Feasibility study of a simple approximation algorithm for in-vivo dose reconstruction by using the transit dose measured using an EPID

Ui Jung Hwang, Mi Hee Song, Tae Seong Baek, Eun Ji Chung, Myonggeun Yoon

Research output: Contribution to journalArticle

Abstract

The purpose of this study is to verify the accuracy of the dose delivered to the patient during intensity-modulated radiation therapy (IMRT) by using in-vivo dosimetry and to avoid accidental exposure to healthy tissues and organs close to tumors. The in-vivo dose was reconstructed by back projection of the transit dose with a simple approximation that considered only the percent depth dose and inverse square law. While the average gamma index for comparisons of dose distributions between the calculated dose map and the film measurement was less than the one for 96.3% of all pixels with the homogeneous phantom, the passing rate was reduced to 92.8% with the inhomogeneous phantom, suggesting that the reduction was apparently due to the inaccuracy of the reconstruction algorithm for inhomogeneity. The proposed method of calculating the dose inside a phantom was of comparable or better accuracy than the treatment planning system, suggesting that it can be used to verify the accuracy of the dose delivered to the patient during treatment.

Original languageEnglish
Pages (from-to)694-699
Number of pages6
JournalJournal of the Korean Physical Society
Volume66
Issue number4
DOIs
Publication statusPublished - 2015

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transit
dosage
approximation
organs
dosimeters
planning
radiation therapy
inhomogeneity
tumors
projection
pixels

Keywords

  • Back projection
  • EPID
  • Intensity modulated radiation therapy
  • Transit dose

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Feasibility study of a simple approximation algorithm for in-vivo dose reconstruction by using the transit dose measured using an EPID. / Hwang, Ui Jung; Song, Mi Hee; Baek, Tae Seong; Chung, Eun Ji; Yoon, Myonggeun.

In: Journal of the Korean Physical Society, Vol. 66, No. 4, 2015, p. 694-699.

Research output: Contribution to journalArticle

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