A Real Time, Ray-Traced, Global Illumination, High Dynamic Range Image Shaded, Three Dimensional Visualization System for Segmentational Data in Ophthalmology

Abstract

Purpose: : To create a ray-traced real time three dimensional visualization system for segmentational data in ophthalmology which uses high dynamic range images (HDRI) for global illumination (GI), and is independent of imaging hardware used to obtain the data, as well as independent of the software platform being used on the reviewing station.

Methods: : Segmentational data was collected from two different spectral domain optical coherence tomography (SD-OCT) systems as well as from cranial magnetic resonance imaging (MRI) of the optic nerve pathway, confocal corneal microscopy (CCF), and cryo-sections (CS) of retinal tissue. Using the C/C++ based computer scripting languages C.O.F.F.E.E and X.P.R.E.S.S.O (Maxon Inc.), several interactive scripts and expressions were developed to translate the segementational data sets previously acquired into objects which could be rendered in the ray-traced rendering program Cinema 4DXL 11.5 (Maxon Inc). Additional scripts were developed to bake HDRI shading directly into the data, allowing for OPENGL real time interactive GI rendering of the data sets using conventional graphics chips. The visualization system was seen to be equally functional on standard personal computers running MAC OS 10.5, Windows XP, Windows Vista, or Linux.

Results: : It was possible to develop a ray-traced real time HDRI shaded 3D visualization system for SD-OCT, MRI, CFM, and CS. The addition of HDRI shading increased the clarity of the visualizations dramatically, in comparison to conventional commercially available visualization systems.

Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • image processing • imaging/image analysis: clinical