Efficacy and safety of ct-guided radiofrequency ablation via the stylomastoid foramen for primary hemifacial spasm: A retrospective study

Background This study aims to investigate the efficacy and safety of CT-guided radiofrequency ablation (RFA) targeting the facial nerve via the stylomastoid foramen in treating primary hemifacial spasm (HFS), with a focus on short-term outcomes. Patients and methods This study retrospectively included patients diagnosed with primary HFS who underwent partial radiofrequency ablation of the facial nerve at the Pain Department of the First Hospital of Jiaxing from August 2018 to August 2023. All patients successfully underwent percutaneous puncture under CT guidance and received continuous standard radiofrequency treatment, characterized by a stepwise temperature increase from low to high. We collected basic preoperative data and conducted regular follow-ups with the patients postoperatively. The study recorded and analyzed the varying House-Brackmann (HB) grades of facial paralysis following surgery, the time to recurrence, intraoperative and postoperative complications, as well as the Self-Rating Anxiety Scale (SAS) scores and Self-Rating Depression Scale (SDS) scores of the patients before and after treatment. Results A total of 195 patients were included, with a median follow-up of 15 months (range: 1–58 months). Of the 195 patients, 182 (93.3%) had a follow-up duration of at least 3 months, 158 (81.0%) had at least 6 months, and 86 (44.1%) had at least 12 months of follow-up. Patients who did not experience recurrence during the study period were censored at the time of their last follow-up contact. The follow-up completion rates at predefined time points are summarized in Table 5. Kaplan-Meier analysis estimated the cumulative recurrence-free survival rates as 90.3% at 3 months, 79.3% at 6 months, and 52.7% at 12 months. The median recurrence-free survival time was 13 months (95% CI: 12–18 months). The overall crude recurrence rate during the entire follow-up period was 52.8% (103/195). Postoperative facial nerve function was assessed using the House-Brackmann (HB) grading system. Among the 195 patients, 49 (25.1%) maintained normal facial function (HB Grade I), 76 (39.0%) developed mild facial weakness (HB Grade II), and 70 (35.9%) developed moderate facial weakness (HB Grade III). No patient experienced severe (Grade IV or higher) paralysis. Most cases of facial weakness showed gradual improvement during the 3-month follow-up period; however, the relatively short evaluation period limits the assessment of long-term facial nerve recovery. All 195 patients had scheduled House-Brackmann assessments at predefined postoperative time points (Table 4). Conclusion In this retrospective study of carefully selected patients who declined botulinum toxin injections and microvascular decompression, CT-guided radiofrequency ablation of the facial nerve via the stylomastoid foramen was associated with immediate symptom improvement but showed substantial recurrence during follow-up. These preliminary observational findings suggest that this minimally invasive approach may serve as an alternative option for selected patients, but its efficacy relative to established treatments remains to be determined. Trial registration Chinese Clinical Trial Registry, ChiCTR2500103743, registered on June 5, 2025.