How does patient thickness influence technique selection?

• A. Larger patients typically require higher kVp and/or mAs to achieve appropriate receptor exposure, while smaller patients require less to avoid overexposure.
• B. Thickness has no impact on technique.
• C. Thicker patients require lower kVp.
• D. Thicker patients require no changes in mAs.

Answer: (A)

When a patient is thicker, more tissue absorbs and scatters the X-ray beam, so fewer photons reach the detector. To get a proper receptor exposure, you compensate by making the beam more penetrating (higher kVp) and/or by increasing the number of photons produced (higher mAs). That’s why larger patients typically require higher kVp and/or higher mAs, while smaller patients need less exposure to avoid overexposure. It’s a balance, though—raising kVp can reduce image contrast, so technique is adjusted to maintain image quality while controlling dose.