How does tube current (mA) affect CT scans?

Increasing the tube current, measured in milliamperes (mA), has a direct and significant effect on the quality of CT images produced. When the mA is increased, more x-ray photons are generated, which enhances the overall image quality. This improved quality arises because a higher number of photons improves the signal-to-noise ratio of the images, making them clearer and allowing for better visualization of anatomical structures and potential pathologies.

However, it is essential to recognize that increasing the mA also leads to a corresponding increase in radiation exposure to the patient. This dual aspect of mA adjustment—better image quality at the cost of higher radiation dose—presents a critical consideration in CT imaging protocols, as operators must balance the need for high-quality images with patient safety concerns regarding radiation exposure.

The other options do not accurately reflect the relationship between mA, image quality, and radiation exposure in CT. Thus, the reason that increasing mA enhances image quality and simultaneously increases radiation exposure makes this answer the most comprehensive and appropriate.