Toshiaki Ninchoji

Low frequency stimulation induces an increase in after-discharge thresholds in hippocampal and amygdaloid kindling

In rats with electrodes implanted in the hippocampus or amygdala, the effect was studied of a single episode of low frequency stimulation (125 msec, biphasic 4 Hz, for 1 min at a current 50% of threshold for after-discharge), LFS, on the after-discharge thresholds (ADTs) during the course of hippocampal and amygdaloid kindling. ADTs were significantly increased following the LFS. The effect lasted longer (hippocampus, 12 days; amygdala, 5 days) when the LFS was given on day 1 of kindling than when kindling was fully established (less than 24 h).

Epidermoid tumor in the fourth ventricle, with particular reference to metrizamide ct cisternography findings

The case of an epidermoid tumor in the fourth ventricle is presented, in which metrizamide computed tomographic (CT) cisternography was carried out. Unique features shown in the study might be specific to this lesion in this particular location. Clinical correlation of this finding was made with those findings seen at the operation.

Effect of pinealectomy on cortically kindled rats

Cortical kindling in pinealectomized rats was studied to observe the effect of pinealectomy on local afterdischarge thresholds and seizure development. Although the local afterdischarge thresholds were not affected by pinealectomy, the kindling process itself was hastened. These results suggest that the anticonvulsive function of the pineal body is due not to a decrease in local afterdischarge thresholds, but to retardation of secondary generalization.

A case of congenital absence of the left internal carotid artery

A case of congenital absence of the internal carotid artery was presented in a 37-year-old male with temporal lobe epilepsy. A dilated vascular channel, which is one of the characteristics associated with the congenital absence of the internal carotid artery, can be demonstrated in the conventional contrast-enhanced CT scans. Absence of the carotid canal can be delineated far more clearly in the CT scans of the skull base.

LINE-DRAWING TEST ACROSS AGES '"

A line-drawing test was standardized for normal subjects to examine effects of normal aging. For this purpose, the results of the test for 168 normal volunteers were quantified using a digitizer and a microcomputer across ages from 9 to 78 yr. Three sets of parallel vertical lines were presented to every subject, the distances between the parallel vertical lines (5. 10, and 15 cm) differed in the three sets. A subject drew an horizontal line starting exactly on the left vertical line and stopped exactly on the right one, and the computer could detect minute inaccuracy at the start and at the stop, which inaccuracy was expressed in mm. In this study, effects of four parameters were evaluated, i.e., ages, sex, distances from the paired vertical lines, and order of trials; all were nonsignificant. The normal range of the deviations was within 2.1 mm (average + 2 SD).