Ex) Article Title, Author, Keywords
Ex) Article Title, Author, Keywords
Korean Journal of Medical Physics 2008; 19(1): 49-55
Published online March 25, 2008
Copyright © Korean Society of Medical Physics.
Chang-Lae Lee*†, Hee-Joung Kim*†, Seong Su Jeon‡, Hyo-Min Cho*†, Sora Nam§, Ji-Young Jung*†, Young-Jin Lee*†, Seung-Jae Lee*, Kyung-Rae Dong∥
이창래*†ㆍ김희중*†ㆍ전성수‡ㆍ조효민*†ㆍ남소라§ㆍ정지영*†ㆍ이영진*†ㆍ이승재*ㆍ동경래∥
This study aims to conduct the comparative analysis of the radiation dose according to before and after the calibration of the ionization chamber used for measuring radiation dose in the MDCT, as well as of CTDIW according to temperature and pressure correction factors in the CT room. A comparative analysis was conducted based on the measured MDCT (GE light speed plus 4 slice, USA) data using head and body CT dosimetric phantom, and Model 2026C electrometer (RADICAL 2026C, USA) calibrated on March 21, 2007. As a result, the CTDIW value which reflected calibration factors, as well as correction factors of temperature and pressure, was found to be the range of 0.479~3.162 mGy in effective radiation dose than the uncorrected values. Also, under the routine abdomen routine CT image acquisition conditions used in reference hospitals, patient effective dose was measured to indicate the difference of the maximum of 0.7 mSv between before and after the application of such factors. These results imply that the calibration of the ion chamber, and the correction of temperature and pressure of the CT room are crucial in measuring and calculating patient effective dose. Thus, to measure patient radiation dose accurately, the detailed information should be made available regarding not only the temperature and pressure of the CT room, but also the humidity and recombination factor, characteristics of X-ray beam quality, exposure conditions, scan region, and so forth.
KeywordsMDCT, Ionization chamber, CTDIW, Calibration, Correction
pISSN 2508-4445
eISSN 2508-4453
Formerly ISSN 1226-5829
Frequency: Quarterly