Project Summary TRD-2 TRD project 2 will develop imaging platforms based on novel circular ranging (CR) architectures of optical coherence tomography. Specific Aim #1 addresses long-standing challenges to using OCT in open surgery. Conventional approaches burdened the surgeon with cumbersome equipment and required disruptions in workflow. We will leverage the depth-independence of CR to enable a head-mounted OCT microscope that can continuously survey the surgical field. This OCT loupe platform will be specifically developed to provide improved visualization of nerves to prevent accidental injury to these delicate and critical tissues, and thereby avoiding some of the most feared surgical morbidities. Specific Aim #2 integrates recent advancements in quantitative flow imaging with extremely rapid retinal CR-OCT technology to enable a platform for wide-field angiography and quantitative flow mapping in the human retina. Quantitative flow imaging will enable comprehensive, pulse resolved maps of the non-capillary retinal vascular networks, positioning investigators to decipher the interaction of retinal perfusion and disease. Wide-field angiography will reduce barriers that have limited clinicians and scientists from reliably and routinely imaging the peripheral retina Through these aims, TRD-2 will develop, validate, and deliver innovative technologies to our collaborating investigators and to the broader biomedical community.