Image based registration between full x-ray and spot mammograms: analysis of registration accuracy in subgroups

The most typical type of cancer among women is breast cancer. Despite the crucial role that digital mammography plays in the early identification of breast cancer, many tumors could not be discriminated on mammography, especially in women with dense breast tissue. Contrast-enhanced magnetic resonance imaging (CE-MRI) of the breast is routinely used to find lesions that are invisible on mammography. MRI-guided biopsies must be used to further analyze these lesions. But MRI-guided biopsy is highly priced, time-consuming, and not frequently accessible. In our earlier work, we introduced a novel method using two methods of registration: biomechanical and image-based registration to transfer lesions from MRI to spot mammograms to allow x-ray guided biopsy. In this paper, we focus on enhancing and developing the image-based registration between full and spot mammograms and analyzing a correlation between the accuracy of our method and features such as views, location of lesion, breast area, size of lesion in each modality, and age. Results for 48 patients from the Medical University of Vienna are provided. The median target registration error is 20.9 mm and the standard deviation is 23.9 mm.