Subacromial subdeltoid (SASD) bursitis on MRI can have a number of appearances. In this case we have a nodular type of synovitis which should raise the possibility of an inflammatory arthritis as a cause (Rheumatoid Arthritis in this case).
Fluid in the subdeltoid bursa (Pink arrow). Synovial thickening (Blue arrow)seen as nodular intermediate signal changes in the bursa.