Comparison of classifications of seizures: a preliminary study with 28 participants and 48 seizures.

PURPOSE: Our aim was to compare three available seizure classifications (SCs), namely, the international classification of epileptic seizures published in 1981 (ICES; Epilepsia 1981;22:489-50); the semiological seizure classification (SSC) by H. Luders, J. Acharya, C. Baumgartner, et al. (Epilepsia 1998;39:1006-13; Acta Neurol Scand 1999;99:137-41); and the proposal of a new diagnostic scheme for seizures (PDSS) by J. Engel, Jr. (Epilepsia 2001;42:796-803) published in 2001. The three SCs were compared with respect to diagnostic success rates, usefulness, and consistency by a large group of neurologists in this preliminary study. METHODS: After a training period, 28 blindfed participants with different levels of experience with epilepsy classified videos or written descriptions of 48 randomly selected seizures according to the three SCs. Definite diagnoses of the seizures were established based on all clinical, ictal/interictal EEG, and MRI data. All the participants answered a questionnaire concerning their preferences for SCs after the study. RESULTS: The overall diagnostic success rates were 81.4% for ICES, 80.5% for PDSS, and 87.5%, for SSC. Various parameters concerning experience with epilepsy affected success rates positively, without reaching statistical significance, whereas experience with epilepsy surgery appeared to be a parameter significantly affecting the success rate in all SCs. In reliability analysis, Cronbach's alpha was 0.94 for ICES, 0.88 for PDSS, and 0.70 for SSC, all showing good agreement in the group. Nineteen reviewers chose SSC, eight chose ICES, and one chose PDSS as their preference in the questionnaire, completed after the end of the study. CONCLUSION: The results of this preliminary study demonstrate that with proper training, physicians treating epilepsy patients can handle new SCs, and emphasize the need for revision of the current classification.

Decreased motor unit number estimates in juvenile myoclonic epilepsy.

In this study, motor unit number estimate (MUNE) analysis with McComa's technique was used to detect any change in lower motor neuron count in juvenile myoclonic epilepsy (JME). The study included 10 JME patients, 8 idiopathic generalized epilepsy (IGE) patients, 7 patients with mesial temporal sclerosis (MTS), and 15 normal subjects. All the patients and normal subjects were subjected to MUNE analysis on the abductor pollicis brevis and tibialis anterior muscles, as well as needle electromyography and nerve conduction studies. Electromyographic and nerve conduction studies were normal in all groups. MUNEs in the JME group and were significantly lower than those of normal subjects (P < 0.001). MUNEs of IGE and MTS patients also tended to be lower than that of normal subjects with no significant difference from normal subjects. MUNEs of abductor pollicis brevis and tibialis anterior muscles were 114 +/- 24 and 90 +/- 15 for normal subjects, 59 +/- 18 and 50 +/- 23 for JME patients, 91 +/- 22 and 75 +/- 19 for IGE patients, and 84 +/- 42 and 80 +/- 29 for MTS patients respectively. It may be reasonable to suggest that a genetic origin is responsible for a tendency to contract epilepsy, and the disorganization of lower motor neurons may be shared in JME.