Ch. 12 - Contrast Studies

Front 1

What is the purpose of doing contrast studies?

Back 1

To better visualize an organ or organ system from the surrounding soft tissue

(contrast materials appear either very black or very white on films)

Front 2

Contrast studies determine what 5 things of the organ?

Back 2

1. size

2. shape

3. position

4. location

5. function

Front 3

Contrast studies can help to detect defects in the ____________ __________ of the organ.

Back 3

mucosal surface

Front 4

Contrast studies complement....

Back 4

initial rads or survey rads

Front 5

Can contrast studies replace survey rads?

Back 5

NO

Front 6

How do contrast studies demonstrate anatomy?

Back 6

By outlining or filling a cavity / organ

Front 7

Give two examples of organs that contrast studies are demonstrate anatomy for...

Back 7

-stomach

-urinary bladder

Front 8

Contrast studies demonstrate physiology by...

Back 8

being excreted through an organ

Front 9

What organ is an example of contrast studies demonstrating physiology?

Back 9

kidneys

Front 10

Contrast studies can use two types of media: what are they?

Back 10

positive & negative contrast

NEG = LOW atomic # (appear black - ex. air)

POS - HIGH atomic # (appear white - ex. barium sulfate)

Front 11

Contrast material increases contrast in that area. What may need to be increased (adjustment to be made) to give better contrast?

Back 11

kVp

Front 12

What is a pneumocystogram?

Back 12

Air is injected into bladder

(air appears black)

NEGATIVE CONTRAST

Front 13

radiopaque =

radiolucent =

Back 13

white

black

Front 14

Example of giving positive contrast:

Back 14

Barium sulfate to see esophagus and stomach - detect blockages, etc.

Front 15

Give 3 examples of positive contrast media:

Back 15

1. barium sulfate

2. iodine

3. BIPS (barium-impregnated polyurethane spheres)

Front 16

What are the 4 (four) categories of Contrast Materials?

Back 16

1. Positive contrast barium sulfate preps

2. Positive contrast iodinated preps (Ionic & Non-Ionic)

3. Negative contrast gases

4. Double contrast studies

Front 17

Barium Sulfate:

1. Made with elements that have a _______ atomic #.

2. absorbs more X-rays and therefore appears ______.

3. Areas of interest will either appear ___________ or __________.

Back 17

1. high

2. white

3. radiopaque or radiolucent

Front 18

Barium sulfate is used for the ____________.

Back 18

GI tract

Front 19

Contraindications for using barium sulfate?

Back 19

if perforations or ulcerations of GI tract are suspected

Front 20

How can barium sulfate be administered? (two ways)

Back 20

orally / rectally

Front 21

Does barium sulfate alter physiology in any way?

Back 21

NO

Front 22

Barium sulfate comes in what 3 forms?

Back 22

1. powder

2. paste

3. colloid suspension

Front 23

What eventually happens to the ingested barium sulfate?

Back 23

It is excreted in feces

(unless there were perforations - then it leaks into body and will permanently be there unless surgically removed)

Front 24

When using barium sulfate, proper ___________ is required.

Back 24

viscosity

Front 25

If doing an esophageal study, what form of BS should be used?

Back 25

paste

(thicker - stays put longer)

Front 26

What type of BS mixture should you use if doing a colon study?

Back 26

thin mixture

(give rectally)

Front 27

What are 4 disadvantages of using BS?

Back 27

1. takes 3 or more hours to travel from stomach to colon

2. Timed rads are required - this can take hours (to view the movement of the BS through system)

3. harmful to peritoneum

4. should never be given if perforations (anywhere) are suspected

Front 28

If animal has a perforation and BS is given, the BS will leak into body and form a....

Back 28

granulomatous reaction

Front 29

BS can aggravate an already obstructed bowel by....

Back 29

causing impaction

Front 30

When administered per os, care must be taken that...

Back 30

patient does not aspirate BS

Front 31

Dosage for BS in Upper GI Study

________% Barium sulfate

1. dosage for dogs < 10kg + cats

2. dosage for medium-sized dogs, 11 - 40kg

3. dosage for dogs > 40 kg

Back 31

60% BS

1. 8 - 10 ml/kg

2. 5 - 8 ml/kg

3. 3 - 5 ml/kg

Front 32

If doing an upper GI, give BS __________.

If doing a lower GI, give______________.

Back 32

upper = orally

lower = rectally

Front 33

Why should you be careful about mixing BS with food?

Back 33

Animal may have obstruction, in which case you don't want to give them food!

Front 34

Positive Contrast Iodinated Preps

Ionic Iodides

How are they administered? (2 routes)

Back 34

IV or injected into body cavities

Front 35

What happens to Ionic Iodides in the body?

Back 35

They mix with the blood and are excreted by the kidneys within 24 hours

Front 36

Ionic Iodides -

Can they be used for GI tract if perforation is suspected?

Back 36

YES - that's one big advantage -

(in fact they should ONLY be used when perforation is suspected due to their other disadvantages..)

Front 37

Iodine atoms are contrast medium...

the more iodine the __________ the contrast.

Back 37

better

Front 38

Why are ionic iodides ionic?

Back 38

Because each compound is made up of an anion (-) and a cation (+)

Front 39

How long do ionic iodides take to move through the GI system?

Back 39

45 - 60 minutes - FAST!

Front 40

Name one ionic iodide?

Back 40

Gastrografin

Front 41

What are the disadvantages of ionic iodides?

Back 41

1. They are hypertonic and will pull fluids from other areas of the body

2. can increase dehydration

3. rapid bolus can cause nausea, vomiting, and decreased BP (and rarely, cardiac arrest)

Front 42

Contraindications for ionic iodides?

Back 42

myelogram

(irritating to the brain & spinal cord)

Front 43

NON - IONIC IODIDES

(still positive contrast)

These are better tolerated by the body...one reason is because they are closer to being a __________ solution

Back 43

isotonic

(no fluid shift in/out of cells)

Front 44

NON - IONIC IODIDES

Are used for what....?

Back 44

myelograms

Front 45

NON - IONIC IODIDES

Have few adverse effects when injected into...

Back 45

subarachnoid space

Front 46

Can NON - IONIC IODIDES be used intravenously?

Back 46

YES, they can

Front 47

What is the one big disadvantage of NON - IONIC IODIDES?

Back 47

they are 10X more expensive than ionic contrast material

Front 48

NEGATIVE CONTRAST MEDIA:

Have a ________ atomic number and appear ________.

Back 48

LOW

dark, or radiolucent

Front 49

Examples of negative contrast media:

Back 49

gases:

O2, air, CO2

Front 50

Why must you take care if injecting air into a urinary catheter to fill bladder?

Back 50

You could rupture bladder...

Also if bladder has a perforation, you could create an air embolism and kill the animal

Front 51

DOUBLE CONTRAST PROCEDURES

What type of contrast material do they use (negative or positive?)

Back 51

BOTH

Front 52

DOUBLE CONTRAST PROCEDURES

What are the most common organs that we use double contrast media to visualize? (3)

Back 52

1. urinary bladder

2. stomach

3. colon

Front 53

DOUBLE CONTRAST PROCEDURES

Which is administered first: negative or positive?

Back 53

NEGATIVE first

Front 54

Why is it important that negative material be given first?

Back 54

If it's added to positive, it can create air bubbles that can be mis-interpreted as lesions

Front 55

Patient prep...

varies depending on...

Back 55

the study

Front 56

Patient prep

Important thing #1!

With GI studies should patient be fasted?

Back 56

Yes - for 8-12 hours

Front 57

Patient prep...

Important thing #2 (no pun intended!)

With GI studies what else should be done in addition to fasting?

Back 57

enema - want to make sure any remaining gas is gone and that bowels are empty

(do this the morning of...)

Front 58

Patient Prep:

Important thing #3!

Back 58

Fur!

It should not be wet or matted - if it is wet, you need to dry it. If it's matted, you need to comb it out.

Make sure there is no contrast material on animal, in fur, on table, on cassette, etc., or you will have artifacts on your film

Front 59

What effect can sedation have on contrast studies?

Back 59

They typically slow the GI tract down, so they can slow down a contrast study

Front 60

What is one particular drug name and class that decrease GI time?

Back 60

Atropine (an anticholinergic)

Front 61

If giving contrast material by mouth...take care that...

Back 61

animal does not aspirate

(VD views might also be contraindicated due to risk of aspiration...)

Front 62

Name one study where the patient must be anesthetized:

Back 62

pneumocystogram

Front 63

Name 6 Indications for a GI Study:

Back 63

1. vomiting

2. diarrhea

3. constipation

4. melena

5. abdominal mass or pain

6. foreign body ingestion / obstruction

Front 64

what is melena?

Back 64

dark sticky feces containing partly digested blood.

the production of melena, following internal bleeding or the swallowing of blood.