CH.3 Flashcards Preview

RAD-BIO > CH.3 > Flashcards

Flashcards in CH.3 Deck (25):
1

the amount of energy absorbed by the patient per unit mass is referred to as:

absorbed dose

2

the highest energy level of photons in the x-ray beam "quality"

kVp

3

the product of electron tube current and the amount of time in seconds that the x-ray tube is activated "quantity" (controls density/dose)

mAs

4

If an interaction occurs, electromagnetic energy is transferred from the x-rays to the atoms of the patient's biologic material. This process is called?

absorption

5

When an x-ray beam passes through a patient, it goes through a process called:

Attenuation

6

slowing down or diminishing the x-ray photon/beam energy/intensity is called:

Attenuation

7

Two types of transmission?

Direct and Indirect

8

when primary x-rays go through the patient without interacting is called:

Direct transmission

9

x-ray photons that are deflected or scattered with potential loss of energy is called:

Indirect transmission

10

____ ____ is the x-ray photon beam that emerges
from the x-ray tube and is directed toward the image
receptor

primary radiation

11

Attenuation refers to both:

scatter and absorption

12

Several methods have been devised to limit the effects of indirectly transmitted x-ray photons. The most common methods include:

1. Air gap technique
2. Radiographic grids

13

Air gap technique and radiographic grids are ways to reduce ____

scatter

14

Only 2 photons emerge from the tissue and strike the IR below it. They are referred to as:

exit, or image-formation photons

15

bending of the its path

small-angle scatter

16

____-____ _____ degrades the appearance of a completed radiographic image by blurring the sharp outlines of dense structures

small-angle scatter

17

Before the four photons produced by the x-ray source enter human tissue, they are referred to as:

primary photons

18

five types of interactions between x-radiation and matter are:

1. Coherent scattering
2. Photoelectric absorption
3. Compton scattering
4. Pair production
5. Photodisintegration

19

what 2 interactions between x-radiation and matter are important in diagnostic imaging?

Compton and Photoelectric absorption

20

interaction between x-ray and inner-shell electron; the electron is ejected and called a photoelectron.

Photoelectric absorption

21

Other terms for coherent scattering

Classical/elastic/unmodified

22

Pair production is important in ____ radiology

therapeutic

23

Photodisintegration is important in ____ scans

PET

24

Contrast =

window width

25

window level controls the ___

density