To evaluate the application value of preoperative three-dimensional(3D)multimodal image reconstruction in neuroendoscopic microvascular decompression (MVD).

The clinical data of 48 patients who received neuroendoscopic MVD treatment in Neurosurgery Department of Weifang People′s Hospital from April 2019 to December 2021 were retrospectively analyzed, including 18 cases of trigeminal neuralgia(TN) and 30 cases of hemifacial spasm(HFS). All patients underwent cranial MRI three-dimensional fast imaging employing steady-state acquisition(3D-FIESTA) and three-dimensional time-of-flight magnetic resonance angiography(3D-TOF-MRA) examinations before operation, imaging fusion was performed and reconstruction of nerves, blood vessels and other structures was made. Kappa consistency test was used to evaluate the consistency of the offending vessels, the course of the offending vessels and the contact relationship between the offending vessels and the nerve or the nerve exit/entry brain stem area (REZ), and the degree of pressure of the offending vessels on the nerves seen in the preoperative three-dimensional reconstruction of multi-modal images and neuroendoscopic MVD. According to the TN pain classification or the HFS intensity classification, the improvement of the symptoms of the patients at 1, 3, and 6 months after operation was evaluated.

Preoperative 3D multimodal image reconstruction of 48 patients showed that there were 3 patients whose offending vessels could not be identified and the other 45 patients had clear offending vessels. Neuroendoscopic MVD was successfully completed for all patients, 46 of whom had clear offending vessels. The accuracy of 3D reconstruction of multi-modal images in identifying offending vessels was 91.3% (42/46), the accuracy of judging vascular shape and neurovascular relationship was 93.7% (45/48), and the accuracy of judging the degree of vascular compression on nerve was 100% (21/21). The results of Kappa consistency test showed that the offending vessels, the course and their contact relationship with nerve or REZ, and the degree of vascular compression on nerve were moderately consistent between the 3D reconstruction of multi-modal images and neuroendoscopic MVD(Kappa coefficient: 0.63, 0.74, 0.68, all P<0.001). None of the 48 patients had intracranial infection or recurrence, the median follow-up time was 4 months (1-6 months). The latest follow-up showed that in the case of 18 TN patients, 17 recovered and 1 had partial remission; in 30 patients with HFS, 29 recovered, 1 significantly remission.

Preoperative application of multimodal fusion 3D reconstruction technology can accurately evaluate the offending vessels, the course of offending vessels, their contact relationship with nerve or the REZ and the degree of vascular compression on nerve, which is helpful to improve the accuracy and success rate of neuroendoscopic MVD and effectively reduce the cranial nerve irritation.

Multimodal imaging; Natural orifice endoscopic surgery; Trigeminal neuralgia; Hemifacial spasm; Microvascular decompression; Treatment outcome