Small animal special procedures

Question 1

Special procedures indicated for

Answer 1

Special procedures supplement or confirm information gathered from routine survey radiographs
Soft tissue structures or organs can be difficult or impossible to identify on regular films due to lack of contrast

Question 2

Contrast media is administered to

Answer 2

Increase radiographic contrast within an organ or system
Visualize structures for size, shape and position
Identify defects in mucosal surfaces or luminal contents
Evaluate organ function or assess the physiological condition of that organ

Question 3

Choice of contrast media is made by

Answer 3

Type of study
Condition of patient
Possibility of side effects

Question 4

Positive contrast agent type

Answer 4

Barium or iodine

Question 5

Positive contrast agents work by

Answer 5

Have components of high atomic number so absorb more x-rays than soft tissue or bone
This high absorption causes them to appear white on radiograph
Used to fill or outline a hollow organ
Can be injected into blood vessels**

Question 6

Negative contrast agents are

Answer 6

Consists of air, oxygen, carbon dioxide and nitrous oxide

Question 7

Negative contrast agents looks like

Answer 7

Low specific gravity so more radiolucent than soft tissue
This causes them to appear black on radiograph
Enhances contrast between various soft tissues
Produces less mucosal detail than positive media

Question 8

Barium sulfate is

Answer 8

White powder, colloid suspension or paste
Given orally or rectally

Question 9

Contraindications for barium

Answer 9

Media of choice for gastrointestinal studies as it is completely insoluble
Will not be diluted by alimentary secretions
Not absorbed through intestines

Question 10

Disadvantage of barium

Answer 10

Because barium does not absorb or breakdown, if GI tract has perforation the barium can pass through the perforation into thoracic or abdominal cavity and remain there indefinitely
If perforation is suspected use soluble iodine first
Able to be quickly absorbed by the body
If iodine study is negative, can then follow up with barium series
There is also the possibility of granulomatous reaction

Question 11

Barium impregnated polyethylene spheres (BIPS are

Answer 11

Used for evaluation of gut motility and transmit time
Two sizes
5 mm and 1.5 mm
Patients given 10 large spheres and 30 small spheres
Must follow manufacturer guidelines closely
Frequency of x-rays determined by tentative diagnosis

Question 12

Iodine preperations

Answer 12

Generally used for intravascular or injected into body cavities
Water soluble
Rapidly excreted by kidneys
Most of the media is out of the body in 24 hours

Question 13

Two types of iodine

Answer 13

Ionic and non-ionic

Question 14

Ionic iodine characteristics

Answer 14

3 iodine atoms to 2 particles in the solution
Also known as high-osmolar contrast agents
HIgher risk

Question 15

Non-ionic iodine characteristics

Answer 15

3 iodine atoms to 1 particle in the solution
Also known as low-osmolar contrast agents
Close to being isotonic, so reduced risk
Is more viscous and more expensive

Question 16

Double contrast studies is and benefits

Answer 16

Use both positive and negative medias
Benefit:
-Optimum mucosal detail without masking small anomalies

Question 17

Patient preparation for contrast studies

Answer 17

Vital to diagnostic radiographs
Withhold food for 12 hours prior to study to ensure GIT empty
Food in GIT can obscure/hide areas of interest
Enema can be given minimum of 4 hours prior to procedure
Sedation or anesthesia may be required for some procedures
Be aware of contraindications!
Make sure hair coat is clean, dry and free from debris/mats
Make sure no contrast media on patient, x-ray table, or cassettes
Remove collars and harnesses

Question 18

Why do you take survey radiographs

Answer 18

Ensures patient is suitable for the study
GIT clean, no causative agents seen without aid of contrast
Ensure technique selection is appropriate
Prevents any waste of time of money

Question 19

Types of special procedures

Answer 19

Esophagram
Upper GI Study*
Lower GI Study*
Retrograde Cystography
Excretory Urography
Pneumocystogram/Cystography*
Urethrography
Myelography

Question 20

Upper GI study is preformed when and indicated when

Answer 20

Performed to evaluate stomach and small intestines
Indications:
Recurrent unresponsive vomiting
Diarrhea
Hematemisis
Melena
Abnormal bowel movements
Foreign body or obstruction
Chronic weight loss
Persistent abdominal pain

Question 21

Procedure for barium studies

Answer 21

Barium administered orally per os via stomach tube
Contraindicated if perforations suspected – use caution
Can be replaced with endoscopy or ultrasonography
Make sure to give the complete volume for proper distention

Question 22

When to take images in barium abdominal series

Answer 22

Immediate films:
VD, DV, left and right lateral
May oblique 15 degrees to right to view pyloric sphincter
At 15, 30, and 60 minutes
VD* and right lateral
Every hour after
VD and right lateral until barium is all in the colon
May also require a 24 hour radiograph

Question 23

Lower GI barium enema indications

Answer 23

Performed to evaluate cecum, colon and rectum
Indications:
Abnormal bowel movements characterized by:
Excessive mucus
Bright red blood in feces
Painful defecation
High frequency diarrhea
Also used to detect:
Intussusceptions
Rectal mass
Abdominal mass
Stricture
Colonic obstruction
Commonly replaced by endoscopy

Question 24

Lower Gi study patient preparation for barium enema

Answer 24

Animal fasted 24-36 hours (allowed water until 4 hours prior)
Make sure patient properly hydrated, increased risk if dehydrated
Perform enema 4 hours prior to procedure
Use sedation or anesthesia
Avoid narcotics
Contraindication: bowel perforations (as per UGI study)
Use contrast media at room temperature or slightly warmer

Question 25

Lower GI procedure for barium enema

Answer 25

Patient in lateral recumbence Insert lubricated Foley catheter tip into rectum and inflate balloon Should be located just inside internal anal sphincter Attach catheter to infusion bag or syringe Infusion bag only needs to be slightly higher than patient Slowly infuse barium until have reached desired distension

Question 26

Radiographs needed for lower GI barium series

Answer 26

VD, right and left lateral Oblique if necessary* - removes portions of colon away from lumbar spine and os penis Evacuate the colon VD and lateral post evacuation may be required Double contrast can also be performed at this time by adding air to colon once evacuated Remove catheter

Question 27

Contrast study of the urinary system is for and indicated when

Answer 27

Evaluates kidneys, ureters, bladder, urethra, and prostate Indications: Hematuria Proteinuria Crystalluria Polyuria Isosthenuria Dysuria Pyuria Etc....

Question 28

Do you use barium in the urinary tract

Answer 28

NO NEVER USE BARIUM

Question 29

What has replaced contrast studies in urinary

Answer 29

Ultrasound

Question 30

Cystography is

Answer 30

Introduction of contrast into bladder via urinary catheter Positive, negative or double contrast studies can be used Sedation recommended

Question 31

Precautions for cytography

Answer 31

Leakage of iodine around catheter giving contrast artifacts Do not over distend bladder Must maintain aseptic technique

Question 32

Patient preparation for cystography

Answer 32

No food for 24 hours, water ad libitum Enema the night before or at LEAST 4 hours prior Obtain urine samples for lab BEFORE injection of contrast media Dehydration must be corrected before procedure Empty bladder before injecting contrast media

Question 33

Cystography procedure

Answer 33

Insert lubricated catheter using sterile technique Introduce contrast media For double contrast study: After introduction of positive contrast roll patient side to side then introduce the negative contrast

Question 34

Radiographs required for cytography

Answer 34

Survey radiographs VD and right lateral After injection of contrast media VD, left and right lateral May require oblique VD to move bladder off lower lumbar spine Especially for males with prostate or urethral issues

Question 35

Excretory urography is and how to do

Answer 35

Used to be called IVP or IVU Intravenous pyelogram/urogram Intravenous injection of water soluble iodine to evaluate kidney structure and collection system Patient preparation is the same as cystography Inject warmed contrast media within two minutes Flush IV catheter with heparinized saline

Question 36

Excretory urography required radiographs

Answer 36

Immediately take VD At 5 minutes take VD and right lateral If evidence of contrast in kidneys may apply compression At 15 – 20 minutes take VD and right lateral If compression was applied, now remove it At 30 – 40 minutes take right lateral and VD oblique

Question 37

Urethrography is

Answer 37

Sedation is required Consists of filling the urethra with contrast media Precautions as per cystogram

Question 38

Urethrography used to detect

Answer 38

Urethral trauma Stricture Obstruction Tumors Etc...

Question 39

Urethrography required views

Answer 39

Lateral view as contrast is being infused into urethra VD or oblique if needed

Question 40

Fistulography is

Answer 40

Injection of positive or negative contrast into a fistula to determine extent of tract Water soluble iodine is used with a Foley catheter Contrast is infused into fistulous tract until just begins to leak past the catheter

Question 41

Fistulography required views

Answer 41

Required radiographs: Lateral and VD/CC/DP May require films 3-4 min post injection

Question 42

Myelography is

Answer 42

Introduction of positive contrast into subarachnoid space of spine via a spinal needle Replaced by Computer Tomography (CT) or Magnetic Resonance Imaging (MRI)

Question 43

Myelography is indicated

Answer 43

Indicated to highlight lesions within the spinal column such as: Compressions Masses Protruding discs Vertebral abnormalities Spinal cord swelling

Question 44

Procedure for myelography

Answer 44

General anesthesia require Site of injection is surgically prepared Spinal needle inserted Any spinal fluid required for diagnostic testing is now taken Slow injection of positive iodine preparation into subarachnoid space of spinal cord

Question 45

Radiographs needed for myelography

Answer 45

Lateral and VD at site of suspected lesion

Question 46

Contrast agents for other modalities

Answer 46

Computed tomography uses non-ionic contrast agents MRI will use chelated gadolinium that is injected IV to differentiate one tissue from another Scintigraphy or Nuclear Imaging uses radioactive contrast agents