Magnetic Resonance-Guided Laser Interstitial Thermal Therapy Using Dual-Wavelength Dual-Output Laser Within Two Probe Trajectories for Treatment of Drug-Resistant Epilepsy

Abstract

Objective: Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a novel tool and a minimally invasive treatment to drug-resistant epilepsy (DRE). The focus of this research was to evaluate the effectiveness and safety of the newly developed dual-wavelength dual-output MRgLITT system LaserRO within two probe trajectories in treating DRE patients.

Methods: This is a retrospective analysis conducted at a single center, examining patients with DRE who received treatment with the LaserRO MRgLITT system. The system utilizes a sophisticated laser technology that can be configured as conventional single output for single wavelength or innovative dual outputs for dual wavelengths. The study involved a comprehensive review of patient information, encompassing demographics, seizure history, details related to the surgical parameters, and the subsequent clinical results. Primary outcome was post-operation seizure outcome defined as Engel Scale Class at the end of follow-up time.

Results: This study included a total of eight DRE patients received MRgLITT surgery between August 2022 and October 2023. Out of these, there were four mesial temporal lobe epilepsy (MTLE), three focal cortical dysplasia (FCD), and one cavernous malformation (CM) patients. Within the two probe trajectories, seven patients had single wavelength (980 or 1064 nm) laser treatment and one patient had dual-wavelength (980 and 1064 nm) laser treatment. The median age of the patients was 27 (22-31) years, with a median follow-up period of 9.7 (8.4-12.1) months. The mean BMI was recorded at 20.24 ± 2.95 kg/m², and epilepsy history was 13 ± 6 years. The median intraoperative blood loss was 5 (5-9) mL, operation time was 231 (169-254) minutes, and length of stay (LOS) was 3 (3-5) days. The mean ablation volume ratio was 96.52% ± 3.67%. In terms of outcomes, over a median follow-up time of 9.7 (range 8.4-12.1) months, there were two patients got Engel I, five patients got seizure-free, and one patient decreased 75% seizure. Importantly, no serious complications following the procedures occurred.

Conclusions: The preliminary results indicate that the MRgLITT procedure, which operates dual-output laser with single or dual wavelengths (980/1064 nm) within the two trajectories, is both effective and safe as a minimally invasive approach for different types of DRE patients.

Keywords: Epilepsy; intraoperative MRI; laser ablation; laser interstitial thermal therapy; seizure.