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RADT 456 Image Acq
Image Acquisition and Evaluation
Question | Answer |
---|---|
What are visibility factors that affect image quality? | Density/brightness and contrast/gray scale pg. 298 |
What are some factors that affect recorded detail? | OID, SID, focal spot size, patient habitus, intensifying screens, and motion pg. 298 |
Which term refers to misrepresentation of the actual size or shape of the structures imaged? | Distortion pg. 299 |
SID is ____ related to magnification and ____ related to recorded detail. | Inversely, directly pg. 301 |
T/F The use of a small focal spot improves recorded detail, but generates more heat at the anode. | True pg. 308 |
When is quantum mottle most likely to occur? | When using fast screens, low mAs, and high kV factors pg. 313 |
T/F Spatial resolution will be improved using a larger matrix. | True pg. 354 |
When using a grid, ____ photons reach the image receptor, producing a decrease in radiographic ____. | Fewer, density pg. 323 |
What are geometric factors that affect image quality? | Detail/ resolution and distortion pg. 298 |
OID is ____ related to magnification and ____ related to recorded detail. | Directly, inversely pg. 301 |
The type of phosphor, phosphor size, phosphor layer thickness, and the reflective backing all contribute to this? | The speed of intensifying screens pg. 312 |
The use of a grid is recommended for body parts measuring what? | 10cm or larger pg. 323 |
What is the term that describes the amount of blackening on an image? | Density pg. 317 |
Which term defines the height of the lead strips compared with the distance between them? | Grid ratio pg. 326 |
What are 5 common errors when using a focused grid? | Angulation, off-level, off-focus, off-center, and upside-down pg. 324-325 |
What are some examples of additive pathological conditions? | Atelectasis, congestive heart failure, Paget disease, rheumatoid arthritis, and ascites pg. 333 |
____ increases the overall energy of the x-ray beam, but also reduces patient skin dose. | Filtration pg. 330 |
What are two types of AEC? | Ionization chamber and phototimer pg. 351 |
T/F Pixel size is directly related to resolution. | False, inversely pg. 356 |
The abbreviation DQE stands for what? | Detective Quantum Efficiency pg. 358 |
What are some examples of destructive pathological conditions? | Osetomalacia, osteoporosis, emphysema, degenerative arthritis, and pneumoperitoneum pg. 333 |
How many hours can an imaging plate be stored or unused before it should be erased? | 48 hours pg. 361 |
When AEC is not used, computed radiography can use exposure data recognition to compensate for approximately what percent of underexposed images and what percent of overexposed images? | 80% and 500% pg. 364 |
T/F The larger the matrix size, with the FOV unchanged, the better the resolution. | True, because pixel size decreases pg. 365 |
What is the computer system responsible for procedure ordering and scheduling, patient database maintenance, reporting and transcription, and billing? | Radiology Information System (RIS) pg. 366 |
What computer system serves to track patient information such as: admission and discharge, diagnostic and treatment services, pharmaceutical and equipment information, billing information, and employee information? | Hospital Information System (HIS) pg. 366 |
A wire mesh test is used to test for what? | SF contact pg. 371 |
Which of the following will result in the best recorded detail? A. 1.5 mm focal spot B. 1.0 mm focal spot C. 0.6 mm focal spot D. 0.3 mm focal spot | D. 0.3 mm focal spot pg. 371 |
Which x-ray detection system does not have a scintillation component? A. Indirect DR using CCD B. Indirect DR using TFT C. Direct DR D. CR | C. Direct DR pg. 374 |
Boxes of unexposed film should be stored in a cool dry environment, under 70 degrees F, and between what percents of humidity? | 40%-60% pg. 382 |
Which step of the film processing clears the film of the unexposed silver bromide and rehardens the emulsion? | Fixer pg. 386 |
Which step of the film processing is responsible for removing the water from the film and shrinks and dries the emulsion? | Dryer pg. 386 |
Which film processor system keeps solution tanks full and ensures that proper solution concentration is maintained? | Replenishment pg. 390 |
What term describes the graphic representation defining all the grayscale values of a particular image? | Histogram pg. 394 |