![]() The strong optical absorption of hemoglobin within the visible spectral range enabled accurate quantification of total hemoglobin concentration ( 21). In addition to the resolution advantage, vis-OCT offers increased absorption and scattering contrasts in biological tissues, at the cost of reduced penetration depth ( 14, 20). Shorter wavelength can also improve lateral resolution of retinal imaging due to increased numerical aperture (NA), where the incident beam diameter is limited by the eye pupil. A similar resolution can also be attained using an NIR light source centered at 785 nm yet with a FWHM bandwidth of 249 nm, which poses much greater challenges to the optical components and dispersion compensation in the system ( 19). It has been shown that a 1.2-µm axial resolution in air (0.87-µm in tissue) can be achieved using a visible light source centered at 555 nm with a full-width-at-half-maximum (FWHM) spectrum bandwidth of 156 nm, which can reveal tissue structure details at sub-micrometer level ( 14). ![]() Exploiting shorter illumination wavelengths than the majority of OCT systems using near-infrared (NIR) light, vis-OCT offers significantly improved axial resolution using comparable spectral bandwidth ( 15, 18). Visible-light optical coherence tomography (vis-OCT) is a new technical extension of OCT, whose unique capabilities in structural and functional imaging have been demonstrated by several research groups ( 12- 17). Recently, OCT angiography (OCTA) challenged traditional dye-based fluorescence angiography as a non-invasive alternative with additional advantage in 3D imaging and has been applied to investigate almost all major blinding diseases ( 9- 11). Doppler OCT revealed axial blood flow velocity in retinal vessels ( 4- 6), while polarization-sensitive OCT mapped the depolarization properties within multiple retinal layers ( 7, 8). Since its introduction in 1991, a number of technologies were developed to broaden the application of OCT beyond structural imaging. Optical coherence tomography (OCT) revolutionized ophthalmology in both fundamental investigations and clinical care by noninvasively providing high-resolution, three-dimensional (3D), in vivo optical biopsy of the eye ( 1- 3). Keywords: Optical coherence tomography (OCT) high resolution imaging ophthalmology Vis-OCT has the potential to add new anatomical and functional imaging capabilities to ophthalmic clinical care. ![]() Results: The new vis-OCT provided high-quality retinal images of both subjects without any known eye diseases and patients with various retinal diseases, including retinal occlusive disease and diabetic retinopathy (DR) over a broad range of ages.Ĭonclusions: A newly designed vis-OCT system is sufficiently optimized to be suited for routine patients’ examinations in clinics. We acquired raster- and circular-scan images from both healthy and diseased human eyes. ![]() Methods: We developed and optimized a portable vis-OCT system for human retinal imaging in clinical settings. Translating laboratory prototypes to an integrated clinical-environment-friendly system is required to explore the full potential of vis-OCT in disease management. Policy of Dealing with Allegations of Research Misconductīackground: The capabilities of visible-light optical coherence tomography (vis-OCT) in noninvasive anatomical and functional retinal imaging have been demonstrated by multiple groups in both rodents and healthy human subjects.Policy of Screening for Plagiarism Process. ![]()
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