[Analysis of cervical metastatic lymphadenopathy by ultrasonography]

One hundred and eight cervical lymph nodes of 37 patients were evaluated by ultrasonography. All lymph nodes were examined histologically, and among them 63 lymph nodes were metastatic nodes. If submandibular, submental, mid and inferior internal jugular lymph nodes larger than 8 mm, and superior internal jugular lymph nodes larger than 9 mm had been regarded as metastasis, high sensitivity (92%) was demonstrated. All of 31 lymph nodes with unclear or irregular margin were metastatic. Eccentric hyperechoic area, which was considered to be the hilus of the lymph node, was observed in 20 nodes. Those were non-metastatic lymph nodes. Otherwise, all of 48 lymph nodes with inhomogeneous internal echoes or with central hyperechoic area and peripheral hypoechoic zone were metastatic. The in vivo and in vitro ultrasonograms of 25 lymph nodes were compared with histopathological findings. The metastatic region was not differentiated with the remaining area of the lymph node by ultrasonography. Necrosis showed an-, hypo-, iso-, or hyperechoic. Fibrosis showed iso- or hyperechoic. Inhomogeneous internal echoes were proved to be necrosis and fibrosis, and such a lymph node was metastatic. The eccentric hyperechoic area of the non-metastatic lymph node was attributed to fatty tissue. Ultrasonography was a useful examination for evaluating cervical lymph nodes.