Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain

Background: Epidemiological studies show that computed tomography (CT) is one of the main sources of ionizing radiations. Shielding of radiosensitive organs is one of the dose reduction methods. This study aimed to assess the eye lens dose reduction and image quality resulting from the use of radio-...

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Main Authors: Amin Banaei, Alireza Dadashi, Seyed Salman Zakariaee, Valiallah Saba
Format: Article
Language:English
Published: Kerman University of Medical Sciences 2018-11-01
Series:Journal of Kerman University of Medical Sciences
Subjects:
Online Access:https://jkmu.kmu.ac.ir/article_85236_0601df336f03e3b82449416944dddb00.pdf
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author Amin Banaei
Alireza Dadashi
Seyed Salman Zakariaee
Valiallah Saba
author_facet Amin Banaei
Alireza Dadashi
Seyed Salman Zakariaee
Valiallah Saba
author_sort Amin Banaei
collection DOAJ
description Background: Epidemiological studies show that computed tomography (CT) is one of the main sources of ionizing radiations. Shielding of radiosensitive organs is one of the dose reduction methods. This study aimed to assess the eye lens dose reduction and image quality resulting from the use of radio-protective bismuth shield in brain CT imaging. Methods: Bismuth shields were constructed with two different thicknesses (0.02 and 0.06 cm) and two different geometries including: direct contact with eye (contact setup) and 4 cm above the eye (distant setup). The lens dose was determined using thermo luminescent dosimeter (TLD)-207A chips inside an anthropomorphic head phantom during the CT examinations. Noise, SNR (signal to noise ratio), and CNR (contrast to noise ratio) were calculated to evaluate the image quality. Results: The lens dose reduction was higher using the shield with 0.06 cm thickness and in ‘contact setup’. On the other hand, the bismuth shield with the thickness of 0.02 cm and in ‘distant setup’ had lower dose reduction and better image quality. Conclusion: Bismuth shield with the thickness of 0.02 cm and in ‘distant setup’ could decrease the lens dose to the acceptable levels, while providing a better image quality in comparison with the contact shield setup and with 0.06 cm thickness. Using the bismuth shield is a simple and low cost method for protecting the eye lens in brain CT scans with conventional scanners especially in low income or developing countries.
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spelling doaj.art-97a1b0a7bbba45e68435fa1ac7f909fa2023-07-01T05:17:48ZengKerman University of Medical SciencesJournal of Kerman University of Medical Sciences2008-28432018-11-0125647148285236Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brainAmin Banaei0Alireza Dadashi1Seyed Salman Zakariaee2Valiallah Saba3Department of Radiology, Faculty of Paramedical Sciences, Aja University of Medical Sciences, Tehran, IranAssistant Professor, Department of Infectious Disease, School of Medicine, Aja University of Medical Sciences, Tehran, IranDepartment of Radiology, Faculty of Paramedical Sciences, Aja University of Medical Sciences, Tehran, IranAssociate Professor, Department of Radiology, Faculty of Paramedical Sciences, Aja University of Medical Sciences, Tehran, IranBackground: Epidemiological studies show that computed tomography (CT) is one of the main sources of ionizing radiations. Shielding of radiosensitive organs is one of the dose reduction methods. This study aimed to assess the eye lens dose reduction and image quality resulting from the use of radio-protective bismuth shield in brain CT imaging. Methods: Bismuth shields were constructed with two different thicknesses (0.02 and 0.06 cm) and two different geometries including: direct contact with eye (contact setup) and 4 cm above the eye (distant setup). The lens dose was determined using thermo luminescent dosimeter (TLD)-207A chips inside an anthropomorphic head phantom during the CT examinations. Noise, SNR (signal to noise ratio), and CNR (contrast to noise ratio) were calculated to evaluate the image quality. Results: The lens dose reduction was higher using the shield with 0.06 cm thickness and in ‘contact setup’. On the other hand, the bismuth shield with the thickness of 0.02 cm and in ‘distant setup’ had lower dose reduction and better image quality. Conclusion: Bismuth shield with the thickness of 0.02 cm and in ‘distant setup’ could decrease the lens dose to the acceptable levels, while providing a better image quality in comparison with the contact shield setup and with 0.06 cm thickness. Using the bismuth shield is a simple and low cost method for protecting the eye lens in brain CT scans with conventional scanners especially in low income or developing countries.https://jkmu.kmu.ac.ir/article_85236_0601df336f03e3b82449416944dddb00.pdfcomputed tomographylens dose reductionbismuth shieldingimage quality
spellingShingle Amin Banaei
Alireza Dadashi
Seyed Salman Zakariaee
Valiallah Saba
Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
Journal of Kerman University of Medical Sciences
computed tomography
lens dose reduction
bismuth shielding
image quality
title Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
title_full Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
title_fullStr Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
title_full_unstemmed Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
title_short Assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
title_sort assessing the image quality and eye lens dose reduction using bismuth shielding in computed tomography of brain
topic computed tomography
lens dose reduction
bismuth shielding
image quality
url https://jkmu.kmu.ac.ir/article_85236_0601df336f03e3b82449416944dddb00.pdf
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