Observer model optimization of a spectral mammography system

Erik Fredenberg; Magnus Åslund; Björn Cederström; Mats Lundqvist; Mats Danielsson

doi:10.1117/12.845480

18 March 2010 Observer model optimization of a spectral mammography system

Erik Fredenberg, Magnus Åslund, Björn Cederström, Mats Lundqvist, Mats Danielsson

Proceedings Volume 7622, Medical Imaging 2010: Physics of Medical Imaging; 762210 (2010) https://doi.org/10.1117/12.845480
Event: SPIE Medical Imaging, 2010, San Diego, California, United States

Abstract

Spectral imaging is a method in medical x-ray imaging to extract information about the object constituents by the material-specific energy dependence of x-ray attenuation. Contrast-enhanced spectral imaging has been thoroughly investigated, but unenhanced imaging may be more useful because it comes as a bonus to the conventional non-energy-resolved absorption image at screening; there is no additional radiation dose and no need for contrast medium. We have used a previously developed theoretical framework and system model that include quantum and anatomical noise to characterize the performance of a photon-counting spectral mammography system with two energy bins for unenhanced imaging. The theoretical framework was validated with synthesized images. Optimal combination of the energy-resolved images for detecting large unenhanced tumors corresponded closely, but not exactly, to minimization of the anatomical noise, which is commonly referred to as energy subtraction. In that case, an ideal-observer detectability index could be improved close to 50% compared to absorption imaging. Optimization with respect to the signal-to-quantum-noise ratio, commonly referred to as energy weighting, deteriorated detectability. For small microcalcifications or tumors on uniform backgrounds, however, energy subtraction was suboptimal whereas energy weighting provided a minute improvement. The performance was largely independent of beam quality, detector energy resolution, and bin count fraction. It is clear that inclusion of anatomical noise and imaging task in spectral optimization may yield completely different results than an analysis based solely on quantum noise.

Citation Download Citation

Erik Fredenberg, Magnus Åslund, Björn Cederström, Mats Lundqvist, and Mats Danielsson "Observer model optimization of a spectral mammography system", Proc. SPIE 7622, Medical Imaging 2010: Physics of Medical Imaging, 762210 (18 March 2010); https://doi.org/10.1117/12.845480

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available