Figure 12: The figure depicts preliminary data of a mouse tibiotalar joint without CIA induction (a) and one at 1 week after RA induction (b). Both images have the capsule and soft tissue intact (imaged from outside the joint) generated for this proposal. The skin was removed to simulate subcutaneous imaging as a potential approach. In (a), no distorted architecture is seen. The red arrow is the cartilage surface with the synovial space above (black, minimal signal). The black gap just below the cartilage is subchondral bone. The green circle is a large synovial space and the blue a tendon. The banding in the tendon is from the highly organized collagen. The orange arrow is synovium. In Figure 3(b), 1 wk after CIA, the orange circle is synovial hypertrophy and pannus formation. Note the increased back-reflection intensity relative to (a), consistent with cellular infiltration. The red arrow is thickened cartilage (swollen in early arthritis). The subchondral bone (yellow arrow) is wider with more diffuse bone below it (edema). The green arrow is soft tissue swelling outside the joint. (Unpublished results.)