An innovative mixed reality approach for maxillofacial osteotomies and repositioning

Abstract

Craniomaxillofacial surgeries are performed using custom-made physical cutting guides and resin dental splints that present several drawbacks (e.g. time and cost required for their design and production). The literature commonly provides augmented/mixed reality (AR/MR) solutions for assisting maxillofacial osteotomies and repositioning without any interactive guide. This work proposes a new MR application, useful for osteotomy and repositioning, providing interactive, fast, and intuitive feedback to the surgeon, who is then supported in performing the bone fragment resection and replacement frame by frame. The proposed application speeds up the surgery and reduces under/overshooting errors. Moreover, the idea of integrating osteotomy and repositioning assistance in the same MR application is rarely found in the literature. It is an entirely novel approach to craniomaxillofacial surgery. The MR application has been designed with a three-button menu. The “App Start” calibrates the app, the “Osteotomy Mode” visualises the holograms of the cutting lines and drilling points, and the “Repositioning Mode” visualises the step-by-step real-time feedback to precisely support the surgeon placing the osteotomised bone fragment towards the final pre-planned position. The MR app has been developed in Unity and deployed on Microsoft HoloLens V2. A laboratory test bench was realised to validate the accuracy of the proposed MR-based approach. The validation protocol consists of two tasks to test the osteotomy and repositioning modes using a 3D-printed skull phantom. For osteotomy, the accuracy is 0.89 mm (genioplasty), 1.24 mm (maxillary osteotomy), 1.33 mm (orthognathic surgery), and 2.89 mm (mandibular angle osteotomy). For repositioning, the accuracy is 0.6 mm (anteroposterior deviation), 0.7 mm (mediolateral deviation), and 0.6° (angular deviation).

Fixation in Maxillofacial Surgery—Past, Present and Future: A Narrative Review Article

“…In contrast, AR overlays MRI or CT data onto the patient’s body during surgery, providing detailed insights into internal structures, which can help with precise incisions and visualizing critical anatomical features. 35 Ackermann et al introduced an AR application utilizing Microsoft HoloLens to aid pelvic osteotomy and fragment reorientation, enhancing visualization of the osteotomy cutting planes with marker-equipped mounts. 36 While AR and MR offer substantial benefits, they also face limitations, including tracking issues and hardware challenges.…”

Realistic Texture Mapping of 3D Medical Models Using RGBD Camera for Mixed Reality Applications

“…The use of these technologies in the industry is spreading, with applications being developed not only for entertainment and video games but also in many other areas, including medicine and surgery. The surgical areas where these technologies are being introduced are different: orthopaedic surgery [1][2][3][4][5][6], vascular surgery [7][8][9], oncology [10][11][12][13][14], neurosurgery [15][16][17][18] and maxillofacial surgery [19][20][21][22].…”