Although ectopic tissue in certain regions of the brain has been linked to epilepsy, a recent review of the literature concluded that periventricular nodular heterotopia rarely causes clinical seizures. The review evaluated chronic invasive EEG recordings and found that nodules alone are rarely responsible for seizures. Their onset is more likely to be connected with overlying neocortex or mesial temporal structures. However, the analysis did find that substantial or complete ablation of nodules usually results in more favorable surgical outcomes.
Thompson SA, Kalamangalam GP, Tandon N. Intracranial evaluation and laser ablation for epilepsy with periventricular nodular heterotopia. Seizure. 2016;41:211-216.