Accuracy of sonographic elastography in the differential diagnosis of enlarged cervical lymph nodes: comparison with conventional B-mode sonography.

OBJECTIVE

The purpose of our study was to evaluate the diagnostic performance of sonographic elastography and B-mode sonography individually and combined in the differentiation of reactively and metastatically enlarged cervical lymph nodes.

SUBJECTS AND METHODS

Eighty-five lymph nodes (metastatic, n = 53; reactive, n = 32) from 37 patients were examined by both elastography and B-mode sonography in this prospective study. Elastographic patterns were determined on the distribution and percentage of the lymph node area with high elasticity (hard), with pattern 1 being an absent or very small hard area to pattern 5, a hard area occupying the entire lymph node. The cutoff line for reactive versus metastatic was set between patterns 2 and 3; patterns 3-5 were considered metastatic. B-mode sonographic diagnosis was based on the sum of scores for five criteria: short-axis diameter, shape, border (regular or irregular), echogenicity (homogeneous or inhomogeneous), and hilum (present or absent). The cutoff line for reactive versus metastatic was set between scores 6 and 7; scores 5 and 6 were considered reactive, and scores 7-10, metastatic.

RESULTS

Sensitivity, specificity, and accuracy of B-mode sonography were 98%, 59%, and 84%, respectively; 83%, 100%, and 89% for elastography; and 92%, 94%, and 93% for the combined evaluation.

CONCLUSION

The combination of highly specific elastography with highly sensitive conventional B-mode sonography has the potential to further improve the diagnosis of metastatic enlarged cervical lymph nodes.