RAD 121 Carroll Chap 22-23

The adjustment in radiographic technique to compensate for changes in the SID follows which law:

• the law of Bergonie and Tribondeau

• Ceiszynkski’s law

• the inverse square law

• the square law

In order to eliminate any statistically significant magnification of the heart size during chest radiography, dedicated chest units frequently have the x-ray tube locked into a precisely centered position at inches SID:

• 120

• 96

• 40

• 62

With all other factors unchanged, if SID is decreased, shape distortion in the image will:

• decrease as a direct result

• may be affected indirectly, but is not directly controlled by it

• not change at all

• increase as a direct result

With all other factors unchanged, if SID is reduced, image penumbra will:

• may be affected indirectly, but is not directly controlled by it

• not change at all

• decrease as a direct result

• increase as a direct result

Any change in SID of or greater will require a technique adjustment in order to maintain the level of radiation exposure:

• 50%

• 30%

• 20%

• 10%

With all other factors unchanged, if SID is decreased, magnification in the image will:

• may be affected indirectly, but is not directly controlled by it

• not change at all

• decrease as a direct result

• increase as a direct result

When the SID is changed, to solve for which new mAs setting will maintain exposure to the image receptor, use the:

• magnification formula

• inverse square law

• square law

• 15% rule

With all other factors unchanged, if the OID is increased, overall exposure at the image receptor plate will:

• decrease as a direct result

• increase as a direct result

• not change at all

• may be affected indirectly, but is not directly controlled by it

The SOD/OID ratio is related to the sharpness of detail in the image:

• it is not directly related

• exponentially

• by inverse proportion

• by direct proportion

What are the 3 image qualities affecting SID:

• Exposure level, mAs and magnification

• Magnification, kVp and sharpness

• kVp, SID and sharpness of recorded detail

• Exposure level, magnification and sharpness of recorded detail