gms | German Medical Science

Objective: Mesial temporal lobe epilepsy (MTLE) is the most common cause for refractory epilepsy. There is no doubt that resective mesial temporal lobe surgery (rMTLS) has proven to be an effective method of treatment to provide good results in regard to seizure control. However, several different surgical approaches to the mesial temporal lobe structures are used. The aim of this study was to report on surgical treatment of patients with MTLE using the transsylvian selective amygdalohippocampectomy (tsSAHE).

Methods: Patients with MTLE who underwent tsSAHE between 2012 and 2017 were reviewed from the epilepsy surgery database at our center. All patients were presurgically assessed in the department of epileptology and were considered to be suitable for surgery. The surgical procedures of tsSAHE were performed in a highly standardized fashion. The analysis of clinical, radiological, histopathological and perioperative findings was performed. The postoperative seizure outcome was assessed according to ILAE-Classification at 1 year after surgery. The multivariate regression analysis was performed for identification of independent risk factors for unfavorable post-op. seizure outcome (ILAE Class ≥2).

Results: Among all patients who underwent rMTLS during the study period, 103 patients were operated using tsSAHE. The mean age at epilepsy onset was 17y±13. The mean epilepsy duration was 21.9y±14.1. Out of 91 patients with completed 1-year-follow-up, 67(73.6 %) were seizure free (ILAE Class 1). Surgical site complications occurred in 6(6%) patients. In 3(3%) patients surgical revision was required. The hippocampal sclerosis (HS) was the most common histological diagnosis [85(83%)] followed by hippocampal gliosis [15(14%)]. The multivariate analysis revealed the absence of HS (OR 5.6; CI 1.7–18.45; p=0.004) and incomplete resection (OR 14.75; CI 1.4–154.1; p=0.025) as significant and independent risk factors for unfavorable seizure outcome.

Conclusion: Transsylvian selective amygdalohippocampectomy provides high rates of seizure control in patients with MTLE. The occurrence rate of surgical complications is low. However, patients without evidence of HS and patients with incomplete resection of temporomesial structures have a higher risk for unfavorable seizure outcome.