When measuring doses, why is it important to assess both entrance and exit doses?

Assessing both entrance and exit doses is crucial to ensure accurate dose distribution within the treated area. The entrance dose refers to the radiation dose the patient receives as the beam first enters the body, while the exit dose measures how much radiation exits after passing through the tissue. Understanding this distribution helps medical dosimetrists identify how the dose is being delivered throughout the treatment area and to any surrounding healthy tissues.

Accurate dose distribution is vital in radiation therapy to achieve the desired therapeutic effect while minimizing exposure to healthy structures. It helps in verifying that the prescribed dose aligns with the target zone and remains within acceptable safety limits for adjacent healthy tissues. This assessment can influence treatment planning and modification, ensuring optimal dose delivery and effectiveness.