Risk Factors of Preoperative Seizures and Predictors of Late Postoperative Seizures in Patients with Meningioma

Abstract

Objective: Seizures are common among patients with meningiomas and are considered to be a significant cause of morbidity and poor quality of life. We identified factors associated with the onset of preoperative seizures as well as predictors associated with late postoperative seizures.

Methods: Between July 2003 and December 2014, we retrospectively reviewed the medical records of 303 patients who underwent primary resection for supratentorial meningioma at Seoul National University Bundang Hospital. Univariate analysis and multivariate logistic regression analysis were performed to determine the association between seizure occurrence and prolonged seizure outcome after surgery.

Results: Forty-nine (16.2%), out of the 303 patients reviewed, presented with preoperative seizures. The risk factors independently associated with preoperative seizures were absence of preoperative neurologic deficit (HR0.297, p=0.003), parasagittal or parafalcine location (HR2.197, p=0.023), and vasogenic edema (HR4.429, p=0.001). Among these patients, 33 (67.3%) were seizure free during the entire postoperative follow-up period (54.5±33.8 months). Of the 303 patients, we observed late postoperative seizures in 35 (11.6%) patients. The associated risk factors included history of preoperative seizure (HR3.956, p=0.002), bigger tumor size (HR1.041, p=0.002), and continuation of anti-epileptic drugs (HR4.741, p=0.001). We observed that meningiomas with a largest diameter of greater than 45.5mm were 4.2 times more likely to have late postoperative seizures than those with a diameter of less than 45.5mm. (HR4.191, 95% CI 1.9990 – 8.824, p<0.001). Ten patients (28.6%) experienced poor seizure control. The independently associated predictive factors were high grade meningiomas (WHO Grade II or III) (HR 10.663, p=0.035) and history of postoperative adjuvant therapy (HR12.581, p=0.042).

Conclusions: Identifying factors associated with preoperative or late postoperative seizures may help guide treatment strategies, ultimately improving the quality of life for patients with meningiomas.