Benign mesial temporal lobe epilepsy.

Benign mesial temporal lobe epilepsy (bMTLE), which is defined as at least 24 months of seizure freedom with or without antiepileptic medication, has probably been under-recognized because of a literature bias toward refractory epilepsy cases. Seizure onset in bMTLE tends to be in adolescence or adulthood, and patients frequently have a family history of febrile seizures and epilepsy. Long-term seizure freedom is observed with or without antiepileptic medication. On brain MRI, nearly 40% of patients with long-standing bMTLE show evidence of hippocampal sclerosis, a feature usually associated with refractory temporal lobe epilepsy. Prospective studies are needed to determine the features that allow prediction of a benign course, and to clarify the significance of hippocampal MRI changes.