Prog Med Phys.  2015 Dec;26(4):280-285. 10.14316/pmp.2015.26.4.280.

Evaluation of Fabricated Semiconductor Sensor for Verification of gamma-ray Distribution in Brachytherapy

• Park JE
• Kim KT
• Choi WH
• Lee H
• Cho SJ
• Ahn SH
• Kim JY
• Song YK
• Kim KB
• Huh HD
• Park SK

• KMID: 2151763
• DOI: http://doi.org/10.14316/pmp.2015.26.4.280

Abstract

In radiation therapy fields, a brachytherapy is a treatment that kills lesion of cells by inserting a radioisotope that keeps emitting radiation into the body. We currently verify the consistency of radiation treatment plan and dose distribution through film/screen system (F/S system), provide therapy after checking dose. When we check dose distribution, F/S systems have radiation signal distortion because there is low resolution by penumbra depending on the condition of film developed. In this study, We fabricated a HgI2 Semiconductor radiation sensor for base study in order that we verify the real dose distribution weather it's same as plans or not in brachytherapy. Also, we attempt to evaluate the feasibility of QA system by utilizing and evaluating the sensor to bracytherapy source. As shown in the result of detected signal with various source-to-detector distance (SDD), we quantitatively verified the real range of treatment which is also equivalent to treatment plans because only the low signal estimated as scatters was measured beyond the range of treatment. And the result of experiment that we access reproducibility on the same condition of gamma-ray, we have made sure that the CV (coefficient of variation) is within 1.5 percent so we consider that the HgI2 sensor is available at QA of brachytherapy based on the result.

Keyword

Digital radiation detector; HgI2; gamma-ray Detector; Brachytherapy; Radiation therapy

MeSH Terms

Brachytherapy*
Semiconductors*
Weather

Figure

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  Fig. 1. Structure of material layer (a) and (b) diagram of fabricated sensors.

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  Fig. 2. Experimental setup.

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  Fig. 3. Corrected signals by increased thickness respectively.

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  Fig. 4. Corrected signals by increased distance.

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  Fig. 5. Comparison of film and digital sensor.

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  Fig. 6. Verification of γ-ray distribution by EBT film.

Reference

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