Abstracts

Rationale: It is well known that periventricular leukomalacia (PVL) is sometimes associated with West syndrome (WS). However, other types of epilepsy related to PVL have not been documented sufficiently. The Aim of this study is to clarify the clinical features of symptomatic localized-related epilepsy (LRE) in patients with PVL. Methods: We retrospectively studied 119 patients who fulfilled the following conditions; 1) spastic diplegia requiring habilitation, 2) PVL diagnosed by MRI, 3) aged 7 years or older at the last follow-up. The definition of PVL on MRI is both ventriculomegaly with irregular margin and periventricular high intensity areas on T2 weighted image. The severity of PVL was divided into three groups (mild, moderate, and severe PVL) according to the extent of the brain lesions. Mild PVL was defined as lesions localized in the trigonal zone, moderate PVL as those around the bodies and trigones of the lateral ventricles, and severe PVL as those extending around the anterior horn of the lateral ventricles. Among these patients, 9 patients had additional MRI findings such as post-hemorrhagic porencephaly and parasaggital infarction, and were excluded from the study. Among the eligible 110 patients, 15 patients had WS, 22 had epilepsies other than WS, and 73 had no epileptic seizures. All 22 patients with epilepsies other than WS had partial seizures with motor symptoms and were diagnosed as having LRE. Results: The median age of onset of LRE was 4 years and 4 months (range, 1 year to 12 years and 10 months). The age of onset was within 2 years in 4 patients, 3 or 4 years in 10, 5 to 10 years in 5, and older than 10 years in 3. The mean follow-up period from the first seizure was 10 years. Ten patients had a past history of febrile convulsions. One patient had only simple partial seizures and the others had complex partial seizures. Five patients had autonomic symptoms such as ictal vomiting and nausea. Eight had secondarily generalized seizures. The interictal electroencephalography commonly revealed spikes and/or spike-waves in the parietal, temporal, and occipital areas, although frontal-dominant spikes, multifocal spikes, and diffuse irregular spike-waves were observed in some patients. Among those with West syndrome, PVL was moderate in 4 patients and severe in 11, whereas it was mild in 7 patients, moderate in 9, and severe in 6 among those with LRE. Severe PVL was more frequent in patients with West syndrome than in those with LRE (p<0.01). At the last follow-up, 10 patients had no antiepileptic drug, 6 had one drug, and 6 had two drugs. Seven patients had never received antiepipetic treatment. The number of seizures after antiepileptic treatment was 0 in 3 patients, 1 in 4 patients, and more than 5 in only 3 patients. Conclusions: We considered that LRE associated with PVL were characterized by infrequent seizures and relatively favorable seizure outcome. The severity of PVL was milder in patients with LRE than in those with WS. Intense antiepileptic treatment will not be necessary for patients with LRE associated with PVL.