Spectral Doppler Sonography of Musculoskeletal Soft Tissue Masses

Objective. To determine whether resistive indices obtained from spectral Doppler waveforms can be used to distinguish benign from malignant musculoskeletal soft tissue masses. Methods. A retrospective review of Doppler sonograms was performed for 52 patients with 53 soft tissue masses. All masses showed internal flow on color or power Doppler sonography, and spectral Doppler sonography yielded waveforms from which resistive indices were calculated. This information was analyzed along with the histologic diagnosis of each lesion with significance set at P > .05. Results. There were 19 benign lesions and 34 malignancies. The resistive indices of the benign masses ranged from 0.44 to 1.0 (mean ± SD, 0.72 ± 0.42), whereas the malignant masses had resistive indices ranging from 0.28 to 1.0 (mean, 0.62 ± 0.36). There was no statistically significant (P > .05) difference between the resistive indices of benign and malignant lesions. Conclusions. Resistive indices cannot be used to distinguish benign from malignant musculoskeletal soft tissue masses.