ESTRO 2024 - Abstract Book

S5475

RTT - Patient care, preparation, immobilisation and IGRT verification protocols

ESTRO 2024

For the intrafraction errors analysis, treatment interruptions were recorded 202 times (for both groups) and of those, 48.7% due to a longitudinal movement. The treatment of lung patients is highly influenced by the respiratory motion and this continuous monitoring allows for the treatment to automatically stop once out of defined thresholds.

Conclusion:

As for intrafraction errors, SGRT has a clear benefit as the system allows for continuous monitoring of the patients position without the use of additional ionizing radiation and no major impact in treatment time. SGRT systems can improve positioning accuracy. However, the exact correlation between the patient’s surface and the internal position of the tumor is not exact therefore other imaging techniques, such as CBCT, are still mandatory to ensure a safe treatment delivery. The results suggest that SGRT has no meaningful impact in reducing interfraction error, therefore further research is necessary to determine its advantage. The combination IGRT and SGRT could be considered as standard practice and used in a complementary manner. Overall, SGRT can increase the safety of radiotherapy treatments by preventing unnoticeable errors during treatment delivery.

Keywords: SBRT, SGRT, inter/intrafraction errors

References:

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