Quantitative Ultrasound of Kidneys, Liver, and Spleen: a Comparison Between Mules and Horses

Abstract

An ultrasonographic evaluation of the renal morphology is subjective in veterinary science. The echogenicity and echotexture are compared among the cortex, medulla, liver, and spleen. The purpose of this study was to quantify the renal echogenicity and echotexture of healthy adult horses and mules. An ultrasonographic examination was performed on 12 horses and 12 mules to obtain bidimensional images of the renal cortex, renal medulla, liver, and spleen. These images were analyzed using a gray-level histogram to obtain the quantitative values of echogenicity, echotexture, and the proportions of each region. Difference between the kidneys of mules and horses was observed. The renal cortex was less echoic (6.59 ± 1.69 less in mules; 3.04 ± 1.03 less in horses) and more homogeneous (0.17 ± 0.24 more in mules; 0.47 ± 0.22 more in horses) than the spleen but more hypoechoic (1.46 ± 0.37 more in mules; 1.05 ± 1.07 more in horses) and homogeneous (0.81 ± 0.11 more in mules; 0.85 ± 0.26 more in horses) than the liver. In comparing the renal cortex to the medulla, it was observed that the renal cortex is more echoic (up to 3.49 ± 1.59 more in mules; 2.07 ± 0.21 more in horses) and heterogeneous (up to 0.45 ± 0.23 more in mules; 0.63 ± 0.09 more in horses). The most important difference between mules and horses was a more hypoechoic and homogeneous renal medulla in mules, indicating a higher water content of the renal medulla in mules than in horses.

Doppler evaluation of renal resistivity index in healthy conscious horses and donkeys

“…conformation, thickness of the skin and subcutaneous tissue, acoustic window) may also have contributed to the technique not working as well with donkeys as in horses. There are inter-specific dissimilarities in subcutaneous fat distribution: compared to horses, donkeys have higher accumulations of adipose tissue in the abdominal wall and other body sites [19]. This poses more technical difficulties in the optimal imaging of the kidney using the transabdominal approach [20], as well as producing higher ultrasound attenuation [19].…”

B-mode ultrasonography and gray scale histogram for evaluation of the nuchal ligament in Quarter horse

“…Most studies involving the GSH Mode and Mean variables have found a similarity between the two (Castiglioni 2018, Fogaça 2018. Nevertheless, the present study found a significant difference between these variables among the groups.…”

“…Ultrasound findings are subjective and produce many discrepancies either due to the ultrasound system variability or to the operator's experience. The GSH can help in diagnostics interpretation and has become an increasingly used tool both in clinical routine and in research (Osawa & Mori 1996, Ferreira & Rasband 2012, Silva et al 2015, Fogaça 2018, Castiglioni et al 2018.…”