Small temporal pole encephaloceles in children with presumed nonlesional temporal lobe epilepsy

Abstract

Objective: Temporal lobe epilepsy (TLE) is the one of most common form of focal epilepsy. Children with intractable TLE epilepsy undergo presurgical evaluations for resective treatment. The cases are considered “nonlesional’’ if brain magnetic resonance imaging (MRI) shows no structural abnormality and they sometimes encounter invasive procedures. We describe two patients, initially thought to have “lesion negative” refractory TLE, in whom the recognition of a small anterior temporal encephalocele by close inspection of imaging altered the follow up strategy. Case Presentation: Case 1: 12-year-old girl, focal seizures began at age 10 years, manifesting as no reduced awareness, contractions in the corner of the mouth, and head version. At the time of assessment the patient was having multiple daily attacks. Two antiepileptic drugs in various doses and combinations had failed to control seizures. Early childhood development and schooling were unremarkable. Febrile seizures had not occurred. Video–electroencephalography (EEG) monitoring captured ten typical seizures, all originating from the right temporal region. Prior imaging was reported normal. The current brain MRI has showed small right anterior temporal tip encephalocele through a congenital defect in the sphenoidal bone. She is now a epilepsy surgery candidate. Case 1: 15-year-old girl, discognitive seizures began at age 6 years characterized by a rising abdominal sensation and impaired consciousness. Seizures continued weekly with no evolving to bilateral convulsive seizures, despite trials of two anticonvulsants in various doses and combinations. Febrile seizures had not occurred. Routine EEG showed interictal epileptiform activity in left temporal region. Prior imaging was reported normal. The current brain MRI has showed bilateral temporal tip encephalocele greater on the left. She will be hospitalized for phase I epilepsy surgery evaluations. Conclusion: We would like to present this cases to emphasize the discovery of an occult lesion such as an encephalocele markedly alters treatment opinions in children.