Usefulness of Endobronchial Ultrasonography Using a Convex Type Probe in Differentiation Between Metastatic Lymph Nodes and Benign Lymph Nodes(Oral 22-3)

Abstract

Background. The convex transducer enables blood flow visualization by power Doppler mode. There is no doubt that power Doppler improves visualization to distinguish between vesseles and other aechoic structures. Another merit to power Doppler is to visualize vessels in a lymph node. In my initial experiences, metastatic lymph nodes of lung cancer have irregularly winding vessels in lymph nodes, and sarcoidosis and malignant lymphoma have straight vessels in the lymph nodes and linear margins of the lymph node. Purpose. We studied 71 lymph nodes visualized by convex bronchoscope. Study objectives were to evaluate whether images of B mode and power Doppler mode may improve the diagnosis of metastatic or benign lymph nodes. Seventy-one lymph nodes visualized by convex bronchoscope sarcoidosis 13 lymph nodes, malignant lymphoma 2 lymph nodes, and metastasis of lung cancer 56 lymph nodes. Results. Of 61 lymph nodes (LNs) without linear hyperechoic lines between LNs, 56 (92%) were metastatic. Fifty-three (95%) of 56 metastatic LNs had aberrant and winding intranodal vessels. In other words, LNs without linear hyperechoic lines and LNs with aberrant and winding intranodal vessels were metastatic. Eight sarcoidosis and 2 malignant lymphoma had hilar straight vessels and linear hyperechoic lines. Conclusion. Irregularly winding vessels and the absence of linear hyperechoic lines were diagnostic factors for metastatic lymph nodes.