Purpose: To determine the normal
sonographic features of rabbit kidneys with regard
to their use in diagnostic imaging of renal
lesions in this species.
Materials: Twelve
sexually mature clinically healthy New Zealand
White rabbits weighing 2.8 kg to 3.2 kg were
examined after anaesthesia.
Methods: A
diagnostic ultrasound system with microconvex
multifrequency 6.5 MHz probe was used. The animals
were positioned in dorsal recumbency. The
transabdominal paravertebral imaging approach was
used. Longitudinal and transverse scans of the
kidneys were obtained. Six rabbits were
sacrificed, their kidneys removed and studied in
isotonic liquid medium.
Results: The shape
of kidneys was elliptical. The fibrous capsule was
visualized as a straight hyperechoic band. The
fatty capsule was hyperechoic and with irregular
borders. The cortex exhibited a heterogeneous
echogenicity. The acoustic density of the cortex
was lower than that of the liver. The echoicity of
the medulla was lower as compared to the cortex
and the structures of the kidney pelvis. The
latter appeared as a centrally located hyperechoic
structure. The post mortem examination showed that
kidneys were oval and hyperechoic. The kidney
pelvis was seen as a centrally located
longitudinal finding, and the renal hilum – as a
centrally located hyperechoic finding.
Conclusions: The transabdominal paravertebral
approach was a good method for visualization of
rabbit kidneys. The dorsal recumbency of the
subjects allowed the visualization. The in vivo
results corresponded to those from the post mortem
study. The rabbit kidney was oval in shape. The
hypoechoic peripheral zone is occupied by the
cortex and the medulla, while the hyperechoic
central zone – by the kidney pelvis. The cortex
was less echoic than the liver parenchyma. The
kidney pelvic cavity had a lower acoustic density
than its walls, due to the presence of peripelvic
adipose tissue. The present results could be used
in the interpretation of normal and pathological
renal findings in the rabbit.
Key words:
Anatomy, Kidney, Rabbit, Ultrasonography
