In vivo detection of osteoarthritis in the hand with three-dimensional photoacoustic tomography

This paper presents a pilot clinical study in detecting osteoarthritis (OA) in the hand using three-dimensional (3-D) photoacoustic tomography (PAT). Distal interphalangeal (DIP) finger joints from OA patients and healthy volunteers were imaged with our 3-D PAT system in a spherical scanning configuration. Absorption coefficient images of the joint tissue were obtained using our finite element based photoacoustic image reconstruction algorithm coupled with the photon diffusion equation. The recovered quantitative photoacoustic images revealed significant differences in the absorption coefficient of the joint cavity (cartilage and synovial fluid) between the OA and healthy joints. Quantitative analysis of the joints also indicated an apparent difference in the recovered joint spacing between OA and healthy subjects, which is in agreement with the clinical observations. This study suggests that 3D PAT has the potential to become a useful tool for diagnosis of osteoarthritis.