Medical Image Data Flashcards
A digital image is made up a two dimensional array of numbers
Matrix
Matrix consist of columns (M) and rows (N) that define small square region is called?
Picture Element or Pixels
Increase of number of pixel
Resolution: good / high quality
Decrease number of pixels
Resolution: bad / low quality
Increase size of pixel
Resolution: low / bad quality
Decrease size of pixel
Resolution: high / good quality
The amount of body part or patient included in the image
Field of View (FOV)
The larger, more area is imaged
Field of View (FOV)
Is the smallest element in a digital image
Pixels or picture element
Is directly related to the amount of spatial resolution or detail in the image
Pixel Size
1000 or more shades of gray, can adjust to have a good and better result
Digital Imaging
It uses only 30 shades of gray.
Manual Processing or Conventional Xray
The number of bits within the pixels
Pixel Bit Depth
It has 10 to 16 bit depths resulting in more shades of gray
Pixel Bit Depth
Refers to its appearance on the display monitor of the computer
Brightness
Is a function of the monitors ability to emit light through the surface of the display
Brightness
The ability of the digital system to display subtle changes in the shade of gray
Contrast Resolution
The ability of the imaging system to demonstrate small details of an object
Spatial Resolution
Contributes no useful diagnostic information and serves only to detract from the quality of the image
Quantum Noise
Is visible as brightness or density fluctuations on the images
Quantum Noise
The fewer the photons reaching the IR to form the image, the greater is the visible on the digital image
Quantum Noise
Grainy or sandy-like appearance
Image Noise or Quantum Noise
Ability to respond to varying levels of exposure, more tissue densities on the digital image are seen, giving the appearance of more detail.
Dynamic Range
The range of exposure diagnostic image values the image detector is able to produce
Exposure Latitude
Dependent on the image detector the higher dynamic range of the detector, the more values can be detected
Exposure Latitude
Dependent on the image detector the higher dynamic range of the detector, the more values can be detected
Exposure Latitude
Is to generate an image that is more pleasing to the observer
Image Enhancement
Is to improve the quality of images that have distortions or degradation
Image Restoration
Is to reduce the size of the image in order to decrease transmission time and reduce storage space
Image Compression
Creates images from other images or non-image data
Image Synthesis
When the frequencies of areas of interest are known, those frequencies can be amplified and other frequencies suppressed
Spatial Frequency Filtering
EDGE ENHANCEMENT
Edge enhancement are also know as ?
high-pass filtering
Smoothing are also known as?
low-pass filtering
Occurs by averaging each pixels frequency with surrounding pixel values to remove high-frequency noise
Spatial Frequency Filtering
SMOOTHING
The result is a reduction of noise and contrast
Smoothing
The process of adding text to an image
Annotation
Controls how bright or dark the screen image is
Window Level
Controls the ratio of black and white or contrast
Window Width
Blacken out the white collimation borders, effectively eliminating veil glare
Background Removal or Shutering
The portrait, landscape, and rotation
Image Orientation
Zooming in and out
Magnification
Result in a black appearance of bone and a white appearance of soft tissue
Image Inversion
Technique that can remove superimposed structures so that the anatomic area of interest become more visible
Digital Subtraction
When anatomy or the area of interest is too large to fit on one cassette, multiple images can be “stitched” together using specialized software programs
Image Stitching
One of the most commonly used three-dimensional (3D) rendering techniques
Multiplanar Reconstruction (MPR)
Used to visualize vessels
(MIP) Maximum Intensity Projection
Air-filled structures
(Minlp) Minimum Intensity Projection
Similar to MIP but allows the user to assign colors based on the intensity of the tissue so that bone, contrast agent, and organs can be seen in different colors
Volume Rendering Technique (VRT)
The Technique uses a histogram-type graph to differentiate the various structures.
Volume Rendering Technique (VRT)
Using a threshold of pixel intensity values, everything below the threshold will be removed, and everything above will be assigned a color and shown as a 3D object
Shaded Surface Display (SSD)
