The etiology of the Lennox-Gastaut syndrome (LGS) and its relationship to clinical manifestation and prognosis were studied in 125 cases: 30 (24.0%) cryptogenic cases and 95 (76.0%) symptomatic cases
The mental prognosis was significantly more favorable in the cryptogenic group. There was no obvious difference, however, between the cryptogenic group and the symptomatic group in the prognosis for seizures. At the time of follow-up, the cryptogenic group was composed of 11 mentally normal cases (Group C-1) and mentally retarded cases (Group C-2). Seizure prognosis was significantly the best in Group C-1.
EEG topography showed an abnormal increase in the delta band activity in the frontal area in the symptomatic group and in Group C-2, but not in Group C-1. This EEG topography finding indicated the pathophysiological similarity of the symptomatic group to Group C-2, but not to Group C-1. This result was compatible with clinical findings, and it suggests that Group C-1 may be essentially idiopathic.
On the other hand, 50 cases evolving from West syndrome (WS) were significantly less favorable in both mental and seizure prognosis than the remaining 75 cases having no such evolution. Most of the 50 were symptomatic cases and had prenatal etiologies. These findings suggest that the evolution from WS to LGS is important in considering the prognosis of the LGS and that the evolutional change is also related to the etiology.

View full abstract

The MR imaging shows the intracranial lesions more exactly and gives us more effective figures of the brain than the CT scan, because of not only its ability to demonstrate fine imagings of structures but also the possibility to make the scanning with free slices.
Eleven cases with post-traumatic uncontrolable epilepsy, who had head injury in their infancy or childhood, were studied about the MR imagings and compared with their CT findings. The affected lesions mainly consisted of the cortical atrophy which was demonstrated by CT scan, but the MR imagings showed that the extent of atrophy was much larger than the extent demonstrated by the CT scan. Furthermore, the asymmetry of bilateral temporal lobes was demonstrated by the MR imagings of coronal slice through the temporal lobe in seven cases. The temporal lobe in the affected side was smaller than the non-affected side. The high intensity of medial side of the temporal lobe was also demonstrated in the T 2 weighted MR imaging.

View full abstract

We experienced a right handed case of reflex epilepsy induced by higher mental activity under a high mental tension, mainly by mental arithmetic and Soroban calculation.Clinical seizure induced by mental arithmetic was atypical absence without myoclonic jerk and that by Soroban calculation was myoclonic jerk on the right arm and fingers without loss of consciousness. On the EEG, a similar epileptic discharge which was generalized spike and wave discharge arising predominantly from left centro-parietal area occurred in both situations.

View full abstract

There have been some reports about the efficacy of the new antiepileptic drug, zonisamide, during recent several years. According to those reports, various types of refractory epileptic seizures respond to the administration of the new drug. However, they usually report only about short term administration of the drug.
Thirty-five patients including children who had been administered zonisamide for more than one year are reported.
Seven of them (20%) have been free from epileptic seizures for more than six months. On the other hand, eight of them (23%) showed only transient improvement, suggesting the development of tolerance to the drug. Most cases showed improvement from one week to several months after the administration. Because maximum effects appeared several years later in some patients, continuation of administration of the drug was considered to be important.The effective range of the plasma level of the drug was 4.1-46.3Junzou Shiraishi, g/ml and the effective dose was 2.4-17.5mg/kg.
All side effects were mild and transient.
Zonisamide is considered to be a safe antiepileptic drug with broad -spectrum of effects on refractory epilepsy.

View full abstract

Out of 412 epileptic in-patients treated in 1986 through 1989, the thirty patients who had had a past history of HH syndrome satisfying the definition of Gastaut (1959) were selected for this study. The purpose of this paper is to examine pathoplastic effects of primary lesions produced by initial HH syndrome on secondary epileptogenic lesions manifested clinically as epileptic seizures. The subjects were divided into three groups: those who had only temporal foci (TLE-group), those who had extratemporal foci and distinct clinical symptoms of partial seizure (PE-group), and those who had electroclinical manifestations of generalized seizure (GE-group). The results were as follows:(1) The interval between the HH syndrome and the secondary epilepsy was much shorter in GE-group (1.7±4.0 years) than in TLE-group (7.7±6.2 years)(2) The proportion of right hemiplegia is much higher in PE-group (63%) and GE-group (67%) than in TLE-group (38%):(3) Compared with control-group (51 patients with simple partial seizure and TLE and without HHE syndrome), TLE-group in our study was characterized by a high frequency of autonomic aura (54% v. 33%) and low frequency of anxiety aura (0% v. 18%) and illusion of familiarity (9% v. 25%).
Considering earlier onsets of epilepsy in PE-group and GE-group than in TLE-group (Table 2), high proportion of right hemiplegia in the former groups supported Ounsted's theory tht left hemisphere is more vulnerable in the early course of cerebral maturation. We suggested further that peculiar constellations of auras in TLE-group could be a characteristic of medial temporal lobe epilepsy.

View full abstract

In recent years, there has been great interest in the fact that the substantia nigra (SN) closely regulates the initiation and spread of epileptic motor seizures. However, it has not been elucidated which of the nigral efferent connections can influence the limbic motor seizures. To clarify this question, we studied the role of the GABAergic pathway from SN to pedunculopontine nucleus (PPN) in the amygadaloid seizure of rats. Microinfusions of a GABA antagonist, bicuculline, significantly suppressed the kindled seizures. Next, GABA concentrations in the caudate-putamen (CP), SN, and PPN of kindled rats were determined ty the O-phthalaldehyde method. The GABA concentration was significantly elevated in bilateral PPN, but there were no significant changes in the GABA concentration in CP and SN.
These results indicate that the GABAergic efferent from SN to PPN appears to be involved in the propagation of limbic motor seizures. The GABAergic neuronal activity between SN and PPN may be intensified in the kindling phenomenon, and this may result in the inhibition of the anticonvulsant function of PPN. Thus, the infusion of bicuculline into SN may disinhibit the neuronal activity of PPN and suppress the seizure propagation.

View full abstract

We report a case of medically intractable Lennox-Gastaut syndrome who was successfully treated with the anterior callosotomy. After he experienced status epilepticus at the age of 14 years, his seizures evolved generalized tonic-clonic seizure, atypical absence, drop attack, and myoclonus of both hands for following 21 years. Despite administration of various anticonvulsats, his seizures became more frequent. At the age of 35 years, he admitted our hospital. Preoperative EEGs showed diffuse slow spike and wave dominantly in the frontal, parietal and temporal regions. MRI was normal except for mild diffuse brain atropy. Anterior callosotomy was performed under monitoring of transcallosal response (TCR) by stimultion of the corpus callosum to identify the commissural fiber. During postoperative follow-up periods for 9 months, marked reduction of drop attack, atypical absence, and generalized tonic-clonic seizure was observed. Postoperative EEGs showed lateralization of slow spike and wave discharges to the right central region.
Intraoperative monitoring of TCR was useful method for identification of the caudal portion during partial callosotomy. Indication of the callosotomy and possible mechanism of the corpus callosum in epilepsy were discussed.

View full abstract

Ever since the Rodin' review on the prognosis of epilepsy appeared in 1968, it has been believed that the prognosis of epilepsy is generally poor, and that many patients with epileptic disorders need to take antiepileptic drugs for a lifelong period. In Japan, many practioners participating in the treatment of epilepsy also have been influenced by the traditionally pessimistic view. Recent studies, however, indicate that the prognosis of epilepsy is much more favorable than has been implied by the previous study. The authors tried to reduce gradually antiepileptic drugs when patiens have been free from seizures for more than two years and also epileptic discharges have disappeared during the period. During the reduction of medication, EEG recordings were repeatedly conducted to certify the disappearance of epileptic discharges. Using both the criteria and procedures the authors could discontinue antiepileptic drugs without the recurrence of seizures.
The authots reported 15 patients who had had seizures for many years but have been free from seizures following the withdrawal of medicaion. BECCT and typical abcence with 3 c/s spike and wave complexes were not included in the patients. Of the 15, 10 were patients with partial seizures and the remains were those with generalized seizures. The authors conclude from these data that some patients with chronic epilepsy can be withdawn from medications without relapse if therapists adopt suitable criteria and procedures.

View full abstract

We studied incidences of convulsive seizures in patients with cerebrovascular accidents, the lesion of which had originated in the cerebrum.
The results were as follows:
1) The incidences of immediate, early and late convulsions are 4.2%, 1.6% and 5.2%(7.5% in patients followed up for more than 2 years).
2) Occurrence of late seizures were adversely affected by
a) surgical procedures
b) hemorrhagic infarctions involving the cortex, and
c) immediate convulsions after infarction.
3) Patients with any kinds of operative procedures in both ischemic and hemorrhggic lesions showed a high tendency of late convulsions.
4) Most of late convulsions (92%) occurred within 2 years.
5) Presence of convulsions after cerebrovascular accidents did not have prognostic value for underlying brain diseases.

View full abstract

Recently much attention has been paid to neuropeptides as endogenous epileptic inhibitors and promotors. In order to examine the relationship between the development of epilepsy and somatostatin (SRIF), we examined the change of immunoreactive SRIF (IR-SRIF) in cerebrospinal fluid (CSF) and brain at each stage of progression in cat amygdaloid kindling model.
Twenty-five crossbred adult cats were divided into five groups; control group (C), sham operation group (S), stage 4 group (S4) and stage 6 group 2 days (S6-2d) or stage 6 group 2 weeks (S6-2w) after the last stimulation. CSF and 13 individual brain regions were acquired 9+4°C. IR-SRIF was meansured by radioimmunoassay.
IR-SRIF concentrations were significantly higher in the S6-2d group than those of the C group in CSF and several brain regions; left and right amygdala, piriform cortex, and right hippocampus. Those in the S 6-2 w group were also higher in CSF and several brain regions; left and right amygdala, piriform cortex and hippocampus.
Our results suggest that the change in endogenous SRIF may be involved in the development of epilepsy, especially during later stages, in amygdaloid kindled cat and IR-SRIF concentrations in CSF reflect the change of SRIF in the brain.

View full abstract

A follow-up study was carried out to determine the driving status in 99 epileptic patients (74 males and 25 females) who had held driving licences two years before.
Ninety-eight patients (99%) kept current driving licences, and 81 (83%) of them were actually driving motor vehicles at the time of this study. Sixty-two patients (63%) of the 98 licence holders had seizure-free period for the last five years or more. Fiftee patients (19%) of the 81 current drivers still had fits during the past two years.
Seven patients (7%) had caused traffic accidents, but no accident had occurred due to seizures. The form of seven accidents was as follows: one case of slight physical injury to the other person, 2 cases of the driver's own car damages without other material damages and 4 cases of accidents involving the other cars. There was no significant relationship between the accidents and seizure types.

View full abstract