Temporal lobe epilepsy with unilateral amygdala enlargement: morphometric MR analysis with clinical and pathological study

J Neuroimaging. 2015 Mar-Apr;25(2):175-183. doi: 10.1111/jon.12106. Epub 2014 Mar 5.

Abstract

Background and purpose: Amygdala enlargement (AE) has been reported as an epileptogenic focus in subtypes of temporal lobe epilepsy (TLE). The purpose of this study was to investigate the clinical, morphological, and pathological characteristics of AE.

Methods: We retrospectively reviewed the clinical data and imaging findings of 23 TLE patients with ipsilateral AE. We performed morphological MR analyses using FreeSurfer and voxel-based morphometry (VBM) in 14 of the 23 patients and in 20 controls whose images were obtained by a 3.0-Tesla MRI. A pathological study was also performed in 2 patients who underwent operations.

Results: All patients became seizure free or shSowed dramatic improvement by medical therapy except for two. They received operations and their pathology revealed that both patients had cortical dysplasia in from the amygdala to the ipsilateral temporal pole. The FreeSurfer analysis showed a significant difference in the amygdala volumes between the affected and nonaffected sides. VBM revealed significant increases of gray matter volumes of the temporal pole on the side of AE in seven of the 14 patients with AE (50%).

Conclusions: Cortical dysplasia may be one of the pathological diagnoses in AE, and in some patients it may extend to the temporal pole.

Keywords: Amygdala enlargement; FreeSurfer; focal cortical dysplasia; temporal pole; voxel-based morphometry.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Amygdala / pathology*
  • Child
  • Epilepsy, Temporal Lobe / pathology*
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted / methods*
  • Imaging, Three-Dimensional / methods*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Temporal Lobe / pathology*
  • Young Adult