Education of anatomy is a challenging but crucial element in educating medical professionals, but also for general education of pupils. Our research group has previously developed a prototype of an Augmented Reality (AR) magic mirror which allows intuitive visualization of realistic anatomical information on the user. However, the current overlay is imprecise as the magic mirror depends on the skeleton output from Kinect. These imprecisions affect the quality of education and learning. Hence, together with clinicians we have defined bone landmarks which users can touch easily on their body while standing in front of the sensor. We demonstrate that these landmarks allow the proper deformation of medical data within the magic mirror and onto the human body, resulting in a more precise augmentation.

This paper describes first steps towards a Superman-like X-ray vision where a brain-computer interface (BCI) device and a gaze-tracker are used to allow the user controlling the augmented reality (AR) visualization. A BCI device is integrated into two medical AR systems. To assess the potential of this technology first feedback from medical doctors is gathered. While in this pilot study not the full range of available signals but only electromyographic signals are used, the medical doctors provided very positive feedback on the use of BCI for medical AR.

We present an augmented reality magic mirror for teaching anatomy. The system uses a depth camera to track the pose of a user standing in front of a large display. A volume visualization of a CT dataset is augmented onto the user, creating the illusion that the user can look into his body. Using gestures, different slices from the CT and a photographic dataset can be selected for visualization. In addition, the system can show 3D models of organs, text information and images about anatomy. For interaction with this data we present a new interaction metaphor that makes use of the depth camera. The visibility of hands and body is modified based on the distance to a virtual interaction plane. This helps the user to understand the spatial relations between his body and the virtual interaction plane.

The mirracle system extends the concept of an Augmented Reality (AR) magic mirror to the visualization of human anatomy on the body of the user. Using a medical volume renderer a CT dataset is augmented onto the user. By a slice based user interface, slice from the CT and an additional photographic dataset can be selected.

The paper presents a user study investigating perceptual effects of a virtual mirror being used as a tangible interactive tool in a medical Augmented Reality scenario. In particular, we evaluated whether an additional perspective provided by the virtual mirror supports instrument guidance in terms of precision and straightness. 31 participants were asked to navigate an endoscopic instrument in a simulated minimally invasive port setting. Results show a significant higher precision of instrument guidance when a virtual mirror provides additional views of the target region.

Visual discomfort is a major problem for head-mounted displays and other stereo displays. One effect that is known to reduce visual comfort is double vision, which can occur due to high disparities. Previous studies suggest that adding artificial out-of-focus blur increases the fusional limits, where the left and right image can be fused without double vision. We investigate the effect of adding artificial out-of-focus blur on visual discomfort using two different setups. One uses a stereo monitor and an eye tracker to change the depth of focus based on the gaze of the user. The other one uses a video-see through head mounted display. A study involving 18 subjects showed that the viewing comfort when using blur is significantly higher in both setups for virtual scenes. However we can not confirm without doubt that the higher viewing comfort is only related to an increase of the fusional limits, as many subjects reported that double vision did not occur during the experiment. Results for additional photographed images that have been shown to the subjects were less significant. A first prototype of an AR system extracting a depth map from stereo images and adding artificial out-of-focus blur is presented.

Ultrasound (US) is a medical imaging modality which is extremely difficult to learn as it is user-dependent, has low image quality and requires much knowledge about US physics and human anatomy. For training US we propose an Augmented Reality (AR) ultrasound simulator where the US slice is simulated from a CT volume. The location of the US slice inside the body is visualized using contextual in-situ techniques. We also propose advanced methods how to use an AR simulator for training.

In our poster presentation at ISMAR '04, we proposed the idea of an AR training solution including capture and 3D replays of subtle movements. The crucial part missing for realizing such a training system was an appropriate way of synchronizing trajectories of similar movements with varying speed in order to simultaneously visualize the motion of experts and trainees, and to study trainees' performances quantitatively. We review the research from different communities on synchronization problems of similar complexity. We give a detailed description of the two most applicable algorithms. We then present results using our AR based forceps delivery training system and therefore evaluate both methods for synchronization of experts' and trainees' 3D movements. We also introduce the first concepts of an online synchronization system allowing the trainee to follow movements of an expert and the experts to annotate 3D trajectories for initiation of actions such as display of timely information. A video demonstration provides an overview of the work and a visual idea of what users of the proposed system could observe through their video-see through HMD.