Demonstration of 2D dosimetry using Al2O3 optically stimulated luminescence films for therapeutic megavoltage x-ray and ion beams. (November 2017)

• Record Type: Journal Article
• Authors: Ahmed, M.F.; Shrestha, N.; Ahmad, S.; Schnell, E.; Akselrod, M.S.; Yukihara, E.G.
• Is Part Of: Radiation measurements. Volume 106(2017:Nov.)
• Page Start: 315
• Page End: 320
• Publication Date: 2017-11
• Subjects: OSL -- Al2O3:C -- Al2O3:C, Mg -- 2D dosimetry -- Laser scanning -- Radiotherapy; Nuclear emulsions -- Periodicals; Particle tracks (Nuclear physics) -- Periodicals; Thermoluminescence -- Periodicals; Cosmic rays -- Periodicals; Radiation -- Measurement -- Periodicals; Radiometry -- Periodicals; Radiation Monitoring -- Periodicals; Émulsions nucléaires -- Périodiques; Particules (Physique nucléaire) -- Traces -- Périodiques; Thermoluminescence -- Périodiques; Rayonnement cosmique -- Périodiques; Radiométrie -- Périodiques; 539.77
• DOI: 10.1016/j.radmeas.2017.04.010
• Languages: English
• ISSNs: 1350-4487

Abstract

Abstract: This work gives an overview of the performance of a laser-scanning 2D dosimetry system developed for Al2 O3 optically stimulated luminescence dosimetric (OSLD) films, particularly for applications in radiotherapy using external beams. Al2 O3 :C and Al2 O3 :C, Mg OSLD films were irradiated using a 6 MV X-ray beam, a 221 MeV proton and 430 MeV/u 12 C scanned pencil beams, and read using a specially-developed OSL system. The data obtained show that the OSLD films allow 2D dosimetry with sub-millimetric resolution, with approximately linear photon dose response over a wide dynamic range (20 mGy - 3 Gy), no film saturation up to > 76 Gy, and a minimum detectable dose < 1.0 mGy. No field size dependence within the investigated range of 4–15 cm was observed, based on the agreement with ionization chamber within 1%. The image signal-to-noise ratio is higher for Al2 O3 :C, Mg films than for Al2 O3 :C films due to the higher intensity of fast F + -center emission in Al2 O3 :C, Mg films. The results demonstrate that the 2D dosimetry system based on Al2 O3 films may provide a convenient and precise tool in medical dosimetry, with potential application in small field dosimetry. Highlights: Work gives an overview of laser-scanning 2D dosimetry using Al2 O3 OSLD films. OSLD films were irradiated using a 6 MV X-ray beam, a 221 MeV proton and 430 MeV/u 12 C scanned pencil beams. OSLD films allow 2D dosimetry with sub-millimeter resolution. OSLD response to photons and protons is approximately linear over a wide dynamic range. OSL films show no film saturation up to >76 Gy and a minimum detectable dose <1.0 mGy.