Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 JieFang Avenue, QiaoKou District, Wuhan 430030, China.
Rheumatol Int. 2012 Dec;32(12):4005-13. doi: 10.1007/s00296-011-2333-9. Epub 2012 Jan 3.
The objective of this study is to estimate the value of diffusion-weighted MRI (DWI) in the detection of abnormalities in sacroiliac joints in the patients with early ankylosing spondylitis (AS) and investigate the feasibility of whole-body DWI (WB-DWI) in systemic evaluation of AS. Sixteen patients with early AS, 18 patients with simple low back pain (LBP), and 18 healthy volunteers were involved in this study. All subjects underwent conventional MRI and DWI. Apparent diffusion coefficient (ADC) in subchondral bone marrows of sacroiliac joints was measured. Independent-sample t test was used to statistically analyze the difference of ADC values between groups. WB-DWI was performed in additional 12 patients with clinically confirmed AS. The image results were analyzed by multiple post-processing techniques, as compared to conventional MRI. In AS patients, mean ADC values were (0.494 ± 0.170) × 10(-3) mm(2)/s in sacrum and (0.513 ± 0.129) × 10(-3) mm(2)/s in ilium, which were significantly higher than those of LBP ((0.306 ± 0.057) × 10(-3) mm(2)/s in sacrum and (0.323 ± 0.083) × 10(-3) mm(2)/s in ilium) and healthy volunteers ((0.315 ± 0.009) × 10(-3) mm(2)/s in sacrum and (0.319 ± 0.012) × 10(-3) mm(2)/s in ilium). No statistical differences were found between simple LBP and healthy volunteers. Mean ADC value of multiple lesions in AS was (0.932 ± 0.299) × 10(-3) mm(2)/s. By WB-DWI, abnormal signals of sacroiliac joints and extra-sacroiliac joint lesions were demonstrated in the locations corresponding with clinical findings. Mean ADC values of multiple lesions were (1.298 ± 0.323) × 10(-3) mm(2)/s in sacrum and (1.216 ± 0.311) × 10(-3) mm(2)/s in ilium. DWI and WB-DWI were shown to be effective in differentiation and systemic evaluation of early AS. Both techniques are likely to play an importance role in the early diagnosis of AS and assessment of treatment response.
本研究旨在评估扩散加权 MRI（DWI）在检测早期强直性脊柱炎（AS）患者骶髂关节异常方面的价值，并探讨全身 DWI（WB-DWI）在 AS 全身评估中的可行性。本研究纳入了 16 例早期 AS 患者、18 例单纯下腰痛（LBP）患者和 18 例健康志愿者。所有受试者均行常规 MRI 和 DWI 检查。测量骶髂关节软骨下骨髓的表观扩散系数（ADC）。采用独立样本 t 检验对组间 ADC 值的差异进行统计学分析。另外对 12 例临床确诊的 AS 患者行 WB-DWI 检查。采用多种后处理技术对图像结果进行分析，并与常规 MRI 进行比较。在 AS 患者中，骶骨 ADC 值为（0.494 ± 0.170）×10(-3)mm(2)/s，髂骨 ADC 值为（0.513 ± 0.129）×10(-3)mm(2)/s，均明显高于单纯 LBP 组（骶骨（0.306 ± 0.057）×10(-3)mm(2)/s，髂骨（0.323 ± 0.083）×10(-3)mm(2)/s）和健康志愿者组（骶骨（0.315 ± 0.009）×10(-3)mm(2)/s，髂骨（0.319 ± 0.012）×10(-3)mm(2)/s）。单纯 LBP 组与健康志愿者组间 ADC 值差异无统计学意义。AS 多发病灶的平均 ADC 值为（0.932 ± 0.299）×10(-3)mm(2)/s。通过 WB-DWI，可在与临床发现相对应的部位显示骶髂关节和骶髂关节外病变的异常信号。骶骨多发病灶的平均 ADC 值为（1.298 ± 0.323）×10(-3)mm(2)/s，髂骨多发病灶的平均 ADC 值为（1.216 ± 0.311）×10(-3)mm(2)/s。DWI 和 WB-DWI 可有效鉴别和系统评估早期 AS，两种技术均有助于早期诊断 AS 并评估治疗反应。
