Laloo Frederiek, Herregods N, Jaremko J L, Verstraete K, Jans L
Department of Radiology and Medical Imaging, Ghent University Hospital, De Pintelaan 185, B-9000, Ghent, Belgium.
Department of Radiology & Diagnostic Imaging, University of Alberta Hospital, 8440-112 Street, Edmonton, AB, T6G 2B7, Canada.
Skeletal Radiol. 2018 May;47(5):683-693. doi: 10.1007/s00256-017-2830-3. Epub 2017 Nov 27.
To determine if intra-articular signal changes at the sacroiliac joint space on MRI have added diagnostic value for spondyloarthritis, when compared to bone marrow edema (BME).
A retrospective study was performed on the MRIs of sacroiliac joints of 363 patients, aged 16-45 years, clinically suspected of sacroiliitis. BME of the sacroiliac joints was correlated to intra-articular sacroiliac joint MR signal changes: high T1 signal, fluid signal, ankylosis and vacuum phenomenon (VP). These MRI findings were correlated with final clinical diagnosis. Sensitivity (SN), specificity (SP), likelihood ratios (LR), predictive values and post-test probabilities were calculated.
BME had SN of 68.9%, SP of 74.0% and LR+ of 2.6 for diagnosis of spondyloarthritis. BME in absence of intra-articular signal changes had a lower SN and LR+ for spondyloarthritis (SN = 20.5%, LR+ 1.4). Concomitant BME and high T1 signal (SP = 97.2%, LR + = 10.5), BME and fluid signal (SP = 98.6%, LR + = 10.3) or BME and ankylosis (SP = 100%) had higher SP and LR+ for spondyloarthritis. Concomitant BME and VP had low LR+ for spondyloarthritis (SP = 91%, LR + =0.9). When BME was absent, intra-articular signal changes were less prevalent, but remained highly specific for spondyloarthritis.
Our results suggest that both periarticular and intra-articular MR signal of the sacroiliac joint should be examined to determine whether an MRI is 'positive' or 'not positive' for sacroiliitis associated with spondyloarthritis.
与骨髓水肿（BME）相比，确定骶髂关节间隙在MRI上的关节内信号改变对脊柱关节炎是否具有额外的诊断价值。
对363例年龄在16 - 45岁、临床怀疑患有骶髂关节炎的患者的骶髂关节MRI进行回顾性研究。骶髂关节的BME与关节内骶髂关节MR信号改变相关：高T1信号、液体信号、强直和真空现象（VP）。这些MRI表现与最终临床诊断相关。计算敏感性（SN）、特异性（SP）、似然比（LR）、预测值和检验后概率。
BME诊断脊柱关节炎的SN为68.9%，SP为74.0%，LR +为2.6。无关节内信号改变的BME对脊柱关节炎的SN和LR +较低（SN = 20.5%，LR + 1.4）。同时存在BME和高T1信号（SP = 97.2%，LR + = 10.5）、BME和液体信号（SP = 98.6%，LR + = 10.3）或BME和强直（SP = 100%）对脊柱关节炎的SP和LR +较高。同时存在BME和VP对脊柱关节炎的LR +较低（SP = 91%，LR + = 0.9）。当不存在BME时，关节内信号改变较少见，但对脊柱关节炎仍具有高度特异性。
我们的结果表明，应同时检查骶髂关节的关节周围和关节内MR信号，以确定MRI对与脊柱关节炎相关的骶髂关节炎是“阳性”还是“阴性”。
