Peripheral Exudative Hemorrhagic Chorioretinopathy (PEHCR): Diagnostic and Therapeutic Challenges.

Background and Objectives: Peripheral exudative hemorrhagic chorioretinopathy (PEHCR) is a peripheral retinal vascular abnormality that is likely underreported. We review the differential diagnoses, etiology, and treatment options for PEHCR. Methods: We present a case of an asymptomatic 72-year-old female referred following left eye fundus photography finding of the peripheral lesion. Results: Fundus photography demonstrated a large temporal pigment epithelial detachment (PED) with adjacent fibrovascular membrane. Optical coherence tomography (OCT) confirmed the PED with trace subretinal fluid. Fluorescein angiography (FA) demonstrated early and late hypofluorescence of the PED with late leakage of the adjacent temporal fibrovascular membrane. Observation was elected, visual acuity remained unaffected, and the PED spontaneously resolved. Conclusions: Due to the peripheral location, patients often present as asymptomatic; however, vision loss can occur due to vitreous hemorrhage or extension of subretinal fluid, hemorrhage, or exudate to the macula. Commonly, these lesions are referred with concern for choroidal melanoma due to their large, dark, elevated presentation in the peripheral retina. Multimodal testing using B-scan, FA, and OCT is important in establishing the proper diagnosis. PEHCR lesions can often be observed without treatment, though intravitreal injection of anti-VEGF is increasingly used to prevent secondary causes of vision loss.

CD40 Signaling in Mice Elicits a Broad Antiviral Response Early during Acute Infection with RNA Viruses.

Macrophages are critical in the pathogenesis of a diverse group of viral pathogens, both as targets of infection and for eliciting primary defense mechanisms. Our prior in vitro work identified that CD40 signaling in murine peritoneal macrophages protects against several RNA viruses by eliciting IL-12, which stimulates the production of interferon gamma (IFN-γ). Here, we examine the role of CD40 signaling in vivo. We show that CD40 signaling is a critical, but currently poorly appreciated, component of the innate immune response using two distinct infectious agents: mouse-adapted influenza A virus (IAV, PR8) and recombinant VSV encoding the Ebola virus glycoprotein (rVSV-EBOV GP). We find that stimulation of CD40 signaling decreases early IAV titers, whereas loss of CD40 elevated early titers and compromised lung function by day 3 of infection. Protection conferred by CD40 signaling against IAV is dependent on IFN-γ production, consistent with our in vitro studies. Using rVSV-EBOV GP that serves as a low-biocontainment model of filovirus infection, we demonstrate that macrophages are a CD40-expressing population critical for protection within the peritoneum and T-cells are the key source of CD40L (CD154). These experiments reveal the in vivo mechanisms by which CD40 signaling in macrophages regulates the early host responses to RNA virus infection and highlight how CD40 agonists currently under investigation for clinical use may function as a novel class of broad antiviral treatments.

NONSURGICAL RESOLUTION OF FULL-THICKNESS MACULAR HOLES WITHOUT VITREOMACULAR TRACTION.

BACKGROUND/PURPOSE: The purpose of this study was to report a case series of full-thickness macular holes without vitreomacular traction that resolved without surgery. METHODS: This study is a retrospective case series of 11 patients who demonstrated closure of full-thickness macular holes without surgical intervention. RESULTS: All full-thickness macular holes closed, with all patients having improvement in visual acuity. All but one of the cases had visual acuity better than 20/40 at last recorded visit. Most cases presented with associated epiretinal membrane (73%), cystoid changes (64%), defects <150 µ m (80%), and resolved within 2 months (91%). Topical anti-inflammatory drops were used in 7 of 11 cases, and dorzolamide was used in one case. CONCLUSION: Full-thickness macular holes can develop in eyes without the presence of vitreomacular traction. Topical therapy without vitrectomy may be particularly helpful in closure of full-thickness macular holes with associated cystoid macular edema. Holes with a lamellar hole component may spontaneously resolve as part of a retinal remodeling process.

Complications of Intra-Arterial tPA for Iatrogenic Branch Retinal Artery Occlusion: A Case Report through Multimodal Imaging and Literature Review.

Background and Objectives: To document, through multimodal imaging, the post-procedural clinical course and visual outcome of a patient who received intra-arterial tissue plasminogen activator (tPA) for acute iatrogenic branch retinal artery occlusion (BRAO), and to review the literature and guidelines regarding the use of tPA for retinal arterial occlusions. Methods: A 28-year-old female patient who sustained an iatrogenic BRAO and subsequently received intra-arterial tPA was followed through her post-interventional course of 3 months with serial exams and multimodal imaging, including color fundus photography, visual field testing, spectral domain optical coherence tomography (SD-OCT), and OCT angiography (OCT-A). Results: A patient with history of left internal cerebral artery (ICA) aneurysm and baseline visual acuity (VA) of 20/20 developed an acutely symptomatic BRAO after undergoing a neuroendovascular procedure and was acutely treated with tPA through the left ophthalmic artery. At two weeks follow-up, a central posterior pole hemorrhage was noted although VA was preserved. A superior altitudinal defect was shown on automated perimetry. VA dropped to 20/50 at 7 weeks follow-up and hyperreflective material deep to the attachment between the posterior hyaloid and the internal limiting membrane (ILM) consistent with hemorrhage was noted on SD-OCT. At 11 weeks follow-up, VA returned to 20/20, SD-OCT revealed a membrane bridging the foveal depression, OCT-A showed decreased vascularity in the inferior macula, and the visual field defect was stable by automated perimetry. Conclusions: Intraocular hemorrhage is a possible complication of intra-arterial tPA administration for BRAO, and a careful analysis of risks, benefits, and goals of this procedure must be considered by both provider and patient before such intervention.

Uveitis reactivation following recombinant zoster vaccination.

PURPOSE: Describe three cases of uveitis reactivation following immunization with recombinant zoster vaccine (RZV). OBSERVATIONS: One patient developed reactivation of previously controlled multifocal choroiditis within one week of receiving RZV, requiring treatment with systemic corticosteroids. Two patients with previously controlled anterior uveitis developed new anterior segment inflammation after RZV; both were treated with topical corticosteroids and systemic antiviral therapy. CONCLUSION AND IMPORTANCE: Uveitis recurrence is an infrequent but serious potential ocular side effect of recombinant zoster vaccination.

Frequency of Urgent or Emergent Vitreoretinal Surgical Procedures in the United States During the COVID-19 Pandemic.

Importance: The American Academy of Ophthalmology (AAO) indicated that urgent or emergent vitreoretinal surgical procedures should continue during the coronavirus disease 2019 (COVID-19) pandemic. Although decreases in the frequency of critical procedures have been reported outside the field of ophthalmology, analyses are limited by volume, geography, and time. Objective: To evaluate whether the frequency of ophthalmic surgical procedures deemed urgent or emergent by the AAO changed across the United States during the COVID-19 pandemic. Design, Setting, and Participants: Vitreoretinal practices from 17 institutions throughout the US participated in this multicenter cross-sectional study. The frequency of 11 billed vitreoretinal Current Procedural Terminology (CPT) codes across respective weeks was obtained from each practice between January 1, 2019, and May 31, 2020. Data were clustered into intravitreal injections (code 67028), lasers and cryotherapy (codes 67141, 67145, and 67228), retinal detachment (RD) repairs (codes 67107, 67108, 67110, and 67113), and other vitrectomies (codes 67036, 67039, and 67040). Institutions were categorized by region (Northeast, Midwest, South, and West Coast), practice setting (academic [tax-exempt] or private [non-tax-exempt]), and date of respective statewide stay-at-home orders. Main Outcomes and Measures: Nationwide changes in the frequency of billing for urgent or emergent vitreoretinal surgical procedures during the COVID-19 pandemic. Results: A total of 526 536 CPT codes were ascertained: 483 313 injections, 19 257 lasers or cryotherapy, 14 949 RD repairs, and 9017 other vitrectomies. Relative to 2019, a weekly institutional decrease in injections was observed from March 30 to May 2, 2020, with a maximal 38.6% decrease (from a mean [SD] of 437.8 [436.3] to 273.8 [269.0] injections) from April 6 to 12, 2020 (95% CI, -259 to -69 injections; P = .002). A weekly decrease was also identified that spanned a longer interval, at least until study conclusion (March 16 to May 31, 2020), for lasers and cryotherapy, with a maximal 79.6% decrease (from a mean [SD] of 6.6 [7.7] to 1.5 [2.0] procedures) from April 6 to 12, 2020 (95% CI, -6.8 to -3.3 procedures; P < .001), for RD repairs, with a maximal 59.4% decrease (from a mean [SD] of 3.5 [4.0] to 1.6 [2.2] repairs) from April 13 to 19, 2020 (95% CI, -2.7 to -1.4 repairs; P < .001), and for other vitrectomies, with a maximal 84.3% decrease (from a mean [SD] of 3.0 [3.1] to 0.4 [0.8] other vitrectomies) from April 6 to 12, 2020 (95% CI, -3.3 to -1.8 other vitrectomies; P < .001). No differences were identified by region, setting, or state-level stay-at-home order adjustment. Conclusions and Relevance: Although the AAO endorsed the continued performance of urgent or emergent vitreoretinal surgical procedures, the frequency of such procedures throughout the country experienced a substantial decrease that may persist after the COVID-19 pandemic's initial exponential growth phase. This decrease appears independent of region, setting, and state-level stay-at-home orders. It is unknown to what extent vitreoretinal intervention would have decreased without AAO recommendations, and how the decrease is associated with outcomes. Although safety is paramount during the COVID-19 pandemic, practices should consider prioritizing availability for managing high-acuity conditions until underlying reasons for the reduction are fully appreciated.

Interaction between nectin-1 and the human natural killer cell receptor CD96.

Regulation of Natural Killer (NK) cell activity is achieved by the integration of both activating and inhibitory signals acquired at the immunological synapse with potential target cells. NK cells express paired receptors from the immunoglobulin family which share common ligands from the nectin family of adhesion molecules. The activating receptor CD226 (DNAM-1) binds to nectin-2 and CD155, which are also recognized by the inhibitory receptor TIGIT. The third receptor in this family is CD96, which is less well characterized and may have different functions in human and mouse models. Human CD96 interacts with CD155 and ligation of this receptor activates NK cells, while in mice the presence of CD96 correlates with decreased NK cell activation. Mouse CD96 also binds nectin-1, but the effect of this interaction has not yet been determined. Here we show that human nectin-1 directly interacts with CD96 in vitro. The binding site for CD96 is located on the nectin-1 V-domain, which comprises a canonical interface that is shared by nectins to promote cell adhesion. The affinity of nectin-1 for CD96 is lower than for other nectins such as nectin-3 and nectin-1 itself. However, the affinity of nectin-1 for CD96 is similar to its affinity for herpes simplex virus glycoprotein D (HSV gD), which binds the nectin-1 V-domain during virus entry. The affinity of human CD96 for nectin-1 is lower than for its known activating ligand CD155. We also found that human erythroleukemia K562 cells, which are commonly used as susceptible targets to assess NK cell cytotoxicity did not express nectin-1 on their surface and were resistant to HSV infection. When expressed in K562 cells, nectin-1-GFP accumulated at cell contacts and allowed HSV entry. Furthermore, overexpression of nectin-1-GFP led to an increased susceptibility of K562 cells to NK-92 cell cytotoxicity.

Naturally Produced Defensive Alkenal Compounds Activate TRPA1.

(E)-2-alkenals are aldehydes containing an unsaturated bond between the alpha and beta carbons. 2-alkenals are produced by many organisms for defense against predators and secretions containing (E)-2-alkenals cause predators to stop attacking and allow the prey to escape. Chemical ecologists have described many alkenal compounds with 3-20 carbons common, having varied positions of double bonds and substitutions. How do these defensive alkenals act to deter predators? We have tested the effects of (E)-2-alkenals with 6-12 carbons on transient receptor potential channels (TRP) commonly found in sensory neurons. We find that (E)-2-alkenals activate transient receptor potential ankyrin subtype 1 (TRPA1) at low concentrations-EC50s 10-100 µM (in 0 added Ca(2+) external solutions). Other TRP channels were either weakly activated (TRPV1, TRPV3) or insensitive (TRPV2, TRPV4, TRPM8). (E)-2-alkenals may activate TRPA1 by modifying cysteine side chains. However, target cysteines include others beyond the 3 in the amino-terminus implicated in activation, as a channel with cysteines at 621, 641, 665 mutated to serine responded robustly. Related chemicals, including the aldehydes hexanal and decanal, and (E)-2-hexen-1-ol also activated TRPA1, but with weaker potency. Rat trigeminal nerve recordings and behavioral experiments showed (E)-2-hexenal was aversive. Our results suggest that TRPA1 is likely a major target of these commonly used defensive chemicals.