Diagnostic accuracy of an integrated approach using conventional ultrasonography, and Doppler and strain elastography in the evaluation of superficial soft tissue lesions

Introduction
To assess the diagnostic accuracy of an integrated approach using conventional ultrasonography, colour Doppler ultrasonography, and elastography strain ratios in tandem in the evaluation of superficial soft tissue lesions.

Material and methods
Sixty-five subjects were included in this prospective cross-sectional study. Greyscale features and Doppler parameters were recorded. Strain elastography of the non-vascular and non-cystic lesions was performed and strain ratios were calculated. Fine-needle aspiration or biopsy of all the lesions was performed depending on their site and condition. Inter-rater k agreement was used to determine the strength of agreement between imaging-based diagnosis and histopathological diagnosis. A diagnostic test was used to calculate the sensitivity, specificity, positive predictive value, and negative predictive value. A p value of < 0.05 was considered statistically significant.

Results
Multiple superficial soft tissue lesions were studied, the majority of which were lipomas, vascular anomalies, and epidermoid cysts. The diagnostic accuracy was very high and varied from 92.31% to 100% for various masses. The imaging-based diagnosis was in agreement with the histopathological diagnosis in 86.15% (n = 56) and disagreement in 13.85% (n = 9) of the cases (p < 0.007). There was very good inter-rater agreement between the imaging-based diagnosis and histopathological diagnosis (κ = 0.818).

Conclusions
The combined use of conventional ultrasonography, colour Doppler, and elastography strain ratios provides a very effective non-invasive tool for the diagnosis of superficial soft tissue lesions and may negate the need for unnecessary biopsies. The advantage of this integrated approach using various ultrasound techniques needs no further emphasis.