[Clinical value of lymph node sonography]

Percutaneous and endoscopic ultrasound are very useful complementary imaging tools in the detailed assessment of physiological as well as pathological lymph nodes in almost all anatomical regions of the human body. A comprehensive consideration of various features obtained by gray-scale and color Doppler sonography is the basis of the differentiation of benign from malignant lymphadenopathy. Sonographic elastography and contrast-enhanced sonography may provide further information. Nevertheless the sonographic differential diagnosis of enlarged and structurally altered lymph nodes has some limitations. (Endoscopic) ultrasound guided biopsy permits histological diagnosis of pathological lymph nodes with minimal risk, low cost, and high diagnostic accuracy. The sonographical evaluation of lymph nodes is an essential adjunct to the clinical investigation in staging of malignant tumors and lymphoma, in the case of palpable lymph nodes, and in various benign diseases.