Abstracts

Rationale: Magnetic resonance (MR)-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive technique that can create lesions in the mesial temporal structures with little damage to surrounding tissues without craniotomy. Early data suggest that MRgLITT is associated with favorable surgical outcomes and cognitive function in patients with mesial temporal lobe epilepsy. The aim of the study is to determine the effectiveness MRgLITT in treating patients with drug-resistant mesial temporal lobe epilepsy (mTLE) in a single epilepsy center. Methods: We retrospectively reviewed medical records and determined surgical outcomes in 15 patients with drug-resistant mTLE who underwent MRgLITT from January 2014 to February 2016 with intra-operative CT guidance at the University of Chicago Medical Center. Nine patients had mesial temporal sclerosis (MTS) and six patients had negative brain MRI studies. The mean age of patients at the time of surgery was 40.3 13.4 years, and the mean duration of post-operative follow up was 13.7 6.9 months. Results: Following the MRgLITT, seizure freedom was achieved in 8 (53%) of 15 patients and reduction of seizure frequency by more than 50% was achieved in 12 (88%) of 15 patients. Seven (78%) of 9 patients with MTS achieved seizure freedom, whereas 1 (17%) of 6 patients without MTS achieved seizure freedom. MRgLITT was well tolerated without significant post-operative complications except in one patient who developed a homonymous hemianopsia. We subsequently used diffusion tensor imaging to define the visual pathways during surgical planning for preventing this complication Conclusions: MRgLITT is a safe treatment in patients with mTLE, and has a high probability of achieving seizure freedom in patients with MTS. However, it is less likely to result in seizure freedom in those without MTS. Given the limited case numbers, future multicenter prospective studies are warranted to validate the findings in this study. Funding: None