Epilepsy associated with Leukoaraiosis mainly affects temporal lobe: a casual or causal relationship?

OBJECTIVE: To compare anatomo-electro-clinical findings between patients withepilepsy associated with leukoaraiosis only (EAL) and patients with awell-defined vascular lesion, i.e. post-stroke epilepsy (PSE).METHODS: Two hundred eighty-three subjects with epilepsy and cerebrovasculardisease, consecutively seen in our epilepsy centres from January 2000 to March2014, were retrospectively considered. Inclusion criteria were: history of one ormore unprovoked seizures and MRI evidence of one or more vascular lesions.Exclusion criteria were: inadequate neuroimaging data, coexistence of nonvascularlesions, and psychogenic seizures. Subjects were divided in two groups: PSE andEAL, based onclinical and MRI findings. Epileptogenic focus was identifiedaccording to ictal semiology and EEG findings. In PSE group, coherence betweenthe vascular lesion(s) and epileptogenic focus was scored as likely or unlikely.RESULTS: One hundred seventeen subjects were included: 58 had PSE, 59 EAL.Coherence was identified as likely in 38 (95%) and unlikely in 2 (5%). Atunivariate analysis, abnormal EEG and frontal localization were associated with alower EAL probability [odds ratio (OR) 0.36, 95% confidence interval (CI)0.15-0.87, p=0.02 and OR 0.12, 95% CI 0.04-0.37, p<0.001, respectively], whiletemporal localization was associated with a higher EAL probability (OR 4.0, 95%CI 1.8-9.0, p<0.001). Multivariate confirmed these associations.CONCLUSIONS: While in PSE epileptogenic focus is coherent with the vascularlesions, in EAL temporal lobe epilepsy predominates. In EAL, causal relationship between vascular lesions and epilepsy is not straightforward, and the role ofadjunctive factors needs to be elucidated.