Lymph node enlargement is the commonest cause of a neck lump. High-resolution ultrasound (US) combined with fine needle aspiration cytology (FNAC) has a high sensitivity & specificity in the assessment of cervical lymph nodes. Grey scale sonography helps to evaluate the morphology of cervical nodes, whereas power Doppler sonography assesses nodal vasculature. Grey scale sonographic features such as internal architecture, presence of intranodal necrosis, echogenic hilus, and calcification help to distinguish between the various causes of cervical lymphadenopathy. The presence of adjacent soft tissue edema and matting of nodes are additional useful features to identify tuberculous lymphadenitis. Power Doppler sonography evaluates the vascular pattern of the lymph nodes and further improves the diagnostic accuracy of sonography in differentiating benign from malignant nodes. Metastatic nodes exhibit disorganized peripheral vessels, lymphomatous nodes are invariably hypervascular with chaotic internal vascularity while tuberculous nodes are avascular or hypovascular with displaced hilar vessels.

Apart from the role in diagnosis, ultrasound helps in the surveillance of the post-treatment neck for presence of nodal recurrence and to monitor treatment response in patients undergoing chemotherapy or radiotherapy. The increasing use of ultrasound contrast further enhances the role of sonography in these areas.

This presentation aims to provide an overview of sonographic evaluation of cervical lymph nodes and its use in the post-treatment neck.