Document Type: Original Research

Authors

1 Department of Medical Physics, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

2 Department of Radiology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

Abstract

Background: Chest CT is a commonly used examination for the diagnosis of lung diseases, but a breast within the scanned field is nearly never the organ of interest.Objective: The purpose of this study is to compare the female breast and lung doses using split and standard protocols in chest CT scanning.Materials and Methods: The sliced chest and breast female phantoms were used. CT exams were performed using a single-slice (SS)- and a 16 multi-slice (MS)- CT scanner at 100 kVp and 120 kVp. Two different protocols, including standard and split protocols, were selected for scanning. The breast and lung doses were measured using thermo-luminescence dosimeters which were inserted into different layers of the chest and breast phantoms. The differences in breast and lung radiation doses in two protocols were studied in two scanners, analyzed by SPSS software and compared by t-test.Results: Breast dose by split scanning technique reduced 11% and 31% in SS- and MS- CT. Also, the radiation dose of lung tissue in this method decreased 18% and 54% in SS- and MS- CT, respectively. Moreover, there was a significant difference (p< 0.0001) in the breast and lung radiation doses between standard and split scanning protocols.Conclusion: The application of a split scan technique instead of standard protocol has a considerable potential to reduce breast and lung doses in SS- and MS- CT scanners. If split scanning protocol is associated with an optimum kV and MSCT, the maximum dose decline will be provided.

Keywords

  1. Janbabanezhad-Toori A, Shabestani-Monfared A, Deevband M, Abdi R, Nabahati M. Dose Assessment in Computed Tomography Examination and Establishment of Local Diagnostic Reference Levels in Mazandaran, Iran. Journal of Biomedical Physics and Engineering. 2015.
  2. Angel E, Yaghmai N, Jude CM, DeMarco JJ, Cagnon CH, Goldin JG, et al. Dose to radiosensitive organs during routine chest CT: effects of tube current modulation. AJR Am J Roentgenol. 2009;193:1340-5. doi.org/10.2214/AJR.09.2886. PubMed PMID: 19843751. PubMed PMCID: 2954276.
  3. Goo HW. CT radiation dose optimization and estimation: an update for radiologists. Korean J Radiol. 2012;13:1-11. doi.org/10.3348/kjr.2012.13.1.1. PubMed PMID: 22247630. PubMed PMCID: 3253393.
  4. Pantos I, Thalassinou S, Argentos S, Kelekis NL, Panayiotakis G, Efstathopoulos EP. Adult patient radiation doses from non-cardiac CT examinations: a review of published results. Br J Radiol. 2011;84:293-303. doi.org/10.1259/bjr/69070614. PubMed PMID: 21266399. PubMed PMCID: 3473464.
  5. Kim YK, Sung YM, Choi JH, Kim EY, Kim HS. Reduced radiation exposure of the female breast during low-dose chest CT using organ-based tube current modulation and a bismuth shield: comparison of image quality and radiation dose. AJR Am J Roentgenol. 2013;200:537-44. doi.org/10.2214/AJR.12.9237. PubMed PMID: 23436842.
  6. Zhu X, Yu J, Huang Z. Low-dose chest CT: optimizing radiation protection for patients. AJR Am J Roentgenol. 2004;183:809-16. doi.org/10.2214/ajr.183.3.1830809. PubMed PMID: 15333374.
  7. Tappouni R, Mathers B. Scan Quality and Entrance Skin Dose in Thoracic CT: A Comparison between Bismuth Breast Shield and Posteriorly Centered Partial CT Scans. ISRN Radiol. 2013;2013:457396. doi.org/10.5402/2013/457396. PubMed PMID: 24967274. PubMed PMCID: 4045517.
  8. Angel E, Yaghmai N, Jude CM, DeMarco JJ, Cagnon CH, Goldin JG, et al. Dose to radiosensitive organs during routine chest CT: effects of tube current modulation. AJR Am J Roentgenol. 2009;193:1340-5. doi.org/10.2214/AJR.09.2886. PubMed PMID: 19843751. PubMed PMCID: 2954276.
  9. Linet MS, Slovis TL, Miller DL, Kleinerman R, Lee C, Rajaraman P, et al. Cancer risks associated with external radiation from diagnostic imaging procedures. CA Cancer J Clin. 2012;62:75-100. doi.org/10.3322/caac.21132. PubMed PMID: 22307864. PubMed PMCID: 3548988.
  10. Goldman LW. Principles of CT: radiation dose and image quality. J Nucl Med Technol. 2007;35:213-25; quiz 26-8. doi.org/10.2967/jnmt.106.037846. PubMed PMID: 18006597.
  11. Bauhs JA, Vrieze TJ, Primak AN, Bruesewitz MR, McCollough CH. CT dosimetry: comparison of measurement techniques and devices. Radiographics. 2008;28:245-53. doi.org/10.1148/rg.281075024. PubMed PMID: 18203941.
  12. Shrimpton P, Wall B. Assessment of patient dose from computed tomography. Radiation Protection Dosimetry. 1992;43:205-8.
  13. Bongartz G, Golding S, Jurik A, Leonardi M, Van Meerten E, Geleijns J, et al. European guidelines on quality criteria for computed tomography. EUR(Luxembourg). 1999.
  14. Kubo T, Lin PJ, Stiller W, Takahashi M, Kauczor HU, Ohno Y, et al. Radiation dose reduction in chest CT: a review. AJR Am J Roentgenol. 2008;190:335-43. doi.org/10.2214/AJR.07.2556. PubMed PMID: 18212218.
  15. Kim MJ, Park CH, Choi SJ, Hwang KH, Kim HS. Multidetector computed tomography chest examinations with low-kilovoltage protocols in adults: effect on image quality and radiation dose. J Comput Assist Tomogr. 2009;33:416-21. doi.org/10.1097/RCT.0b013e318181fab5. PubMed PMID: 19478637.
  16. McCollough CH, Bruesewitz MR, McNitt-Gray MF, Bush K, Ruckdeschel T, Payne JT, et al. The phantom portion of the American College of Radiology (ACR) computed tomography (CT) accreditation program: practical tips, artifact examples, and pitfalls to avoid. Med Phys. 2004;31:2423-42. doi.org/10.1118/1.1769632. PubMed PMID: 15487722.
  17. Hurwitz LM, Reiman RE, Yoshizumi TT, Goodman PC, Toncheva G, Nguyen G, et al. Radiation dose from contemporary cardiothoracic multidetector CT protocols with an anthropomorphic female phantom: implications for cancer induction. Radiology. 2007;245:742-50. doi.org/10.1148/radiol.2453062046. PubMed PMID: 17923509.
  18. Sargazi V, Mehnati P. Strategies for breast dose reduction in chest CT scan. International Journal of Analytical, Pharmaceutical, & Biomedical Sciences. 2014;3:66-72.
  19. Hidajat N, Wolf M, Nunnemann A, Liersch P, Gebauer B, Teichgraber U, et al. Survey of conventional and spiral ct doses. Radiology. 2001;218:395-401. doi.org/10.1148/radiology.218.2.r01ja12395. PubMed PMID: 11161152.
  20. Slovis TL. CT and computed radiography: the pictures are great, but is the radiation dose greater than required? AJR Am J Roentgenol. 2002;179:39-41. doi.org/10.2214/ajr.179.1.1790039. PubMed PMID: 12076901.
  21. Abadi S, Mehrez H, Ursani A, Parker M, Paul N. Direct quantification of breast dose during coronary CT angiography and evaluation of dose reduction strategies. AJR Am J Roentgenol. 2011;196:W152-8. doi.org/10.2214/AJR.10.4626. PubMed PMID: 21257856.
  22. McCollough CH, Wang J, Berland LL. Bismuth shields for CT dose reduction: do they help or hurt? J Am Coll Radiol. 2011;8:878-9. doi.org/10.1016/j.jacr.2011.09.001. PubMed PMID: 22137008.
  23. Hohl C, Wildberger JE, Suss C, Thomas C, Muhlenbruch G, Schmidt T, et al. Radiation dose reduction to breast and thyroid during MDCT: effectiveness of an in-plane bismuth shield. Acta Radiol. 2006;47:562-7. doi.org/10.1080/02841850600702150. PubMed PMID: 16875333.