Rheumatoid arthritis (RA) is an autoimmune disease that mainly affects the joints of the hand and multiple organs, and early diagnosis and assessment of disease activity are particularly important. We used hyperspectral imaging techniques to evaluate hand performance, evaluate the correlation between surface reflectance and disease activity indicators, and evaluate its predictive value for disease activity.

Patients diagnosed as rheumatoid arthritis from December 2022 to December 2024 were enrolled, the demographic and clinical data of the recruited patients were collected, the disease activity score was calculated, the images were collected by hyperspectral instruments, and the average reflectance of the hand joint surface was counted to analyze its correlation with disease activity. 

A total of 30 active patients, 30 patients in remission, and 30 healthy control groups were included. We found that the hyperspectral images of the hand joint showed that the reflectance peaked at the wavelength of 700-900nm, and there are significant differences in serum CRP levels, erythrocyte sedimentation rate, IL-6, DAS28-CRP, DAS28-ESR, SDAI, CDAI, and 700-900nm hand joint surface reflectance between active and remission patients, and there was no significant difference in the average reflectance of hand joint surfaces between patients in remission and healthy controls, but the reflectance of hand surfaces in active patients was significantly lower than that of healthy controls and remissive patients (p < 0.001), and the average surface reflectance was negatively correlated with CRP, ESR, DAS28-CRP, DAS28-ESR, CDAI and SDAI (p < 0.001). In addition, the optimal cut-off value of average surface reflectance in predicting disease activity was 0. 355 with an area under the curve value of 0.8561 (p < 0.001).

The average reflectance of the hand joint surface measured by hyperspectral technology is related to disease activity, and quantitative data obtained through hyperspectral imaging technology may can evaluate diseases more objectively, which is of great value for evaluating the early disease activity of rheumatoid arthritis.