Kidneys and ureters Flashcards
In chronic pyelonephritis associated with nephrolithiasis, which ultrasound findings are most characteristic?
A) Hypoechoic renal cortex and well-defined corticomedullary junction
B) Hyperechoic and irregular kidney with distended, deformed pelvis and diverticuli
C) Enlarged kidney with normal pelvic architecture but increased blood flow
D) Hypoechoic foci within the renal parenchyma with decreased pelvic echogenicity
B) Hyperechoic and irregular kidney with distended, deformed pelvis and diverticuli
A dog with ureteral obstruction due to a ureterolith presents with hydronephrosis. Which ultrasonographic feature is most indicative of this condition?
A) Hyperechoic renal cortex with a uniformly small pelvis
B) Hypoechoic, rounded pelvic diverticuli partially separated by hyperechoic septa
C) Hyperechoic renal pelvis with reduced vascular flow on Doppler
D) Markedly hypoechoic renal medulla with hyperattenuating cortical foci
B) Hypoechoic, rounded pelvic diverticuli partially separated by hyperechoic septa
In the case of an infiltrative bladder mass causing ureteral obstruction, what secondary ultrasonographic change is commonly observed?
A) Decreased echogenicity of the bladder wall with normal ureteral diameter
B) Distal ureteral dilation with loss of urine jet visualization on Doppler
C) Increased bladder echogenicity with a hyperechoic renal cortex
D) Normal corticomedullary distinction with reduced renal size
B) Distal ureteral dilation with loss of urine jet visualization on Doppler
What is the primary ultrasonographic feature of an ectopic ureter in a young dog with urinary incontinence?
A) A hypoechoic, thickened bladder wall with a dilated renal pelvis
B) A hypoechoic, fluid-filled tubular structure extending beyond the bladder trigone
C) A hyperechoic mass at the bladder neck obstructing ureteral outflow
D) A normal bladder and kidney but absence of urine jet on Doppler
B) A hypoechoic, fluid-filled tubular structure extending beyond the bladder trigone
In the case of a ureteral rupture, what ultrasonographic findings are most consistent with retroperitoneal urinoma formation?
A) Hypoechoic, poorly defined fluid accumulation adjacent to the kidney
B) Hyperechoic fat with sharply defined fluid pockets in the peritoneal cavity
C) Anechoic fluid collection within the renal cortex
D) Normal renal architecture with increased renal echogenicity
A) Hypoechoic, poorly defined fluid accumulation adjacent to the kidney
Which of the following factors can make imaging the right kidney more difficult in dogs?
A) The presence of gas or feces in the descending colon
B) The presence of intestinal content in the descending duodenum, ascending colon, or cecum
C) The kidney’s proximity to the spleen
D) The use of a high-frequency probe
B
What is the typical length range of a normal cat’s kidney?
A) 3.0 – 4.5 cm
B) 2.0 – 5.5 cm
C) 4.5 – 6.0 cm
D) 2.5 – 3.5 cm
A
The length of a cat’s kidney on a radiograph depends on the cat’s sex, reproductive status, and body weight. https://pmc.ncbi.nlm.nih.gov/articles/PMC11112170/#:~:text=the%20normal%20kidney-,Size,should%20be%20similar%20in%20length.&text=Renal%20size%20varies%20depending%20on,larger%20kidneys%20than%20intact%20cats.&text=Only%20two%20studies%20describe%20cortical,of%200.59%20%C2%B1%200.06%20cm.&text=Park%20et%20al%20recorded%20a,0.07%20for%20the%20right%20kidney.
Sex
Female cats have smaller kidneys than male cats
Reproductive status https://pubmed.ncbi.nlm.nih.gov/10519301/
Neutered cats have larger kidneys than intact cats. Based on this study, normal feline renal length ratios range from 1.9 to 2.6 for neutered cats and 2.1 to 3.2 for intact cats.
Body weight
There is a strong positive correlation between body weight and renal length
Which of the following statements is TRUE about the renal cortex and medulla on ultrasound?
A) The renal cortex is always hyperechoic to the spleen in all cases.
B) The renal medulla appears hyperechoic compared to the cortex.
C) The renal cortex is usually hypoechoic or isoechoic to the liver and typically hypoechoic to the spleen.
D) The renal crest is always hypoechoic.
c
In which of the following cat breeds is the average renal length approximately 3.87 cm?
A) British Shorthair
B) Sphynx
C) Ragdoll
D) Maine Coon
D
What differentiates hydronephrosis from pyelectasia?
a) Hydronephrosis is associated with infection, while pyelectasia is not
b) Pyelectasia is caused only by obstruction, while hydronephrosis is not
c) Hydronephrosis involves obstruction, while pyelectasia does not
d) Pyelectasia always leads to renal failure, while hydronephrosis does not
Hydronephrosis involves obstruction, while pyelectasia does not
Explanation: Hydronephrosis is due to obstruction (e.g., calculus, stricture), whereas pyelectasia can occur due to non-obstructive causes like pyelonephritis or diuresis.
At what pelvic height measurement on transverse ultrasound is outflow obstruction suspected?
a) ≥5mm
b) ≥8mm
c) ≥13mm
d) ≥20mm
A renal pelvic height of ≥13mm suggests an obstruction, although mild cases may have a normal or slightly dilated pelvis.
In the case of leptospirosis in a 2-year-old German shepherd, which of the following is observed in the right kidney?
a) Markedly hypoechoic inner medulla
b) A clear distinction between the cortex and medulla
c) Hyperechoic inner medulla and normal cortex appearance
d) Renal cortex appears thinner than the medulla
C
Which condition is associated with the presence of dystrophic mineralization in the kidney, as seen in a cat with chronic renal insufficiency?
a) Glomerulonephritis
b) Renal lymphoma
c) Chronic interstitial nephritis
C
What is typically seen in the kidneys of animals with protein-losing glomerular diseases, such as glomerulonephritis and renal amyloidosis?
a) Enlarged kidneys with smooth contour
b) Hyperechoic kidneys with reduced size
c) Focal cortical hyperechogenicity
d) Hyperechoic and diffusely enlarged kidneys
D
In the diagnosis of renal lymphoma in cats, which of the following ultrasonographic features is commonly observed?
a) Hypoechoic subcapsular halo and enlargement of the renal sinus
b) A well-circumscribed hyperechoic mass in the renal medulla
c) A large, hyperechoic mass replacing the kidney parenchyma
d) Severe pyelectasia and reduced corticomedullary distinction
A
Which of the following statements is true regarding the influence of the angle of insonation on renal cortex echogenicity?
A) The angle of insonation does not affect the echogenicity of the renal cortex.
B) Renal extremities may appear more echogenic due to the effect of anisotropy, which is influenced by tubule angulation.
C) Anisotropy causes the renal cortex to always appear darker on ultrasound.
D) Spatial compounding imaging increases the effect of anisotropy on renal echogenicity.
B
Explanation: The echogenicity of the kidney cortex can vary based on the angle of the ultrasound waves and the orientation of the kidney’s tubules.
Anisotropy (efers to the directional dependence of a material’s properties, in this case, how a tissue reflects ultrasound waves. Essentially, anisotropy in ultrasound happens when the tissue’s response to sound waves varies depending on the angle at which those waves hit the tissue), or the varying reflection of sound waves based on the angle, can make the renal cortex appear more echogenic at certain points, especially at the edges of the kidney.
Ruth et al. 2013 refers to a study that likely explored this effect, showing how spatial compounding imaging can help improve the accuracy of ultrasound images, especially when assessing areas like the renal cortex. Spatial compounding is a technique where multiple ultrasound images are taken from different angles, and the computer combines them into one clearer image.
In a dog with acute tubular necrosis due to ethylene glycol toxicity, which feature is most likely to be observed on ultrasound?
A) Hypoechoic cortex and medulla
B) Hyperechoic cortex with enhanced corticomedullary distinction
C) Normal corticomedullary distinction with mild renal enlargement
D) A prominent hypoechoic rim sign in the outer medulla
b
What is a significant ultrasound feature observed in cats with chronic interstitial nephritis?
A) Small, rounded kidneys with irregular margins and radiating hyperechoic striations
B) Hypoechoic renal cortex with clear corticomedullary distinction
C) Large kidneys with multiple anechoic cysts and increased renal pelvic height
D) Renal enlargement and decreased echogenicity of the cortical layer
a
Which of the following conditions is characterized by the presence of a “medullary rim sign” in the kidneys?
A) Juvenile nephropathy
B) Leptospirosis
C) Ethylene glycol toxicity
D) Renal agenesis
c
In the case of renal dysplasia in dogs, which of the following sonographic features is likely to be observed?
A) Uniform cortical hyperechogenicity without loss of corticomedullary distinction
B) Hyperechoic or speckled medulla with loss of corticomedullary distinction
C) Enlarged kidneys with well-demarcated corticomedullary boundaries
D) Presence of anechoic cysts in the renal cortex
b
