B-mode and Doppler ultrasound of chronic kidney disease in dogs and cats

Abstract

Ultrasound is the imaging test of choice for renal evaluation, because it provides information about the position, size, shape, internal architecture and hemodynamics of the kidneys without harming the patient. In chronic kidney disease, the main findings observed in B-mode ultrasound images are increased cortical echogenicity, loss of corticomedullary differentiation, reduced renal volume and irregular renal contour, and when these changes are associated, they are indicative of end-stage renal disease. However, the cause of kidney disease cannot be determined by ultrasonography, but must be confirmed by means of biopsy, although the presence of ultrasonographic changes indicative of the end-stage of the disease may contraindicate this procedure. The Doppler ultrasound test complements the ultrasonic B-mode examination and enables the assessment of renal perfusion based on a calculation of the hemodynamic indices, which are increased in cases of chronic kidney lesions, with higher values ​​in the most severe cases. Thus, ultrasound examinations are not only useful in diagnostics but also play an important role in defining the prognosis of patients with chronic kidney disease.

How Ultrasound Can Be Useful for Staging Chronic Kidney Disease in Dogs: Ultrasound Findings in 855 Cases

“…The International Renal Interest Society (IRIS) stages of CKD are based on the evaluation of serum creatinine, symmetric dimethylarginine (SDMA), proteinuria, and blood pressure, in order to facilitate diagnosis, prognostic evaluation, and treatment of the disease [1,3]. Abdominal ultrasonography (US) is routinely performed and recommended in animals with renal disease, or when creatinine serum levels are increased [4][5][6]. Ultrasonography is the first imaging investigation required in both human and veterinary patients with chronic renal failure [4,7].…”

Renal ultrasonographic shear-wave elastography and urinary procollagen type III amino-terminal propeptide in chronic kidney disease dogs

“…In addition, the advanced diagnostic imaging techniques, particularly renal ultrasonographic shear-wave elastography (SWE), have been increasingly performed in humans [ 36 , 37 ]. Increases of both cortical and medullary renal echogenicity detected by B-mode ultrasound are related to the CKD lesions [ 38 ]; these increases may also be present in dogs without evidence of renal impairment [ 39 ]. SWE can evaluate renal parenchyma elasticity or renal tissue stiffness [ 40 , 41 ] by facilitating the Young’s modulus (E) value measurements [ 42 ].…”

Determination of renal blood flow with Doppler ultrasound and the hypertension prevalence and acid-base level in dogs with chronic renal failure

“…Although different RI intervals are specified one by one, the RI value is considered abnormal when it exceeds 0.70 (Novellas et al, 2008 ;Mitchell et al, 1998;Morrow et al, 1996). RI and PI above the upper limit indicate the presence of renal disease (Bragato et al, 2017). The mean intrarenal RI value of healthy dogs was 0.54 ± 0.01 in our study.…”

“…As the first changes in renal diseases begin with the change in blood flow, renal Doppler ultrasonography, which is rarely used in veterinary practice is one of the most important diagnostic tools (Bragato et al, 2017). Previous studies have shown many normal RI values.…”

“…When renal failure occurred, normal balance between vasoconstrictive and vasodilator factors deteriorates in time and intrarenal vasoconstriction occurs. Renal resistive index (RI) and pulsatility index (PI) measurements are used for the calculation of the resistance to tissue perfusion that Introduction occurs in that area (Bragato et al, 2017;Mitchell et al, 1998). They are also used for the determination of the changes in blood flow due to congestion, diuretic effects, acute and chronic renal failure and congenital dysplasia (Novellas et al, 2007).…”