NMTCB CT -IV PROCEDURES &
CONTRAST EXAM QUESTIONS AND
ANSWERS 100% CORRECT
Contrast indications - ANSWER--improve sensitivity and specificity for diagnosis
- enhance perfused tissues
- iodine increases attenuation of the X-ray beam and causes enhancement
Negative contrast agents - ANSWER-air and water
used to distend the structure and improve the visualization of internal surface
5 types of contrast - ANSWER-- intravenous
- oral
- rectal
- intrathecal
- intraarticular
intraveneous contrast
- iodine agent
- osmolarity characteristic - ANSWER-iodine
- increases brightness so a higher CT number is assigned to the tissue on the image
- distinguishes structures
- greater osmolarity than blood plasma = 285mOsm/kg
- hyperosmolar solution (hypertonic)
injection rates - ANSWER-slow
- administering a more viscous agent
high
- larger volumes and high concentrations are associated with increased instance of
adverse reactions
- helical scans - contrast given at faster rate
- increase in the density of the perfused regions
- trigger chemotaxis reactions
contrast concentration - ANSWER-higher concentration of iodine has increase in
attenuating the X-ray photons and better enhancement
higher dose = high concentration
, IV contrast for pregnant women - ANSWER-- only when diagnostic info cannot be
obtained through other imaging modalities
- clinical info needed will affective care of pt or fetus during pregnancy
- withheld breastfeeding for 24 hours
ionic vs nonionic agents - ANSWER-ionic
- divide into charged particles in a solution (bloodstream)
nonionic
- particles remain intact
- less breakdown into greater charged particles
- better tolerated
examples of ionic contrast - ANSWER-cystografin
gastrografin
hypaque
gastroview
examples of non ionic contrast - ANSWER-visipaque
isovue
optiray
oxilan
ultravist
osmolarity - ANSWER-concentration of molecular particles in the contrast agent solution
LOCM - ANSWER-low osmolar contrast media
aka non ionic contrast
- contains a lower concentration of particles =
500-850mOsm/kg
- better tolerated
HOCM - ANSWER-high osmolar contrast media
aka ionic contrast
high concentration solution = 1300 - 1600 mOsm/kg
viscosity
- definition
- low vs high - ANSWER-- measure of thickness of a liquid related to the frictional force
of the molecules of the substance as they flow past another
- warming reduces
low
- better tolerated
CONTRAST EXAM QUESTIONS AND
ANSWERS 100% CORRECT
Contrast indications - ANSWER--improve sensitivity and specificity for diagnosis
- enhance perfused tissues
- iodine increases attenuation of the X-ray beam and causes enhancement
Negative contrast agents - ANSWER-air and water
used to distend the structure and improve the visualization of internal surface
5 types of contrast - ANSWER-- intravenous
- oral
- rectal
- intrathecal
- intraarticular
intraveneous contrast
- iodine agent
- osmolarity characteristic - ANSWER-iodine
- increases brightness so a higher CT number is assigned to the tissue on the image
- distinguishes structures
- greater osmolarity than blood plasma = 285mOsm/kg
- hyperosmolar solution (hypertonic)
injection rates - ANSWER-slow
- administering a more viscous agent
high
- larger volumes and high concentrations are associated with increased instance of
adverse reactions
- helical scans - contrast given at faster rate
- increase in the density of the perfused regions
- trigger chemotaxis reactions
contrast concentration - ANSWER-higher concentration of iodine has increase in
attenuating the X-ray photons and better enhancement
higher dose = high concentration
, IV contrast for pregnant women - ANSWER-- only when diagnostic info cannot be
obtained through other imaging modalities
- clinical info needed will affective care of pt or fetus during pregnancy
- withheld breastfeeding for 24 hours
ionic vs nonionic agents - ANSWER-ionic
- divide into charged particles in a solution (bloodstream)
nonionic
- particles remain intact
- less breakdown into greater charged particles
- better tolerated
examples of ionic contrast - ANSWER-cystografin
gastrografin
hypaque
gastroview
examples of non ionic contrast - ANSWER-visipaque
isovue
optiray
oxilan
ultravist
osmolarity - ANSWER-concentration of molecular particles in the contrast agent solution
LOCM - ANSWER-low osmolar contrast media
aka non ionic contrast
- contains a lower concentration of particles =
500-850mOsm/kg
- better tolerated
HOCM - ANSWER-high osmolar contrast media
aka ionic contrast
high concentration solution = 1300 - 1600 mOsm/kg
viscosity
- definition
- low vs high - ANSWER-- measure of thickness of a liquid related to the frictional force
of the molecules of the substance as they flow past another
- warming reduces
low
- better tolerated
