Effect of glycerol on ischemic edema evaluated by somatosensory evoked potentials.

Glycerol is administered to reduce intracranial pressure by clinically enhancing cerebral edema. In this study, the effect of glycerol on ischemic edema was evaluated in 34 cerebral infarct patients by serial SEP. Evoked potentials were obtained by stimulating the hemiparetic median nerve 60 times with duration of 0.1 msec. N20 wave of SEP was analyzed by signal processor. SEP was monitored every 30 min for 3 hr after glycerol administration. Improvements of CCT, which means interpeak latency between N13 and N20, were observed in 14 patients. In seven patients, N20 waves were observed after IV administration of glycerol even though N20 waves were not observed before glycerol administration. The patients in acute stage or with the small infarction of basal ganglia showed these electrophysiological improvements. No CCT changes were observed in nine patients, and no N20 waves were obtained in two patients even after glycerol administration. In conclusion, electrophysiologically, glycerol effect on ischemic edema was well recognized in acute staged infarct patients and the patients with small infarction of basal ganglia.

Electropalatographic analysis of apraxia of speech in a left hander and in a right hander.

Two cases with 'pure' apraxia of speech are reported. The articulatory disturbances were quite similar. One of the two cases was a left-handed male with a subcortical haemorrhage and the other a right-handed male with a cerebral infarct. The MRI and CT scans showed that the first case had a lesion that mainly involved the right precentral gyrus and its deep white matter, and that the second had a lesion mainly affecting the lower parts of the left precentral and postcentral gyri and their deep white matter. These findings and a literature review suggest that a corticosubcortical lesion of the lower part of the left precentral gyrus in most right handers and a lesion of the symmetric region in the right hemisphere in some left handers cause apraxia of speech. The omission errors for sounds articulated by the tongue and the hard palate were analysed using electropalatography, which records visually the dynamics of the palatolingual contact. The results demonstrated that there were three kinds of omission errors: true omissions (no palatolingual contact); omissions with incorrect contact (palatolingual contact for a different sound or undifferentiated sound); and omissions with correct contact (correct palatolingual contact for a target sound). The latter two types of omission error were observed for initial consonants and they were probably caused by a delay in air flow. The patients also showed a tendency to substitute one of the two consonants/t, t/for other sounds, which suggested that they had difficulty in the inhibition of tongue activity.

Pharmacokinetic Study of Cefotaxime (CTX) in Dogs.

Cefotaxime (CTX) was injected either intravenously or intramuscularly in dogs, and its pharmacokinetics in plasma and urine were determined with the use of HPLC assay. Cephalothin (CET) was administered in a similar manner as a reference agent. While both CTX and CET rapidly disappeared from plasma after intravenous injection, the half-life of CET was approximately 2.5 times shorter than that of CTX. Both drugs were deacetylated, and desacetyl-CTX and desacetyl-CET appeared in plasma. Both drugs were rapidly excreted into urine either in unchanged or deacetylated form, the sum of which accounted for 77 % and 63 % of the CTX and CET dose, respectively. The ratio of the amount of unchanged drug over that of deacetylated drug in the urine was 1:1 for CTX and 1:2 for CET. When CTX and CET were intramuscularly injected, the plasma levels of CTX and CET reached a maximum 30 min and 15 min after injection, respectively, followed by a rapid decline. The pattern of urinary CTX excretion was similar after i.m. and i.v. injections. In contrast, the amount of desacetyl-CET in the urine was larger after i.m. than i.v. injections. CTX metabolites other than desacetyl-CTX (M2 and M3) that were also assayed by HPLC accounted for only 2-4 % of the dose of CTX in the urine, but were below detectable levels in this plasma.

[Some considerations on surgical approaches to the anterior communicating artery aneurysms--radiological study of 122 cases].

We studied the operative approaches to anterior communicating artery aneurysms by means of reviewing preoperative angiogram and operation records. During the past 5 years, 117 patients with anterior communicating artery aneurysms were operated on in our hospital. Among these, we examined 112 cases of which preoperative angiogram and operation records were satisfactory for this study. We checked the next points on the preoperative angiograms. Neck of aneurysm-planum sphenoidal distance. Direction of the anterior communicating artery. It means which A2 is anterior to the other A2 in the lateral view of angiogram. Size of aneurysm. We checked the next points on the operation records. Operative approach and the side of craniotomy. When the pterional approach was taken, the rectal gyrus was aspirated or not. This analysis derived these two conclusions as below. 1. In the literature, as the operative approach to anterior communicating artery aneurysm, the pterional approach has a lot of advantages. For example, the pterional approach was accomplished without extensive frontal lobe retraction, without mobilization of the temporal lobe, without sacrificing the olfactory tract, and so on. Moreover, in early stage after onset of SAH, it is possible to remove the subarachnoid blood extensively without obvious brain damage by the pterional approach. In this study, we paid attention to the correlation between the neck-planum sphenoidal distance and the fact of aspiration of the rectal gyrus in the pterional approach. The result is that the higher aneurysmal neck was, the more frequently the rectal gyrus was aspirated. So, if the neck-planum sphenoidal distance is under 12 mm, which includes the majority of the cases (94% of cases), we think the pterional approach is the best approach for anterior communicating artery aneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)

[Use of real-time ultrasonography in neurosurgical operations].

The authors' experience with the application of real-time ultrasonography during 29 and after 3 neurosurgical operations is reported. Intraoperative sonography was performed in 29 cases. The neurosurgical operations include aneurysm surgery in 13 cases, removal of intracerebral hematoma in 11 cases, neoplasm surgery in 2 cases, and so on. Moreover, sonographic examination through bone defect was performed in 3 cases after decompression craniectomy. The instrument used was an ATL (Advanced Technology Laboratories, Bellevue, WA, USA) mechanical sector scanner of which scanhead contained transducers of three frequencies: 3, 5 and 7.5 MHz. The scanhead was wrapped with a sterile rubber bag after acoustic coupling gel had been applied to the head's tip. Then the scanhead was placed on the dura and ultrasonic examination was performed. The result was that the lesion was clearly identified and localized in all cases except for three cases of mild subarachnoid hemorrhage. In addition, in the two cases of needle aspiration of cyst or hematoma, the needle was easily identified and needle aspiration was performed safely and accurately. Moreover, during aneurysm surgery, aneurysm itself was detected in two cases by the real-time ultrasonic imaging. Especially, in the case with large aneurysm of the left middle cerebral artery, the findings about the aneurysmal wall, that is to say, which part is thick and which part is thin, could be obtained. Prior to the operation of aneurysm, cerebral angiogram and computerized tomographic scan are always examined thoroughly, but information about aneurysmal wall can be rarely obtained by them.(ABSTRACT TRUNCATED AT 250 WORDS)

Intraoperative use of real time ultrasonography applied to aneurysm surgery.

The intraoperative application of real time ultrasonography during 13 neurosurgical operations for intracranial aneurysms is reported. In 2 cases, the aneurysms themselves could be detected clearly by real time ultrasonic imaging. In the case of a large aneurysm, information about the nature of the aneurysmal wall was obtained. Other lesions coexisting with the aneurysm (namely, intracerebral hematoma, massive subarachnoid hemorrhage, and hydrocephalus) could be recognized clearly. Real time intraoperative ultrasonography is considered to be useful in aneurysm surgery.

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.

Effects of imipramine, nomifensine and d-amphetamine on type B monoamine oxidase, cyclic AMP phosphodiesterase and dopamine-beta-hydroxylase.

The three dissimilar structural antidepressant drugs, imipramine, nomifensine and d-amphetamine, were compared for their effects on type B monoamine oxidase, cyclic AMP phosphodiesterase and dopamine-beta-hydroxylase. Three antidepressant drugs caused a dose-dependent inhibition on type B monoamine oxidase. Of the three drugs, imipramine had a most potent effect. Unlike d-amphetamine, both imipramine and nomifensine inhibited the cyclic AMP phosphodiesterase activity at concentrations more than 10(-4)M. No effect was observed below this concentration. All drugs seemed to have little or no effects on the partially purified dopamine-beta-hydroxylase activity. The weak inhibitory effects of nomifensine on these three enzymes may not be attributable to its antidepressant properties. Morphine had no effect on the three enzyme activities.