Introduction: Mixed reality (MR) is a novel tool that is expected to assist medical imaging. A wearable MR device allows its wearer to view holographic 3-dimensional (3D) images projected in the real world. This can assist the wearers in linking their anatomical knowledge with a real human body, which is vital when conducting ultrasound (US) examinations. Thus, MR technology could lead to more efficient US training for beginners. We analyzed the utility of holographic 3D abdominal organ model projection using a MR device for medical students receiving renal US training.
Methods: From August to September 2019, participants with no prior US experience were recruited from Tokyo Medical and Dental University, 4th grade. After basic renal US training, participants repeated the same US training protocol but using the head-mounted HoloLens (Microsoft, Redmond, WA, USA) MR device to superimpose a holographic 3D abdominal organ model on to the US subject’s body (Figure). The 3D organ model was developed from computed tomography images using the Synapse Vincent (Fuji Medical Systems, Tokyo, Japan) and HoloEyesXR (Holoeyes, Tokyo, Japan) software. Following completion of each training protocol, participants completed an anonymous questionnaire composed of 0-10 scale and open-ended questions assessing the utility of the training.
Results: 15 participants were enrolled in this study and they all completed the questionnaires. The median (range) age of the participants was 21 (21-23) years. The 3D organ model projection significantly improved assessment scores regarding the following 7 elements; anatomical acquisition, renal hilum inspection, self-efficacy to detect the kidney, self-efficacy to conduct renal US, ease of kidney detection, learning effect of the training, and recommendation to other students (p<0.05 for all). The most frequent answer to the open-ended question regarding why they thought MR technology was useful for US training was, “contribution to understanding the positional relationship between the abdominal organs.” (13/15, 87%).
Conclusions: Holographic 3D organ model projection from a wearable MR computer facilitates renal US training of medical students. Source of