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Optimum wavelength of ultraviolet rays in gafchromic EBT2
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Abstracts / Physica Medica 32 (2016) 284–339
Conclusion. It has been observed that the prototype Optical parallel beam scanner is reliable the perspective of resolution for scanning gels for radiotherapy applications. The cost of fabrication scanner is lower than the commercial models. This scanner is a laboratory dedicated level Optical Computed Tomography of course it can be improved and develop in future. http://dx.doi.org/10.1016/j.ejmp.2016.07.101
OPTIMUM WAVELENGTH OF ULTRAVIOLET RAYS IN GAFCHROMIC EBT2 T. Katsuda a,*, R. Gotanda b, T. Gotanda c, T. Akagawa d, N. Tanki e, T. Kuwano f, A. Noguchi g, K. Yabunaka h a
Faculty of Human Relation, Tokai Gakuin University, Gifu 504-8511, Japan b Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki 300-0394, Japan c Faculty of Health Sciences, Junshin Gakuen University, Fukuoka 8158510, Japan d Department of Radiological Technology, Tokushima Red Cross Hospital, Tokushima 773-8502, Japan e Center for life science technologies, RIKEN, Hyogo 650-0047, Japan f Graduate School of Health Sciences, Okayama University, Okayama 700-8558, Japan g Faculty of Health Sciences, Osaka Butsuryo College, Osaka 593-8328, Japan h Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan ⇑ Corresponding author. Introduction. Gafchromic films have been used for the measurement of X-ray dose in diagnostic radiology. UV-A ray can be used as a substitute for X-rays in the double exposure technique to compensate for nonuniformity error of Gafchromic EBT2. Purpose. When using a UV-A light emitting diode (UV-A LED), it is necessary to determine the optimal UV-A wavelength to react with the active layer of Gafchromic EBT2. Therefore, changes in the optical density of Gafchromic EBT2 induced by UV-A were investigated by irradiating it at various wavelengths with UV-A LED. Materials and methods. At first, Gafchromic EBT2 was preirradiated using a uniform UV-A by using fluorescent lamp for 60 min from a distance of 72 cm to reduce nonuniformity error. Second, Gafchromic EBT2 was irradiated for 60 min from a distance of 5.3 cm using a UV-A LED at a wavelength of 353–410 nm. The maximum, minimum, and mean ± standard deviation of pixel values of the subtraction images were evaluated using 0.5 inch of circular region of interest (ROI). The most sensitive wavelength of UV ray was decided. In addition, UV strength was measured in each UV-A LED. Results. When a UV-A LED wavelength of 375 nm was used, the mean ± SD of pixel value of Gafchromic EBT2 was indicated highly pixel value. It was 8915.25 ± 608.86. A 375 nm wavelength UV-A was most effective and sensitive for Gafchromic EBT2. Conclusion. The 375 nm wavelength of UV-A is available as a substitute for X-rays in the double exposure technique. Disclosure. Research supported by JSPS KAKENHI Grant Number 26460740. http://dx.doi.org/10.1016/j.ejmp.2016.07.102
RADIATION DOSE ASSESSMENT OF RADIOSENSITIVE ORGANS USING MOSFET DETECTORS AND MONTE-CARLO BASED DOSIMETRY SOFTWARE PCXMC DURING DENTAL CONE BEAM COMPUTED TOMOGRAPHY EXAMINATIONS Khaled Soliman, Salman Altimyat *, Mousa Bakkari Medical Physics Department, Prince Sultan Military Medical City, Riyadh, Saudi Arabia ⇑ Corresponding author. Introduction. Dental cone beam computed tomography is a new imaging modality increasingly being used in the oral and maxillofacial radiology, mainly for implant planning and assessment of general bony and dental pathological conditions. European Commission, Radiation Protection No 172, Cone beam CT for dental and maxillofacial radiology, 2012 report mentions; that Medical Physicists are required to routinely monitor radiation doses from such modality. Purpose. We propose to establish an easily implemented method to assess the radiation dose delivered to the radiosensitive organs during imaging. Materials and methods. The MOSFET detectors were used to measure the patient eye and thyroid gland radiation doses by placing them directly over the area covering the mentioned organs of the anthropomorphic adult female phantom. The measured doses were compared with the calculated doses using PCXMC software (version 2.0). Results. Absorbed doses in (mGy) to the skin in the region of the eyes and thyroid were measured. MOSFET detectors calibration factor was obtained by direct comparison with calibrated standard ionization chamber. The uncertainty factor was 15% for the kV range used by the scanner. The most common DCBCT examination is the full arch high resolution scan conducted at our hospital using the WhiteFox CBCT scanner. The average measured eye and thyroid doses were 4.3 and 1.2 mGy respectively. The obtained results seem to agree with other published dosimetric studies. Conclusion. The presented method can be used to routinely monitor radiation doses delivered to radiosensitive organs as result of imaging studies using DCBCT scanners in clinical environment. Disclosure. we have nothing to disclose in relation with the presented work. http://dx.doi.org/10.1016/j.ejmp.2016.07.103
X-RAY RESPONSE OF A DIGITAL DETECTOR FOR DENTAL RADIOGRAPHS N. Kalyvas a,b,*, P. Maragkaki b, A. Bakas a,c, G. Fountos a,b, V. Koukou a, N. Martini a, C. Michail a,b, I. Valais a,b, I. Kandarakis a,b a
Laboratory of Radiation Physics Materials Technology and Biomedical Imaging, Faculty of Technological Applications, Technological Educational Institute of Athens, Greece b Department of Biomedical Engineering, Technological Educational Institute of Athens, Greece c Department of Medical Radiologic Technologists, Technological Educational Institute of Athens, Greece ⇑ Corresponding author. Introduction. Current dental imaging technology offers indirect detectors capable of digital imaging. These detectors incorporate a scintillator coupled to a photoreceptor.
Abstracts / Physica Medica 32 (2016) 284–339
Conclusion. It has been observed that the prototype Optical parallel beam scanner is reliable the perspective of resolution for scanning gels for radiotherapy applications. The cost of fabrication scanner is lower than the commercial models. This scanner is a laboratory dedicated level Optical Computed Tomography of course it can be improved and develop in future. http://dx.doi.org/10.1016/j.ejmp.2016.07.101
OPTIMUM WAVELENGTH OF ULTRAVIOLET RAYS IN GAFCHROMIC EBT2 T. Katsuda a,*, R. Gotanda b, T. Gotanda c, T. Akagawa d, N. Tanki e, T. Kuwano f, A. Noguchi g, K. Yabunaka h a
Faculty of Human Relation, Tokai Gakuin University, Gifu 504-8511, Japan b Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki 300-0394, Japan c Faculty of Health Sciences, Junshin Gakuen University, Fukuoka 8158510, Japan d Department of Radiological Technology, Tokushima Red Cross Hospital, Tokushima 773-8502, Japan e Center for life science technologies, RIKEN, Hyogo 650-0047, Japan f Graduate School of Health Sciences, Okayama University, Okayama 700-8558, Japan g Faculty of Health Sciences, Osaka Butsuryo College, Osaka 593-8328, Japan h Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan ⇑ Corresponding author. Introduction. Gafchromic films have been used for the measurement of X-ray dose in diagnostic radiology. UV-A ray can be used as a substitute for X-rays in the double exposure technique to compensate for nonuniformity error of Gafchromic EBT2. Purpose. When using a UV-A light emitting diode (UV-A LED), it is necessary to determine the optimal UV-A wavelength to react with the active layer of Gafchromic EBT2. Therefore, changes in the optical density of Gafchromic EBT2 induced by UV-A were investigated by irradiating it at various wavelengths with UV-A LED. Materials and methods. At first, Gafchromic EBT2 was preirradiated using a uniform UV-A by using fluorescent lamp for 60 min from a distance of 72 cm to reduce nonuniformity error. Second, Gafchromic EBT2 was irradiated for 60 min from a distance of 5.3 cm using a UV-A LED at a wavelength of 353–410 nm. The maximum, minimum, and mean ± standard deviation of pixel values of the subtraction images were evaluated using 0.5 inch of circular region of interest (ROI). The most sensitive wavelength of UV ray was decided. In addition, UV strength was measured in each UV-A LED. Results. When a UV-A LED wavelength of 375 nm was used, the mean ± SD of pixel value of Gafchromic EBT2 was indicated highly pixel value. It was 8915.25 ± 608.86. A 375 nm wavelength UV-A was most effective and sensitive for Gafchromic EBT2. Conclusion. The 375 nm wavelength of UV-A is available as a substitute for X-rays in the double exposure technique. Disclosure. Research supported by JSPS KAKENHI Grant Number 26460740. http://dx.doi.org/10.1016/j.ejmp.2016.07.102
RADIATION DOSE ASSESSMENT OF RADIOSENSITIVE ORGANS USING MOSFET DETECTORS AND MONTE-CARLO BASED DOSIMETRY SOFTWARE PCXMC DURING DENTAL CONE BEAM COMPUTED TOMOGRAPHY EXAMINATIONS Khaled Soliman, Salman Altimyat *, Mousa Bakkari Medical Physics Department, Prince Sultan Military Medical City, Riyadh, Saudi Arabia ⇑ Corresponding author. Introduction. Dental cone beam computed tomography is a new imaging modality increasingly being used in the oral and maxillofacial radiology, mainly for implant planning and assessment of general bony and dental pathological conditions. European Commission, Radiation Protection No 172, Cone beam CT for dental and maxillofacial radiology, 2012 report mentions; that Medical Physicists are required to routinely monitor radiation doses from such modality. Purpose. We propose to establish an easily implemented method to assess the radiation dose delivered to the radiosensitive organs during imaging. Materials and methods. The MOSFET detectors were used to measure the patient eye and thyroid gland radiation doses by placing them directly over the area covering the mentioned organs of the anthropomorphic adult female phantom. The measured doses were compared with the calculated doses using PCXMC software (version 2.0). Results. Absorbed doses in (mGy) to the skin in the region of the eyes and thyroid were measured. MOSFET detectors calibration factor was obtained by direct comparison with calibrated standard ionization chamber. The uncertainty factor was 15% for the kV range used by the scanner. The most common DCBCT examination is the full arch high resolution scan conducted at our hospital using the WhiteFox CBCT scanner. The average measured eye and thyroid doses were 4.3 and 1.2 mGy respectively. The obtained results seem to agree with other published dosimetric studies. Conclusion. The presented method can be used to routinely monitor radiation doses delivered to radiosensitive organs as result of imaging studies using DCBCT scanners in clinical environment. Disclosure. we have nothing to disclose in relation with the presented work. http://dx.doi.org/10.1016/j.ejmp.2016.07.103
X-RAY RESPONSE OF A DIGITAL DETECTOR FOR DENTAL RADIOGRAPHS N. Kalyvas a,b,*, P. Maragkaki b, A. Bakas a,c, G. Fountos a,b, V. Koukou a, N. Martini a, C. Michail a,b, I. Valais a,b, I. Kandarakis a,b a
Laboratory of Radiation Physics Materials Technology and Biomedical Imaging, Faculty of Technological Applications, Technological Educational Institute of Athens, Greece b Department of Biomedical Engineering, Technological Educational Institute of Athens, Greece c Department of Medical Radiologic Technologists, Technological Educational Institute of Athens, Greece ⇑ Corresponding author. Introduction. Current dental imaging technology offers indirect detectors capable of digital imaging. These detectors incorporate a scintillator coupled to a photoreceptor.