Enlarged perivascular space in the temporal lobe as a prognostic marker in temporal lobe epilepsy with hippocampal sclerosis

Abstract

Objective: This study was undertaken to investigate the regional burden of enlarged perivascular spaces (EPVSs) in patients with temporal lobe epilepsy with hippocampal sclerosis (TLE-HS) and explore its prognostic relevance. Methods: In this retrospective observational study, EPVSs in the temporal lobe (T-EPVS), centrum semiovale (CS-EPVS), basal ganglia (BG-EPVS), midbrain, and hippocampus were visually rated in 68 treatment-naïve patients with TLE-HS. Regional EPVS burden was dichotomized into high and low degrees (cutoff: >10 for BG-EPVS/T-EPVS; >20 for CS-EPVS). Cox proportional hazards models were used to determine the potential predictors of seizure freedom (SF; no seizure for >1 year) and delayed SF (SF achieved >6 months after initiating antiseizure medication [ASM]). Multivariate logistic regression using stepwise variable selection based on the Akaike information criterion was performed to investigate whether EPVS burden was associated with medical refractoriness (never achieving SF). Results: Of the 68 patients, 20 were classified into the refractory group (29.4%). The high T-EPVS group had an older epilepsy onset (37.3 ± 12.3 vs. 26.5 ± 13.0 years, p =.005), higher pretreatment seizure density (median = 12.0, interquartile range [IQR] = 5.0–20.0 vs. 4.0, IQR = 2.0–10.5, p =.008), and lower focal to bilateral tonic–clonic seizure prevalence (13.3% vs. 73.6%, p