Comparison of abdominal computed tomography to ultrasonography in the diagnosis of biliary disease in dogs with acute abdominal signs

Shanna M Marroquin¹Alison M Lee^2*Marc A Seitz²Robert W Wills³Kimberly Ann Woodruff³

• ¹VetCT specialist (United Kingdom), Cambridge, Cambridgeshire, United Kingdom
• ²Department of Clinical Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, United States
• ³College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi, United States

Computed tomography (CT) is growing in popularity for canine patients, yet little information is available comparing the performance of CT to ultrasonography (US) in identifying canine biliary pathology causing acute abdominal signs. The purpose of this study was to compare the performance of CT to US in the diagnosis of canine biliary disease. The hypotheses in this study were that CT would allow for the detection of various canine biliary diseases with similar accuracy to US, and US would be superior to CT for investigation of the bile ducts and diagnosis of cholecystitis due to the small size of these structures. In this prospective, observational study, thirty-five client-owned dogs presenting for acute abdominal signs with a suspicion for biliary disease based on physical exam, complete blood count, and serum chemistry findings received an abdominal US and arterial and venous phase abdominal CT. Two authors reviewed the randomized, anonymized CT and US studies to measure biliary structures and evaluate for biliary pathology. Agreement between each imaging modality and the final clinical diagnoses for biliary pathology was assessed by intraclass correlation coefficients (ICC). Twenty-eight dogs had biliary pathology, and seven dogs served as controls with no evidence of biliary disease. There were variable degrees of good to perfect agreement between US and CT to identify gallbladder mucoceles, gallbladder wall mass, and cholecystitis, moderate agreement when comparing gallbladder wall thickness, and poor agreement to identify cholelithiasis. Findings from this study suggest CT may be used in place of US in canine patients presenting for acute abdominal signs with concern for biliary in origin.