gms | German Medical Science

Objective: Temporal lobe surgery including amygdalo-hippocampectomy (AHE) is the most frequently performed procedure in epilepsy surgery. Due to anatomical relationships of the mesial temporal structures and the midbrain and choroidal fissure, the risk of severe complications like postoperative stroke is up to 1-2.5%.

Methods: We developed a modified subpial "en bloc" resection technique for removing the hippocampus and parahippocampal gyrus by early identification of crus cerebri, posterior cerebri artery and oculomotor nerve through the ventricle via the anterior part of the fronto-mesial temporal horn cleft. Uncus and amygdala were removed in a second step after visualization of the cleavage plane between the midbrain and the middle cerebral artery.

Results: Altogether 81 patients (47 females, 34 males, mean age 40 years at surgery) had temporal lobe epilepsy surgery using this surgical technique for heterogeneous pathologies including AHE using this surgical technique (45 hippocampal sclerosis, 11 ganglioglioma, 2 dysembryoplastic neuroepithelioma (DNET), 2 diffuse glioma 21 other pathologies like cavernoma, scar tissue or mild cortical dysplasia). All patients had anterior temporal resection including AHE. Seizure outcome was favorable after a mean follow-up of 27 months: 64% were completely seizure free (Engel Class 1A) and 75% had Engel Class 1 outcome. There was no mortality, 0% permanent severe neurological and 3.7% surgical complications.

Conclusion: The newly described subpial modified "en bloc" resection technique for AHE was found to have low complication rates in surgery of medically refractory temporal lobe epilepsy. Special attention is devoted to avodingd permanent hemiparesis.