Unlike other widely used diagnostic and interventional techniques, endoscopy has a long history which has been characterized by continued improvements in utility and capability. Moving from simple tubes inserted in various natural orifices, through methods to light the distal anatomy, improving optical access with lenses, developing flexible structures, and then employing video, fiber optics, and
... [Show full abstract] solid state video cameras, endoscopy has developed in parallel with modern technology for almost two centuries. Here we discuss recent progress in augmenting endoscopy using visual guidance from 3D models based on pre-procedure images.