Beam Restriction, Grids, Film :: Bushong, 10, 11, 14, 17, Principles
Quiz yourself by thinking what should be in
each of the black spaces below before clicking
on it to display the answer.
Help!
|
|
||||
|---|---|---|---|---|---|
| Remnant x-rays are those that _____ | show 🗑
|
||||
| show | Field size
🗑
|
||||
| show | increase. (Because of more Compton interaction)
🗑
|
||||
| What is the approximate percentage of x-rays that are transmitted through the patient? | show 🗑
|
||||
| At high kVp, most of the x-rays are transmitted through the body [with/without] interaction. | show 🗑
|
||||
| When kVp is increased with a compensating reduction in mAs, what happens to patient dose? | show 🗑
|
||||
| As field size increases, scatter radiation _____ | show 🗑
|
||||
| Scatter radiation reduces image quality by changing what prime factor? | show 🗑
|
||||
| The x-rays that are most useful to the technologist are: -Absorbed in the body; -Attenuated in the body; -Scattered in the body; -Transmitted in the body. | show 🗑
|
||||
| [Compton interaction/Photoelectric interaction/Transmission] causes the most scatter radiation. | show 🗑
|
||||
| Which of the following is not a beam-restricting device? -Cone; -PBL; -Collimator; -Filter | show 🗑
|
||||
| show | Just smaller than the IR; therefore, x-ray field cutoff can occur if the diaphragm is not properly positioned.
🗑
|
||||
| In a light-localizing variable aperture collimator, periodic inspection must occur to ensure that the light-field very closely predicts the x-ray beam size. [True/False] | show 🗑
|
||||
| First-stage shutters on a collimator are designed to _____ | show 🗑
|
||||
| Off-focus radiation is caused by _____ | show 🗑
|
||||
| The field-defining shutters are constructed of [Al/Pb] | show 🗑
|
||||
| show | scatter radiation.
🗑
|
||||
| Grids and beam-restrictors are the two general types of devices that are used to _____ | show 🗑
|
||||
| What does PBL stand for? | show 🗑
|
||||
| show | Higher kVp decreases absorption and lowers contrast. (Less photoelectric absorption means more Compton interaction)
🗑
|
||||
| When tissue is compressed, there is improved contrast resolution because _____ | show 🗑
|
||||
| When a smaller field size is used, what happens to image contrast? | show 🗑
|
||||
| What effect does a restricted beam have on optical density? | show 🗑
|
||||
| show | +/- 2% of SID
🗑
|
||||
| show | h/D; where h= height of Pb strip, and D= Distance between strips.
🗑
|
||||
| The interspace between grid (Pb) strips is occupied by _____ | show 🗑
|
||||
| The primary purpose of a grid is _____ | show 🗑
|
||||
| A higher grid ratio will [increase/decrease] the effect of scatter absorption. | show 🗑
|
||||
| A lower grid ratio will result in _____ latitude with regard to the effects of grid cut-off. | show 🗑
|
||||
| How does introducing a grid affect patient dose? | show 🗑
|
||||
| What does grid frequency refer to? | show 🗑
|
||||
| show | Focused grids contain Pb strips that are not parallel, but are angled to a specific divergence pattern that must be matched to a determined SID. (The divergence of the x-ray beam at an SID of 40" will match the angle of a 40" focused grid.
🗑
|
||||
| What is the main advantage of a Potter-Bucky grid? | show 🗑
|
||||
| What is the formula for the Contrast Improvement Factor (k)? | show 🗑
|
||||
| show | False. mAs should be increased. (~3-4 times)
🗑
|
||||
| show | Off-level grid cut-off is most severe when the CR is angle perpendicular to the direction of the Pb lines in the grid.
🗑
|
||||
| What is the primary advantage of using the Air-Gap technique as opposed to a grid to reduce scatter radiation striking the IR? | show 🗑
|
||||
| What is the OID/SID relationship when using the Air-Gap technique? | show 🗑
|
||||
| show | Will make the grid thicker. (h/D) in order to obtain a higher ratio, h would have to increase if D remained the same.
🗑
|
||||
| show | Overcoat
Emulsion
Adhesion
Base
Adhesion
Emulsion
Overcoat
🗑
|
||||
| show | Light from the intensifying screens. About 1% of the emitted x-rays strike the screen and film; the other 99% of radiation is from the light emitted from those screens.
🗑
|
||||
| What is the recording medium for radiographic film? | show 🗑
|
||||
| The Halides present in the emulsion are Iodide and, more prevalently _____ | show 🗑
|
||||
| When using single emulsion film, how should the film be loaded into the cassette? | show 🗑
|
||||
| Every film has an inherent OD related to the tint of the base and the properties of the processor chemistry called fog. What is the acceptable range of base + fog? | show 🗑
|
||||
| show | 0.25 - 2.5 (near-white to near-black)
🗑
|
||||
| What is "crossover"? | show 🗑
|
||||
| Small, tabular AgBr crystals relate to [high/low] resolution and [fast/slow] speed. | show 🗑
|
||||
| show | Direct exposure film is exposed only from x-rays, and uses no light emitting screens. This results in much higher dose to the patient.
🗑
|
||||
| [True/False] Light emission is one of the many characteristics that should be considered when selecting film. | show 🗑
|
||||
| show | False; high contrast relates to narrow latitude in technique (kVp)
🗑
|
||||
| The difference between fast film and slow film is AgHalide crystal: -Charge; -Concentration; -Shape ;-Size | show 🗑
|
||||
| show | Light-leak exposure, background radiation, Gamma radiation leak, unshielded scatter radiation, heat/humidity.
🗑
|
||||
| show | Red. Rare-earth screens are paired with orthochromatic film which is sensitive to the blue/green side of the light spectrum.
🗑
|
||||
| What are the three types of static artifact on film? | show 🗑
|
||||
| show | Contrast is reduced with the introduction of fog.
🗑
|
||||
| show | True; film is most susceptible to damage before it has been processed.
🗑
|
||||
| show | Dry, low humidity; friction
🗑
|
||||
| show | Humidity between 40% - 60%; Temp < 68 deg F; refrigerated long-term storage; ready-to-use film must be in a light-tight, lead-lined storage bin, stored on-edge, with rotating stock so that older film is used first- before its expiration date.
🗑
|
||||
| show | An imperfection in within a AgHalide crystal that is the catalyst for the transformation of the exposed crystal starting from that point.
🗑
|
Review the information in the table. When you are ready to quiz yourself you can hide individual columns or the entire table. Then you can click on the empty cells to reveal the answer. Try to recall what will be displayed before clicking the empty cell.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
To hide a column, click on the column name.
To hide the entire table, click on the "Hide All" button.
You may also shuffle the rows of the table by clicking on the "Shuffle" button.
Or sort by any of the columns using the down arrow next to any column heading.
If you know all the data on any row, you can temporarily remove it by tapping the trash can to the right of the row.
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
Created by:
ShaneLewis
Popular Radiology sets