Imaging Basics

Question 1

When a metal is heated to incandescence (glowing), electrons from the outermost shell are released

Answer 1

Ionic emission

Question 2

Removal of an outer orbital electron that leaves the atom positively charged. Energy for removal must be greater than the atom’s binding energy

Answer 2

Ionization

Question 3

Produce chemical and biological changes in matter through ionization and excitation

Answer 3

Roentgen’s Rays

Question 4

X-Rays are produced by the collision of fast moving ____ with matter

Answer 4

electrons

Question 5

99% of the energy produced at the target is given off as ____

Answer 5

heat

Question 6

Only ___ of the energy is converted into Xrays

Answer 6

1%

Question 7

What is the source of electrons

Answer 7

cathode

Question 8

Positive electrode made of tungsten mounted on a copper block; where the primary beam originates

Answer 8

Anode

Question 9

Area of target hit by electrons

Answer 9

Focal spot

Question 10

Negative electrode consisting of a tungsten filament within a focusing cup, where electron cloud is generated

Answer 10

Cathode

Question 11

Houses anode and cathode in a vacuum

Answer 11

Glass tube

Question 12

Protects and insulates glass envelope and decreases stray xray emissions

Answer 12

Oil and metal housing

Question 13

Area of xray tube where primary beam exits

Answer 13

Window

Question 14

Aluminum filter at window to absorb the low energy xrays and increase the high energy photons in the primary beam

Answer 14

Added filtration

Question 15

The useful xrays that exit the window of the tube

Answer 15

Primary beam

Question 16

Low energy, longer wavelength, less penetrating, lower kVp

Answer 16

Soft Xrays

Question 17

High energy, shorter wavelength, greater penetrating, higher kVp

Answer 17

Hard Xrays

Question 18

What determines hard/soft xrays?

Answer 18

Density of subject matter

Question 19

Refers to the apparent decrease in the size of the spot by the use of an angled target surface

Answer 19

Effective focal spot

Question 20

Smaller focal spot = ___ image

Answer 20

sharper image

Question 21

Place the thickest portion of the animal near the ____

Answer 21

cathode

Question 22

Controls the amount of power, time and the release of the xray beam

Answer 22

electrical components

Question 23

High voltage circuit causes acceleration of the electrons from the ____ to the ____

Answer 23

Cathode to the anode

Question 24

Increases incoming voltage into the thousands of volts or kilovolts to make electron speed fast

Answer 24

Step up transformer

Question 25

Allows predetermined voltage to step transformer; attached to kVp selector

Answer 25

Autotransformer

Question 26

Provides electricity necessary to heat filament of cathode to release electrons

Answer 26

Low voltage circuit

Question 27

Reduces the incoming line voltage so that filament is not damaged by voltage necessary for electron acceleration

Answer 27

Step down transformer

Question 28

Connected to mA selector, controls release of electrons and number of xrays produced

Answer 28

Step down transformer

Question 29

Controls duration of length of xray exposure

Answer 29

Timer Switch

Question 30

Short exposure times =

Answer 30

less scatter or operator exposure

Question 31

Beam limitation, also known as ?

Answer 31

Collimation or Coning down

Question 32

Sheets of lead with rectangular, square or circular openings that are inserted in window

Answer 32

Aperture Diaphragm

Question 33

What are the quantitative factors

Answer 33

mA, time (sec), kV, distance, filtration

Question 34

What quantitative factors control intensity

Answer 34

mA and time

Question 35

What is the qualitative factor?

Answer 35

kV

Question 36

Electrons are produced by heating the _____ filament

Answer 36

cathode

Question 37

Electrons are measured in \_\_\_

Answer 37

mA's

Question 38

Higher mA allows for a _____ time and also allows for examining ____ areas

Answer 38

shorter, thicker

Question 39

Determines the degree of blackness of radiographic density of the image

Answer 39

mA-s

Question 40

mA-s remains ____ for the body region being radiographed

Answer 40

constant

Question 41

Can affect detail by causing an image to be too light or too dark for structures to appear clearly

Answer 41

mAs

Question 42

Determines the penetrating power or energy level of the resulting Xray beam

Answer 42

kVp

Question 43

kVp setting is determined by what?

Answer 43

Measurement of body part with caliper

Question 44

What is Sante's rule?

Answer 44

(cm X 2) + SID + Grid Factor = kVp

Question 45

Low kVp is also called ?

Answer 45

High contrast

Question 46

High kVp is also called?

Answer 46

Long-scale contrast

Question 47

Distance from focal point on anode to film

Answer 47

SID

Question 48

Normal SID

Answer 48

36-42 inches

Question 49

SID has a direct relationship to ?

Answer 49

mA-s

Question 50

SID is inversely related to?

Answer 50

Density

Question 51

Inverse Square Law

Answer 51

The intensity of he xray beam varies inversely according to the square of the distance

Question 52

A change in the _____ has the same effect as a change in the mAs

Answer 52

distance

Question 53

Primary cause of operator exposure

Answer 53

scatter

Question 54

Whether tissure absorbs xrays or allows to penetrate through is dependent on:

Answer 54

Atomic number and density of tissue, and wavelength of xray

Question 55

What should be the first adjustment?

Answer 55

mAs

Question 56

What is true if the image is too light?

Answer 56

Low density, low contrast, low detail

Question 57

What is true if the image is too dark?

Answer 57

High density, low contrast, low detail