Technical Modification of Amygdalo-Hippocampectomy in Temporal Lobe Epilepsy Surgery to Further Reduce Severe Neurological Complications: A Clinical-Anatomical Study.

BACKGROUND

Temporal lobe resection (TLR) including amygdalohippocampectomy (AHE) is the most frequent performed procedure in epilepsy surgery. Owing to the close anatomic relationship of the mesial temporal structures and the midbrain and choroidal fissure, the incidence of severe complications, such as postoperative stroke, is as high as 2.5%.

METHODS

We developed a modification of the classical technique for AHE that involves entering the choroidal fissure early via the anterior part of the frontomesial temporal horn cleft to identify the crus cerebri, posterior cerebri artery, and oculomotor nerve. In a second step, after visualization of the cleavage plane between the midbrain and middle cerebral artery, the uncus and amygdala are removed.

RESULTS

A total of 81 patients (47 females and 34 males; mean age at surgery, 40 years) underwent TLR including AHE with our surgical modification to treat heterogeneous pathologies. The cohort included 45 patients with hippocampal sclerosis, 11 with ganglioglioma, 2 with dysembryoplastic neuroepithelioma, 2 with diffuse glioma, and 21 with other pathologies, including cavernoma, scar tissue, and mild cortical dysplasia, among others. In all patients, anterior temporal resection was performed via AHE using our modified technique. Seizure outcome was favorable after a mean follow-up of 27 months (range, 3-56 months); 64% of the patients were completely seizure-free (Engel class 1A), and 75% had an Engel class 1 outcome. There was no mortality or permanent severe neurologic complications, and the rate of surgical complications was 3.7%.

CONCLUSIONS

Our modified AHE technique is associated with a low rate of complications in TLR for medically refractory temporal lobe epilepsy, and helps avoid permanent severe neurologic complications.