Abstracts

Rationale: Seizures commonly occur in patients with brain tumors. They are the presenting symptom of a neoplasm in 20-40% of patients diagnosed with a brain tumor, and an additional 20-45% of patients will eventually experience a seizure at a later time [1]. They are often life changing events, posing serious problems, and might even cause greater disability than the underlying tumor. The risk of developing seizures is related to several factors, including the location of the tumor, grade and speed of growth of the tumor, number of brain tumor lesions, and patient age. Location of the tumor may be the most important factor influencing the seizure risk, and low grade, slowly growing primary tumors have the highest association with seizures. Meningiomas in the parasagittal region along the falx cerebri and the middle third of the sagittal sinus have been reported to have a high (74%) seizure prevalence rate [2]. A patient found to have a brain tumor is often started on an antiseizure medication after a single seizure. However, there is no guideline stating when to stop antiseizure medication in patients with a history of seizure prior to meningioma resection. The aim of this study is to assess risk of recurrence after surgery in patient with a history of seizures prior to meningioma resection. Methods: This is a retrospective, data extraction study. IRB was approved at Lahey Hospital & Medical Center on March 23rd, 2018. 114 patients were found from EPIC by searching 'seizure' and/or 'meningioma' from 6/2017 to 6/2018. Out of 114 patients, 107 patients were excluded because they either did not develop seizures pre-operatively, or did not undergo meningioma resection, or both. We analyzed information of seven patients including but not limited to: imaging findings, EEG results, clinical findings, reported side effects and adherence to medication, preoperative seizure frequency, type and management, operative findings and treatment, pathological diagnosis, and postoperative seizure frequency, type and management at 3,6, 12, 24 months, and 36 months. Results: All seven patients who presented with seizures, were started on levetiracetam prior to meningioma resection. Four patients (57%) had seizure recurrences within 3 months to 36 months post-operatively. Three out of four patients (75%) were not on antiseizure medication at the time of seizure recurrence. Antiseizure medication was stopped from 6 to 12 months after resection in this group. Three patients who did not develop seizure recurrence followed from 12 to 36 months remained on antiseizure medication.  Conclusions: Those who presented with preoperative seizures were significantly more likely to develop epilepsy after craniotomy and excision of meningioma when antiseizure medication was discontinued. It might be preferable to continue antiseizure medications for a longer period of time in this patient population.  Funding: No funding