Bryan - Diagnostic Imaging - Test 1 - Winter 2Nd Year

Front 1

What is the wavelength range for x-rays?

Back 1

0.01 to 10nm

Front 2

T or F
Wavelength has no effect on x-ray energy.

Back 2

False. Shorter wavelengths afford greater energy.

Front 3

What three things modulate x-ray absorption in a tissue?

Back 3

Tissue density (eg: bone vs fat)
Atomic # of elements in the tissue
Thickness of tissue

Front 4

What are the 5 radiodensities?

Back 4

1 - air
2 - fat
3 - water (soft tissue)
4 - bone
5 - metal

Front 5

What are the main parts of a radiograph machine?

Back 5

Generator
Control panel
Tube (anode + cathode)

Front 6

What parameters can usually be controlled at the control panel of a radiograph?

Back 6

on/off
mA (current in milliamperes)
kVp (energy in peak kilovolts)
s (time in seconds)

Front 7

The total number of electrons crossing the tube describes the_________ parameter.

Back 7

mA (current)

Front 8

Increased x-rays is a result of increasing which parameters?
kVp
mA
mAs
s

Back 8

Any one of these will increase x-rays

Front 9

Increased median x-ray energy is a result of increasing which of the following parameters?
kVp
mA
mAs
s

Back 9

kVp

Front 10

What components are necessary to produce x-rays?

Back 10

source (cathode)
accelerating device
target (anode)

Front 11

What material comprises the source in most medical radiograph machines? What material comprises the target?

Back 11

Source (cathode) = W
Target (anode) = W on top of Cu (for heat dissipation)

Front 12

This graph depicts an increase in which of the following parameters:
kVp
mA
mAs
s

Back 12

mA

Front 13

This graph depicts an increase in which of the following parameters:
mA
mAs
kVp
s

Back 13

kVp

Front 14

What are the two main types of x-ray radiation?

Back 14

Bremsstrahlung radiation
Characteristic radiation

Front 15

Choose characteristic or Bremsstrahlung radiation...
...characterized by discrete energy peaks.

Back 15

Characteristic radiation

Front 16

Choose characteristic or Bremsstrahlung radiation...
...energy produced by the deceleration by a second charged particle.

Back 16

Bremsstrahlung radiation

Front 17

Choose characteristic or Bremsstrahlung radiation...
...radiation in a continuous background spectrum.

Back 17

Bremsstrahlung radiation

Front 18

Choose characteristic or Bremsstrahlung radiation...
...energy released when electrons from an outer energy level drop to a lower energy.

Back 18

Characteristic radiation

Front 19

Match the kVp value (low, medium, high) to the part being radiographed.

Fast moving structure
Distal extremity
Shoulder region
Pelvic region
Thorax
Slow or non-moving structure

Back 19

Fast moving structure - high
Distal extremity - low
Shoulder region - medium
Pelvic region - medium
Thorax - high
Slow or non-moving structure - low

Front 20

What is the range for low kVp? Medium? High?

Back 20

low = 45-60
med = 65-75
high = >80

Front 21

What are two major problems with scattered radiation in radiography?

Back 21

Safety concern
Reduced image quality

Front 22

What are some techniques used to minimize scatter in order to achieve better image quality?

Back 22

Reduce area of tissue irradiated
Add Pb layer under cassette
Use a grid
Use higher kVp

Front 23

What unit denotes the absorbed dose of radiation? What is this unit equal to?

Back 23

Gray (Gy) = 1 joule/kg

Front 24

What unit denotes the rate of radioactive decay? What is this unit equal to?

Back 24

Becquerel (Bq) = 1sec^-1;
also a Curie

Front 25

What unit denotes the ability of radiation to ionize air? What is this unit equal to?

Back 25

Roentgen (R) = 2.58E^(-4) C/kg

Front 26

What unit measures the dose equivalent? What is this unit equal to?

Back 26

Sievert (Sv) = Gray x q.f. = 100rem

Front 27

Which of the following are sources of radiation?

a) Cosmic radiation
b) Background radiation in food
c) Xe gas
d) Medical radiographs
e) Weapons fall-out; nuclear reactor accidents
f) Old orange fiestaware

Back 27

All of the above are EXCEPT for the Xe gas...try Rn gas instead!

Front 28

What is the non-occupational exposure legal radiation limit?
What is the occupational exposure legal radiation limit?
Occupational limit if pregnant?

Back 28

non-occupational < 100 mem/yr
occupational < 5 rem/yr
occupational/preggo < 500 mrem/yr

Front 29

What are the 3 sources of radiation in radiology?

Back 29

Scattered radiation
Primary Beam
Leakage from x-ray tube

Front 30

What are the 2 ways of monitoring radiation exposure?

Back 30

Film badges
TLD (thermoluminescent detector)

Front 31

What is the ALARA principle?

Back 31

As Low As Reasonably Achievable

Front 32

Which are ways to minimize radiation exposure to the radiographer?

a) use barriers
b) use lead body shielding
c) stand far away
d) manually restrain patient to minimize necessary exposures

Back 32

A B and C are correct

Front 33

What is contained inside the cassette?

Back 33

screen + film

Front 34

What information should be entered in pre-processing of radiographs?

Back 34

Name of owner
Name of animal
Date
Marker (L vs. R)
Clinic
Vet/vet tech

Front 35

What information should be entered in post-processing of radiographs?

Back 35

NONE! post processing is NOT ok!

Front 36

What term describes the degree of blackening of the film?
Which parameter has the MOST effect on this?

Back 36

Radiographic density; mA (or mAs)

Front 37

What term describes the range of gray shades on a film? Which parameter has the MOST effect on this?

Back 37

Contrast; kVp

Front 38

The amount of detail in a radiograph is known as...

Back 38

...resolution

Front 39

What are the three types of radiography?

Back 39

Conventional
Fluoroscopy
Digital

Front 40

What are the 2 types of digital radiography?

Back 40

computerized and direct

Front 41

T or F:
In computerized radiography, there is no need for a film cassette.

Back 41

False! This describes direct digital radiography.

Front 42

What is the universal diagnostic imaging file format extension?

Back 42

.dicom

Front 43

What are the 6 Rotengen signs?

Back 43

Number
Position
Size
Shape
Opacity
Margination (architectural pattern)

Front 44

What is the minimum number of views that should be taken?

Back 44

2

Front 45

Doubling the mAs is equivalent to what change in kVp?

Back 45

increasing kVp by 15%

Front 46

Decreasing kVp by 27.75% (2 15% reductions) is equivalent to what change in mAs?

Back 46

decreasing mAs by 3/4

Front 47

What will be the impact on latitude, blackness, and contrast when...
...increasing kVp by 15% and decreasing mAs by 50%?

Back 47

latitude - increase
blackness - no change
contrast - decrease

Front 48

T or F:
Increasing kVp increases contrast.

Back 48

False! It decreases contrast (reduces the shades of gray)

Front 49

What will be the impact on latitude, blackness, and contrast when...
...decreasing kVp by 15% and increasing mAs 100%?

Back 49

Latitude - decrease
Blackness - no change
Contrast - increase

Front 50

When should a grid be used (ie, what is the cutoff thickness)?

Back 50

>11cm

Front 51

T or F:
Photographic film is very sensitive to x-ray exposure.

Back 51

False!
Actually, only ~10% of film exposure is due to directly to x-rays.

Front 52

T or F:
There is no way to discern if a structure is above or below another structure in a single radiograph.

Back 52

True (mostly)...
This is why you need 2 views.
You can, however, use the magnification effect to determine which structures are farther from the film.

Front 53

What are the four common radiographic views of the equine carpus?

Back 53

DP
Lateromedial
Medial oblique
Lateral oblique

Front 54

ID this radiographic view of the equine carpus.

Back 54

Dorsopalmar

Front 55

ID this radiographic view of the equine carpus.

Back 55

Medial oblique

Front 56

ID this radiographic view of the equine carpus.

Back 56

Lateral oblique

Front 57

ID this radiographic view of the equine carpus.

Back 57

Lateromedial