Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany.
Department of Internal Medicine II, Experimental Cardiovascular Imaging, University Hospital Ulm, Albert-Einstein-Allee 23, 89081, Ulm, Germany.
Pediatr Rheumatol Online J. 2022 Nov 16;20(1):99. doi: 10.1186/s12969-022-00756-w.
Diagnosing synovial inflammation by administration of gadolinium-based contrast agents is limited by invasiveness and possible side effects, especially in children and adolescents.
We investigated diagnostic accuracy of diffusion-weighted (DWI) MRI with intravoxel incoherent motion (IVIM) imaging compared to contrast-enhanced MRI for detecting synovitis of the knee in a population of pediatrics and young adults. In addition we compared quantitative measures of synovial diffusion and perfusion to a group of healthy volunteers.
In this prospective study, 8 pediatric patients with 10 symptomatic knees (6 girls and 2 boys, mean age 13 years) with known or suspected synovitis underwent pre- and post-contrast 3.0 T MRI of the knee joint and additional DWI sequences between October 2016 and July 2019. For comparison we enrolled 5 healthy young adults (2 women and 3 men, median age 27 years) with contrast-free MRI of both knees. Post-contrast T1w images and DWI images at b = 1000s/mm with apparent diffusion coefficient (ADC) maps of patients were separately rated by two independent and blinded readers with different levels of experience for the presence or absence and degree of synovitis along with the level of confidence. We measured signal intensity on DWI of synovium, joint effusion and muscle with regions of interests and calculated the IVIM-parameters tissue diffusion coefficient (D) and perfusion fraction (f) for patients and volunteers.
All patients showed at least some synovial contrast enhancement, 8 (80%) children knees were diagnosed with synovitis on contrast-enhanced (= ce)-T1w, the diagnostic standard. Ratings by the first and second reader on ce-T1w and DWI showed full agreement (kappa = 1) in diagnosing synovitis and substantial agreement (k = 0,655) for the degree of synovial enhancement. Interobserver agreement on DWI showed fair agreement (k = 0,220) between both readers. Diagnostic confidence was lower on DWI. Mean D- and f-values of muscle was comparable between patients and volunteers. Effusion mean D was higher, mean f was lower, synovial mean D was lower, mean f higher in patients than in volunteers. All differences were statistically significant (p < 0.001).
Diffusion-weighted MRI with IVIM imaging remains a promising, though reader-dependent alternative to i.v. contrast-enhanced imaging in pediatric patients to reliably diagnose, or rule out, synovitis of the knee joint. We detected significantly restricted synovial diffusion and increased perfusion in patients compared to healthy volunteers.
Ethical Comitee University Hospital Ulm, Nr. 320/16.
通过注射钆基对比剂诊断滑膜炎症具有侵袭性，且可能存在副作用，尤其是在儿童和青少年中。
我们通过对比增强 MRI 研究了体素内不相干运动（IVIM）扩散加权（DWI）MRI 对儿科和青年人群膝关节滑膜炎的诊断准确性。此外，我们将滑膜弥散和灌注的定量指标与一组健康志愿者进行了比较。
在这项前瞻性研究中，8 名患有 10 个症状性膝关节（6 名女孩和 2 名男孩，平均年龄 13 岁）的儿科患者接受了膝关节 3.0T MRI 增强前后检查，以及额外的 DWI 序列检查，时间为 2016 年 10 月至 2019 年 7 月。为了比较，我们招募了 5 名膝关节无对比剂的健康年轻成年人（2 名女性和 3 名男性，中位年龄 27 岁）。将患者的增强后 T1w 图像和 b=1000s/mm 的 DWI 图像与 ADC 图分别由两位具有不同经验水平的独立和盲法读者进行评分，以评估滑膜炎症的存在、程度以及诊断信心。我们使用感兴趣区测量滑膜、关节积液和肌肉的 DWI 信号强度，并计算患者和志愿者的 IVIM 参数组织弥散系数（D）和灌注分数（f）。
所有患者均至少存在一些滑膜对比增强，8 名（80%）儿童膝关节在对比增强（ce）-T1w 上被诊断为滑膜炎，ce-T1w 是诊断标准。第一和第二位读者在 ce-T1w 和 DWI 上的评分在诊断滑膜炎方面完全一致（kappa=1），在评估滑膜增强程度方面具有高度一致（k=0.655）。DWI 上的观察者间一致性为两位观察者之间的中等一致（k=0.220）。DWI 的诊断信心较低。患者和志愿者的肌肉 D 和 f 值均值无差异。与志愿者相比，患者的关节积液 D 值较高，f 值较低，滑膜 D 值较低，f 值较高。所有差异均具有统计学意义（p<0.001）。
扩散加权 MRI 联合 IVIM 成像仍然是一种很有前途的方法，尽管对读者有依赖性，但可替代静脉内对比增强成像，用于儿科患者膝关节滑膜炎的可靠诊断或排除。与健康志愿者相比，我们在患者中检测到滑膜弥散受限和灌注增加。
乌尔姆大学医院伦理委员会，编号 320/16。
