Retinal racemose hemangioma presenting with a chorioretinal anastomosis.

Purpose: To report a case of neovascular glaucoma in an 8-year-old male, secondary to a racemose hemangioma without associated intracranial arteriovenous malformation, highlighting the challenges in management and novel findings on optical coherence tomography angiography (OCTA).

Observations: An 8-year-old male initially presented with pain, redness, and blurred vision in the right eye. The patient was diagnosed with secondary neovascular glaucoma due to a racemose hemangioma.

Delayed orbital floor implant complications: Case report and review of the literature.

Purpose: Foreign body reaction to non-absorbable alloplastic orbital implants utilized for bony reconstruction are infrequently documented in the literature. We present the workup and surgical management of a giant cystic mass encapsulating a patient's alloplastic orbital implant, which was ultimately deemed to be a result of foreign body reaction.

Observations: A 41-year-old male patient with distant history of a right orbital floor fracture had undergone repair with the placement of a nylon foil implant.

Perivenular Capillary Loss: An Early, Quantifiable Change in Macular Telangiectasia Type 2.

Purpose: To evaluate differences in parafoveal vascular density surrounding arterioles and venules in type 2 macular telangiectasia (MacTel).

Methods: Thirty-seven eyes (20 subjects) diagnosed with MacTel and 16 healthy eyes (10 subjects) were imaged with optical coherence tomography angiography between March 2016 and June 2019 in this single-center, observational, cross-sectional study. Arterioles and venules were manually identified, and perivascular density was generated using a custom MATLAB code.

RainbowSTORM: an open-source ImageJ plug-in for spectroscopic single-molecule localization microscopy (sSMLM) data analysis and image reconstruction.

Summary: Spectroscopic single-molecule localization microscopy (sSMLM) simultaneously captures the spatial locations and full spectra of stochastically emitting fluorescent single molecules. It provides an optical platform to develop new multimolecular and functional imaging capabilities. While several open-source software suites provide subdiffraction localization of fluorescent molecules, software suites for spectroscopic analysis of sSMLM data remain unavailable.

Spectrally dependent roll-off in visible-light optical coherence tomography.

Recent development of visible-light optical coherence tomography (vis-OCT) has introduced new applications for noninvasive spectroscopic imaging. However, the measured spectra may be altered by spectrally dependent roll-off (SDR). We formulated a mathematical model for SDR that accounted for nonuniform wavenumber spacing, optical aberrations, and misalignments in the spectrometer.

Drusen diagnosis comparison between hyper-spectral and color retinal images.

Age-related macular degeneration (AMD) is a degenerative aging disorder, which can lead to irreversible vision loss in older individuals. The emergence of clinical applications of retinal hyper-spectral imaging provides a unique opportunity to capture important spectral signatures, with the potential to enhance the molecular diagnosis of retinal diseases. In this study, we use a machine learning classification approach to explore whether hyper-spectral images offer an improved outcome compared to standard RGB images.

Visible-light optical coherence tomography oximetry based on circumpapillary scan and graph-search segmentation.

Visible-light optical coherence tomography (vis-OCT) enables retinal oximetry by measuring the oxygen saturation of hemoglobin (sO) from within individual retinal blood vessels. The sO calculation requires reliable estimation of the true spectrum of backscattered light from the posterior vessel wall. Unfortunately, subject motion and image noise make averaging from multiple A-lines at the same depth position challenging, and lead to inaccurate sO estimation.

The Correlation of Pars Plana Incision and Transient Hypotony After Silicone Oil Removal.

Background And Objective: To evaluate the correlation between pars plana incision and transient hypotony after silicone oil removal in aphakic eyes PATIENTS AND METHODS:Twenty-two patients with aphakia and a high degree of myopia with silicone oil tamponade were recruited for this prospective study and randomly scheduled to two groups for silicone oil removal: 3.5-mm corneal incision with suture corneal or 20-gauge pars plana incision with suture. Intraocular pressure (IOP) was measured and fundus and anterior structure were examined preoperatively on the first, third, and seventh postoperative day and at 1 month after surgery.

Projection-Resolved OCT Angiography of Microvascular Changes in Paracentral Acute Middle Maculopathy and Acute Macular Neuroretinopathy.

Purpose: To identify the microvascular changes associated with paracentral acute middle maculopathy (PAMM) and acute macular neuroretinopathy (AMN) and to improve our understanding of the relevant involvement of the three retinal capillary plexuses using projection-resolved optical coherence tomography angiography (PR-OCTA).

Methods: This was a retrospective study of 18 eyes with AMN or PAMM imaged with OCTA. We used cross-sectional PR-OCTA to localize reduced flow signal to the superficial (SCP), middle (MCP), or deep capillary plexus (DCP) or choriocapillaris that corresponded to inner retinal PAMM or outer retinal AMN lesions on OCT.

Volume-Rendered Projection-Resolved OCT Angiography: 3D Lesion Complexity Is Associated With Therapy Response in Wet Age-Related Macular Degeneration.

Purpose: To explore whether quantitative three-dimensional (3D) analysis of choroidal neovascularization (CNV) using projection-resolved optical coherence tomography angiography (PR-OCTA) is associated with treatment response in neovascular age-related macular degeneration (nAMD).

Methods: Retrospective, cross-sectional study of 51 eyes of 49 patients undergoing individualized anti-VEGF therapy for nAMD. Patients were classified as "good" or "poor" responders, requiring injections at less or more frequently than 6-week intervals, respectively.

MULTILEVEL ISCHEMIA IN DISORGANIZATION OF THE RETINAL INNER LAYERS ON PROJECTION-RESOLVED OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

Purpose: To examine the relationship between ischemia and disorganization of the retinal inner layers (DRIL).

Methods: Cross-sectional retrospective study of 20 patients (22 eyes) with diabetic retinopathy presenting to a tertiary academic referral center, who had DRIL on structural optical coherence tomography (OCT) using Spectralis HRA + OCT (Heidelberg Engineering, Heidelberg, Germany) and OCT angiography with XR Avanti (Optovue Inc, Fremont, CA) on the same day. Optical coherence tomography angiography images were further processed to remove flow signal projection artifacts using a software algorithm adapted from recent studies.

Optical coherence tomography angiography of retinal vascular occlusions produced by imaging-guided laser photocoagulation.

Retinal vascular occlusive diseases represent a major form of vision loss worldwide. Rodent models of these diseases have traditionally relied upon a slit-lamp biomicroscope to help visualize the fundus and subsequently aid delivery of high-power laser shots to a target vessel. Here we describe a multimodal imaging system that can produce, image, and monitor retinal vascular occlusions in rodents.

OCT angiography and visible-light OCT in diabetic retinopathy.

In recent years, advances in optical coherence tomography (OCT) techniques have increased our understanding of diabetic retinopathy, an important microvascular complication of diabetes. OCT angiography is a non-invasive method that visualizes the retinal vasculature by detecting motion contrast from flowing blood. Visible-light OCT shows promise as a novel technique for quantifying retinal hypoxia by measuring the retinal oxygen delivery and metabolic rates.

Monitoring Acute Stroke in Mouse Model Using Laser Speckle Imaging-Guided Visible-Light Optical Coherence Tomography.

Objective: Monitoring hemodynamic and vascular changes in the acute stages of mouse stroke models is invaluable in studying ischemic stroke pathophysiology. However, there lacks a tool to simultaneously and dynamically investigate these changes.

Methods: We integrated laser speckle imaging (LSI) and visible-light optical coherence tomography (Vis-OCT) to reveal dynamic vascular responses in acute stages in the distal middle cerebral artery occlusion (dMCAO) model in rodents.

Increased Retinal Oxygen Metabolism Precedes Microvascular Alterations in Type 1 Diabetic Mice.

Purpose: To investigate inner retinal oxygen metabolic rate (IRMRO2) during early stages of type 1 diabetes in a transgenic mouse model.

Methods: In current study, we involved seven diabetic mice (Akita/+, TSP1-/-) and seven control mice (TSP1-/-), and applied visible-light optical coherence tomography (vis-OCT) to image functional parameters including retinal blood flow rate, oxygen saturation (sO2) and the IRMRO2 value longitudinally from 5 weeks of age to 13 weeks of age. After imaging at 13 weeks of age, we analyzed the imaging results, and examined histology of mouse retina.

Stochastic fluorescence switching of nucleic acids under visible light illumination.

We report detailed characterizations of stochastic fluorescence switching of unmodified nucleic acids under visible light illumination. Although the fluorescent emission from nucleic acids under the visible light illumination has long been overlooked due to their apparent low absorption cross section, our quantitative characterizations reveal the high quantum yield and high photon count in individual fluorescence emission events of nucleic acids at physiological concentrations. Owing to these characteristics, the stochastic fluorescence switching of nucleic acids could be comparable to that of some of the most potent exogenous fluorescence probes for localization-based super-resolution imaging.

Choriocapillaris Nonperfusion is Associated With Poor Visual Acuity in Eyes With Reticular Pseudodrusen.

Purpose: To study choriocapillaris blood flow in age-related macular degeneration (AMD) using optical coherence tomography angiography (OCTA) and study its correlation to visual acuity (VA) in eyes with reticular pseudodrusen (RPD) vs those with drusen without RPD (drusen).

Design: Cross-sectional study.

Methods: Patients with either drusen or RPD in early AMD underwent OCTA imaging of the superior, inferior, and/or nasal macula.

CHARACTERIZATION OF THE MIDDLE CAPILLARY PLEXUS USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN HEALTHY AND DIABETIC EYES.

Purpose: To assess the ability of optical coherence tomography angiography to image the retinal middle capillary plexus (MCP), and to characterize the MCP as a unique vascular network separate from the superficial and deep capillary plexus (DCP).

Methods: Healthy and diabetic eyes were imaged using the Avanti XR optical coherence tomography angiography instrument (Optovue Inc, Fremont, CA). Using manual segmentation of the retinal layers, the authors generated en face angiograms to distinguish the three capillary plexuses (superficial capillary plexus, MCP, DCP).

Imaging hemodynamic response after ischemic stroke in mouse cortex using visible-light optical coherence tomography.

Visible-light optical coherence tomography (Vis-OCT) is an emerging technology that can image hemodynamic response in microvasculature. Vis-OCT can retrieve blood oxygen saturation (sO) mapping using intrinsic optical absorption contrast while providing high-resolution anatomical vascular structures at the same time. To improve the accuracy of Vis-OCT oximetry on vessels embedded in highly scattering medium, i.

Visible-Light Optical Coherence Tomography Angiography for Monitoring Laser-Induced Choroidal Neovascularization in Mice.

Purpose: This study sought to determine the earliest time-point at which evidence of choroidal neovascularization (CNV) could be detected with visible-light optical coherence tomography angiography (vis-OCTA) in a mouse model of laser-induced CNV.

Methods: Visible light-OCTA was used to study laser-induced CNV at different time-points after laser injury to monitor CNV development and measure CNV lesion size. Measurements obtained from vis-OCTA angiograms were compared with histopathologic measurements from isolectin-stained choroidal flatmounts.

A Mouse Model for Laser-induced Choroidal Neovascularization.

The mouse laser-induced choroidal neovascularization (CNV) model has been a crucial mainstay model for neovascular age-related macular degeneration (AMD) research. By administering targeted laser injury to the RPE and Bruch's membrane, the procedure induces angiogenesis, modeling the hallmark pathology observed in neovascular AMD. First developed in non-human primates, the laser-induced CNV model has come to be implemented into many other species, the most recent of which being the mouse.

Inner retinal oxygen metabolism in the 50/10 oxygen-induced retinopathy model.

Retinopathy of prematurity (ROP) represents a major cause of childhood vision loss worldwide. The 50/10 oxygen-induced retinopathy (OIR) model mimics the findings of ROP, including peripheral vascular attenuation and neovascularization. The oxygen metabolism of the inner retina has not been previously explored in this model.

Simultaneous photoacoustic microscopy of microvascular anatomy, oxygen saturation, and blood flow.

Capitalizing on the optical absorption of hemoglobin, photoacoustic microscopy (PAM) is uniquely capable of anatomical and functional characterization of the intact microcirculation in vivo. However, PAM of the metabolic rate of oxygen (MRO) at the microscopic level remains an unmet challenge, mainly due to the inability to simultaneously quantify microvascular diameter, oxygen saturation of hemoglobin (sO), and blood flow at the same spatial scale. To fill this technical gap, we have developed a multi-parametric PAM platform.

Microvascular quantification based on contour-scanning photoacoustic microscopy.

Accurate quantification of microvasculature remains of interest in fundamental pathophysiological studies and clinical trials. Current photoacoustic microscopy can noninvasively quantify properties of the microvasculature, including vessel density and diameter, with a high spatial resolution. However, the depth range of focus (i.