Computed Tomographic Findings of Liver Cirrhosis in Dogs: Comparison between Compensated and Decompensated Cirrhosis

Simple Summary Cirrhosis is the end-stage of chronic hepatitis, characterized by the replacement of hepatic parenchyma with fibrous tissue and regenerative nodules. In cirrhotic livers, reduced hepatic function and interference with portal blood flow cause sinusoidal portal hypertension, resulting in secondary complications such as varices, ascites, and hepatic encephalopathy. In human medicine, computed tomography (CT) is the most sensitive diagnostic imaging technique used to evaluate hepatic morphological change. However, there is limited information on the CT features of cirrhosis in dogs. This study aimed to describe the CT characteristics of histologically confirmed cirrhosis and to compare these characteristics between compensated and decompensated cirrhosis. The results of this study can aid clinicians in diagnosing cirrhosis and predicting the progression of cirrhosis to the decompensated phase.Abstract This study aimed to describe computed tomography (CT) characteristics of histologically confirmed cirrhosis and to compare these CT characteristics between compensated and decompensated cirrhosis. Sixteen dogs who underwent contrast CT and histopathological examinations were included; eleven dogs were assigned to the compensated group, and five dogs were assigned to the decompensated group. Irregular hepatic contours with a diffuse nodular distribution and hepatic lymph node enlargement are common concomitant features of cirrhotic livers on CT images. The enhancement patterns of the regenerative nodules and hepatic parenchyma were not significantly different from each other. Hypoattenuating areas with delayed contrast enhancement indicating fibrotic tissue were confirmed in 56.3% of cases. Hypoattenuating wedge-shaped area or nodule with minor or no contrast enhancement (histopathologically confirmed as focal necrosis) were confirmed in 37.5% of cases. Among CT variables, only normalized liver volume and portal vein-to-aorta ratio were significantly lower (p = 0.038 and 0.003, respectively) in the decompensated group. In conclusion, this study presented the CT features of cirrhosis and identified CT features that can discriminate between compensated and decompensated cirrhosis. Specifically, lower normalized liver volume and the portal vein-to-aorta ratio might be useful indicators for the progression of cirrhosis to the decompensated phase.