Contrast Media + Appropriateness to Exam

What are characteristics of radiolucent (negative) contrast media?

Has a low atomic number

What are characteristics of radiopaque contrast media?

• results in greater attenuation of x-ray photons

• examples include barium and iodine-based iodinated media

• higher atomic number

Negative contrast media are rarely used alone as a contrast agent due to?

Rapid body absorption 

What are some examples of positive contrast media?

• barium sulfate

• oil-based iodine contrast

• water-soluble iodine contrast 

What is true regarding barium sulfate and patient care?

• a perforated GI tract may cause the barium to leak outside the bowel and may cause peritonitis 

• patients should be instructed to drink plenty of water following an exam with barium sulfate 

• provides greater delineation of mucosal detail and is more resistant to dilution than iodinated agents 

Sedated patients should not undergo and UGI exam because the swallowing reflux is reduced which can result in an increased risk of aspiration

True 

What is true regarding oil-based contrast media?

• they are insoluble in water

• they are not readily absorbed by the body 

• can be used for myelograms, bronchography, dacrycocystrography (tear ducts) and salivary glands 

Osmoality

Measurement of the total number of particles in the solution per kilogram of water 

Most adverse reactions occur with ionic iodine contrast media upon injection because the cation dissociated from the parent compound causes an increase in osmolality of the blood plasma 

True 

The glomerular filtration rate (GFR) is the best test to measure your level of kidney function and may also determine a patients stage of kidney disease 

True 

Normal creatine ranges are approximately 0.5-1.2 mg/dL

True 

What may be used to reduce the viscosity of non-ionic contrast media and help ease of injection?

Place in warmer 

What ranges are considered normal for blood urea nitrogen (BUN)?

7-20 mg/dL

According to the ACR, due to modest increased risk, restricting contrast medium use or pre-medicating solely based on patient age or gender is not recommended 

True 

ACR data suggest that it is not safe for the mother to continue breast-feeding following the administration of IV contrast 

False 

This is a condition or circumstance that suggest that a particular technique or drug should not be used in the case in question 

Contraindication 

The best equation for estimating GFR from serum creatine in children is the:

Bedside Schwartz equation 

What exams or studies typically use double-contrast?

• BE

• UGI

• arthrography 

Which types of contrast media is best for patient with a history of allergic reactions?

• gastrografin

• hypaque 

• water-soluble contrast 

• MD-gastroview 

What are ways to reduce the viscosity of iodinated contrast agents prior to injection?

• manually using tepid (slightly warm) water 

• use of a contrast warmer

• heating the contrast agent to body temperature