Imaging the vascular network of the human spleen from immunostained serial sections

Figure 1: From left to right: One slide of an immunostained specimen of the human spleen stained for CD34 occurring endothelial cells of capillaries and larger blood vessels and in a small fibroblast population; the scan resolution is 25856×32000. Detail of the slide showing the stained capillaries. Detail of the iso-surface reconstruction from the aligned serial sections. Volume rendering of a further spleen immunostained for CD34, smooth muscle alpha actin and CD271 (first two targets colored brown, the latter one colored blue), both aligned with our technique. The spleen is one of the organs, where the micro-structure and the function on that level are not completely understood. It was for example only recently found that is has an open circulation, which distinguishes it from all other organs. Imaging the complete vascular network from the arteries to open-ended capillaries would greatly facilitate research in this area. The structure of such tissue is best uncovered using immunehistological staining. This can however only be applied to thin tissue sections and larger structures span several slices. Due to the deformation induced when cutting the specimen, standard registration algorithms cannot be used to merge the images into a volume. We propose a specialized matching algorithm to robustly determine corresponding regions in the images. After a rigid alignment of the scans, we use a cubic B-spline to deform and align the images. During this process we minimize the total deformation to produce as accurate results as possible