Human Middle Ear Anatomy Based on Micro-Computed Tomography and Reconstruction: An Immersive Virtual Reality Development

Background: For almost a decade, virtual reality (VR) has been employed in otology simulation. The realism and accuracy of traditional three-dimensional (3D) mesh models of the middle ear from clinical CT have suffered because of their low resolution. Although micro-computed tomography (micro-CT) imaging overcomes resolution issues, its usage in virtual reality platforms has been limited due to the high computational requirements. The aim of this study was to optimize a high-resolution 3D human middle ear mesh model suitable for viewing and manipulation in an immersive VR environment using an HTC VIVE VR headset (HTC and Valve Corporation, USA) to enable a seamless middle ear anatomical visualisation viewing experience in VR while preserving anatomical accuracy. Methods: A high-resolution 3D mesh model of the human middle ear was reconstructed using micro-CT data with 28 μm voxel resolution. The models were optimised by tailoring the surface model polygon counts, file size, loading time, and frame rate. Results: The optimized middle ear model and its surrounding structures (polygon counts reduced from 21 million polygons to 2.5 million) could be uploaded and visualised in immersive VR at 82 frames per second with no VR-related motion sickness reported. Conclusion: High-resolution micro-CT data can be visualized in an immersive VR environment after optimisation. To our knowledge, this is the first report on overcoming the translational hurdle in middle ear applications of VR.