First clinical tests with the augmented reality system INPRES.

In this paper we present the results of the first patient experiment in craniofacial surgery of the INPRES system - an augmented reality system on the basis of a tracked see-through head-mounted display.

Evaluation of INPRES--Intraoperative Presentation of surgical planning and simulation results.

In this paper we present fundamental results of the first evaluation of INPRES in a laboratory environment. While the system itself--an HMD-based approach for intraoperative augmented reality in head and neck surgery--has been described elsewhere several times, this paper will focus on methods and outcome of recently accomplished test procedures.

Risk reduction in craniofacial surgery using computer-based modeling and intraoperative immersion.

We present a two-stage concept for risk reduction in craniofacial surgery, consisting of preoperative risk modeling and intraoperative risk reduction. Preoperatively it is important to find and to visualize risk sources in order to minimize them. Our risk model is composed by superimposition of an isotropic risk potential and an anisotropic tissue field constituent. It is being applied to preoperative planning and simulation of craniofacial surgeries, for example to determine an access path with least overall risk value. In the operation room risks arise mainly from the absence of preoperative planning and simulation data in the operation field. We use a see-through head-mounted display to optimize this situation in order to allow the surgeon to maintain accuracy in the whole process of computer aided surgery. Main steps of the intraoperative immersion are optical tracking of the surgeon wearing the head-mounted display and of the patient, registration of preoperatively calculated planning data with the patient and visualization of the data within the glasses.