Optimized simulation of breast anatomy for virtual clinical trials.

Virtual clinical trials (VCTs), computer simulations of clinical trials, can take many forms. In the field of breast imaging, VCTs often involve simulations of breast anatomy, which are used to produce simulated images of the breast with or without lesions. Our breast anatomy model consists of an array of voxels labeled to denote specific tissue types; the voxel labels are arrayed spatially so as to simulation various anatomic structures. Our most recent breast model includes numerous innovations in the anatomy simulation and data representation. The breast model has been revised in size and shape to better reflect the range of women seen clinically; the breast is divided into three breast regions (subcutaneous, interior, and posterior) with different rules to guide tissue arrangement; and tissue microstructure has been added to reflect a hierarchy of Cooper’s ligaments. The lesion simulation has been enhanced to support lesions with various shapes (e.g., spherical lesions with tapered periphery, circumscribed non-spherical lesions, and single or clustered microcalcifications) and lesion placement that follows the clinical prevalence. Finally, the data representation has been formalized to support large VCTs using the VCT pipeline software previously developed in our lab. These innovations have resulted in breast phantoms that are more realistic and more widely applicable.