For those who grew up in the countryside the lymphangiogram might very well remember of the intricate patterns of dried up mucus laid out by snails as they go about their bussiness.
If anything, the lymphangiogram may form just as slow. After puncture of an inguinal lymphnode with a 25G needle lipiodol is slowly injected at a rate of 4-6 ml/hour. It took about half an hour to get to the above image. But fortunately there are ways to speed things up.
FYI these are normal lymphatics. You can also see parenchymal filling of lymphnodes.