Low and Achievable: Breast Dose Reduction in Thorax CT

Congress:

EuroSafe Imaging 2017

Poster Number:

ESI-0046

Type:

EuroSafe Imaging

Keywords:

CT, Breast, Action 8 - Radiation protection training and learning material, Action 2 - Clinical diagnostic reference levels (DRLs), Action 6 - Education and training in medical radiation protection, Action 3 - Optimisation, diagnostic reference levels, image quality, Radiation safety, Dosimetric comparison

Authors:

D. Akata, M. R. Onur, M. G. Akpinar, G. Durhan, M. Ariyürek, O. Öcal, M. N. Özmen

DOI:

10.1594/esi2017/ESI-0046

DOI-Link:

https://dx.doi.org/10.1594/esi2017/ESI-0046

Fig. 2: OBTCM. Illustration of a CT gantry and tube reveals decrease in tube current...

Fig. 3: Axial chest CT image of a 66 year-old female. CT examination was performed with...

Background/Introduction

Radiation dose in breast tissue concerns physicians because of its relative high sensitivity to radiation compared with other organs in the thorax. Absorbed breastdoses are reported in the range of 4.3–66 mGy with current MDCT techniques that makes young women to be of particular concern (Table 1). Breast tissue-weighting factor was increased to 0.12 from 0.05. Table 1 CT Examination Mean Breast Dose Pulmonary CT Angiography 20-60 mGy Chest CT 20-50 mGy Abdomen CT 10-20 mGy

Description of activity and work performed

In this presentation, we summarized the breast dose reduction methods in chest CT. Breast Dose Reduction Methods 1. Bismuth shielding 2. Organ-based tube current modulation 3. Iterative reconstruction 4.Total dose reduction 1. Bismuth Shielding Bismuth shields (Figs. 1) Decrease dose:Reduces %30 breast dose in the absence of organ based tube current modulation Increase noise Increase artifacts (beam-hardening, streak) Breast shields should not be applied before the scout planning image is acquired because pre-scout image bismuth shielding results in higher patient attenuation leading to increased tube...

Conclusion and Recommendations

The number of chest CT examinations has been increasing with the risk of increased exposure of breast Importance of protecting breast tissue in chest CT should be well-known. Breast dose in chest CT can be reduced by using OBCTM, bismuth shielding and total dose reduction techniques.

Personal/Organisational information

1. Mehmet Ruhi Onur, M.D. 2. Meltem Gülsün Akpinar, M.D. 3. Gamze Durhan, M.D. 4. Macit Ariyurek, M.D. 5. Osman Ocal, M.D. 6. Mustafa Ozmen, M.D. 7. Deniz Akata, M.D. Hacettepe University Faculty of Medicine, Department of Radiology, Ankara, Turkey

References

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