Application of detectors in computed radiography systems for radiation dosimetry
Article Sidebar
Main Article Content
Abstract
Introduction: Computed radiography (CR) system has rapidly replaced screen-film imaging system in recent years. The imaging plate (IP) which is the detector of CR system. Its potential to store energy proportional to the amount of radiation reaching detector is represented by exposure indicator (EI) values.
Objectives: To measure radiation output from x-ray tube and to investigate the radiation dose measurement capability of IP by calibration with an ionization chamber which is the standard radiation dosimeter.
Materials and Methods: Radiation output from x-ray tube was measured using IP and ionization chamber under the conditions of tube voltages from 50 to 120 kV, tube current-time product from 3.2 to 32 mAs and added filtration from 0 to 0.3 mmCu. All measurements of 80 conditions were acquired in triplicate. The radiation dose in IP was calculated using EI values applying the specified equation EI=1000×log(E/E0)+C.
Results: Radiation dosimetry using IP and equation can estimate the exposure dose in range with limits of 0.1 to 10.3 μC kg-1. This is a smaller range than that of the ionization chamber of 0.2 to 90.5 μC kg-1. Maximum discrepancy of the purposed radiation dosimetry after applied conversion factors was -6.3%, which is within that ±8% recommended by the International Atomic Energy Agency (IAEA) technical reports series number 457.
Conclusion: The imaging plate of CR systems would be applicable to radiation dosimetry in diagnostic radiology.
Bull Chiang Mai Assoc Med Sci 2016; 49(1): 114-122. Doi: 10.14456/jams.2016.1
Article Details
Personal views expressed by the contributors in their articles are not necessarily those of the Journal of Associated Medical Sciences, Faculty of Associated Medical Sciences, Chiang Mai University.
References
2. American Association of Physicists in Medicine. AAPM Report No.116: An exposure indicator for digital radiography. Maryland: AAPM; 2009.
3. National Council on Radiation Protection and Measurements. Quality Assurance for Diagnostic Imaging, NCRP Report No.99. Bethesda: NCRP; 1988.
4. International Commission on Radiological Protection. The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP Publication 103. Oxford: Pergamon Press; 2007.
5. Ariga E, Ito S, Deji S, et al. Determination of half value layers of X-ray equipment using computed radiography imaging plates. Med Phys 2012; 28:71-5.
6. Ariga E, Ito S, Deji S, et al. Development of dosimetry using detectors of diagnostic digital radiography systems. Med Phys 2007; 34:166-74.
7. International Atomic Energy Agency. Dosimetry in Diagnostic Radiology: An International Quality Assurance Manual, Technical Report Series No. 457. Vienna: IAEA; 2007.