Congress:
EuroSafe Imaging 2017
Keywords:
Dosimetric comparison, Physics, Experimental investigations, Dosimetry, Mammography, Radioprotection / Radiation dose, Radiation physics, 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, Occupational / Environmental hazards, Quality assurance
Authors:
M. Verius, P. Torbica, M. Nagele, M. Daniaux, W. Jaschke
DOI:
10.1594/esi2017/ESI-0010
Description of activity and work performed
In this study an automated data acquisition of regular mammographic examinations (cranio caudal,
CC and medio-lateral oblique,
MLO ) was performed.
This was realized by a self-programmed software „SumDose“ which retrieves the mammographic dicom datasets from our PACS and extracts dicom header parameters for further analysis.
Retrospective data were gained from January 2014 to April 2016,
in total ~55.000 images.
We investigated dicom header parameters gained from a Siemens Mammomat Inspiration (Erlangen,
Germany) mammographic system.
Data analysis focus was on the relation of compressed breast thickness (BodyPartThickness,
BPT) and its dose relevant parameters during the mammographic examination: Tube Voltage [kV],
Exposure [mAs],
OrganDose [dGy],
Entrance Dose [mGy] and Compression Force [N].
Mean Compression force for all examinations was 83.88 N (+/- 37.8 N) and mean breast thickness 50.32 mm (+/- 14.83 mm).
The tube voltage (kilo Volts,
kV) showed a stepped course,
where the change from the lower to the higher voltage can be observed in the breast thickness range from 18 to 20 mm,
28 to 30 mm,
… ,
and 98 to 100 mm (Figure 1 and Figure 2).
In this range the exposure also known as tube current-time-product (milli Ampere seconds,
mAs) changes,
in an inverse way,
i.e.,
it decreases in average with -8.03 mAs (+/-8.84 mAs),
see Figure 3 and Figure 4.
The increase of tube voltage and the decrease of exposure results in an average organ dose decrease of -48.58 µGy (+/-60.5 µGy),
or relatively -3.24% (+/-3.57) see Figure 5 and Figure 6 in detail.