Microsurgical Outcomes of Secondary Epilepsy from Hippocampal Lesions: A Report of 56 Cases and Literature Review.

AIM To explore the treatment efficacy of microsurgery for secondary epilepsy from hippocampal lesions. MATERIAL AND METHODS The clinical data, pathological findings, surgical methods and surgical outcomes of 56 patients with secondary epilepsy from hippocampal lesions were retrospectively analyzed. RESULTS Postoperative pathological examinations confirmed that 27 patients had gliomas, 17 patients had vascular malformations and 12 patients had hippocampal sclerosis. Twenty-nine patients underwent selective resection of the lesioned tissue and the surrounding infiltrated tissue, and 26 patients underwent a more generous removal of the anterior temporal lobe, lesioned tissue, infiltrated tissue and medial structures of the temporal lobe. Fifty patients were followed up with an average follow-up duration of 25.5 months. At postoperative one year, the remission rate of epilepsy that achieved Engel grade I was 80.8% (21/26) and 83.3% (20/24) for the selective resection and more generous resection, respectively, indicating that the difference between the two methods was insignificant. CONCLUSION Microsurgery is the first choice for the treatment of secondary epilepsy from hippocampal lesions. Various operative routes and methods can be selected based on the lesion natures. Long-term favorable outcome of seizure control following microsurgery can be achieved in most of the patients.