Prog Med Phys.  2021 Dec;32(4):159-164. 10.14316/pmp.2021.32.4.159.

Assessing Commercial CLEANBOLUS Based on Silicone for Clinical Use

• Son J
• Jung S
• Park JM
• Choi CH
• Kim Ji

• KMID: 2524163
• DOI: http://doi.org/10.14316/pmp.2021.32.4.159

Abstract

Purpose
We investigated the properties of CLEANBOLUS based on silicone with suitable characteristics for clinical use.
Methods
We evaluated the characteristics of CLEANBOLUS and compared the results with the commercial product (Super-Flex bolus). Also, we conducted physical evaluations, including shore hardness, element composition, and elongation break. Transparency was investigated through the measured absorbance within the visible region (400–700 nm). Also, dosimetric characteristics were investigated with surface dose and beam quality. Finally, the volume of unwanted air gap was investigated based on computed tomography images for breast, chin, and nose using Super-Flex bolus and CELANBOLUS.
Results
CLEANBOLUS showed excellent physical properties for a low shore hardness (000–35) and elongation break (>1,000%). Additionally, it was shown that CLEANBOLUS is more transparent than Super-Flex bolus. Dosimetric results obtained through measurement and calculation have an electron density similar to water in CLEANBOLUS. Finally, CLEANBOLUS showed that the volume of unwanted air gap between the phantom and each bolus is smaller than Super-Flex bolus for breast, chin, and nose.
Conclusions
The physical properties of CLEANBOLUS, including excellent adhesive strength and lower shore hardness, reduce unwanted air gaps and ensure accurate dose distribution. Therefore, it would be an alternative to other boluses, thus improving clinical use efficiency.

Keyword

Bolus; Transparency; Surface dose; Air gap

Figure

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  Fig. 1 Absorbance from 400 nm to 750 nm (a) and pictures showing the transparency of the for Super-Flex bolus and CLEANBOLUS of 5 mm and 10 mm thicknesses under normal room lighting conditions (b).

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  Fig. 2 Unwanted air gap between each bolus and phantom calculated with computed tomography images for nose. (a) Super-Flex bolus. (b) CLEANBOLUS. Pink line means unwanted air gap.

Reference

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