Work

Characterization of alternative materials for bolus fabrication in radiotherapy

Year: 2026

Type: article

Abstract: In certain radiotherapy protocols, a more superficial dose distribution is required, necessitating the use of a bolus to ensure adequate dose delivery to the skin and subcutaneous tissues. Although commercially available bolus materials are widely recognized and employed for this purpose, their availability remains limited in many radiotherapy centers across Brazil. This study aimed to evaluate the percentage depth dose (PDD) curve, skin entrance dose, depth of maximum dose, and dose profile to determine the suitability of alternative bolus materials fabricated from gauze and disposable cloth. Dosimetric data were acquired using a 6 MV beam from a linear accelerator, a treatment planning system (TPS), computed tomography (CT), radiochromic film, and an ionization chamber. When compared to the commercial bolus, the disposable cloth bolus demonstrated superior performance relative to gauze, achieving a greater superficial dose increase (0.54 cm vs. 0.24 cm). Both alternative materials increased the skin entrance dose in comparison to treatments without a bolus. However, when benchmarked against the commercial bolus, they exhibited lower efficiency, with reductions of 44% and 29% observed for gauze and disposable cloth, respectively. While alternative bolus materials enhanced surface dose delivery, the reduction in depth of maximum dose remained inferior to that provided by the commercial bolus. In terms of dose profile homogeneity, the disposable cloth bolus outperformed gauze, likely due to its tighter and more uniform weave structure. These findings suggest that the disposable cloth bolus presents a promising alternative for routine clinical application, particularly in settings where standard commercial bolus materials are unavailable.

Source: Radiation Physics and Chemistry

DOI: 10.1016/j.radphyschem.2026.113977

Authors: Hélia B. Barbosa, Mirko S. Alva- Sánchez, Rômulo R. Santos, João Vinícius B. Valença, Maíra T. Yoshizumi

Institution: Universidade Federal de Ciências da Saúde de Porto Alegre

Language: English

Topic: Advanced Radiotherapy Techniques

Subfield: Radiation

Field: Physics and Astronomy

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,530