Visual Tracking vs Optical Tracking in Computer-Assisted Intervention

Computed-Assisted Intervention (CAI) aims to safely guide the surgeon during surgical interventions, which typically relies on Optical Tracking (OT) systems to provide the location of tools and instruments in a global reference frame, in real-time. Despite being very accurate, the existing OT systems have two main drawbacks: the difficulty of preserving lines-of-sight and the very high initial capital investment. We propose a new Visual Tracking (VT) system that effectively overcomes these issues by making use of 3D visual markers and an inexpensive monocular camera that can be located relatively close to the patient’s anatomy. Besides having these advantages, the new VT system also facilitates the navigation procedure by providing the guidance information in real-time using Augmented Reality. A thorough experimental evaluation demonstrates the validity of our approach, which is as accurate as the state-of-the-art OT system Optotrak Certus and better than Polaris Spectra [1]. It is also significantly easier to use since the requirement of the existence of a line-of-sight is always satisfied. Results obtained on an experiment that mimics a common procedure in the OR, as well as preliminary cadaver trials, confirm that the proposed VT system is clinically viable, making it clear that this is an important advance in the literature of tracking for CAI. Keywords—3D Registration, Computed-Assisted Intervention, Optical Tracking, Visual Tracking