VolumetricOR: A New Approach to Simulate Surgical Interventions in Virtual Reality for Training and Education.

BACKGROUND: Surgical training is primarily carried out through observation during assistance or on-site classes, by watching videos as well as by different formats of simulation. The simulation of physical presence in the operating theatre in virtual reality might complement these necessary experiences. A prerequisite is a new education concept for virtual classes that communicates the unique workflows and decision-making paths of surgical health professions (i.e. surgeons, anesthesiologists and surgical assistants) in an authentic and immersive way. For this project, media scientists, designers and surgeons worked together to develop the foundations for new ways of conveying knowledge using virtual reality in surgery. MATERIALS AND METHOD: A technical workflow to record and present volumetric videos of surgical interventions in a photorealistic virtual operating room was developed. Situated in the virtual reality demonstrator called VolumetricOR, users can experience and navigate through surgical workflows as if they are physically present. The concept is compared with traditional video-based formats of digital simulation in surgical training. RESULTS: VolumetricOR let trainees experience surgical action and workflows (a) three-dimensionally, (b) from any perspective and (c) in real scale. This improves the linking of theoretical expertise and practical application of knowledge and shifts the learning experience from observation to participation. DISCUSSION: Volumetric training environments allow trainees to acquire procedural knowledge before going to the operating room and could improve the efficiency and quality of the learning and training process for professional staff by communicating techniques and workflows when the possibilities of training on-site are limited.

Real world usability analysis of two augmented reality headsets in visceral surgery.

Recent developments in the field of augmented reality (AR) have enabled new use cases in surgery. Initial set-up of an appropriate infrastructure for maintaining an AR surgical workflow requires investment in appropriate hardware. We compared the usability of the Microsoft HoloLens and Meta 2 head mounted displays (HMDs). Fifteen medicine students tested each device and were questioned with a variant of the System Usability Scale (SUS). Two surgeons independently tested the devices in an intraoperative setting. In our adapted SUS, ergonomics, ease of use, and visual clarity of the display did not differ significantly between HMD groups. The field of view (FOV) was smaller in the Microsoft HoloLens than the Meta 2 and significantly more study subjects (80% vs. 13.3%; P < 0.001) felt limited through the FOV. Intraoperatively, decreased mobility due to the necessity of an AC adapter and additional computing device for the Meta 2 proved to be limiting. Object stability was rated superior in the Microsoft HoloLens than the Meta 2 by our surgeons and lead to increased use. In summary, after examination of the Meta 2 and the Microsoft HoloLens, we found key advantages in the Microsoft HoloLens which provided palpable benefits in a surgical setting.

Teburu-Open source 3D printable bioreactor for tissue slices as dynamic three-dimensional cell culture models.

Three-dimensional tissue cultures are important models for the study of cell-cell and cell-matrix interactions, as well as, to investigate tissue repair and reconstruction pathways. Therefore, we designed a reproducible and easy to handle printable bioreactor system (Teburu), that is applicable for different approaches of pathway investigation and targeted tissue repair using human tissue slices as a three-dimensional cell culture model. Here, we definitively describe Teburu as a controlled environment to reseed a 500-µm thick decellularized human liver slice using human mesenchymal stroma cells. During a cultivation period of eight days, Teburu, as a semi-open and low consumption system, was capable to maintain steady pH and oxygenation levels. Its combination with additional modules delivers an applicability for a wide range of tissue engineering approaches under optimal culture conditions.