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Image Production
Equipment Operation & Quality Control and Image Acquisition & Evaluation
Question | Answer |
---|---|
What are some examples of digital imaging? | CT, MRI, CR Lange Q&A; pg 259 |
What is the function of the slit camera ? | Measures focal-spot size and Measures spatial resolution Lange Q&A; pg 262 |
What are the characteristics of X-ray photon? | Fluorescent effects on certain phosphors and physiological effect on living tissue Lange Q&A; pg 265 |
What formula is used to calculate the new mAs when the SID changes? | density maintenance formula Lange Q&A; pg 320 |
What are the four types of grids? | stationary, moving, parallel and focused Lange Q&A; pg 329 |
The best way to minimize involuntary motion is through utilizing the (shortest/longest) exposure time. | shortest Lange Q&A; pg 309 |
An increase in OID will (increase or decrease) magnification. | Increase Lange Q&A; pg 301 |
True/False: The alignment of the x-ray tube affects shape distortion. | True Lange Q&A; pg 298 |
What factors affect recorded detail/resolution? | OID, SID, focal spot, patient factors, intensifying screens, motion Lange Q&A; pg 298 |
What occurs when the x-ray tube is angled? | Elongation Lange Q&A; pg 303 |
What are rare earth phosphors? | Gadolinium, lanthanum, yttrium Lange Q&A; pg 311 |
Recorded detail/spatial resolution increases as what factors are altered? | Focal spot size decreases, SID increases, OID (magnification) decreases, motion decreases, (shape) distortion decreases, screen speed decreases Lange Q&A; pg 312 |
The product of millamperes and exposure time. | Milliampere-seconds Lange Q&A; pg 316 |
What does filtration do? | Reduces patient skin dose, minimum 2.5 mm Al equivalent, increases overall average energy of the x-ray beam Lange Q&A; pg 330 |
What is a pixel? | Two dimensional, picture element, measured in XY direction Lange Q&A; pg 355 |
A graphic representation of pixel value distribution. | Histogram Lange Q&A; pg 394 |
What is the film processor system? | Transport system, replenishment system, temperature regulation system, recirculation system, washer system, dryer system Lange Q&A; pg 388 |
What does magnification do to patient dose? | Increases patient dose due to having to increase the mA value. Lange Q&A; pg 482 |
Frequency's unit of measurement. | Hertz Lange Q&A; pg 438 |
What causes a cracked anode? | A single, large, excessive exposure to a cold anode. Lange Q&A; pg 449 |
What is voltage? | potential difference existing between two points Lange Q&A; pg 309 |
What is quality control? | regular measurement and evaluation of radiographic equipment components and their performance Lange Q&A; pg 304 |
What does window level relate to? | brightness Lange Q&A; pg 300 |
What does window width relate to? | Contrast Scale Lange Q&A; pg 300 |
What causes pitting of the focal track? | Repeated, frequent overloading Lange Q&A; pg 280 |
True or False: X-ray tubes have atleast two filaments, one for each focal spot. | True Lange Q&A; pg 453 |
What is the minimum response time of an AEC? | shortest possible exposure time Lange Q&A; pg 280 |
All components of a circuit device located before the primary cold of a high voltage transformer are considered to be? | Primary of low voltage Lange Q&A; pg 289 |
What is the photocathode made of? | Photoemissive alloy Lange Q&A; pg 280 |
This type of radiation comprises 70-90% of the x-ray beam? | Bremsstrahlung radiation Lange Q&A; pg 286 |
What is the relationship between kV and HVL? | As kV increases, HVL increases Lange Q&A; pg 282 |
What are disadvantages of moving grids over stationary grids? | they can prohibit the use of very short exposure times and they can increase patient radiation dose Lange Q&A; pg 286 |
What are the advantages of battery-powered mobile x-ray units? | ability to store a large quantity of energy and to store energy for extended periods of time Lange Q&A; pg 290 |
What principle would an AEC device operate on? | a photomultiplier tube charged by a fluorescent screen and a parallel plate ionization chamber charged by X-ray photons Lange Q&A; pg 290 |
What does the accurate operation of the AEC device depend on? | positioning of the object with respect to the photocell and beam restriction Lange Q&A; pg 294 |
Factors that contribute to film fog include: | The age of the film, excessive exposure to light, and processor chemistry Lange Q&A; pg 199 |
In comparison with 60 kV, 80 kV will | Permit greater exposure latitude and produce more scatter radiation Lange Q&A; pg 203 |
Chemical fog may be attributed to | Excessive developer temperature, oxidized developer, excessive replenishment Lange Q&A; pg 204 |
HVL is affected by the amount of | kVp and beam filtration Lange Q&A; pg 212 |
A decrease from 200 to 100 mA will result in a decrease in what? | Exposure rate and beam intensity Lange Q&A; pg 219 |
X-ray film emulsion is most sensitive to safe-light fog | After exposure Lange Q&A; pg 225 |
What has the greatest effect on radiographic density / brightness? | SID Lange Q&A; pg 225 |
Which of the following are methods used for x-ray film silver reclamation? | Metallic replacement method and electrolytic method Lange Q&A; pg 230 |
X-ray tube failure is generally caused by: | vaporized tungsten on glass envelope Lange Q&A; pg 259 |
Collimators on radiographic equipment must be evaluated how often? | semi-annually Lange Q&A; pg 259 |
What does DQE refer to? | DQE or Detective quantum efficiency refers to how efficient the phosphors are at detecting and interacting with x-ray photons. Lange Q&A; pg 220 |
What steps are involved in indirect image capture systems? | Indirect image systems use a scintillator to convert x-ray photons to light. That light is then picked up by a photodectector and converted to an electrical signal that is transferred to the ADC (analogue-to-digital converter) Lange Q&A; pg 223 |
What is are compensating filters used for? | A compensating filter is used on parts that have differences in density. The filter helps balance the uneven density by adding thickness to the part. Prevents the thin portion from being "burnt out" during exposure Lange Q&A; pg 229 |
What are the developing steps/stages for radiographic film in order? | Developer, Fixer, Wash, and Dryer Lange Q&A; pg 228 |
(T/F) Histograms are unique to their respective body part. | True Lange Q&A; pg 228 |
What is attenuation? | Attenuation is the reduction of x-ray intensity as it passes through matter. Lange Q&A; pg 216 |