Magnetic Resonance-Guided Laser Interstitial Thermal Therapy for Brain Metastases Trial

The LITT procedure was performed using the LS1 laser ablation system and SR1 stereotactic robotic system (Sinovation, Beijing, China). The ablation system was equipped with a 980-nm laser with a maximum of 15 W of power, a core silica fiber optic with a 1.8-mm diameter cooling catheter, and a cooling pump to make saline flow into and out through the catheter. The optic and catheter approaches were planned with the preoperative simulation software (Sinovation, Beijing, China) using the preoperative T1-weighted MRI scan, and passing through important cerebral vascular and functional zones was avoided。. The catheter was implanted by neurosurgeons under stereotactic guidance, and a laser probe was inserted through the catheter. After LITT, a T1-weighted intraoperative MRI scan was performed to confirm the effect of ablation. The ablation rate was calculated by another neurosurgeon who did not participate in the study.