Robotic optical coherence tomography with expanded three-dimensional field-of-view using point-cloud-based volumetric montaging

Imaging complex, non-planar anatomies with optical coherence tomography (OCT) is limited by the optical field of view (FOV) in a single volumetric acquisition. Combining linear mechanical translation with OCT extends the FOV but suffers from inflexibility in imaging non-planar anatomies. We report the robotic OCT to fill this gap. To address challenges in volumetric reconstruction associated with the robotic movement accuracy being two orders of magnitudes worse than OCT imaging resolution, we developed a volumetric montaging algorithm. To test the robotic OCT, we imaged the entire circumferential aqueous humor outflow pathway, whose imaging has the potential to customize glaucoma surgeries but is typically constrained by the FOV in mice in vivo. We acquired volumetric OCT data at different robotic poses and reconstructed the entire anterior segment of the eye. From the segmented Schlemm’s canal volume, we showed its circumferentially heterogeneous morphology; we also revealed a segmental nature in the circumferential distribution of collector channels with spatial features as small as a few micrometers.