小视野DWI在中轴型脊柱关节炎定量评估中的价值

Value of Reduced Field-of-view DWI in Quantitative Assessment of Axial Spondyloarthritis

[目的]探讨小视野弥散加权成像(r-FOV DWI)在中轴型脊柱关节炎定量评估中的应用价值。[方法]前瞻性收集2019年11月至2021年11月间因慢性腰痛、临床怀疑中轴型脊柱关节炎同时行小视野和全视野DWI成像者112例。首先,2名研究者对DWI图像质量进行主、客观评价,主观评估包括图像解剖细节、变形、伪影、整体图像质量的评分,客观评估包括图像信噪比和对比噪声比。然后,相同2名研究者分别在小视野和全视野DWI上测量3组(活动组、非活动组和对照组)的表观扩散系数(ADC)值,评价观察者间的测量一致性,比较ADC值有无差异。绘制两种技术ADC值受试者工作特征曲线并比较曲线下面积(AUC)。[结果]最终纳入102例,根据国际脊柱关节炎协会(ASAS)MRI工作组诊断标准分为3组,其中活动组32例、非活动组29例、对照组41例。小视野DWI图像的主观评分高于全视野DWI[4(3~4)vs.3(3~3),P<0.05];小视野DWI图像的客观评分高于全视野DWI信噪比:6.58(5.05~10.38)vs.4.46(2.37~10.04)对比噪声比:2.04(-1.14~8.29)vs.0.97(-8.19~7.12);P<0.05。两名观察者测量的组间一致性0.60~0.74(ICC相关系数);活动组、非活动组和对照组的ADC值均具有显著差异(P<0.05),小视野DWI测量的ADC值高于全视野DWI。非活动组vs.对照组AUC结果显示,全视野DWI在非活动组vs.对照组中优于小视野DWI,其他组别(病变组vs.对照组、活动组vs.非活动组)两种DWI技术没有统计学差异(P<0.05)。[结论]小视野DWI可用于中轴型脊柱关节炎的定量评估,且其图像主观评分和信噪比较全视野DWI高。

[Objective]To investigate the value of reduced field-of-view DWI(r-FOV DWI)in quantitative assess⁃ment of axial spondyloarthritis.[Methods]A total of 112 patients with chronic back pain or suspected axial spondyloarthri⁃tis receiving full field-of-view DWI(f-FOV DWI)and reduced field-of-view DWI(r-FOV DWI)from December 2019 to December 2021 were enrolled.Next,subjective image quality assessment(anatomical detail,artifacts,distortion,over⁃all image quality)and objective image quality assessment including(signal to noise ratio and contrast to noise ratio)were conducted by two experienced radiologists.In addition,the Apparent Diffusion Coefficient(ADC)values of three groups(active group,inactive group,and control group)on the two DWI sequences were measured by the two radiologists,re⁃spectively.Finally,the consistency of measurement between the two researchers was evaluated and the differences in ADC values was compared.[Results]102 patients were included and were divided into three groups,including the active group(n=32),inactive group(n=29),and control group(n=41)according to ASAS diagnostic criteria.All subjective and ob⁃jective image quality metrics were rated in favor of r-FOV DWI images compared with f-FOV DWI images[overall image quality:DWI 4(3~4)vs.3(3~3)and SNR:6.58(5.05~10.38)vs.4.46(2.37~10.04),CNR:2.04(-1.14~8.29)vs.0.97(-8.19~7.12);P<0.05].Inter-rater consistency of the two researchers were 0.60~0.74.According to the AUC curve,group inactive vs.control showed r-FOV DWI was better than f-FOV DWI.In other groups(lesion vs.control,active vs.in⁃active),there were no differences between both sequences(P<0.05).[Conclusion]The subjective image quality score and signal to noise ratio of r-FOV DWI were higher than those of f-FOV DWI,which could be used for quantitative assess⁃ment of axial spondyloarthritis.