Gaining an in-depth understanding of the structure of software systems can be overwhelming, time-consuming, and unappealing. Since people play a key role in software development, human factors, such as motivation, must be considered when designing software development tools. We investigated this concept by using “gamification” for software visualization. We developed a gamified visualization tool for object-oriented software architectures, added gamification elements using a user-centered design approach, and evaluated it based on qualitative feedback from software developers. Our results suggest that gamification meaningfully enhances software understanding via visualization. However, further design iterations are needed to improve gamified visualization, as well as a quantitative study to evaluate it.

Training communication with patients is an important aspect of medical education around the world. The general complexity of communication and specifically communication with patients can be practiced with actors. However, access to this training method is restricted by limited availability of actors, complex organization of time schedules, and the need of physical training space. Our work explores the benefits of using a serious game for training patient-physician communication. The game implements the SPIKES communication model to efficiently and effectively structure such conversations. SPIKES is used for example to deliver bad news or inform patients about medical treatment plans. This paper presents the results of a first study with medical students evaluating acceptance and the educational benefit of the game as part of the communication training.

Stereotypes support a high-level software comprehension by implying roles and responsibilities of classes in software systems. We propose the idea of using stereotypes as design patterns for serious games to enhance object oriented software comprehension. These design patterns can reduce the complexity of software systems and encode software knowledge into game mechanics. We provide examples of possible game mechanics and discuss the application of the proposed design patterns.

Virtual Reality (VR) has been proposed as an immersive medium in psychotherapy for supporting the treatment of various phobias or behavioral disorders. In classic therapy of mental disorders as well as to reduce stress, various relaxation methods are used. This includes guided imagery, i.e. verbally describing peaceful scenes of nature to the patient. This paper presents a virtual relaxation environment for portable VR systems that has been designed on the basis of theories and research in nature and environmental psychology. The aim of the system is to induce relaxation. We further report on the evaluation of a study design to prepare the system for experiments with patients, measuring relaxation by the change of affective state as well as attention restoration.

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.

Port position in minimally invasive surgeries is chosen to minimize the lesion of tissue and maximize the movability for endoscopic instruments. In this study, we present an evaluation of the potential of a 3D contextual in-situ visualization of the anatomic target region to help surgeons for three different surgical procedures decide where best to create ports and incisions to enable the insertion of a specific set of instruments.

Medical augmented reality (AR) has been widely discussed within the medical imaging as well as computer aided surgery communities. Different systems for exemplary medical applications have been proposed. Some of them produced promising results. One major issue still hindering AR technology to be regularly used in medical applications is the interaction between physician and the superimposed 3-D virtual data. Classical interaction paradigms, for instance with keyboard and mouse, to interact with visualized medical 3-D imaging data are not adequate for an AR environment. This paper introduces the concept of a tangible/controllable Virtual Mirror for medical AR applications. This concept intuitively augments the direct view of the surgeon with all desired views on volumetric medical imaging data registered with the operation site without moving around the operating table or displacing the patient. We selected two medical procedures to demonstrate and evaluate the potentials of the Virtual Mirror for the surgical workflow. Results confirm the intuitiveness of this new paradigm and its perceptive advantages for AR-based computer aided interventions.

Augmented reality (AR) for preoperative diagnostics and planning, intra operative navigation and postoperative follow-up examination has been a topic of intensive research over the last two decades. However, clinical studies showing AR technology integrated into the real clinical environment and workflow are still rare. The incorporation of an AR system as a standard tool into the real clinical workflow has not been presented so far. This paper reports on the strategies and intermediate results of the ARAV - augmented reality aided vertebroplasty project that has been initiated to make an AR system based on a stereo video see-through head mounted display that is permanently available in the operating room (OR).

In this paper we present the evaluation of a virtual mirror used as a navigational tool within a medical augmented reality (AR) system for laparoscopy. 12 surgeons of our clinical partner participated in an experiment to evaluate whether laparoscope augmentation extended by a virtual mirror is useful for improved perception of complex structures. Such complex structures are encountered for instance in laparoscopic resection of tumor affected liver tissue. The blood vessels supplying the tumor have to be cut and closed before tumorous tissue can be removed. A laparoscopic camera and an optical tracking system allow for the visualization of visualized medical volumetric data registered with the real anatomy. Previously injected contrast agent provides an accentuation of blood vessels within the visualization. For evaluating the suitability of a virtual mirror to support the mentioned procedure, we designed a phantom consisting of wooden branches simulating the structure of blood vessel trees. Quantitative results of the experiment show the advantage of a mirror in certain cases, when blood vessels cannot be directly seen from the camera point of view due to self-occlusion of the structure. Results of a questionnaire filled out by the surgeons after the experiments confirm the acceptance of AR technology for particular medical procedures.

The need to improve medical diagnosis and reduce invasive surgery is dependent upon seeing into a living human system. The use of diverse types of medical imaging and endoscopic instruments has provided significant breakthroughs, but not without limiting the surgeon's natural, intuitive and direct 3D perception into the human body. This paper presents a method for the use of augmented reality (AR) for the convergence of improved perception of 3D medical imaging data (mimesis) in context to the patient's own anatomy (in-situ) incorporating the physician's intuitive multi- sensory interaction and integrating direct manipulation with endoscopic instruments. Transparency of the video images recorded by the color cameras of a video see-through, stereoscopic head- mounted-display (HMD) is adjusted according to the position and line of sight of the observer, the shape of the patient's skin and the location of the instrument. The modified video image of the real scene is then blended with the previously rendered virtual anatomy. The effectiveness has been demonstrated in a series of experiments at the Chirurgische Klinik in Munich, Germany with cadaver and in-vivo studies. The results can be applied for designing medical AR training and educational applications.

A major roadblock for using augmented reality in many medical and industrial applications is the fact that the user cannot take full advantage of the 3D virtual data. This usually requires the user to move the virtual object, which disturbs the real/virtual alignment, or to move his head around the real objects, which is not always possible and/or practical. This problem becomes more dramatic when a single camera is used for monitor based augmentation, such as in augmented laparoscopic surgery. In this paper we introduce an interaction and 3D visualization paradigm, which presents a new solution to this old problem. The interaction paradigm uses an interactive virtual mirror positioned into the augmented scene, which allows easy and complete interactive visualization of 3D virtual data. This paper focuses on the exemplary application of such visualization techniques to laparoscopic interventions. A large number of such interventions aims at regions inside a specific organ, e.g. blood vessels to be clipped for tumor resection. We use high-resolution intra-operative imaging data generated by a mobile C-arm with cone-beam CT imaging capability. Both the C-arm and the laparoscope are optically tracked and registered in a common world coordinate frame. After patient positioning, port placement, and carbon dioxide insufflation, a C-arm volume is reconstructed during patient exhalation and superimposed in real time on the laparoscopic live video without any need for an additional patient registration procedure. To overcome the missing perception of 3D depth and shape when rendering virtual volume data directly on top of the organ's surface view, we introduce the concept of a laparoscopic virtual mirror: A virtual reflection plane within the live laparoscopic video, which is able to visualize a reflected side view of the organ and its interior. This enables the surgeon to observe the 3D structure of, for example, blood vessels by moving the virtual mirror within the augmented monocular view of the laparoscope.