Foramen ovale electrodes in the evaluation of epilepsy surgery: Conventional and unconventional uses

Foramen ovale (FO) electrodes have been used in the evaluation of epilepsy surgery for more than 25 years. Their traditional application was in patients with mesial temporal lobe epilepsy. Due in part to advances in neuroimaging, their use has declined. We describe our cumulative experience with FO electrodes and use examples to illustrate a range of indications for FO recordings that extend beyond their conventional utility for mesial temporal lobe cases. We also summarize the pros and cons of FO electrodes implantation and attempt to reestablish their utility in presurgical evaluation.

► Foramen ovale electrodes (FO) have traditionally been used in patients with mesial temporal lobe epilepsy. ► We describe our experience with their use beyond their conventional utility. ► In 5 years we performed 22 implantations that guided treatment with a small complication rate. ► FO may assist diagnosis of lateral temporal & extra-temporal epilepsy, epileptic pseudodementia, & nonepileptic seizures.