Preoperative imaging evaluation of primary trigeminal neuralgia using 3D TOF-MRA and 3D FIESTA-c: A retrospective study of 412 cases

OBJECTIVE: To evaluate the clinical value of three-dimensional time-of-flight magnetic resonance angiography (3D TOF-MRA), three-dimensional fast imaging employing steady-state acquisition with phase cycling (3D FIESTA-c), and their combination for preoperative assessment of responsible vessels in primary trigeminal neuralgia (PTN) before microvascular decompression (MVD). METHODS: We retrospectively reviewed 412 patients with PTN confirmed by MVD who underwent preoperative 3D TOF-MRA and 3D FIESTA-c. Intraoperative findings served as the reference standard. Diagnostic performance was assessed using 2 criteria: binary identification of the presence or absence of a responsible vessel and complete concordance of vessel type. Agreement with surgical findings was evaluated using Cohen's kappa. Subgroup analyses were performed according to responsible vessel type. RESULTS: Responsible vessels were identified intraoperatively in 407 of 412 patients (98.79%), whereas no responsible vessel was found in 5 patients (1.21%). The superior cerebellar artery (SCA) was the most common responsible vessel (250/412, 60.68%), followed by involvement of the SCA and petrosal vein (54/412, 13.11%). Under binary criteria, the accuracy of 3D TOF-MRA, 3D FIESTA-c, and the combined approach was 90.53%, 91.99%, and 96.36%, respectively, with a significant overall difference (Cochran's Q = 23.400, P < 0.001). Under complete concordance criteria, the corresponding matching rates were 74.27%, 82.77%, and 87.86%, respectively, with kappa values of 0.531, 0.702, and 0.786 (Cochran's Q = 64.892, P < 0.001). Pairwise comparisons showed that the combined approach outperformed either sequence alone, and 3D FIESTA-c also outperformed 3D TOF-MRA under complete concordance. The combined approach also performed better in the SCA and anterior inferior cerebellar artery (AICA) subgroups. CONCLUSION: The combination of 3D TOF-MRA and 3D FIESTA-c improves preoperative assessment of responsible vessels in PTN, with higher diagnostic accuracy and better agreement with intraoperative findings than either modality alone.