Ultrasonographic diagnosis of extremity masses.

Radiographic examination of soft tissue extremity masses is frequently inconclusive. In 18 patients with normal or nonspecifically abnormal radiographs, gray scale ultrasonography provided useful additional information. It was possible to distinguish fluid collections from solid masses, and recurrent venous thrombosis from hematoma in anticoagulated patients. Occasionally, specific diagnoses were suggested on the basis of ultrasonic morphologic characteristics. Diagnoses included soft tissue neoplasms, hematomas, aneurysms, synovial cysts, abscesses, and a lymphocele. Ultrasonically guided percutaneous needle aspiration was diagnostic to two cases. Features of differential diagnostic value relative to extremity solid masses and fluid collections are discussed. Ultrasonography is useful in evaluating these soft tissue masses.