A vascular analysis toolkit for intra-operative guide software

The vascular system analysis is a process, which involves all the different phases of an operation: diagnosis, pre-operative planning, intra-operative and follow-up evaluations. In the clinical practice the surgeon mentally reconstructs the 3-D shape of the vascular network from a set of 2-D images, which represents the cross-section or the projection of the vessels. Therefore the 3-D reconstructions of the vascular system, obtained from pre-operative images, must be mapped to those obtained from intra-operative and post-operative images. The aim of our project is to provide software, which facilitates such kind of evaluations. In this work we describe the core of the project, which consists in the creation of software for vascular tissue schematization. Thanks to the software developed we are able to schematize the vascular system through a hierarchical system of curves reflecting its topology. For each branch it will be possible to show the afferences and the section at each point. The symbolic representation described is essential for the analysis and registration of images of vascular systems. The method used for creating this symbolic representation is based on the ‘‘Voxel Coding’’ algorithm. Our group has modified the original formula of the program with the purpose of solving the malfunctions mentioned in literature and creating a stronger and faster version. Two vascular systems were analyzed: hepatic and cerebral The procedure has been experimented on a dataset of 6 patients, 4 of whom with pathologies affecting the morphology of the vascular system. In our experimentation the algorithm has provided a satisfactory schematization even in conditions of sudden variations in the vessels’ section and in the presence of segmentations with very irregular edges.