FOCAL EPILEPTIC MYOCLONUS IN KOZHEVNIKOV–RASMUSSEN SYNDROME

Abstract

The article presents the clinical, electroencephalographic (EEG) and neuroimaging features, as well as the results of treatment of patients with focal epileptic myoclonus (FEM) with the Kozhevnikov–Rasmussen syndrome (KRS). FEM in KRS-patients was identified in 11 cases, accounting for 0.9 % of all the cases of epilepsy with the onset of seizures up to 18 years (n = 1261). The age at onset of KRS ranged from 3 to 21 years (average – 9.2 ± 5.7 years). In the active period of the disease of all patients in the clinical picture the active FEM appeared and increasing frequency of the secondary generalized seizures (SGS). In addition SGS and FEM, the clinical picture of the disease in most patients (91 %) the focal motor (clonic) and the somatosensory focal seizures were observed. As the disease progressed, the FEM became more pronounced in frequency and intensity, seized more muscle groups, localizing mainly in the muscles of the trunk and limbs. The typical EEG pattern of FEM patients with KRS was regional epileptiform activity that occurs in the structure of the continued regional slowing localizing maximum of the fronto-central-temporal region. During the magnetic resonance tomography of the brain in dynamics all the patients observed the increase in total cortical hemiatrophy. In all the cases, the appointment of antiepileptic therapy resulted in a slowing of the FEM, however, a complete remission was reached at none of the patients. Two patients were made surgical treatment of epilepsy. In one case remission of epileptic seizures was observed after right-side hemispherotomy. Our study showed that FEM is very resistant type of epileptic seizures. This fact calls for the identification of the FEM at the early stages of the disease with the purpose to improve the prognosis, as well as for an earlier surgical treatment.