Long-term control and predictors of seizures in intracranial meningioma surgery: a population-based study.

BACKGROUND: The aim of this retrospective study was to investigate the long-term seizure control and antiepileptic drug (AED) prescriptions, as well as identifying predictors of seizure(s) before and after surgery in a population-based cohort of operated intracranial meningioma patients.

METHODS: A total of 113 consecutive adult (> 18 years old) patients with newly diagnosed meningioma operated at the Karolinska University Hospital between 2006 and 2008 were included and followed up until the end of 2015. Data on seizure activity and AED prescriptions were obtained through chart review and telephone interview. Logistic regression and survival analysis were applied to identify risk factors for pre- and postoperative seizures.

RESULTS: A total of 21/113 (18.6%) patients experienced seizures before surgery of which 8/21 (38.1%) went on to become seizure-free after surgery. Thirteen (14%) patients experienced new-onset seizures after surgery. The regression analysis revealed tumor diameter ≥ 3.5 cm as a risk factor for preoperative seizures (OR 3.83, 95% CI 1.14-12.87). Presence of headache (OR 0.19, 95% CI 0.05-0.76) and skull base tumor location (OR 0.14, 95% CI 0.04-0.44) decreased the risk of preoperative seizures. Postoperative seizures were associated with tumor diameter ≥ 3.5 cm (OR 2.65, 95% CI 1.06-6.62) and history of preoperative seizures (OR 3.50, 95% CI 1.55-7.90).

CONCLUSION: Seizures are common before and after intracranial meningioma surgery. Approximately one third of patients with preoperative seizures become seizure-free on long-term follow-up after surgery, while 14% experienced new-onset seizures after surgery. Larger tumor size, absence of headache, and non-skull base location were associated with preoperative seizures, while tumor size and preoperative seizures were associated with postoperative seizures.