ESTRO 2024 - Abstract Book

S316

Brachytherapy - Head & neck, skin, eye

ESTRO 2024

As seen in Figures 2a and 2b, the introduction of H2-NBs at a concentration of 1% increases DEF by 98% and 94% at the apex of the tumor with a negative quantity of -12% (at 1.5 mm) and -2.8% (at 2 mm) at the base in the simulation and experiments, respectively. Similar results were seen when five different concentrations of H2-NB were injected into the tumor’s MC region. According to Figure 2c, there are no appreciable differences in the dose enhancement of the early interval plaque surface when using different amounts of H2-NB. However, DEF variations become larger at depths of 0.8–1.2 cm, and all concentrations have maxima at around 1.1 cm. DEF is 154, 174, 188, 200, and 310% for hydrogen concentrations of 0.1, 0.3, 0.5, 1, and 4%. According to the data, the distance of 2.7 mm from the plaque surface plays like a watershed. More electrons were formed at closer distances in the water-only medium, but the addition of hydrogen inhibited their formation. However, following this point, electron production rose progressively in the presence of hydrogen and reached its peak at the tumor’s apex. Figure 2d shows the effects of introducing H2-NB in the tumor medium on different parts of the eye.

Conclusion:

H2-NBs were used as electron radiation-sensitive materials in ocular melanoma brachytherapy for the first time in this study. Hydrogen has been used as a therapeutic gas in medical research, but this is the first time it has been used in the form of NBs in combination with beta radiation. The hydrogen atom is the only element with a