Clinical study of twenty-one patients with pure midbrain infarction.

We investigated the neurological and MRI findings of 21 patients with pure midbrain infarction. The locations of the infarcts were classified into paramedian (PM) area (13 patients), lateral area (6 patients), and PM and lateral areas (1 patient), based on the distribution of each penetrating artery of the midbrain. The infarction of 1 patient showed bilateral multiple lesions. In the PM area group, 12 patients showed eye movement disorders and truncal and gait ataxia. Eye movement disorders consisted of medial longitudinal fasciculus syndrome, oculomotor nerve palsy, and bilateral vertical gaze palsy. The infarcts of the 2 patients with bilateral vertical gaze palsy were located in the PM area on both sides. Eye movement disorders and truncal and gait ataxia were prominent in the PM area group. Ataxic hemiparesis was shown in 2 patients of the PM area group and 4 patients of the lateral area group. We showed that ataxic hemiparesis also occurred in PM area infarction, although ataxic hemiparesis was a prominent feature of lateral area infarction.

A patient with Marchiafava–Bignami disease as a complication of diabetes mellitus treated effectively with cortico steroid

We report a 37-year-old woman with no history of alcohol consumption or malnutrition who had Marchiafava-Bignami disease (MBD) as a complication of diabetes mellitus. The patient suddenly developed dizziness and could not speak words fluently. Neurological examination revealed acalculia, agraphia, left blepharoptosis, and mild left facial palsy. Her blood glucose was 391 mg/dL, and her glycated hemoglobin (HbA1c) was 16.0%. Her brain MRI revealed hyperintense changes in the corpus callosum on T2-weighted, fluid-attenuated inversion recovery and diffusion-weighted images. In addition to therapy for diabetes mellitus, prednisolone was commenced. All of the symptoms gradually improved, and after three months, only slight dysarthria, acalculia, and agraphia were observed. Brain MRI also revealed a reduction in lesion size. In conclusion, MBD may occur even with metabolic disorders. It is important to diagnose MBD in the early stages with MRI and to treat the symptoms with cortico steroids.

Regional cerebral blood flow and cerebrospinal fluid glutamate in leukoaraiosis.

Abstract. Cerebral blood flow and cerebrospinal fluid amino acids were investigated in patients with leukoaraiosis on magnetic resonance imaging. Ten patients with leukoaraiosis and without significant cerebral infarction and ten age-matched controls without abnormality on magnetic resonance imaging were studied. The regional cerebral blood flow was measured using the stable xenon computed tomography method. The blood flow was significantly lower in the leukoaraiosis area in the leukoaraiosis group than in the same area in the control group. The cerebrospinal fluid glutamate concentration was significantly higher in the leukoaraiosis group than in the control group. There was a significant negative correlation between the blood flow in the leukoaraiosis area and the cerebrospinal fluid glutamate concentration. The high concentration of cerebrospinal fluid glutamate in patients with leukoaraiosis is considered to be related to ischaemia.

Central motor conduction time in patients with periventricular lucencies

Central motor conduction time and regional cerebral blood flow were measured before and 20 min after intravenous injection of 17 mg/kg acetazolamide in 10 patients with periventricular lucencies (PVL) and 10 age-matched healthy controls. Central motor conduction time was measured using a magnetic stimulator and regional cerebral blood flow was measured by stable xenon computed tomography method. The central motor conduction time was significantly longer in the patients with PVL than in the healthy controls and was shortened significantly by the intravenous injection of acetazolamide in the patients with PVL. The blood flow not only in the periventricular white matter but also in the cerebral cortex and the cerebral white matter was significantly lower in the patients with PVL than in the healthy controls. The intravenous injection of acetazolamide increased significantly the regional cerebral blood flow except in the PVL areas. The prolongation of the central motor conduction time may be at least partly related with decreased blood flow in the cerebral cortex and cerebral white matter.