Parahippocampal epilepsy with subtle dysplasia: A cause of "imaging negative" partial epilepsy.

Abstract

PURPOSE: Lesion-negative refractory partial epilepsy is a major challenge in the assessment of patients for potential surgery. Finding a potential epileptogenic lesion simplifies assessment and is associated with good outcome. Here we describe imaging features of subtle parahippocampal dysplasia in five cases that were initially assessed as having imaging-negative frontal or temporal lobe epilepsy. METHODS: We analyzed the clinical and imaging features of five patients with seizures from the parahippocampal region. RESULTS: Five patients had subtle but distinctive magnetic resonance imaging (MRI) abnormalities in the parahippocampal gyrus. This was a unilateral signal abnormality in the para..