Endfolium sclerosis in temporal lobe epilepsy diagnosed preoperatively by 3-tesla magnetic resonance imaging

A 34-year-old man presented with intractable temporal lobe epilepsy. Three-tesla magnetic resonance imaging revealed increased T2 signal intensity and volume loss limited to the CA4 region of the right hippocampus. A right anterior temporal lobectomy and amygdalohippocampectomy were performed. Histological examination of the hippocampus disclosed severe neuron loss limited to the CA4 region, consistent with the preoperative imaging, which is a pattern known as endfolium sclerosis. Close inspection of the internal hippocampal anatomy with high-field MR imaging is useful in patients with temporal lobe epilepsy, because endfolium sclerosis may be associated with less chance of seizure freedom after temporal lobectomy.