The Current Use and Effectiveness of Bismuth Shielding in Computed Tomography: A Systematic Review

Abstract

Background: The increased use of computed tomography (CT) has raised concerns regarding
the radiation dose received by radiosensitive organs. It is important that practical and reliable
dose reduction strategies are implemented to reduce patient radiation exposure.
Aims: The purpose of this article is to evaluate the current clinical use and effectiveness of
bismuth shielding as a dose reduction technique and assess its impact on image quality, in an
attempt to develop a recommendation for dose reduction in CT.
Methods: A systematic review of current literature was conducted using the PubMed and Scopus
databases. A total of 50 relevant articles were thoroughly assessed and evaluated.
Results: This review found that whilst bismuth shielding proves to provide significant dose reductions
to radiosensitive organs, numerous concerns exist including wasted radiation, reduced
image quality and unpredictable results when combined with AEC. Alternative methods such
as tube current modulation and iterative reconstruction algorithms can provide equivalent dose
savings at superior image quality, without the limitations of bismuth shields.
Conclusion: Until these alternative methods become available in all departments, bismuth
shielding remains a viable dose reduction strategy.