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Power Doppler sonography of cervical lymphadenopathy.

AIMS
The supraclavicular region is a common site for tuberculous and metastatic nodes from infraclavicular carcinomas. Grey scale sonographic features differentiating the two have been previously described. However, as power Doppler sonography is now frequently used in the assessment of neck nodes, power Doppler features that may help to differentiate the two are discussed.


MATERIALS AND METHODS
In 78 patients, power Doppler sonograms of nodes involved by metastases from infraclavicular carcinomas (n = 24) and tuberculosis (n = 54) were evaluated. The intranodal distribution of vessels and the intranodal vascular resistance of vessels was assessed and compared. In addition, the power Doppler features of metastatic nodes from infraclavicular carcinomas were compared with metastatic nodes from a head and neck primary (n = 38) such as nasopharyngeal carcinoma (NPC).


RESULTS
Tuberculous nodes frequently demonstrated displaced hilar vascularity or avascularity and the intranodal vascular resistance was low. Metastatic nodes from infraclavicular primaries demonstrated capsular or mixed vascularity and their intranodal resistance was significantly (P < 0.05) higher. In general, metastatic nodes from infraclavicular primaries had a higher intranodal vascular resistance compared to metastatic nodes from NPC, but this was not statistically significant.


CONCLUSION
In the supraclavicular region, the presence of displaced low resistance hilar vascularity or avascularity in nodes is suggestive of tuberculous nodes. Metastatic nodes from infraclavicular primaries have a capsular or mixed vascularity with high resistance.