BackgroundThe liver sampling technique in dogs that consistently provides samples adequate for accurate histopathologic interpretation is not known.Hypothesis/ObjectivesTo compare histopathologic results of liver samples obtained by punch, cup, and 14 gauge needle to large wedge samples collected at necropsy.AnimalsSeventy dogs undergoing necropsy.MethodsProspective study. Liver specimens were obtained from the left lateral liver lobe with an 8 mm punch, a 5 mm cup, and a 14 gauge needle. After sample acquisition, two larger tissue samples were collected near the center of the left lateral lobe to be used as a histologic standard for comparison. Histopathologic features and numbers of portal triads in each sample were recorded.ResultsThe mean number of portal triads obtained by each sampling method were 2.9 in needle samples, 3.4 in cup samples, 12 in punch samples, and 30.7 in the necropsy samples. The diagnoses in 66% of needle samples, 60% of cup samples, and 69% of punch samples were in agreement with the necropsy samples, and these proportions were not significantly different from each other. The corresponding kappa coefficients were 0.59 for needle biopsies, 0.52 for cup biopsies, and 0.62 for punch biopsies.Conclusion and Clinical ImportanceThe histopathologic interpretation of a liver sample in the dog is unlikely to vary if the liver biopsy specimen contains at least 3–12 portal triads. However, in comparison large necropsy samples, the accuracy of all tested methods was relatively low.

BackgroundBiopsy of the liver evaluates a small portion of tissue, with inferences made to the entire organ. The method and number of biopsies obtained are tempered by consideration of the risks and benefits. Recommendations often include biopsy of more than one liver lobe, although the consistency of histopathology among lobes in dogs is unknown.Hypothesis/ObjectivesTo describe the distribution of histopathologic abnormalities between liver lobes. We hypothesized that discordant results would be evenly distributed among all liver lobes.AnimalsSeventy dogs undergoing necropsy.MethodsProspective study. Liver samples were obtained from all lobes. A primary diagnosis was assigned to each liver sample based on the predominant histopathologic abnormality.ResultsIn this population of dogs, biopsy of at least 2 liver lobes identified the predominant histologic abnormality in 98.6% of the cases. Ten (14%) of the dogs had ≤3 lobes in agreement and could not be assigned a predominant diagnosis. The same diagnosis was present in 6/6 lobes in 39 (56.5%) dogs, 5/6 lobes in 10 (14.5%) dogs, 4/6 lobes in 10 (14.5%) dogs, 3/6 lobes in 7 (10.1%) dogs, and 2/6 in 3 (4.3%) dogs. The number of discordant results did not differ between the liver lobes.Conclusion and Clinical ImportanceThe likelihood of obtaining a sample that is reflective of the predominant histologic abnormality in the liver is increased when multiple liver lobes are biopsied.

Background: Ultrasound examination is commonly used in the diagnostic evaluation of liver disease in dogs. Hypothesis/Objectives: To determine if hepatic sonographic features were predictive of findings on liver histopathology. We hypothesized that there would be a relationship between sonographic features and the category of liver disease based on histologic assessment.Animals: One hundred and thirty-eight dogs in which the liver was evaluated by both abdominal ultrasound examination and histopathologic examination. Twenty-five dogs were included in each of the following categories based on histopathology: normal, degenerative, vascular, inflammatory, and neoplasia. Thirteen dogs had nodular regeneration.Methods: Retrospective study. Medical records of dogs from 2005 to 2010 were searched for cases in which the liver was evaluated by abdominal ultrasound examination as well as by histopathology. After independent evaluation of ultrasound images, the recorded sonographic features were analyzed to identify abnormalities associated with each histopathologic diagnosis or degree of fibrosis.Results: Sixty-four percent of sonographically unremarkable livers had histologic abnormalities. Both microhepatia and the identification of abnormal vasculature were significantly associated with a histopathologic diagnosis of vascular disease. Hepatic masses were significantly associated with a diagnosis of neoplasia. Dilated common bile duct and thickened gall bladder wall were significantly associated with hepatitis. There were no sonographic findings consistently present with hepatic fibrosis.Conclusion and Clinical Importance: Although some ultrasonographic findings, including masses, microhepatia, anomalous veins, and biliary changes, are associated with specific histopathologic abnormalities, sonographic findings are inconsistently detected in many disorders. Overall, hepatic ultrasonographic abnormalities have substantial limitations in predicting the underlying disease.