Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Medical Imaging > Quiz 1 > Flashcards

Quiz 1 Flashcards

You may prefer our related Brainscape-certified flashcards:
USMLE® Step 1 flashcards
1
Q

Which scans measure anatomical structures mostly?

A

X-rays, CT scans and MRI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which scans are used to measure function?

A

PET, SPECT, fMRI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

spot=

A

pixel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

shades are coded by

A

number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

white code?

A

256

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

black code?

A

0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

1 bit gray scale images have

A

2 options: 0, or 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

2 bit gray scale images have

A

4 options

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

in gray scale when we increase the number of options its called…

A

bit resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

when we increase the number of pixels in gray scale resolution its called…

A

spatial resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

bit and spatial resolution is associated with…

A

file size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

RGB color code is usually in what format?

A

XX (Red) XX (green) XX (blue) FF thrown in there too for increased saturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

gray scale is what combination of the three colors?

A

equal intensity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

example of coding for saturated red?

A

FF0000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Example of coding for saturated green?

A

00FF00

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

example of coding for saturated blue?

A

0000FF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

example for grey scale?

A

454545 or 999999 (Anything repeating)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In CMY coding, what is used for black?

A

K

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

numbering systems used to code that were talked about?

A

TIFF and JPEG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Other systems that are completely different?

A

JAVA and Matlab

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does noise equate to in images?

A

differences in pixels that are not related to anatomy or physiology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What can reduce noise?

A

filters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do we get texture in images?

A

photographers use shadows. But texture can be created by organization of pixel grayscale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

texture can look …or…

A

fine or course

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

fine texture comes from …pixels and course texture comes from …pixels

A

small

large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the steps in texture analysis?

A
  1. measure range or difference between max and min intensity of neighboring pixels. the brighter the area, the more texture.
  2. texture segmentation-give an outline
  3. variance-calculate the sum of the square of differences in intensity between neighbors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

step two in texture analysis: texture segmentation?

A

boundaries between textures analyzed (to give outline)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

step three in texture analysis: variance?

A

calculate the sum of the squares of differences in intensity between neighbors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

smoothing can also be called…

A

blurring.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

smoothing looks at the color or grayscale and ….

A

averages to nearby

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

edge detection is…

A

an automated way to detect changes in tissue (or a discontinuity in the intensity or pattern of pixels)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

3 kinds of edge detection?

A

step edges, line edges, ramp edges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

step edges

A

detects sudden change from one value to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

line edges

A

abrupt change, but then returns to previous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

ramp edges

A

gradual changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

edge enhancement can help how clinically?

A

volume of blood in the heart at the end of diastole or systole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

shape analysis gives us what?

A

a region of interest (ROI)

38
Q

What is registration?

A

process of bringing 2 or more images into spatial correlation or matching.

39
Q

What is intermodal registration?

A

using images from different imaging techniques (MRI+CT)

40
Q

in registration the …. between different structures is transformed to match.

A

spatial relationship

41
Q

registration allows following

A

the patient over time (like annual mammograms or tumor prognosis)

42
Q

What are two types of registration errors?

A

point-based, target

43
Q

When were X-rays first discovered/used? and by whom?

A

late 1880s; wilhelm roentgen

44
Q

What did Wilhelm use to discover X-ray capability?

A

ran an electrical current through a glass tube and saw a faint green light

45
Q

What did he do after his initial light picture?

A

put a vacuum in the tube and the light increased

46
Q

Why did he name it X-ray?

A

it meant there was light coming from somewhere unknown and it was meant to be changed and wasnt.

47
Q

earliest xrays were produced with

A

gas tubes

48
Q

in the earliest xrays, penetration was dependent on? Intensity was dependent on?

A

voltage

current.

49
Q

in the earliest xrays if they reduced gas pressure what happened? What did they do to eliminate the problem?

A

the current fell and they would lose clarity of the picture. tungsten filament in the 1900s

50
Q

What 2 things make xrays different?

A
  1. they can penetrate matter

2. they ionize gasses which is how xrays are created.

51
Q

xrays were originally made in…Why?

A

a tube; electrons move more quickly in the tube and hit the tungsten.

52
Q

the xrays in the tube released a … called…

A

photon; Bremsstrahlung radiation

53
Q

not all electrons that hit the tungsten will produce photons, most lose …. so tungsten must be able to withstand high heat and …the heat away from the tube.

A

energy producing heat; conduct

54
Q

xrays are considered ….

A

electron accelerators

55
Q

penetration of xrays are dependent on the ….. at which the electrons hit the target.

A

speed

56
Q

speed of electrons is dependent on ….across tube.

A

voltage

57
Q

absorbed photons in the body ….usually a …. in the body.

A

bind to something; receptor (accepter molecule)

58
Q

reflected photons …

A

do not enter the body

59
Q

transmitted photons…

A

pass directly through material

60
Q

refracted photons …

A

travel through, but the angle is altered

61
Q

3 tissues easiest to differentiate in x rays

A

bone, lungs, soft tissue

62
Q

bone=

A

high absorption

63
Q

lungs=

A

low absorption

64
Q

soft tissue=

A

middle

65
Q

xrays are the chosen method for…

A

bone fractures

66
Q

xrays have better …than MRI or ultrasound

A

spatial resolution

67
Q

xray film is called

A

radiograph

68
Q

as photons hit the film it turns…

A

dark

69
Q

the more dense the material (more absorption) the …

A

lighter the film

70
Q

xrays can cause damage to cells that are coded for being cancerous. energy will bounce from once cell to another causing damage, this is called

A

ionization

71
Q

….is most sensitive to ionization

A

DNA

72
Q

body is able to repair most damage by ….

A

apoptosis

73
Q

xrays are …risk than other imaging techniques

A

higher

74
Q

single chest xray is …% of radiation for a year

A

20%

75
Q

CT developed in

A

1917

76
Q

first CT equipment used in…

A

1970s

77
Q

used … for CT scans like early xrays. now they are ….components

A

gas tubes; solid state

78
Q

CTs are ….of different Xray slices that could be looked at from different angles.

A

registration

79
Q

today, rotating xray beam collects…

A

emitted electrons

80
Q

single image in the entire series is called

A

comograph

81
Q

CAT

A

computed axial tomography

82
Q

in CT beam can be sent out as …or…

A

fan or parallel

83
Q

typically the xray beam in a CT must rotate ….degrees to get the best images. in fan mode it needs… degrees.

A

360; 180

84
Q

beam in a CT hits …

A

more than 1 detector at a time

85
Q

kernels are

A

filters for 3D; they typically sharpen or blur the image

86
Q

CT data has more …than xray and high pass filter increases it.

A

noise

87
Q

two types of reconstruction?

A

analytical, iterative

88
Q

analytical reconstruction uses…

A

algorithms based on anatomical points

89
Q

iterative reconstruction uses…

A

assumption and compare to assumptions with measured data and it continue to makes adjustments

90
Q

compared to xrays, CT slices are ….

A

very thin so radiation is lower

91
Q

newer generations of scanners perform …

A

very low dose scans with more sensitive detectors and faster rotator speeds.

Medical Imaging (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions