Cyberknife radiosurgery for hemifacial spasm

Background: Surgical management of hemifacial spasm (HFS) may be contraindicated in medically unfit patients or declined because of the potential risks associated with surgery. Therefore, minimally invasive and non-invasive alternatives merit investigation. This preliminary study aims to evaluate the safety, efficacy, and optimal technical parameters of CyberKnife radiosurgery for HFS. Methods: We present the first observational study using CyberKnife for HFS in non-tumor HFS cases, including idiopathic, vascular, post-COVID, post-palsy, and co-existing trigeminal neuralgia (TN). An extensive literature review was conducted. Results: CyberKnife radiosurgery resulted in significant reductions in the severity, frequency, and duration of HFSs, increased voluntary suppressibility, with clinical improvement typically observed within a short time frame and without treatment-related complications. Trigger-induced spasms were markedly reduced, while continuous spasms showed the greatest responsiveness to treatment. A parallel improvement in HFS and TN was noted. This literature review has enabled us to identify and discuss optimal radiation doses and targeting strategies for this novel technique in treating HFS, providing clearer radiosurgical parameters for future studies. Conclusion: The results indicate efficacy and safety with the recommended radiosurgical parameters for treating various types of HFS through radiosurgery. We encourage larger studies to establish robust, comprehensive evidence, particularly in patients with coexisting TN.