title: Injection of the diaphragmatic crus with methylene blue for coloration of the canine thoracic duct.
abstract: OBJECTIVE
  To describe and compare onset and intensity of thoracic duct (TD) coloration after injection of methylene blue into the diaphragmatic crus and mesenteric lymph node.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Adult dogs (n = 18).
  
  
  METHODS
  Methylene blue (≤0.5 mg/kg 1% solution) was injected into the left (n = 9) or right (n = 9) diaphragmatic crus via right 10th intercostal thoracotomy. TD coloration was graded over 10 minutes. A right paracostal laparotomy was then performed in all dogs, and an equal volume of methylene blue injected into a mesenteric lymph node (n = 18). TD color grading was repeated. Statistical analysis was performed on subject weight, volume of contrast agent injected between left and right crus, and number of successful outcomes between diaphragmatic crus injection and mesenteric lymph node injection.
  
  
  RESULTS
  TD coloration occurred in 6 dogs with left crus injection and 4 dogs with right crus injection with obvious staining present in 2 and 3 dogs, respectively. Successful outcome was noted in all dogs with mesenteric lymph node injection. The number of successful outcomes was significantly greater after mesenteric lymph node injection compared with diaphragmatic crus injection (P < .001).
  
  
  CONCLUSIONS
  Methylene blue injected into the diaphragmatic crura and mesenteric lymph node was successful in coloring the TD; however, mean thoracic duct color grade and number of successful outcomes were significantly higher after mesenteric injection.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Bayer
authors.forename: Mauricio
authors.initials: M
authors.lastname: Dujowich
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Krebs
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Leeds
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Anderson
authors.forename: David F
authors.initials: DF
authors.lastname: Merkley
mesh_terms: D000818:Animals; D002916:Chylothorax / Q000601:surgery / Q000662:veterinary*; D003287:Contrast Media; D003964:Diaphragm; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D004285:Dogs; D005260:Female; D007267:Injections / Q000662:veterinary; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008297:Male; D008751:Methylene Blue; D013902:Radiography, Thoracic / Q000662:veterinary; D013897:Thoracic Duct / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media; D008751:Methylene Blue