Comparison of Computed Tomographic and Radiographic Popliteal Lymphangiography in Normal Dogs


  • Presented in part at the European College of Veterinary Surgeons Conference, Helsinki, Finland, July 2010 and the American College of Veterinary Surgeons Symposium Resident Forum, Seattle, WA, October 2010.

Corresponding Author
Brigitte A. Brisson, DMV, DVSc, Diplomate ACVS, Department of Clinical Studies, University of Guelph, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada N1G 2W1


Objective: To (1) describe computed tomographic (CT) popliteal lymphangiography; (2) compare the number of thoracic duct (TD) branches detected by CT and by radiography after popliteal lymphangiography; and (3) to compare the number of branches detected after left and right popliteal lymphangiography.

Study Design: Experimental study.

Animals: Adult dogs (n=6).

Methods: A randomly selected popliteal lymph node was percutaneously injected with 12 mL iodinated contrast medium through a 25-g butterfly catheter over 4–5 minutes. Lateral and ventrodorsal (VD) thoracic radiograph projections and thoracic CT were performed. The procedure was repeated using the contralateral lymph node after a 48–72 hours washout period.

Results: One dog had TD branches visible on CT but not on radiographs. A significantly greater number of TD branches were observed with CT popliteal lymphangiography compared with lateral and VD radiographic popliteal lymphangiography (P=.003 and P<.001, respectively). The number of visible TD branches observed between the 6th thoracic and 1st lumbar vertebrae were not significantly different in these dogs (P=.146). A significant difference in number of TD branches observed was not found after left or right popliteal lymph node injection (P=.097).

Conclusions: CT popliteal lymphangiography consistently identified a greater number of TD branches when compared with radiographic popliteal lymphangiography. Injection of either popliteal lymph node resulted in the same number of TD branches being observed.