# The Use of Mixed Reality in Training Trainers--A Single-Centre Study
## 2 Literature Review  
[PERSON] et al. (2022) [11] reviewed 45 studies and assessed the validity rating of augmented reality (AR) in surgical training. In total, seven of these studies covered the use of a Microsoft HoloLens across the following specialties: urology, neurosurgery, gynaecology, general surgery and cardiothoracic surgery. HoloLens-assisted AR received a strong validity rating for surgical education and training, translating to a considerable reduction in error rates as well as an improvement in procedural times and economy of movement. Participants also reported increased self-perceived knowledge and confidence while enduring a relatively lesser cognitive load during task performance. Similarly, a randomised control trial (RCT) for orthopaedic training demonstrated that the use of AR led to a faster learning curve to achieve the same overall level of competency [12]. These findings have been further corroborated by [PERSON] et al. (2023) [13], where a review of 13 studies on the application of AR in simulation and training for hip surgery found it to be an extremely useful tool for pre-operative planning, reducing procedural times and surgical risk along with intraoperative radiation exposure. Augmented and mixed reality have also seen a rapid uptake in neurosurgical and spine training. [PERSON] et al. (2024) [14] reviewed eight studies, including three RCTs, that evaluated the performance of AR models for teaching procedures to neurosurgical trainees. These studies simulated procedures such as percutaneous spinal needle placement and percutaneous lumbar pedicle screw placement. Their results add to the evidence base that MR/AR technology enhances skill retention, preoperative planning and intraoperative execution, but that the main current limitation of such educational platforms is a lack of haptic feedback. In 2011, [PERSON] et al. [15] evaluated the use of an AR 3D simulator with haptic feedback as a training tool for thoracic pedicle screw placement and observed a 15% mean score improvement in performance accuracy, denoting the benefit of AR for training junior residents and surgeons. Moreover, a review by [PERSON] et al. (2021) [16] on the applications of AR in spine anatomy education found that while the technology potentially increases learner immersion and engagement, notable drawbacks include headaches, dizziness, and blurred vision. Not surprisingly, MR technology has increasingly been adopted across most surgical specialties. [PERSON] et al. (2023) [17] demonstrated higher test scores for residents in vascular surgery with MR-assisted teaching in comparison to traditional teaching methods. Similarly, a systematic review on the application of VR/AR in oral and maxillofacial surgery found 13 manuscripts on virtual education and training [18], while [PERSON] et al. (2022) [19] found 26 studies on virtual neurosurgery training. In 2022, a collaborative study between King's College London and Imperial College London involved the creation of a novel MR training curriculum for robot-assisted radical prostatectomy. Their results demonstrated that virtual surgical mentorship could be a feasible and cost-effective alternative to traditional training methods offering the potential to improve technical skills [20]. As discussed above, while MR's utility has been well demonstrated in teaching anatomy, surgical approaches, and interventions for patient care, whether its utility can be expanded across other aspects of education remains an unanswered question. Training the trainers (TOT) or residents as teachers (RATs) are often referred to as courses designed to inculcate the value of teaching amongst the junior trainees and doctors. The aim of these courses is to teach effective methods of teaching and communication to impart new knowledge. There is no available research or published articles that demonstrate the utility of incorporating MR in training the future trainers.