Lymphangiography of the thoracic duct by popliteal lymph node injection in dogs : An experimental study

Abstract

Chylothorax is a disease characterised by the accumulation of chyle in the pleural cavity. It is a poorly understood disease and can have many congenital or acquired causes. Lymphangiography of the thoracic duct can be a very useful tool in diagnosing chylothorax. Lymphangiography of the thoracic duct is also done before thoracic duct ligation to locate and identify all of its branches and after surgery to control the success of the surgical procedure. Different methods can be used when trying to visualize the thoracic duct. Contrast medium can be injected into the popliteal lymph node, the mesenteric lymph node or directly into a mesenteric lymphatic. The aim of our study was to investigate the practical use of popliteal contrast medium administration and to compare it to other methods like the mesenteric lymph node or mesenteric lymphatic injection. We injected contrast medium into the popliteal lymph node of 4 healthy beagle dogs in an attempt to visualize the thoracic duct in each of the dogs. 10 ml of contrast medium (Imeron 400 (400mg I /ml))b was injected into either the right or left popliteal lymph node with the help of ultrasound guidance. The dogs were put under general anesthesia for the entire procedure. CT images were taken 3-10 minutes after the injection and the animals recovered from anesthesia. We succeeded in all our attempts to visualize the thoracic duct by injection contrast medium into the popliteal lymph node with ultrasound guidance. Failure to visualize the thoracic duct occurred only once when we tried to inject the popliteal lymph node without ultrasound guidance.

Our conclusion is that the method to inject contrast medium into the popliteal lymph node for thoracic duct visualization is a great alternative to the other available methods.