Test 2: lecture 8

Question 1

types of contrast studies

Answer 1

Question 2

___ are a type of positive contrast

Answer 2

barium and iodine

Question 3

___ are a type of negative contrast

Answer 3

room air

CO2

Question 4

___ is a type of double contrast

Answer 4

barium and gas

iodine and gas

Question 5

pneumocystogram

Answer 5

place urinary catheter

remove urine, place air

Question 6

where can you use negative contrast?

Answer 6

put air in area to make wall thickness apparent and outline hollow organs

bladder: pneumocystogram

colon: pneumocolon

stomach: pneumogastrogram

Question 7

advantages, disadvantages and risks of negative contrast

Answer 7

add air to area

Advantages:
¨ Always available, cheap

Disadvantages:
¨ Limited info

Risks:
¨ Over distention and rupture
¨ Air embolism (= obstruction of a blood vessel caused by the entrance of air into the bloodstream). (CO 2 better soluble à risk ↓↓)

Question 8

positive contrast is used for

Answer 8

(add high atomic number substance→ radiopaque → white)

Outlining of internal surface of hollow organs, vessels
and ducts

Organ location and size

Wall thickness

Filling defects

Viscus rupture

Question 9

intraluminal filling defect

Answer 9

positive contrast

calculus, blood clot, FB, gas bubble

Question 10

intramural filling defect

Answer 10

positive contrast

arising from the wall (mass-neoplasia, abscess granuloma, polyp) even if occupies the entire lumen!

Question 11

extraluminal filling defect

Answer 11

seen in positive contrast study

a lesion outside the images organ, compressing/displacing it

Question 12

what kind of positive contrast can only be used in the GI tract

Answer 12

barium

Question 13

What positive contrast can be used for transit and emptying times of the GI tract

Answer 13

barium

Question 14

advantages of barium

Answer 14

positive contrast

Relatively cheap
¨ Relatively tasty
¨ Good mucosal coating (imaging, curative?)
¨ Non-toxic, No side effects (intraluminal)
¨ If aspirated- usually benign (from bronchi-expectorated. From alveoli- phagocytosed and transported to tracheobronchial ln)

Question 15

disadvantages of barium

Answer 15

Can only be used in the GI tract (+ airways).
¨ Leakage into mediastinum or peritoneum →inflammation, fibrosis and granuloma formation. Surgical emergency. → DO NOT USE IF GI RUPTURE IS SUSPECTED!
¨ Should not be used pre- or post endoscopy ( pre- blocks vision, post- risk of leakage↑)

Question 16

if GI perforation is suspected or pre endoscopy what positive contrast should be used

Answer 16

iodinated medium

Question 17

esophagram

Answer 17

give barium or iodine to look at esophagus

Question 18

when to use barium enema

Answer 18

tell the difference between small and large bowel loops

masses, strictures, ect

Question 19

ionic iodinated contrast

Answer 19

Dissociate into anions and cations → hyperosmolar.

Side effects (mainly due to hyperosmolarity)

Cost ↓

Question 20

non-ionic iodinated contrast

Answer 20

Do not dissociate into anions and cations → hypoosmolar.

Side effects much less severe and less common.

Cost ↑

Question 21

in the GI tract what happens to ionic iodinated contrast

Answer 21

ionic → hyperosmolar, this means fluids will be drawn in → dilutes the contrast and decreases image quality

Question 22

where can you not use ionic iodinated contrast media

Answer 22

intrathecal injection (myelogram) → spinal cord

Question 23

where can you use iodinated contrast

Answer 23

you can use it almost anywhere

Question 24

intravenous urogram

Answer 24

inject iodine into the veins, this will travel to the kidneys to be excreted

makes kidneys easier to see

Question 25

for viscus rupture what kind of contrast is recommended

Answer 25

**Positive Iodinated Contrast Medium** **Positive:** largest contrast with normal body opacities (negative- same as gas in lungs or GI). **Iodinated**: can't use barium in peritoneal cavity or mediastinum → inflammation. **Preferably non-ionic:** ionic medium pulls more fluid (hyperosmolar).

Question 26

when to use double contrast

Answer 26

gas and barium gas and iodine used most commonly in the **bladder**

Question 27

what is the advantage of double contrast

Answer 27

can see very small detects because the gas provides a dark background

Question 28

Examples of intra-luminal filling defects are… Abscess, sludge Blood clots, polyps Granulomas, air Bladder calculi, gas bubbles Neoplasia, foreign body

Answer 28

Bladder calculi, gas bubbles

Question 29

In a colonogram, when the colon does not fill up well with contrast medium due to an enlarged prostate, this is an example of an… Intra-mural filling defect Intra-luminal filling defect Extra-ordinary filling defect Not enough information provided to determine nature of filling defect Extra-luminal filling defect

Answer 29

Extra-luminal filling defect

Question 30

For which of the following studies barium should NOT be used? Bronchogram Colonogram Retrograde vaginogram Esophagram Gastrogram

Answer 30

Retrograde vaginogram

Question 31

A pyelogram is a sensitive study to rule out… Vascular anomaly Urethral obstruction Urinary bladder calculi Ureteral obstruction Urinary bladder tear

Answer 31

Ureteral obstruction

Question 32

An appropriate choice of contrast media for a double contrast cystogram would be… Ionic and non-ionic iodine Barium and iodine Iodine and saline Iodine and CO2 Barium and room air

Answer 32

Iodine and CO2

Question 33

In a colonogram, when the colon does not fill up well with contrast medium due to an enlarged prostate, this is an example of an… Not enough information provided to determine nature of filling defect Extra-ordinary filling defect Intra-luminal filling defect Intra-mural filling defect Extra-luminal filling defect

Answer 33

Extra-luminal filling defect

Question 34

For which of the following studies barium should NOT be used? Esophagram Gastrogram Bronchogram Colonogram Retrograde vaginogram

Answer 34

Retrograde vaginogram

Question 35

Which of the following may be a reason to choose iodine over barium? Minimizing side effects in a hypovolemic patient Expecting endoscopy may be required after the contrast study Financial concerns Wanting to optimize mucosal coating Suspecting urinary bladder ulcerations

Answer 35

Expecting endoscopy may be required after the contrast study

Question 36

Using an ionic iodinated contrast medium may… Be recommended for a patient with heart disease Be the first choice for an esophagram in most patients Be a safer choice for an unstable patient Be used for a myelogram Result in poorer image quality in the GI tract

Answer 36

Result in poorer image quality in the GI tract

Question 37

A pyelogram is a sensitive study to rule out… Ureteral obstruction Urinary bladder tear Urethral obstruction Urinary bladder calculi Vascular anomaly

Answer 37

Ureteral obstruction

Question 38

A cat is vomiting and possibly ingested a small ball last night. You would recommend to perform a ___ using \_\_\_

Answer 38

upper GI contrast study barium (could use iodinated agent if the ball is still in the stomach and endoscopy for removal is considered after the contrast study..)

Question 39

A dog presents with regurgitations. On plain radiographs, there is evidence of pneumomediastinum (=free air in mediastinum). To rule out esophageal perforation, you would perform a ___ using \_\_\_

Answer 39

positive contrast esophagram non-ionic iodinated