title: Measurement of the cardiac silhouette in psittacines.
abstract: OBJECTIVE
  To determine reference values for size of the radiographic cardiac silhouette in healthy adult medium-sized psittacines.
  
  
  METHODS
  Prospective case series.
  
  
  METHODS
  46 African grey parrots (Psittacus erythacus), 7 Senegal parrots (Poicephalus senegalis), and 6 orange-winged Amazon parrots (Amazona amazonica).
  
  
  METHODS
  Birds were anesthetized, and ventrodorsal radiographic projections were obtained. Maximum width of the cardiac silhouette, width of the thorax at the level of the maximum width of the cardiac silhouette, and width of the coracoid were measured on the radiographs. Sternum length was directly measured on individual birds. Results of physical examination, electrocardiography, and echocardiography were normal in all birds.
  
  
  RESULTS
  Mean cardiac silhouette width-to-sternum length ratio was 38%, mean cardiac silhouette width-to-thorax width ratio was 55%, and mean cardiac silhouette width-to-coracoid width ratio was 600%. Width of the cardiac silhouette was strongly correlated with length of the sternum, width of the coracoid, and width of the thorax. No significant differences between species were detected.
  
  
  CONCLUSIONS
  Results suggest that in healthy adult medium-sized psittacines, the cardiac silhouette on a ventrodorsal radiographic projection should be 35 to 41 % of the length of the sternum, 51 to 61 % of the width of the thorax, and 545 to 672% of the width of the coracoid.
authors.affiliation: Department of Small Animal Medicine, Institute for Avian Diseases, University of Leipzig, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Straub
authors.forename: Michael
authors.initials: M
authors.lastname: Pees
authors.forename: Maria E
authors.initials: ME
authors.lastname: Krautwald-Junghanns
mesh_terms: D000818:Animals; D001824:Body Constitution; D004452:Echocardiography / Q000662:veterinary; D004562:Electrocardiography / Q000662:veterinary; D006321:Heart / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D010311:Parrots / Q000033:anatomy & histology*; D011446:Prospective Studies; D013902:Radiography, Thoracic / Q000662:veterinary; D012016:Reference Values