Epilepsy and Low-Grade Gliomas - Seizure Control After Surgical Resection: A Retrospective Cohort

Introduction: Seizures occur in 60-75% of patients with low-grade gliomas (LGGs). 60 – 90% of patients attain seizure freedom after resection. Seizure control varies with histopathology, the extent of resection (EOR), and the type of seizures. There is an inconsistency in the literature regarding the utility of anti-epileptic drugs (AED) after tumor resection. We aimed to determine factors associated with seizure control in patients after LGG resection.

Methods: We conducted a retrospective cohort study using the medical records of all patients who underwent LGG resection at our center from 2019 to 2021. 77 patients fulfilled the selection criteria and were contacted via phone calls to collect information about their seizure control as per Engel Classification. The data was analyzed using SPSSv21.

Results: The mean age was 34.9  11.3 years, and there was male predominance (62; 80.5%). Generalized seizures were the most common type (54; 70%), and Levetiracetam was the most commonly prescribed AED (60; 77.9%). The median duration of pre-operative AED use was 4 (IQR: 1 – 24) months. The frontal lobe was the most common location of tumor (36; 46.8%). Most of the patients had their surgery under general anesthesia (51; 61.4%), while 29 (37.7%) underwent awake craniotomy. Nearly half of the patients had a gross total resection (31; 40.3%), and another 15 (19.5%) had near-total resection. Sixteen patients (20.8%) had their AEDs stopped within the first 6 months post-operatively (at variable intervals), and all of them had Engel Class IA to ID control at the time of follow-up (p = 0.008). The 12 patients with Grade I glioma also had optimum seizure control (p = 0.032).

Conclusion : Patients with grade I glioma have better seizure control after surgery. Further studies are required with larger samples to establish guidelines on achieving adequate postoperative seizure control in LGG patients.