Flashcards in Imaging LUT bladder and urethra Deck (25)
Indications for diagnostic imaging of the urethra and urinary bladder
- abnormal urinary profile
- altered urination (dysuria, pollakiuria, haematuria)
- abdo/pelvic trauma
- caudal abdo masses
Which animals need a 3rd view of the LUT?
male dogs - caudal pelvic region to see urethra coursing ventrally
What is seen with urolithiasis?
- Change in opacity
- Dorsal deflection of the colon
4 main types of contrast studies?
- retrograde vagino-urethrogram
- + contrast cystography
- double contrast cystograpy
- - contrast cystography (pneumocystogram) air, CO2, nitrous oxide
Pateitn preparation for LUT contrast studies?
> survey rads for baseline ALWAYS
- colon empty? enema
> Urine sampling before contrast admin (can be bacteriostatic too if trying to culture)
> ± 2-5ml 2% lidocaine (if expanding the bladder)
> contrast media
- Co2 ,N2O (not room air as emboli can form)
- water soluble iodine based contrast media
Outline pneumocystogram process
- foley catheter retrograde -> bladder
- 4-11ml/kg gas
- views obtained (lateral L and R) VD
When is pneumocystogram contraindicated?
Potential ruptured bladder (use + contrast)
Outline process of + contrast study
- 4-11ml/kg water soluble iodine based
- undiluted contrast if rupture suspected
- dilute to 25% conc with saline for other indications
- prefill catheter with contrast medium
> orthogonal views
How can under and over distension be noted?
- wimpy looking deflated balloon
v. - overdistended round shape (loss of pear shape)
(beware can ruptrue/retrograde fill kidneys gas in pelvis)
What is negative contrast study particularly useeful for diagnosing?
> bladder location
- pelvic bladder (sitting on top of pubic bone not hanging over the edge)
- pdf inontinence
- could be herniation
Outline process of double contrast cystogram
- empty bladder
- small volume non-dilute iodine based contrast medium
- add gas (CO2, nitrous oxide) 4-11ml/kg
- reposition patient (ROLL!)
> L and R lateral, VD ± oblique views
What are double contrast cystograms helpful for?
- sit in middle of contrast puddle (gravity dependent)
> blood clots
- not very heavy so swim on top of puddle
- more variable shapes
> air bubbles/mural lesions
- bubbles go towards rim/edges of pelvis on top of puddle
- mural lesions also cause filling defects in same position
- regular v irregular edges (bubble v mass)
What is the positive contrast retrograde vagino-urethrocystogram useful for?
- ± urinary bladder
Procedure of retrograde vagino-urethro-cystogram
- catheter (foley for females with balloon tip)
- 10-15ml (dogs) 5-10ml (cats) water soluble contrast medium
> lateral views when injecting last 2-3mls
- VD not very helpful
What can be seen on + retrograde vagino-urethro-cystogram?
> filling defects
- intraluminal lesion
- mural lesion
- extramural lesion
> extravasation of contrast
> abnormal shape, position or number
How cna you keep the bladder paritally full with a retrograde vaginourethrocystogram?
- prefil contrast/saline
- 25% dilute water soluble iodine based contrast medium (dilute with saline)
- dynamic study (fluoroscpy guided)
- lateral views ± oblique
How do the male and female retrograde urethrocystogram keep contrast in the LUT?
Common causes of incontinence in female dogs?
- strictures in vaginal area
What causes of urethral blockage cause anuria?
- stones (commonly in penile urethra or pelvic flexure)
- bubbles!! (can move by injecting contrast)
> look for filling defect
What types of neoplasia are common in LUT
- tasnitional cell carcinoma
- commonly in trigone
- esp ureterovesicular junction
- can arise from urethra
How would a urethral neoplasia appear?
Abnormal filling defect on retrograde vaginourethrocystogram
How thick shoudl the baldder wall be on ultrasound?
When would thickened bladder wall be seen?
What types of bladder neoplasia occours? What should also be assessed on ultrasound?
- TCC (trigone) most common
> assess medial iliac lymph nodes