Abstracts

RATIONALE: Surgical therapy has become a standard consideration in patients with medically intractable localization-related epilepsy. We describe our recent experience with epilepsy surgery at the University of Iowa.
METHODS: We retrospectively reviewed our epilepsy surgery database, and included patients with operations performed by a single neurosurgeon (M.H.) between 1993-2001. All patients received a standardized preoperative investigation, including a seizure protocol magnetic resonance image (MRI) of the brain, electroencephalography (EEG) and inpatient prolonged video-EEG monitoring, positron emission tomography (PET) scanning, and neuropsychological and sodium amytal (Wada) testing. Selected patients also received ictal single photon emission computed tomography (SPECT). Patients subsequently received either anterior temporal lobectomy (ATL), extratemporal resection (ETR), or multiple subpial transections (MST) after localization of the surgical epileptic focus and determination of functional anatomy. A modified-Engel outcome classification was utilized (1=seizure-free or auras only, 2=greater than 90% improvement, 3=greater than 75% improvement, 4=no significant improvement or worse). We attempted to contact all patients by telephone who had greater than one year follow-up.
RESULTS: 93 patients underwent epilepsy surgery. Follow-up of over one year was available in 84 patients. 72 (86%) completed a telephone survey regarding seizure outcome. The long-term seizure outcomes for 61 ATL patients (mean follow-up 3.6 years) were: Class 1=forty-seven (77%); Class 2=seven (11%); Class 3=four (7%); and Class 4=three (5%). No significant difference in excellent outcome was observed between side of resection (left=33, right=28), by underlying pathological substrate, or whether patients received Phase 1 (n=42) or Phase 2 (n=19) evaluation. Forty-two (90%) of Class 1 outcome patients following ATL rated their overall quality of life as [dsquote]significantly better[dsquote] or [dsquote]better.[dsquote] The seizure outcomes for patients with ETR (n = 10) were: Class 1=two (20%); Class 2=two (20%); Class 3=one (10%); and Class 4=five (50%). One patient received multiple subpial transections (MST) and had a Class 4 outcome.
CONCLUSIONS: Our surgical outcome was comparable to recently published large series, reaffirming the value of epilepsy surgery for carefully selected patients with medically intractable localization-related epilepsy.
[Supported by: The Roy A. and Lucille J. Carver College of Medicine]