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THE FACTORS WHICH AFFECT THE EXTERNAL RADIATION DOSE RATE OF PET-CT PATIENTS

  • Cho, Ihn Ho (Department of Nuclear Medicine, Yeungnam University Medical School) ;
  • Kim, Su Jin (Department of Radiologic Technology, Daegu Health College) ;
  • Han, Eun Ok (Korea Academy of Nuclear Safety)
  • Received : 2012.11.27
  • Accepted : 2012.12.17
  • Published : 2012.12.31

Abstract

This study derived measures to reduce exposure doses by identifying factors which affect the external radiation dose rate of patients treated with radiopharmaceuticals for PET-CT tests. The external radiation dose rates were measured on three parts of head, thorax and abdomen at a distance of 50cm from the surface of 60 PET-CT patients. It showed there are changes in factors affecting the external radiation dose rate over time after the administration of F-18 FDG. The external radiation dose rate was lower in the patients with more water intake than those with less water intake before the injection of radiopharmaceuticals at all three points: right after the injection of radiopharmaceuticals (average 4.17 mins), after the pre-PEET-CT urination step (average 77.47 mins), and right after the PET-CT test (average 114.15 mins). The study also found there is a need to increase the amount of water intake before the injection of radiopharmaceuticals in order to maintain a low external radiation dose rate in patients. This strategy is only possible under the assumption that the quality of the video has not changed after conducting this study on the relations between the image and quality. This study also found a need to use radiopharmaceuticals with the minimum amount needed for each patient because F-FDG doses affects the external radiation dose rate at the point right after the injection of radiopharmaceuticals. Urination frequency was the most significant factor to affect the external radiation dose rates at the point right after the PET-CT test and the point after the pre-PET-CT urination step. There is a need to realize the strategy to increase the urination frequency of patients to maintain the external radiation dose rate low (average 77.47 mins) before and after the injection of radiopharmaceuticals. In addition, at this point, there is a need to take advantage of personal strategies because the external radiation dose rate is lower if the fasting time is shorter, the contrast medium is used, and the amount of water intake is increased after the administration of radiopharmaceuticals. Finally this study found the need to be able to generalize these findings through an in-depth research on the factors affecting the external radiation dose rate, which includes radiopharmaceutical dose, urination frequency, the amount of water intake, fasting time and the use of contrast medium.

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References

  1. UNSCEAR. Source and effects of ionization radiation, annex D medical radiation exposure. UNSCEAR 2000 Report Vol. I. 2000.
  2. Lee HS. Exposure dose and changes in blood cells by PET/CT test using 18F-FDG. Department of Radiological Science, Graduate School of Life Sciences, Catholic University of Pusan. 2011.
  3. Lee JK. ICRP publication 105 radiological protection in medicine. 2010.
  4. International Commission on Radiological Protection. The 2007 recommendations of the international commission on radiological protection. Publication 103. 2007.
  5. Ministry of Education, Science and Technology Korea Institute of Nuclear Safety. Technical Standards for Radiation Safety Control in Medical Use. 2012.
  6. Jin GH. A Study on the reliability assurance in PET/CT standardized uptake values. Korea food & Drug Administration. GOVP1200950382. 2008:16.
  7. Lim SM. Standardization of performance evaluation of PET-CT. Korea food & Drug Administration. KIRAMS/CR-D06/2006. 2006:10.