Phantoms for quality control procedures of digital breast tomosynthesis

For quality control (QC) protocols in full field digital mammography polymethyl methacrylate (PMMA) phantoms are generally used. The possibility of using alternative materials has been investigated for digital breast tomosynthesis (DBT) because of the increased importance of scatter and more complex imaging geometries. We have investigated the use of PMMA in combination with polyethylene (PE) to simulate a range of typical breasts using a computation model of the imaging system. The scatter-to-primary ratios (SPRs) of both breast and phantom were also investigated and a difference up to 18% is found. Neglecting this difference in SPR in designing phantoms for DBT may lead to dosimetry errors. Taking into account estimated SPR values and relevant X-ray spectra, a combination of PMMA-PE slabs has been proposed to simulate typical breasts of thicknesses 30, 60 and 90 mm. The dosimetric error associated with using these phantoms for relevant X-ray spectra is less than 10%. © 2012 Springer-Verlag Berlin Heidelberg

Phantoms for quality control procedures of digital breast tomosynthesis

For quality control (QC) protocols in full field digital mammography polymethyl methacrylate (PMMA) phantoms are generally used. The possibility of using alternative materials has been investigated for digital breast tomosynthesis (DBT) because of the increased importance of scatter and more complex imaging geometries. We have investigated the use of PMMA in combination with polyethylene (PE) to simulate a range of typical breasts using a computation model of the imaging system. The scatter-to-primary ratios (SPRs) of both breast and phantom were also investigated and a difference up to 18% is found. Neglecting this difference in SPR in designing phantoms for DBT may lead to dosimetry errors. Taking into account estimated SPR values and relevant X-ray spectra, a combination of PMMA-PE slabs has been proposed to simulate typical breasts of thicknesses 30, 60 and 90 mm. The dosimetric error associated with using these phantoms for relevant X-ray spectra is less than 10%. © 2012 Springer-Verlag Berlin Heidelberg