A small soft-tissue mass near a tendon sheath that is a cystic lesion containing gelatinous fluid is most accurately called a

• A. Ganglion cyst
• B. Synovial cyst
• C. Hematoma
• D. Abscess

Answer: (A)

A ganglion cyst is the best fit. These are benign, mucin-filled cystic lesions that arise from a joint capsule or tendon sheath and contain a gelatinous, jelly-like fluid. Their typical presentation is a small soft-tissue mass near a tendon sheath, often with a well-defined wall and simple fluid content on imaging, sometimes showing posterior acoustic enhancement and no internal vascularity on Doppler. This gelatinous, mucinous fluid distinguishes them from a hematoma, which is a blood collection and can have mixed echogenicity depending on age and history, and from an abscess, which usually contains pus, may have a thick irregular wall, surrounding edema, and signs of infection. A synovial cyst can be similar in location, but the characteristic gelatinous content and common association with tendon sheaths make the description most consistent with a ganglion cyst.