中轴型脊柱关节病活动性骶髂关节炎磁共振扩散加权成像意义初探

Evaluation of DWI in detecting active sacroiliitis in patients with axial spondyloarthritis

目的：探讨中轴型脊柱关节病活动性骶髂关节炎磁共振扩散加权成像（ DWI ）的意义。方法对8例经临床和常规MRI确诊为中轴型脊柱关节病活动性骶髂关节炎患者（病例组）及同期11例健康志愿者（对照组）行双侧骶髂关节斜冠位 FSE 序列 T1 WI、STIR 序列 T2 WI、SS-SE-EPI 序列 DWI （ b 值：0，300 s/mm2）扫描。将获得的常规MRI、DWI、表观弥散系数（ ADC）、指数化表观弥散系数（ EADC）图由2名MR诊断医师在工作站盲法分别进行阅片、图像评价及测量各侧骶髂关节旁骨髓ADC值、EADC值并作统计学分析。结果对照组骶髂关节旁骨髓在DWI图上呈均匀稍低信号，ADC图上呈均匀低信号，EADC图上呈均匀高信号。病例组关节旁骨髓水肿灶在 DWI 图、ADC 图上呈高信号， EADC 图上呈低信号。 b 值为300 s/mm2时，病例组各侧骶髂关节旁骨髓水肿灶ADC值均高于对照组，EADC值均低于对照组，差异均有统计学意义（Z＝-3．115、-2．814、-3．002、-3．115、-3．115、-2．714、-2．889、-3．115，均P＜0．05）。结论DWI可以直接观察炎症水肿灶的范围及信号改变，还可以通过ADC值、EADC值对炎症病变水肿程度定量分析，有助于骶髂关节炎的早期诊断和病情活动性的判定。

Objective To evaluate the value of DWI in detecting active sacroiliitis in patients with axial spondyloarthritis （ SpA） .Methods DWI and conventional MRI examinations were done oblique coronary on bilateral SIJs of 19 participants,involving 8 patients （the case group） underwent clinical and conventional MRI evaluation for axial SpA active sacroiliitis and 11 healthy volunteers（the control group）.The conventional MRI,DWI,ADC,EADC images were transmitted to two experienced radiologists respectively to read ,evaluate and measure （ the ADC values and EADC values ） at the workstation under the blind method .The experimental data were inputted and analyzed by statistics software .Results In the control group ,the periarticular bone marrow in the SIJ showed hopyintense signal on the DWI image ,hypointense signal on the ADC image and hyperintense signal on the EADC image .The periarticu-lar bone marrow oedema showed hyperintense signal on the DWI and ADC images , while hopyintense signal on the EADC image.At b values of 300s/mm2 ,the ADC values of the periarticular bone marrow oedema at each side in the case group were significantly higher than those in the control group , while EADC values were lower , the difference were statistically significant（Z=-3.115,-2.814,-3.002,-3.115,-3.115,-2.714,-2.889,-3.115,all P〈0.05）.Conclusion DWI can directly detect the signal changes ,extent of the periarticular bone marrow oedema , and analyze the severity of oedema quantitively ,which shows the utility in determining the activity and early diagnosis .