Measurement of multi-slice computed tomography dose profile with the Dose Magnifying Glass and the MOSkin radiation dosimeter

Abstract

. (2013). Measurement of multislice computed tomography dose profile with the Dose Magnifying Glass and the MOSkin radiation dosimeter. Radiation Measurements, 55 51-55. Measurement of multi-slice computed tomography dose profile with the Dose Magnifying Glass and the MOSkin radiation dosimeter AbstractThis study describes the application of two in-house developed dosimeters, the Dose Magnifying Glass (DMG) and the MOSkin dosimeter at the Centre for Medical Radiation Physics, University of Wollongong, Australia, for the measurement of CT dose profiles for a clinical diagnostic 16-slice MSCT scanner. Two scanner modes were used; axial mode and helical mode, and the effect of varying beam collimation and pitch was studied. With an increase in beam collimation in axial mode and an increase of CT pitch in helical mode, cumulative point dose at scanner isocentre decreased while FWHM increased. There was generally good agreement to within 3% between the acquired dose profiles obtained by the DMG and the film except at dose profile tails, where film over-responded by up to 30% due to its intrinsic depth dose dependence at low doses. AbstractThis study describes the application of two in-house developed dosimeters, the Dose Magnifying Glass (DMG) and the MOSkin dosimeter at the Centre for Medical Radiation Physics, University of Wollongong, Australia, for the measurement of CT dose profiles for a clinical diagnostic 16-slice MSCT scanner. Two scanner modes were used; axial mode and helical mode, and the effect of varying beam collimation and pitch was studied.With an increase in beam collimation in axial mode and an increase of CT pitch in helical mode, cumulative point dose at scanner isocentre decreased while FWHM increased. There was generally good agreement to within 3% between the acquired dose profiles obtained by the DMG and the film except at dose profile tails, where film over-responded by up to 30% due to its intrinsic depth dose dependence at low doses.

Characterization of a MOSkin detector for in vivo skin dose measurements during interventional radiology procedures

“…Previous research reported that the sensitivity of the MOSkin detector for 150 kVp xray beam (effective energy 64.87 keV) was approximately 6.70 mV cGy −1 , which was measured in comparison with EBT2 film. 41 The sensitivity of the MOSkin detector in a megavoltage beam was 2.63 ± 0.01 mV cGy −1 . 42 The higher sensitivity measured at lower beam energy is due to the increasing dominance of photoelectric absorption and consequently, an F.…”

“…The percentage depth-dose response of the MOSkin detector was investigated previously, 41,45 which compared the MOSkin detector response with Markus chamber and Monte Carlo simulations in water. In their reports, the MOSkin detector showed an over-response compared with the Markus chamber measurements, 41 while Monte Carlo simulations showed MOSkin to have good agreement with simulated water response (±3%). 45 In this study, Fig.…”

Assessment of female breast dose for thoracic cone-beam CT using MOSFET dosimeters

“…The physical performance of this dosimeter was well documented in the literature for external beam radiotherapy [27, 28], interventional radiology procedures [22] and diagnostic radiology dosimetry [16, 17]. …”

“…The p-channel MOSFETs (brand named “MOSkin”) together with a portable reader were supplied by the Center of Medical Radiation Physics (CMRP), University of Wollongong, Australia. The physical performance of this dosimeter was well documented in the literature for external beam radiotherapy [ 27 , 28 ], interventional radiology procedures [ 22 ] and diagnostic radiology dosimetry [ 16 , 17 ].…”

<i>In-Vivo</i> Dosimetry Method for Measuring Peak Surface Dose Using Radiochromic Films during Computed Tomography Scanning of the Sinus

“…The use of Gafchromic films has been used by medical physicist in developing countries[14] [15]; as well as in developed ones. Such trend proves that radiochromic films are available, affordable and reliable dosimeters that maybe used worldwide[16].…”