Immersive 3D Medical Visualization in Virtual Reality using Stereoscopic Volumetric Path Tracing

Scientific visualizations using physically-based lighting models play a crucial role in enhancing both image quality and realism. In the domain of medical visualization, this trend has gained significant traction under the term cinematic rendering (CR). It enables the creation of 3D photorealistic reconstructions from medical data, offering great potential for aiding healthcare professionals in the analysis and study of volumetric datasets. However, the adoption of such advanced rendering for immersive virtual reality (VR) faces two main limitations related to their high computational demands. First, these techniques are frequently used to produce pre-recorded videos and offline content, thereby restricting interactivity to pre-defined volume appearance and lighting settings. Second, when deployed in head-tracked VR environments they can induce cyber-sickness symptoms due to the disturbing flicker caused by noisy Monte Carlo renderings. Consequently, the scope for meaningful interactive operations is constrained in this modality, in contrast with the versatile capabilities of classical direct volume rendering (DVR). In this work, we introduce an immersive 3D medical visualization system capable of producing photorealistic and fully interactive stereoscopic visualizations on head-mounted display (HMD) devices. Our approach extends previous linear regression denoising to enable real-time stereoscopic cinematic rendering within AR/VR settings. We demonstrate the capabilities of the resulting VR system, like its interactive rendering, appearance and transfer function editing.