Thomas Diebold MD, Presenter: Nothing to Disclose

Thomas Mertelmeier, Abstract Co-Author: Nothing to Disclose

David Nadas, Abstract Co-Author: Nothing to Disclose

Christine Solbach MD, Abstract Co-Author: Nothing to Disclose

Volkmar Jacobi MD, Abstract Co-Author: Nothing to Disclose

Manfred Kaufmann, Abstract Co-Author: Nothing to Disclose

Thomas Josef Vogl MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Determination of average glandular dose (AGD) in selenium-based full-field digital mammography (a-Se FFDM) in comparison to conventional screen-film mammography (SFM).

Out of more than 250 examinations 78 a-Se FFDM mammograms (Siemens Mammomat Novation DR) of patients who formerly (max. 2 years) underwent conventional screen film mammography (Siemens Mammomat Nova 3000) were selected to compare glandular dose with both methods. Inclusion criteria were unchanged parameters for breast thickness, breast glandularity and compression force in SFM and FFDM. All cases with interval surgery and not previously visible mammographic lesions were excluded. FFDM and SFM were acquired using automatic exposure control. Patient data (anode/filter combination, kV, mAs, compression thickness and glandularity) were recorded for SFM and FFDM. The entrance surface air kerma (ESAK) was calculated and AGD was determined by multiplying ESAK by the conversion factors g, c and s as tabulated by Dance.

The a-Se FFDM selected tungsten/rhodium as anode/filter combination for all patients whereas SFM selected molybdenum/molybdenum in 56 and tungsten/rhodium in 22 cases. The use of a-Se FFDM resulted in significantly lower radiation doses compared to SFM. In FFDM the mean AGD was 0.83 mGy (0.53-1.25mGy) compared to 1.41 mGy (0.71-2.53mGy) in SFM. In the selen based FFDM the mean dose reduction per image was 41% compared to SFM. The maximum dose reduction with FFDM was 61%, in 1 case the dose in FFDM was 12% higher than SFM.

The use of selen based FFDM in our study resulted in a significant reduction of AGD and the percentage of dose reduction is comparable to the published data with respect to cesium iodide-based detectors.

The comparable/better diagnostic performance of FFDM vs SFM and the reduced glandular dose of cesium iodide-based detectors are well known. Our study revealed similar dose reduction for the a-Se FFDM.

Diebold, T, Mertelmeier, T, Nadas, D, Solbach, C, Jacobi, V, Kaufmann, M, Vogl, T, et al, , et al, , Evaluation of Glandular Dose in Selenium-based Full-Field Digital Mammography in Comparison to Screen-film Mammography.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5016668.html