Author(s): Chawira A.; Keller S.; Weber B.
Source: British Journal of Neurosurgery; 2018; vol. 32 (no. 1); p. 101
Publication Date: 2018
Publication Type(s): Conference Abstract
Abstract:Objectives: To investigate whether pre-operative insula volumes correlate with post-operative seizure frequency and outcome in patients undergoing amygdalohippocampectomy for refractory mTLE, in order to develop a useful imaging prognostic marker. No studies to the best of our knowledge have previously examined structural changes in the insula in relation to seizure outcomes. Design: A single-centre retrospective correlational study. Subjects: 86 patients with unilateral mTLE who underwent amyg-dalohippocampectomy and 25 healthy controls were selected and underwent MRI scanning. Methods: Volumetric insula measurements were obtained from T1-weighted MRI scans using stereology with point-counting using EasyMeasure software. Results: Ipsilateral and contralateral insula volumes were significantly smaller in patients than controls. Using bivariate correlational analysis, ipsilateral hippocampal volumes were significantly correlated with contralateral insula volume (p=0.013) with a trend towards the ipsilateral insula (0.060). No relationship was found between insula volume and seizure frequency (ipsilateral p=0.540, contralateral p=0.500) or post-operative outcome (ILAE 1 vs ILAE 2-5: ipsilateral p = 0.783, contralateral p = 0.530). No statistical significance was observed between insula volume and seizure type, sex, or febrile seizures. Conclusions: There is structural atrophy of the insula in patients with mTLE. However, this atrophy is evidently not related to the clinical manifestations of the disorder, including post-surgical outcome.