Correct collimation can increase image quality due to a decrease in:

• A. Beam hardening
• B. Detector saturation
• C. Scatter radiation
• D. Resolution loss

Answer: (C)

Reducing the beam to the area of interest lowers the amount of tissue that the x-ray passes through, which in turn reduces the amount of scatter produced and reaching the detector. Scatter adds a hazy, low-contrast component to the image, so decreasing scatter improves image contrast and overall quality. Beam hardening, detector saturation, and resolution loss are not primarily driven by collimation—the first is a spectral/filtration issue, the second is about exposure levels, and the third involves geometric factors or detector resolution. Therefore, the improvement in image quality from proper collimation comes from a decrease in scatter radiation.