This work proposes a simulation model involving subtraction of digital mammography images obtained at different X-ray beam levels of energy to aid the detection of breast malignant lesions. Absorption coefficients behavior of 3 main structures of clinical interest – adipose tissue, fiber glandular tissue and the typical carcinoma – as a function of the beam energy from a Mo X-ray tube was the basis to develop a computer simulation of the possible acquired images. The simulation has considered a typical compressed breast with 4.5cm in thickness, and variations of the carcinoma and glandular tissues thicknesses - 0.4 up to 2.0cm and 4.1 to 2.5cm, respectively - were evaluated as a function of the photons mean energy - 14 up to 25 keV, in the typical mammography energy range. Results have shown that: (a) if the carcinoma thickness is over 0.4cm, its detection may be feasible even masked by fiber tissue with exposures in the range of 19 to 25 keV; (b) for masked carcinoma with thickness in the range of 0.4-2.0cm, the proposed procedure can enhance it in the image resulting from the digital subtraction between images obtained at 14 and at 22 keV. Therefore such results indicate that this simulation procedure can be a useful tool in aiding the identification of possible missed malignant lesions which could not be detected in the typical exam, mainly considering dense breasts.

Date Published: 18 March 2015
PDF: 11 pages
Proc. SPIE 9412, Medical Imaging 2015: Physics of Medical Imaging, 94122T (18 March 2015); doi: 10.1117/12.2081188

Published in SPIE Proceedings Vol. 9412:
Medical Imaging 2015: Physics of Medical Imaging
Christoph Hoeschen; Despina Kontos, Editor(s)