Clinical Application of Contrast-Enhanced Ultrasonography in Diagnosis of Superficial Lymphadenopathy

Objective. The purpose of this study was to evaluate the value of contrast-enhanced ultrasonography (CEUS) in differential diagnosis of superficial lymphadenopathy. Methods. Ninety-four superficial enlarged lymph nodes in 94 patients were studied by conventional ultrasonography (gray scale and color Doppler) and CEUS. Contrast-enhanced sonograms were analyzed using contrast-specific quantification software. All of the results were compared with pathologic diagnoses. Results. Of the 94 lymph nodes examined, 44 were benign and 50 were malignant (33 metastases and 17 lymphomas). The sensitivity, specificity, and accuracy of conventional ultrasonography in differential diagnosis between benign and malignant nodes were 51%, 47%, and 55%, respectively. Contrast-enhanced ultrasonography showed intense homogeneous enhancement in 39 of 44 benign lymph nodes, inhomogeneous enhancement in 32 of 33 metastases, and intense homogeneous enhancement and absence of perfusion in 9 of 17 and 6 of 17 lymphomas, respectively. The sensitivity specificity, and accuracy of CEUS were 84%, 79%, and 80%. After time-intensity curve gamma variates were calculated, the area under the curve of the benign lymph nodes was greater than those of the metastatic lymph nodes and lymphomas (P < .01). Conclusions. These results indicate that the use of CEUS and contrast-specific software has a higher degree of diagnostic accuracy than conventional ultrasonography for evaluations of superficial lymphadenopathy. The contrast enhancement patterns and time-intensity curves provide valuable diagnostic information for differential diagnosis of benign and malignant lymph nodes.