Improving cone identification using merged non-confocal quadrant-detection adaptive optics scanning light ophthalmoscope images.

Cone photoreceptor inner segments visualized in non-confocal split-detection adaptive optics scanning light ophthalmoscope (AOSLO) images appear as obliquely illuminated domes with bright and dark opposing regions. Previously, the pairing of these bright and dark regions for automated photoreceptor identification has necessitated complex algorithms. Here we demonstrate how the merging of split-detection images captured with a non-confocal quadrant light detection scheme allows automated cone identification using simple, open-source image processing tools, while also improving accuracy in both normal and pathologic retinas.

Insights into Sickle Cell Disease through the Retinal Microvasculature: Adaptive Optics Scanning Light Ophthalmoscopy Correlates of Clinical OCT Angiography.

Purpose: Clinical OCT angiography (OCTA) of the retinal microvasculature offers a quantitative correlate to systemic disease burden and treatment efficacy in sickle cell disease (SCD). The purpose of this study was to use the higher resolution of adaptive optics scanning light ophthalmoscopy (AOSLO) to elucidate OCTA features of parafoveal microvascular compromise identified in SCD patients.

Design: Case series of 11 SCD patients and 1 unaffected control.

Efficacy of CRISPR-Based Gene Editing in a Sickle Cell Disease Patient as Measured through the Eye.

Sickle cell disease (SCD) exists on a phenotypic spectrum with variable genetic expressivity, making it difficult to assess an individual patient's risk of complications at any particular point in time. Current and emerging SCD treatments, including CRISPR-based gene editing, result in a variable proportion of affected red blood cells (RBCs) still vulnerable to sickling. Clinical serological indicators of disease such as hemoglobin, indirect bilirubin, and reticulocyte count and clinical metrics including number of emergency department visits and hospitalizations over time often fall short in their ability to objectively quantify ischemic disease activity and efficacy of treatments.

Imaging of vitreous cortex hyalocyte dynamics using non-confocal quadrant-detection adaptive optics scanning light ophthalmoscopy in human subjects.

Vitreous cortex hyalocytes are resident macrophage cells that help maintain the transparency of the media, provide immunosurveillance, and respond to tissue injury and inflammation. In this study, we demonstrate the use of non-confocal quadrant-detection adaptive optics scanning light ophthalmoscopy (AOSLO) to non-invasively visualize the movement and morphological changes of the hyalocyte cell bodies and processes over 1-2 hour periods in the living human eye. The average velocity of the cells 0.

Quantification of intermittent retinal capillary perfusion in sickle cell disease.

Pathophysiology of sickle cell disease (SCD) features intermittent vaso-occlusion of microcirculatory networks that facilitate ischemic damage. Past research has, however, relied on static images to characterize this active disease state. This study develops imaging metrics to more fully capture dynamic vascular changes, quantifying intermittent retinal capillary perfusion in unaffected controls and SCD patients using sequential optical coherence tomography angiography (OCT-A) scans.

Fundus albipunctatus photoreceptor microstructure revealed using adaptive optics scanning light ophthalmoscopy.

Purpose: Fundus albipunctatus is an inherited cause of congenital stationary night blindness. The objective of this report is to describe structural changes occurring in a macular phenotype of a novel RDH5 mutation producing fundus albipunctatus using high-resolution imaging. A 62-year-old male with longstanding night blindness underwent imaging and genetic evaluation.

Functional retinal imaging using adaptive optics swept-source OCT at 1.6 MHz.

Objective optical assessment of photoreceptor function may permit earlier diagnosis of retinal disease than current methods such as perimetry, electrophysiology, and clinical imaging. In this work, we describe an adaptive optics (AO) optical coherence tomography (OCT) system designed to measure functional responses of single cones to visible stimuli. The OCT subsystem consisted of a raster-scanning Fourier-domain mode-locked laser that acquires A scans at 1.

Megahertz-rate optical coherence tomography angiography improves the contrast of the choriocapillaris and choroid in human retinal imaging.

Angiographic imaging of the human eye with optical coherence tomography (OCT) is becoming an increasingly important tool in the scientific investigation and clinical management of several blinding diseases, including age-related macular degeneration and diabetic retinopathy. We have observed that OCT angiography (OCTA) of the human choriocapillaris and choroid with a 1.64 MHz A-scan rate swept-source laser yields higher contrast images as compared to a slower rate system operating at 100 kHz.

Challenges and advantages in wide-field optical coherence tomography angiography imaging of the human retinal and choroidal vasculature at 1.7-MHz A-scan rate.

We present noninvasive, three-dimensional, depth-resolved imaging of human retinal and choroidal blood circulation with a swept-source optical coherence tomography (OCT) system at 1065-nm center wavelength. Motion contrast OCT imaging was performed with the phase-variance OCT angiography method. A Fourier-domain mode-locked light source was used to enable an imaging rate of 1.

The Properties of Outer Retinal Band Three Investigated With Adaptive-Optics Optical Coherence Tomography.

Purpose: Optical coherence tomography's (OCT) third outer retinal band has been attributed to the zone of interdigitation between RPE cells and cone outer segments. The purpose of this paper is to investigate the structure of this band with adaptive optics (AO)-OCT.

Methods: Using AO-OCT, images were obtained from two subjects.

Comparison of amplitude-decorrelation, speckle-variance and phase-variance OCT angiography methods for imaging the human retina and choroid.

We compared the performance of three OCT angiography (OCTA) methods: speckle variance, amplitude decorrelation and phase variance for imaging of the human retina and choroid. Two averaging methods, split spectrum and volume averaging, were compared to assess the quality of the OCTA vascular images. All data were acquired using a swept-source OCT system at 1040 nm central wavelength, operating at 100,000 A-scans/s.

Crosstalk rejection in parallel optical coherence tomography using spatially incoherent illumination with partially coherent sources.

The continuing improvement of high-speed area-scan cameras has made possible the construction of parallel optical coherence tomography (OCT) systems that are competitive with the fastest demonstrated swept-source OCT systems. Unfortunately, when imaging through turbid media using a partially coherent source, parallel OCT suffers resolution loss from coherent multiple scattering, a phenomenon known as crosstalk. We demonstrate the use of a full-field OCT system employing multimode fiber in the illumination arm to reduce the spatial coherence of a partially coherent source.