Abstracts

Short and Long-term Surgical Outcomes of Lateral Temporal Lobe Epilepsy: Exploring Reliable Prognostic Factors

Abstract number : 2.28
Submission category : 9. Surgery / 9A. Adult
Year : 2022
Submission ID : 2204012
Source : www.aesnet.org
Presentation date : 12/4/2022 12:00:00 PM
Published date : Nov 22, 2022, 05:23 AM

Authors :
Jae Rim Kim, MD – Samsung Medical Center; Eun Yeon Joo, PhD – Samsung Medical Center; Soo Ryun Park, MD – Samsung Medical Center

Rationale: Epilepsy surgery is a therapeutic option for patients with drug-resistant epilepsy. As lateral temporal lobe epilepsy (LTLE) is diagnosed in a small number of patients, its surgical outcome is not as well-known as mesial TLE. We aimed to evaluate the long- (5 years) and short- (2 years) term surgical outcomes and identify possible prognostic factors in patients with LTLE.

Methods: A retrospective cohort study was conducted between January 1995 and December 2018 among patients undergoing resective surgery in one university-affiliated hospital.

Results: Sixty-six patients were included. The mean follow-up duration after surgery was 8.2 years. Fifty-three (80.3%) patients were followed up for more than 5 years. Within 2 years after surgery, 40 of the 66 (60.6%) patients achieved seizure freedom. Within 5 years after surgery, 38 of the 53 (71.7%) patients achieved seizure freedom. Clinically and statistically significant prognostic factors for postsurgical outcomes were duration of epilepsy prior to surgery and focal cortical dysplasia on postoperative histopathology at the 5-year follow-up. At the 2-year follow-up, in addition to the two prognostic factors, preoperative imaging findings are meaningful in univariable but not in multivariable analysis. Furthermore, we propose a model predicting seizure outcomes at 5 years after surgery through the receiver operating characteristic curve and nomogram. The poor outcome group exhibited greater cortical thinning in the ipsilateral precentral and contralateral superior frontal and inferior parietal gyri compared to the good outcome group.

Conclusions: This study showed that nearly 70% of patients with LTLE achieved long-term seizure freedom. The FCD on histopathology independently predicts poor surgical outcomes in patients with LTLE. We also developed a nomogram based on epilepsy duration before surgery and histopathology. If these findings can be confirmed prospectively, they can help select optimal candidates and identify the suitable timing for surgery among patients with LTLE.

Funding: None
Surgery