Medial temporal lobe epilepsy associated with misplacement of a ventricular shunting catheter

We report the case of a 35-year-old woman who developed right medial temporal lobe epilepsy associated with misplacement of a ventricular shunting catheter in the apex of the right temporal lobe. At 8 years of age, the patient had undergone total removal of a cerebellar astrocytoma and placement of a Torkildsen's ventriculo-cisternal shunt for obstructive hydrocephalus. Although the postoperative course was uneventful, she developed medically intractable psychomotor seizures with secondary generalization at 24 years of age. CT revealed that the tip of the shunting catheter was misplaced in the apex of the right temporal lobe, through the posterior and inferior horn of the right lateral ventricle. Intraoperative electrocorticography revealed frequent paroxysmal activity in the hippocampus, so hippocampectomy as well as removal of the shunting catheter was performed. Postoperatively, the patient became seizure-free, and pathological examination revealed hippocampal sclerosis.