Amygdalohippocampotomy: surgical technique and clinical results

Abstract

The removal of mesial temporal structures, namely amygdalohippocampectomy, is the most efficient surgical procedure for the treatment of epilepsy. However, disconnection of the epileptogenic zones, as in temporal lobotomy or, for different purposes, hemispherotomy, have shown equivalent results with less morbidity. Thus, authors of the present study began performing selective amygdalohippocampotomy in cases of refractory mesial temporal lobe epilepsy (TLE) to treat mesial temporal lobe sclerosis (MTLS). The authors conducted a retrospective analysis of all cases of amygdalohippocampotomy collected in a database between November 2007 and March 2011. Since 2007, 21 patients (14 males and 7 females), ages 20-58 years (mean 41 years), all with TLE due to MTLS, were treated with selective ablation of the lateral amygdala plus perihippocampal disconnection (anterior one-half to two-thirds in dominant hemisphere), the left side in 11 cases and the right in 10. In 20 patients the follow-up was 2 or more years (range 24-44 months, average 32 months). Clinical outcome for epilepsy 2 years after surgery (20 patients) was good/very good in 19 patients (95%) with an Engel Class I (15 patients [75%]) or II outcome (4 patients [20%]) and bad in 1 patient (5%) with an Engel Class IV outcome (extratemporal focus and later reoperation). Surgical morbidity included hemiparesis (capsular hypertensive hemorrhage 24 hours after surgery, 1 patient), verbal memory worsening (2 patients), and quadrantanopia (permanent in 2 patients, transient in 1). Late psychiatric depression developed in 3 cases. Operative time was reduced by about 30 minutes (15%) on average with this technique. Amygdalohippocampotomy is as effective as amygdalohippocampectomy to treat MTLS and is a potentially safer, time-saving procedure.