RESUMO
The purpose of this study is to evaluate the usefulness of power Doppler sonography in differentiating metastatic from non-metastatic cervical lymph nodes in patients with head and neck cancer. Histologically proved metastatic [n=48] and non-metastatic [n=110] lymph nodes were examined with power Doppler sonography in 52 patients with head and neck cancer. Power Doppler sonography was assessed for its ability to differentiate metastatic from non-metastatic lymph nodes. Power Doppler sonography showed characteristic features of parenchymal blood, flow signal in 40 [84%] of the 48 metastatic lymph nodes. On the Other hand, only two [2%] of the 110 non-metastatic nodes showed these power Doppler signals. In addition, power Doppler sonography showed high levels of sensitivity [83%] and specificity [98%] in depicting metastatic lymph nodes, which were superior to the value [66% sensitivity and 92% specificity] obtained by applying size criteria [L/S ratio: long axis short axis ratio of the enlarged lymph node]. Our results suggest that the power Doppler criteria combined with the size criteria [L/S ratio] constitute a powerful tool in differentiating metastatic from non-metastatic lymph nodes in patients with head and neck cancer