Supplementary Material for: Stereotactic Focused Ultrasound Mesencephalotomy for the Treatment of Head and Neck Cancer Pain

Introduction. Historically, stereotactic mesencephalotomy was developed as a ‘supraspinal’ cordotomy for cancer and neuropathic pain. Early experiences relieved pain, but the procedure was never widely adopted because of the associated morbidity with midbrain lesioning. Contemporary image-guided lesioning could make this a feasible procedure for cancer patients suffering with pain.
Methods. A single-center, nonrandomized, early phase trial was designed to treat patients with severe, refractory pain from head and neck cancer with unilateral MRI-guided focused ultrasound mesencephalotomy. Safety was the primary outcome, but measures of efficacy were assessed with pain intensity and more functional components of pain.
Results. A discrete midbrain lesion was created for the five patients. Two had profound pain relief, one was partial, and two others were very brief. One patient was transiently obtunded and other procedural morbidities were mild: numbness (3), oculomotor disturbance (1), and agitation (1). Electroencephalography, somatosensory evoked potentials, and quantitative sensory testing were obtained when possible.
Conclusion. Stereotactic focused ultrasound mesencephalotomy is a modern, image-guided, lesioning technique that may be effective for cancer pain.