Neurophysiology-Guided Laser Interstitial Thermal Therapy: A Synergistic Approach For Motor Function Preservation. Technical Note.

ABSTRACT

BACKGROUND: Laser interstitial thermal therapy (LITT) is a minimally invasive ablative technique with specific indications for neuro-oncology, especially in the case of lesions in eloquent areas. Even being performed through a small catheter under stereotactic conditions, the risk of damaging vital structures such as white matter tracts or cortical eloquent areas is not negligible. The mechanism of damage can be related to catheter insertion or to excessive laser ablation. An accurate preoperative workup, aimed at locating the eloquent structures, can be combined with a real-time intraoperative neurophysiologic monitoring to reduce surgical morbidity while maximizing the efficacy of LITT. METHODS: We developed a synergistic approach for neurophysiology-guided LITT based on state-of-the-art technologies, namely, magnetoencephalography, diffusion tensor imaging, and intraoperative neurophysiologic monitoring. RESULTS: As a result, we improved the planning phase thanks to a more precise representation of functional structures that allows the simulation of different trajectories and the identification of the most suitable trajectory to treat the lesion while respecting the functional boundaries. Catheter insertion is conducted under continuous neurophysiologic feedback and the ablation phase is modeled on the functional boundaries identified by stimulation, allowing it to be extremely accurate. CONCLUSIONS: An integrated approached guided by neurophysiology is able to reduce the surgical morbidity even in a relatively accurate technique such as LITT. To the best of our knowledge, this represents the first report on this synergistic approach which could really impact the treatment of tumors in eloquent areas. Future studies are needed in the effort to implement this approach in functional or epilepsy neurosurgery as well.