Usefulness of Doppler waveform analysis in differential diagnosis of cervical lymphadenopathy.

We compared Doppler spectral parameters in acute inflammatory, reactive, lymphomatous, and metastatic lymph nodes, and evaluated pulsed Doppler sonography as a method for distinguishing between different causes of cervical lymphadenopathy. Spectral Doppler analysis with measurements of resistance index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end-diastolic velocity (EDV) was performed in 197 patients with cervical lymphadenopathy. Results of Doppler analysis were compared with findings of cytology and histology or with clinical presentation and follow-up. Student's t-test was used to assess statistical significance of differences in Doppler parameters between groups of patients. Significant differences for RI and PI were shown between all groups of patients except between lymphomatous and reactive nodes. Specificity of 100% for metastatic nodal involvement was shown for cutoff values RI>0.80 and PI>1.80. A positive predictive value (PPV) of 100% for acute lymphadenitis was shown for cutoff values RI<0.50 and PI<0.60. An EDV>9 cm/s has 100% negative predictive value for nodal metastasis, and EDV<1 cm/s has 100% specificity and PPV for metastasis. Although there exist differences in RI, PI, PSV, and EDV between different nodal diseases, none of these parameters offer both good sensitivity and good specificity, and only extreme cutoff values may occasionally be helpful in differential diagnosis. Doppler spectral analysis is a valuable noninvasive adjunct which can help in differentiation between metastatic, lymphomatous, acute inflammatory, and reactive lymphadenopathy, but cannot obviate biopsy in the majority of cases.