Barrett AM, Houston KE. Update on the Clinical Approach to Spatial Neglect. Curr Neurol Neurosci Rep 2019;19(5):25.Abstract
PURPOSE OF REVIEW: Spatial neglect is asymmetric orienting and action after a brain lesion, causing functional disability. It is common after a stroke; however, it is vastly underdocumented and undertreated. This article addresses the implementation gap in identifying and treating spatial neglect, to reduce disability and improve healthcare costs and burden. RECENT FINDINGS: Professional organizations published recommendations to implement spatial neglect care. Physicians can lead an interdisciplinary team: functionally relevant spatial neglect assessment, evidence-based spatial retraining, and integrated spatial and vision interventions can optimize outcomes. Research also strongly suggests spatial neglect adversely affects motor systems. Spatial neglect therapy might thus "kick-start" rehabilitation and improve paralysis recovery. Clinicians can implement new techniques to detect spatial neglect and lead interdisciplinary teams to promote better, integrated spatial neglect care. Future studies of brain imaging biomarkers to detect spatial neglect, and real-world applicability of prism adaptation treatment, are needed.
Yazdani M, Chen X, Tashbayev B, Utheim ØA, Ræder S, Hua Y, Eidet JR, Stojanovic A, Dartt DA, Utheim TP. Evaluation of the Ocular Surface Disease Index Questionnaire as a Discriminative Test for Clinical Findings in Dry Eye Disease Patients. Curr Eye Res 2019;44(9):941-947.Abstract
: To investigate to what extent the OSDI can be utilized as a discriminative test for clinical findings. : One thousand and ninety patients with dry eye disease (DED) were consecutively included and examined for osmolarity, tear film break-up time (TFBUT), ocular protection index (OPI), ocular surface staining (OSS), Schirmer I test (ST), meibum expressibility (ME), meibum quality (MQ), and diagnosis of meibomian gland dysfunction (MGD). Receiver-operating characteristic curve (ROC) analysis considering optimum balanced sensitivity and specificity (close to 50%) was used for assessment. : The present study on more than 1,000 patients indicates that the OSDI in the ROC curve analysis is a poor discriminator of pathological scores for TFBUT ≤ 5 (AUC = 0.553; = .012) and ≤10 s (AUC = 0.608; = .002), OSS ≥ 3 (AUC = 0.54; = .043), ST ≤ 5 (AUC = 0.550; = .032) and ≤10 mm/5 min (AUC = 0.544; = .016), and ME ≥ 1 (AUC = 0.594; = <0.001). Pathological scores for osmolarity >308 and >316 mOsm/L, OPI, OSS > 1, MQ, and MGD could not be discriminated by OSDI ( > .05). : Cut-off values for the OSDI can be defined to discriminate pathological TFBUT (≤5 and ≤10), OSS (≥3), ST (≤5 and ≤10) and ME, however, the discriminability was low. Our comprehensive study emphasises the importance of taking both symptoms and signs into account in DED management.
Wan A, Place E, Pierce EA, Comander J. Characterizing variants of unknown significance in rhodopsin: A functional genomics approach. Hum Mutat 2019;40(8):1127-1144.Abstract
Characterizing the pathogenicity of DNA sequence variants of unknown significance (VUS) is a major bottleneck in human genetics, and is increasingly important in determining which patients with inherited retinal diseases could benefit from gene therapy. A library of 210 rhodopsin (RHO) variants from literature and in-house genetic diagnostic testing were created to efficiently detect pathogenic RHO variants that fail to express on the cell surface. This study, while focused on RHO, demonstrates a streamlined, generalizable method for detecting pathogenic VUS. A relatively simple next-generation sequencing-based readout was developed so that a flow cytometry-based assay could be performed simultaneously on all variants in a pooled format, without the need for barcodes or viral transduction. The resulting dataset characterized the surface expression of every RHO library variant with a high degree of reproducibility (r  = 0.92-0.95), recategorizing 37 variants. For example, three retinitis pigmentosa pedigrees were solved by identifying VUS which showed low expression levels (p.G18D, p.G101V, and p.P180T). Results were validated across multiple assays and correlated with clinical disease severity. This study presents a parallelized, higher-throughput cell-based assay for the functional characterization of VUS in RHO, and can be applied more broadly to other inherited retinal disease genes and other disorders.
Nocera AL, Mueller SK, Stephan JR, Hing L, Seifert P, Han X, Lin DT, Amiji MM, Libermann T, Bleier BS. Exosome swarms eliminate airway pathogens and provide passive epithelial immunoprotection through nitric oxide. J Allergy Clin Immunol 2019;143(4):1525-1535.e1.Abstract
BACKGROUND: Nasal mucosa-derived exosomes (NMDEs) harbor immunodefensive proteins and are capable of rapid interepithelial protein transfer. OBJECTIVES: We sought to determine whether mucosal exposure to inhaled pathogens stimulates a defensive swarm of microbiocidal exosomes, which also donate their antimicrobial cargo to adjacent epithelial cells. METHODS: We performed an institutional review board-approved study of healthy NMDE secretion after Toll-like receptor (TLR) 4 stimulation by LPS (12.5 μg/mL) in the presence of TLR4 inhibitors. Interepithelial transfer of exosomal nitric oxide (NO) synthase and nitric oxide was measured by using ELISAs and NO activity assays. Exosomal antimicrobial assays were performed with Pseudomonas aeruginosa. Proteomic analyses were performed by using SOMAscan. RESULTS: In vivo and in vitro LPS exposure induced a 2-fold increase in NMDE secretion along with a 2-fold increase in exosomal inducible nitric oxide synthase expression and function through TLR4 and inhibitor of nuclear factor κB kinase activation. LPS stimulation increased exosomal microbiocidal activity against P aeruginosa by almost 2 orders of magnitude. LPS-stimulated exosomes induced a 4-fold increase in NO production within autologous epithelial cells with protein transfer within 5 minutes of contact. Pathway analysis of the NMDE proteome revealed 44 additional proteins associated with NO signaling and innate immune function. CONCLUSIONS: We provide direct in vivo evidence for a novel exosome-mediated innate immunosurveillance and defense mechanism of the human upper airway. These findings have implications for lower airway innate immunity, delivery of airway therapeutics, and host microbiome regulation.
Khateb S, Nassisi M, Bujakowska KM, Méjécase C, Condroyer C, Antonio A, Foussard M, Démontant V, Mohand-Saïd S, Sahel J-A, Zeitz C, Audo I. Longitudinal Clinical Follow-up and Genetic Spectrum of Patients With Rod-Cone Dystrophy Associated With Mutations in PDE6A and PDE6B. JAMA Ophthalmol 2019;Abstract
Importance: A precise phenotypic characterization of retinal dystrophies is needed for disease modeling as a basis for future therapeutic interventions. Objective: To compare genotype, phenotype, and structural changes in patients with rod-cone dystrophy (RCD) associated with mutations in PDE6A or PDE6B. Design, Setting, and Participants: In a retrospective cohort study conducted in Paris, France, from January 2007 to September 2017, 54 patients from a cohort of 1095 index patients with RCD underwent clinical examination, including personal and familial history, best-corrected visual acuity (BCVA), color vision, slitlamp examination, full-field electroretinography, kinetic visual fields (VFs), retinophotography, optical coherence tomography, near-infrared fundus autofluorescence, and short-wavelength fundus autofluorescence imaging. Genotyping was performed using microarray analysis, targeted next-generation sequencing, and Sanger sequencing validation with familial segregation when possible. Data were analyzed from September 1, 2017, to February 1, 2018. Clinical variables were subsequently analyzed in 2018. Main Outcomes and Measures: Phenotype and genotype comparison of patients carrying mutations in PDE6A or PDE6B. Results: Of the 54 patients included in the study, 19 patients of 17 families (11 women [58%]; mean [SD] age at diagnosis, 14.83 [10.63] years) carried pathogenic mutations in PDE6A, and 35 patients of 26 families (17 women [49%]; mean [SD] age at diagnosis, 21.10 [11.56] years) had mutations in PDE6B, accounting for prevalences of 1.6% and 2.4%, respectively. Among 49 identified genetic variants, 14 in PDE6A and 15 in PDE6B were novel. Overall, phenotypic analysis revealed no substantial differences between the 2 groups except for night blindness as a presenting symptom that was noted to be more prevalent in the PDE6A than PDE6B group (80% vs 37%, respectively; P = .005). The mean binocular BCVA and VF decrease over time (measured as mean individual slopes coefficients) was comparable between patients with PDE6A and PDE6B mutations: 0.04 (0.12) vs 0.02 (0.05) for BCVA (P = .89) and 14.33 (7.12) vs 13.27 (6.77) for VF (P = .48). Conclusions and Relevance: Mutations in PDE6A and PDE6B accounted for 1.6% and 2.4%, respectively, in a cohort of French patients with RCD. The functional and structural findings reported may constitute the basis of disease modeling that might be used for better prognostic estimation and candidate selection for photoreceptor therapeutic rescue.
Goldstein JM, Tabebordbar M, Zhu K, Wang LD, Messemer KA, Peacker B, Ashrafi Kakhki S, Gonzalez-Celeiro M, Shwartz Y, Cheng JKW, Xiao R, Barungi T, Albright C, Hsu Y-C, Vandenberghe LH, Wagers AJ. In Situ Modification of Tissue Stem and Progenitor Cell Genomes. Cell Rep 2019;27(4):1254-1264.e7.Abstract
In vivo delivery of genome-modifying enzymes holds significant promise for therapeutic applications and functional genetic screening. Delivery to endogenous tissue stem cells, which provide an enduring source of cell replacement during homeostasis and regeneration, is of particular interest. Here, we use a sensitive Cre/lox fluorescent reporter system to test the efficiency of genome modification following in vivo transduction by adeno-associated viruses (AAVs) in tissue stem and progenitor cells. We combine immunophenotypic analyses with in vitro and in vivo assays of stem cell function to reveal effective targeting of skeletal muscle satellite cells, mesenchymal progenitors, hematopoietic stem cells, and dermal cell subsets using multiple AAV serotypes. Genome modification rates achieved through this system reached >60%, and modified cells retained key functional properties. This study establishes a powerful platform to genetically alter tissue progenitors within their physiological niche while preserving their native stem cell properties and regulatory interactions.
Botten N, Hodges RR, Li D, Bair JA, Shatos MA, Utheim TP, Serhan CN, Dartt DA. Resolvin D2 elevates cAMP to increase intracellular [Ca] and stimulate secretion from conjunctival goblet cells. FASEB J 2019;33(7):8468-8478.Abstract
Under physiologic conditions, conjunctival goblet cells (CGCs) secrete mucins into the tear film to preserve ocular surface homeostasis. Specialized proresolving mediators (SPMs), like resolvins (Rvs), regulate secretion from CGCs and actively terminate inflammation. The purpose of this study was to determine if RvD2 stimulated mucin secretion and to investigate the cellular signaling components. Goblet cells were cultured from rat conjunctiva. Secretion was measured by an enzyme-linked lectin assay, change in intracellular [Ca] ([Ca]) using Fura-2, and cellular cAMP levels by ELISA. RvD2 (10-10 M) stimulated secretion, increased cellular cAMP levels and the [Ca]. RvD2-stimulated increase in [Ca] and secretion was blocked by Ca chelator 1,2-bis(2-aminophenoxy)ethane-,,','-tetraacetic acid tetrakis and the PKA inhibitor -[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride but not by the cAMP exchange protein inhibitor α-[2-(3-chlorophenyl)hydrazinylidene]-5-(1,1-dimethylethyl)-b-oxo-3-isoxazolepropanenitrile. Forskolin, 3-isobutyl-1-methylxanthine, and 8-bromo-cAMP (8-Br-cAMP) increased [Ca]. Increasing cAMP with 8-Br-cAMP inhibited the increase in [Ca] stimulated by the cAMP-independent agonist cholinergic agonist carbachol. In conclusion, RvD2 uses both cellular cAMP and [Ca] to stimulate glycoconjugate secretion from CGCs, but the interaction of cAMP and [Ca] is context dependent. Thus RvD2 likely assists in the maintenance of the mucous layer of the tear film to sustain ocular surface homeostasis and has potential as a novel treatment for dry eye disease.-Botten, N., Hodges, R. R., Li, D., Bair, J. A., Shatos, M. A., Utheim, T. P., Serhan, C. N., Dartt, D. A. Resolvin D2 elevates cAMP to increase intracellular [Ca] and stimulate secretion from conjunctival goblet cells.
Wang SV, Li N, Rice DS, Grosskreutz CL, Dryja TP, Prasanna G, Lii J, Gagne JJ. Using Healthcare Databases to Refine Understanding of Exploratory Associations Between Drugs and Progression of Open-Angle Glaucoma. Clin Pharmacol Ther 2019;106(4):874-883.Abstract
We sought to refine understanding about associations identified in prior studies between angiotensin-II receptor blockers, metformin, selective serotonin reuptake inhibitors, fibric-acid derivatives, or calcium channel blockers and progression to glaucoma filtration surgery for open-angle glaucoma (OAG). We used new-initiator, active-comparator cohort designs to investigate these drugs in two data sources. We adjusted for confounders using stabilized inverse-probability-of-treatment weights and evaluated results using "intention-to-treat" and "as-treated" follow-up approaches. In both data sources, Kaplan-Meier curves showed trends for more rapid progression to glaucoma filtration surgery in patients taking calcium channel blockers compared with thiazides with as-treated (MarketScan P = 0.15; Medicare P = 0.03) and intention-to-treat follow-up (MarketScan P < 0.01; Medicare P = 0.10). There was suggestion of delayed progression for selective serotonin reuptake inhibitor compared with tricyclic antidepressants in Medicare, which was not observed in MarketScan. Our study provided support for a relationship between calcium channel blockers and OAG progression but not for other investigated drugs.
Tsoka P, Barbisan PR, Kataoka K, Chen XN, Tian B, Bouzika P, Miller JW, Paschalis EI, Vavvas DG. NLRP3 inflammasome in NMDA-induced retinal excitotoxicity. Exp Eye Res 2019;181:136-144.Abstract
N-methyl-D-aspartate (NMDA)-induced excitotoxicity is an acute form of experimental retinal injury as a result of overactivation of glutamate receptors. NLRP3 (nucleotide-binding domain, leucine-rich-repeat containing family, pyrin domain containing-3) inflammasome, one of the most studied sensors of innate immunity, has been reported to play a critical role in retinal neurodegeneration with controversial implications regarding neuroprotection and cell death. Thus far, it has not been elucidated whether NMDA-mediated excitotoxicity can trigger NLRP3 inflammasome in vivo. Moreover, it is unknown if NLRP3 is beneficial or detrimental to NMDA-mediated retinal cell death. Here, we employed a murine model of NMDA-induced retinal excitotoxicity by administering 100 nmoles of NMDA intravitreally, which resulted in massive TUNEL (TdT-dUTP terminal nick-end labelling) cell death in all retinal layers and especially in retinal ganglion cells (RGCs) 24 h post injection. NMDA insult in the retina potentiates macrophage/microglia cell infiltration, primes the NLRP3 inflammasome in a transcription-dependent manner and induces the expression of interleukin-1β (IL-1β). However, despite NLRP3 inflammasome upregulation, systemic deletion of Nlrp3 or Casp1 (caspase-1) did not significantly alter the NMDA-induced, excitotoxicity-mediated TUNEL retinal cell death at 24 h (acute phase). Similarly, the deletion of the two aforementioned genes did not alter the survival of the Brn3a (brain-specific homeobox/POU domain protein 3A) RGCs in a significant way at 3- or 7-days post injection (long-term phase). Our results indicate that NMDA-mediated retinal excitotoxicity induces immune cell recruitment and NLRP3 inflammasome activity even though inflammasome-mediated neuroinflammation is not a leading contributing factor to cell death in this type of retinal injury.
Raghuram A, Cotter S, Gowrisankaran S, Kanji J, Howell DR, Meehan WP, Shah AS. Post-Concussion: Receded Near Point of Convergence is Not Diagnostic of Convergence Insufficiency. Am J Ophthalmol 2019;Abstract
PURPOSE: To determine the frequency of receded near point of convergence (NPC) in patients with chronic concussion-related symptoms, and among those with receded NPC to enumerate the frequency of convergence insufficiency and other oculomotor disorders. STUDY: Design: Retrospective cross-sectional study METHODS: Clinic charts were retrospectively reviewed for the prior 3.5 years to identify all patients <21 years old who were >28 days post-concussion, had chronic concussion-related symptoms, had normal visual acuity, and received a comprehensive sensorimotor examination. The frequency of receded NPC and oculomotor diagnoses were determined. RESULTS: Of the 83 eligible patients, 74 (89%) had receded NPC. Of these, 70 (95%) had oculomotor disorders; 30 (41%) had disorders of accommodation only, 21 (28%) had convergence insufficiency and accommodation deficits, and 6 (8%) had convergence insufficiency only. Six (8%) had a convergence deficit other than convergence insufficiency (all with concurrent accommodative disorders), 4 (5%) had both a non-specific vergence dysfunction and accommodation deficits, 2 (3%) had convergence excess only, and 1 (1%) had both convergence excess and accommodative deficits. CONCLUSION: A receded NPC was present in the majority of young patients with chronic post-concussion symptoms. Associated with numerous underlying oculomotor dysfunctions, the clinical finding of a receded NPC is not synonymous with the diagnosis of convergence insufficiency. Because treatment options for the various oculomotor dysfunctions differ, it is prudent that these patients undergo a thorough examination of their vergence and accommodative systems so that an accurate diagnosis can be made and appropriate treatment prescribed.
Marmalidou A, Palioura S, Dana R, Kheirkhah A. Medical and surgical management of conjunctivochalasis. Ocul Surf 2019;Abstract
Conjunctivochalasis (CCH) is a bilateral conjunctival condition characterized by loose, redundant conjunctival folds, typically in the inferior bulbar conjunctiva. It is a common cause of ocular irritation, especially in older age. For asymptomatic CCH, no treatment is necessary. For treatment of symptomatic CCH, however, a variety of medical and surgical approaches are currently available, which will be thoroughly appraised in this review article. The first step in the management is medical therapy, which involves enhanced lubrication and use of anti-inflammatory medications. In refractory cases, a surgical approach may be undertaken for symptom relief. Several techniques have been described for this, with varying success rates. These include conjunctival cauterization, conjunctival excision, scleral fixation of the conjunctiva, conjunctival ligation, laser conjunctivoplasty, and radiowave electrosurgery. Among these, conjunctival cauterization and excision of the redundant conjunctiva, with or without tissue grafting, have gained popularity.
Hutcheon AEK, Zieske JD, Guo X. 3D in vitro model for human corneal endothelial cell maturation. Exp Eye Res 2019;184:183-191.Abstract
Corneal endothelium is a cellular monolayer positioned on the Descemet's membrane at the anterior cornea, and it plays a critical role in maintaining corneal clarity. Our present study examines the feasibility of utilizing our 3-dimensional (3D) corneal stromal construct, which consists of human corneal fibroblasts (HCF) and their self-assembled matrix, to observe the development and maturation of human corneal endothelial cells (HCEndoCs) in a co-culture model. Three-dimensional HCF constructs were created by growing the HCFs on Transwell membranes in Eagles' minimum essential medium (EMEM) + 10% FBS + 0.5 mM Vitamin C (VitC) for about 4 weeks. HCEndoCs, either primary (pHCEndoC) or cell line (HCEndoCL), were either seeded in chamber slides, directly on the Transwell membranes, or on the 3D HCF constructs and cultivated for 5 days or 2 weeks. The HCEndoCs that were seeded directly on the Transwell membranes were exposed indirectly to HCF by culturing the HCF on the plate beneath the membrane. Cultures were examined for morphology and ultrastructure using light and transmission electron microscopy (TEM). In addition, indirect-immunofluorescence microscopy (IF) was used to examine tight junction formation (ZO-1), maturation (ALDH1A1), basement membrane formation (Laminin), cell proliferation (Ki67), cell death (caspase-3), and fibrotic response (CTGF). As expected, both pHCEndoCs and HCEndoCLs formed monolayers on the constructs; however, the morphology of the HCEndoCLs appeared to be similar to that seen in vivo, uniform and closely packed, whereas the pHCEndoCs remained elongated. The IF data showed that laminin localization was present in the HCEndoCs' cytoplasm as cell-cell contact increased, and when they were grown in the 3D co-culture, the beginnings of what appears to be a continuous DM-like structure was observed. In addition, in co-cultures, ALDH1A1-positive HCEndoCs were present, ZO-1 expression localized within the tight junctions, minimal numbers of HCEndoCs were Ki67-or Caspase-3-positive, and CTGF was positive in both the HCEndoCs cytoplasm and the matrix of the co-culture. Also, laminin localization was stimulated in HCEndoCs upon indirect stimuli secreted by HCF. The present data suggests our 3D co-culture model is useful for studying corneal endothelium maturation in vitro since the co-culture promotes new DM-like formation, HCEndoCs develop in vivo-like characteristics, and the fibrotic response is activated. Our current findings are applicable to understanding the implications of corneal endothelial injection therapy, such as if the abnormal DM has to be removed from the patient, the newly injected endothelial cells will seed onto the wound area and deposit a new DM-like membrane. However, caution should be observed and as much of the normal DM should be left intact since removal of the DM can cause a posterior stromal fibrotic response.
Deiner MS, McLeod SD, Wong J, Chodosh J, Lietman TM, Porco TC. Google Searches and Detection of Conjunctivitis Epidemics Worldwide. Ophthalmology 2019;126(9):1219-1229.Abstract
PURPOSE: Epidemic and seasonal infectious conjunctivitis outbreaks can impact education, workforce, and economy adversely. Yet conjunctivitis typically is not a reportable disease, potentially delaying mitigating intervention. Our study objective was to determine if conjunctivitis epidemics could be identified using Google Trends search data. DESIGN: Search data for conjunctivitis-related and control search terms from 5 years and countries worldwide were obtained. Country and term were masked. Temporal scan statistics were applied to identify candidate epidemics. Candidates then were assessed for geotemporal concordance with an a priori defined collection of known reported conjunctivitis outbreaks, as a measure of sensitivity. PARTICIPANTS: Populations by country that searched Google's search engine using our study terms. MAIN OUTCOME MEASURES: Percent of known conjunctivitis outbreaks also found in the same country and period by our candidate epidemics, identified from conjunctivitis-related searches. RESULTS: We identified 135 candidate conjunctivitis epidemic periods from 77 countries. Compared with our a priori defined collection of known reported outbreaks, candidate conjunctivitis epidemics identified 18 of 26 (69% sensitivity) of the reported country-wide or island nationwide outbreaks, or both; 9 of 20 (45% sensitivity) of the reported region or district-wide outbreaks, or both; but far fewer nosocomial and reported smaller outbreaks. Similar overall and individual sensitivity, as well as specificity, were found on a country-level basis. We also found that 83% of our candidate epidemics had start dates before (of those, 20% were more than 12 weeks before) their concurrent reported outbreak's report issuance date. Permutation tests provided evidence that on average, conjunctivitis candidate epidemics occurred geotemporally closer to outbreak reports than chance alone suggests (P < 0.001) unlike control term candidates (P = 0.40). CONCLUSIONS: Conjunctivitis outbreaks can be detected using temporal scan analysis of Google search data alone, with more than 80% detected before an outbreak report's issuance date, some as early as the reported outbreak's start date. Future approaches using data from smaller regions, social media, and more search terms may improve sensitivity further and cross-validate detected candidates, allowing identification of candidate conjunctivitis epidemics from Internet search data potentially to complementarily benefit traditional reporting and detection systems to improve epidemic awareness.
Baker CW, Glassman AR, Beaulieu WT, Antoszyk AN, Browning DJ, Chalam KV, Grover S, Jampol LM, Jhaveri CD, Melia M, Stockdale CR, Martin DF, Sun JK, Sun JK. Effect of Initial Management With Aflibercept vs Laser Photocoagulation vs Observation on Vision Loss Among Patients With Diabetic Macular Edema Involving the Center of the Macula and Good Visual Acuity: A Randomized Clinical Trial. JAMA 2019;Abstract
Importance: Intravitreous injections of antivascular endothelial growth factor agents are effective for treating diabetic macular edema (DME) involving the center of the macula (center-involved DME [CI-DME]) with visual acuity impairment (20/32 or worse). The best approach to treating patients with CI-DME and good visual acuity (20/25 or better) is unknown. Objective: To compare vision loss at 2 years among eyes initially managed with aflibercept, laser photocoagulation, or observation. Design, Setting, and Participants: Randomized clinical trial conducted at 91 US and Canadian sites among 702 adults with type 1 or type 2 diabetes. Participants had 1 study eye with CI-DME and visual acuity of 20/25 or better. The first participant was randomized on November 8, 2013, and the final date of follow-up was September 11, 2018. Interventions: Eyes were randomly assigned to 2.0 mg of intravitreous aflibercept (n = 226) as frequently as every 4 weeks, focal/grid laser photocoagulation (n = 240), or observation (n = 236). Aflibercept was required for eyes in the laser photocoagulation or observation groups that had decreased visual acuity from baseline by at least 10 letters (≥ 2 lines on an eye chart) at any visit or by 5 to 9 letters (1-2 lines) at 2 consecutive visits. Main Outcomes and Measures: The primary outcome was at least a 5-letter visual acuity decrease from baseline at 2 years. Antiplatelet Trialists' Collaboration adverse events (defined as myocardial infarction, stroke, or vascular or unknown death) were reported. Results: Among 702 randomized participants (mean age, 59 years; 38% female [n=264]), 625 of 681 (92% excluding deaths) completed the 2-year visit. For eyes with visual acuity that decreased from baseline, aflibercept was initiated in 25% (60/240) and 34% (80/326) in the laser photocoagulation and observation groups, respectively. At 2 years, the percentage of eyes with at least a 5-letter visual acuity decrease was 16% (33/205), 17% (36/212), and 19% (39/208) in the aflibercept, laser photocoagulation, and observation groups, respectively (aflibercept vs laser photocoagulation risk difference, -2% [95% CI, -9% to 5%]; relative risk, 0.88 [95% CI, 0.57-1.35; P = .79]; aflibercept vs observation risk difference, -3% [95% CI, -11% to 4%]; relative risk, 0.83 [95% CI, 0.55-1.27; P = .79]; laser photocoagulation vs observation risk difference, -1% [95% CI, -9% to 6%]; relative risk, 0.95 [95% CI, 0.64-1.41; P = .79]). Antiplatelet Trialists' Collaboration vascular events occurred in 15 (7%), 13 (5%), and 8 (3%) participants in the aflibercept, laser photocoagulation, and observation groups. Conclusions and Relevance: Among eyes with CI-DME and good visual acuity, there was no significant difference in vision loss at 2 years whether eyes were initially managed with aflibercept or with laser photocoagulation or observation and given aflibercept only if visual acuity worsened. Observation without treatment unless visual acuity worsens may be a reasonable strategy for CI-DME. Trial Registration: Identifier: NCT01909791.