Diagnostic quality of percutaneous fine-needle aspirates and laparoscopic biopsy specimens of the liver in rabbits (Oryctolagus cuniculus)

Abstract

Objective—To evaluate diagnostic quality of liver percutaneous ultrasound-guided fineneedle aspirates and laparoscopic biopsy specimens of rabbits (Oryctolagus cuniculus). Design—Prospective descriptive study. Animals—7 healthy adult rabbits. Procedures—3 to 5 liver fine-needle aspirates were obtained with a 22-gauge needle under ultrasound guidance in anesthetized rabbits. Liver biopsy specimens were also obtained with 1.7-mm (n = 2) or 3.0-mm (1) biopsy forceps by direct laparoscopic observation. Fineneedle aspirates were cytologically evaluated on a scale from 0 (suboptimal specimen) to 3 (optimal specimen) for cellularity, cell distribution, cell preservation, cell morphology, and blood contamination. Biopsy specimens were histologically evaluated on a scale from 0 (optimal specimen) to 5 (suboptimal specimen) for artifactual changes; numbers of portal triads and central veins were quantified. Results—Aspirates were moderately to highly cellular (mean, 2.54) with good cell distribution (mean, 2.56), good cell preservation (mean, 2.20), and moderate blood contamination (mean, 1.04). The 1.7-mm biopsy specimens had a mean score of 1.3 for artifactual changes and contained a mean of 0.6 portal triads and 1.6 central veins/biopsy specimen. The 3.0-mm liver biopsy specimens had a mean score of 2.7 for artifactual changes, with a mean of 4.0 portal triads and 4.14 central veins/biopsy specimen. All but one 3.0-mm liver biopsy specimen had ≥ 1 portal triad suitable for histologic evaluation, and all had ≥ 1 central vein; in contrast, only half of the 1.7-mm liver biopsy specimens had a discernible portal triad or central vein. Conclusions and Clinical Relevance—For histologic evaluation, advantages of obtaining 3.0-mm liver biopsy specimens, compared with 1.7-mm liver biopsy specimens or fineneedle aspirates, should be considered in rabbits with suspected liver disease.