Multi-volume rendering using depth buffers for surgical planning in virtual reality.

Area of Science:

• Medical visualization
• Computer graphics
• Surgical planning

Background:

• Virtual Reality (VR) offers intuitive navigation of volumetric medical data, enhancing depth perception for surgical planning.
• Ray marching volume rendering provides superior detail and accuracy compared to traditional mesh-based methods, eliminating the need for segmentation and meshing.
• Rendering multiple intersecting volumes in VR presents a challenge due to performance demands.

Purpose of the Study:

• To develop and evaluate a novel multi-volume rendering technique for VR surgical planning.
• To maintain high update rates for a comfortable user experience in VR environments with complex volumetric data.
• To enable dynamic manipulation of original volumetric data without compromising rendering performance.

Main Methods:

• A rough, ad hoc segmentation is performed using a motion-tracked controller to separate volumes.
• Volumes are rendered in consecutive passes, with ray lengths stored in the depth buffer for accurate occlusion.
• This method avoids surface mesh extraction, focusing on efficient rendering of sub-volumes.

Main Results:

• The multi-volume renderer successfully avoids dropped frames at 90 frames per second, ensuring a comfortable VR experience.
• The approach supports rendering over twenty individual volumes, demonstrating scalability for complex surgical cases.
• Performance was evaluated across three distinct use cases and datasets.

Conclusions:

• The proof-of-concept implementation validates the feasibility of VR-based surgical planning systems.
• Dynamic manipulation of volumetric data is achievable without sacrificing rendering performance or user experience.
• This technique enhances the potential of VR for complex surgical planning and visualization.