Predicting outcome of epilepsy after meningioma resection

Surgical excision is the standard treatment for intracranial meningiomas. Epilepsy is a major cause of morbidity in meningioma patients, but postoperative control of epilepsy is not achieved in a substantial fraction of patients. The purpose of this study was to define risk factors for postoperative epilepsy.

Patients treated for histologically confirmed intracranial meningioma at the University Hospital Zurich between 2000 and 2013 were retrospectively analyzed. Demographic, clinical, imaging, and electroencephalographic data were assessed. A binary regression model was applied to identify risk factors for postoperative epilepsy.

Of the 779 patients analyzed, epileptic seizures occurred in 244 (31.3%) patients before surgery and in 204 (26.6%) patients after surgery. Of the 244 patients with preoperative epilepsy, 144 (59.0%) became seizure-free after surgery; of the 535 patients without preoperative seizures, 104 (19.4%) suffered from epilepsy after surgery. Risk factors for postoperative epilepsy were preoperative epilepsy (odds ratio [OR]: 3.46 [95% confidence interval {CI}: 2.32-5.16]), major surgical complications including CNS infections (OR: 5.89 [95% CI: 1.53-22.61]), hydrocephalus (OR: 3.27 [95% CI: 1.35-7.95]), recraniotomy (OR: 2.91 [95% CI: 1.25-6.78]), and symptomatic intracranial hemorrhage (OR: 2.60 [95% CI: 1.17-5.76]) as well as epileptiform EEG potentials (OR: 2.52 [95% CI: 1.36-4.67]), younger age (OR: 1.74 [(95% CI: 1.18-2.58]), and tumor progression (OR: 1.92 [95% CI: 1.16-3.18]). Postoperative improvement or recovery from preoperative neurologic deficits was associated with improved seizure control (OR: 0.46 [95% CI: 0.25-0.85], P = .013).

We suggest prospective validation of a score ("STAMPE2") based on clinical findings, EEG, and brain-imaging measures to estimate postoperative seizure risk and guide anticonvulsant treatment in meningioma patients.