Background We used hyperspectral imaging techniques to evaluate the correlation between surface reflectance and disease activity. 

Methods Patients diagnosed as rheumatoid arthritis from December 2022 to December 2024 were enrolled, the disease activity score was calculated, the images were collected by hyperspectral instruments. 

Results 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, the reflectance in active patients was significantly lower than that of healthy controls and remissive patients, the average reflectance was negatively correlated with CRP, ESR, DAS28-CRP, DAS28-ESR, CDAI and SDAI. In addition, the optimal cut-off value of average reflectance in predicting disease activity was 0. 355 with an area under the curve value of 0.8561.

Conclusion The average reflectance of the hand joint surface measured by hyperspectral technology is related to disease activity, which is of great value for evaluating the early disease activity of rheumatoid arthritis.