LOCL-09 SHORT-TERM SEIZURE OUTCOMES IN PATIENTS WITH TREATED WITH LASER INTERSTITIAL THERMAL THERAPY

Laser interstitial thermal therapy (LITT) is a minimally invasive treatment modality for intracranial tumor and radiation necrosis (RN). A transient increase in edema following LITT typically resolves within three months post-procedure. We sought to characterize the short-term seizure outcomes during this period for patients undergoing LITT for tumor or RN. A retrospective analysis of 86 consecutive patients treated with LITT from 2015-2019 at a single institution was conducted. Data on baseline demographics, treatment details, and clinical course were collected. Thirty-one (36%) had a seizure within one year following LITT, 19 (22%) of which occurred within the first 90 days post-LITT (71% of all seizures). Forty-three (50%) patients had documented pre-LITT seizures, with 27 (63% of all seizures) of those occurring within 90 days pre-LITT. Between patients with and without post-LITT seizures within the first 90 days, there were no significant differences in gender, age, pre-LITT KPS, pre-LITT volume, pre-LITT resection, pre-LITT stereotactic radiotherapy, pre-LITT chemo- or immuno-therapy, use of AEDs or steroids before or after LITT, location, or pathology at the time of treatment. Patients with seizures in the first 90 days post-treatment were significantly more likely to have received pre-LITT whole brain radiotherapy (WBRT) (32% vs. 9%, p=0.02). Of the 18 patients with pre-LITT seizures within 90 days, 9 (50%) were entirely seizure free in the 90-day post-LITT period. In summary, seizure is a known complication of LITT for intracranial lesions, with the majority occurring in the first 90 days post-procedure. WBRT was significantly associated with 90-day post-LITT seizure, which may represent a diminished neurologic reserve in these patients. These findings may help guide clinicians in determining patients appropriate for LITT and those who may require closer monitoring and longer AED tapers in the short-term period following ablation.