Proceedings Article | 17 February 2017
KEYWORDS: Optical coherence tomography, Scanning laser ophthalmoscopy, Imaging systems, Multimodal imaging, Ophthalmic imaging, In vivo imaging, Retinal scanning, Optical scanning systems, Eye, Optical tracking, Image segmentation, Scanners, Relays, Signal to noise ratio
Multimodal imaging systems that combine scanning laser ophthalmoscopy (SLO) and optical coherence tomography
(OCT) have demonstrated the utility of concurrent en face and volumetric imaging for aiming, eye tracking, bulk motion
compensation, mosaicking, and contrast enhancement. However, this additional functionality trades off with increased
system complexity and cost because both SLO and OCT generally require dedicated light sources, galvanometer scanners,
relay and imaging optics, detectors, and control and digitization electronics. We previously demonstrated multimodal
ophthalmic imaging using swept-source spectrally encoded SLO and OCT (SS-SESLO-OCT). Here, we present system
enhancements and a new optical design that increase our SS-SESLO-OCT data throughput by >7x and field-of-view (FOV)
by >4x. A 200 kHz 1060 nm Axsun swept-source was optically buffered to 400 kHz sweep-rate, and SESLO and OCT
were simultaneously digitized on dual input channels of a 4 GS/s digitizer at 1.2 GS/s per channel using a custom k-clock.
We show in vivo human imaging of the anterior segment out to the limbus and retinal fundus over a >40° FOV. In addition,
nine overlapping volumetric SS-SESLO-OCT volumes were acquired under video-rate SESLO preview and guidance. In
post-processing, all nine SESLO images and en face projections of the corresponding OCT volumes were mosaicked to
show widefield multimodal fundus imaging with a >80° FOV. Concurrent multimodal SS-SESLO-OCT may have
applications in clinical diagnostic imaging by enabling aiming, image registration, and multi-field mosaicking and benefit
intraoperative imaging by allowing for real-time surgical feedback, instrument tracking, and overlays of computationally
extracted image-based surrogate biomarkers of disease.
