Trephine epilepsy surgery: the inferior temporal gyrus approach.

Abstract

To describe our technique for temporal lobe epilepsy surgery using a minimal-access approach. Our epilepsy surgery registry was reviewed, and all patients with at least 2 years follow-up were queried. Clinical data included age, sex, side of lesion, presence of mesial temporal sclerosis, surgical complications, and Engel class outcome. Our operation was performed through a 6- to 8-cm linear vertical incision extending upward from just anterior to the tragus. An oval trephine (2 x 3 cm) craniotomy was performed flush with the middle fossa floor. Resection of part of the inferior temporal gyrus provided a corridor to the mesial temporal lobe. Identification of the temporal horn of the lateral ventricle was followed by resection of the parahippocampal gyrus, the amygdala, and the uncus. Segregation of the hippocampus and its subsequent resection in subpial fashion preserved perimesencephalic vasculature. Use of a fine suture for skin closure produced a cosmetic result. In our 8-year series of 201 patients with a minimum follow-up duration of 2 years, we have observed a low number (1.5%) of complications and a 78% rate of Engel Class I seizure-free outcome. Surgery times were short (average, 2-5 h; range, 2 h 20 min-4 h 10 min) and hospital stays brief (<3 d; range, 1-4 d). Our results suggest that the trephine craniotomy with the inferior temporal gyrus approach has the advantage of minimal invasiveness, including brief operative times and postoperative stays, and also effectively reduces or eradicates medically intractable seizures.