title: Comparison of computed tomographic and radiographic popliteal lymphangiography in normal dogs.
abstract: 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.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Adult dogs (n=6).
  
  
  METHODS
  A randomly selected popliteal lymph node was percutaneously injected with 12 L 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.
authors.affiliation: Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
authors.forename: Ameet
authors.initials: A
authors.lastname: Singh
authors.forename: Brigitte A
authors.initials: BA
authors.lastname: Brisson
authors.forename: Stephanie
authors.initials: S
authors.lastname: Nykamp
authors.forename: M Lynne
authors.initials: ML
authors.lastname: O'Sullivan
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage*; D004285:Dogs / Q000033:anatomy & histology*; D007472:Iohexol / Q000008:administration & dosage*; D008198:Lymph Nodes / Q000473:pathology*; D008220:Lymphography / Q000379:methods / Q000662:veterinary*; D013897:Thoracic Duct / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000662:veterinary*
chemical_list: D003287:Contrast Media; D007472:Iohexol