Shadow rendering for improved volumetric visualization in real time 4D-OCT

Progress in swept source laser technology and graphics processing unit (GPU) realized live volumetric OCT (4D-OCT). Shadowing is one of advanced rendering techniques to add more realistic spatial comprehension to objects in space. We developed and implemented a shadow extended ray casting technique to be applied for real time 4D-OCT, using both a SS-OCT and SD-OCT. Our results show that the shadow extended ray casting technique achieves greater threedimensionality in volumetric data through self-shadowing, and also improves depth perception of objects in space because of planar shadows projected onto a surface. The shadowing algorithm was implemented using texture memory of the GPU, which achieves surgeon-interactive surgical guidance of ophthalmic microsurgery.

[1]  B. Bouma,et al.  Handbook of Optical Coherence Tomography , 2001 .

[2]  Joseph A. Izatt,et al.  Real-time corneal segmentation and 3D needle tracking in intrasurgical OCT , 2018, Biomedical optics express.

[3]  Kang Zhang,et al.  Real-time 4D signal processing and visualization using graphics processing unit on a regular nonlinear-k Fourier-domain OCT system , 2010, Optics express.

[4]  Kevin Wong,et al.  Graphics processing unit accelerated optical coherence tomography processing at megahertz axial scan rate and high resolution video rate volumetric rendering , 2013, Journal of biomedical optics.

[5]  Beop-Min Kim,et al.  High-resolution, dual-depth spectral-domain optical coherence tomography with interlaced detection for whole-eye imaging. , 2016, Applied optics.

[6]  Rüdiger Westermann,et al.  Acceleration techniques for GPU-based volume rendering , 2003, IEEE Visualization, 2003. VIS 2003..

[7]  Ralf Sarlette,et al.  Exploitation of human shadow perception for fast shadow rendering , 2005, APGV '05.

[8]  G. Ripandelli,et al.  Optical coherence tomography. , 1998, Seminars in ophthalmology.

[9]  Nelson L. Max,et al.  Optical Models for Direct Volume Rendering , 1995, IEEE Trans. Vis. Comput. Graph..

[10]  Timo Ropinski,et al.  Efficient Shadows for GPU-based Volume Raycasting , 2011 .

[11]  Yifan Jian,et al.  GPU accelerated OCT processing at megahertz axial scan rate and high resolution video rate volumetric rendering , 2013, Photonics West - Biomedical Optics.

[12]  Youngwoon Choi,et al.  Full ocular biometry through dual-depth whole-eye optical coherence tomography , 2018, 2018 Conference on Lasers and Electro-Optics (CLEO).

[13]  Anthony N Kuo,et al.  Enhanced volumetric visualization for real time 4D intraoperative ophthalmic swept-source OCT , 2016, Biomedical optics express.

[14]  Wolfgang Wieser,et al.  Multi-megahertz OCT: High quality 3D imaging at 20 million A-scans and 4.5 GVoxels per second. , 2010, Optics express.

[15]  François X. Sillion,et al.  A Survey of Real‐time Soft Shadows Algorithms , 2003, Comput. Graph. Forum.

[16]  Alois Knoll,et al.  Needle Segmentation in Volumetric Optical Coherence Tomography Images for Ophthalmic Microsurgery , 2017 .