Which of the following reduce patient radiation dose?

• A. 1 and 2
• B. 1 and 3
• C. 2 and 3
• D. 1, 2 and 3

Answer: (C)

Reducing patient dose comes from limiting what is irradiated and using exposure practices that achieve diagnostic quality with the least radiation. Two of the listed actions actively cut dose: optimizing technique to use the lowest acceptable exposure for the needed image and applying protective measures that reduce exposure to non-target tissues. When these two approaches are used together, the patient’s overall dose decreases without compromising image quality. The remaining action does not contribute to dose reduction, so it wouldn’t be part of an ALARA strategy. In practice, apply tight collimation, use shielding appropriately, optimize exposure factors (often with automatic exposure control), and minimize repeats to keep dose as low as reasonably achievable.