Postoperative evaluation of extracranial-intracranial arterial bypass by means of ultrasonic quantitative flow measurement and computed mapping of the electroencephalogram

As an objective evaluation of extracranial-intracranial (EC/IC) bypass operation, we studied 10 patients with occlusive cerebrovascular disease after EC/IC bypass operation using ultrasonic quantitative flow measurement (UQFM) and the computed mapping of the electroencephalogram (CME). After the operation, to evaluate the efficacy of the bypass operation, we studied all patients by UQFM and CME before and during compression of the superficial temporal artery (STA). In a control series of cases, the change in common carotid blood flow during STA compression was not statistically significant, and the findings of CME were unchanged during STA compression. In the cases with bypass surgery, reduction of the common carotid blood flow during STA compression was obvious and statistically significant (P less than 0.001). Additionally, in 5 of the 10 cases, the CME findings were aggravated during STA compression. Therefore, in these 5 cases the brain with bypass seems functionally dependent upon the bypass flow. It is suggested that the EC/IC bypass is effective at least in these 5 cases. The UQFM and the CME, which are noninvasive and simple, are very useful for postoperative evaluation of EC/IC bypass grafts from a hemodynamic and functional point of view.

Characteristic findings of metrizamide CT cisternography in epidermoids

The characteristic findings of metrizamide CT cisternography in two cases of epidermoid are reported. The main finding was a "cauliflower-like" appearance and was thought to be caused by the irregular interstices of epidermoids. Metrizamide CT cisternography may be helpful in making a diagnosis of an epidermoid.

Cell-cycle dependency of radiosensitivity and mutagenesis in fertilized egg cells of rice, Oryza sativa L. : 2. X-ray sensitivity and mutation rate during a cell cycle

In order to examine changes in survival and mutation rates during a cell cycle in higher plant, fertilized egg cells of rice were irradiated with X-rays at 2 h intervals for the first 36 h after pollination, i.e., at different phases of the first and second cell cycles. The most sensitive phase in lethality was late G1 to early S, followed by late G2 to M, which were more sensitive than the other phases. In both M1 and M2 generations, sterile plants appeared most frequently when fertilized egg cells were irradiated at G2 and M phases. Different kinds of mutated characters gave rise to the respective maximum mutation rates at different phases of a cell cycle: namely, albino and viridis were efficiently induced at early G1, xantha at early S, short-culm mutant at mid G2, heading-date mutant at M to early G1. The present study suggests the possibility that the differential mutation spectrums concerning agronomic traits are obtained by selecting the time of irradiation after pollination.

Relationship between contrast enhancement on computed tomography and cerebral vasospasm in patients with subarachnoid hemorrhage

To elucidate the relationship between abnormal enhancement of the cisterns on computed tomography and cerebral vasospasm, we performed a systematic and prospective study in 60 patients with ruptured cerebral aneurysms. There is a significant relationship between the findings of contrast-enhanced computed tomography (CECT) within Day 3 of rupture and cerebral vasospasm. Among 37 patients undergoing CECT between Day 0 and Day 3, 17 (46%) showed prominent increases in density in the region around the circle of Willis and its branches. In 13 of 17 cases (76%), severe vasospasm with motor paralysis occurred. In the remaining 4 cases (24%) with only slight or no cerebral vasospasm, the hematoma in the subarachnoid space was removed surgically by Day 3. In 19 of 20 cases without remarkable CECT, no severe cerebral vasospasm with motor paralysis occurred. There is no significant relationship between the CECT findings after Day 3 and cerebral vasospasm. The results indicate that the prominent increase in density in the region of the circle of Willis and its branches often observed on CECT within Day 3 of subarachnoid hemorrhage is useful for prediction of the occurrence of cerebral vasospasm and also provide information on the pathogenesis of cerebral vasospasm.

CT and arteriographic comparison of patients with transient ischemic attacks--correlation with small infarction of basal ganglia

Fifty patients presenting clinically with TIAs were examined angiographically. Twenty one patients (42%) had no abnormality. Twenty patients (40%) had stenosis or occlusion in the MCA, ACA or intracranial carotid, whereas 11 (22%) had involvement of their extracranial internal carotid artery. Seven of the 28 CTs performed showed basal ganglia infarcts. This suggests that the cause for the TIA was an infarct in the vascular territory of a lenticulostriate artery.

[Dynamic pathophysiology of cerebral infarction and revascularization. III. Changes of regional cerebral blood flow]

Thirty-eight patients with occlusive cerebrovascular disease were followed with regional cerebral blood flow (rCBF) measurement, angiography and computerized tomography (CT) to know the time course of rCBF in cerebral infarction. The rCBF study was carried out by the 133Xe intracarotid injection method with 16 scintillation detectors. They were allocated to two groups according to the findings on angiograms; 15 patients having any change of occlusive lesion (the group of no-recanalization ) and 23 patients showing reopening of occluded vessels (the group of recanalization). A mass sign and an extent of cerebral infarction were observed on CT. In the group of no-recanalization, a mean value of rCBF (mean rCBF) in acute stage was well correlated to the severity of ischemic stroke. In minor completed strokes the average mean rCBF was 35.8 +/- 3.7 ml/100g/min, which is significantly higher than that in major strokes and progressing strokes of 24.8 +/- 3.9 ml/100 g/min (p less than 0.001). Sequential change of mean rCBF was not prominent in the group of no-recanalization. However, rCBF change was conspicuous in the group of recanalization. In acute stage of recanalization, rCBF were markedly affected by the presence of mass sign (cerebral edema) on CT. When CT showed midline shift of structure, mean rCBF was markedly reduced, and when without midline shift, focal hyperemic areas were sometimes observed in the revascularized area. Thus, the inhomogeneity of rCBF was characteristic in cases with recanalization. The focal hyperemia usually disappeared within one week in cases of minor stroke and lasted until 2 or 3 weeks in cases of major stroke. In chronic stage, mean rCBF decreased, and there was no significant difference of averaged rCBF between two groups. Those findings suggests that the main factor influenced on the sequential change of rCBF is reopening of occluded vessels. Regional CBF may depends both on the degree of cerebral edema and the extent of vasoparesis after revascularization. In chronic stage CBF value is not always dependent to the presence of occlusive lesion but might be reflected in the total brain function.

[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.

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.

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.

[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.

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.

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.