DOSIMETRY IN DIGITAL BREAST TOMOSYNTHESIS: COST-EFFICIENT APPROACH FOR THE SOUTH AMERICAN PERSPECTIVES.

Area of Science:

• Medical Physics
• Radiological Imaging
• Radiation Dosimetry

Background:

• Estimating average glandular dose (AGD) in digital breast tomosynthesis (DBT) is challenging due to the rotating X-ray tube.
• Accurate dose measurement is crucial for patient safety and optimizing imaging protocols.

Purpose of the Study:

• To develop and validate a novel, cost-effective methodology for measuring air kerma (Kair) during DBT acquisitions with a rotating X-ray tube.
• To apply this method for estimating AGD in both phantom and patient studies.

Main Methods:

• A low economic cost support (LCS) was designed to hold aluminium sheets and a calibrated dosemeter during X-ray tube rotation.
• Measurements were performed on three Fujifilm Innovality DBT systems using dosemeters calibrated on W-Al energies.
• The methodology was validated against standard dosimetry protocols.

Main Results:

• The novel LCS methodology demonstrated satisfactory validation against standard methods.
• The difference in AGD calculated using the LCS and DICOM Header was less than ±10%.
• Estimated AGD values ranged from 0.77 to 2.11 mGy for phantoms and 0.85 to 2.15 mGy for patients.

Conclusions:

• The developed LCS methodology provides a reliable and cost-effective way to measure Kair and estimate AGD during DBT.
• This technique is particularly valuable for DBT equipment lacking a stationary mode.
• The findings support improved radiation dose assessment in tomosynthesis imaging.