Computer-aided Medicine and Surgery

This special issue of Computer Methods in Biomechanics and Biomedical Engineering (CMBBE) contains selected contributions from works presented at the 6th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering held in Madrid in February 2004 during a minisymposium on “Computer aided medicine and surgery, medical imaging and medical informatics”. This symposium was aimed at presenting the state of the art and at discussing developments in modelling and simulations applied to medicine and surgery. The topics of the seven papers illustrate some current research trends in various fields, from computer-aided diagnosis, virtual endoscopy, and functional testing to treatment planning and training of minimally invasive therapies. Image processing, computer graphics and virtual reality applied to medicine and surgery, modelling and simulation of the behaviour of biological tissues, and robotics are all involved in advanced medical techniques. Physiological models illustrate the joint research involving at least investigators in biomechanics, applied mathematics, medical image processing, and infographics. The study of air flow in models of the tracheobronchial tree in the normal and the pathological states presented in this special issue is representative of the medical needs in computer tools. However, a lot of works remain to be done in this research area to provide robust and quick results. Soft tissue deformation must be taken into account not only during image-guided interventions, but also to provide reliable elements for the medical check-up and the choice of the therapy. Neighbouring organs, compartments of a conduit network interact between them. Modelling and simulations require coupling, and, due to the increase in complexity, to fast solving. Investigations are carried out to develop multiscale modelling associated with interactions between elements of a set, and within the element, with the physiological processes involved at the various scales, from the biochemical reactions to the organ. The image processing reconstructs not only the surface of the organ of interest, but also the internal wetted surface of a vessel network. Current endoscopies are quite invasive whereas efficient virtual endoscopies can be performed, following the trajectory of the virtual endoscope on the screen, or even to select the path between a starting point anf the final destination. Such a facility is particularly convenient for the complex tracheobronchial tree with its short bronchi separated by asymmetrical non-planar junctions. Shape optimization can be applied to the design of implantable medical devices or of medical instruments, such as the coloscope. A better visualisation of the targeted organs with its irrigation vessels is necessary for treatment planning, especially in surgery to limit the bleeding risks and to provide incision routes. Moreover, the blood flow can affect the therapy efficiency, particularly the cryotherapy and the radiofrequency ablation of the liver tumors. Accurate simulations of propagating heat front needs anisotropic remeshing. Optimal positioning of the probes for a given tumor localization in a given patient is needed to enhance the therapy effects and to minimize the damage of the healthy tissues. Computer-assisted surgery rely on automatically reconstructed patient-specific models of anatomical structures. For this purpose, existing generic models can be used as input data. An example of such a strategy is given with the maxillofacial surgery. Computer tools are thus aimed not only at planning the treatment but also at predicting the consequences of the interventions. To conclude, we thank the reviewers, the scientific editorial board, and the publishing office for the time spent for this special issue.