Estratégias de Otimização da Dose de Radiação em Angiotomografia Abdominal

Authors

  • MURILO Assunção Universidade Federal de São Paulo
  • Thiago Souza Dias Universidade Federal de São Paulo
  • Rodrigo Azambuja Hospital do Rim
  • Regina Bitelli Medeiros Bitelli
  • Marcelo Freitas Universidade Federal de São Paulo

DOI:

https://doi.org/10.29384/rbfm.2021.v15.19849001631

Keywords:

medical physics, radiology, Computed tomography, optimization, iterative reconstruction, angiotomography

Abstract

This paper shows strategies for dose management and image quality in multiphase abdominal computed tomography angiography using technologies available in a 64-channel CT scanner. The implementation of current modulation techniques, iterative reconstruction algorithms and voltage variation to improve the contrast of images are described using phantom tests. The computed tomography dose index (CTDI) in the full exam was reduced by 12.4%, and in the arterial phase the reduction was 32%. Associated with this, the contrast-to-noise ratio (CNR) measured in the contrasted image (iodine) of the artery in the abdominal region increased by 35.8%, reinforcing the effectiveness of optimization strategies. The use of lower values of voltage in the arterial phase in association with the increase in the levels of iterative reconstruction and reduction in the levels of current modulation resulted in a lower dose of radiation in angiotomography, still guaranteeing clinical images with diagnostic quality.

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References

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Published

2021-09-29

How to Cite

Assunção, M. ., Souza Dias, T., Azambuja, R. ., Bitelli , R. B. M., & Freitas, M. . (2021). Estratégias de Otimização da Dose de Radiação em Angiotomografia Abdominal. Brazilian Journal of Medical Physics, 15, 631. https://doi.org/10.29384/rbfm.2021.v15.19849001631

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Section

Artigo Original

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