Sala-Padro Jacint, Miró Júlia, Rodriguez-Fornells Antoni, Quintana Manuel, Vidal Noemí, Plans Gerard, Santurino Mila, Falip Mercè, Camara Estela
Epilepsy Unit, Hospital de Bellvitge, Spain; Cognition and Brain Plasticity Group, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, 08097, Spain.
Cognition and Brain Plasticity Group, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, 08097, Spain; Department of Cognition, Development and Educational Science, Campus Bellvitge, University of Barcelona, L'Hospitalet de Llobregat, Barcelona, 08097, Spain; Catalan Institution for Research and Advanced Studies, ICREA, Barcelona, Spain.
Seizure. 2020 Jan 26;76:84-88. doi: 10.1016/j.seizure.2020.01.006.
Our aim was to study the microstructural architecture of the contralateral hippocampus to the affected side in patients with temporal lobe epilepsy with hippocampal sclerosis (TLE-HS) and its relation with surgical outcome.
We included 33 consecutive patients evaluated in our epilepsy surgery program during a five-year period. They underwent a presurgical MRI with volumetric T1 and diffusion weighted sequences. 22 patients with TLE-HS (13 women, 12 right TLE-HS) were finally selected. Median follow-up after surgery was 6.25 years (4.5-8.83 years). We segmented the hippocampal subfields of the contralateral hippocampus using FreeSurfer and calculated the fractional anisotropy (FA) and the mean diffusivity (MD) of each subfield. We also scanned 18 healthy age-matched controls.
After surgery, 50 % of the patients (n = 11) remained seizure-free (SF) following surgery. Comparing non-SF to SF patients, the MD showed increased values of the CA1 (p = 0.035), the molecular layer (p = 0.010) and the dentate gyrus (p = 0.041) in the healthy hippocampus. Using a cut-off point for a survival analysis, we found that patients with lower values of MD of the molecular layer and the CA1 remained SF during long-term post-operative follow-up (p < 0.0001).
The contralateral hippocampal internal microstructure may have be implicated in post-surgery seizure freedom in patients with TLE-HS.
