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Determination of Scattered Radiation to the Thyroid Gland in Dental Cone Beam Computed Tomography

  • Wilson Hrangkhawl (Department of Medical Imaging Technology, Manipal College of Health Professions, Manipal Academy of Higher Education) ;
  • Winniecia Dkhar (Department of Medical Imaging Technology, Manipal College of Health Professions, Manipal Academy of Higher Education) ;
  • T.S. Madhavan (Department of Medical Imaging Technology, School of Allied Sciences, Jaipur National University) ;
  • S. Sharath (Department of Medical Imaging Technology, Manipal College of Health Professions, Manipal Academy of Higher Education) ;
  • R. Vineetha (Department of Oral and Dental Radiology, Manipal College of Dental Sciences, Manipal Academy of Higher Education) ;
  • Yogesh Chhaparwal (Department of Oral and Dental Radiology, Manipal College of Dental Sciences, Manipal Academy of Higher Education)
  • 투고 : 2021.10.30
  • 심사 : 2022.08.23
  • 발행 : 2023.03.31

초록

Background: Cone beam computed tomography (CBCT) is a specialized medical equipment and plays a significant role in the diagnosis of oral and maxillofacial diseases and abnormalities; however, it is attributed to risk of exposure of ionizing radiation. The aim of the study was to estimate and determine the amount of scattered radiation dose to the thyroid gland in dental CBCT during maxilla and mandible scan. Materials and Methods: The average scattered radiation dose for i-CAT 17-19 Platinum CBCT (Imaging Sciences International) was measured using a Multi-O-Meter (Unfors Instruments), placed at the patient's neck on the skin surface of the thyroid cartilage, with an exposure parameter of 120 kVp and 37.07 mAs. The surface entrance dose was noted using the Multi-O-Meter, which was placed at the time of the scan at the level of the thyroid gland on the anterior surface of the neck. Results and Discussion: The surface entrance dose to the thyroid from both jaws scans was 191.491±78.486 µGy for 0.25 mm voxel and 26.9 seconds, and 153.670±74.041 µGy from the mandible scan, whereas from the maxilla scan the surface entrance dose was 5.259±10.691 µGy. Conclusion: The surface entrance doses to the thyroid gland from imaging of both the jaws, and also from imaging of the maxilla and mandible alone were within the threshold limit. The surface entrance dose and effective dose in CBCT were dependent on the exposure parameters (kVp and mAs), scan length, and field of view. To further reduce the radiation dose, care should be taken in selecting an appropriate protocol as well as the provision of providing shielding to the thyroid gland.

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참고문헌

  1. Scarfe WC, Farman AG. What is cone-beam CT and how does it work? Dent Clin North Am. 2008;52(4):707-730. https://doi.org/10.1016/j.cden.2008.05.005
  2. Abramovitch K, Rice DD. Basic principles of cone beam computed tomography. Dent Clin North Am. 2014;58(3):463-484. https://doi.org/10.1016/j.cden.2014.03.002
  3. Silva MA, Wolf U, Heinicke F, Bumann A, Visser H, Hirsch E. Cone-beam computed tomography for routine orthodontic treatment planning: a radiation dose evaluation. Am J Orthod Dentofacial Orthop. 2008;133(5):640.
  4. Cordasco G, Portelli M, Militi A, Nucera R, Lo Giudice A, Gatto E, 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.
  5. Nascimento HA, Andrade ME, Frazao MA, Nascimento EH, Ramos-Perez FM, Freitas DQ. Dosimetry in CBCT with different protocols: emphasis on small FOVs including exams for TMJ. Braz Dent J. 2017;28(4):511-516. https://doi.org/10.1590/0103-6440201701525
  6. The 2007 Recommendations of the International Commission on Radiological Protection. ICRP publication 103. Ann ICRP. 2007;37(2-4):1-332.
  7. Sinnott B, Ron E, Schneider AB. Exposing the thyroid to radiation: a review of its current extent, risks, and implications. Endocr Rev. 2010;31(5):756-773. https://doi.org/10.1210/er.2010-0003
  8. Ling S, Bhatt AD, Brown NV, Nguyen P, Sipos JA, Chakravarti A, et al. Correlative study of dose to thyroid and incidence of subsequent dysfunction after head and neck radiation. Head Neck. 2017;39(3):548-554. https://doi.org/10.1002/hed.24643
  9. Pauwels R, Horner K, Vassileva J, Rehani MM. Thyroid shielding in cone beam computed tomography: recommendations towards appropriate use. Dentomaxillofac Radiol. 2019;48(7):20190014.
  10. Yeh JK, Chen CH. Estimated radiation risk of cancer from dental cone-beam computed tomography imaging in orthodontics patients. BMC Oral Health. 2018;18(1):131.
  11. Visakh T, Sukumar S, Pradhan A. Estimation of entrance surface radiation dose to thyroid region in computed tomography brain examination. Asian J Pharm Clin Res. 2019;12(1):121-123. https://doi.org/10.22159/ajpcr.2019.v12i1.28932
  12. Pauwels R, Cockmartin L, Ivanauskaite D, Urboniene A, Gavala S, Donta C, et al. Estimating cancer risk from dental cone-beam CT exposures based on skin dosimetry. Phys Med Biol. 2014;59(14):3877-3891. https://doi.org/10.1088/0031-9155/59/14/3877
  13. Akyalcin S, English JD, Abramovitch KM, Rong XJ. Measurement of skin dose from cone-beam computed tomography imaging. Head Face Med. 2013;9:28.
  14. Ghanbarnezhad Farshi R, Mesbahi A, Johari M, Kara U, Gharehaghaji N. Dosimetry of critical organs in maxillofacial imaging with cone-beam computed tomography. J Biomed Phys Eng. 2019;9(1):51-60. https://doi.org/10.31661/jbpe.v9i1Feb.691
  15. Heiden KR, Rocha AS, Filipov D, Salazar CB, Fernandes A, Westphalen FH, et al. Absorbed doses in salivary and thyroid glands from panoramic radiography and cone beam computed tomography. Res Biomed Eng. 2018;34(1):31-36. https://doi.org/10.1590/2446-4740.03717