Ultrasound versus magnetic resonance imaging of soft-tissue lesions: competitive or complementary?

Soft-tissue lumps and bumps are a common referral for imaging in children and adolescents. The etiology of these lesions includes benign non-tumorous lesions, as well as benign and malignant tumors. Some of these lesions have a characteristic imaging appearance but others do not and require tissue sampling to make a diagnosis. MRI typically provides the best overall characterization of soft-tissue masses; however, in some cases US provides complementary information to that provided by MRI that can help make a diagnosis.