Tetsuhiko Asakura

A Morphological Study on Vascular Changes in the Surgically Resected Tissues of Temporal Lobe Epilepsy—with a Special Reference to the Etiology

1 Twenty‐one out of 23 cases surgically resected specimens of TLE presented the common histological findings; sclerotic changes of the tissues. And the other two cases encountered the small tumors which might be called “cryptic.” 2 Since circulatory disturbance is generally accepted to explain the cause of TLE, we reexamined vascular behaviors in detail and found the quantitative and qualitative abnormalities which reached the high rate of 71% (17 out of 21 cases) except two cases of small tumors. Moreover, it is remarkably noteworthy that these vascular changes adjoin the sclerosed parenchymal tissue. 3 It may be said that vascular changes have exerted some influences on the formation of inferomedial temporal sclerosis from the standpoint of the histological findings, though they are alone not fully sufficient to explain the etiology of TLE.

Epileptogenic Focus and MRI—The Study of MRI and EEG of No Relation to Epileptogenic Focus

It is well known that the principal mean of investigating patients for epilepsy is EEG. However, this method is sometimes inadequate for detecting the epileptogenic focus. Magnetic resonance imaging (MRI) is a newly adopted technique which may be useful in the investigation of epileptogenic lesions, and was found to sometimes show greater sensitivity in the detection of focus than X-ray CT. The authors report herein that there may or may not be a close relation between MRI and EEG in the patients with epilepsy.

A Correlative Study between Hippocampal Atrophy Quantified by Tomo‐Pneumoencephalography and Epileptogenic Focus in Temporal Lobe Epilepsy

It appeared certain that we can quantify the rate of hippocampal atrophy by utilizing the sagittal cuts in tomo‐pneumoencephalog‐raphy. This is a reliable method to infer the side of the epileptogenic focus in temporal lobe epilepsy since a close correlation was disclosed between the side with more atrophic features of the hippocampus and that of the epileptogenic focus explored by depth EEG, in particular, in the mesial temporal focus group. On the other hand, it seems to be plausible that the hippocampal atrophy could be secondarily induced by epileptic discharges in the lateral temporal group. Namely, controversies dealing with the casual relationship of hippocampal atrophy should be discussed based on the epileptogenic focus localization in temporal lobe epilepsy.

A Morphological Study on MRI in 100 Patients with Epilepsy

In summary, this study suggests that MRI is an effective tool for imaging the epileptogenic lesions of the patients with epilepsy and the specified axial image is useful in the investigation of the temporal lobe structure.

Propagation of the Epileptic Discharge: Transverse or Longitudinal?

In order to establish the strategy of comprehensive treatment of epilepsy, it will be most necessary to understand the clinical manifestations produced by the propagation of epileptic discharge which spread intracerebrally from the cortex to the periphery via the spinal cord. The president of this meeting, Prof. J. Mukawa had asked us, the authors, to organize and also to take the chair of the symposium as titles. His strongest interests were based on whether the transverse propagation or the longitudinal propagation will play a major role, even if both mechanisms will intermingle with each other, in the actual seizures. The authors had requested to let contributions to this planning by two foreign investigators and seven domestic researchers. They were very cooperative and well responded to our requests.

Refractory Epilepsy: An Approach from Surgery

One hundred years have passed since Sir Victor Horsely first performed an operation for epilepsy at Queen Square in L0ndon.l The authors are greatly honored to consider the approach to refractory epilepsies from the standpoint of surgery in such a period. As the surgical treatment is not done by magic, refractory epilepsy is also difficult for surgeons to manage. Surgeons are handicapped because they are requested to treat epilepsies which are uncontrollable even with medical treatments. It is our honor to be left a legacy that can be beneficial for the treatment of refractory epilepsies, but at the same time heavy responsibility and pathetic resolution rest on us. If you don’t have an accurate knowledge about the pathophysiology and problem of your patients, the result will be nothing less than miserable. The authors will discuss the significance of surgical treatment of refractory epilepsy in this paper.

Small Ventricles detected by CT‐Scanning in Epileptic Patients

Relatively young 119 cases of generalized epilepsy and 99 controls of an identical age were selected. The bicaudate CVI was measured and the results were as follows: 1) In our cases, the mean of bicaudate CVI showed a smaller value than those of Hahns in both epilepsy and control groups. 2) When the value of bicaudate CVI was set up below the point of 8.5 as excessively small ventricle, the incidence rate of excessively small ventricle was 9% in the control group and 31% in the epilepsy group. The data showed higher incidences of small ventricles in the epilepsy group, and that the younger females have a tendency to have higher incidences of small ventricles. 3) To make clear the reason for the higher incidences of small ventricles in epilepsy, the small ventricle group and the non-small ventricle group in epilepsy were compared with each other from the points of the clinical course, EEG findings and frequency of attacks. No correlation or difference between them was found. Further investigation will be needed to make clear the etiology of small ventricles in epilepsy. However, it could be said at the present stage that not so many atrophic changes were observed in the younger patients of generalized epilepsy.

Experimental Studies on Facilitative and Inhibitory Factors for Epileptogenic Focus Formation

In recent years, several publications have dealt with the development of mirror foci and/or independent secondary epileptogenic lesions in frogs, rats, rabbits, cats and monkey^.^ l1 j 4 Id l0 Such studies have shown that propagation of the discharge takes place along certain pre-established pathways or connections of functional projection, such as from one motor zone to another via the corpus ca1losum.l Moreover, subcortical propagation occurs, such as from a cortical focus to the specific thalamic nuclei. Furthermore, an abnormal functional state was also found in the basal ganglia and in the thalamic nuclei and limbic structures. But it had seldom or never been discovered what the so-called constitutional predisposition to epilepsy in man causes. Wilder and Morrell have observed that the secondary epileptogenesis tended to occur in a shorter length of time in the brains on the lower evolutionary scale. The purpose of this paper is to study the facilitative and inhibitory factors for the secondary epileptogenic focus formation; namely through the investigation of such substances as eserin, atropine, safrazine and chlorpromazine, in the central nervous sys-