Intraoperative CT-Guided Neuronavigation for Radiofrequency Rhizotomy in Trigeminal Neuralgia: Optimizing Cannulation Trajectories for Individual Anatomy

Abstract Objectives Fluoroscopy-guided radiofrequency rhizotomy for trigeminal neuralgia relies on biplanar fluoroscopic imaging and surface landmarks. However, anatomical variations and imaging limitations often necessitate multiple attempts, leading to patient discomfort and increased procedural risks. This study evaluated the procedural outcomes of radiofrequency rhizotomy using preplanned trajectories and intraoperative computed tomography with neuronavigation. Design Retrospective study. Setting Single-center study conducted in a neurosurgical department. Subjects Forty-six patients with trigeminal neuralgia who underwent radiofrequency rhizotomy between September 2019 and December 2024 were recruited in this study. Methods Cannulation was performed using navigation-guided trajectories, with intraoperative computed tomography employed to adjust the trajectory if initial attempts failed. Success rates and the distances between the landmark-based and neuronavigation-guided entry points were measured. Results Among the 46 procedures, the entry points were adjusted from the landmark-based entry points in 22 patients (47.8%) to achieve successful foramen ovale cannulation. Adjustments involved inferolateral displacement in 17 cases and inferomedial displacement in five cases. The mean lateral displacement was 3.75 ± 5.40 mm, and the mean inferior displacement was 14.65 ± 6.91 mm. Foramen ovale cannulation was successfully achieved in all the patients without complications. Conclusions Intraoperative computed tomography and navigation-guided radiofrequency rhizotomy are safe and effective techniques for treating trigeminal neuralgia. The conventional entry point designated by surface landmarks was not optimal in 47.8% cases, who required an inferior shift to accommodate anatomical variations.