Radioprotection No 59-1 | Page 59

O . Nhila et al .: Radioprotection 2024 , 59 ( 1 ), 50 – 54 53

Table 3 . LDRLs for breast cancer CT-RT protocols in Morocco , compared to other DRLs .

Dosimetric quantities

CTDI vol ( mGy ) DLP ( mGy . cm )

Breast 6.8 10 16 13.3 330.4 390 731 606.6 acquisition parameters , notably kV and mAs settings , which have a significant effect on CTDIvol , as proven in previous studies ( Elojeimy , Tipnis and Huda , 2010 ; El Mansouri et al ., 2021 ; Talbi et al ., 2021 ).

When comparing dose indicators between diagnostic CT scanners , kV setting and AEC mode can be major factors influencing results ( Papadakis and Damilakis , 2018 ; Bebbington et al ., 2021 ). However , in CT-RT protocols , practically all centers use 120 kV setting and avoid AEC technologies adjusting tube voltage to provide unchangeable conversion of attenuation coefficients to electron density , making this parameter insignificant .

4.1 Limitation and perspective

Firstly , the sample size for this study was limited , and patient weight data were not available , thereby making assessment of body size ’ s effect on the NRD value impossible . Secondly , DRL values were established in a single Moroccan center and included data from a single CT examination . Future studies could include other body examinations and variation of scanner brands in several hospitals . Finally , we have established DRLs for CT-RT breast cancer in order to optimize the risk of radiationinduced cancer , especially given the high radiosensitivity of the contralateral breast . Several studies have established DRLs for pediatric CT procedures ( Bawazeer et al ., 2022 ; Geryes et al ., 2022 ; Akhlaghi et al ., 2014 ), but as far as we know , no study has addressed DRLs for pediatric CT-RT protocols , and for this reason we would like to eventually explore this issue .

5 Conclusion

In recent years , researchers have approached the establishment of DRLs for CT-RT to provide a platform for dose comparison and optimization of CT procedures . To our knowledge , only a few European countries have been able to establish DRLs for the most common localizations such as pelvis , ORL , and Breast in their countries . This is the first Moroccan study to establish CT-RT breast cancer DRLs in a single institution . The local NRDs established showed good radiation protection practices in this hospital . Therefore , the results of this study could be a benchmark for the establishment of local and national DRLs in

Morocco and the optimization of CT-RT breast cancer procedures .

Conflict of interest

The authors declare that they have no conflicts of interest in relation to this article .

Funding There was no funding from any source for this study .

Ethical approval

This study did not carry out activities that would require approval by a research ethics committee .

Informed consent

This article does not contain any studies involving human subjects .

Authors contributions

All authors contributed to the design and implementation of the research , to the analysis of the results and to the writing of the manuscript . All authors read and approved the final version of the paper .

References

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Akhlaghi P , Miri Hakimabad H , Rafat Motavalli L . 2014 . An overview of exposure parameters , dose measurements and strategies for dose reduction in pediatric CT examinations . Radioprotection 49 ( 1 ): 9 – 15 . https :// doi . org / 10.1051 / radiopro / 2013072 .

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Bebbington NA , et al . 2021 . Validation of CARE kV automated tube voltage selection for PET-CT : PET quantification and CT radiation