Diagnostic imaging of the Urogenital tract

Question 1

What imaging can be used for urogenital tract?

Answer 1

• Radiography
• Contrast radiography
• Ultrasound

Question 2

What is seen with normal uterus + ovaries on imaging?

Answer 2

• Not visible on radiographs
• US = body between bladder ventrally + descending colon dorsally

Question 3

What is seen with pyometra on imaging?

Answer 3

• Radiography = dilated, soft tissue opacity loops originating between bladder + colon
  -MASS effect
• US = fluid dilation of the uterine horns + body
  -thin/thick cystic wall

Question 4

What is seen with a normal prostate on radiography?

Answer 4

• Caudal to bladder, may be within pelvic canal
• Symmetrical, ovoid to round, urethra centrally
• Homogenous soft tissue opacity

Question 5

What can cause prostatomegaly?

Answer 5

• Benign prostatic hyperplasia - entire dogs, symmetrical enlargement, soft tissue opacity
• Prostatitis - entire, marked enlargement,
  -regular / irregular shape, may see mineralisation +/- loss of serosal detail
• Prostatic neoplasia - castrated, mineralisation, irregular shape +/- loss of serosal detail

Question 6

What are prostatic neoplasias likely to be? Do they metastesise?

Answer 6

• Neutered dogs withs mineralisation = neoplasia
• Carcinoma, TCC
• Metastasis to medial iliac lymph nodes + lumbar vertebrae + Lungs

Question 7

How would you perform cystography?

Answer 7

• Catheterise + empty bladder
• Instill with contrast medium until reasonably distended

Question 8

What can be seen with double contrast cystography?

Answer 8

• Calculi = central defects in contrast pool
• Blood clots = may adhere to bladder wall, often irregular
• Air bubbles = iatrogenic, at pool margins

Question 9

What is done with retrograde urethogram / vaginourethogram?

Answer 9

• Catheterise + empty bladder
• Inflate bladder w air/gas
• Place catheter tip in tip of penis / vulva + clamp
• Inject iodine based contrast + expose at end of injection

Question 10

What is done with intravenous urography?

Answer 10

• IV iodine contrast to see transition through kidneys + ureters into bladder w multiple radiographs
• Need adequate renal function + hydration + fasting + enema

Question 11

When would you use cystography, retrograde urethrogram, IV urogram?

Answer 11

• Cystography = bladder
• Retrograde urethrogram = Urethra (bladder)
• IV urogram = Ureters, Kidneys (refer for CT)

Question 12

What is seen with normal bladder on imaging?

Answer 12

• Radiography = pear-shaped, smoothly marginated, soft-tissue opacity in caudoventral abdomen
• US = pear-shaped organ in caudal abdomen w anechoic content

Question 13

What is seen on imaging with Cystitis (chronic)?

Answer 13

• Radiographs = not visible
• Double contrast cystography = thickened wall, irregular mucosa, blood clots
• US = irregular thickened wall, blood clots

Question 14

What is seen with bladder calculi on imaging?

Answer 14

• Radiography = accumulate in most dependent part of bladder ( centrally)
  -struvite, oxalate, calcium phosphate = marked visibility
  -Silicate = moderate visibility
  -Cystine + urate = non-opaque to faint visibility
• US = strong distal shadowing

Question 15

What dogs are urate seen in ?

Answer 15

• Dalmatians
• Young dogs with PSS

Question 16

What is seen with bladder masses on imaging?

Answer 16

• Radiography = Not visible on plain radiography (effacement)
  -Contrast = defect in contrast pool / soft tissue opacity on pneumocystogram
• Predilection site = trigonium, dorsal bladder wall
• US = Urothelial cell carcinoma (TCC)
  -Sessile, polypoid echoic mass

Question 17

What is seen on imaging with bladder rupture?

Answer 17

• Radiographs = may see loss of serosal detail + small bladder
• Positive contrast = leakage of contrast
• US = Rarely see defect but will see free fluid

Question 18

How would you assess urethra? lesions?

Answer 18

• Retrograde urethrogram
• calculi = defect in contrast medium
• mural lesion = narrowing of contrast medium

Question 19

If you have stranguria what should you do?

Answer 19

• Retrograde urethrogram = problem usually in urethra

Question 20

What is seen with the kidneys on imaging?

Answer 20

• Radiography = retroperitoneal space, L-kidney more caudal
  -bean shaped, sharp + smooth margination
• US = cortex = echoic, similar/ hypoechoic to liver
  -medulla = near anechoic, least echogenicity of all organs
  -renal pelvis + diverticula = hyperechoic, should not contain any urine (anechoic)

Question 21

What can cause unilateral irregular renomegaly?

Answer 21

• Neoplasia
• Cysts
• Abscess, haematoma

Question 22

What can cause bilateral irregular renomegaly?

Answer 22

• Neoplasia/metastasis
• PKD
• FIP

Question 23

What can cause unilateral smooth (generalised) renomegaly?

Answer 23

• Neoplasia
• Hydronephrosis
• Perinephric pseudocyst

Question 24

What can cause bilateral smooth (generalised) renomegaly?

Answer 24

• AKI
• Pyelonephritis
• Lymphoma
• FIP

Question 25

What is seen with pyelectasia + hydronephrosis on US?

Answer 25

• Both show dilation of renal pelvis
• hydronephrosis - more severe dilation

Question 26

What can cause microrenale (small kidneys)?

Answer 26

• CKD
• Dysplasia (congenital)
• Atrophy

Question 27

What is seen with renal cysts on US?

Answer 27

• Renal cysts may be solitary as part of CKD - multiple = polycystic kidney disease
• Thin walled, may distort surface
• Persians predisposed

Question 28

What is seen with ureters on imaging?

Answer 28

• Radiograph = not visible
• US = not visible
• IVU = v useful