Chronic epilepsy associated with temporal tumors: long-term surgical outcome

Abstract

The authors undertook a study to review the clinical features and outcome in patients who underwent surgery for intractable chronic epilepsy caused by temporal lobe tumors. The Rush Surgical Epilepsy Database was queried to identify patients with chronic intractable epilepsy who underwent resection of temporal lobe tumors between 1981 and 2005 at Rush University Medical Center. Medical records were reviewed for age of the patient at seizure onset, delay to referral for surgery, seizure frequency and characteristics, preoperative MR imaging results, extent of resection, pathological diagnosis, complications, duration of follow-up period, and seizure improvement. Thirty-eight patients were identified, all with low-grade tumors. Gangliogliomas were the most common (36.8%), followed in descending order by dysembryoplastic neuroepithelial tumors (26.3%) and low-grade diffuse astrocytoma (10.5%). The mean duration between seizure onset and surgery was 15.4 years. Complex partial seizures were the most common presenting symptom. Detailed operative data were available for 28 patients; of these, 89.3% underwent complete resection of the amygdala, and 82.1% underwent partial or complete resection of hippocampus, in addition to lesionectomy. The mean follow-up duration was 7.7 years (range 1.0-23.1 years), with 78.9% of patients having seizure status that improved to Engel Class I, 15.8% to Engel Class II, and 5.3% to Engel Class III. Permanent complications were noted in 2.6% of patients. The authors' examination of the long-term follow-up data in patients with temporal lobe tumors causing chronic intractable epilepsy demonstrated excellent results in seizure improvement after surgery.