Neurológia pre prax 1/2012

Subcortical band heterotopia of the cerebral cortex with pharmacoresistant epilepsy

Subcortical laminar heterotopia of the cerebral cortex, also referred to as band heterotopia (BH) or double cortex, is a rather rare developmental defect of the cerebral cortex characterized by the presence of large bands of grey matter below the surface of the cortex. This malformation occurs mostly in women and is manifested as sporadic or familial cases with epilepsy and varying degrees of mental retardation. The most common cause of the disease is a mutation in the doublecortin gene, resulting in BH in females and, predominantly, in agyria-pachygyria and, only sporadically, in BH in males. Two female patients were followed for delayed psychomotor development and pharmacoresistant epilepsy with partial seizures with occasional secondary generalizations. Magnetic resonance imaging of the brain showed a typical presentation of BH. Multiregional epileptiform activity with an occasional generalized epileptiform pattern was recorded on electroencephalography (EEG). An ictal pattern with secondary generalized epileptiform activity was repeatedly detected during video-EEG monitoring. During many years of follow-up of the patients, a number of antiepileptic drugs and their combinations have been tried. Due to comprehensive evaluation, including video-EEG monitoring and an analysis of drug history, it has been possible to optimize the treatment with antiepileptic drugs and even to discontinue some of them. In one of the patients, treatment with vagus nerve stimulation was indicated, which resulted in a significant reduction in atonic and in myoclonic seizures. In terms of pharmacotherapy, BH is a very challenging area for an epileptologist, with a need for combined therapy using antiepileptic drugs with their potential interactions and side effects; the possibilities for successful epilepsy surgery are largely limited in this case. With that said, a certain hope of at least some improvement for these patients remains in VNS treatment or palliative anterior callosotomy.

Keywords: band heterotopia, double cortex, pharmacoresistant epilepsy, mental retardation.