Help
Options
Question
What is the principal difference between screen-film radiology and CR?
click to flip
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't know
Question
The laser light used in CR has a ............. wavelength than the emitted light.
Remaining cards (43)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
CR- Bushong Ch. 15
| Question | Answer |
|---|---|
| What is the principal difference between screen-film radiology and CR? | Analog vs. digital |
| The laser light used in CR has a ............. wavelength than the emitted light. | longer |
| Which of the following can be eliminated during switching from film-screen to CR? a- process image b- reload cassette c- repeat examination d- perform examination | b- reload cassette |
| An electron is described as being metastable: | Has higher energy than it should have |
| Which of the following is most intense? a- Laser light b- normal visual light c- stimulable emission d- x-ray beam | a- laser light (focused/high intensity vs. x-ray that has weak and strong) |
| Which of the following is monochromatic? a- infrared light b- laser light c- stimulated emission d- visible light e- x-ray beam | b- laser light (because its finely focused intense light) |
| PSP image receptors are effective because: | metastable states are produced |
| About how much time can pass between exposing a CR cassette and reading it before image quality declines? | 8 hours |
| As a descriptor of a PSP, the term turbid refers to an appearance that is: | cloudy |
| True/False: PSP image receptors can be fogged by background radiation | true |
| To remove the image of background radiation or a previous image, one should: | Expose the image receptor to intense white light |
| PSP emit light when exposed to: | exposed to x-rays |
| SPS emit light when exposed to: | exposed to light |
| The photostimulable emission in CR has a ............. wavelength than the laser-stimulating light | shorter |
| The slow scan portion of the CR reader is under .............. control | mechanical |
| spacial resolution in CR is principally determined by: | laser beam diameter |
| the source of the stimulating light is: | the laser |
| How does the CR reader maintain the laser beam as a circle? | beam shaping optics |
| Which of the following is NOT a photodetector? a- ADC b- CCD c- CMOS d- PD e- PMT | a- ADC (analog-to-digital converter) |
| The x-ray capture element of a CR imaging plate is the: | BaFBr (barium fluorohalide) |
| The characteristic curve of a CR imaging plate is described as: | Image receptor response function |
| An advantage of CR over screen-film radiography, regardless of the type of examination, is the relatively constant: | image contrast |
| Patient radiation dose reduction in CR is limited by: | system noise |
| Which is less important (kVp or mAs) when CR is compared with screen-film radiography? | kVp- because algorithms in computer can alter contrast to compensate for kVp technique |
| True/False: Fewer repeats is an advantage of CR over screen-film radiography | True: due to technique compensation in the computer |
| CR imaging allows for the display of about how many shades of grey? | 10,000 shades of grey |
| Screen-film radiography allows for the display of about how many shades of grey? | 30 shades of grey |
| What are the 3 main sources of image noise in CR? | Mechanical defects, Optical defects, Computer defects |
| What types of mechanical defects can occur? | slow scan driver and fast scan driver |
| What types of optical defects can occur? | Laser intensity control, scatter of stimulating beam, light quanta emitted by screen, light quanta collected |
| What type of computer defects can occur? | Electronic noise, inadequate sampling, inadequate quantization |
| True/False: CR is a type of digital radiography | True |
| True/False: CR is compatible with film-screen systems | True- can use same table and tube |
| True/False: The imaging plate (IP) does not contain an intensifying screen | True- there is no intensifying screen or film in CR |
| What are the layers of the PSP screen? | Protective, Photostimulable phosphor, Reflective, Base, Backing |
| What is the chemical symbol for the barium florohalide with europium used in the PSP layer? | BaFBr:Eu or BaFI:Eu |
| Why is the light emitted in latent image formation considered a characteristic interaction? | because the color of the light emitted is dependent on the atomic structure of the phosphor and ultimately the binding energy of the outer shell electron |
| The intensity of the x-ray and the intensity of the light phosphor produced have a (direct/indirect) relationship? | direct |
| True/False: Emitted light is monochromatic. | False: it is polychromatic; producing many different wavelengths generally colors within the blue/violet region |
| True/False: Stimulating light is monochromatic. | True: Infrared beam produced by the reader that only produces the color red |
| Infrared light has .......... frequency and ............ wavelength | low frequency and long wavelength |
| Violet light has .......... frequency and ............. wavelength | high frequency and short wavelength |
| Spacial Resolution is inversely proportionate to the: | diameter of laser beam and size of PSP |
| which layer of the PSP plate sends light in a more forward direction when released from the reader? | reflective |
Created by:
rachelreilly
Popular Radiology sets