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The Evaluation of Eye Dose and Image Quality According to The New Tube Current Modulation and Shielding Techniques in Brain CT

두부 CT에서 차폐기법과 새로운 관전류변조기법에 따른 눈의 선량과 화질평가

  • Kwon, Soonmu (Department of Radiologic Technology, Daegu Health College) ;
  • Kim, Jungsu (Department of Radio-technology, Wonkwang Health Science University)
  • 권순무 (대구보건대학교 방사선과) ;
  • 김정수 (원광보건대학교 방사선학과)
  • Received : 2015.06.02
  • Accepted : 2015.08.25
  • Published : 2015.06.30

Abstract

The eye of human is a radiation sensitive organ and this organ should be shielded from radiation exposure during brain CT procedures. In the brain CT procedures, bismuth protector using to reduce the radiation exposure dose for eye. But protecting the bismuth always accompanies problem of the image quality reduction including artifact. This study aim is the eye radiation exposure dose and image quality evaluation of the new tube current modulation such as new organ based-tube current modulation, longitudinal-TCM, angular-TCM between shielding scan technique using bismuth and lead glasses. As a result, radiation dose of eye is reduced 25.88% in new OB TCM technique then reference scan technique and SNR new OB TCM is 6.05 higher than bismuth shielding scan technique and lower than reference scan technique. In clinical brain CT, new OB TCM technique will contribute to reduction of radiation dose for eye without decrease of image quality.

두부 CT 검사에서 눈의 수정체는 높은 방사선 감수성으로 보호되어야 할 장기 중에 하나이다. 두부 CT 검사에서 눈의 피폭선량감소 목적으로 사용되는 비스무스 차폐체는 현저한 선량 감소 효과가 있지만 화질저하의 문제점이 있다. 본 연구는 인체팬텀을 이용한 두부 CT 검사에서 피폭 선량을 줄이기 위해 사용되는 관전류변조기법인 new organ based-tube current modulation, longitudinal-TCM, angular-TCM과 차폐기법인 비스무스, 납 안경을 사용하여 눈의 선량과 화질의 변화 정도를 평가하였다. 연구결과, new OB-TCM에서 눈의 선량은 25.88% 감소되었으며 비스무스를 사용한 검사와 비교하여 CT number, 노이즈, SNR의 변화가 작은 것을 확인하였다. 따라서 new OB-TCM을 임상의 두부 CT 검사에 적용할 경우, 눈의 피폭선량을 감소시키면서 영상의 화질 저하를 방지할 수 있을 것으로 기대된다.

Keywords

References

  1. Yu, Lifeng, et al. "Radiation dose reduction in computed tomography: techniques and future perspective." Imaging in medicine, 1.1, pp. 65-84, 2009. https://doi.org/10.2217/iim.09.5
  2. Xia, W., et al. "CT angiography of the neck: Value of contrast medium dose reduction with low tube voltage and high tube current in a 64-detector row CT." Clinical radiology, 69.4, pp. e183-e189. 2014. https://doi.org/10.1016/j.crad.2013.12.001
  3. Payne, J. T. CT radiation dose and image quality. Radiologic clinics of North America, 43(6), 953-962. 2005. https://doi.org/10.1016/j.rcl.2005.07.002
  4. Brenner, David J., and Carl D. Elliston. "Estimated Radiation Risks Potentially Associated with Full-Body CT Screening 1." Radiology, 232. 3 pp. 735-738, 2004. https://doi.org/10.1148/radiol.2323031095
  5. Smith-Bindman, Rebecca, et al. "Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer." Archives of internal medicine, 169. 22, pp. 2078-2086, 2009. https://doi.org/10.1001/archinternmed.2009.427
  6. Nishizawa K, Maruyama T, Takayama M, Okada M, Hachiya J, Furuya Y. "Determinations of organ doses and effective dose equivalents from computed tomographic examination." Br J Radiol., 64, pp. 20-28, 1991. https://doi.org/10.1259/0007-1285-64-757-20
  7. Maclennan AC, Hadley DM. "Radiation dose to the lens from computed tomography scanning in a neuroradiology department." Br J Radiol., pp. 68:19-22, 1995. https://doi.org/10.1259/0007-1285-68-805-19
  8. Henk, J. M., et al. "Radiation dose to the lens and cataract formation." International Journal of Radiation Oncology Biology Physics, 25.5, pp. 815-82, 1993. https://doi.org/10.1016/0360-3016(93)90310-R
  9. Hopper, Kenneth D., et al. "Radioprotection to the eye during CT scanning." American journal of neuroradiology, 22.6, pp. 1194-1198, 2001.
  10. Kalra MK, Maher MM, Toth TL, Hamberg LM, Blake MA, Shepard JA, et al. "Strategies for CT radiation dose optimization." Radiology, 230, pp. 619-62, 2004. https://doi.org/10.1148/radiol.2303021726
  11. Goo, Hyun Woo. "CT radiation dose optimization and estimation: an update for radiologists." Korean Journal of Radiology., 13.1, 1-11, 2012. https://doi.org/10.3348/kjr.2012.13.1.1
  12. McCollough, Cynthia H., Michael R. Bruesewitz, and James M. Kofler Jr. "CT Dose Reduction and Dose Management Tools: Overview of Available Options 1." Radiographics, 26.2, pp. 503-512, 2006. https://doi.org/10.1148/rg.262055138
  13. Matsubara, Kosuke, et al. "Assessment of an organ-based tube current modulation in thoracic computed tomography." Journal of Applied Clinical Medical Physics, 13.2, 2012.
  14. Organ dose modulation whitepaper, GE Healthcare 3000 N. Grandview Blvd. Waukesha, WI 53188 U.S.A. www.gehealthcare.com
  15. Lai, N. K., et al. "Off-centre effect on dose reduction to anterior surfaces with organ-based tube-current modulation." Radiation Measurements, 59, pp. 155-159, 2013. https://doi.org/10.1016/j.radmeas.2013.04.023
  16. S. Kudomi, F. Yurino, A. Hashimoto, T. Yonezawa, C. Tanaka, Y. Ueda, K. Ueda; Ube/JP, "Usefulness of organ-based tube-current modulation with the orbital synchronized helical scan technique for subtraction 3D CT angiography." European society radiology. 10.1594/ecr2014/C-1356, 2014.
  17. Hopper, Kenneth D., et al. "The breast: in-plane x-ray protection during diagnostic thoracic CT--shielding with bismuth radioprotective garments." Radiology, 205.3, pp. 853-858, 1997. https://doi.org/10.1148/radiology.205.3.9393547
  18. Mukundan Jr, Srinivasan, et al. "MOSFET dosimetry for radiation dose assessment of bismuth shielding of the eye in children." American Journal of Roentgenology, 188.6, pp. 1648-1650, 2007. https://doi.org/10.2214/AJR.06.1146
  19. Hohl, C., et al. "Radiation dose reduction to breast and thyroid during MDCT: effectiveness of an in-plane bismuth shield." Acta Radiologica, 47.6, pp. 562-567, 2006. https://doi.org/10.1080/02841850600702150
  20. Fricke, Bradley L., et al. "In-plane bismuth breast shields for pediatric CT: effects on radiation dose and image quality using experimental and clinical data." American Journal of Roentgenology, 180.2, pp. 407-411, 2003. https://doi.org/10.2214/ajr.180.2.1800407
  21. Leswick, David A., et al. "Thyroid Shields versus z-Axis Automatic Tube Current Modulation for Dose Reduction at Neck CT 1." Radiology, 249.2, pp. 572-580, 2008. https://doi.org/10.1148/radiol.2492071430
  22. Chodick, Gabriel, et al. "Risk of cataract after exposure to low doses of ionizing radiation: a 20-year prospective cohort study among US radiologic technologists." American journal of epidemiology, 168.6, pp. 620-631, 2008. https://doi.org/10.1093/aje/kwn171
  23. Statement approved by AAPM Board of Directors, Feb 2012 - Policy Date: 02/07/2012 Full list of AAPM Policies: http://www.aapm.org/org/policies/
  24. Wang, Jia, et al. "Bismuth shielding, organ-based tube current modulation, and global reduction of tube current for dose reduction to the eye at head CT." Radiology, 262.1, pp. 191-198, 2012. https://doi.org/10.1148/radiol.11110470
  25. Reimann, Anja Judith, et al. "Organ-based computed tomographic (CT) radiation dose reduction to the lenses: impact on image quality for CT of the head." Journal of computer assisted tomography, 36.3, pp. 334-338, 2012. https://doi.org/10.1097/RCT.0b013e318251ec61
  26. Raissaki, Maria, et al. "Eye-lens bismuth shielding in paediatric head CT: artefact evaluation and reduction." Pediatric radiology 40.11, pp. 1748-1754, 2010. https://doi.org/10.1007/s00247-010-1715-6
  27. Hwang IC, Shin WJ, Kang EB, "A Comparative Study on the Lens Dose According to the Change of Shielding Material Used in Brain Computed Tomography", Journal of the Korea radiological society, Vol.9 no.1, pp. 31-37, 2015. https://doi.org/10.7742/jksr.2015.9.1.31
  28. Duan, Xinhui, et al. "Dose reduction to anterior surfaces with organ-based tube-current modulation: evaluation of performance in a phantom study." American Journal of Roentgenology, 197.3, pp. 689-695, 2011. https://doi.org/10.2214/AJR.10.6061

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