Imaging modalities for evaluating soft tissue masses

In horses, ultrasonography and contrast radiography are useful imaging modalities for evaluating soft tissue masses adjacent to the joint capsule or tendon sheath. Both ultrasound and contrast radiography can differntiate synovial cysts, ganglia, and synovial fistulae. Well-circumscribed soft tissue swellings adjacent to a joint or tendon sheath should be evaluated first via survey radiography. When bone lesions have been ruled out, contrast radiography and ultrasonography are useful in evaluating the soft tissue. Diagnostic differentials for cystic masses located near a joint or tendon sheath include synovial cyst, ganglion, and intersynovial fistula. A synovial cyst can be differentiated from a ganglion by identifying a communication between the soft tissuemass and a synovial structure