Variabilità clinico-elettroencefalografica in pazienti con malformazione dello sviluppo corticale tipo polimicrogiria bilaterale

Polymicrogyria (PMG) is a malformation of cortical organization. There is a wide spectrum of clinical manifestation in patients with PMG, varying from severe encephalopathy, mental retardation and refractory epilepsy to selective cognitive impairment. We report 4 cases of bilateral PMG (2 cases of bilateral frontal PMG and 2 cases of bilateral perisylvian PMG), with significant differences in clinical and EEG characteristics. 2 patients (1 with frontal localization ad 1 with perisylvian localization) had epilepsy associated with Electrical Status Epilepticus during slow sleep (ESES) and Focal Electrical Status. The other patient with bilateral frontal PMG presented seizures associated with photosensitivity and paroxysmal episodes of "alternating hemiplegia". The other case of bilateral perisylvian PMG had focal seizures without EEG abnormalities during sleep and awake. For all patients we performed genetic exams (high resolution kariotype, GPR56, FISH 22q11), resulting negative in all patients. Our data confirm the large variability of clinical and EEG features in patients with similar cortical malformation.