Purpose
To design a visualization system, which displays solid-mesh segmentation reconstructions with reflection intensity based texturing of optical coherence tomography (OCT) data sets in an interactive head mounted virtual reality display.
Methods
OCT data sets of 4 patients with vitreo-macular traction was collected before, one week after, 4 weeks after, 3 months after, 6 months after, and one year after intravitreal injections of Ocriplasmin. The OCT data sets were imported into MAXON Cinema 4D™ where they were segmented into a triangle mesh based on the OCT threshold intensities using custom built algorithms. The resulting meshes were given UV texture coordinates and a vertex map relating to the nearest reflection intensity was applied. These textured meshes were then exported to UNITY 3D™ and visualized using an Oculus Rift™ virtual reality head set.
Results
6 data sets were collected from 4 patients resulting in 24 collected and converted data sets. Visualizations of each data set achieved a crisp and clear display of the pathology changing over time. The end-user was able to freely move around in the data set using a joystick. Any movement of the end-user's head was immediately translated into corresponding changes of the virtual cameras direction, angle, and pitch, allowing the end-user to freely explore and look around inside the pathology. With the click of a button the end-user was able to scroll through the data sets temporally, making it possible to visualize not only the three dimensional structures of the pathology, but also its changes over time in reaction to the surgical intervention.
Conclusions
The achieved interactivity and visualization quality of the virtual reality head set was very high. The primary drawback of this generation of displays is the pixel resolution, which is still slightly too low, making single pixels still discernable and causing slight ghosting. This problem will be addressed in the next iteration. This technology promises to aid clinical understanding of vitreo-retinal pathologies both in educational and research settings.