T2mapping Quantitative Analysis Of Active Sacroiliitis In The Axial Spondyloarthritis

Objective: To measure the T2 value of the lesion area under the sacroiliac articular surface in patients with axial spondyloarthritis,and to study the ability of T2 m apping to detect early inflammatory lesions and quantitative analysis of inflammatory activity.Methods: A total of 64 patients with axial spondyloarthropathritis(ax-Sp A)diagnosed in our hospital from September 2018 to October 2019 were collected.According to the patient's erythrocyte sedimentation(ESR),C-reactive protein(CRP),and Bone marrow edema on MRI fat suppression sequence,they were divided into the stable condition group(33 cases)and the active condition group(31 cases).A total of 30 healthy subjects and volunteers were collected as the normal group.All subjects were examined with 3.0t MRI routine sequence and T2 mapping sequence,and the region of interest(ROI)was placed on the T2 mapping sequence image by using the image post-processing workstation to measure the T2 value.ESR and CRP of all subjects were recorded.Conduct statistical analysis.SNK test was used to compare the T2 value of the ROI in the diseased active group,the stable group,and the normal group;The paired sample T test was used to compare the T2 value of the diseased area in the diseased stable group and the diseased active group with the T2 value of the normal area around the disease;correlation analysis of Normal distribution data by Pearson.Results:The T2 values in the lesion areas of the sacrum and ilium in the stable group and the active group were higher than the T2 values in the normal group(P<0.05).The T2 values in the interested area of the stable disease group and the active group were significantly different from those in the surrounding relativenormal areas.The T2 value in the lesion area of the sacrum and ilium in the active group was higher than that in the stable group.In the disease activity group,there was a correlation between the T2 value of the lesion area on the sacrum side and the ilium side and ESR and CRP(r>,P<0.05).There was no correlation between T2 value and CRP and ESR in the lesion area on the side of sacrum and the side of bone in the stable condition group(P> 0.05).Conclusion: T2 mapping technique is helpful for early detection of axial spondyloarthropathritis and quantitative analysis of degree of inflammatory activity.