Contrast Media Flashcards
What are two reasons contrast media is used during a CT procedure?
Increase contrast between and visibility of an atomic and pathological conditions
What two basic types of contrast are used in CT procedures?
Positive and negative
What class of substances do positive contrast agents belong to?
Radiopaque contrast media (RCM)
Name the two types of RCM used for CT?
Iodine and barium
Degree of radiopacity if an iodinated contrast agent is directly proportional to the agents concentration of what?
Iodine
The degree of radiopacity by a barium contrast agent is directly proportional to the agents what?
Concentration or barium
What are 5 ways that water-soluble iodinated contrast media may be administered?
Intravenously, directly into vein or artery, intrathecal/spinal canal, joint space, and orally/GI tract
What contrast medium is used to opacity the GI tract?
Barium sulfate
At what point of contrast opacification of vessels allows for visualization and differentiation from surrounding structures?
Initial opacification
What are three examples of diagnosis that contrast media aids in by opacifying these structures?
Aneurysm, thrombus, and stenosis
After a period of time, where is contrast media distributed in the body?
Extravascular space
What is the extravascular space?
Outside the blood vessel
Where is the intravascular space?
Inside the bloodstream
What can the interstitial redistribution of contrast aid in the diagnosis of soft tissue pathology?
Differentiate between normal and abnormal ST
What part of the kidneys becomes opacification as a result of kidney excretion or the contrast?
Renal collecting system
What structures are considered a part of the renal collecting system?
Renal pelvis, ureters, and bladder
What process describes contrast media’s propensity to cause fluid from outside the blood vessel to move into the bloodstream?
Osmolality
What are two main categories for iodinated RCM?
Ionic contrast media and no ionic contrast media
Which iodinated RCM is made of salts consisting of sodium and/or meglumine?
Ionic contrast media
What distinguishes ionic from nonionic contrast?
Ionic molecules disassociate in the blood stream whereas no ionic does not
How many iodine atoms are in one molecule of ionic contrast?
3
How many charged particles, from the one ionic molecule, disassociate when it interacts with the bloodstream?
2
What is indicated when osmotic ions are created?
High-osmolar contrast media
What are examples of HOCM?
Conray and Hypaque
