Amygdalohippocampotomy for mesial temporal lobe sclerosis: Epilepsy outcome 5 years after surgery

The goal of the present study is the evaluation of the long-term clinical outcome of epilepsy in patients with mesial temporal lobe sclerosis (MTLS) submitted to amygdalohippocampotomy (AHCo). AHCo consists of the lateral ablation of the amygdala and the peri-hippocampal disconnection instead of amygdalohippocampectomy (AHC), which involves the removal of both structures. We previously reported the short-term results of AHCo, so we here present the long-term results (> 5 years of follow-up) of the patients operated on with AHCo.

Since 2007, 35 patients (22 females) aged 20-61 years (mean: 42 years) were operated on with the AHCo technique, 17 patients on the left side and 18 on the right. Of these patients, 21 (14 females) have been followed up > 5 years (5 to 7.5 years, mean 6.5 years). We compare the present results with those observed shortly after surgery and with the patients operated on with AHC.

In all 21 cases, the diagnosis was mesial temporal lobe sclerosis (histology confirmed in 20), 11 on the left side and 10 on the right. Epilepsy results after 5 years were good/very good in 18 patients (85.7%), with Engel class IA-B in 15 (71.4%) and II in 3 (14.3%), and bad in 3 patients, with Engel Class III in 2 (9.5%) and class IV in 1 (4.8%). Concerning morbidity, one patient had hemiparesis (hypertensive capsular hemorrhage 24 h after surgery), two verbal memory worsening, two quadrantanopia and three late depression that was reversed with medication. Comparatively, the AHC long-term results were 87% Engel class I, 8% Engel class II and 5% Engel class III-IV. The morbidity was equally small.

The good/very good results of AHCo 5 years after surgery are 86%, which is not distinct from the AHC results. So AHCo seems to be effective and potentially safer than AHC in long-term follow-up.