Introduction: MRI guided laser interstitial thermal therapy (LITT) is one of the latest treatment modalities added to the neurosurgical armamentarium. Two LITT systems are in commercial circulation: the Visualase® Thermal Therapy System (Medtronic, Louisville, CO) and the NeuroBlate® System (Monteris Medical Corporation, Plymouth, MN, USA). At the University of Florida, we have adopted a process to deliver LITT using the Neuroblate system with frame-based stereotaxis and local anesthesia.
Methods: A high-resolution MRI is obtained. The scan is mapped onto an orthogonal coordinate system for stereotactic targeting. A patient specific 3D-printed mask with an incorporated trajectory is created. The processed CT scan is fused to a Gadolinium-enhanced, T1 weighted MRI sequence. After verifying image fusion, the affine transform used to map the MR scan onto the stereotactic CT scan is applied to transform the entry and target points of the defined preplan. Positioning on the MRI table is achieved using vacuum cushions for the body and head to immobilize the patient for laser ablation. Custom molded thermoplastic masks are used to secure the head with straps. We then proceed with delivery of LITT.
Results: A total of eleven consecutive patients were treated with LITT at the University of Florida, none of which were placed on general anesthesia. Ten patients received LITT following tumor progression after prior surgical resection. Median operative time was 31.5 minutes (SD 11) and median time of laser delivery was 79 minutes (SD 27). Three patients required light sedation with monitored anesthesia care. The median length of stay was one day (SD 0.9).
Conclusions: LITT can be delivered to patients safely and accurately without general anesthesia.
Patient Care: The work process demonstrates a mechanism by which laser interstitial thermal therapy may be used to treat patients without the use of general anesthesia. This will reduce the risk of anesthesia and cost without resultant prolongation of operative time.
Learning Objectives: 1) How LITT can be safely delivered with framed base stereotaxis and local anesthesia
2) How the use of rapid protoyping to create 3D face masks can assist in probe trajectory