ESTRO 2024 - Abstract Book

S331

Beachytherapy - Physics

ESTRO 2024

Table. Simulated positions of radiation source channel 1 of Venezia22 brachytherapy applicators and its mismatching (B) with library applicator source dwell-positions.

Conclusion:

The possibility of constructing a model of the behaviour of the radiation source inside the applicator during the treatment procedure based on the mechanical features of the afterloader and the applicator is shown.

It was found that the largest discrepancy between the delayed positions of the simulated source and the library position does not exceed 1.5 mm (i.e., does not exceed the stated tolerance value of 2 mm).

However, we do not know how much statistical variation there is in mechanical performance between machines and applicators caused by changes in unpredictable factors such as friction within the applicator or cable stiffness that directly affect the movement of the source within the applicator. Therefore, we cannot predict how often there may be a possible discrepancy between the actual position of the source and its library position more than 2 mm.

At the very least, monitoring the mechanical features discussed can be recommended as one of the tools of a quality control program.

Keywords: dwell-position, quality control, model

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Proffered Paper

expanding calibration service for LDR-Brachytherapy seeds by photon fluence determination