Efficient Collision Algorithm for the 3D Haptic Interaction with Solid Organs in Medical Environments

Using haptic (the sensing of touch) technology as an interface in medical and surgical procedures is a large interesting goal because of the benefits involved. This work presents a developed tool for evaluating the performance of a classic 2D-3D processing of a stack of medical preoperative images, and a new version of an efficient and simple algorithm for the integration of the haptic sense in a medical 3D environment generated from the 3D reconstruction. First of all, the developed tool for the 2D segmentation and 3D reconstruction is presented. The classical pipeline for surface 3D reconstruction is reviewed under a parametrical point of view. These parameters will play an important role in the analysis of the haptic behavior. Besides, all the parameters of the reconstruction are accessible and can be modified on-line during the reconstruction procedure. Later, the software architecture used for the integration of the haptic devices is described. The haptic rendering algorithm is detailed, including the collision detection algorithm (a simple ray-tracing scheme programmed using VTK capacities) that is used with the medical images. Finally, some results of the evaluation of the behavior of this algorithm are resumed.