1. A method for facilitating the detection of abnormalities in a breast, comprising: displaying an x-ray mammogram image of the breast to a user; displaying a thick-slice ultrasound image of the breast near said x-ray mammogram image, said thick-slice ultrasound image representing sonographic properties of a slab-like volume within the breast occupying less than the entire breast volume; and overlaying one of said ultrasound image or said x-ray mammogram image over the other to form a bimodal image, said bimodal image facilitating user perception of structures within the breast.