How can field uniformity be checked in radiation therapy equipment?

Field uniformity in radiation therapy equipment is primarily assessed by measuring flatness and symmetry of the radiation beam. This process involves using tools and detectors to evaluate how uniformly the dose is distributed across the treatment area. Measuring flatness refers to the uniformity of the dose level across the central axis and peripheral areas of the radiation field, ensuring that there are no significant peaks or dips in dose delivery. Symmetry checks assess how evenly the radiation dose is distributed on either side of the central axis, which is crucial for delivering accurate and effective treatment.

These measurements are essential because non-uniformities can lead to overdoses in some areas while underdosing others, which can significantly affect treatment efficacy and patient safety. Regular checks of flatness and symmetry are part of quality assurance protocols to maintain the accuracy of radiation therapy equipment.

Visual assessments, while useful for quickly spotting obvious issues, do not provide the precise quantitative data necessary for determining field uniformity. Measuring dose delivered is important for treatment verification but does not specifically address how evenly that dose is distributed within the field. Reviewing calibration logs helps ensure that the equipment operates correctly but does not directly measure the uniformity of the radiation field.