Which is cited as the largest contribution to unnecessary patient radiation dose?

• A. Failure To Communicate
• B. Failure To Collimate
• C. Excessive kVp
• D. Excessive mAs

Answer: (B)

Limiting the radiation to only the area of clinical interest is the most effective way to reduce unnecessary patient dose. When the beam is not properly collimated, a larger volume of tissue is exposed, which directly increases the total dose the patient receives and also produces more scatter. That scatter can degrade image quality and may lead to a need for higher exposure settings or repeat imaging, further increasing dose. While high kVp or high mAs can raise dose and should be used judiciously for image quality, the primary way to minimize unnecessary exposure across the patient is to tightly collimated the beam to the anatomy of interest.