Figure 4.

Lymph node anatomy observed by CEUS. CEUS can be used to identify the relation between afferent lymph vessels and draining lymph nodes. Lymph vessels either distribute their content within the lymph node (“filled” nodes, A1-A2) or they go around the lymph nodes without discharging its contents into the node (“hollow” nodes, B1-B2 and C1-C2). In the latter scenario, we always observed a node with a “hollow” appearance (indicated as “H”), followed by a more distant “filled” node (indicated as “F”). Images were obtained from 3 different animals. Where possible, the injection site is pointed out as “i.s.”. Time after microbubble injection is noted on the CEUS images (in min:s).