What factor contributes to reducing patient dose in digital radiography?

• A. Proper patient positioning and collimation
• B. Increasing exposure factors
• C. Larger field size
• D. Longer exposure time

Answer: (A)

When you limit the area being irradiated and align the beam precisely to the region of interest, patient dose decreases. Proper patient positioning ensures the x-ray beam travels through the anatomy you need with the right geometry, reducing the chance of repeats and avoiding unnecessary exposure to adjacent tissues. Tight collimation shapes the beam to the size of the anatomy, cutting out surrounding tissue and reducing absorbed dose as well as scatter that can degrade image quality. In digital radiography, this targeted approach helps you achieve adequate image quality at lower doses, since you’re not illuminating extra tissue that would require higher exposure or post-processing compensation. Conversely, increasing exposure factors, using a larger field size, or elongating exposure time would raise the dose rather than lower it.