Quantitatively Analyze In Diffusion Tensor Imaging Based On SCT The Spinal Cord Fiber Tracts Of Cervical Spondylotic Myelopathy Injury

Objective:To explore law of change in the microstructure of spinal cord compression and different white matter fiber tracts in patients with spinal cord cervical spondylosis by using spinal gray matter segmentation,diffusion tensor magnetic resonance imaging technology,and quantitative microstructure analysis based on template atlas of the Spinal Cord Toolbox(SCT)software.Methods:32 clinically diagnosed CSM patients(patient group)and 13 healthy volunteers(control group)with age,gender matched were collected in the third affiliated hospital of Nanchang University during July 2019 to December 2019.All patients underwent spinal cord 3D T1,T2~*WI and DTI scan.The degree of spinal stenosis was graded.The SCT-based PAM50 template map registration and segmentation method was used to evaluate the DTI of different white matter fiber tracts.Compare whether the FA value of white matter fiber tracts in different segments of healthy control group is different,and whether the FA value of different fiber tracts in the same segment is different.And compare the difference in FA value between the CSM patient group and the control group in the same fiber bundle region in the same segment.Statistical analysis was performed by SPSS Statistics(IBM SPSS Statistics25)software.Differences in FA values of different spinal tracts at C3,C4,C5,and C6levels were compared using between-groups and intra-group variance analysis.Using independent sample t tests on spinal cord tracts at different levels between two groups,p<0.05 is considered statistically significant.Results:Among CSM patients:Seven cases were single-segment compression.25 cases were multi-segment compression,of which C2/3 was 1 case,C3/4 was 20 cases,C4/5was 25 cases,C5/6 was 24 cases,C6/7 was 5 cases.No signal of spinal cord degeneration was seen(T2WI high signal).The degree of compression is based on the grading system proposed by Kang Y et al.,which is divided into 44 mild(grade 1)segment and 31 moderate(grade 2)segment.Control group:FA value of white matter fiber bundles in different segments of cervical spinal cord are different:analysis of variance of upper and lower horizontal spinal cord bundles:F=5.321,p=0.003<0.05;analysis of variance of different bundles at the same level:F=20.365,p<0.05.Control group:FA values of white matter fiber tracts in different segments of the cervical spinal cord are different:with the spinal cord continues downward,the FA values of most fiber tracts gradually decrease,but the anterior bundle of the spinal cerebellum is opposite.FA values in different white matter regions of the same segment of the cervical spinal cord are different.Patient group vs.control group:The C3 segment-mild stenosis group had significantly lower FA values on the left ventrolateral reticular spinal tract,the left vestibular spinal tract,the left cortical spinal anterior tract,and the left parietal spinal tract.In C5 segment-mild stenosis group,the FA value of the left red nucleus spinal cord bundle and the left reticular spinal cord bundle were significantly reduce.In C6 segment-mild stenosis group,the FA value of the left spinal cord olive bundle decreased;In C4 segment-moderate stenosis group,FA values of the bilateral reticular spinal cord bundle,the left lateral vestibular tract,the right ventral reticular spinal tract,the bilateral cortical spinal anterior tract,and the left parietal spinal tract were significantly reduced.Conclusion:Cervical spinal cord fiber tracts have different microstructures at different levels;different spinal bundle regions at the same level also have different microstructures.With the same degree of stenosis,the damage of different segments is different.The same degree of mild stenosis,C3 is more likely to emit microstructural changes than other segmental white matter fiber tracts.For moderate stenosis,C4 is more prone to microstructural changes than other segments of white matter fiber tracts than other segments.The area of injured fiber tracts is mainly concentrated on the ventral side(ventrolateral reticulospinal tract,ventral corticospnal tract,tectospinal tract,lateral vestibulospinal tract,rubrospinal tract,lateral reticulospinal tract,spino-olivary tract,ventral reticulospinal tract).Quantitatively analyze in DTI based on SCT the white matter fiber tracts of cervical spondylotic myelopathy may provide a certain reference value for the evaluation of the disease and the prediction of the efficacy.