Contrast Radiography - Urinary
Card Set Information
Contrast Radiography - Urinary
Clinical Practice ll
Clinical Practice ll
What is a IVP?
contrast radiology to evaluate the kidneys and ureters
What are we evaluating with the ureters when doing a contrast study?
What are we evaluating with the kidneys when doing a contrast study?
What is involved in a urinary tract contrast study?
What does IVP stand for?
What is the size of a dog kidney? Cat?
: 2.5 - 3.5 times the size (length of the 2nd lumbar vertebra
: 2.5 - 3 times the size of the 2nd lumbar vertebra
What is the shape of a dog, cat, horse, and cow kidney?
dog and cat
: typical "kidney bean" shape with smooth borders
: right kidney "valentine heart" shaped
Can an IVP test for renal function?
What are the factors that affect the kidney's ability to concentrate urine?
dose of contrast agent
rate of administration
route of administration
What is renal failure?
How do we administer the contrast agent to test for kidney function? Why can't we administer it any other way?
it will be irritating and it will not pick up the agent fast enough to opacify the kidneys
What type of lesions can be detected with IVP?
When do we do an IVP?
abnormal urine (blood, crystals, pyuria, tumor cell)
abnormal size, shape of kidneys on palpation
trauma to urinary system
suspected kidney stone
masses involving the kidney
Are kidney stones common in dogs and cats?
What are some precautions for IVP? And how do we prevent them?
: rehydrate, keep on fluids
: increase dose, maintain hydration
What contrast agents do we use for IVP?
iodinated (diatrizoate, iothalamate compounds)
How much iodine do we administer for IVP? What is the maximum we can give? How do we administer it?
300 - 400 mg iodine/ml
maximum 90 ml
administer rapidly IV catheter over 1 - 3 minutes
For renal failure patients, if BUN > 50 mg/dl or creatinine is > 4 mg/dl how much iodine do we administer?
give 1700 mg iodine/kg
How do we prep a patient for IVP?
fast for 12 - 18 hours
limit fluid intake 12 hours before IVP
empty bladder before study
place IV catheter
survey radiographs (VD and lateral)
inject contrast agent
Do we usually use anethesia for IVP?
How do we take the images for an IVP?
1, 3, 5, 15, 20, 40 minutes
What can we apply around the wait directly cranial to the hip for an IVP?
What is the purpose of a compression bandage?
compress distal ureters
cause filling of kidney - renal pelvis and collecting tubules
prevent filling of bladder
with bandage on, ureters are 2 - 3 times actual size
What are the phases of IVP?
What is the arteriogram?
demonstrates renal blood flow
What is nephrogram?
contrast agent is evenly perfused throughout the kidney
used to evaluate renal parenchyma
What is pyelogram?
evaluates renal collecting system, including renal pelvis and ureters
What is cystogram
drainage into bladder
does not distend bladder
can examine junction of ureters and bladder
Is a cystogram suitable for evaluating the bladder?
What is ectopic ureter evaluation?
see where ureters are connecting bladder, neck, urethera
How do we do an ectopic ureter evaluation?
drain bladder of urine, inflate with gas
see entire ureter length
What is a cystography?
contrast study of bladder by retrograde injection of contrast material
When was cystography most commonly used?
before we had ultrasound
What does a cystography evaluate?
size, shape, location of bladder
thickness of bladder wall
contents of bladder (stones, masses)
When do we do a cystography?
abnormal urine (blood, crystals, segs)
abnormal urination (dysuria, obstruction, incontinence, straining, increased frequency)
abdominal masses in area of bladder
suspected urinary calculi not visible on survey view
determining location of bladder
When should we NOT do a cystography?
severe bladder disease
cystocentesis - not within 24 hours - may force fluid through hole
What kind of contrast agent do we use for a cystography?
water soluble iodine compounds
How do we prep the patient for a cystography?
same as for an upper GI contrast study
Do we need to use anethesia for cystography?
What are the steps of cystography?
survey films (VD, lateral, oblique)
if blood clots are present, flush with steril saline to remove
infuse lidocaine into bladder
infuse contrast agent
How do we do a urinary catherter for cystography?
aspetic technique - mild scrub, sterile lube, 3-way valve
remove air from catheter
fill with contrast agent before insertion - prevent air bubbles
Why do we infuse the bladder with lidocaine for cystography?
to reduce spasticity which prevents complete distension of the bladder
What is the goal when administering a contrast agent for cystography?
to fully distend the bladder
How do we monitor infusion during cystography?
amount of back pressure on syringe
never force into non-distensible bladder
What kind of radiographs do we need of cystography?
right and left obliques
What do we need to avoid when we are taking radiographs for cystography?
superimposition of hip bones
Why do we do a double contrast cystography?
shows mucosal detail and masses in lumen
What do we usually do first in cystography, positive contrast or double contrast?
How do we do a double contrast cystogram?
infuse 10 - 30 ml of undiluted positive contrast agent to coat mucosa well
massage bladder and rotate patient to distribute
remove undiluted agent
infuse gas into bladder
monitor infusion - palpation, back pressure
What is a negative contrast cystogram?
simple infusion of gas into the bladder
Does a negative contrast cystogram give us more information than a positive contrast cystogram?
no, gives us less information
How much do we need to reduce the kVp when doing a negative contrast cystogram?
by 4 - 6
Can we do a negative or double contrast study if the bladder is ruptured or there is active bleeding suspected? What could happen if we did?
air embolism is possible
What can we use instead of room air to do a cystography? Why?
CO2 or N2O
20 times more soluble in blood than air, bubbles dissolve rapidly
When should we do cultures and sensitivity tests for the bladder?
before doing a cystograph
What does urethrography evaluate?
distal portion of urinary tract by retrograde infusion of contrast material
Is a urethrograph usually done in males or females?
What does a urethrograph look for?
When would we do a urethrograph?
prostate problems in male dogs
suspected rupture of the urethra
Waht kind of contrast agent do we use for a urethrograph?
positive - iodine
How do we mix iodine for a urethrograph?
dilute to 200 mg iodine/ml with sterile saline
can mix iodine with K-Y jelly half and half
Why do we mix iodine with KY jelly for a urethrograph?
gives good mucosal detail
good identification of small calculi
How do we prep patient for a urethrograph?
same as for an upper GI
fasting, cathartic, enema
Can we anesthestize the patient for an urethrograph? Why would you use anesthesia?
yes it's usually needed
uncomfortable to pass catheter, fill bladder
When do we take the radiograph for a urethrograph?
take x-ray as finishing the injection to fully distend urethra
How do we catheterize for a urethrograph?
same as for cystogram
use largest size catheter as possible
balloon tip is better
remove air bubbles before insertion
What might we find when we pass a catheter for a urethrograph?
may find stones in the urethra
Where does the tip of the catheter go for an urethrograph?
place tip of catheter just inside the urethral orifice
Which radiograph views do we take for a urethrograph?
How do we position the animal for an urethrograph?
position rear legs out of the way
pull cranial to look at distal urethra
pull caudal to look at prostatic urethra
Describe the technique for a voiding urethrogram.
done after positive contrast cystogram
bladder full of contrast material is expressed with a paddle
radiograph is made when urine is seen at tip of urethra
When should we not do a voiding urethrogram?
if the bladder is badly diseased and may rupture
Describe the technique for a prostatic urethrogram.
patient prep (the same as other urinary tract studies) except leave bladder half full or urine or saline
insert catheter so that the tip in in bladder lumen
aspirate while slowly pulling catheter out
when urine flow stops, the tip of the catheter is just within the urethra
pull catheter back another 1 - 3 cm
inject contrast agent as for retrograde urethrogram
take radiograph during injection
Which radiograph views do we do for a prostatic urethrogram?
lateral and obliques
What does a prostatic urethrogram look for?
prostatic fistula communicating with the urethra