When comparing measured and TPS computed data, what must be done in high dose gradient regions?

In high dose gradient regions, establishing larger margins is crucial for accurately assessing the differences between measured and treatment planning system (TPS) computed data. These areas are characterized by rapid changes in dose distribution, which can significantly impact treatment efficacy and safety.

When working in these regions, small discrepancies between the TPS calculations and actual measured doses can lead to substantial variations in the delivered dose to the target and surrounding healthy tissues. Enlarging the margins helps to account for uncertainties in both the TPS calculations and measurement processes, ensuring that dose delivery remains within acceptable limits and minimizes the risk of delivering inadequate or excessive doses.

By implementing larger margins, dosimetrists can more effectively manage the inherent variability and improve the reliability of the treatment plan, particularly in critical areas where precision is vital. This approach aligns with best practices in radiotherapy, where understanding and correcting for dose discrepancies can enhance patient outcomes.