Elastic registration of x-ray mammograms and three-dimensional magnetic resonance imaging data.

Major problems in treating breast cancer are the early detection of tumors and accurate biopsy of small volumes of breast (mamma) tissue. This report presents an elastic registration algorithm of two x-ray mammograms and a corresponding magnetic resonance imaging (MRI) volume. To cope with the soft tissue deformation of the breast during mammography, a two-dimensional model of breast deformation behavior is used as an elastic transformation. Normalized mutual information is employed as a measure of similarity. Regions of interest in the uncompressed x-ray mammograms are projected into the MRI volume to determine their three-dimensional origin.