For obese patients, which combination of techniques is recommended to improve diagnostic image quality while considering dose?

• A. Use a grid and increase technical factors
• B. Do not use a grid and decrease exposure factors
• C. Use a grid and decrease technical factors
• D. Avoid any grid and keep factors constant

Answer: (A)

In imaging obese patients, you must boost image quality by reducing scatter and ensuring enough X‑rays reach the detector despite thick tissue. A grid helps here by absorbing much of the scattered radiation before it reaches the image receptor, which improves image contrast—crucial when the body is large and scatter would otherwise blur detail. However, a grid also blocks some of the primary photons, so you need to raise exposure factors to keep the image adequately dense. In practice, this means increasing techniques (like mA·s, and sometimes adjusting kVp within technique guidelines) to maintain diagnostic receptor exposure while still benefiting from the grid’s scatter reduction. Other options fail because not using a grid allows more scatter to degrade contrast, or using a grid with lower exposure underexposes the image, or keeping factors constant won’t compensate for the increased attenuation in an obese patient. So the best approach is to use a grid and increase technical factors.