Risk factors for preoperative and late postoperative seizures in primary supratentorial meningiomas

We performed a retrospective study to identify factors associated with preoperative and late postoperative seizures in primary supratentorial meningiomas.

Between July 2003 and December 2014, we extracted 303 consecutive patients who underwent primary resection for supratentorial meningiomas at a single institution. Univariate analysis and multivariate logistic regression analysis were performed to determine the associations of seizure occurrence and outcome.

Forty-nine (16.2%) of the total 303 patients presented with preoperative seizures. The risk factors independently associated with preoperative seizures were vasogenic edema (OR 4.44, p = 0.001), parasagittal or parafalcine location (OR 2.20, p = 0.020), and absence of neurologic deficit (OR 0.30, p = 0.003). Among these patients, 33 (67.3%) were seizure free postoperatively (Engel Class I). Of the 303 patients, we observed late postoperative seizures in 35 (11.6%) patients. The associated risk factors included history of preoperative seizure (OR 3.96, p = 0.002), bigger tumor size (OR 1.04, p = 0.002), and continuation of anti-epileptic drugs (OR 4.74, p = 0.001). We analyzed that meningiomas with a largest diameter of greater than 45.5 mm were 4.2 times more likely to have late postoperative seizures than those with less diameter (HR 4.20, p < 0.001). Ten (28.6%) of the 35 patients with late postoperative seizures experienced poor seizure control. The independently associated predictive factors were high grade meningiomas (WHO Grade II or III) (OR 10.66, p = 0.030) and history of postoperative adjuvant therapy (OR 12.58, p = 0.040).

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