Lymphography of the thoracic duct by percutaneous injection of iohexol into the popliteal lymph node of dogs: experimental study and clinical application.
OBJECTIVE
To evaluate the efficacy of percutaneous administration of iohexol into the popliteal lymph node as a non-invasive technique for thoracic duct lymphangiography in dogs.


METHODS
Experimental study and clinical report.


METHODS
Normal adult dogs (n=4) and 1 dog with recurrent chylothorax.


METHODS
For the experimental study, 4 dogs (weight, 8.4-12.3 kg) had 5-10 mL iohexol injected percutaneously into 1 popliteal lymph node and then thoracic radiographs were taken. Popliteal lymph nodes were examined by histopathology 8 days later. One 25-kg dog with recurrent chylothorax had 25 mL iohexol injected into the right popliteal lymph node followed by thoracic radiography.


RESULTS
In experimental dogs, the thoracic duct was best visualized on thoracic radiographs after administration of 10 mL iohexol. Clinically, no abnormalities were identified in the injected limb and except for 1 dog that had large numbers of siderocytes and erythrophagocytic macrophages in the injected lymph node, the histopathologic findings in the other injected popliteal lymph nodes were not different from contralateral nodes. In the clinical case, the thoracic duct was visualized, but there was leakage of iohexol around the node.


CONCLUSIONS
The thoracic duct in dogs can be visualized by lymphography after percutaneous injection of iohexol (1 mL/kg at 2 mL/min) into the popliteal lymph node.


CONCLUSIONS
Percutaneous popliteal lymph node administration of iohexol should be considered as an alternative to mesenteric lymph node injection for radiographic identification of the thoracic duct in dogs.
Naganobu
Kiyokazu
K
Veterinary Teaching Hospital, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan. a0e303u@cc.miyazaki-u.ac.jp
Ohigashi
Yusuke
Y
Akiyoshi
Tomomi
T
Hagio
Mitsuyoshi
M
Miyamoto
Toru
T
Yamaguchi
Ryoji
R
D000818:Animals; D002916:Chylothorax / Q000000981:diagnostic imaging / Q000662:veterinary*; D003287:Contrast Media / Q000008:administration & dosage*; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000000981:diagnostic imaging*; D004285:Dogs / Q000502:physiology*; D005260:Female; D007267:Injections / Q000662:veterinary; D007472:Iohexol / Q000008:administration & dosage*; D008198:Lymph Nodes; D008220:Lymphography / Q000379:methods / Q000662:veterinary; D008297:Male; D013902:Radiography, Thoracic / Q000379:methods / Q000662:veterinary; D013264:Stifle; D013897:Thoracic Duct / Q000000981:diagnostic imaging* / Q000502:physiology
D003287:Contrast Media; D007472:Iohexol