Increased intraocular pressure (IOP) represents a major risk factor for glaucoma, a prevalent eye disease characterized by death of retinal ganglion cells; lowering IOP is the only proven treatment strategy to delay disease progression. The main determinant of IOP is the equilibrium between production and drainage of aqueous humor, with compromised drainage generally viewed as the primary contributor to dangerous IOP elevations. Drainage occurs through two pathways in the anterior segment of the eye called conventional and uveoscleral. To gain insights into the cell types that comprise these pathways, we used high-throughput single-cell RNA sequencing (scRNAseq). From ∼24,000 single-cell transcriptomes, we identified 19 cell types with molecular markers for each and used histological methods to localize each type. We then performed similar analyses on four organisms used for experimental studies of IOP dynamics and glaucoma: cynomolgus macaque (), rhesus macaque (), pig (), and mouse (). Many human cell types had counterparts in these models, but differences in cell types and gene expression were evident. Finally, we identified the cell types that express genes implicated in glaucoma in all five species. Together, our results provide foundations for investigating the pathogenesis of glaucoma and for using model systems to assess mechanisms and potential interventions.

BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder characterized by benign hamartomas occurring in multiple organ systems including the brain, kidneys, heart, lungs, liver, skin, and the eyes. Typical retinal findings associated with TSC include astrocytic hamartoma and achromic patch. While rare cases of cataract occurring in the setting of TSC have been reported, this is the first analysis of a large series of individuals with TSC that aims to quantify the frequency of this finding and to describe its clinical and genetic associations. MATERIALS AND METHODS: This is a retrospective chart review of 244 patients from the Herscot Center for Tuberous Sclerosis Complex at the Massachusetts General Hospital who underwent complete ophthalmic examination. We describe the clinical and genetic findings in five individuals with TSC and juvenile cataract. RESULTS: Four of five cases (80%) were unilateral. The cataract was described as having an anterior subcapsular component in 3 of 5 cases (60%). Three individuals (60%) underwent lensectomy with intraocular lens (IOL) implant and two individuals (40%) were observed. Genetic testing revealed a known disease-causing mutation in in 100% of cases. CONCLUSIONS: Recent evidence suggests that mTOR signaling may play a role in cataract formation which could explain the relatively high incidence of juvenile cataract in this population. Juvenile cataract is a potentially under-recognized ocular manifestation of TSC.

Long-lived memory T-helper 17 (Th17) cells actively mediate the chronic inflammation in autoimmune disorders, including dry eye disease (DED). The mechanisms responsible for the maintenance and reactivation of these cells in autoimmunity have been subject of investigation. However, the process through which memory Th17 are generated from their effector precursors remains to be elucidated. Herein, using our murine model of DED, we detect a linear transition from effector-to-memory Th17 cells during the abatement phase of acute inflammation, which is accompanied by persistently high levels of IL-23 and diminished levels of IL-2. In addition, in vitro culture of effector Th17 cells derived from the DED animals with IL-23, but not IL-2, leads to significant generation of memory Th17 cells, along with upregulated expression levels of IL-7R and IL-15R by these cells. Furthermore, supplementation of IL-2 abolishes and blockade of IL-2 enhances IL-23-induced generation of memory Th17 cells in vitro. Finally, in vivo blockade of IL-23 signaling during the contraction phase of primary response inhibits the generation of memory Th17 cells from their effector precursors. Together, our data demonstrate a new dichotomy between IL-23 and IL-2 in driving effector Th17 cells into the memory pool in autoimmune-mediated ocular surface inflammation.

PURPOSE: To review the literature on the efficacy of intense pulsed light (IPL) on the eyelids in the management of meibomian gland disease (MGD) and meibomian gland-related ocular surface disease. METHODS: A literature search was last conducted on May 15, 2019, in the PubMed and Cochrane Library databases for English-language original research that assessed the effect of IPL on MGD in adult patients. Thirty-three articles were identified, and 12 studies were determined to be relevant to the criteria outlined for assessment. The panel methodologist (V.K.A.) assigned a level of evidence rating to each study; 4 studies were rated level II, and 8 studies were rated level III. Five studies had potential conflicts of interest and design limitations that affected interpretation of results. RESULTS: All studies documented improvement in clinically meaningful metrics, including tear breakup time (TBUT), corneal staining and eyelid margin measurements, meibum quality, meibomian gland expressability, ocular surface disease index (OSDI), and standard patient evaluation of eye dryness (SPEED) questionnaire scores. Side effects were relatively uncommon but included discomfort, cutaneous erythema, blistering, eyelash loss, and floaters; these were uniformly self-limited. CONCLUSIONS: Although methodological limitations and potential conflicts of interest in some studies raised concern, the existing body of literature demonstrates improvements in the signs and symptoms of MGD after IPL therapy.

In visual search tasks, observers look for targets among distractors. In the lab, this often takes the form of multiple searches for a simple shape that may or may not be present among other items scattered at random on a computer screen (e.g., Find a red T among other letters that are either black or red.). In the real world, observers may search for multiple classes of target in complex scenes that occur only once (e.g., As I emerge from the subway, can I find lunch, my friend, and a street sign in the scene before me?). This article reviews work on how search is guided intelligently. I ask how serial and parallel processes collaborate in visual search, describe the distinction between search templates in working memory and target templates in long-term memory, and consider how searches are terminated.

Why ocular mucosa is paucibacterial is unknown. Many different mechanisms have been suggested but the comprehensive experimental studies are sparse. We found that a deficiency in L-plastin (LCP1), an actin bundling protein, resulted in an ocular commensal overgrowth, characterized with increased presence of conjunctival spp. The commensal overgrowth correlated with susceptibility to -induced keratitis. L-plastin knock-out (KO) mice displayed elevated bacterial burden in the -infected corneas, altered inflammatory responses, and compromised bactericidal activity. Mice with ablation of LPL under the LysM Cre ( ) and S100A8 Cre ( ) promoters had a similar phenotype to the LPL KOs mice. In contrast, infected mice did not display elevated susceptibility to infection, implicating the myeloid L-plastin-sufficient cells (e.g., macrophages and neutrophils) in maintaining ocular homeostasis. Mechanistically, the elevated commensal burden and the susceptibility to infection were linked to defects in neutrophil frequencies at steady state and during infection and compromised bactericidal activities upon priming. Macrophage exposure to commensal organisms primed neutrophil responses to , augmenting PMN bactericidal capacity in an L-plastin dependent manner. Cumulatively, our data highlight the importance of neutrophils in controlling ocular paucibacteriality, reveal molecular and cellular events involved in the process, and suggest a link between commensal exposure and resistance to infection.

PURPOSE: The purpose of this assessment is to evaluate the accuracy of autorefraction compared with cycloplegic retinoscopy in children. METHODS: Literature searches were last conducted in October 2019 in the PubMed and the Cochrane Library databases for studies published in English. The combined searches yielded 118 citations, of which 53 were reviewed in full text. Of these, 31 articles were deemed appropriate for inclusion in this assessment and subsequently assigned a level of evidence rating by the panel methodologists. Four articles were rated level I, 11 were rated level II, and 16 were rated level III articles. The 16 level III articles were excluded from this review. RESULTS: Thirteen of the 15 studies comparing cycloplegic autorefraction with cycloplegic retinoscopy found a mean difference in spherical equivalent or sphere of less than 0.5 diopters (D); most were less than 0.25 D. Even lower mean differences were found when evaluating the cylindrical component of cycloplegic autorefraction versus cycloplegic retinoscopy. Despite low mean variability, there was significant individual measurement variability; the 95% limits of agreement were wide and included clinically relevant differences. Comparisons of noncycloplegic with cycloplegic autorefractions found that noncyloplegic refraction tends to over minus by 1 to 2 D. CONCLUSIONS: Cycloplegic autorefraction is appropriate to use in pediatric population-based studies. Cycloplegic retinoscopy can be valuable in individual clinical cases to confirm the accuracy of cycloplegic autorefraction, particularly when corrected visual acuity is worse than expected or the autorefraction results are not consistent with expected findings.

PURPOSE: To document a unique case of a corneal/conjunctival epithelial inclusion cyst located in the orbicularis oculi muscle with a comprehensive review of variant conjunctival cysts and simulating conditions. METHODS: Clinicopathologic case report with detailed histopathologic and immunohistochemical evaluation for cytokeratins combined with a tabulation of mimicking lesions and relevant literature citations. RESULTS: A 59-year-old man experienced severe blunt left periorbital trauma that resulted in a limbal partial-thickness corneal wound with an associated epithelial abrasion and a full-thickness eyelid laceration extending from the superior fornix to the margin. Several months after surgical repair of the eyelid a cyst appeared in the superior pretarsal skin. Histopathologic and immunohistochemical investigations supplied data suggesting that the cyst had a high probability of a corneoscleral limbal stem cell origin. Distinctive features of the lesion are contrasted with those of allied or simulating cysts. CONCLUSIONS: Stem cells are now believed to be located at the corneoscleral limbus, in the inferior fornix, in the medial canthal region, and at the eyelid margin where transitions from conjunctival epithelium to epidermal epithelium occur. Due to their replicative, hardy and robust nature, stem cells displaced to alien environments are most likely to survive and produce cysts. The cyst's corneal-type cytologic characteristics, the absence of goblet cells, and the expression of a broad spectrum of cytokeratin biomarkers in the current case give support to the proposal that limbal stem cells in the region of the corneal laceration were displaced to the eyelid orbicularis muscle and were responsible for this most extraordinary cyst. Comparison with other epithelial cystic linings lends further evidence for this conclusion.

The outer segments (OS) of rod and cone photoreceptor cells are specialized sensory cilia that contain hundreds of opsin-loaded stacked membrane disks that enable phototransduction. The biogenesis of these disks is initiated at the OS base, but the driving force has been debated. Here, we studied the function of the protein encoded by the photoreceptor-specific gene , which is mutated in inherited retinal dystrophy (RP54). We demonstrate that C2orf71/PCARE (photoreceptor cilium actin regulator) can interact with the Arp2/3 complex activator WASF3, and efficiently recruits it to the primary cilium. Ectopic coexpression of PCARE and WASF3 in ciliated cells results in the remarkable expansion of the ciliary tip. This process was disrupted by small interfering RNA (siRNA)-based down-regulation of an actin regulator, by pharmacological inhibition of actin polymerization, and by the expression of PCARE harboring a retinal dystrophy-associated missense mutation. Using human retinal organoids and mouse retina, we observed that a similar actin dynamics-driven process is operational at the base of the photoreceptor OS where the PCARE module and actin colocalize, but which is abrogated in mice. The observation that several proteins involved in retinal ciliopathies are translocated to these expansions renders it a potential common denominator in the pathomechanisms of these hereditary disorders. Together, our work suggests that PCARE is an actin-associated protein that interacts with WASF3 to regulate the actin-driven expansion of the ciliary membrane at the initiation of new outer segment disk formation.

We report the surgical management of a patient with bilateral anterior lenticonus due to Alport syndrome using femtosecond laser-assisted cataract surgery (FLACS) and the Optiwave Refractive Analysis (ORA) system. A 38-year-old man with Alport syndrome presented to our department with visual loss due to anterior lenticonus in both eyes. Adjustments during bilateral FLACS were performed with the software's calipers to manually delineate the anterior capsulotomy. Multifocal toric intraocular lenses (IOLs) were selected and placed in the posterior chamber with the aid of intraoperative aberrometry. The intended postoperative positioning parameters for the IOL as well as the planned visual acuity and refraction were achieved. The implementation of FLACS and intraoperative wavefront aberrometry is a safe and useful surgical approach for the management of cataract in challenging cases such as patients with anterior lenticonus due to Alport syndrome.

The prevalence as well as the severity of dry eye disease increase with age. Memory T helper 17 (Th17) cells (CD4IL-17ACD44) drive the chronic and relapsing course of dry eye disease. Here, we investigated the contribution of memory Th17 cells to age-related dry eye disease, and evaluated memory Th17 cell depletion with anti-IL-15 antibody as a strategy to abrogate the severe exacerbations of dry eye disease observed in aged mice. After initial exposure to desiccating stress, aged mice maintained higher frequencies of memory Th17 cells in the draining lymph nodes relative to young mice. Upon secondary exposure to desiccating stress, aged mice developed more severe corneal epitheliopathy than young mice, which is associated with increased local frequencies of Th17 cells (CD4IL-17A). Treatment with anti-IL-15 antibody decreased the enlarged memory Th17 pool in aged mice to frequencies comparable with young mice. Furthermore, anti-IL-15-treated mice showed significantly reduced conjunctival infiltration of Th17 cells and lower corneal fluorescein staining scores compared with saline-treated control mice. Our data suggest that age-related increases in the memory Th17 compartment predispose aged mice toward the development of severe corneal epithelial disease after exposure to a dry environment. Selectively targeting memory Th17 cells may be a viable therapeutic approach in the treatment of age-related dry eye disease.

Dynamic modification of nuclear and cytoplasmic proteins with O-linked β-N-acetylglucosamine (O-GlcNAc) plays an important role in orchestrating the transcriptional activity of eukaryotic cells. Here, we report that the O-GlcNAc modification contributes to maintaining ocular surface epithelial homeostasis by promoting mucin biosynthesis and barrier function. We found that induction of human corneal epithelial cell differentiation stimulated the global transfer of O-GlcNAc to both nuclear and cytosolic proteins. Inflammatory conditions, on the other hand, were associated with a reduction in the expression of O-GlcNAc transferase at the ocular surface epithelia. Loss- and gain-of-function studies using small interfering RNA targeting O-GlcNAc transferase, or Thiamet G, a selective inhibitor of O-GlcNAc hydrolase, respectively, revealed that the presence of O-GlcNAc was necessary to promote glycocalyx barrier function. Moreover, we found that Thiamet G triggered a correlative increase in both surface expression of MUC16 and apical epithelial cell area while reducing paracellular permeability. Collectively, these results identify intracellular protein O-glycosylation as a novel pathway responsible for promoting the terminal differentiation of human corneal epithelial cells.

Botulinum toxin is an important treatment for many conditions in ophthalmology, including strabismus, nystagmus, blepharospasm, hemifacial spasm, spastic and congenital entropion, corneal exposure, and persistent epithelial defects. The mechanism of action of botulinum toxin for both strabismus and nystagmus is the neuromuscular blockade and transient paralysis of extraocular muscles, but when botulinum toxin is used for some forms of strabismus, a single injection can convey indefinite benefits. There are two unique mechanisms of action that account for the long-term effect on ocular alignment: (1) the disruption of a balanced system of agonist-antagonist extraocular muscles and (2) the reestablishment of central control of alignment by the binocular visual system. For other ocular conditions, botulinum toxin acts through transient paralysis of periocular muscles. Botulinum toxin is a powerful tool in ophthalmology, achieving its therapeutic effects by direct neuromuscular blockade of extraocular and periocular muscles and by unique mechanisms related to the underlying structure and function of the visual system.

PURPOSE: The origin of blood in glaucoma-related disc hemorrhages (DH) remains unknown. A prior clinic-based study of primary open-angle glaucoma (POAG)-related DH showed that they had grayscale pixel intensities more similar to blood from retinal macroaneurysms and adjacent retinal arterioles than to blood from retinal vein occlusions or adjacent retinal venules, suggesting an arterial source. Here we assessed the densitometric profile of DH from fundus photographs in the Ocular Hypertension Treatment Study (OHTS). DESIGN: Retrospective cross-sectional study of prospectively collected images. METHODS: Stereo disc photographs of 161 DH events from 83 OHTS participants (mean age [standard deviation (SD)]: 65.6 [9.2] years; 46.6% female; 13.0% black race) were imported into ImageJ to measure densitometry differences (adjacent arterioles minus DH [ΔA] or venules minus DH [ΔV]). Their size as percentage of disc area, ratio of length to midpoint width, and location relative to the disc margin were also analyzed. We performed t tests to compare ΔA and ΔV, analysis of variance to compare ΔA and ΔV across DH recurrent events, and multivariable linear regression to identify determinants of ΔA and ΔV. RESULTS: Mean (SD) ΔA and ΔV were -2.2 (8.7) and -11.4 (9.7) pixel intensity units, respectively (P < .001). ΔA and ΔV each did not differ significantly across recurrence of DH (P ≥ .92) or between DH events with and without POAG (P ≥ .26). CONCLUSIONS: OHTS DH had densitometric measurements more similar in magnitude to adjacent arterioles than venules, supporting an arterial origin for DH. Vascular dysregulation may contribute to disc hemorrhage formation in ocular hypertension.

Refractive errors, in particular myopia, are a leading cause of morbidity and disability worldwide. Genetic investigation can improve understanding of the molecular mechanisms that underlie abnormal eye development and impaired vision. We conducted a meta-analysis of genome-wide association studies (GWAS) that involved 542,934 European participants and identified 336 novel genetic loci associated with refractive error. Collectively, all associated genetic variants explain 18.4% of heritability and improve the accuracy of myopia prediction (area under the curve (AUC) = 0.75). Our results suggest that refractive error is genetically heterogeneous, driven by genes that participate in the development of every anatomical component of the eye. In addition, our analyses suggest that genetic factors controlling circadian rhythm and pigmentation are also involved in the development of myopia and refractive error. These results may enable the prediction of refractive error and the development of personalized myopia prevention strategies in the future.

Although the prevalence of all stages of diabetic retinopathy has been declining since 1980 in populations with improved diabetes control, the crude prevalence of visual impairment and blindness caused by diabetic retinopathy worldwide increased between 1990 and 2015, largely because of the increasing prevalence of type 2 diabetes, particularly in low-income and middle-income countries. Screening for diabetic retinopathy is essential to detect referable cases that need timely full ophthalmic examination and treatment to avoid permanent visual loss. In the past few years, personalised screening intervals that take into account several risk factors have been proposed, with good cost-effectiveness ratios. However, resources for nationwide screening programmes are scarce in many countries. New technologies, such as scanning confocal ophthalmology with ultrawide field imaging and handheld mobile devices, teleophthalmology for remote grading, and artificial intelligence for automated detection and classification of diabetic retinopathy, are changing screening strategies and improving cost-effectiveness. Additionally, emerging evidence suggests that retinal imaging could be useful for identifying individuals at risk of cardiovascular disease or cognitive impairment, which could expand the role of diabetic retinopathy screening beyond the prevention of sight-threatening disease.

PURPOSE: To identify temporal and geographic trends in private equity (PE)-backed acquisitions of ophthalmology and optometry practices in the United States. DESIGN: A cross-sectional study using private equity acquisition and investment data from January 1, 2012, through October 20, 2019. PARTICIPANTS: A total of 228 PE acquisitions of ophthalmology and optometry practices in the United States between 2012 and 2019. METHODS: Acquisition and financial investment data were compiled from 6 financial databases, 4 industry news outlets, and publicly available press releases from PE firms or platform companies. MAIN OUTCOME MEASURES: Yearly trends in ophthalmology and optometry acquisitions, including number of total acquisitions, clinical locations, and providers of acquired practices as well as subsequent sales, median holding period, geographic footprint, and financing status of each platform company. RESULTS: A total of 228 practices associated with 1466 clinical locations and 2146 ophthalmologists or optometrists were acquired by 29 PE-backed platform companies. Of these acquisitions, 127, 9, and 92 were comprehensive or multispecialty, retina, and optometry practices, respectively. Acquisitions increased rapidly between 2012 and 2019: 42 practices were acquired between 2012 and 2016 compared to 186 from 2017 through 2019. Financing rounds of platform companies paralleled temporal acquisition trends. Three platform companies, comprising 60% of platforms formed before 2016, were subsequently sold or recapitalized to new PE investors by the end of this study period with a median holding period of 3.5 years. In terms of geographic distribution, acquisitions occurred in 40 states with most PE firms developing multistate platform companies. New York and California were the 2 states with the greatest number of PE acquisitions with 22 and 19, respectively. CONCLUSIONS: Private equity-backed acquisitions of ophthalmology and optometry practices have increased rapidly since 2012, with some platform companies having already been sold or recapitalized to new investors. Additionally, private equity-backed platform companies have developed both regionally focused and multistate models of add-on acquisitions. Future research should assess the impact of PE investment on patient, provider, and practice metrics, including health outcomes, expenditures, procedural volume, and staff employment.

PURPOSE: To evaluate outcomes of bilateral cataract surgery in infants 1 to 7 months of age performed by Infant Aphakia Treatment Study (IATS) investigators during IATS recruitment and to compare them with IATS unilateral outcomes. DESIGN: Retrospective case series review at 10 IATS sites. PARTICIPANTS: The Toddler Aphakia and Pseudophakia Study (TAPS) is a registry of children treated by surgeons who participated in the IATS. METHODS: Children underwent bilateral cataract surgery with or without intraocular lens (IOL) placement during IATS enrollment years 2004 through 2010. MAIN OUTCOME MEASURES: Visual acuity (VA), strabismus, adverse events (AEs), and reoperations. RESULTS: One hundred seventy-eight eyes (96 children) were identified with a median age of 2.5 months (range, 1-7 months) at the time of cataract surgery. Forty-two eyes (24%) received primary IOL implantation. Median VA of the better-seeing eye at final study visit closest to 5 years of age with optotype VA testing was 0.35 logarithm of the minimum angle of resolution (logMAR; optotype equivalent, 20/45; range, 0.00-1.18 logMAR) in both aphakic and pseudophakic children. Corrected VA was excellent (<20/40) in 29% of better-seeing eyes, 15% of worse-seeing eyes. One percent showed poor acuity (≥20/200) in the better-seeing eye, 12% in the worse-seeing eye. Younger age at surgery and smaller (<9.5 mm) corneal diameter at surgery conferred an increased risk for glaucoma or glaucoma suspect designation (younger age: odds ratio [OR], 1.44; P = 0.037; and smaller cornea: OR, 3.95; P = 0.045). Adverse events also were associated with these 2 variables on multivariate analysis (younger age: OR, 1.36; P = 0.023; and smaller cornea: OR, 4.78; P = 0.057). Visual axis opacification was more common in pseudophakic (32%) than aphakic (8%) eyes (P = 0.009). Unplanned intraocular reoperation occurred in 28% of first enrolled eyes (including glaucoma surgery in 10%). CONCLUSIONS: Visual acuity after bilateral cataract surgery in infants younger than 7 months is good, despite frequent systemic and ocular comorbidities. Although aphakia management did not affect VA outcome or AE incidence, IOL placement increased the risk of visual axis opacification. Adverse events and glaucoma correlated with a younger age at surgery and glaucoma correlated with the presence of microcornea.

An international, expert led consensus initiative was set up by the Collaborative Ocular Tuberculosis Study (COTS) group to develop systematic, evidence, and experience-based recommendations for the treatment of ocular TB using a modified Delphi technique process. In the first round of Delphi, the group identified clinical scenarios pertinent to ocular TB based on five clinical phenotypes (anterior uveitis, intermediate uveitis, choroiditis, retinal vasculitis, and panuveitis). Using an interactive online questionnaires, guided by background knowledge from published literature, 486 consensus statements for initiating ATT were generated and deliberated amongst 81 global uveitis experts. The median score of five was considered reaching consensus for initiating ATT. The median score of four was tabled for deliberation through Delphi round 2 in a face-to-face meeting. This report describes the methodology adopted and followed through the consensus process, which help elucidate the guidelines for initiating ATT in patients with choroidal TB.