RELATION BETWEEN ILAE HIPPOCAMPAL SCLEROSIS CLASSIFICATION AND CLINICAL FINDINGS IN TEMPORAL LOBE EPILEPSY

Hippocampal sclerosis (HS) is the most common neuropathological finding in patients undergoing surgery for drug-resistant temporal lobe epilepsy. Approximately 60-90% of patients operated for HS live without a seizure. In 2013, the International League Against Epilepsy (ILAE) reported a new classification based on specific cell losses in Hippocampal Sclerosis. We aimed to investigate the relationship between clinical features and prognosis of the HS cases and ILAE histopathology classification. A hundred patients with refractory epilepsy who were operated with the diagnosis of the Mesial Temporal Lobe Epilepsy were included in the study. Socio-demographic characteristics, clinical and family histories, post-operative ILAE and Engel epilepsy scores and diagnostic tests were recorded. At the same time, all of the pathological specimens were classified according to the new semi-quantitative ILAE classification. A significant statistical relationship was investigated between clinical data and HS-ILAE groups. There were 36 male 64 female patients. The mean follow-up period was 6.5 years. 75% of the cases were HS-ILAE type 1, 19% HS-ILAE type 2, 6% were unidentifiable. FCD3A was detected in 3 patients. The HS-ILAE Type 2 ratio was high on the right-sided cases. In addition, HS-ILAE Type 1 ratio was high in patients with early seizure onset and long duration of epilepsy. There was no significant relationship between long-term ILAE and Engel epilepsy outcome scores and HS-ILAE types. Resection of mesiotemporal structures in hippocampal sclerosis provides seizure control in at least two-thirds of cases. Histopathological findings may help us understand the epileptogenicity-prognosis of HS. The relationship between ILAE histopathology classification and clinical factors will become more obvious in the future. According to our study, there was a relationship between onset age of epilepsy, epilepsy duration, lesion side and HS-ILAE types. The reinforcement of these relationships with larger series will benefit clinicians.