磁共振常规序列与3D-WATS对强直性脊柱炎骶髂关节炎分级的对比研究

目的本研究应用3.0 T MRI常规序列与三维水选择成像序列(3D-WATS)对强直性脊柱炎(AS)骶髂关节炎进行分析,探讨MRI常规序列与3D-WATS对AS骶髂关节炎分析的优势对比及分级差异。方法收集2015年1月~2016年6月经临床确诊的AS患者42例,均行3.0 T MRI骶髂关节平扫序列,包括T1WI、T2WI SPAIR、T1WI-Cor、T2WICor、T2WI-Cor-SPAIR和3D-WATS,分别观察血管翳增多、骶髂关节软骨异常、骨髓水肿、脂肪沉积、关节面增生硬化及关节骨质融合等征象,同时根据MRI AS骶髂关节炎分级方法分别对常规序列组及常规序列加3D-WATS组所观察征象进行分级,然后对其分级结果进行统计学分析。结果 42例AS骶髂关节炎患者常规序列上主要表现为关节面下骨髓水肿、脂肪沉积、软骨骨质硬化、破坏、关节间隙不均匀变宽,部分变窄,直至关节基本完全性强直或完全强直。3D-WATS主要表现为骶髂关节软骨的破坏,早期的形态略扭曲、不连续,可疑破坏,进而局部缺损,厚薄不均及血管翳增多,中晚期软骨连续性破坏,丧失正常形态,仅可见斑点状残存软骨,同时骶侧、髂侧软骨与二者分界不清,直至软骨破坏完全。常规序列对骶髂关节软骨显示不佳,无法对其结构进行具体分析,而3D-WATS可以清晰的显示软骨形态、信号异常,常规序列组与常规序列加3D-WATS组对AS骶髂关节炎分级中0级、Ⅰ级分级具有统计学差异(P0.05),Ⅱ级及以上无统计学差异,因而3D-WATS对早期AS骶髂关节软骨病变的敏感度高于常规序列。结论 MRI常规序列能够显示AS骶髂关节炎整体病变,3D-WATS能够很好的显示软骨病变,由于3D-WATS对早期AS骶髂关节软骨病变的敏感度高于常规序列,因而常规序列与3D-WATS联合应用能够较为准确的对AS骶髂关节炎进行分级评价,特别是对早期病变进行准确诊断。

Application of 3D-WATS in the MRI diagnosis of sacroiliitis in ankylosing spondylitis

Objective To analyze the ankylosing spondylitis (AS) sacroiliac arthritis, and to compare the 3.0 T MRI fea-tures on conventional sequences and 3D water imaging sequence (WATS) of sacroiliitis in ankylosing spondylitis. Methods 42 pa-tients diagnosed with AS from January 2015 to June 2016 underwent MRI examination including T1WI, T2WI SPAIR, T2WI, and 3D WATS. The pannus, sacroiliac articular cartilage abnormality, bone marrow edema, fat deposits, articular surface sclerosis and anky-loses were recorded. The sacroiliac articular cartilage abnormality on the conventional sequence and 3D-WATS was compared. Re-sults The main MRI findings were subchondral bone marrow edema, fat deposits, cartilage sclerosis, destruction, irregular joint space narrowing or widening, and joint ankylosis. The 3D-WATS showed initial cartilage irregularity and interruption progressing to local defects, heterogeneous thickness and increasing pannus, and in the late stage continuous/complete cartilage destruction. The sacroiliac joints were not visualized well on conventional sequences whereas the 3D-WATS depicted clearly the cartilage morpholo-gy. The 3D-WATS had significantly (P<0.05) higher sensitivity than conventional sequences in the diagnosis of early grade 0-1 sacroiliitis. Conclusion The 3D-WATS demonstrates the cartilage abnormality in sacroiliitis better than conventional sequences.