Chapter 8 Exam Flashcards
Which of the following describes the process of radiographic image formation?
a. Beam attenuation
b. Differential absorption
c. Dynamic imaging
d. Ionization
b. Differential absorption
X-rays can eject electrons from atoms. This is known as:
a. Beam attenuation
b. Differential absorption
c. Dynamic imaging
d. Ionization
d. Ionization
The x-ray interaction with anatomic tissue that is responsible for scattering is:
a. Ionization
b. Photoelectric
c. Compton
d. Absorption
c. Compton
Which of the following will increase beam attenuation?
a. Higher kilovoltage
b. Decreasing tissue density
c. Thicker anatomic part
d. Lower atomic number
c. Thicker anatomic part
Factors that decrease x-ray absorption include:
a. Increased tissue density
b. Increased x-ray beam quality
c. Increased tissue thickness
d. Increased atomic number
b. Increased x-ray beam quality
The range of exposure intensities an image receptor can accurately detect defines:
a. Pixel bit depth
b. Dynamic range
c. Ionization
d. Attenuation
b. Dynamic range
Digital image quality is improved with:
a. Larger pixel sizes
b. Smaller pixel bit depths
c. Increased tissue density
d. Larger matrix size
d. Larger matrix size
- Increasing the pixel bit depth will:
a. Decrease scattering
b. Increase contrast resolution
c. Decrease image quality
d. Increase pixel size
b. Increase contrast resolution
What type of imaging system uses an intensifying screen to convert x-rays to visible light?
a. Film-screen
b. Image intensifier
c. Digital
d. Flat-panel detector
a. Film-screen
Film-screen imaging has a wider dynamic range than digital imaging
a. True
b. False
b. False
Dynamic imaging of internal structures can be visualized with a/an:
a. Image intensifier
b. Flat panel detector
c. Film-screen
d. a and b
d. a and b
The process of differential absorption to form an image is the same for digital, film-screen, and fluoroscopy
a. True
b. False
a. True
What device receives the x-rays?
image receptor
What are the “steps” to producing an x-ray image? (after x-ray production)
- Image receptor can accurately detect a wide dynamic range of exposure intensities
- Anatomic areas of widely different attenuation such as soft tissues and bony structures can be more easily visualized because of the wider dynamic range
- Number of bits that determines the amount of precision in digitizing the analog signal and therefore the number of shades of gray that can be displayed in the image
- Determines the shades of gray displayed on the monitor
- Calculated as 2^n
bit depth
A combination of rows and columns, of small, usually square “picture elements” called pixels (how the digital image is displayed)
matrix
The range of exposure intensities an image receptor can accurately detect
wide dynamic range
For a given FOV, increasing the matrix size will _______ the pixel size and _______ image quality
decrease, increase
For a given FOV, decreasing the matrix size will _______ the pixel size and _______ image quality
increases, decrease
The amount of pixels in the image, size of the matrix
Pixel density