[Doppler US of the urinary system and renal vessels in normal and pathologic conditions]

Renal evaluation with B-mode and Doppler ultrasound in captive tufted capuchins (Sapajus apella)

BACKGROUND

This study aimed to evaluate, by B-mode ultrasound and Doppler ultrasound, the kidneys of one Neotropical primate maintained in captivity.

METHODS

Ten adult intact tufted capuchins (Sapajus apella) were evaluated. The morphometric parameters of both kidneys were evaluated and kidney volumes calculated. Color Doppler was used to evaluate renal vascular architecture and to identify arteries of the left kidney. Spectral Doppler was used to measure peak-systolic velocity, end-diastolic velocity, and resistive index (RI).

RESULTS

Both kidneys presented homogeneous cortical echogenicity and homogeneous echotexture with preserved corticomedullary differentiation. There was no statistically significant difference between right and left kidneys for all morphometric parameters. RI of the left renal, interlobar, and arcuate arteries were, respectively, 0.75 (SD, 0.07), 0.70 (SD, 0.08), and 0.70 (SD, 0.06).

CONCLUSIONS

Both kidneys showed similar morphometric parameters by B-mode ultrasound, whereas RI by spectral Doppler decreased progressively from renal artery to interlobar and arcuate arteries.

[Renal failure: diagnostic work-up]

The purpose of this article is to review the diagnostic work-up of renal failure, acute or chronic. The role of the radiologist is to exclude the presence of a curable etiology such as urinary tract obstruction or vascular thrombosis. Renal ultrasound with Doppler imaging is the imaging modality of choice for this indication, and the use of a contrast agent is useful to evaluate renal perfusion. Non-contrast CT remains valuable for the diagnosis of some urinary tract pathologies. Finally, MRI is the most comprehensive imaging modality for the evaluation of the urinary tract, but performed as a second line modality mainly for practical reasons but also due to the non-negligible risk of nephrogenic systemic fibrosis secondary to the intravenous administration of gadolinium based contrast agent.