The Clinical Spectrum of Malformations of Cortical Development in a Cohort of Bulgarian Patients

Malformations of cortical development (MCD) are a heterogeneous group of diseases, that cause epileptic seizures, motor deficit and mental retardation. We analysed the clinical course, seizure characteristics and neuroimaging data in patients with cortical malformations, treated between 2006 and 2021 in the Clinic of Child Neurology of MHATNP “St. Naum”. We studied 205 patients with MCD, 94 girls (45.9%) and 111 boys (54.1%), with a mean age of 7.7 years, ranging from one month to 18 years of age. Ac- cording to the type of cortical malformation, patients were divided into five groups: 31 patients (15.12%) with heterotopia, 52 (25.3%) – with polymicro- gyria, 47 (22.9%) – with lissencephaly, 59 (28.9%) – with cortical dysplasia and 16 (7.8%) – with schizencephaly. Ninety-five (46.3%) of our patients were with intellectual disability. Mo- tor deficit was reported in 122 children (59.5%) and 173 patients (84.4%) had epileptic seizures. The seizures were focal in 42 (20.57%) of the cases, with mo- tor manifestation in 20 and secondary generalisation – in 7 of them. Forty-six patients experienced generalised seizures. Mixed type of seizures were regis- tered in 83 patients. In two children, the seizures could not be classified. The seizures frequency varied significantly, but patients with cortical dysplasia had the highest rate of daily seizures – 52.5% (n = 31), followed by patients with polymicrogyria – 25% (n = 13). Malformations of cortical development are a heterogeneous group of dis- orders, associated with mental retardation, epilepsy and motor deficit in childhood. Our study provides phenotypic information that would be useful for future genotype-phenotype correlations.