Term
| What is the relationship between wavelength and energy? |
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Definition
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Term
| Gamma rays have relatively _____ energy and _____ wavelength. |
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Definition
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Term
| Which end of the x-ray tube has a filament? |
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Definition
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Term
| Is the cathode or the anode negative? Which direction to electrons travel? |
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Definition
| Cathode; Negative to Positive |
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Term
| What is the purpose of heating the cathode filament? |
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Definition
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Term
| Where do electrons in an x-ray tube eventually strike? |
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Definition
| The tungsten target on the anode |
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Term
| Electrons interact to produce _____. |
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Definition
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Term
| _____ is the # of x-ray photons determined by the heat of the filament that determines the # of e- that cross the gap in the tube. |
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Definition
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Term
| _____ is the energy of the x-ray photons determined by the electrical potential expressed across the gap in the tube that moves the electrons |
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Definition
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Term
| What are milliamperseconds (mAs)? |
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Definition
| # of photons produced (milliamperage & exposure time) |
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Term
| What is kilovoltage (kVp)? |
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Definition
| penetrating ability of the photons |
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Term
| To maintain the same mAs, if one increases the milliamperage, one must _____ the exposure time. |
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Definition
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Term
| To maintain the same exposure quality, if the mAs is reduced by 1/2, how does that affect the kVp? |
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Definition
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Term
| To maintain the same exposure quality, if the mAs is doubled, how does that affect the kVp? |
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Definition
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Term
| To increase exposure, one may _____ the mAs, or _____ the kVp. |
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Definition
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Term
| To decrease exposure, one may _____ the mAs, or _____ the kVp. |
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Definition
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Term
| General radiation is AKA _____. |
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Definition
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Term
| After the release of a photon, what happens to the e-? |
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Definition
| It usually gives up only a portion of its energy & continues to travel in a new direction |
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Term
| How much energy must an e- have to generate characteristic radiation? |
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Definition
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Term
| Is most of the x-ray beam characteristic or general radiation? |
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Definition
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Term
| The cathode filament size partially determines the _____ size of the tube. |
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Definition
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Term
| The actual focal spot is _____ to the target surface. |
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Definition
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Term
| What is the purpose of a rotating anode? |
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Definition
| Provides a larger target surface to dissipate heat resulting in a smaller focal spot |
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Term
| Why should overheating of the x-ray tube be avoided? |
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Definition
| Heat causes injury to the anode, which causes trapping of photons. |
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Term
| What is the function of the collimator? |
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Definition
| Limits the size of the field of primary radiation |
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Term
| _____ @ tube head decreases patient exposure & is a factor in radiation safety. |
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Definition
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Term
| What is the purpose of a grid? |
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Definition
| Limits scatter radiation from reaching the x-ray film |
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Term
| What is a grid composed of? |
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Definition
| Lead foil strips w/ interposed radiolucent strips, covered w/ protective plates |
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Term
| Secondary radiation _____ w/ increase in tissue thickness. |
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Definition
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Term
| A grid should be used w/ _____ tissue thickness. |
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Definition
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Term
| When using a grid, it is necessary to _____ the mAs setting. |
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Definition
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Term
| Where are grids usually located? |
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Definition
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Term
| What does the cassette contain? |
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Definition
| Fluorescent intensifying screens |
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Term
| _____ in intensifying screens provide different speed systems. |
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Definition
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Term
| The _____ the crystal, the better the radiographic detail. |
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Definition
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Term
| With smaller crystal size, the exposure must be _____. |
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Definition
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Term
| T/F: Wavelength of visible light emitted by intensifying screen must be same wavelength as film sensitivity. |
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Definition
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Term
| T/F: Wavelength of visible light emitted by darkroom light must be same wavelength as film sensitivity. |
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Definition
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Term
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Definition
| Photostimulable Phosphor Imaging Plates (used in indirect system) |
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Term
| What happens to the plate in a CR reader? |
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Definition
| Scanned by helium-neon laser |
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Term
| How is residual latent image on a CR plate erased? |
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Definition
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Term
| _____% of latent image is lost within 8 hours. |
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Definition
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Term
| What should be done w/ a CR plate that has not been used for 24 hours? |
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Definition
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Term
| What limits the use of direct DR systems? |
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Definition
| Manufacturing problems, cost, fragility |
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Term
| Fluorescence of intensifying screens --> _____ |
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Definition
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Term
| Outline the 4 steps of the film path in an automatic processor. |
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Definition
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Term
| According to the inverse square law, doubling the distance _____ the radiation; Quadrupling the distance _____ the radiation. |
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Definition
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Term
| Lead gloves absorb _____. |
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Definition
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Term
| T/F: The issue of film/screen combinations is of greater importance w/ the use of equipment w/ a high mA capability. |
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Definition
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Term
| T/F: Digital systems utilize pre-existing x-ray technology. |
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Definition
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Term
| T/F: With CR, cassettes are reusable |
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Definition
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