3D-Slicer-based Diffusion Tensor Fiber Bundle Imaging In Acoustic Neuroma Surgery

Objective:To apply 3D-Slicer diffusion tensor fiber bundle imaging to improve the microsurgical technique and overall treatment of auditory neuroma and reduce the incidence of complications in patients.Methods:Fifty patients with auditory neuroma were grouped by randomization principle(coin toss method)and divided into experimental group(3DSlicer diffusion tensor fiber imaging of the nerve)and control group(routine surgery).patients in both groups had routine preoperative imaging,including temporal bone CT,MRI for T1 WI,T1 enhancement,T2 WI,DWI,FLAIR.the control group underwent surgery routinely.Patients in the experimental group underwent intraoperative microscopy using three methods:multimodal nerve navigation,neurophysiological monitoring,and what the operator saw with the naked eye to clarify the actual location and course of the nerve above the tumor/nerve complex in patients in the experimental group and record it.Patients in the experimental group were also subjected to DTI and FIESTA serial MRI.All patients in the group were operated by the same chief surgeon.Results:1.Preoperative reconstruction of the facial nerve in patients with auditory neuroma was achieved by 3D-slicer software under DTI,and scanning the position of the facial nerve in relation to the auditory neuroma was successful in 24 out of 25 cases.The position of the facial nerve was consistent with what was seen intraoperatively and with the neurophysiological monitoring results,in which the facial nerve was located above the ventral side of the tumor in 3 cases,in the middle of the ventral side of the tumor in 14 cases,and below the ventral side of the tumor in 5 cases.In two cases,the facial nerve was located in the lowermost part of the tumor.In another case,the facial nerve was not shown because the tumor was huge,and the facial nerve was thin and difficult to identify due to the compression,and other interfering signals could not be excluded during the scan;2.The total resection rate of the tumor was about 96%,while the total resection rate of the tumor in the control group was about 88%.The difference between the test group and the control group was not statistically significant(P > 0.05),indicating that there was no significant difference in the degree of tumor resection in the test group compared with the control group;3.The facial nerve function retention rate was evaluated by the House-Brackmann grading method,and the facial nerve function retention rate was 96% in the test group and 68% in the control group at 1 week after surgery;at the follow-up three months after surgery,the facial nerve function retention rate was 96% in the test group and 72% in the control group.The difference in preoperative nerve function between the two groups was not statistically significant(P>0.05),while the difference in facial nerve function between the two groups at 1 week and 3 months postoperatively was statistically significant(P<0.05),indicating that the facial nerve function retention rate in the test group was better than that in the control group.Conclusions:Preoperative use of 3D-slicer diffusion tensor imaging to visualize the facial nerve alignment and its adjacency to the tumor in patients with auditory neuroma can help improve the extent of tumor resection,reduce the rate of facial nerve injury,and improve patients’ quality of life.