Polymicrogyria and epilepsy with continuous spike-wave during sleep in pediatric patients

Objective: to evaluate the course of epilepsy with CSWS in pediatric patients with polymicrogyria (PMG). Methods: We examined 15 patients (8–females, 7–males) with PMG using night EEG: 4 with bilateral (2–bilateral perisylvian; 2–bilateral frontoparietal) and 11 with unilateral PMG (5–frontoparietal, 1–parieto-occipital, 5–perisylvian). Results: CSWS (>50%) was revealed in 10(66.7%) cases: in 3(30.0%)–unilateral, in 7(70.0%)–regional with secondary bilateral synchronization. 2(20.0%) had bilateral PMG (1(10.0%) frontoparietal and 1(10.0%) perisylvian), 8(80.0%) – unilateral (4(40.0%) – frontoparietal, 3(30.0%) – perisylvian, 1(10.0%) - parieto-occipital). 9(90.0%) patients had epileptic seizures. The age of epilepsy onset – 2.27±1.29. The type of seizures: 1(11.1%) – infantile spasms, 8(88.9%) – focal, 2(22.2%) – bilateral tonic-clonic, 6(66.6%) – myoclonic, 2(22.2%) – tonic, 1(11.1%) – atonic. Cognitive impairments were in 7(70.0%) cases: mild - in 4(40.0%), moderate - in 3(30.0%). 6(60.0%) patients had deterioration in intelligence after the epilepsy onset. Motor disturbances were in 7(70.0%): in 6(60.0%) - GMFСS II, in 1(10.0%) - GMFCS III. Drug-resistant epilepsy was in 8(88.9%) cases. At the last visit the age of patients was 12.8±5.8. Only 1(11.1%) had been seizure-free for more than one year using antiepileptic drugs. VNS was implanted in 4(44.4%) cases. 2 years later the efficiency was: 2(50.0%) - reduction in seizures frequency by 75-100%, 2(50.0%) - by 0-25%. Conclusion. CSWS is a common EEG pattern in both unilateral and bilateral PMG. In almost all the cases, epilepsy with CSWS had a drug-resistant course and seizures continued at the time of the last visit.
Keywords: polymicrogyria, epilepsy, CSWS.