Assessment, validation, and visualisation of bony changes in crano-facial surgery

Mid-facial distraction osteogenesis is a novel promising method to correct severe mid-facial hypoplasia and retrognathia. Although aesthetic improvements are obvious, the analysis of three-dimensional bony changes created through distraction was impossible so far. Now, we present a tool chain employing voxel based registration and 3D visualisation to assess and analyse the structural changes induced by the treatment based on the routinely acquired preand post-operative CT images. A landmark based validation of the voxel-based registration provides measures to rate the obtained results. Application to real patient data demonstrates that this tool chain can help to get a better perception of the complex three dimensional deformations of the skull during treatment.