1. A system comprising: (a) a receiver circuit configured to receive (i) at least two reference images, each reference image of the at least two reference images including a respective landmark subsurface feature of a mammalian body part, and (ii) data indicative of a respective spatial relationship among each respective landmark subsurface feature of the at least two reference images; (b) a coordinate analysis circuit configured to determine a common frame of reference at least partially based on a landmark subsurface feature of the mammalian body part included in a reference image of the at least two reference images; (c) a registration circuit configured to register the respective landmark subsurface feature of the mammalian body part included in each reference image of the at least two reference images, the registration at least partially based on the determined common frame of reference and on the data indicative of a respective spatial relationship among each respective landmark subsurface feature of the at least two reference images; and (d) a computer-readable media configured to maintain informational data corresponding to the registration of the respective landmark subsurface feature of the mammalian body part included in each reference image of the at least two reference images.