Feature indexing in a database of digitized x-rays

We have the goal of developing computer algorithms for indexing a collection of digitized x-ray images for biomedical features important to researchers in the fields of osteoarthritis and vertebral morphometry. This indexing requires the segmentation of the image contents, identification of relevant anatomy in the segmented images, and classification of the identified anatomy into categories by which the image contents may be indexed. An example of the indexing detail that we have as a goal is, "disc space narrowing at vertebra location C5-6 ". This is a work in progress, with much current activity still in the segmentation step. We approach this segmentation as a hierarchical procedure with the distinctive regions of the image, including the general spine region, first being segmented at a gross level of detail, followed by a finer level segmentation of the spine region into individual vertebrae. In this paper we report on work done toward the gross level segmentation and also describe the image-level characteristics of one of the features targeted for the final indexing step.