Abstract 13- 1515-1530
Category: Clinical

At the end of the session,
participants will be able to:

  1. Compare GCL morphometry between HS, no-HS, and control cases.
  2. Compare GCL morphometry between TLE patients that achieve seizure freedom post-operatively to those that continue to experience seizures after surgical resection.
  3. Investigate dentate gyrus gene expression differences between HS and no-HS cases.
Presenter

Dr. Carolyn Twible

As a graduate student at Western University, my research focus is temporal lobe epilepsy (TLE), more specifically, drug-resistant hippocampal sclerosis (HS) and no-hippocampal sclerosis (no-HS) associated TLE. I am interested in investigating morphometry and gene expression within HS and no-HS cohorts, focusing on the dentate gyrus.

Authors

Carolyn Twible1, Qi Zhang1,2

  1. Department of Pathology and Laboratory Medicine, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
  2. Department of Pathology and Laboratory Medicine, London Health Sciences Centre, London, ON, Canada

Target Audience:
Pathologists, Research scientists

CanMEDS:
Scholar

Characterizing the hippocampal dentate gyrus involvement in temporal lobe epilepsy

Abstract

Hippocampal sclerosis (HS) is the most common pathology finding for drug resistant temporal lobe epilepsy (TLE) and is characterized by neuronal loss and gliotic Cornu Ammonis. Nearly 20% of surgical specimens from drug-resistant TLE surgery contain “normal” populations of neurons, termed no-HS, yet still benefit from surgical resection. This observation suggests a neuropathological explanation for the epileptogenic focus in the resected tissue that is not detected through standard diagnostic practices. The goals of this project are to increase the neuropathological understanding of drug resistant TLE, and to elucidate the structural changes of HS and no-HS, focusing on the granule cell layer (GCL). In this study, 21 TLE surgical resection cases were examined, including 14 HS and 7 no-HS cases, to investigate GCL morphometry. Information on histopathological diagnosis and post-operative outcome were collected. The digital image analysis software QuPath was used to perform cell detection analysis on the GCL. Measures including Delaunay mean cell density were analyzed. HS patients show a significant increase in granule cell spacing and decrease in granule cell density within the GCL compared to no-HS patients. Regardless of the histological diagnosis, patients achieved seizure freedom post-operatively demonstrated an increase in granule cell spacing and decrease in granule cell density in comparison to those that did not achieve seizure freedom post-operatively. HS and no-HS diagnosis groups have disease- and post-operative outcome dependent morphometry differences. The post-operative outcome dependent morphometry observed in HS and no-HS patients presents a potential additional method to evaluate post-operative prognosis for TLE surgical-resection patients.