BACKGROUND: Applications of robotics in daily life are becoming essential by creating new possibilities in different fields, especially in the collaborative environment. The potentials of collaborative robots are tremendous as they can work in the same workspace as humans. A framework employing a top-notch technology for collaborative robots will surely be worthwhile for further research.
OBJECTIVE: This study aims to present the development of a novel framework for the collaborative robot using mixed reality.
METHODS: The framework uses Unity and Unity Hub as a cross-platform gaming engine and project management tool to design the mixed reality interface and digital twin. It also uses the Windows Mixed Reality platform to show digital materials on holographic display and the Azure mixed reality services to capture and expose digital information. Eventually, it uses a holographic device (HoloLens 2) to execute the mixed reality-based collaborative system.
RESULTS: A thorough experiment was conducted to validate the novel framework for mixed reality-based control of a collaborative robot. This framework was successfully applied to implement a collaborative system using a 5-degree of freedom robot (xArm-5) in a mixed reality environment. The framework was stable and worked smoothly throughout the collaborative session. Due to the distributed nature of cloud applications, there is a negligible latency between giving a command and the execution of the physical collaborative robot.
CONCLUSIONS: Opportunities for collaborative robots in telerehabilitation and teleoperation are vital as in any other field. The proposed framework was successfully applied in a collaborative session, and it can also be applied in other similar potential applications for robust and more promising performance.

Background and objectives Mixed reality (MR) is one of the image processing technologies that allows the user to manipulate three-dimensional (3D) virtual images (hologram). The aim of this study was to evaluate the accuracy of MR-based pedicle screw (PS) placement using 3D spine models. Materials and methods Using the preoperative CT data of a patient with adolescent idiopathic scoliosis (AIS) who had undergone posterior spinal fusion in our hospital, a 3D-printed spine model was created. On the other hand, a 3D hologram of the same patient was automatically created using the preoperative CT data uploaded to the Holoeyes MD service website (Holoeyes Inc., Tokyo, Japan). Using a Magic Leap One® headset (Magic Leap Inc., Plantation, FL), the 3D hologram with lines of predetermined PS trajectories was superimposed onto the 3D-printed spine model and PS were inserted bilaterally along with the trajectory lines from T5 to L3. As a control, we used a readymade 3D spine model of AIS and inserted PS bilaterally with a freehand technique from T4 to L3. The rate of pedicle violation was compared between the MR-based and freehand techniques. Results A total of 22 and 24 PS were placed into the 3D-printed spine model of our patient and the readymade 3D spine model, respectively. The rate of pedicle violation was 4.5% (1/22 screws) in the MR-based technique and 29.2% (7/24 screws) in the freehand technique (P = 0.049). Conclusions We demonstrated a significantly lower rate of PS misplacement in the MR-based technique than in the freehand technique. Therefore, an MR-assisted system is a promising tool for PS placement in terms of feasibility, safety, and accuracy, warranting further studies including cadaveric and clinical studies.

This in vitro study aimed to compare the accuracy of dental implant placement in partially edentulous maxillary models using a mixed reality-based dynamic navigation (MR-DN) system to conventional static computer-assisted implant surgery (s-CAIS) and a freehand (FH) method.
Forty-five partially edentulous models (with teeth missing in positions #15, #16 and #25) were assigned to three groups (15 per group). The same experienced operator performed the model surgeries using an MR-DN system (group 1), s-CAIS (group 2) and FH (group 3). In total, 135 dental implants were placed (45 per group). The primary outcomes were the linear coronal deviation (entry error; En), apical deviation (apex error; Ap), XY and Z deviations, and angular deviation (An) between the planned and actual (post-surgery) position of the implants in the models. These deviations were computed as the distances between the stereolithographic (STL) files for the planned implants and placed implants captured with an intraoral scanner.
Across the three implant sites, the MR-DN system was significantly more accurate than the FH method (in XY, Z, En, Ap and An) and s-CAIS (in Z, Ap and An), respectively. However, S-CAIS was more accurate than MR-DN in XY, and no difference was found between MR-DN and s-CAIS in En.
Within the limits of this study (in vitro design, only partially edentulous models), implant placement accuracy with MR-DN was superior to that of FH and similar to that of s-CAIS.
In vitro, MR-DN showed greater accuracy in implant positioning than FH, and similar accuracy to s-CAIS: it could, therefore, represent a new option for the surgeon. However, clinical studies are needed to determine the feasibility of MR-DN.

Mixed reality (MxR) enables the projection of virtual three-dimensional objects into the user\'s field of view via a head-mounted display (HMD). This phantom model study investigated three different workflows for navigated common femoral arterial (CFA) access and compared it to a conventional sonography-guided technique as a control. A total of 160 punctures were performed by 10 operators (5 experts and 5 non-experts). A successful CFA puncture was defined as puncture at the mid-level of the femoral head with the needle tip at the central lumen line in a 0° coronary insertion angle and a 45° sagittal insertion angle. Positional errors were quantified using cone-beam computed tomography following each attempt. Mixed effect modeling revealed that the distance from the needle entry site to the mid-level of the femoral head is significantly shorter for navigated techniques than for the control group. This highlights that three-dimensional visualization could increase the safety of CFA access. However, the navigated workflows are infrastructurally complex with limited usability and are associated with relevant cost. While navigated techniques appear as a potentially beneficial adjunct for safe CFA access, future developments should aim to reduce workflow complexity, avoid optical tracking systems, and offer more pragmatic methods of registration and instrument tracking.

UNASSIGNED: Informed consent is a crucial aspect of modern medicine, but it can be challenging due to the complexity of the information involved. Mixed reality (MR) has emerged as a promising technology to improve communication. However, there is a lack of comprehensive research on the impact of MR on medical informed consent. The proposed research protocol provides a solid foundation for conducting future investigations and developing MR-based protocols that can enhance patients\' understanding and engagement in the decision-making process.
UNASSIGNED: This study will employ a randomized controlled trial design. Two arms will be defined: MR-assisted informed consent (MRaIC) as the experimental arm and conventional informed consent (CIC) as the control arm consent, with 52 patients in each group. The protocol includes the use of questionnaires to analyze the anxiety levels and the awareness of the procedure that the patient is going to perform to study the impact of MRaIC versus CIC before medical procedures.
UNASSIGNED: The study will evaluate the impact of MR on patients\' information comprehension, engagement during the process of obtaining informed consent, emotional reactions, and consent decisions. Ethical concerns will be addressed.
UNASSIGNED: This study protocol provides a comprehensive approach to investigate the impact of MR on medical informed consent. The findings may contribute to a better understanding of the effects of MR on information comprehension, engagement during the process of obtaining informed consent, psychological experience, consent decisions, and ethical considerations. The integration of MR technology has the potential to enhance surgical communication practices and improve the informed consent process.

The preparation and implementation of interdisciplinary oncological case reviews are time-consuming and complex. The variety of clinical and radiological information must be presented in a clear and comprehensible manner. Only if all relevant patient-specific information is demonstrated in a short time frame can well-founded treatment decisions be made on this basis. Mixed reality (MR) technology as a multimodal interactive user interface could enhance understanding in multidisciplinary collaboration by visualising radiological or clinical data. The aim of the work was to develop an MR-based software prototype for a head and neck tumour board (HNTB) to support clinical decision-making. The article describes the development phases and workflows in the planning and creation of a MR-based software prototype that were required to meet the multidisciplinary characteristics of a HNTB.

People with intellectual disability (ID) are often subject to motor impairments such as altered gait. As gait is a task involving motor and perceptive dimensions, perceptual-motor training is an efficient rehabilitation approach to reduce the risk of falls which grows with age. Virtual, augmented, and mixed reality are recent tools which enable interaction with 3D elements at different levels of immersion and interaction. In view of the countless possibilities that this opens, their use for therapeutic purposes is constantly increasing. Therefore, the aim of this study was to investigate the influence a mixed reality activity could have on motor and cognitive abilities in eighteen adults with intellectual disability. For three months, once a week, they had around 20 min to pop virtual balloons with a finger using a Microsoft HoloLens2® head-mounted mixed-reality device. Motor skills were assessed through gait analysis and cognitive abilities were measured with the Montréal Cognitive Assessment. Both walking speed and cognitive score increased after training. In conclusion, this study demonstrates that mixed reality holds potential to get used for therapeutic purposes in adults with ID.

BACKGROUND: Virtual reality is emerging as an important component of medical education. Although the benefits of virtual reality are apparent, the optimal strategy to orient to or differentiate learners in the virtual space have not been delineated. The purpose of this study was to investigate the relationships between demographic variables, social variables, and self-perceived comfort with technology to performance on a standardized non-medical virtual reality experience.
METHODS: This observational study was performed at the International Meeting on Simulation in Healthcare in 2022. This conference includes medical and non-medical attendees. Participants provided demographic information and participated in a scored non-medical VR experience due to the heterogeneity of the sample. Participants then completed a System Usability Index and NASA Task Load Index form. Participants were dividedintolow scoring, medium scoring, and high scoring groups according to their final game score for further analysis.
RESULTS: 95 participants were included in final analysis. 55 (57.9%) of participants had prior virtual reality experience. Higher scores were associated with younger age (11.09, p < 0.001), identifying as male (11.09, p < 0.001), and a higher frequency of playing video games in the past (18.96, p < 0.001). The high score group was more likely to report comfort with virtual reality (6.29, p = 0.003) as well as comfort with new technology (4.61, p = 0.012). NASA Task Load Index scores trended down and System Usability Index scores trended up with increasing score. Being a nurse was a positive predictor of a higher score when compared to physicians in the multivariate analysis.
CONCLUSIONS: Performance during an immersive virtual reality experience was most closely related to age, gender, and frequency of playing video games. Self-perceived comfort with virtual reality was more predictive of score than prior virtual reality experience.

This study aimed to rigorously assess the accuracy of mixed-reality neuronavigation (MRN) in comparison with magnetic neuronavigation (MN) through a comprehensive phantom-based experiment. It introduces a novel dimension by examining the influence of blue-green light (BGL) on MRN accuracy, a previously unexplored avenue in this domain.
Twenty-nine phantoms, each meticulously marked with 5-6 fiducials, underwent CT scans as part of the navigation protocol. A 3D model was then superimposed onto a 3D-printed plaster skull using a semiautomatic registration process. The study meticulously evaluated the accuracy of both navigation techniques by pinpointing specific markers on the plaster surface. Precise measurements were then taken using digital calipers, with navigation conducted under three distinct lighting conditions: indirect white light (referred to as no light [NL]), direct white light (WL), and BGL. The research enlisted two operators with distinct levels of experience, one senior and one junior, to ensure a comprehensive analysis. The study was structured into two distinct experiments (experiment 1 [MN] and experiment 2 [MRN]) conducted by the two operators. Data analysis focused on calculating average and median values within subgroups, considering variables such as the type of lighting, precision, and recording time.
In experiment 1, no statistically significant differences emerged between the two operators. However, in experiment 2, notable disparities became apparent, with the senior operator recording longer times but achieving higher precision. Most significantly, BGL consistently demonstrated a capacity to enhance accuracy in MRN across both experiments.
This study demonstrated the substantial positive influence of BGL on MRN accuracy, providing profound implications for the design and implementation of mixed-reality systems. It also emphasized that integrating BGL into mixed-reality environments could profoundly improve user experience and performance. Further research is essential to validate these findings in real-world settings and explore the broader potential of BGL in a variety of mixed-reality applications.

The placement of a ventricular catheter, that is, an external ventricular drain (EVD), is a common and essential neurosurgical procedure. In addition, it is one of the first procedures performed by inexperienced neurosurgeons. With or without surgical experience, the placement of an EVD according to anatomical landmarks only can be difficult, with the potential risk for inaccurate catheter placement. Repeated corrections can lead to avoidable complications. The use of mixed reality could be a helpful guide and improve the accuracy of drain placement, especially in patients with acute pathology leading to the displacement of anatomical structures. Using a human cadaveric model in this feasibility study, the authors aimed to evaluate the accuracy of EVD placement by comparing two techniques: mixed reality and freehand placement.
Twenty medical students performed the EVD placement procedure with a Cushing\'s ventricular cannula on the right and left sides of the ventricular system. The cannula was placed according to landmarks on one side and with the assistance of mixed reality (Microsoft HoloLens 2) on the other side. With mixed reality, a planned trajectory was displayed in the field of view that guides the placement of the cannula. Subsequently, the actual position of the cannula was assessed with the help of a CT scan with a 1-mm slice thickness. The bony structure as well as the left and right cannula positions were registered to the CT scan with the planned target point before the placement procedure. CloudCompare software was applied for registration and evaluation of accuracy.
EVD placement using mixed reality was easily performed by all medical students. The predefined target point (inside the lateral ventricle) was reached with both techniques. However, the scattering radius of the target point reached through the use of mixed reality (12 mm) was reduced by more than 54% compared with the puncture without mixed reality (26 mm), which represents a doubling of the puncture accuracy.
This feasibility study specifically showed that the integration and use of mixed reality helps to achieve more than double the accuracy in the placement of ventricular catheters. Because of the easy availability of these new tools and their intuitive handling, we see great potential for mixed reality to improve accuracy.