ESTRO 2024 - Abstract Book

S4026

Physics - Inter-fraction motion management and offline adaptive radiotherapy

ESTRO 2024

However, the maximum offset was in the Lng direction for the wax material, exceeding 10 mm, as illustrated in Figure 1.

Figure 1: Bolus deviation between treated and planned position for twelve patients, divided into wax and 3D printed bolus materials. Top, bolus translations deviations. Middle, bolus rotations deviations. Bottom, bolus HU variations.

Significant differences in variances between the bolus types were observed for Lng (p < 0.01), Pitch (p < 0.01) and Roll, (p < 0.01), as determined by a two-sample F-test with 5% significance level. These differences indicated enlarged variations for wax bolus for Lng direction and enlarged variation for 3D print at Pitch and Roll.

Conclusion:

The volume of the 3D printed bolus were reduced compared to wax, even though the PTV volumes were comparable. In addition, the 3D printed bolus was fabricated more homogeneous than wax. However, there were increased