Musculo Skeletal Imaging, CHU Besancon, Besancon, France.
Department of Rheumatology, CHU Besancon, Besancon, France.
RMD Open. 2022 May;8(1). doi: 10.1136/rmdopen-2022-002275.
Differentiating ankylosing spondylitis (AS) from osteitis condensans ilii (OCI) remains challenging for clinicians. The aim of this study was to determine whether Subchondral Bone Attenuation Coefficient of the SacroIliac margins (SBAC-SI) is different in AS, OCI and diffuse idiopathic skeletal hyperostosis (DISH).
A monocentric retrospective observational study was performed at the University Hospital of Besançon. Patients included were followed for AS, DISH or OCI and underwent CT scan including sacroiliac joint. Patients with tumour lesion of bone or a history of pelvic radiotherapy were excluded. AS and OCI patients were matched with a control of the same age and sex. SBAC-SI was evaluated by the sum of 24 identical circular regions of interest, 8 per slice (anterior, middle and posterior).
Thirty AS and AS controls, 31 DISH, 29 OCI and OCI controls were included. SBAC-SI score was 9727 (±2430) in the OCI group (p<0.001), 3563 (±1860) in the AS group, 3899 (±1937) in the DISH group, 4224 (±1693) in the AS control group and 5445 (±1205) in the OCI control group. A threshold of 7500 HU had the best discriminative value between OCI and AS (youden index: 0.89). In AS, disease duration is negatively associated with SBAC-SI (r: -0.623; p<0.01) and HLA B27 is associated with lower SBAC-SI (6523 (5198; 7137) vs 2809 (1568; 3371); p<0.001).
SBAC-SI is significatively different between AS and OCI and could help to distinguish these two diseases.
对于临床医生来说，区分强直性脊柱炎（AS）和骨化性骨炎（OCI）仍然具有挑战性。本研究旨在确定骶髂关节边缘的软骨下骨衰减系数（SBAC-SI）在 AS、OCI 和弥漫性特发性骨肥厚（DISH）中是否不同。
这是一项在贝桑松大学医院进行的单中心回顾性观察研究。纳入的患者接受了 CT 扫描，包括骶髂关节，这些患者随访的疾病包括 AS、DISH 或 OCI。排除了有骨肿瘤病变或骨盆放疗史的患者。AS 和 OCI 患者与相同年龄和性别的对照组相匹配。通过 24 个相同的圆形感兴趣区域的总和来评估 SBAC-SI，每个切片 8 个（前、中、后）。
共纳入 30 例 AS 和 AS 对照组、31 例 DISH、29 例 OCI 和 OCI 对照组。OCI 组的 SBAC-SI 评分为 9727（±2430）（p<0.001），AS 组为 3563（±1860），DISH 组为 3899（±1937），AS 对照组为 4224（±1693），OCI 对照组为 5445（±1205）。7500 HU 的阈值在区分 OCI 和 AS 方面具有最佳的鉴别价值（约登指数：0.89）。在 AS 中，疾病持续时间与 SBAC-SI 呈负相关（r：-0.623；p<0.01），HLA B27 与较低的 SBAC-SI 相关（6523（5198；7137）比 2809（1568；3371）；p<0.001）。
AS 和 OCI 之间的 SBAC-SI 有显著差异，可帮助区分这两种疾病。
