What factors influence the accuracy of the dose computed by the treatment planning system (TPS)?

The accuracy of the dose computed by the treatment planning system (TPS) is significantly influenced by the accuracy of the beam calibration and the dose calculation algorithm. Beam calibration involves ensuring that the radiation output from the treatment machine is measured and adjusted to the correct levels, which is crucial for precise dose delivery. If the calibration is inaccurate, it can lead to erroneous dose calculations, adversely impacting treatment effectiveness.

The dose calculation algorithm used in the TPS is also vital for determining how much radiation will be delivered to the tumor and surrounding tissues based on the patient's anatomy and treatment plan. Algorithms are built on complex physics principles and, if not accurately implemented, can adversely affect the predicted dose distribution. Therefore, the reliability of these algorithms, alongside proper beam calibration, directly determines the TPS's ability to compute accurate doses, ultimately affecting patient treatment outcomes.

While other factors, such as the quality of the treatment machine, the patient’s medical history, and the experience of the medical staff, are important in the overall treatment process, they do not specifically influence the TPS's dose computation accuracy in the same fundamental way as the calibration and algorithm do.