Intro to Radiology Flashcards
What amount of radiation results in sickness and death within a few weeks?
a) 1 sV
b) 2 sV
c) 10 sV
d) 15 msV
10 sV = 10,000 msV
1 sV radiation produces a ____% chance of eventually developing cancer
5.5%
What is the lowest dose of radiation at which cancer may occur in adults?
a) 10 sV
b) 15 msV
c) 50 msV
d) 1 sV
c) 50 msV
How much radiation is given by a CT abd/pelvis
a) 10 sV
b) 15 msV
c) 50 msV
d) 1 sV
b) 15 msV
Exposure of radiation is additive up until how long of a time period
a) 1 week
b) 1 month
c) 1 year
d) 10 years
e) unknown
e) unknown
In an x-ray, the farther the object is from the screen/detector the ______ it appears
larger
True/False: With increased photon energy, you have increased absorption
False
True/False: With increased photon energy, you have increased penetration
True
True/False: With increased photon energy, you have increased dose of radiation to patient
False
Why is PA more common than AP for chest x-rays?
Because PA gives more accurate size of heart (closer to heart)
In which situation would you order an AP CXR over a PA CXR?
a) to view cardiomegaly
b) to view right sided rib fractures
c) to view right sided pneumothorax
d) more than two of the above
d) more than two (b+c)
What causes structures to appear black on XR?
a) increased density
b) decreased density
c) increased thickness
b)
What type of contrast is best for those with impaired kidney function
a) LOSM
b) IOSM
c) HOSM
b) isoelectric
Rank the following from most radiolucent (black) to least radiolucent (white): fat, spongy bone, compact bone, water and most tissues, air
air, fat, water and most tissues, spongy bone, compact bone
What four things determine the contrast produced when an x-ray beam passes through the body? Which can be manipulated?
atomic number, thickness of object, density of object, penetrating characteristics of beam
latter can be manipulated
Why is barium useful for radiology of GI tract?
It provides better mucosal structure detail
Why does barium give better contrast than air?
Barium is much more dense (3.5 vs 0.00129) and has a higher atomic number (56 vs 7.64)
Other than barium, what organs do contrast media for ionizing radiography pose a risk of toxicity to? (3)
kidneys, heart, neural tissue
What XR view of the abdomen would be shot if the person was laying on their side with the beams going from front to back?
lateral decubitus
Air liquid interfaces give information on structures and ____ of patient
position
What do air liquid interfaces look like in pneumothorax?
Normally straight line, but in pneumothorax will be curved. Lung pulling away from chest wall