Ch. 3 TEST MATERIAL Flashcards
The atomic number of iodine is:
53
The atomic number of barium is:
56
Place the following tissue densities in order of easiest to hardest to penetrate by x-ray:
Lung
Muscle
Fat
Bone
Lung
Fat
Muscle
Bone
The total reduction in the number of x rays remaining in an x ray beam after penetration through a given thickness of tissue is called:
attenuation
Place the following tissue densities in order of hardest to easiest to penetrate by X-ray:
Lung
Muscle
Fat
Bone
Bone
Muscle
Fat
Lung
Coherent scattering is an interaction between low energy x rays and _____
Whole atoms
An x ray image results from the difference between those x rays absorbed photoelectrically in the patient and those transmitted to the image receptor.
This difference in x ray interaction is called ____
Differential absorption
air is considered a negative contrast agent
True or False
True because it appears dark on an image due to low-density
X rays throughout the diagnostic range can undergo an interaction with outer-shell electrons that not only scatters the x ray but reduces its energy and ionizes the atoms as well.
This interaction is called:
Compton Scatter
What type of x-ray interaction with matter is the source of most of the occupational radiation exposure that radiographers receive?
Compton Scattering
How could you decrease quantum noise in a digital image?
(fill in the bank on the test)
Increase mAs
The principal source of radiographic fog is _______.
scatter
How can a technologist compensate for the involuntary motion of the patient?
Short exposure time
Which factor has the greatest effect on size distortion?
OID
Which factor would cause an increase in spatial resolution?
long SID
The two types of shape distortion are:
Elongation and Foreshortening
High contrast; short scale or long scale?
Short scale ( few shades of gray)
long low lots of gray
What is considered to be the most detrimental to spatial resolution and the number one cause of repeat X-rays?
Motion blur
Fat tissue absorbs less radiation than muscle because fat tissue has a lower:
density
As compared to the patient with a 24 cm thick abdomen, imaging a patient with a 30 cm thick abdomen will result in ___________ scatter being produced and ________ image contrast
more, lower