[Dosimetric Characteristics of a Real Time Shapeable Tungsten Containing Rubber with Electron Beams]

Area of Science:

• Medical Physics
• Radiation Oncology
• Materials Science

Background:

• Accurate shaping of radiation beams is crucial for effective electron radiotherapy.
• Traditional collimators, such as low melting-point alloy (LMA), require specific manufacturing processes.
• Development of adaptable and real-time shapeable collimators is an area of interest.

Purpose of the Study:

• To investigate the dosimetric properties of a real-time shapeable tungsten-containing rubber (STR) collimator.
• To compare the performance of STR collimators with conventional LMA collimators for electron beams.
• To assess the feasibility of STR as a substitute for LMA in clinical electron radiotherapy.

Main Methods:

• Circular irradiation fields (40 mm diameter) were shaped using STR and LMA on an electron applicator.
• STR was molded using warm water (approx. 70°C).
• Percent depth doses (PDDs) and lateral dose profiles (penumbra, treatment diameter) for 6 and 12 MeV electron beams were measured and compared. STR transmission was also evaluated.

Main Results:

• STR was easily molded and attached to the applicator after heating.
• Dosimetric parameters (PDDs, dmax, d90, d80, penumbra) for STR were nearly identical to LMA for both 6 and 12 MeV electron beams.
• Treatment diameters and STR transmission were comparable to LMA.

Conclusions:

• The real-time shapeable tungsten-containing rubber (STR) collimator exhibits comparable dosimetric characteristics to low melting-point alloy (LMA).
• STR offers advantages in ease of shaping, flexibility, and immediate usability.
• STR presents a viable and effective substitute for LMA in electron radiotherapy applications.