Several problems concerning the clinical electroencephalography (EEG) of epilepsy were discussed.
1) The incidence of epileptic discharge is required to be as high as possible for the effective use of EEG. The incidence rate of epileptic discharge at the first EEG is 75.3% and the cumulative incidence rate after the third EEG is 92.3% in childhood epilepsy. In adult epilepsy, the incidence rates are about 50% and 80% respectively.
2) Specific EEG findings for different types of epileptic syndromes are rare. The majority of epilepsies show nonspecific EEG abnormalities. Therefore, it is important to analyse the nonspecific findings and to utilize them not only for clinical practice but epilepsy reseach.
3) An electrically silent seizure is an uncommon condition in which differential diagnosis is difficult to diagnose from a nonepileptic paroxysmal phenomenon.
4) EEG patterns suggesting a convulsive predisposition may be used for the etiological classification of epilepsy.
5) The treatment of epilepsy should be carried out referring to the EEG findings. However, the degree of the condition of epilepsy may not be reflected in EEG findings in such cases as frontal lobe epilepsy, mesial temporal lobe epilepsy or a variant type of severe myoclonic epilepsy in infancy.

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Purpose: To evaluate the usefulness of dipole tracing method with realistic head model, we examined the locations of equivalent current dipole (ECD) around the organic lesion cases.
Subjects and Method: Five organic lesion cases were evaluated in this study. For the accuracy of data, we used dipole tracing method of realistic head model with inhomogeneous electrical conductivity, superimposed ECD over the realistic head model (ECD, dipolarity>0.98), and calculated the ECD concentration around the lesion.
Results: Most of ECDs were located around the lesion in all cases. The ECD concentration ratio was ranged from 70 to 90% within 20 mm around the lesion.
Neuroimaging examination showed clear margin of the organic lesion, a correlated to the scalp EEG showed spikes from the electrodes located near the lesion. Based on these preoperative evaluations, the organic lesion was totally resected. Four patients have been seizure free, and one patient has had seldom seizure after the operation (mean follow-up term 25 month).
Conclusions: Dipole tracing method of a realistic head model appeared to be useful to estimate the epileptogenic zone. Seventy percent of ECDs within an area 20 mm apart from the lesion are necessary, provided neuroimaging and scalp EEG, concordant results are found, there0fore, epilepsy could be controlled by a simple lesionectomy.

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We recorded simultaneously magnetoencephalogram and electroencephalogram and analyzed equivalent current dipoles (ECDs) of rolandic discharges (RDs) in 5 patients with benign childhood epilepsy with centrotemporal spikes (BECT). In addition to ECDs localization, we studied the current moment (Q) of ECDs, which reflects the size of synchronously active neuronal population. The distribution of the Q of 441 RDs was examined and compared with that of 512 spike discharges of nine age-matched patients with symptomatic partial epilepsy (SPE). Although the raw data of the Q was not normally distributed, the distribution after the logarithmic conversion revealed a normal distribution in both BECT and SPE. Consequently, the mean non-logarithmic Q value of RDs was 272 nAm (mean±SD 144-514 nAm) and that of spike discharges was 177 nAm (mean±SD 109-286 nAm). The Q of RDs was significantly larger and more widely distributed than that of spike discharges in SPE. Moreover, the Q of RDs markedly decreased in a relatively short period of time with cessation of the seizure. In conclusion, the RDs would be likely to originate from highly synchronous activity of more numerous and more changeable neuronal populations compared with the spike discharges in SPE.

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In order to evaluate the effect of ethyl loflazepate (LOF), we performed a clinical and electroencephalographic study on patients with childhood refractory epilepsy.
We investigated the effect of LOF add-on therapy on clinical seizures and EEGs as well as side effects in 41 patients, ranging in age from 3 months to 23 years 6 months. The patients were treated with LOF for at least three months.
LOF had marked or moderate effects in 25 patients (60.9%). However, in 11 patients, these effects were transient and disappeared within the first three months. LOF was more effective for symptomatic generalized epilepsy than other types of epilepsy. LOF was most effective for brief tonic seizures or tonic seizures. Epileptic discharges were suppressed or decreased in five of 14 patients who responded well to LOF. The maximum dose was well correlated with blood level (R=0.691). Twenty patients (49%) showed mild side effects, such as sleepiness and hypersalivation.

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A male with a ring chromosome 20 presenting with non-convulsive status epile-pticus (NCSE) was diagnosed to have a higher cerebral dysfunction by means of a neuropsychological test battery. He developed complex partial seizures at the age of 9 years, and since the age of 11, he has had daily episodes of NCSE, not responsive to medication. At the age of 18, he was identified as having a ring chromosome 20 [46, XY, r (20) (p13, q13)]. While being monitored by EEG-VCR, he was examined by a neuropsychological test battery, including tests for spontaneous speech, auditory verbal comprehension, repetition, naming on visual confrontation, reading, and one-and two-digit calculation. Comparing the results with those obtained during the interictal states, we identified his poorer ability of spontaneous speech and one- and two-digit calculation during the ictal state. On the other hand, repetition was intact during both the ictal and interictal states. The discrepancy between the poor spontane-ous speech and the good repetition led us to conclude that this ictal state was similar to transcortical motor aphasia. Involvement of the medial frontal lobe, in particular, the supplementary motor areas, was considered to be responsible for the poor calcula-tion ability.

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We present a case of symptomatic generalized epilepsy with gynecomastia. The patient had frequent axial tonic seizures and several global tonic seizures in a day. Interictal EEG showed bilateral slow spike and wave discharges. After an epileptic seizure, serum FSH levels didn't increase, but serum LH, PRL and E 2 levels increased. The seizures were reduced by VPA, and then gynecomastia resolved gradually. Consequently, we suggest that frequent epileptic seizures contributed to the gynecomastia by ictal pulsatile hormonal changes.

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