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Barrero-Castillero A, Corwin BK, VanderVeen DK, Wang JC. Workforce Shortage for Retinopathy of Prematurity Care and Emerging Role of Telehealth and Artificial Intelligence. Pediatr Clin North Am 2020;67(4):725-733.Abstract
Retinopathy of prematurity (ROP) is the leading cause of childhood blindness in very-low-birthweight and very preterm infants in the United States. With improved survival of smaller babies, more infants are at risk for ROP, yet there is an increasing shortage of providers to screen and treat ROP. Through a literature review of new and emerging technologies, screening criteria, and analysis of a national survey of pediatric ophthalmologists and retinal specialists, the authors found the shortage of ophthalmology workforce for ROP a serious and growing concern. When used appropriately, emerging technologies have the potential to mitigate gaps in the ROP workforce.
Gagrani M, Garg I, Ghate D. Surgical interventions for primary congenital glaucoma. Cochrane Database Syst Rev 2020;8:CD008213.Abstract
BACKGROUND: Primary congenital glaucoma (PCG) is an optic neuropathy with high intraocular pressure (IOP) that manifests within the first few years of a child's life and is not associated with other systemic or ocular abnormalities. PCG results in considerable morbidity even in high-income countries. OBJECTIVES: To compare the effectiveness and safety of different surgical techniques for PCG. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2020, Issue 4); Ovid MEDLINE; Embase.com; PubMed; metaRegister of Controlled Trials (mRCT) (last searched 23 June 2014); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search. We last searched the electronic databases on 27 April 2020. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs comparing different surgical interventions in children under five years of age with PCG. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. MAIN RESULTS: We included 16 trials (13 RCTs and three quasi-RCTs) with 587 eyes in 446 children. Eleven (69%) trials were conducted in Egypt and the Middle East, three in India, and two in the USA. All included trials involved children younger than five years of age, with follow-up ranging from six to 80 months. The interventions compared varied across trials. Three trials (on 68 children) compared combined trabeculotomy and trabeculectomy (CTT) with trabeculotomy. Meta-analysis of these trials suggests there may be little to no evidence of a difference between groups in mean IOP (mean difference (MD) 0.27 mmHg, 95% confidence interval (CI) -0.74 to 1.29; 88 eyes; 2 studies) and surgical success (risk ratio (RR) 1.01, 95% CI 0.90 to 1.14; 102 eyes; 3 studies) at one year postoperatively. We assessed the certainty of evidence as very low for these outcomes, downgrading for risk of bias (-1) and imprecision (-2). Hyphema was the most common adverse outcome in both groups (no meta-analysis due to considerable heterogeneity; I = 83%). Two trials (on 39 children) compared viscotrabeculotomy to conventional trabeculotomy. Meta-analysis of 42 eyes suggests there is no evidence of between groups difference in mean IOP (MD -1.64, 95% CI -5.94 to 2.66) and surgical success (RR 1.11, 95% CI 0.70 to 1.78) at six months postoperatively. We assessed the certainty of evidence as very low, downgrading for risk of bias and imprecision due to small sample size. Hyphema was the most common adverse outcome (38% in viscotrabeculotomy and 28% in conventional trabeculotomy), with no evidence of difference difference (RR 1.33, 95% CI 0.63 to 2.83). Two trials (on 95 children) compared microcatheter-assisted 360-degree circumferential trabeculotomy to conventional trabeculotomy. Meta-analysis of two trials suggests that mean IOP may be lower in the microcatheter group at six months (MD -2.44, 95% CI -3.69 to -1.19; 100 eyes) and at 12 months (MD -1.77, 95% CI -2.92 to -0.63; 99 eyes); and surgical success was more likely to be achieved in the microcatheter group compared to the conventional trabeculotomy group (RR 1.59, 95% CI 1.14 to 2.21; 60 eyes; 1 trial at 6 months; RR 1.54, 95% CI 1.20 to 1.97; 99 eyes; 2 trials at 12 months). We assessed the certainty of evidence for these outcomes as moderate due to small sample size. Hyphema was the most common adverse outcome (40% in the microcatheter group and 17% in the conventional trabeculotomy group), with greater likelihood of occurring in the microcatheter group (RR 2.25, 95% CI 1.25 to 4.04); the evidence was of moderate certainty due to small sample size (-1). Of the nine remaining trials, no two trials compared the same two surgical interventions: one trial compared CTT versus CTT with sclerectomy; three trials compared various suturing techniques and adjuvant use including mitomycin C, collagen implant in CTT; one trial compared CTT versus Ahmed valve implant in previously failed surgeries; one trial compared CTT with trabeculectomy; one trial compared trabeculotomy to goniotomy; and two trials compared different types of goniotomy. No trials reported quality of life or economic data. Many of the included trials had limitations in study design, implementation, and reporting, therefore the reliability and applicability of the evidence remains unclear. AUTHORS' CONCLUSIONS: The evidence suggests that there may be little to no evidence of difference between CTT and routine conventional trabeculotomy, or between viscotrabeculotomy and routine conventional trabeculotomy. A 360-degree circumferential trabeculotomy may show greater surgical success than conventional trabeculotomy. Considering the rarity of the disease, future research would benefit from a multicenter, possibly international trial, involving parents of children with PCG and with a follow-up of at least one year.
Shi C, Pundlik S, Luo G. Without low spatial frequencies, high resolution vision would be detrimental to motion perception. J Vis 2020;20(8):29.Abstract
A normally sighted person can see a grating of 30 cycles per degree or higher, but spatial frequencies needed for motion perception are much lower than that. It is unknown for natural images with a wide spectrum how all the visible spatial frequencies contribute to motion speed perception. In this work, we studied the effect of spatial frequency content on motion speed estimation for sequences of natural and stochastic pixel images by simulating different visual conditions, including normal vision, low vision (low-pass filtering), and complementary vision (high-pass filtering at the same cutoff frequencies of the corresponding low-vision conditions) conditions. Speed was computed using a biological motion energy-based computational model. In natural sequences, there was no difference in speed estimation error between normal vision and low vision conditions, but it was significantly higher for complementary vision conditions (containing only high-frequency components) at higher speeds. In stochastic sequences that had a flat frequency distribution, the error in normal vision condition was significantly larger compared with low vision conditions at high speeds. On the contrary, such a detrimental effect on speed estimation accuracy was not found for low spatial frequencies. The simulation results were consistent with the motion direction detection task performed by human observers viewing stochastic sequences. Together, these results (i) reiterate the importance of low frequencies in motion perception, and (ii) indicate that high frequencies may be detrimental for speed estimation when low frequency content is weak or not present.
Martinez-Carrasco R, Argüeso P, Fini EM. Dynasore protects ocular surface mucosal epithelia subjected to oxidative stress by maintaining UPR and calcium homeostasis. Free Radic Biol Med 2020;160:57-66.Abstract
The mucosal epithelia of the ocular surface protect against external threats to the eye. Using a model of human stratified corneal epithelial cells with mucosal differentiation, we previously demonstrated that a small molecule inhibitor of dynamin GTPases, dynasore, prevents damage to cells and their transcellular barriers when subjected to oxidative stress. Investigating mechanisms, we now report the novel finding that dynasore acts by maintaining Ca homeostasis, thereby inhibiting the PERK branch of the unfolded protein response (UPR) that promotes cell death. Dynasore was found to protect mitochondria by preventing mitochondrial permeability transition pore opening (mPTP), but, unlike reports using other systems, this was not mediated by dynamin family member DRP1. Necrostatin-1, an inhibitor of RIPK1 and lytic forms of programmed cell death, also inhibited mPTP opening and further protected the plasma membrane barrier. Significantly, necrostatin-1 did not protect the mucosal barrier. Oxidative stress increased mRNA for sXBP1, a marker of the IRE1 branch of the UPR, and CHOP, a marker of the PERK branch. It also stimulated phosphorylation of eIF2α, the upstream regulator of CHOP, as well as an increase in intracellular Ca. Dynasore selectively inhibited the increase in PERK branch markers, and also prevented the increase intracellular Ca in response to oxidative stress. The increase in PERK branch markers were also inhibited when cells were treated with the cell permeable Ca chelator, BAPTA-AM. To our knowledge, this is the first time that dynasore has been shown to have an effect on the UPR and suggests therapeutic applications.
Singh RB, Zhu S, Yung A, Dohlman TH, Dana R, Yin J. Efficacy of cyanoacrylate tissue adhesive in the management of corneal thinning and perforation due to microbial keratitis. Ocul Surf 2020;Abstract
PURPOSE: Report the efficacy of cyanoacrylate tissue adhesive (CTA) application in the management of corneal thinning and perforations associated with microbial keratitis. METHODS: A retrospective review of consecutive patients who underwent CTA application for corneal thinning and perforation secondary to microbiologically proven infectious keratitis between 2001 and 2018 at a single center. We defined successful CTA application as an intact globe without tectonic surgical intervention. RESULTS: The cohort included 67 patients, and 37 presented with corneal perforation while 30 had corneal thinning. The perforation/thinning was central/paracentral in 43 eyes and peripheral in 23 eyes. The underlying infectious etiologies were monomicrobial in 42 cases (35 bacterial, 3 fungal, 2 viral, and 2 acanthamoeba cases) and polymicrobial in 25 cases (22 polybacterial cases and 3 cases with a combination of Gram positive bacteria and fungus). The median duration of glue retention was 29 days. The CTA success rate was 73%, 64%, and 44% at 10, 30, and 180 days, respectively. CTA application appears more successful in monomicrobial (vs. polymicrobial) and Gram positive bacterial (vs. Gram negative) keratitis but the differences are statistically non-significant. The location of perforation/thinning and the use of topical corticosteroid were not associated with CTA failure. CONCLUSION: CTA was moderately effective in restoring globe integrity in severe corneal thinning and perforation secondary to microbial keratitis in the short term. However the majority of patients require tectonic surgical intervention within 6 months. CTA application success is not significantly associated with the location of thinning/perforation or the use of topical corticosteroid.
Kim S, Bispo PJM, Tanner EEL, Mitragotri S, E Silva RN, Gipson I, Chodosh J, Behlau I, Paschalis EI, Gilmore MS, Dohlman CH. The Search for Antifungal Prophylaxis After Artificial Corneal Surgery-An In Vitro Study. Cornea 2020;39(12):1547-1555.Abstract
PURPOSE: To evaluate the antifungal properties of topical antibiotics (already being used successfully to prevent bacterial endophthalmitis) and some promising antiseptics for antifungal prophylaxis in the setting of artificial corneal implantation. METHODS: Several commonly used antibiotics for antimicrobial prophylaxis after artificial corneal implantation, in addition to antiseptics [benzalkonium chloride (BAK), povidone-iodine (PI), and some ionic liquids (ILs)], were tested in vitro against Candida albicans, Fusarium solani, and Aspergillus fumigatus. The time-kill activity was determined. Toxicity was assayed in vitro on human corneal epithelial cultures using trypan blue. Adhesion and tissue invasion experiments were also carried out on porcine corneas and commonly used contact lenses, with or without gamma irradiation, and by analysis with fluorescence microscopy. RESULTS: Polymyxin B (PMB)/trimethoprim/BAK (Polytrim), PMB alone, gatifloxacin with BAK (Zymaxid), and same-concentration BAK alone exhibited antifungal activity in vitro. Moxifloxacin (MOX) or gatifloxacin without BAK-as well as trimethoprim, vancomycin, and chloramphenicol-had no effect. 1% PI and ILs had the highest efficacy/toxicity ratios (>1), and Polytrim was species dependent. Subfungicidal concentrations of Polytrim reduced adhesion of C. albicans to Kontur contact lenses. Gamma-irradiated corneas showed enhanced resistance to fungal invasion. CONCLUSIONS: Of antibiotic preparations already in use for bacterial prophylaxis after KPro surgery, Polytrim is a commonly used antibiotic with antifungal effects mediated by both PMB and BAK and may be sufficient for prophylaxis. PI as a 1% solution seems to be promising as a long-term antifungal agent. Choline-undecanoate IL is effective and virtually nontoxic and warrants further development.
Zheng Q, Jones FK, Leavitt SV, Ung L, Labrique AB, Peters DH, Lee EC, Azman AS, Azman AS. HIT-COVID, a global database tracking public health interventions to COVID-19. Sci Data 2020;7(1):286.Abstract
The COVID-19 pandemic has sparked unprecedented public health and social measures (PHSM) by national and local governments, including border restrictions, school closures, mandatory facemask use and stay at home orders. Quantifying the effectiveness of these interventions in reducing disease transmission is key to rational policy making in response to the current and future pandemics. In order to estimate the effectiveness of these interventions, detailed descriptions of their timelines, scale and scope are needed. The Health Intervention Tracking for COVID-19 (HIT-COVID) is a curated and standardized global database that catalogues the implementation and relaxation of COVID-19 related PHSM. With a team of over 200 volunteer contributors, we assembled policy timelines for a range of key PHSM aimed at reducing COVID-19 risk for the national and first administrative levels (e.g. provinces and states) globally, including details such as the degree of implementation and targeted populations. We continue to maintain and adapt this database to the changing COVID-19 landscape so it can serve as a resource for researchers and policymakers alike.
Singer MC, Marchal F, Angelos P, Bernet V, Boucai L, Buchholzer S, Burkey B, Eisele D, Erkul E, Faure F, Freitag SK, Gillespie MB, Harrell RM, Hartl D, Haymart M, Leffert J, Mandel S, Miller BS, Morris J, Pearce EN, Rahmati R, Ryan WR, Schaitkin B, Schlumberger M, Stack BC, Van Nostrand D, Wong KK, Randolph G. Salivary and lacrimal dysfunction after radioactive iodine for differentiated thyroid cancer: American Head and Neck Society Endocrine Surgery Section and Salivary Gland Section joint multidisciplinary clinical consensus statement of otolaryngology, ophth. Head Neck 2020;Abstract
BACKGROUND: Postoperative radioactive iodine (RAI) administration is widely utilized in patients with differentiated thyroid cancer. While beneficial in select patients, it is critical to recognize the potential negative sequelae of this treatment. The prevention, diagnosis, and management of the salivary and lacrimal complications of RAI exposure are addressed in this consensus statement. METHODS: A multidisciplinary panel of experts was convened under the auspices of the American Head and Neck Society Endocrine Surgery and Salivary Gland Sections. Following a comprehensive literature review to assess the current best evidence, this group developed six relevant consensus recommendations. RESULTS: Consensus recommendations on RAI were made in the areas of patient assessment, optimal utilization, complication prevention, and complication management. CONCLUSION: Salivary and lacrimal complications secondary to RAI exposure are common and need to be weighed when considering its use. The recommendations included in this statement provide direction for approaches to minimize and manage these complications.
Zucker CL, Bernstein PS, Schalek RL, Lichtman JW, Dowling JE. A connectomics approach to understanding a retinal disease. Proc Natl Acad Sci U S A 2020;117(31):18780-18787.Abstract
Macular telangiectasia type 2 (MacTel), a late-onset macular degeneration, has been linked to a loss in the retina of Müller glial cells and the amino acid serine, synthesized by the Müller cells. The disease is confined mainly to a central retinal region called the MacTel zone. We have used electron microscopic connectomics techniques, optimized for disease analysis, to study the retina from a 48-y-old woman suffering from MacTel. The major observations made were specific changes in mitochondrial structure within and outside the MacTel zone that were present in all retinal cell types. We also identified an abrupt boundary of the MacTel zone that coincides with the loss of Müller cells and macular pigment. Since Müller cells synthesize retinal serine, we propose that a deficiency of serine, required for mitochondrial maintenance, causes mitochondrial changes that underlie MacTel development.
Bengani LC, Kobashi H, Ross AE, Zhai H, Salvador-Culla B, Tulsan R, Kolovou PE, Mittal SK, Chauhan SK, Kohane DS, Ciolino JB. Steroid-eluting contact lenses for corneal and intraocular inflammation. Acta Biomater 2020;116:149-161.Abstract
Ocular inflammation is one of the leading causes of blindness worldwide, and steroids in topical ophthalmic solutions (e.g. dexamethasone eye drops) are the mainstay of therapy for ocular inflammation. For many non-infectious ocular inflammatory diseases, such as uveitis, eye drops are administered as often as once every hour. The high frequency of administration coupled with the side effects of eye drops leads to poor adherence for patients. Drug-eluting contact lenses have long been sought as a potentially superior alternative for sustained ocular drug delivery; but loading sufficient drug into contact lenses and control the release of the drug is still a challenge. A dexamethasone releasing contact lens (Dex-Lens) was previously developed by encapsulating a dexamethasone-polymer film within the periphery of a hydrogel-based contact lens. Here, we demonstrate safety and efficacy of the Dex-Lens in rabbit models in the treatment of anterior ocular inflammation. The Dex-Lens delivered drug for 7 days in vivo (rabbit model). In an ocular irritation study (Draize test) with Dex-Lens extracts, no adverse events were observed in normal rabbit eyes. Dex-Lenses effectively inhibited suture-induced corneal neovascularization and inflammation for 7 days and lipopolysaccharide-induced anterior uveitis for 5 days. The efficacy of Dex-Lenses was similar to that of hourly-administered dexamethasone eye drops. In the corneal neovascularization study, substantial corneal edema was observed in rabbit eyes that received no treatment and those that wore a vehicle lens as compared to rabbit eyes that wore the Dex-Lens. Throughout these studies, Dex-Lenses were well tolerated and did not exhibit signs of toxicity. Dexamethasone-eluting contact lenses may be an option for the treatment of ocular inflammation and a platform for ocular drug delivery. STATEMENT OF SIGNIFICANCE: Inflammation of the eye can happen either on the ocular surface (i.e. the cornea) or inside the eye, both of which can result in loss of vision or even blindness. Ocular inflammation is normally treated by steroid eye drops. Depending on the type and severity of inflammation, patients may have to take drops every hour for days at a time. Such severe dosing regimen can lead to patients missing doses. Also, more than 95% drug in an eye drop never goes inside the eye. Here we present a contact lens that release a steroid (dexamethasone) for seven days at a time. It is much more efficient than eye drops and a significant improvement since once worn, the patient will avoid missing doses.
Marmamula S, Barrenkala NR, Challa R, Kumbham TR, Modepalli SB, Yellapragada R, Bhakki M, Friedman DS, Khanna RC. Falls and visual impairment among elderly residents in 'homes for the aged' in India. Sci Rep 2020;10(1):13389.Abstract
We evaluated the prevalence of falls and their association with visual impairment (VI) in elderly residents in 'homes for the aged' in Hyderabad, India. Participants aged ≥ 60 years were recruited from 41 homes, and a comprehensive eye examination was conducted. Interviews were conducted to collect personal and demographic information, systemic health status, fear of falling, depression, and history of falls in the last year. VI categories included low vision (presenting visual acuity worse than 6/18 to 3/60) and blindness (presenting visual acuity worse than 3/60). The data of 1,074 participants were analysed. The mean age was 74.4 years (standard deviation:8.7 years); 63.9% were women, 19.4% had no formal education, 28.1% were diabetic and 56.9% were hypertensive. The annual prevalence of falls was 29.1% (95% CI: 26.4-32.0). Multivariable analysis showed those with VI had significantly higher odds of falls (Odds Ratio:1.47; p = 0.043). The prevalence of falls was higher among those with VI due to uncorrected refractive errors. We found a very high prevalence of falls in elderly individuals living in 'homes for the aged' in Hyderabad, India. Addressing VI can result in fewer falls and contribute to healthy aging in India.
McKay TB, Hutcheon AEK, Guo X, Zieske JD, Karamichos D. Modeling the cornea in 3-dimensions: Current and future perspectives. Exp Eye Res 2020;197:108127.Abstract
The cornea is an avascular, transparent ocular tissue that serves as a refractive and protective structure for the eye. Over 90% of the cornea is composed of a collagenous-rich extracellular matrix within the stroma with the other 10% composed by the corneal epithelium and endothelium layers and their corresponding supporting collagen layers (e.g., Bowman's and Descemet's membranes) at the anterior and posterior cornea, respectively. Due to its prominent role in corneal structure, tissue engineering approaches to model the human cornea in vitro have focused heavily on the cellular and functional properties of the corneal stroma. In this review, we discuss model development in the context of culture dimensionality (e.g., 2-dimensional versus 3-dimensional) and expand on the optical, biomechanical, and cellular functions promoted by the culture microenvironment. We describe current methods to model the human cornea with focus on organotypic approaches, compressed collagen, bioprinting, and self-assembled stromal models. We also expand on co-culture applications with the inclusion of relevant corneal cell types, such as epithelial, stromal keratocyte or fibroblast, endothelial, and neuronal cells. Further advancements in corneal tissue model development will markedly improve our current understanding of corneal wound healing and regeneration.
Chen EM, Armstrong GW, Cox JT, Wu DM, Hoover DR, Del Priore LV, Parikh R. Association of the Affordable Care Act Medicaid Expansion with Dilated Eye Examinations among the United States Population with Diabetes. Ophthalmology 2020;127(7):920-928.Abstract
PURPOSE: To evaluate the association between Medicaid expansion and diabetic dilated eye examinations. DESIGN: A retrospective difference in differences (DiD) analysis using individual-level survey response data from January 1, 2009, to December 31, 2017. PARTICIPANTS: A total of 52 392 survey responses from 50 states and the District of Columbia between 2009 and 2017. Responders were adults aged 18 to 64 years reporting a previous diagnosis of diabetes and a household income below 138% of the US federal poverty line (FPL). METHODS: The Centers for Disease Control and Prevention's Behavioral Risk Factor Surveillance System data were used to identify survey responders who were asked about the presence of dilated eye examinations from years before and after Medicaid expansion implementation. MAIN OUTCOME MEASURES: The DiD in proportion of dilated eye examinations among diabetic persons aged 18 to 64 years with household incomes below 138% of the FPL between states that did and did not implement Medicaid expansion. RESULTS: Implementation of Medicaid expansion policies was associated with a 1.3% (95% confidence interval [CI], -3.8 to 6.4; P = 0.61), 6.3% (95% CI, 1.3-11.3; P = 0.016), 4.1% (95% CI, -0.8 to 9.0; P = 0.11), and 2.3% (95% CI, -1.6 to 6.2; P = 0.23) increase in the proportion of diabetic persons aged 18 to 64 years with incomes below 138% of the FPL receiving a dilated eye examination within the past year due to Medicaid expansion 1, 2, 3, and 4 cumulative years after expansion, respectively. CONCLUSIONS: Medicaid expansion policies were significantly associated with an increase in dilated eye examination rates within the first 2 years after implementation. However, this increase did not persist beyond this period, with nonsignificant increases 3 and 4 cumulative years after implementation. Healthcare policymakers should be aware that additional measures beyond expanding insurance coverage may be necessary to increase and sustain the rate of dilated eye examinations among diabetic populations.

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