Introduction: For patients with intracranial cavernous malformations presenting with seizures, various factors can affect postoperative seizure control. We sought to examine long-term seizure outcomes and identify specific prognostic factors that affect seizure freedom following cavernoma resection.
Methods: We performed a retrospective study of patients who underwent resection of supratentorial cavernomas at our institution between 1992 and 2010. The following factors were investigated: age, gender, seizure type and duration, presence of generalized tonic-clonic seizures, cavernoma size, location, multiplicity, and extent of resection. Seizure outcome was scored using the Engel classification.
Results: We identified 56 patients who met inclusion criteria. Mean length of follow-up was 87.9 months. At most recent follow-up 46 patients (82%) were free from impairing seizures (Engel Class 1). Ten patients (18%) had persistent seizures and were classified Engel Class 2-4. 48 out of 56 patients (86%) had longer than 24 months follow-up. Univariate analysis showed that only multiple cavernomas were associated with worse post-operative seizure outcome (p = 0.006). Multivariate analysis showed that multiple cavernomas remained a significant predictor for development of worse seizure outcome when controlling for preoperative duration and frequency of seizures, presence of generalized tonic-clonic seizures, and size (odds ratio, 0.05; 95% confidence interval, [5.5e-3, 0.47]). Specifically there was a 95% lower probability for Engel Class 1 outcome with multiple cavernomas, corresponding to a 19.6 greater odds of worse (Engel Class 2-4) seizure outcome.
Conclusions: The presence of multiple cavernomas is a predictor of poorer postoperative seizure control following cavernoma resection.
Patient Care: Postoperative outcome in those with cavernomas should be a topic for further multi center prospective studies involving larger number of patients. In addition to prior studies looking at ideal operation time, extended resection and other predictors of favorable neurologic or seizure outcome, neurosurgeons should be aware of presence of multiple cavernous and poorer postoperative seizure control when managing the patient.
Learning Objectives: Poorer postoperative seizure control is seen with multiple cavernomas