Ultra-Widefield OCT Angiography

Optical Coherence Tomography Angiography (OCTA), a functional extension of OCT, has the potential to replace most invasive fluorescein angiography (FA) exams in ophthalmology. So far, OCTA's field of view is however still lacking behind fluorescence fundus photography techniques. This is problematic, because many retinal diseases manifest at an early stage by changes of the peripheral retinal capillary network. It is therefore desirable to expand OCTA's field of view to match that of ultra-widefield fundus cameras. We present a custom developed clinical high-speed swept-source OCT (SS-OCT) system operating at an acquisition rate 8-16 times faster than today's state-of-the-art commercially available OCTA devices. Its speed allows us to capture ultra-wide fields of view of up to 90 degrees with an unprecedented sampling density and hence extraordinary resolution by merging two single shot scans with 60 degrees in diameter. To further enhance the visual appearance of the angiograms, we developed for the first time a three-dimensional deep learning based algorithm for denoising volumetric OCTA data sets. We showcase its imaging performance and clinical usability by presenting images of patients suffering from diabetic retinopathy.

Automated summary

Optical Coherence Tomography Angiography (OCTA) has the potential to replace invasive fluorescein angiography (FA) in ophthalmology, but it still lacks the field of view compared to fluorescence fundus photography techniques. To address this issue, a custom developed high-speed swept-source OCT (SS-OCT) system is presented, which can capture ultra-wide fields of view up to 90 degrees with high resolution. Additionally, a three-dimensional deep learning based algorithm is developed for denoising volumetric OCTA data sets, enhancing the visual appearance of angiograms.