Abdelhafez Yasser G, Godinez Felipe, Sood Kanika, Hagge Rosalie J, Boutin Robert D, Raychaudhuri Siba P, Badawi Ramsey D, Chaudhari Abhijit J
Department of Radiology, University of California Davis, Sacramento, CA, USA.
Nuclear Medicine Unit, South Egypt Cancer Institute, Assiut University, Assiut, Egypt.
Quant Imaging Med Surg. 2021 Jun;11(6):2333-2343. doi: 10.21037/qims-20-996.
To prospectively demonstrate the feasibility of performing dual-phase SPECT/CT for the assessment of the small joints of the hands of rheumatoid arthritis (RA) patients, and to evaluate the reliability of the quantitative and qualitative measures derived from the resulting images.
A SPECT/CT imaging protocol was developed in this pilot study to scan both hands simultaneously in participants with RA, in two phases of Tc-MDP radiotracer uptake, namely the soft-tissue blood pool phase (within 15 minutes after radiotracer injection) and osseous phase (after 3 hours). Joints were evaluated qualitatively (normal abnormal uptake) and quantitatively [by measuring a newly developed metric, maximum corrected count ratio (MCCR)]. Qualitative and quantitative evaluations were repeated to assess reliability.
Four participants completed seven studies (all four were imaged at baseline, and three of them at follow-up after 1-month of arthritis therapy). A total of 280 joints (20 per hand) were evaluated. The MCCR from soft-tissue phase scans was significantly higher for clinically abnormal joints compared to clinically normal ones; P<0.001, however the MCCR from the osseous phase scans were not different between the two joint groups. Intraclass Correlation Coefficient (ICC) for MCCR was excellent [0.9789, 95% confidence interval (CI): 0.9734-0.9833]. Intra-observer agreement for qualitative SPECT findings was substantial for both the soft-tissue phase (kappa =0.78, 95% CI: 0.72-0.83) and osseous-phase (kappa =0.70, 95% CI: 0.64-0.76) scans.
Extracting reliable quantitative and qualitative measures from dual-phase 99mTc-MDP SPECT/CT hand scans is feasible in RA patients. SPECT/CT may provide a unique means for assessing both synovitis and osseous involvement in RA joints using the same radiotracer injection.
前瞻性地证明对类风湿关节炎（RA）患者手部小关节进行双相SPECT/CT检查的可行性，并评估从所得图像得出的定量和定性测量的可靠性。
在这项初步研究中制定了一项SPECT/CT成像方案，以在RA参与者的两个Tc-MDP放射性示踪剂摄取阶段同时扫描双手，即软组织血池期（放射性示踪剂注射后15分钟内）和骨期（3小时后）。对关节进行定性（正常/异常摄取）和定量[通过测量一种新开发的指标，最大校正计数比（MCCR）]评估。重复进行定性和定量评估以评估可靠性。
四名参与者完成了七项研究（所有四名在基线时进行了成像，其中三名在关节炎治疗1个月后的随访时进行了成像）。总共评估了280个关节（每只手20个）。与临床正常关节相比，临床异常关节在软组织期扫描中的MCCR显著更高；P<0.001，然而，两个关节组在骨期扫描中的MCCR没有差异。MCCR的组内相关系数（ICC）极佳[0.9789，95%置信区间（CI）：0.9734-0.9833]。对于定性SPECT结果，观察者内一致性在软组织期（kappa=0.78，95%CI：0.72-0.83）和骨期（kappa=0.70，95%CI：0.64-0.76）扫描中均很高。
在RA患者中，从双相99mTc-MDP SPECT/CT手部扫描中提取可靠的定量和定性测量是可行的。SPECT/CT可能提供一种独特的方法，使用相同的放射性示踪剂注射来评估RA关节中的滑膜炎和骨受累情况。
