Urogenital System Imaging 1

sihirlifil's version from 2017-11-28 17:14

Bladder Ultrasound

Question Answer
Indications of bladder USHematuria
Follow-up of UTI
Abnormal findings on radiography
Assessment of location, lumen, wall thickness, contents
US-guided sampling
Technique of bladder USDorsal or lateral recumbency, or standing (sediment bladder content)
Curvilinear & linear transducers, 5-10MHz
Doppler function is useful when assessing ureters
Clip, clean, US gel
Longitudinal & transverse image planes, include assessment of uterus/prostate & sublumbar LN
How does normal bladder look on US?Moderate distention
When empty, bladder wall is thicker (<5mm) than when full (1-2mm)
Wall layers visible, but less than SI
Assessment criteria for bladder USSize
Luminal content
Wall thickness, visible layering, mucosal outline
Mural a/o luminal masses
ID of other abdominal organs/extrinsic lesions displacing bladder wall & regional LN
Difference between these 2 US?
Left = Canine (more pear-shaped, gradually narrows towards bladder neck)
Right: feline (oval, even diameter at neck)
Mineralized sediment/small uroliths create acoustic shadowing
Unlabeled yellow arrows pointing to?
Acoustic shadow cast by large urolith in bladder lumen (hyperechoic)
How does crysalluria look on US?Hyperechoic sediment in bladder
Acoustic shadowing due to mineralized crystal accum (settles due to gravity)
What else can you do to assess crystalluria on US?Stir when moving the bladder!
Chronic cystitis
How does chronic cystitis look on US?Thickened wall, uneven mucosa, wall layering +/- visible
Changes mainly in the apex (whole bladder if severe)
Often echogenic urine
Gas inclusions in emphysematous cystitis
Dx of cystitisCystocentesis & UA
Polypoid cystitis
What is polypoid cystitis?Formation of pedunculated wall associated lesions
Sequel of chronic inflam changes
Bladder wall tumor
How does bladder wall neoplasia look on US?Wall-associated, broad-based, wall layering lost
Can't be moved when agitating bladder or moving animal
Usually in TRIGONE
What does TCC look like on US? (other types?)Rough surface, cauliflower-like (also have leiomyoSA, fibroSA, lymphoma)
Bottom: cushion-like projections/thickening of bladder wall = TCC
right = bladder lumen, can contact-spread to opposite wall
INDENTION OF BLADDER BY SMALL INTESTINES! Adjacent structures may indent if not very full
What do you do to ddx wall thickening from mass (tumor vs cystitis vs blood clot)?
Change patient position!
Tumor remains in situ
Cystitis: mainly apical wall thickened
Blood clot generally moves to dependent part of bladder
Label dis
a: Vertex/apex
b: Bladder
c: Trigone
d: Prostate
e: Colon
Red arrows = Urethra
Os penis not depicted but visible on rads
Technique for L view of male canine urethra?R lateral recumbency, pull HL cranially & hold in position with sandbags (and tail)
Center 1ry beam on ischium, collimage for cd abdomen & pelvis
Low kV/high mAs = high contrast, better visual of calculi
How does the urethra look on radiographs?Proximal: not visible (maybe in animals with sufficient retroperitoneal fat)
Obstruction is possible even when no stones visible!
Large bladder & stranguria: suspicion of urethral obstruction
Look for loss of detail at bladder neck (leakage)
Bladder neck/urethra: Cat’s bladder is severely overdistended
Where does the urethra begin in males? Females?Males: cranial border of prostate
Females: Pelvic rim
Indications for retrograde contrast studies of the urethraSuspicion of rupture, stricture, obstruction
Congenital anomalies
Urinary incontinence
Dysuria, Stranguria, pollakiuria, hematuria
On this normal retrograde urethography in a male dog: arrow in left image? The right image is oblique VD so which 2 structures (a & b) don’t superimpose?
Left: small amount of prostatic reflux into prostatic ductules is normal, prostatic part of urethra may be wide (bottom yellow = os penis)
Right: a = prostatic urethra, b = penile
This retrograde vaginourethrography (canine) shows which normal structures?
Top left: Cervix
2: Vagina
3: Vestibulum
4: Foley catheter balloon
6: bladder
Keep in mind when doing retrograde vaginourethrography in a dog:Don’t overfill vagina! may lead to rupture. Don’t introduce balloon too deep (occludes distal urethral opening)
In the normal male cat, the narrowest part of the urethra isDistal & penile
In the female cat, the vagina lies ___ to the urethraDorsal
Causes of filling defects in the urethra of a male dogUrethral uroliths
Gas bubbles
(blood clots)
Common localization of obstruction in male dog urethraBase of os penis
Ischiadic arch
Catheter in tip of penis pre-filled with CM
Os penis
Filling defects
These 2 images show?
Top is plain radiograph showing mineral opacities at lvl of base of os penis
Bottom: Retrograde urethrography showing air bubbles (minimize by pre-filling extension tube with contrast)
What parts of the urethra can be imaged via US?Male: Prostatic urethra
Female: proximal
Distal: between ischium & penis w/ linear high frequency transducer (wall & lumen)
How does grit/small urolith accumulation look on US?Longitudinal at base of os penis: hyperechoic irregular luminal filling, acoustic shadowing (between calipers)
Causes of urethral ruptureTraumatic: 2ry to pelvic frax, iatrogenic (forceful catheterization, bladder expression), direct trauma
Perforating neoplasia, erosion, ulceration
Radiological findings of urethral ruptureBladder may be full, cranially displaced w/ complete rupture/avulsion
Extravasation of CM at site of rupture in contrast urethrography
Pelvic fracture & urethral rupture (retrograde urethrography)
Extravasation of CM at lvl of pelvic urethra
**Always take plain radiographs first!! Need to assess fracture, and contrast stays in for a while


Recent badges