Comparative Study of the Use of Bismuth Shielding on Head Computed Tomography Scans Using Phantoms
DOI:
https://doi.org/10.15392/bjrs.v8i1B.936Keywords:
Computed Tomography, Bismuth Shielding, DosimetryAbstract
Computed Tomography (CT) has been one of the most used exam for radiologic diagnostic in medicine. The increase of CT is a global concern due to high doses of radiation. The dose evaluation in CT is one of many steps that can contribute for reducing patient doses. The head CT scans helps to diagnose disorders that affect the brain, including tumors, infarction, bleeding within the brain, hematoma and other diseases. The aim of this work is to compare the reduction of absorbed dose in the head CT scan with and without the use of bismuth shielding using a male and female anthropomorphic phantom model Alderson Rando.The head CT scan were done from the cervical vertebra C1 to the top of skull, in a GE CT scanner, LightSpeed VCT model, with 64 channels.Radiochromic films strips were used to evaluate the doses in the organs such as lenses, thyroid, hypophysis, spinal cord, pharynx, breasts, salivary and parotid glands.Record doses were lower with the use of bismuth shielding in both phantoms for all organs, mainly in the lenses. The analysis of noise in the image of the head central slice presented acceptable values for soft tissues, less than 1%. Dose values were significantly reduced and they suggested that the use of bismuth shielding would be a proper procedure for protection during a head CT scan.Downloads
References
ALONSO, T.C; MOURÃO, A.P; SANTANA, P.C; SILVA, T.A. Assessment of breast absorbed doses during thoracic computed tomography scan to evaluate the effectiveness of bismuth shielding. Applied Radiation and Isotopes, v. 117, p. 55-57, 2016.
INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION ICRP, Statement on tis-sue reactions/early and late effects of radiation in normal tissues and organs-threshold doses for tissue reactions in a radiation protection context, Publication 118 (2012).
P. Colleti et al., “To shield or not to shield: application of bismuth breast shields”, AJR, Vol. 200, pp. 503-507 (2013).
GIADDUI, T; CUI, Y. J; GALVIN, W; CHEN, Y; YU, Y; XIAO, Y. Characteristics of Gafchromic XRQA2 films for kV image dose measurement. Medical Physics, v. 39, p. 842-850, 2012.
MOURÃO, A. P; ALONSO, T. C; SILVA, T. A. Dose profile variation with voltage in head CT scans using radiochromic films. Radiation Physics and Chemistry, v. 95, p. 254-257, 2014.
COSTA, K. C; GOMEZ, A. M. L; ALONSO, T. C; MOURÃO, A. P. Radiochromic film calibration for the RQT9 quality beam. Radiantion Physics and Chemistry, v. 140, p. 370-372, 2017.
Published
Issue
Section
Categories
License
Copyright (c) 2020 Brazilian Journal of Radiation Sciences
This work is licensed under a Creative Commons Attribution 4.0 International License.
Licensing: The BJRS articles are licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
How to Cite
