A Personalised Radiosurgery Procedure for People With Trigeminal Neuralgia to Improve Pain, Quality of Life and Reduce Complications - a Confidence in Concept Pilot Study (PROMOTION)

Trigeminal neuralgia (TN) is a condition of excruciating facial pain characterized by brief, repeated, electric shock-like pains. Like idiopathic TN, people with multiple sclerosis (MS) related TN (PwMSTN) often suffer from episodic facial pain (often excruciating) that may be related to demyelination of the trigeminal pathways. It is estimated that people with multiple sclerosis (PwMS) are 20 times more likely to present with TN symptoms than non-MS people and a recent review estimated that 4-8% of PwMS have TN. Patients with TN or MS-related TN who no longer respond to treatment often opt for non-invasive gamma knife radiosurgery (GKRS), with variable outcomes. Factors, such as patient characteristics, target treatment location and radiation dosage, could affect the efficacy of pain relief and result in post-surgical morbidity. There is no consensus of the best GKRS target treatment location or the optimal radiation dosage for GKRS treatment among centers, this results in great variability across centers in patient outcomes of pain control and morbidity. This prospective surgical pilot study will recruit PwTN and PwMS-related TN from the National Center for Stereotactic Radiosurgery, Sheffield, to evaluate the impact of a personalized GKRS treatment protocol on safety, efficacy (pain control) and morbidity. The personalized procedure will target the treatment location on trigeminal nerve further away from the brain stem as compared to the current standard treatment location that is closer to the brain stem. The personalized procedure may reduce the radiation dose to the brain stem and then reduce the adverse effects of the treatment. The recruited PwTN and PwMS-related TN will be randomly allocated to either the personalized GKRS treatment protocol group or the standard GKRS treatment protocol group. The efficacy in pain relief and morbidity will be evaluated between the treatment groups at 6 months and 12 months post-surgery.

This study does not have main ethical, legal issues. The GKRS treatment is provided as routine NHS care, and the study will only alter the treatment location for those patients who would normally go through the standardtreatment protocol. Therefor there will be no management issues.

Information collected during this study will be kept confidential. All data collected for this study will be kept safely and securely on secure NHS computer server and paper records at the clinic. All data will be handled strictly according to the University of Leeds privacy notice for research participants