The use of ultrasound for the diagnosis of soft-tissue masses in children.

Forty-four soft-tissue masses in 44 children (age range, 8 months to 18 years) were evaluated with high-resolution ultrasonography. Longitudinal and transverse images were obtained and interpreted within a classification scheme describing the masses as cystic, homogeneous solid, or mixed lesions. Diagnosis was confirmed surgically in all cases, allowing the accuracy of the ultrasound examination to be assessed. Of the 44 masses evaluated, 13 were cystic, 18 homogeneous solid, and 13 mixed masses. Ultrasound alone was independently diagnostic in 11 of 13 cystic masses (ganglions, Baker's cysts) and 12 of 18 homogeneous solid masses (foreign bodies). Ultrasound was useful but not independently diagnostic in six of 18 homogeneous solid masses and in 12 of 13 mixed solid masses and was misleading in three cases. Ultrasonography is a noninvasive, relatively low cost study, not involving radiation or sedation, that supplements the clinical examination and conventional radiography in the evaluation of musculoskeletal soft-tissue masses in children. It provides immediate characterization of mass size, consistency, and anatomic location. Ultrasonography is usually independently diagnostic in lesions such as cysts and foreign bodies and aids in clarifying the diagnosis of fibrous, cartilaginous, vascular, and lymphatic lesions.