Chapter 14-18 Flashcards
Owl (Chapter 14)
The word computer refers to any general-purpose, stored-program electronic digital computer.
Owl (Chapter 14)
Analog refers to a continuously varying quantity; a digital system uses only two values that vary discretely though coding.
Owl (Chapter 14)
To encode is to translate from ordinary characters to computer-compatible characters—binary digits.
Owl (Chapter 14)
Computer programs are the software of the computer.
Owl (Chapter 14)
The electronic circuitry that does the actual computations and the memory that supports this together are called the process.
Owl (Chapter 14)
Main memory is the working storage of a computer.
Owl (Chapter 14)
Storage is an archival form of memory.
Owl (Chapter 14)
Output hardware consists of devices that translate computer information into a form that humans can understand.
Owl (Chapter 14)
Teleradiology is the transfer of images and patient reports to remote sites.
Owl (Chapter 14)
Input hardware converts data into a form that the computer can use.
Owl (Chapter 15)
In the same way that the photographic effect is not fully understood and continues to be studies, so too the physics of PSL is not fully understood.
Owl (Chapter 15)
With CR, a darkroom is unnecessary.
Owl (Chapter 15)
The diameter of the laser beam affects the spatial resolution of the CR imaging system.
Owl (Chapter 15)
Imaging plates should be used soon after the erase cycle has been completed.
Owl (Chapter 15)
Small laser beam diameter is critical for ensuring high spatial resolution.
Owl (Chapter 15)
Sampling and quantization are the process of analog-to-digital conversion (ADC)
Owl (Chapter 15)
A 14-bit CR image has 16,384 gray levels.
Owl (Chapter 15)
CR should be performed at lower techniques than screen-film radiography.
Owl (Chapter 16)
Digital radiography is more efficient in time, space, and personnel than screen-film radiography.
Owl (Chapter 16)
Csl/CCD is an indirect DR process by which x-rays are converted first to light and then to electric signal.
Owl (Chapter 16)
The CCD has higher sensitivity for radiation and a much wider dynamic range than screen-film image receptors.
Owl (Chapter 16)
Csl/a-Si is an indirect DR process by which x-rays are converted first to light and then to electric signal.
Owl (Chapter 16)
Spatial resolution in DR is pixel limited.
Owl (Chapter 16)
a-Se is a direct DR process by which x-rays are converted to electric signal.
Owl (Chapter 16)
Contrast resolution is more important than resolution for soft tissue radiograpy.
Owl (Chapter 17)
Spatial frequency is expressed in line pair per millimeter (lp/mm).
Owl (Chapter 17)
An imaging system with higher spatial frequency has better spatial resolution.
Owl (Chapter 17)
Spatial resolution in digital imaging is limited by pixel size.
Owl (Chapter 17)
Modulation transfer function can be viewed as the ratio of image to object as a function of spatial frequency.
Owl (Chapter 17)
Imaging system spatial resolution is spatial frequency at 10% MTF.
Owl (Chapter 17)
Dynamic range is the number of gray shades that an imaging system can reproduce.
Owl (Chapter 17)
Postprocessing allows visualization of all shades of gray.
Owl (Chapter 17)
Image noise limits contrast resolution.
Owl (Chapter 17)
Image detail (spatial resolution) is determined by system MTF.
Owl (Chapter 17)
Contrast resolution is limited by noise or SNR.
Owl (Chapter 17)
Spatial resolution in screen film radiography is determined principally by focal spot size.
Owl (Chapter 17)
Contrast resolution is preserved in digital imaging, regardless of dose.
Owl (Chapter 17)
Technique creep should replace dose creep.
Owl (Chapter 17)
Patient dose in DR should be low because of high DQE.
Owl (Chapter 17)
DQE is a measure of x-ray absorption efficiency.
Owl (Chapter 17)
The scatter x-ray beam has lower energy than the primary x-ray beam.
Owl (Chapter 18)
The basic photometric unit is the lumen.
Owl (Chapter 18)
The best viewing of a digital display device is straight on.
Owl (Chapter 18)
AMLCDs are superior to CRT displays.
Owl (Chapter 18)
Spatial resolution improves with the use of high megapixel digital display devices.
Owl (Chapter 18)
Aperture ratio is a measure of image luminance of AMLCDs.
Owl (Chapter 18)
Preprocessing of digital images is largely automatic.
Owl (Chapter 18)
Postprocessing of digital images requires operator manipulation.
Owl (Chapter 18)
PACS improves image interpretation, processing, viewing, storage, and recall.
Owl (Chapter 18)
Clients are interconnected, usually by cable in a building, by telephone or cable television lines among buildings, and by microwave or satellite transmission to remote facilities.
Owl (Chapter 18)
Just the cost of the hospital space to accommodate a film file room may be sufficient of justify PACS.
