| Objective To investigate the value of DTI in facial nerve reconstruction in patients with acoustic schwannoma,to find the appropriate parameters of DTI images for patients with acoustic schwannoma,and to establish a set of facial nerve fiber bundle reconstruction process.Methods This study prospectively collected the clinical data of 15 patients with acoustic schwannoma who were treated in the Department of Neurosurgery of General Hospital of Ningxia Medical University from July 2021 to March 2023.All patients underwent conventional magnetic resonance sequence scanning and DTI sequence scanning before operation.The relative spatial relationship between tumor and facial nerve was reconstructed by 3D slicer software with DTI technology before operation.The results of DTI reconstruction were compared with the intraoperative microscopic findings,and the location of facial nerve relative to tumor was determined by microscopic observation and electrophysiological stimulation.To evaluate the accuracy of DTI reconstruction of facial nerve in this study.Facial nerve function was evaluated preoperatively and 2 weeks postoperatively using House-Backmann(H-B)classification.Results The facial nerve course was reconstructed by DTI in 15 patients before operation.The facial nerve course through the brainstem and internal auditory canal could be displayed in 15 patients.The facial nerve fibers reconstructed in 1 patient were scattered and the number was small.The results of facial nerve reconstruction in 14 of 15 patients were consistent with the actual position during operation,and the anastomosis rate was 93.33%(14/15).In 1 case,the preoperative reconstruction position was located in the ventral center of the tumor,and the actual position during the operation was located in the ventral inferior.Of the 15 patients,12(80.00%)had total tumor removal under microscope,and 3(20%)had subtotal tumor removal.Facial nerve was anatomically preserved in all patients.The facial nerve function was grade Ⅰ in 10 cases,grade Ⅱ in 4 cases and grade Ⅲ in 1 case before operation,and grade Ⅱ in 10 cases and grade Ⅲ in 5 cases 2 weeks after operation.Conclusion Through intraoperative verification,it is proved that DTI reconstruction of the facial nerve course has a high anastomosis rate with the actual facial nerve course,which is worthy of application.However,it cannot provide a reference for intraoperative assessment of fiber bundle morphology.The preoperative reconstruction of facial nerve with DTI technology can enable the operator to understand the relative position relationship between tumor and facial nerve before operation,and to find facial nerve purposefully during operation,which is conducive to reducing intraoperative nerve damage and protecting facial nerve function. |
