类风湿性关节炎腕关节病变的影像学分析:X线、CT和MR影像对比观察

Comparison of radiography, CT and MR imaging in the detection of abnormal carpal changes accompanying rheumatoid arthritis

目的 比较观察X线平片、CT和MRI在检查类风湿性关节炎 (RA)患者早期腕关节病变中的作用。方法 选取 2 5例RA患者 ,其中女 2 0例 ,男 5例 ,年龄为 2 8～ 70岁 ,平均 4 5 .36岁。临床诊断符合 1987年美国纽约类风湿协会修订的RA诊断标准。为比较观察X线平片、CT和MRI在RA早期诊断中的作用 ,左、右腕分别行CT和MR冠状面扫描。MR成像仪的场强为 0 .3T。扫描时先行平扫 ,扫描序列分别为SET1WI和梯度回波重T2 WI(T2 WI)。然后行增强T1WI作进一步检查。结果 2 5例临床诊断为RA患者的 5 0个腕关节中 ,X线显示骨侵蚀病变者有 14个腕关节 ,MRI检出骨侵蚀病变者有 5 0个腕关节 ;2 5例中行CT检查者有 16例 32个腕关节 ,其中 2 2个腕关节有骨侵蚀病变。MRI共检出 16 4处腕骨的骨侵蚀病灶 ,而X线平片仅检出 2 1处腕骨骨侵蚀病灶 ,CT检出 6 8处骨侵蚀病灶。月骨是最易受累的部位 ,其X线、CT和MR的检出率分别为 6 .0 %、2 8.1%和5 4 .0 %。在类风湿关节炎骨质侵蚀病变的检出上 ,3种检查方法之间经两两比较分析 ,差异均有非常显著性意义 (P值均 <0 .0 1)。MRI不仅可显示RA早期CT和X线所不能显示的腕部骨质侵蚀改变 ,还可显示滑膜炎性及水肿改变 ,增强MRI可鉴别血管翳与关节积液。

Objective To compare magnetic resonance (MR), computed tomography (CT), and radiography in the detection of early abnormal carpal changes in patients with rheumatoid arthritis (RA). Methods Twenty-five patients, aged from 28 to 70 years (mean age 45.36 years, 5 men and 20 women), were recruited.RA was diagnosed in all patients by the ARA′s criteria.All patients underwent radiography and MR examination on both wrists.CT examinations were performed on both wrists in 16 of 25 patients.For each patient, the examinations of radiography, MR or CT were obtained within one day.In precontrast MR examination, spin-echo T 1 and gradient echo with rephasing T 2* images were obtained using a 0.3-T imager on both wrists respectively.Then, one of the both wrists with more noticeable erosion was chosen for postcontrast MR examination using the same precontrast T 1 sequence.Results Of the 50 wrists in 25 patients, carpal erosions were observed in 14 wrists by radiographs, in 22 wrists by CT (16 patients), and in 50 wrists by MR.In 25 patients, 164 carpal erosive foci were demonstrated by MR and only 21 foci were revealed by radiographs, also 68 foci were revealed by CT in 16 patients.Significant differences were found between radiography and either CT (P<0.001) or MR (P<0.001), and between CT and MR (P< 0.001).The lunate was the most frequent affected carpal bone.6% erosive lunates were demonstrated by radiography, 28.1% by CT, and 54% by MRI.MR imaging was able to reveal some early erosive changes, which could not be found by either CT or radiography.Enhanced MR could further differentiate edema from erosion within carpal bones.Conclusion Either MRI or CT is superior to conventional radiography in detection of abnormal carpal changes in patients with RA.For patient suspected of RA and who have normal or questionable results on hand (including wrist) radiography, or for monitoring the treatment of RA, further wrist MR or CT examination should be advisable in RA patient for early diagnosis or treatment.