Ch. 8 Image Production

Question 1

the x-ray photons removed from the x-ray beam as a result of the uptake of their energy by body tissues

Answer 1

absorption

Question 2

reduction in the energy or number of photons in the primary x-ray beam after it interacts with anatomic tissue

Answer 2

attenuation

Question 3

an interaction that occurs with low-energy x-rays, typically below the diagnostic range. The incoming photon interacts with the atom, causing it to become excited. The x-ray does not lose energy but changes direction

Answer 3

coherent scattering

Question 4

scattering that results from the loss of some energy of the incoming photon when it ejects an outer-shell electron from a tissue atom

Answer 4

Compton effect

Question 5

the electron ejected from an atom during a Compton scattering event

Answer 5

Compton electron

Question 6

used to describe the ability of the imaging system to distinguish between small objects that attenuate the x-ray beam similarly in digital imaging

Answer 6

contrast resolution

Question 7

the difference between the x-ray photons that are absorbed photoelectrically versus those that penetrate the body

Answer 7

differential absorption

Question 8

the range of exposure intensities that an image receptor can respond to and acquire image data

Answer 8

dynamic range

Question 9

the attenuated x-ray beam leaves the patient and is composed of both transmitted and scattered radiation; also called remnant radiation

Answer 9

exit radiation

Question 10

the use of a continuous beam of x-rays to create dynamic images of internal structures that can be viewed on a display monitor

Answer 10

fluoroscopy

Question 11

unwanted exposure on the radiographic image that does not provide any diagnostic information

Answer 11

fog

Question 12

a device that receives the radiation leaving the patient

Answer 12

image receptor

Question 13

the removal of an electron from an atom

Answer 13

ionization

Question 14

the invisible image that exists on the image receptor before it has been processed

Answer 14

latent image

Question 15

the visible radiographic image on the exposed detector after processing

Answer 15

manifest image

Question 16

combination of rows and columns (array) of pixels that make up a digital image

Answer 16

matrix

Question 17

in the diagnostic range, the total absorption of the incident photon by ejecting an inner-shell electron of a tissue atom

Answer 17

photoelectric effect

Question 18

the electron ejected from an atom during a photoelectric interaction

Answer 18

photoelectron

Question 19

picture element; the smallest component of the matric, which is represented as a single brightness level on a computer monitor

Answer 19

pixel

Question 20

also called number of bits, it affects the number of shades of gray available for image display

Answer 20

pixel bit depth

Question 21

the attenuated x-ray beam leaving the patient that is composed of both transmitted and scattered radiation; also called exit radiation

Answer 21

remnant radiation

Question 22

incoming photons are not absorbed but instead lose energy during interactions with the atoms composing the tissue

Answer 22

scattering

Question 23

the ejected electron resulting from the Compton effect interaction; also called Compton electron

Answer 23

secondary electron

Question 24

matter per unit volume, or the compactness of the atomic particles composing the anatomic part

Answer 24

tissue density

Question 25

x-ray photons that pass through the body to expose the image receptor

Answer 25

transmission

Question 26

occurs when the primary x-ray beam loses energy as it interacts with anatomic tissues

Answer 26

attenuation

Question 27

what is beam attenuation affected by

Answer 27

• tissue thickness
• atomic number
• tissue density
• x-ray beam quality

Question 28

x-rays can eject electrons from atoms within anatomic tissue called

Answer 28

ionization

Question 29

3 primary processes that occur during x-ray interaction with anatomic tissues

Answer 29

• absorption
• transmission
• scattering

Question 30

total absorption of the incoming x-ray photon is a result of what

Answer 30

photoelectric effect

Question 31

scattering of the incoming x-ray photon is a result of what

Answer 31

Compton effect

Question 32

this determines the available shades of gray to display the digital image or its contrast resolution

Answer 32

pixel bit depth

Question 33

what type of dynamic range do digital IRs have

Answer 33

wide dynamic range

Question 34

what type of dynamic range do film-screen IRs have

Answer 34

limited dynamic range

Question 35

this allows imaging of the movement of internal structure for viewing on a display monitor

Answer 35

fluoroscopy

Question 36

what describes the process of radiographic image formation

Answer 36

differential absorption

Question 37

the range of exposure intensities an image receptor can accurately detect defines what

Answer 37

dynamic range

Question 38

what will increasing the pixel bit depth do

Answer 38

increase contrast resolution

Question 39

what type of imaging system uses an intensifying screen to convert x-rays to visible light

Answer 39

film-screen