Skip to main content

Entrance surface dose measurements using a small OSL dosimeter with a computed tomography scanner having 320 rows of detectors

Radiological Physics and Technology volume 10, pages 49–59 (2017)Cite this article

Abstract

Entrance surface dose (ESD) measurements are important in X-ray computed tomography (CT) for examination, but in clinical settings it is difficult to measure ESDs because of a lack of suitable dosimeters. We focus on the capability of a small optically stimulated luminescence (OSL) dosimeter. The aim of this study is to propose a practical method for using an OSL dosimeter to measure the ESD when performing a CT examination. The small OSL dosimeter has an outer width of 10 mm; it is assumed that a partial dose may be measured because the slice thickness and helical pitch can be set to various values. To verify our method, we used a CT scanner having 320 rows of detectors and checked the consistencies of the ESDs measured using OSL dosimeters by comparing them with those measured using Gafchromic™ films. The films were calibrated using an ionization chamber on the basis of half-value layer estimation. On the other hand, the OSL dosimeter was appropriately calibrated using a practical calibration curve previously proposed by our group. The ESDs measured using the OSL dosimeters were in good agreement with the reference ESDs from the Gafchromic™ films. Using these data, we also estimated the uncertainty of ESDs measured with small OSL dosimeters. We concluded that a small OSL dosimeter can be considered suitable for measuring the ESD with an uncertainty of 30 % during CT examinations in which pitch factors below 1.000 are applied.

This is a preview of subscription content, access via your institution.

Access options

Buy single article

Instant access to the full article PDF.

43,34 €

Price includes VAT (Finland)
Tax calculation will be finalised during checkout.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

References

  1. Gonalez AB, Darby S. Risk of cancer from diagnostic X-ray: estimates for the UK and 14 other countries. Lancet. 2004;363:345–51. doi:10.1016/S0140-6736(04)15433-0.

    Article  Google Scholar 

  2. Uffmann M, Schaefer-Prokop C. Digital radiography: the balance between image quality and required radiation dose. Eur J Radiol. 2009;72:202–8. doi:10.1016/j.ejrad.2009.05.060.

    Article  PubMed  Google Scholar 

  3. Gardner SJ, Studenski MT, Giaddui T, et al. Investigation into image quality and dose for different patient geometries with multiple cone-beam CT systems. Med Phys. 2014;41(3):031908. doi:10.1118/1.4865788.

    Article  PubMed  PubMed Central  Google Scholar 

  4. Goldman LW. Principles of CT: radiation dose and image quality. J Nucl Med Thecnol. 2007;35(4):213–25. doi:10.2967/jnmt.106.037846.

    Article  Google Scholar 

  5. Mathews JD, Forsythe AV, Brady Z, et al. Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ. 2013;346:f2360. doi:10.1136/bmj.f2360.

    Article  PubMed  PubMed Central  Google Scholar 

  6. McCollough CH, Leng S, Yu L, et al. CT dose index and patient dose: they are not the same thing. Radiol. 2011;259:311–6. doi:10.1148/radiol.11101800.

    Article  Google Scholar 

  7. Koyama S, Aoyama T, Oda N, et al. Radiation dose evaluation in tomosynthesis and C-arm cone-beam CT examinations with an anthropomorphic phantom. Med Phys. 2010;. doi:10.1118/1.3465045.

    Google Scholar 

  8. McDermott A, White RA, Mc-Nitt-Gray M, et al. Pediatric organ dose measurements in axial and helical multislice CT. Med Phys. 2009;36(5):1494–9. doi:10.1118/1.3101817.

    Article  PubMed  PubMed Central  Google Scholar 

  9. Tsalatoutas IA, Epistatou A, Nikoletopoulos S, et al. Measuring skin dose in CT examinations under complex geometries: instruments, methods and considerations. Physica Med. 2015;31:1005–14. doi:10.1016/j.ejmp.2015.08.001.

    Article  Google Scholar 

  10. 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;. doi:10.5402/2013/457396 (article ID 457396).

    PubMed  Google Scholar 

  11. Duan X, Wang J, Christner JA, et al. Dose reduction to anterior surfaces with organ-based tube-current modulation: evaluation of performance in a phantom study. Am J Roentgenol. 2011;197:689–95. doi:10.2214/AJR.10.6061.

    Article  Google Scholar 

  12. Tominaga M, Kawata Y, Niki N, et al. Measurements of multidetector CT surface dose distributions using a film dosimeter and chest phantom. Med Phys. 2011;38:2467. doi:10.1118/1.3570769.

    Article  PubMed  Google Scholar 

  13. Westra SJ, Li X, Gulati K, et al. Entrance skin dosimetry and size-specific dose estimate from pediatric chest CTA. J Cardiovasc Comput Tomogr. 2014;8:97–107. doi:10.1016/j.jcct.2013.08.002.

    Article  PubMed  Google Scholar 

  14. Ramac JP, Knezevic Z, Hebrang A, et al. Radiation dose reduction by using low dose CT protocol of thorax. Radiat Meas. 2013;55:46–50. doi:10.1016/j.radmeas.2012.07.012.

    Article  Google Scholar 

  15. Cordasco C, Portelli M, Militi A, et al. Low-dose protocol of the spiral CT in orthodontics: comparative evaluation of entrance skin dose with traditional X-ray techniques. Prog Orthod. 2013;14:24. doi:10.1186/2196-1042-14-24.

    Article  PubMed  PubMed Central  Google Scholar 

  16. Takegami K, Hayashi H, Okino H, et al. Estimation of identification limit for a small-type OSL dosimeter on the medical images by measurement of X-ray spectra. Radiol Phys Technol. 2016;. doi:10.1007/s12194-016-0362-5 (in press).

    Google Scholar 

  17. Takegami K, Hayashi H, Nakagawa K, et al. Measurement method of an exposed dose using the nanoDot dosimeter. Eur Con Radiol (EPOS). 2015;. doi:10.1594/ecr2015/C-0218.

    Google Scholar 

  18. Hayashi H, Nakagawa K, Okino H, et al. High accuracy measurements by consecutive readings of OSL dosimeter. Med Imaging Inf Sci. 2014;31(2):28–34. doi:10.11318/mii.31.28.

    Google Scholar 

  19. Nakagawa K, Hayashi H, Takegami K, et al. Fabrication of annealing equipment for optically stimulated luminescence (OSL) dosimeter. Jpn J Radiol Technol. 2014;70(10):1135–42. doi:10.6009/jjrt.2014_JSRT_70.10.1135.

    Article  Google Scholar 

  20. Hayashi H, Takegami K, Okino H, et al. Procedure to measure angular dependences of personal dosimeters by means of diagnostic X-ray equipment. Med Imaging Inf Sci. 2015;32(1):8–14. doi:10.11318/mii.32.8.

    Google Scholar 

  21. Takegami K, Hayashi H, Okino H, et al. Energy dependence measurement of small-type optically stimulated luminescence (OSL) dosimeter by means of characteristic X-rays induced with general diagnostic X-ray equipment. Radiol Phys Technol. 2016;9:99–108. doi:10.1007/s12194-015-0339-9.

    Article  PubMed  Google Scholar 

  22. Takegami K, Hayashi H, Okino H, et al. Practical calibration curve of small-type optically stimulated luminescence (OSL) dosimeter for evaluation of entrance-skin dose in the diagnostic X-ray. Radiol Phys Technol. 2015;8:286–94. doi:10.1007/s12194-015-0318-1.

    Article  PubMed  Google Scholar 

  23. Giaddui T, Cui Y, Galvin J, et al. Comparative dose evaluations between XVI and OBI cone beam CT systems using Gafchromic™ XRQA2 films and nanoDot optical stimulated luminescence dosimeters. Med Phys. 2013;40:062102. doi:10.1118/1.4803466.

    Article  PubMed  Google Scholar 

  24. Tomic N, Devic S, DeBlois F, et al. Reference radiochromic film dosimetry in kilovoltage photon beams during CBCT image acquisition. Med Phys. 1083;2010:37. doi:10.1118/1.3302140.

    Google Scholar 

  25. Yamashiro T, Miyara T, Honda O, et al. Adaptive iterative dose reduction Using three dimensional processing (AIDR 3D) improves chest CT image quality and reduces radiation exposure. PLoS One. 2014;9(8):e105735. doi:10.1371/journal.pone.0105735.

    Article  PubMed  PubMed Central  Google Scholar 

  26. Yamada Y, Jinzaki M, Hosokawa T, et al. Dose reduction in chest CT: comparison of the adaptive iterative dose reduction 3D, adaptive iterative dose reduction, and filtered back projection reconstruction techniques. Eur J Radiol. 2012;81:4185–95. doi:10.1016/j.ejrad.2012.07.013.

    Article  PubMed  Google Scholar 

  27. D’Alessio D, Giliberti C, Soriani A, et al. Dose evaluation for skin and organ in hepatocellular carcinoma during angiographic procedure. J Exp Clin Cancer Res. 2013;32:81. doi:10.1186/1756-9966-32-81.

    Article  PubMed  PubMed Central  Google Scholar 

  28. Sabarudin A, Sun Z. Radiation dose measurement in coronary CT angiography. World J Cardiol. 2013;5(12):459–64. doi:10.4330/wjc.v5.i12.459.

    PubMed  PubMed Central  Google Scholar 

  29. Christner JA, Kofler JM, McCollough CH. Estimating effective dose for CT using dose-length product compared with using organ doses: consequences of adopting international commission on radiological protection publication 103 or dual-energy scanning. Am J Rentgenol. 2010;194:881–9. doi:10.2214/AJR.09.3462.

    Article  Google Scholar 

  30. Hubbell JH. Photon mass attenuation and energy-absorption coefficients. Int J Appl Radiat Isotopes. 1982;33(11):1269–90. doi:10.1016/0020-708X(82)90248-4.

    CAS  Article  Google Scholar 

Download references

Acknowledgments

This work was supported by JSPS KAKENHI Grant Number 15K19205.

Author information

Author notes

  1. Kazuki Takegami

    Present address: Yamaguchi University Hospital, 1-1-1, Minamikogushi, Ube, Yamaguchi, 755-8505, Japan

Affiliations

  1. Graduate School of Health Sciences, Tokushima University, 3-18-5 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan

    Kazuki Takegami & Natsumi Kimoto

  2. Graduate School of Biomedical Sciences, Tokushima University, 3-18-5 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan

    Hiroaki Hayashi, Yuki Kanazawa, Kousaku Higashino, Kazuta Yamashita & Fumio Hayashi

  3. Tokushima University Hospital, 3-18-5 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan

    Kenji Yamada, Kousaku Higashino, Kazuta Yamashita & Fumio Hayashi

  4. School of Health Sciences, Tokushima University, 3-18-5 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan

    Yoshiki Mihara

  5. Nagase-Landauer, Ltd., C22-1 Suwa, Tsukuba, Ibaraki, 300-2686, Japan

    Tohru Okazaki, Takuya Hashizume & Ikuo Kobayashi

Authors
  1. Kazuki Takegami
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Hiroaki Hayashi
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Kenji Yamada
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Yoshiki Mihara
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Natsumi Kimoto
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Yuki Kanazawa
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Kousaku Higashino
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Kazuta Yamashita
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Fumio Hayashi
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Tohru Okazaki
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Takuya Hashizume
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. Ikuo Kobayashi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Hiroaki Hayashi.

Ethics declarations

Conflict of interest

T Okazaki, T. Hashizume, and I. Kobayashi are employees of Nagase Landauer Ltd. and collaborating researchers.

About this article

Verify currency and authenticity via CrossMark

Cite this article

Takegami, K., Hayashi, H., Yamada, K. et al. Entrance surface dose measurements using a small OSL dosimeter with a computed tomography scanner having 320 rows of detectors. Radiol Phys Technol 10, 49–59 (2017). https://doi.org/10.1007/s12194-016-0366-1

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12194-016-0366-1

Keywords

  • OSL dosimeter
  • Gafchromic™ film
  • Entrance surface dose
  • Computed tomography