1. A method for in vivo identification of components in an interior region of a body comprising: using a medical imaging apparatus, obtaining an image of an interior region of a body, wherein the interior region includes components from a list of components, the image having pixel intensity information for individual pixels in the image; identifying a morphological structure in the image; for the individual pixels in the image, determining a distance from the pixel to the morphological structure; obtaining a first relationship correlating pixel intensity information with the components in the list of components; obtaining a second relationship correlating distance from the pixel to the morphological structure with the components in the list of components; and calculating a likelihood that the individual pixels in the image correspond to the components in the list of components using the first and second relationships, the pixel intensity information and the distance from the pixel to the morphological structure.