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Exposure factors of 400 mA, 20 ms, 68 kVp, 400-speed system, at 40-in. SID were used to produce a satisfactory radiographic image. A change to 4 mAs can be best compensated for by which of the following?

A. Increasing the SID to 60 in
B. Decreasing the SID to 20 in
C. Decreasing the speed to 200
D. Increasing the kilovoltage to 78 kVp
Answer: Increasing the kilovoltage to 78 kVp

User Ryebread
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Final answer:

To compensate for a change to 4 mAs in radiographic settings, increasing the kilovoltage peak (kVp) is the most effective method to maintain image quality without changing the image geometry. Safety practices such as using a lead apron and shielding are critical to minimize exposure to non-targeted tissues, aligning with the principle of risk versus benefit in medical imaging.

Step-by-step explanation:

The question pertains to the impact of changing exposure factors in radiographic imaging and how best to compensate for a change to 4 mAs. When the milliampere-seconds (mAs) are reduced, the radiographic density also decreases, necessitating a change to maintain image quality. Options like changing source-to-image distance (SID) and film speed exist, but the most effective way of compensating without altering the overall geometry of the image is to increase the kilovoltage peak (kVp). Higher kVp will result in a higher energy beam that would penetrate better, thus compensating for the lower mAs and preserving image quality.

Concerns with radiation exposure are critical in medical imaging. Using a lead apron and shielding as well as fast films are standard practices to limit exposure to tissue. These measures are part of a broader principle of risk versus benefit, ensuring that the low risk of radiation exposure from diagnostic imaging is justified by the benefit of the diagnosis.

User GuSuku
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