Urinary Flashcards
What anatomic regions does the cranial pole of the left kidney contact?
It contacts the greater curvature of the stomach and dorsomedial aspect of the spleen laterally.
Is the spleen dorsal or ventral to the left kidney.
Often ventral
Where is the right kidney found?
In the renal fossa of the right caudate liver lobe
Where do the descending duodenum and right pancreatic lobe lie in relation to the right kidney?
Immediately ventral and medial to it
Describe the anatomy of the renal arteries.
The renal arteries often divide into dorsal and ventral branch before reaching the kidney.
In ~20% of dogs, the renal arteries may be doubles, particularly the left renal artery.
The right renal artery arises before (~2cm cranial) the left renal artery.
Where do the renal veins lie in relation to the renal arteries?
They lie immediately ventral to their corresponding arteries.
What are the three distinct zones that can be seen on ultrasound of the kidneys?
Renal cortex
Renal medulla
Renal sinus - renal hilum opens to the renal sinus
Why is the renal sinus more hyper echoic than the renal cortex?
Because of peripelvic fat - appearing as a v-shaped hyeprehcoic region
What causes increased echogenicity of the renal cortex in cats?
Fat vacuoles in the cortical tubular epithelium
More common in older male cats
For dogs, what is the suggested normal range for kidney length: aortic diameter ratio?
- There is high variation in kidney length of dogs with similar BW. Cats have less variation.
The investigators concluded that a ratio of kidney length to aortic diameter of 5.5. - 9.1 was normal.
<5.5 indicates the kidneys are small
>9.1 indicates the kidneys are large
However, this ratio is rather broad and the usefulness is yet to be established in dogs with various renal disease.
What is range for normal kidney length in cats?
3.0 - 4.5 cm long is considered normal
What are some differentials for renomegaly with smooth contours?
Compensatory hypertrophy Acute renal failure Ethelyen glycosl poisoning Hydronephrosis Acute nephritis Early amyloidosis PSS Diffuse infiltrative disease Diffuse neoplasia
What are some differentials for renomegaly with irregular contours?
Granulomas
Abscess
Polycystic kidney disease
Neoplasia (primary or metastatic)
What are differentials for small kidneys?
Congenital renal hypoplasia or dysplasia
End-stage renal disease
What happens to the kidneys when furosemide or contrast agents are administered?
Diuresis associated with administration of furosemide produces a transient increase in kidney size due to medullary enlargement in normal dogs.
Diuresis associated with water-soluble iodinated contrast agents during urography causes lesser degrees of transient kidney enlargement.
What is the upper limit for renal pelvis, in a normal dog not underlying diuresis?
1.8 mm
Recent studies show up to 3mm in dogs
What is normal thickness of the proximal ureter?
3-4 mm
What does failure to visualize the kidney on an excretory urogram indicate?
Either the kidney is absent from renal genesis or prior nephrectomy
Or it is non-functional
What are the 2 different types of renal cysts?
Simple cyst = round or ovoid contour, echo-free contents, smooth and sharply demarcated thin walls with a distinct far-wall border, and strong distal echo enhancement.
Complicated cysts =
Cysts are frequently seen end-stage kidney disease and might be part of the degenerative process affecting the kidneys. Can also be seen with PCKD.
**Cysts can result in displacement, distortion, and dilation of the collecting system from partial obstruction.
How can you treat a renal cysts?
Solitary renal cyst have been successfully ablated with ultrasound-guided ethanol injection.
What other differentials must be included if the renal cystic walls are thick or irregular, internal separation are present, or the contents of the cysts are not completely anechoic?
Complicated cysts
Hematoma
Abscess
Tumor
What are some differentials for non-neoplastic renal masses with solid patterns?
Granuloma
Hematoma or abscess containing homogenous, viscous internal debris may also occasionally simulate a renal mass
**Fine needle aspiration should be performed
Describe the sonographic appearance of complex renal masses and what each region represents.
Complex masses ay contain a variable mixture of anechoic, hypo echoic and hyper echoic components.
The anechoic and hypo echoic regions represent areas of hemorrhage or necrosis. Sonographers often refer these regions as cystic areas despite the fact that their appearance do not resemble a true cyst. The majority of the mass contains these “cystic” regions.
The solid portions represent a smaller %.
Hyperehcoic areas with dirty shadowing may also occur if gas-producing organs are present.
What are some differentials for complex masses?
Hematomas Granulomas Abscess Acute infarcts Neoplasia (primary or metastatic)
Aspiration for cytologic analysis and bacterial culture may be required for definitive diagnosis.
