Feasibility of Customized Thermoplastic Patient-Specific Helmet Bolus for Scalp Irradiation Using Volumetric-Modulated Arc Therapy Planning.
Technol Cancer Res Treat
; 23: 15330338241241898, 2024.
Article
em En
| MEDLINE
| ID: mdl-38557213
ABSTRACT
Introduction:
In this study, we sought to develop a thermoplastic patient-specific helmet bolus that could deliver a uniform therapeutic dose to the target and minimize the dose to the normal brain during whole-scalp treatment with a humanoid head phantom.Methods:
The bolus material was a commercial thermoplastic used for patient immobilization, and the holes in the netting were filled with melted paraffin. We compared volumetric-modulated arc therapy treatment plans with and without the bolus for quantitative dose distribution analysis. We analyzed the dose distribution in the region of interest to compare dose differences between target and normal organs. For quantitative analysis of treatment dose, OSLD chips were attached at the vertex (VX), posterior occipital (PO), right (RT), and left temporal (LT) locations.Results:
The average dose in the clinical target volume was 6553.8â cGy (99.3%) with bolus and 5874â cGy (89%) without bolus, differing by more than 10% from the prescribed dose (6600â cGy) to the scalp target. For the normal brain, it was 3747.8â cGy (56.8%) with bolus and 5484.6â cGy (83.1%) without bolus. These results show that while the dose to the treatment target decreased, the average dose to the normal brain, which is mostly inside the treatment target, increased by more than 25%. With the bolus, the OSLD measured dose was 102.5 ± 1.2% for VX and 101.5 ± 1.9%, 95.9 ± 1.9%, and 81.8 ± 2.1% for PO, RT, and LT, respectively. In addition, the average dose in the treatment plan was 102%, 101%, 93.6%, and 80.7% for VX, PO, RT, and LT. When no bolus was administered, 59.6 ± 2.4%, 112.6 ± 1.8%, 47.1 ± 1.6%, and 53.1 ± 2.3% were assessed as OSLD doses for VX, PO, RT, and LT, respectively.Conclusion:
This study proposed a method to fabricate patient-specific boluses that are highly reproducible, accessible, and easy to fabricate for radiotherapy to the entire scalp and can effectively spare normal tissue while delivering sufficient surface dose.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Compostos Organotiofosforados
/
Radioterapia de Intensidade Modulada
Limite:
Humans
Idioma:
En
Revista:
Technol Cancer Res Treat
Assunto da revista:
NEOPLASIAS
/
TERAPEUTICA
Ano de publicação:
2024
Tipo de documento:
Article