Neurovascular compression syndromes including trigeminal neuralgia (TN) and hemifacial spasm (HFS) are caused by neurovascular conflicts at the root entry zone of the corresponding cranial nerves in the posterior fossa. Microvascular decompression (MVD) is the best choice for the treatment of TN and HFS. An accurate delineation of the responsible vessel could decrease the rate of possible operative complications such as nerve paresis.

In this study, three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) and three-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA) were performed on 113 patients with TN or HFS. The imaging data were compared to the intraoperative findings and the accuracy of the data was calculated among the different responsible blood vessels and disease types. The accuracy of the data among different genders, disease durations, disease sides, and disease types was also calculated to identify the target patients for the preoperative diagnostic approach with 3D-FIESTA combined with 3D-TOF MRA.

The accuracy of detection with the imaging was above 75% in cases with single-vessel compression. Among these, the accuracy of the preoperative imaging result was the highest when the lesions were in the superior cerebellar artery (SCA; 91.1%). In cases of multiple-vessel compression, however, the coincidence between the preoperative and intraoperative results was only 30.0%. In most of the cases of TN, the responsible blood vessels were in the SCA, and the accuracy in the SCA reached 94.9%. In HFS patients, the responsible blood vessels were in the anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA), and the accuracy was 86.8% and 90.0%, respectively. The differences in the accuracy of the data among different genders, disease durations, disease sides, and disease types were not statistically significant.

This study verified the clinical instructional value of 3D-FIESTA combined with 3D-TOF MRA in MVD, and showed that this preoperative examination is reliable for all genders, disease durations, disease sides, and disease types.