Measurement of the dose index in a 320 detector row CT scanner
Keywords:
Computed Tomography (TC), Computed Tomography Dose Index (CTDI), radiation thickness, phantomAbstract
The purpose of this article is to show part of the tests realized in the acceptance of the Canon Aquilion One TC, which has 320 rows of detectors that allow make acquisitions with a slice thickness up to 160 mm, very useful in pediatric patient examinations. The common tests of the PECCR are contemplated to be performed on scanners with smaller slice thicknesses, so there are proposed other methods for evaluating CTDI in cases that radiation thickness is greater than the radiation detector used in quality controls. Differences have been observed between the methods of up to 12% in less than 80 mm of thickness cases and up to 20% in the largest thickness. In addition, an evaluation of the new metric “equilibrium dose” is made on the 600 mm long phantom TG200, obtaining results that agree with the bibliography. It is proposed a longitudinal dose profile evaluation method for an axial acquisition with radiochromic.
References
Beister M, Kolditz D, et al. Iterative reconstruction methods in X-ray CT. Phys Med 2012;28:94-108.
Flohr TG, McCollough CH, et al. First performance evaluation of a dual-source CT (DSCT) system. Eur Radiol 2006; 16:256.
Mehta D, Thompson R, et al. Iterative model reconstruction: Simultaneously lowered computed tomography radiation dose and improved image quality. Med Phys Int 2013;02:147-55.
Calzado A, Geleijns J, Tomografía computarizada. Evolución, principios técnicos y aplicaciones. Rev Fis Med 2010; 11(3):163-80.
Sorantin E, Riccabona M, et al. Experience with volumetric (320 rows) pediatric CT. Eur J Radiol 2013;82:1091-7.
Gomà C, Ruiz A, et al. Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging. Med Phys. 2011 Mar;38(3):1473-80.
Kroft LJ, Roelofs JJ, et al. Scan time and patient dose for thoracic imaging in neonates and small children using axial volumetric 320-detector row CT compared to helical 64-, 32-, and 16- detector row CT acquisitions. Pediatr Radiol 2010;41:294-300.
Einstein A, Elliston C,et al. Radiation dose from singleheartbeat coronary CT angiography performed with a 320-detector row volume scanner. Radiology 2010;254 3:698-706.
Seguchi S, Aoyama T, et al. Patient radiation dose in prospectively gated axial CT coronary angiography and retrospectively gated helical technique with a 320-detector row CT scanner. Med Phys 2010;37:5579-85.
Cros M, Geleijns J, et al. Perfusion CT of the brain and liver and of lung tumors: Use of Monte Carlo simulation for patient dose examinations with a cone-beam 320-MDCT scanner. AJR 2016;206:1,129-35.
SEFM-SEPR-SERAM. Protocolo Español de Control de Calidad en Radiodiagnóstico. Ed. 2011.
Dixon RL, Anderson JA, et al. Comprehensive methodology for the evaluation of radiation dose in X-ray computed tomography, Report of AAPM Task Group 111: The Future of CT Dosimetry. AAPM, College Park, MD, 2010.
Li, Zhang, and Liu: Calculations of dose metrics proposed by AAPM TG111. Med. Phys 2013;40(8).
ICRU 87, Radiation Dose and Image-Quality Assessment in Computed Tomography. Journal of the ICRU Volume 12 No 1 2012, Oxford University Press.
International Electrotechnical Commission. Medical Electrical Equipment—Part 2-44 Edition 3, Amendment 1: Particular Requirements for Basic Safety and Essential Performance of X-Ray Equipment for Computed Tomography, IEC-60601-2-44 —Edition 3, Amendment 1; 62B/804/CD, Committee Draft (CD), IEC Geneva (2010).
International Atomic Energy Agency. Status of Computed Tomography: Dosimetry for Wide Cone Beam Scanners. Human Health Series No. 5, IAEA (2011).
Salvadó M, Cros M, et al. Monte Carlo simulation of the dose distribution of ICRP adult reference computational phantoms for acquisitions with a 320 detector-row cone-beam CT scanner. Phy Med 2015;31:452-62.
Geleijns J, Artells MS, et al. Computed tomography dose assessment for a 160 mm wide, 320 detector row, cone beam CT scanner. Phys. Med. Biol 2009; 54 10:3141-59.
Albngali A, Shearer A, et al. CT Output Dose Performance-Conventional Approach Verses the Dose Equilibrium Method. Int J Med Phys Clin Eng Radiat Oncol 2018;7:15-26.
Campelo M, Silva M, et al. CTDI versus New AAPM Metrics to assess Doses in CT: a case study. Braz. J. Rad. Sci 2016; 4(2):15.
Descamps C, Gonzalez M, et al. Measurements of the dose delivered during CT exams using AAPM Task Group Report No. 111. J Appl Clin Med Phys. 2012;13(6):3934.
Mori S, Endo M, et al. Enlarged longitudinal dose profiles in cone-beam CT and the need for modified dosimetry. Med. Phys 2005;32(4):1061-9.
Boone JM. The trouble with CTDI100. Med. Phys 2007;34: 1365-71.
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