What is the tolerance for the coincidence of light and radiation field in a medical linear accelerator?

The tolerance for the coincidence of light and radiation fields in a medical linear accelerator is set at 2 mm or 1% of the field length. This standard is established to ensure that the radiation treatment being delivered is accurately aligned with the intended target area, which is critical for maximizing therapeutic effects while minimizing damage to surrounding healthy tissues.

Having this level of tolerance helps maintain high precision in radiotherapy procedures, allowing for better patient safety and treatment efficacy. The 2 mm or 1% of the field length specification accommodates various field sizes while ensuring that the alignment remains acceptable. Maintaining this tolerance helps medical dosimetrists, radiation oncologists, and medical physicists ensure that the prescribed radiation dose is delivered accurately during treatment sessions.

In clinical practice, adherence to such standards is necessary for quality assurance in radiotherapy. This ensures that discrepancies in alignment do not lead to unintended exposure of healthy tissue or underdosage of the tumor, which could jeopardize treatment outcomes.