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T Kawase

Publications and source records attributed to T Kawase.

At least 289 records · Page 16Linked to original sources

Topographic electroencephalographic study of cerebral infarction using computed mapping of the EEG.

Computed mapping of the electroencephalogram (CME) is a newly developed method using a microcomputer system that displays the scalp topograph as the square roots of the average power spectra over each EEG frequency band on a color television screen. This new device has been employed in an examination of functional lesions in 20 patients with aphasia due to cerebral infarction. The results were compared with those of computer tomography (CT) and regional cerebral blood flow (rCBF) studies using intracarotid 133Xe. A high-voltage focus of slow components and an asymmetrical distribution of alpha activity were regarded as signs of functional lesions on CME. Twelve patients showed high-voltage foci and six showed asymmetrical alpha activity on CME, which correlated well with the lesions on CT and/or rCBF studies. Especially in patients with motor aphasia, CME demonstrated the abnormality in advance of the appearance of a low-density area on CT. Compared with conventional EEG interpretation, CME is very useful in topographic and objective diagnosis of functional lesions, although the source of the data is the same as for the conventional EEG.

Alpha Rhythm↗

Prevention of vasospasm by early operation with removal of subarachnoid blood.

Sixty-four patients who were operated on within 4 days after acute subarachnoid hemorrhage are included in this study. All patients underwent preoperative computed tomographic (CT) scanning, and the amount and distribution of subarachnoid blood clot were noted. Operation was carried out by the frontobasal lateral approach, and the subarachnoid clot was removed by microsurgical suction-irrigation after clipping of the aneurysm. Immediate postoperative CT scanning was performed to evaluate the completeness of the subarachnoid blood clot removal. The presence or absence of postoperative vasospasm was determined with angiography performed between the 7th and 10th postoperative days. All patients were, of course, also evaluated for evidence of neurological deterioration. Approximately two-thirds of the patients in this series showed high density subarachnoid blood clot on the preoperative CT scan. The postoperative CT scans showed that it was possible to remove the majority of the blood clot except that located in the frontal interhemispheric fissure, the posterior part of the insular cistern on the approached side, and all of the insular cistern on the contralateral side. There was no spasm or only mild spasm in any site where the blood clot had been successfully removed. Delayed neurological deficits occurred only in those cases in which subarachnoid blood clot remained in the cisterns. These results suggest that it is possible to prevent intracranial arterial spasm and associated neurological deterioration by early operation and removal of clotted blood from the subarachnoid space.

Adult↗

[Dynamic pathophysiology of cerebral infarction and revascularization. I. Ischemic cerebral edema].

A natural history of ischemic cerebral edema was analyzed in 100 patients with occlusive cerebrovascular diseases admitted within one week of onset, with serial computed tomography (CT) and angiograms. Cerebral edema was defined as a low-density area with mass sign on CT. A total of 446 studies of CT were performed. In 40 patients with major completed stroke admitted 24 hours of onset, a total of 73 studies of CT were taken within 48 hours of onset, and a timing of appearance of cerebral edema was analyzed. Patients were allocated to two groups according to the findings on angiograms; 68 patients who showed occlusive lesions on sequential angiograms (the group of no-recanalization), and 32 patients who showed reopening of occluded vessels on the first or sequential angiograms (the group of no-recanalization). In the group of no-recanalization a low-density area gradually appeared between 6 and 24 hours of onset A. mass sign reached its peak on the 3rd day with a peak incidence of 56%, and midline shift was present in 30% of the cases. It was resolved within 2 weeks in most cases. In the group of recanalization, a low density area appeared after 4 hours and rapidly increase after 6 hours. All patients had a low-density area at 12 hours of onset. A mass sign progressed until the 6th day with a peak incidence of 82%, and midline shift was present in 50% of the cases. The duration of mass sign was longer than that in the group of no-recanalization. These results suggest that the permissible duration of ischemia is considered to be within 6 hours of onset in profound ischemia. After 6 hours, ischemic tissue damage may not be reversible by the revascularization, even if CT shows no change during ischemia. An abrupt revascularization may not contribute to the recovery of brain damage, but accelerate the ischemic cerebral edema.

Aged↗

Galactosyltransferase activities in human sera of various diseases.

Recently galactosyltransferase has been noted as a new tumor marker. In this report galactosyltransferase activity was measured in sera of various diseases including malignant tumors and the levels of the enzyme activities were compared. The levels of the enzyme were higher in sera of malignant tumors and liver diseases than those in sera of other diseases. In malignant tumors little organ specificity was found with respect to the levels of galactosyltransferase activities. The levels of the enzyme were considered to have no relation to carcinoembryonic antigen or alpha-feto protein. On the other hand, in liver diseases the levels of the enzyme were correlated to the severity of liver damage. Therefore, it is reasonable to presume that the elevation of serum galactosyltransferase activity is caused chiefly by malignant tumors and liver damage.

Galactosyltransferases↗

[Angiographic vasospasm and regional cerebral blood flow in the cases of ruptured aneurysm --Correlation between vasospasm in the middle cerebral artery and delayed ischemic hemiparesis (author's transl)].

It is well known that the vasospasm following rupture of aneurysm causes ischemic neurological symptoms. However, there are a few literatures which refer to the relationship between the severity of angiographic vasospasm and regional cerebral blood flow (rCBF) and ischemic neurological symptoms. To elucidate this problem, 41 patients with ruptured aneurysm were analysed by means of repeated cerebral angiography and rCBF study, and the following results were obtained. 1. Mean rCBF was reduced to its lowest level in the second week of hemorrhage and at this stage, the values of mean rCBF were well correlated with the severity of the angiographic vasospasm and with the development of delayed ischemic neurological symptoms. 2. The morphological feature of the angiographic vasospasm was a smooth narrowing of the vessels, and the delayed ischemic hemiparesis occurred when both M-1 and M-2 portions of the middle cerebral artery are narrowed more than half comparing the calibers as seen within 3 days of hemorrhage. 3. The average of mean rCBF in 15 patients with symptomatic spasm was 27.0 +/- 5.5 ml/100 g/min. and that in 11 patients with asymptomatic spasm was 40.8 +/- 8.8 ml/100 g/min. As a conclusion, the prognosis of the patients with angiographic vasospasm may be predicted through the value of rCBF and the severity of angiographic vasospasm in the second week of hemorrhage.

Adult↗

Value of computed tomography in the prediction of cerebral vasospasm after aneurysm rupture.

The relationship between high density (HD) on computed tomographic (CT) scans (which indicates a collection of blood in the subarachnoid space) and cerebral vasospasm was studied in 177 patients with ruptured aneurysm. The development of cerebral vasospasm was confirmed at the high rate of 84.6% in 26 cases where HD was demonstrated on the CT scan within 4 days after subarachnoid hemorrhage (SAH). In 8 cases where HD was not found on the CT scan obtained within 4 days after SAH, no cerebral vasospasm was seen. However, no relationship was found between HD and the occurrence of cerebral vasospasm in cases in which CT was performed after the 5th day of disease. It is suggested that CT performed within 4 days after SAH may give important information for predicting cerebral vasospasm.

Adult↗

Acute effect of the carbon dioxide laser on the epicerebral microcirculation. Experimental study by fluorescein angiography.

The effect of laser radiation on the central nervous system has been studied in cases of clinical and experimental tumors. However, no report yet exists on the effects of laser radiation on the cerebral microcirculation in vivo. Cerebral fluorescein angiography permits observations of small vessels that are not possible by conventional angiography. In this study, disturbance in the epicerebral microcirculation after carbon dioxide laser radiation was localized. On fluorescein angiograms, a circular zone of nonfilling of fluorescein dye around the site of impact, 1 to 1.5 mm in diameter, was seen throughout from the arterial to later venous phase. Around the nonfilling area, thrombus formation in small vessles and extravasation of the dye were demonstrated. Such extravasation of the fluorescein remained after the dye had faded from the venules and veins. Microscopically, coagulation necrosis was observed to coincide with the area of nonfillin of fluorescein dye in the fluorescein angiograms. In areas surrounding this, edema, dilatation or rupture of the capillaries, and thrombus formation in the arterioles were observed. Such areas coincided with those of extravasation of the fluorescein dye.

Animals↗