Automatic Radiographic Quantification of Joint Space Narrowing Progression in Rheumatoid Arthritis Using POC

This paper is an application of image processing techniques for computer-aided diagnosis of Rheumatoid Arthritis (RA). Accurately measuring the progression of joint space narrowing (JSN) is crucial during medical treatment and in imaging biomarkers in clinical trials. In this paper, we analyze sequential radiographic images of patients who have rheumatoid arthritis in hands using image processing techniques. Phase only correlation (POC) is used to detect the progression of JSN between images. A new image processing algorithm is proposed to segment joint images so as to eliminate the mutual interference when measuring the movement of the upper and lower bones by POC. We found that the texture feature on bones will greatly affect the accuracy of POC. Median filter is used to eliminate the effect of texture, and excellent results are obtained in practice. Additionally, the progress of JSN is measured accurately in our method. This can be beneficial for doctors in the identification of disease stages.