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chapter 7,8,9,10
week 4
| Question | Answer |
|---|---|
| What is Distortion | A variation in the size or shape of the image as compared with the subject it represents. |
| Can we eliminate distortion? | No, not completely. Every image has some distortion, every object has some size and shape distortion. |
| What effects size distortion? | 1. SID 2. OID |
| What is shape Distortion? | Unequal Magnification of the actual shape of the structure being examined. |
| What are the prime factors of radiographic exposure? | mA, exposure time, kVp, SID |
| The unit used to indicate the total quantity of X-rays in an exposure. | mAs |
| What is the formula for determining mAs? | mA x Time(seconds)= mAs |
| Name the factors that will result in increased radiographic density. | Increased mA, Increased exposure time, and increased kVp |
| Define Radiographic Density. | The overall blackness or darkness of the radiograph. |
| Density is primarily controlled by varying what? | mAs |
| Define Radiographic Contrast. | The difference in density between adjacent portions of the image |
| Contrast is primarily controlled by altering what? | kilovoltage |
| What is the definition of radiographic fog? | Generalized unwanted exposure on the image. |
| What is another name for size distortion? | Magnification |
| If a radiographic image appears blurred, due to motion, which exposure factor should be used to correct the problem? | Decrease in exposure time (seconds) |
| What is the effect of magnification on recorded detail? | Magnification DECREASES recorded detail. |
| When there is a significant OID that can not be minimized by positioning, what can be done to improve image quality? | Increase the SID |
| The distance between the subject, or part, and the IR is referred to as what? | OID |