Abstracts

Rationale: Ictal onset in an isolated periventricular nodular heterotopia (PNH) has already been demonstrated in 1998 (Kothare et al., Neurology 1998;51:1723-1727). PNHs can be connected to the overlying cortex, so that lesionectomy and partial cortectomy seems to be an optimal therapeutic approach. However, this procedure has considerable limits in patients with adjacent functional eloquent cortex or with multiple PNH, so that a surgical procedure is oftentimes dismissed. Methods: We attempted a far less invasive approach with stereotactically guided thermoablation after ictal recordings with surface and depth electrodes suggested the epileptogenic zone at the isolated PNH. Postsurgical follow up was assessed every six months. Results: This 56-year-old otherwise healthy man experienced unspecific auras, clonic, aphasic, dialeptic and bilateral tonic-clinic seizures since the age of three. Before operation the seizure frequency was 1-2/day for the simple and partial seizures and 1/week for the grand-mal, respectively. After the surgical interventions there was one cluster of breakthrough seizures after accidental non-adherence to antiepileptic medication. Conclusions: We present a case with a favorable outcome after minimal invasive epilepsy surgery. Thermoablation should be considered in the case of concordant surface and stereo-EEG findings. For certain patients with multiple PNH, thermoablation could also be considered prior to resective surgery.