Evaluation of GAFCHROMIC EBT2 dosimetry for the low dose range using a flat-bed scanner with the reflection mode

Tatsuhiro Gotanda, Toshizo Katsuda, Takuya Akagawa, Rumi Gotanda, Akihiko Tabuchi, Kenyu Yamamoto, Tadao Kuwano, Hidetoshi Yatake, Koichi Yabunaka, Yoshihiro Takeda

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Recently developed radiochromic films can easily be used to measure absorbed doses because they do not need development processing and indicate a density change that depends on the absorbed dose. However, in GAFCHROMIC EBT2 dosimetry (GAF-EBT2) as a radiochromic film, the precision of the measurement was compromised, because of non-uniformity problems caused by image acquisition using a flat-bed scanner with a transmission mode. The purpose of this study was to improve the precision of the measurement using a flat-bed scanner with a reflection mode at the low absorbed dose dynamic range of GAF-EBT2. The calibration curves of the absorbed dose versus the film density for GAF-EBT2 were provided. X-rays were exposed in the range between ~0 and 120 mGy in increments of about 12 mGy. The results of the method using a flat-bed scanner with the transmission mode were compared with those of the method using the same scanner with the reflection mode. The results should that the determination coefficients (r 2 ) for the straight-line approximation of the calibration curve using the reflection mode were higher than 0.99, and the gradient using the reflection mode was about twice that of the one using the transmission mode. The non-uniformity error that is produced by a flat-bed scanner with the transmission mode setting could be almost eliminated by converting from the transmission mode to the reflection mode. In light of these findings, the method using a flat-bed scanner with the reflection mode (only using uniform white paper) improved the precision of the measurement for the low absorbed dose range.

Original languageEnglish
Pages (from-to)59-63
Number of pages5
JournalAustralasian Physical and Engineering Sciences in Medicine
Volume36
Issue number1
DOIs
Publication statusPublished - Mar 1 2013

    Fingerprint

Keywords

  • Density resolution
  • Flat-bed scanner
  • Radiochromic film
  • Reflection mode
  • Transmission mode

ASJC Scopus subject areas

  • Biophysics
  • Biomedical Engineering
  • Radiology Nuclear Medicine and imaging
  • Physics and Astronomy(all)

Cite this