Perry David, Stewart Neal, Benton Nick, Robinson Elizabeth, Yeoman Sue, Crabbe Jeff, McQueen Fiona
Departments of Rheumatology and Radiology, Auckland District Health Board, Auckland University, Auckland, New Zealand.
J Rheumatol. 2005 Feb;32(2):256-67.
To compare the detection and scoring of erosions in patients with rheumatoid arthritis (RA) using magnetic resonance (MR) and multidetector helical computerized tomographic (CT) scanning.
Comparative CT and MR scans of the dominant wrist were obtained from 9 patients with RA and clinical examination was performed to assess disease activity. MR and CT scans were scored for erosions and MR scans for bone edema by 2 radiologists using a validated system. Radiographs of the hands and feet were also scored for erosions using the modified Sharp score.
In 117 of 135 (87%) sites there was concordance for erosions between MR and CT scans. At the remaining 18/135 sites (13%), erosions were identified by CT but not MR in 12/135 (9%) and by MR but not CT in 6/135 (4%). Partial volume artefacts on MR images and shifts in slice position were the most common reasons for erosion mismatch between MR and CT. The mean CT bone erosion score was significantly higher than the MR erosion score when individual bony sites were examined (p = 0.024), with the greatest difference being at the metacarpal bases. The total bone erosion score also tended to be higher on CT than MR [median scores of 20 (range 0-66) and 12 (0-51), respectively; p = 0.060]. MR and CT erosion scores correlated strongly with the total Sharp score (r = 0.93, p = 0.0002 and r = 0.94, p = 0.0002, respectively) and with the Disease Activity Score (MR: r = 0.77, p = 0.02; CT: r = 0.71, p = 0.03).
Most erosions were detected using both modalities, but erosion scores were higher on CT than MR scans, especially at the metacarpal bases. It is possible that small erosions in some regions are more easily detected by CT because of its ability to clearly delineate cortical bony margins.
比较磁共振成像（MR）和多排螺旋计算机断层扫描（CT）在类风湿关节炎（RA）患者中对侵蚀的检测及评分情况。
对9例RA患者的优势腕关节进行CT和MR对比扫描，并进行临床检查以评估疾病活动度。由2名放射科医生使用经过验证的系统对MR和CT扫描的侵蚀情况以及MR扫描的骨水肿情况进行评分。同时使用改良Sharp评分对手足X线片的侵蚀情况进行评分。
在135个部位中的117个（87%），MR和CT扫描在侵蚀情况上具有一致性。在其余18/135个部位（13%），12/135个部位（9%）的侵蚀在CT上被识别但在MR上未被识别，6/135个部位（4%）的侵蚀在MR上被识别但在CT上未被识别。MR图像上的部分容积伪影和层面位置偏移是MR与CT之间侵蚀不匹配的最常见原因。当检查单个骨部位时，平均CT骨侵蚀评分显著高于MR侵蚀评分（p = 0.024），最大差异出现在掌骨基部。CT上的总骨侵蚀评分也往往高于MR [中位数评分分别为20（范围0 - 66）和12（0 - 51）；p = 0.060]。MR和CT侵蚀评分与总Sharp评分（分别为r = 0.93，p = 0.0002和r = 0.94，p = 0.0002）以及疾病活动评分（MR：r = 0.77，p = 0.02；CT：r = 0.71，p = 0.03）密切相关。
两种检查方式均可检测到大多数侵蚀，但CT扫描的侵蚀评分高于MR扫描，尤其是在掌骨基部。由于CT能够清晰勾勒皮质骨边缘，某些区域的小侵蚀可能更容易被CT检测到。
