7.1 Reporting Flashcards
1
Q
analog image processing is applied on analog signals and can be _____
A
periodic and non-periodic
2
Q
The data collected from the patient during imaging is first converted into ____ to provide an input and output image, in an effort to improve and enhance diagnostic interpretation and management of images acquired from patients
A
digital data
3
Q
refers to a continuously changing signal recorded in its original form
A
analog
4
Q
In medical imaging for example, there are two types of images being generated –
A
analog and digital
5
Q
An output signal generated by the PMT with continuously varying intensity depending on the location of light on an image
A
Analog Signal
6
Q
The output of the photodetector is a time-varying _____ that is transmitted to a computer that has multiple functions
A
analog signal
7
Q
The time-varying analog signal from the photodetector is processed for ______. This shapes the signal before the final image is formed
A
amplitude, scale, and compression
8
Q
is an image formed by a 2D analog and digital signal that contains color information
A
Analog images
9
Q
It is generally continuous and not broken into tiny components because although analog signals are real-world, they do not produce good quality images
A
Analog images
10
Q
are subsequently displayed for human viewing and interpretation and in addition, these images can be digitally manipulated to suit the viewing needs of the observer
A
Analog images
11
Q
Examples of analog images include:
A
television images, photographs, paintings, and medical images
12
Q
is defined as numerical representation of the patient
A
Digital images
13
Q
is divided into a matrix or array of small picture elements, or pixels
A
Digital images
14
Q
that they can be processed, in many ways, by computer systems
A
Digital images
15
Q
a necessary element in all modern medical imaging methods
A
Digital images
16
Q
they are also easier to store, more accurate and reliable
A
Digital images
17
Q
subjecting numerical representations of objects to a series of operations in order to obtain a desired result
A
digital image processing
18
Q
Depending on how they are acquired, radiology images can be classified into two domains:
A
- Spatial Domain
2. Frequency Domain
19
Q
all images use a right-handed X-Y coordinate system, to identify the location of any number that makes up the image. The X-axis is used to describe the rows or lines on the image, while the Y-axis is used to describe the columns
A
Spatial Domain
20
Q
One of the main goals is to make image processing easier, so that particular features of the image can be enhanced or suppressed
A
Frequency Domain
21
Q
Images can also be acquired in the frequency domain using the mathematical procedure of the ____
A
Fourier transform
22
Q
a signal can be converted from time domain into frequency domain using mathematical operators called transforms
A
transformation
23
Q
In the Frequency Domain, High frequency components correspond to ____ in an image. While Low frequency components in an image correspond to _____
A
edges (high), smooth regions (low)
24
Q
in frequency domain,
the image can be enhanced for sharpness in which case the ______ are suppressed
A
low frequencies
25
in frequency domain, the image can be smoothed to enable better visualization of homogeneous structures by suppressing ______ via digital image processing
high frequencies
26
the purpose is to generate an image that is more pleasing to the observer
Image Enhancement
27
improvement of overall quality
Image Enhancement
28
Image Enhancement operations include
contrast enhancement, edge enhancement,
spatial & frequency filtering, imaging combining,
noise reduction
29
characteristics such as contour and shapes can be enhanced to improve such quality
Image Enhancement
30
improve images that have distortions or degradations
Image Restoration
31
a commonplace in “space craft", these are usually images sent to earth and usually they have the instance to be blurred out thus can be filtered to make them sharper
Image Restoration
32
it begins with image segmentation operations, such as image enhancement or restoration operations
Image Analysis
33
features of the objects are extracted resulting in measures that describe & characterize the image
Image Analysis
34
are used in 3D medical imaging such as CT & MRI; where the goal is to simplify the representation of an image into something much easier to analyze
segmentation operations
35
reduces the size to save storage and transmission time
Image Compression
36
compression wherein there is no loss of info
Lossless
37
compression wherein there is loss of info and significant in images that have unnecessary data
Lossy
38
The main advantage is that there is no loss in both SPATIAL & FREQUENCY INFO
Wavelet Compression
39
recent form of compression which offers an approach that allows to reduce the size of the data while at the same time improving its quality through the removal of high frequency noise components
Wavelet Compression
40
it creates images that may be physically impossible or does not exist at all
Image Synthsis
41
basis for the production of CT & MRI images
image reconstruction technique
42
based on computer graphics technology
3D visualization technique
43
a digital image is made up of a two-dimensional array of numbers
Matrix
44
consists of columns (M) and rows (N) that define small square regions called picture elements or pixels
Matrix
45
Matrix size selected by an operator for imaging examinations is sometimes referred to as the _____
field of view (FOV)
46
he pixel size can be calculated using the relationship:
Pixel size = FOV/Matrix size
47
Pixels in a digital image that represent the information contained in a tissue volume in the patient
Voxels
48
it includes the Height, width and length
Voxels 3D
49
inclusion of time, width, length and time
Voxels 4D
50
refers to the color information stored in an image
Bit Depth
51
implies that every pixel in the digital image matrix M x N is represented by k binary digits
k bits
52
The number of bits per pixel
Bit Depth
53
The characteristics of a digital image, that is, the ______,
can affect the appearance of the digital image, particularly its spatial resolution and its density
resolution
matrix size, the pixel size, and the bit depth
54
matrix size, the pixel size, and the bit depth
Spatial Resolution
55
linked to bit depth | range of gray levels per pixel
Density Resolution
56
5 different cassette sizes used in film-screen radiography:
```
8x10,
10x12,
11,14
14x14,
14x17
```
57
A typical CR image matrix size
2048 x 2048
58
There are three steps to digitizing an image:
1. scanning
2. sampling,
3. quantization
59
used to measure the brightness level
Photomultiplier Tube (PMT)
60
the image is first divided into an array of small square regions called pixels
Scanning
61
simply involves measuring the brightness level of each of the pixels using special devices such as a photomultiplier tube (PMT). The signal from the PMT is an analog signal (voltage waveform) that must be converted into a digital image for processing by a digital computer
Sampling
62
This is a process whereby the brightness levels obtained from sampling are assigned an integer (zero, a negative, or a positive number) called a gray level. The image is now made up of a range of gray levels. The total number of gray levels is called the gray scale
Quantization
63
one pixel value in the input image is mapped onto the same pixel location in the output image and depends on the input pixel value entire image is then transformed using what is referred to as pixel point process
Point processing operation
64
is most often used in digital imaging to change the contrast and brightness of an image displayed for viewing on a display monitor
Grayscale mapping (commonly known as “windowing”)
65
Image contrast and brightness transformations can be done using a variety of processing techniques two common methods used in digital radiology, the ______
look-up table (LUT) method, the windowing method
66
Changing the histogram of the image can alter the brightness and contrast of the image termed as
histogram modification/histogram stretching
67
Low-contrast image can be transformed into a high-contrast image using
Look-up table (LUT)
68
one in which the output image pixel value is obtained from a small
area of pixels around the corresponding input pixel.
Local processing operation
69
In Local processing operation, since a small area of pixels or group of pixels is
used, these operations are also referred to as _____
area or group processes
70
A notable example is that
of frequency filtering in which the process can sharpen, blur, smooth, and reduce the noise of an
image
Local processing operation
71
There are 4 different techniques in Local processing operation
1. Convolution
2. High – Pass Filtering
3. Low – Pass Filtering
4. Unsharp (Blurred) Masking
72
where a group of input image pixels surrounding the specific input pixel is used to
change the value of the output pixel value to arrive at a new value in the output image
Convolution
73
The group of pixels used to calculate this average in convolution is called
Convolution kernel
74
A typical kernel size is a _____
3 × 3 matrix2
75
During processing, the kernel scans across the entire image, pixel by pixel. Each input
image pixel, the pixels surrounding it, and the kernel are used to calculate the corresponding output
pixel value
Convolution
76
Suppresses the low frequencies, and the result is a much sharper image
than the original
High – Pass Filtering
77
Such a filter is used to sharpen or for edge enhancement
High – Pass Filtering
78
Note that in order to use
this filter, the input image is first changed from a spatial location image into a spatial frequency
image. The filter operates on the frequencies to sharpen the output image
High – Pass Filtering
79
This is referred to as image smoothing
Low – Pass Filtering
80
The output image appears blurred compared to the input image
Low – Pass Filtering
81
In this type of filtering, the output image noise is reduced, and the
image sharpness is compromised
Low – Pass Filtering
82
First, a low-pass filter is used to blur the image and subsequently
subtracts this blurred image from the original image.
Unsharp (Blurred) Masking
83
The result is a sharper image than the original.
Unsharp (Blurred) Masking
84
are mathematical functions that operate on the
| pixels of the image
Digital filters
85
implies ALL the pixels in the input image
| are used to change the value of ONE pixel in the output image
Global Processing Operations
86
These techniques can process images for
edge enhancement, image sharpening, and image
restoration
Global Processing Operations
87
One popular global operation is to use the ___ in filtering images in the frequency domain rather than in the spatial domain
Fourier Transform (FT)
88
it generates the frequency-space
representation of the image which is useful for many applications, including
segmentation, coding, noise removal, and feature classification
Fourier Transform (FT)
89
mapping colors to pixel values
Pseudocoloring
90
These techniques allow the user to change the position or orientation of pixels in the image rather that the
brightness of the pixels
Geometric operations
91
result in the scaling, sizing, rotation, and translation of images, once again, to enhance
diagnosis
Geometric operations
92
are techniques that allow the user to change the appearance of a
digital image displayed on a monitor for viewing and interpretation
Digital image processing
93
These techniques, for
example, allow both the grayscale and the sharpness of the image to be manipulated to
enhance diagnostic interpretation
Digital image processing
94
is now commonly used by all medical imaging professionals who
have the responsibility for assessing image quality and diagnostic interpretation of all images
produced in an examination
Image post-processing
95
Examples of the Digital image processing are on
Point processing operations, Local processing
operations,
Global processing operations
96
Halide can be:
- Chlorine
- Bromine
- Iodine
97
acts as an activator to improve the
| efficiency of PSL
Europium
98
means color
Farbe
99
PSP IP is taken to a CR
reader, and to be scanned
automatically with the use of Helium Neon (HeNe) laser beam
- this process is called
Photo Stimulated Excitation
100
the transition of the electrons from conduction to valence bands or returning to their original state result in an emission of _____ with ___-nanometer wavelengths
bluish-purple lightbluish-purple light,
| 415 nm
101
It is a word that describes how long it takes for a latent image to dissolve
Fading
102
Traditional two-dimensional x-ray detectors are being replaced with photostimulable x-ray storage
phosphors in the form of
image plates
103
the PSL (photostimulable luminescence) decreases by about ___, if the time between exposure and image reading is 8 hours
25%
104
Used to identify, and scale the raw image data obtained when the IP is scanned in the CR reader
Pre-Processing Operation
105
Pre-Processing Operation are also referred to as ______
Acquisition Processing
106
are intended to correct the raw data collected from bad detector elements that would create problems in the proper functioning of the detector
Pre-Processing
107
It also deals with applying corrections to the raw data
Pre-Processing
108
It is where the shading corrections, pattern recognition, and exposure field recognition is done
Pre-Processing
109
used to
| SELECT THE BEST VALUE OF AN IMAGE
Pre-Processing
110
is a data or values of data that is gathered from scanning and then later they will be
combine to create a digital image by choosing the best value of the data
Analog System
111
to improve the image data that suppresses undesired image or SELECT
some image features relevant for further processing
Pre-Processing
112
It is the manipulation of the radiographic image in order to create a qualitative or quantitative data
Post Processing
113
The use of any technique or technology to enhance the original image captured by the photographer
Post Processing
114
To optimize the image contrast and density to enhance diagnostic interpretation of the image
Contrast Enhancement
115
Any method of exaggerating the visible difference between adjacent structures on imaging by administering contrast media/agents
Contrast Enhancement
116
adjust or control the sharpness or detail of an image by adjusting the frequency components of the image
Edge Enhancement
117
is a 2-D isotropic measure of the 2nd spatial derivative of an image
Laplacian
118
leads to enhanced image quality (IQ) of radiographs
Multifrequency Enhancement
119
A commonly used method of digital postprocessing using Laplace segmentation of the image data
Multifrequency Enhancement
120
has been proposed as a method for producing material-specific images
Dual Energy Processing
121
permitting separate examination of bone and soft structures in the chest
Dual Energy Processing
122
improves the detection of certain parts of the anatomy such as detection of the Pulmonary Nodules and Nodule Calcification Compared
Dual Energy Processing
123
provides useful feedback to the radiographer about exposures delivered to the image receptor
Exposure Indicator
124
is a numerical parameter used to monitor the radiation exposure to the IP in CR imaging
Exposure Indicator
125
Exposure Indicator for Fujifilm Medical CR Systems
Sensitivity Number or S-Number
126
Exposure Indicator for Carestream CR Systems
Exposure Index Or EI
127
Exposure Indicator for Agfa Healthcare CR System
Log of Median Values or LgM
128
Exposure Indicator for Konika Minolta Healthcare
Sensitivity Values or S Values
129
S is inversely proportional to the exposure; hence a low exposure will result in a high S number and a high exposure will result in a low S-number
Fujifilm Medical CR Systems (Sensitivity Number or S-Number)
130
represents a linearly proportional estimate of the radiation exposure to the detector.
Carestream CR Systems (Exposure Index Or EI)
131
is related logarithmically to the median of the IP exposure
Agfa Healthcare CR System (Log of Median Values or LgM)
132
S-values is neither direct or proportional. Instead the relationship is inverse.
An S-value above the target range would indicate a under exposure; and an s-value below the target range would indicate an over exposure
Konika Minolta Healthcare (Sensitivity Values or S-Values)
133
200/Exposure to the IP (mR)
S-number
134
log(Exposure in mR) x 1000 + 2000
EI
135
2.2 + log(Exposure in mR)
LgM
136
Matrix size
m x n
137
collects the freed electrons
capacitor
138
Digital image processing operations
```
Image Enhancement,
Image Restoration,
Image Analysis,
Image Synthesis,
Image Compression
```
139
scintillator layer used to convert x-ray photons into light photons
Cesium Iodide,
| Gadolinium Oxysulfide
140
photoconductor layer used to convert x-ray photons into electrical charge
Amorphous Selenium
