If an imaging modality must reduce noise, what should the appropriate adjustments be for collimation and mAs?

To address the need for reducing noise in an imaging modality, increasing the mAs (milliamperage-seconds) plays a crucial role. Higher mAs results in more x-ray photons being produced, which contributes to a better signal-to-noise ratio. This increase in signal strength directly correlates with a reduction in image noise, thereby improving the overall image quality.

When collimation is reduced, it permits more radiation to reach the detector area, which can also help enhance the image quality. However, excessive reduction of collimation may lead to higher patient doses and increased scatter radiation. In this context, the adjustments should aim to balance the need for minimizing noise while being mindful of patient safety.

Thus, increasing the mAs to reduce noise, combined with a strategic decrease in collimation, can lead to a clearer image due to the enhanced amount of information captured by the detector while managing scatter effectively. This adjustment facilitates achieving the desired image quality, making option A the appropriate choice for reducing noise in computed tomography.