Maksymowych Walter P
Division of Rheumatology, Department of Medicine, University of Alberta, Edmonton, AB, Canada.
Clin Rheumatol. 2016 Jun;35(6):1447-55. doi: 10.1007/s10067-016-3265-2. Epub 2016 Apr 20.
Plain radiography remains the benchmark for diagnostic evaluation of spondyloarthritis although MRI has much great sensitivity because it can detect a variety of inflammatory lesions as well as fat metaplasia. So, it is the imaging modality of choice when pelvic radiographs are equivocal and especially when important treatment decisions have to be made. Appropriate imaging includes the use of T1-weighted and short tau inversion recovery sequences of the sacroiliac joint in the tilted coronal plane. If there is localized spinal symptomatology, sagittal scans of the spine may also be helpful. However, routine spinal imaging is not recommended. Current consensus designates a positive MRI for classification purposes as requiring the presence of two definite subchondral inflammatory lesions on a single coronal slice or the presence of one such lesion on two consecutive coronal slices. However, such inflammatory lesions can occur in healthy individuals and in those with nonspecific back pain. Erosions are more specific, and their presence can enhance confidence in the diagnosis. MRI, together with CRP, can be helpful in selecting which patients without radiographic sacroiliitis are most likely to respond to tumor necrosis factor inhibitor therapy. The role of MRI in monitoring of patients with SpA remains unclear although it may be helpful in excluding other sources of back pain. A major unanswered question is whether MRI may be useful in predicting relapse following withdrawal of TNFi in patients who have achieved sustained remission.
普通X线摄影仍然是脊柱关节炎诊断评估的标准，尽管MRI具有更高的敏感性，因为它可以检测到各种炎症性病变以及脂肪化生。因此，当骨盆X线片不明确时，尤其是在必须做出重要治疗决策时，它是首选的成像方式。合适的成像包括在倾斜冠状面使用骶髂关节的T1加权和短tau反转恢复序列。如果存在局部脊柱症状，脊柱矢状面扫描也可能有帮助。然而，不建议进行常规脊柱成像。目前的共识是，为了分类目的，MRI阳性需要在单个冠状面上存在两个明确的软骨下炎症性病变，或者在连续两个冠状面上存在一个这样的病变。然而，这种炎症性病变可发生在健康个体以及非特异性背痛患者中。侵蚀更具特异性，其存在可增强对诊断的信心。MRI与CRP一起，有助于选择哪些无放射学骶髂关节炎的患者最可能对肿瘤坏死因子抑制剂治疗有反应。MRI在脊柱关节炎患者监测中的作用仍不清楚，尽管它可能有助于排除其他背痛来源。一个主要未解决的问题是，对于已实现持续缓解的患者，MRI在预测停用肿瘤坏死因子抑制剂后的复发方面是否有用。
