Ophthalmic diagnostic imaging using optical coherence tomography (OCT) is limited by bulk eye motions and a
fundamental trade-off between field-of-view (FOV) and sampling density. Here, we introduced a novel multi-volumetric
registration and mosaicking method using our previously described multimodal swept-source spectrally encoded scanning
laser ophthalmoscopy and OCT (SS-SESLO-OCT) system. Our SS-SESLO-OCT acquires an entire en face fundus SESLO
image simultaneously with every OCT cross-section at 200 frames-per-second. In vivo human retinal imaging was
performed in a healthy volunteer, and three volumetric datasets were acquired with the volunteer moving freely and refixating
between each acquisition. In post-processing, SESLO frames were used to estimate en face rotational and
translational motions by registering every frame in all three volumetric datasets to the first frame in the first volume. OCT
cross-sections were contrast-normalized and registered axially and rotationally across all volumes. Rotational and
translational motions calculated from SESLO frames were applied to corresponding OCT B-scans to compensate for interand
intra-B-scan bulk motions, and the three registered volumes were combined into a single interpolated multi-volumetric
mosaic. Using complementary information from SESLO and OCT over serially acquired volumes, we demonstrated multivolumetric
registration and mosaicking to recover regions of missing data resulting from blinks, saccades, and ocular
drifts. We believe our registration method can be directly applied for multi-volumetric motion compensation, averaging,
widefield mosaicking, and vascular mapping with potential applications in ophthalmic clinical diagnostics, handheld
imaging, and intraoperative guidance.
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