Objective: To evaluate diagnostic quality of liver percutaneous ultrasound-guided fine-needle 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. Fine-needle 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 fine-needle aspirates, should be considered in rabbits with suspected liver disease.