Average glandular dose with amorphous silicon full-field digital mammography - Clinical results.

PURPOSE

Determination of average glandular dose with a full-field digital mammography system using a flat-panel X-ray detector based on amorphous silicon technology for a large group of patients.

MATERIAL AND METHODS

The patient group includes women who were examined in a 4-month period with the digital mammographic system Senographe 2000D. The number of women was 591 and the number of exposures was 1116; only cranio-caudal projections were considered. Various quantities, including entrance surface air kerma, tube loading, and compressed breast thickness, were determined during actual mammography. Average glandular dose was determined using conversion factors g for standard breast composition.

RESULTS

The mean average glandular dose was 1.51 mGy (0.66 - 4.05 mGy) for a single view. The mean compressed breast thickness was 55.7 mm. The mean age of patients was 55 years (34 - 81 years).

CONCLUSION

The results demonstrate that full-field digital mammography with a flat-panel detector based on amorphous silicon needs about 25 % less dose in comparison with conventional screen-film mammography.