March 2021

PURPOSE: To report a case of bilateral acute angle-closure glaucoma associated with hyponatremia in the setting of chlorthalidone use and SARS-CoV-2 infection, and to demonstrate the challenges of managing this patient given her infectious status. METHODS: This was a case report. CASE: A 65-year-old woman taking chlorthalidone for hypertension presented to the emergency room with headache, pain, and blurry vision in both eyes and was found to be in bilateral acute angle closure. On laboratory investigation, she was severely hyponatremic and also tested positive for SARS-CoV-2. B-scan ultrasound demonstrated an apparent supraciliary effusion in the right eye. Following stabilization of her intraocular pressures with medical management, she ultimately underwent cataract extraction with iridectomies and goniosynechiolysis in both eyes. CONCLUSIONS: We report a rare case of bilateral acute angle-closure glaucoma associated with hyponatremia. Chlorthalidone use and perhaps SARS-CoV-2 infection may have contributed to this electrolyte abnormality and unique clinical presentation. In addition, we discuss the challenges of managing this complex patient with active SARS-CoV-2 infection during the pandemic.

PURPOSES: To evaluate the effect of YAG laser peripheral iridotomy (LPI) on corneal endothelial cell density (ECD) and morphology in primary angle closure suspects (PACS) over 72 months. METHODS: The Zhongshan Angle Closure Prevention Trial is a single-centre randomised controlled trial. Subjects with bilateral PACS received YAG LPI prophylactic treatment in one eye randomly, while the fellow eye served as control. Central corneal ECD and morphology were assessed using non-contact specular microscopy (SP-2000P, Topcon) at baseline, 6, 18, 36, 54 and 72 months postoperatively. Mixed model analysis was conducted to compare the difference between treated and fellow eyes. RESULTS: A total of 875 participants were included, with a mean age of 59.3±5.0 years and 83.5% female. The ECD declined significantly (p<0.001) over time in both treated and fellow eyes, but the treated eyes showed more progressive cell loss with increasing time (p<0.001). The difference in ECD loss between LPI-treated and fellow eyes was not significant at each follow-up until 72 months (4.9% in LPI eyes vs 4.2% in non-LPI eyes, p=0.003). Mean cell areas increased significantly over time in both treated and fellow eyes (p<0.001), but no longitudinal change was observed for hexagonality. In LPI-treated eyes, no significant correlation was found between age, gender, ocular biometrics, intraocular pressure and laser settings with endothelium change, except for time effect (p<0.01). CONCLUSION: ECD decreases over time primarily due to ageing effect. YAG LPI does not appear to cause clinically significant corneal endothelial damage over 72 months after treatment. TRIAL REGISTRATION NUMBER: ISRCTN45213099.

BACKGROUND: Pragmatic and comparative effectiveness randomized controlled trials (RCTs) aim to be highly generalizable studies, with broad applicability and flexibility in methods. These trials also address recruitment issues by minimizing exclusions. The trials may also appeal to potential subjects because of lower risk and lower burdens of participation. We sought to examine rates of refusal and uses of waivers of informed consent in pragmatic and comparative effectiveness RCTs. METHODS: A systematic review of pragmatic and comparative effectiveness RCTs performed wholely or in part in the United States and first published in 2014 and 2017. RESULTS: 103 studies involving 105 discrete populations were included for review. Refusal data was collected for 71 RCTs. Overall, studies reported an average rate of 31.9% of potential subjects refused participation; on an individual basis, 38.4% of people asked to take part refused at some point during recruitment. 23 trials (22%) were performed, at least in part, with a waiver of informed consent, 7 (30%) of which provided any form of notice to subjects. CONCLUSIONS: Overall refusal rates for pragmatic and comparative effectiveness RCTs appear roughly the same as other types of research, with studies reporting about a third of people solicited for participation refuse. Moreover, informed consent was waived in 22% (95% Binomial exact Confidence Interval 13.9-30.5%) of the trials, and further study is needed to understand when waivers are justified and when notice should be provided.

: To determine the response to the second TNF-α inhibitor (adalimumab and infliximab) after failing the first agent in idiopathic inflammatory retinal vascular leakage.: This was a retrospective observational case series. Patients with the diagnosis of idiopathic inflammatory retinal vascular leakage who had received both infliximab and adalimumab were included in the study.: Twelve and 15 patients received adalimumab (Group one) and infliximab (Group two) as the first treatment, respectively. The remission rates between Group one (58.3%) and Group two (66.7%) were not statistically significant. ( = .4) As the second agent, adalimumab was more effective in younger patients (27.5 ± 20.6) compared to older patients (48.75 ± 10.2). ( = .03). Moreover, patients with lower vision responded marginally better to infliximab as the second treatment ( = .06).: Either TNF-α inhibitor, adalimumab and infliximab, can be employed in the treatment of the patients with idiopathic inflammatory retinal vascular leakage who fail one of these agents.

PURPOSE: To determine the incidence of and predictive factors for cataract in intermediate uveitis. DESIGN: Retrospective cohort study METHODS: Patients were identified from the Systemic Immunosuppressive Therapy for Eye Diseases (SITE) Cohort Study, in which medical records were reviewed to determine demographic and clinical data of every eye/patient at every visit at five participating United States tertiary care uveitis centers. The primary outcome was development of vision-compromising cataract as defined by a decrease in visual acuity to 20/40 or less, or requiring cataract surgery. Survival analysis assessed visually defined cataract to avoid bias due to timing of surgery vis-à-vis inflammatory status. RESULTS: Among 2,190 eyes of 1,302 patients with intermediate uveitis the cumulative incidence of cataract formation was 7.6% by one year (95% CI=6.2-9.1%), increasing to 36.6% by ten years (95% CI=31.2-41.6%). Increased cataract risk was observed in eyes with concurrent anterior uveitis causing posterior synechiae (HR=2.68, 95% CI=2.00-3.59, p<0.001), and in eyes with epiretinal membrane formation (HR=1.54, 95% CI=1.15-2.07, p=0.004). Higher dose corticosteroid therapy was associated with significantly higher incidence of cataract, especially time-updated use of topical corticosteroids ≥2 times/day or ≥4 periocular corticosteroid injections. Low dose corticosteroid medications (oral prednisone 7.5mg daily or less, or topical corticosteroid drops <2 times/day) were not associated with increased cataract risk. CONCLUSIONS: Our study found that the incidence of clinically important cataract in intermediate uveitis is moderate. The risk is higher with markers of severity, and with higher doses of corticosteroid medications, the latter being potentially modifiable.

OBJECTIVE: To identify factors that contribute to missed cataract surgery follow-up visits, with an emphasis on socioeconomic and demographic factors. METHODS: In this retrospective cohort study, patients who underwent cataract extraction by phacoemulsification at Massachusetts Eye and Ear between 1 January and 31 December 2014 were reviewed. Second eye cases, remote and international patients, patients with foreign insurance and combined cataract cases were excluded. RESULTS: A total of 1931 cases were reviewed and 1089 cases, corresponding to 3267 scheduled postoperative visits, were included. Of these visits, 157 (4.8%) were missed. Three (0.3%) postoperative day 1, 40 (3.7%) postoperative week 1 and 114 (10.5%) postoperative month 1 visits were missed. Age<30 years (adjusted OR (aOR)=8.2, 95% CI 1.9 to 35.2) and ≥90 years (aOR=5.7, 95% CI 2.0 to 15.6) compared with patients aged 70-79 years, estimated travel time of >2 hours (aOR=3.2, 95% CI 1.4 to 7.4), smokers (aOR=2.7, 95% CI 1.6 to 4.8) and complications identified up to the postoperative visit (aOR=1.4, 95% CI 1.0 to 2.1) predicted a higher rate of missed visits. Ocular comorbidities (aOR=0.7, 95% CI 0.5 to 1.0) and previous visit best-corrected visual acuity (BCVA) of 20/50-20/80 (aOR=0.4, 95% CI 0.3 to 0.7) and 20/90-20/200 (aOR=0.4, 95% CI 0.2 to 0.9), compared with BCVA at the previous visit of 20/40 or better, predicted a lower rate of missed visits. Gender, race/ethnicity, language, education, income, insurance, alcohol use and season of the year were not associated with missed visits. CONCLUSIONS: Medical factors and demographic characteristics, including patient age and distance from the hospital, are associated with missed follow-up visits in cataract surgery. Additional studies are needed to identify disparities in cataract postoperative care that are population-specific. This information can contribute to the implementation of policies and interventions for addressing them.

Angiotensin-converting enzyme 2 (ACE2) and accessory proteases (TMPRSS2 and CTSL) are needed for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cellular entry, and their expression may shed light on viral tropism and impact across the body. We assessed the cell-type-specific expression of ACE2, TMPRSS2 and CTSL across 107 single-cell RNA-sequencing studies from different tissues. ACE2, TMPRSS2 and CTSL are coexpressed in specific subsets of respiratory epithelial cells in the nasal passages, airways and alveoli, and in cells from other organs associated with coronavirus disease 2019 (COVID-19) transmission or pathology. We performed a meta-analysis of 31 lung single-cell RNA-sequencing studies with 1,320,896 cells from 377 nasal, airway and lung parenchyma samples from 228 individuals. This revealed cell-type-specific associations of age, sex and smoking with expression levels of ACE2, TMPRSS2 and CTSL. Expression of entry factors increased with age and in males, including in airway secretory cells and alveolar type 2 cells. Expression programs shared by ACE2TMPRSS2 cells in nasal, lung and gut tissues included genes that may mediate viral entry, key immune functions and epithelial-macrophage cross-talk, such as genes involved in the interleukin-6, interleukin-1, tumor necrosis factor and complement pathways. Cell-type-specific expression patterns may contribute to the pathogenesis of COVID-19, and our work highlights putative molecular pathways for therapeutic intervention.

PURPOSE: Retinoschisis (RS), rhegmatogenous retinal detachment (RRD) and combined RS retinal detachment (RSRD) may resemble clinically and pose a diagnostic challenge. This study investigates the role of the fundus autofluorescence (AF) in differentiating RS, RRD and RSRD. METHODS: Fundus AF changes of 34 eyes diagnosed with RRD, 30 eyes with RS and 12 eyes with RSRD were retrospectively analysed. Ultra-widefield AF (UW-AF) image intensities obtained with the Optomap 200Tx were interpreted as hypo-, hyper- and isoautofluorescent or a mixed pattern with hypo- and hyperautofluorescence over and at the posterior margin (PM) of RRD, RS and RSRD. RESULTS: All RS eyes revealed isoautofluorescence over the area of RS, and nine eyes (30%) showed hypoautofluorescent PM. Among RRD, acute (≤2 weeks) and chronic (>2 weeks) RRD demonstrated distinct AF characteristics. Sixty-two per cent of RRD eyes had acute RRD. From those, 16 eyes (76%) demonstrated hypoautofluorescence over the detached area and 19 (90%) eyes with hyperautofluorescent PM. Sixty-two per cent of chronic RRD eyes demonstrated isoautofluorecence over the detached area. Eight RSRD eyes (67%) revealed hyperautofluorescence in the detached area. The positive predictive value (PPV) for hypoautofluorescence over the area of subretinal fluid (SRF) in RRD was 95%. The PPV for hyperautofluorescence over the area of SRF in RSRD was 100% and for isoautofluorescence for schitic area in RSRD and RS was 76%. CONCLUSION: The UW-AF can be a useful non-invasive adjuvant tool to distinguish between RRD, RS and RSRD. Hypo- or hyperautofluorescence over the area of interest and hyperautofluorescent PM indicates the presence of SRF.

BACKGROUND: While therapeutic success of the limbal tissue or cell transplantation to treat severe cases of limbal stem cell (LSC) deficiency (LSCD) strongly depends on the percentage of LSCs within the transplanted cells, prospective LSC enrichment has been hampered by the intranuclear localization of the previously reported LSC marker p63. The recent identification of the ATP-binding cassette transporter ABCB5 as a plasma membrane-spanning marker of LSCs that are capable of restoring the cornea and the development of an antibody directed against an extracellular loop of the ABCB5 molecule stimulated us to develop a novel treatment strategy based on the utilization of in vitro expanded allogeneic ABCB5 LSCs derived from human cadaveric limbal tissue. METHODS: We developed and validated a Good Manufacturing Practice- and European Pharmacopeia-conform production and quality-control process, by which ABCB5 LSCs are derived from human corneal rims, expanded ex vivo, isolated as homogenous cell population, and manufactured as an advanced-therapy medicinal product (ATMP). This product was tested in a preclinical study program investigating the cells' engraftment potential, biodistribution behavior, and safety. RESULTS: ABCB5 LSCs were reliably expanded and manufactured as an ATMP that contains comparably high percentages of cells expressing transcription factors critical for LSC stemness maintenance (p63) and corneal epithelial differentiation (PAX6). Preclinical studies confirmed local engraftment potential of the cells and gave no signals of toxicity and tumorgenicity. These findings were sufficient for the product to be approved by the German Paul Ehrlich Institute and the U.S. Food & Drug Administration to be tested in an international multicenter phase I/IIa clinical trial (NCT03549299) to evaluate the safety and therapeutic efficacy in patients with LSCD. CONCLUSION: Building upon these data in conjunction with the previously shown cornea-restoring capacity of human ABCB5 LSCs in animal models of LSCD, we provide an advanced allogeneic LSC-based treatment strategy that shows promise for replenishment of the patient's LSC pool, recreation of a functional barrier against invading conjunctival cells and restoration of a transparent, avascular cornea.

BACKGROUND: Primary angle-closure glaucoma (PACG) is characterized by a rise in intraocular pressure (IOP) secondary to aqueous outflow obstruction, with relative pupillary block being the most common underlying mechanism. There is increasing evidence that lens extraction may relieve pupillary block and thereby improve IOP control. As such, comparing the effectiveness of lens extraction against other commonly used treatment modalities can help inform the decision-making process. OBJECTIVES: To assess the effectiveness of lens extraction compared with other interventions in the treatment of chronic PACG in people without previous acute angle-closure attacks. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, one other database, and two trials registers (December 2019). We also screened the reference lists of included studies and the Science Citation Index database. We had no date or language restrictions. SELECTION CRITERIA: We included randomized controlled trials (RCTs) comparing lens extraction with other treatment modalities for chronic PACG. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methodology. MAIN RESULTS: We identified eight RCTs with 914 eyes. We obtained data for participants meeting our inclusion criteria for these studies (PACG only, no previous acute angle-closure attacks), resulting in 513 eyes included in this review. The participants were recruited from a diverse range of countries. We were unable to conduct meta-analyses due to different follow-up periods and insufficient data. One study compared phacoemulsification with laser peripheral iridotomy (LPI) as standard care. Participants in the phacoemulsification group were less likely to experience progression of visual field loss (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.13 to 0.91; 216 eyes; moderate certainty evidence), and required fewer IOP-lowering medications (mean difference [MD] -0.70, 95% CI -0.89 to -0.51; 263 eyes; moderate certainty evidence) compared with standard care at 12 months. Moderate certainty evidence also suggested that phacoemulsification improved gonioscopic findings at 12 months or later (MD -84.93, 95% CI -131.25 to -38.61; 106 eyes). There was little to no difference in health-related quality of life measures (MD 0.04, 95% CI -0.16 to 0.24; 254 eyes; moderate certainty evidence), and visual acuity (VA) (MD 2.03 ETDRS letter, 95% CI -0.77 to 4.84; 242 eyes) at 12 months, and no observable difference in mean IOP (MD -0.03mmHg, 95% CI -2.34 to 2.32; 257 eyes; moderate certainty evidence) compared to standard care. Irreversible loss of vision was observed in one participant in the phacoemulsification group, and three participants in standard care at 36 months (moderate-certainty evidence). One study (91 eyes) compared phacoemulsification with phaco-viscogonioplasty (phaco-VGP). Low-certainty evidence suggested that fewer IOP-lowering medications were needed at 12 months with phacoemulsification (MD -0.30, 95% CI -0.55 to -0.05). Low-certainty evidence also suggested that phacoemulsification may have improved gonioscopic findings at 12 months or later compared to phaco-VGP (angle grading MD -0.60, 95% CI -0.91 to -0.29; TISA500 MD -0.03, 95% CI -0.06 to -0.01; TISA750 MD -0.03, 95% CI -0.06 to -0.01; 91 eyes). Phacoemulsification may result in little to no difference in best corrected VA at 12 months (MD -0.01 log MAR units, 95% CI -0.10 to 0.08; low certainty evidence), and the evidence is very uncertain about its effect on IOP at 12 months (MD 0.50 mmHg, 95% CI -2.64 to 3.64; very low certainty evidence). Postoperative fibrin reaction was observed in two participants in the phacoemulsification group and four in the phaco-VGP group. Three participants in the phaco-VGP group experienced hyphema. No data were available for progression of visual field loss and quality of life measurements at 12 months. Two studies compared phacoemulsification with phaco-goniosynechialysis (phaco-GSL). Low-certainty evidence suggested that there may be little to no difference in mean IOP at 12 months (MD -0.12 mmHg, 95% CI -4.72 to 4.48; 1 study, 32 eyes) between the interventions. Phacoemulsification did not reduce the number of IOP-lowering medications compared to phaco-GSL at 12 months (MD -0.38, 95% CI -1.23 to 0.47; 1 study, 32 eyes; moderate certainty evidence). Three eyes in the phaco-GSL group developed hyphemas. No data were available at 12 months for progression of visual field loss, gonioscopic findings, visual acuity, and quality of life measures. Three studies compared phacoemulsification with combined phaco-trabeculectomy, but the data were only available for one study (63 eyes). In this study, low-certainty evidence suggested that there was little to no difference between groups in mean change in IOP from baseline (MD -0.60 mmHg, 95% CI -1.99 to 0.79), number of IOP-lowering medications at 12 months (MD 0.00, 95% CI -0.42 to 0.42), and VA measured by the Snellen chart (MD -0.03, 95% CI -0.18 to 0.12). Participants in the phacoemulsification group had fewer complications (risk ratio [RR] 0.59, 95% CI 0.34 to 1.04), and the phaco-trabeculectomy group required more IOP-lowering procedures (RR 5.81, 95% CI 1.41 to 23.88), but the evidence was very uncertain. No data were available for other outcomes. AUTHORS' CONCLUSIONS: Moderate certainty evidence showed that lens extraction has an advantage over LPI in treating chronic PACG with clear crystalline lenses over three years of follow-up; ultimately, the decision for intervention should be part of a shared decision-making process between the clinician and the patient. For people with chronic PACG and visually significant cataracts, low certainty evidence suggested that combining phacoemulsification with either viscogonioplasty or goniosynechialysis does not confer any additional benefit over phacoemulsification alone. There was insufficient evidence to draw any meaningful conclusions regarding phacoemulsification versus trabeculectomy. Low certainty evidence suggested that combining phacoemulsification with trabeculectomy does not confer any additional benefit over phacoemulsification alone, and may cause more complications instead. These conclusions only apply to short- to medium-term outcomes; studies with longer follow-up periods can help assess whether these effects persist in the long term.

PURPOSE: The International Neonatal Consortium recently published a proposed retinopathy of prematurity (ROP) activity scale intended for use in clinical trials after validation. The aim of this study was to validate the ROP activity scale (ROP-ActS) in a ROP screened cohort with protocol based collected data by evaluating the ability of the ROP-Act scores to predict ROP treatment. In addition, we aimed to evaluate the scale's sensitivity characteristic of disease severity by studying association with gestational age (GA) in comparison with conventionally used ROP stage and zone. METHODS: A cohort of 535 preterm infants with 3324 ROP examinations with an end-point of ROP treatment or end of screening in Gothenburg, Sweden, was included. Median GA was 28.1 weeks, 47.5% were girls, and 74 (13.8%) infants were treated for ROP. The validation was performed by estimating probabilities for ROP treatment, and by applying logistic and linear regression. RESULTS: The original ROP-ActS was overall well-ordered with respect to ability to predict ROP treatment but could be improved by re-ordering score 3 (zone II stage 1) and 5 (zone III stage 3) based on our clinical cohort data. The modified ROP-ActS was superior to ROP stage and zone in the prediction analysis of ROP treatment. Modified ROP-ActS was more strongly related to GA than currently used ROP stage, but not zone. CONCLUSION: In the studied cohort, the modified ROP-ActS could better predict ROP treatment compared to ROP stage and zone. Retinopathy of Prematurity Activity Scale (ROP-ActS) had a superior sensitivity characteristic studied through association to GA than conventionally used ROP stage.

To describe a database of longitudinally graded telemedicine retinal images to be used as a comparator for future studies assessing grader recall bias and ability to detect typical progression (e.g. International Classification of Retinopathy of Prematurity (ICROP) stages) as well as incremental changes in retinopathy of prematurity (ROP). Cohort comprised of retinal images from 84 eyes of 42 patients who were sequentially screened for ROP over 6 consecutive weeks in a telemedicine program and then followed to vascular maturation or treatment, and then disease stabilization. De-identified retinal images across the 6 weekly exams (2520 total images) were graded by an ROP expert based on whether ROP had improved, worsened, or stayed the same compared to the prior week's images, corresponding to an overall clinical "gestalt" score. Subsequently, we examined which parameters might have influenced the examiner's ability to detect longitudinal change; images were graded by the same ROP expert by image view (central, inferior, nasal, superior, temporal) and by retinal components (vascular tortuosity, vascular dilation, stage, hemorrhage, vessel growth), again determining if each particular retinal component or ROP in each image view had improved, worsened, or stayed the same compared to the prior week's images. Agreement between gestalt scores and view, component, and component by view scores was assessed using percent agreement, absolute agreement, and Cohen's weighted kappa statistic to determine if any of the hypothesized image features correlated with the ability to predict ROP disease trajectory in patients. The central view showed substantial agreement with gestalt scores (κ = 0.63), with moderate agreement in the remaining views. Of retinal components, vascular tortuosity showed the most overall agreement with gestalt (κ = 0.42-0.61), with only slight to fair agreement for all other components. This is a well-defined ROP database graded by one expert in a real-world setting in a masked fashion that correlated with the actual (remote in time) exams and known outcomes. This provides a foundation for subsequent study of telemedicine's ability to longitudinally assess ROP disease trajectory, as well as for potential artificial intelligence approaches to retinal image grading, in order to expand patient access to timely, accurate ROP screening.

BACKGROUND: Embolic events leading to retinal ischemia or cerebral ischemia share common risk factors; however, it has been well documented that the rate of concurrent cerebral infarction is higher in patients with a history of transient ischemic attack (TIA) than in those with monocular vision loss (MVL) due to retinal ischemia. Despite the fact that emboli to the ophthalmic artery (OA) and middle cerebral artery share the internal carotid artery (ICA) as a common origin or transit for emboli, the asymmetry in their final destination has not been fully explained. We hypothesize that the anatomic location of the OA takeoff from the ICA may contribute to the differential flow of small emboli to the retinal circulation vs the cerebral circulation. METHODS: We report a retrospective, comparative, case-control study on 28 patients with retinal ischemia and 26 patients with TIA or cerebral infarction caused by embolic events. All subjects underwent either computed tomography angiography or MRA. The location of the ipsilateral OA origin off the ICA was then graded in a blinded fashion and compared between cohorts. Vascular risk factors were collected for all patients, including age, sex, hypertension, hyperlipidemia, arrhythmia, diabetes, coronary artery disease, and smoking. RESULTS: We find that in patients with retinal ischemia of embolic etiology, the ipsilateral OA takeoff from the ICA is more proximal than in patients with cerebral infarcts or TIA (P = 0.0002). We found no statistically significant differences in demographic, vascular, or systemic risk factors. CONCLUSIONS: We find that the mean anatomical location of the OA takeoff from the ICA is significantly more proximal in patients with MVL due to retinal ischemia compared with patients with TIA or cerebral ischemia. This finding contributes significantly to our understanding of a long observed but poorly understood phenomenon that patients with MVL are less likely to have concurrent cerebral ischemia than are patients with TIA.

PURPOSE: To evaluate the effects of electron-beam (E-beam) irradiation on the human cornea and the potential for E-beam sterilization of Boston keratoprosthesis (BK) devices when pre-assembled with a donor cornea prior to sterilization. METHODS: Human donor corneas and corneas pre-assembled in BK devices were immersed in recombinant human serum albumin (rHSA) media and E-beam irradiated at 25 kGy. Mechanical (tensile strength and modulus, and compression modulus), chemical, optical, structural, and degradation properties of the corneal tissue after irradiation and after 6 months of preservation were evaluated. RESULTS: The mechanical evaluation showed that E-beam irradiation enhanced the tensile and compression moduli of human donor corneas, with no impact on their tensile strength. By chemical and mechanical analysis, E-beam irradiation caused a minor degree of crosslinking between collagen fibrils. No ultrastructural changes due to E-beam irradiation were observed. E-beam irradiation slightly increased the stability of the cornea against collagenase-induced degradation and had no impact on glucose diffusion. The optical evaluation showed transparency of the cornea was maintained. E-beam irradiated corneal tissues and BK-cornea pre-assembled devices were stable for 6 months after room-temperature preservation. CONCLUSIONS: E-beam irradiation generated no detrimental effects on the corneal tissues or BK-cornea pre-assembled devices and improved native properties of the corneal tissue, enabling prolonged preservation at room temperature. The pre-assembly of BK in a donor cornea, followed by E-beam irradiation, offers the potential for an off-the-shelf, ready to implant keratoprosthesis device.

PURPOSE: To determine if metformin is associated with noninfectious uveitis (NIU). METHODS: Patients in an insurance claims database who initiated metformin (n = 359,139) or other oral anti-diabetic medications (n = 162,847) were followed for NIU development. Both cohort and case-control analyses were performed to assess differing exposure lengths using Cox and conditional logistic regression, respectively. RESULTS: The hazard ratio (HR) for incident NIU was not significantly different between the metformin and non-metformin cohorts [HR = 1.19, 95% Confidence Interval (CI): 0.92-1.54, = .19]. The case control analysis similarly showed no association between any metformin use 2 years before the outcome date and NIU [odds ratio (OR) = 0.64, 95% CI: 0.39-1.04, = .07]. However, there was a protective 20 association between cumulative metformin duration [(445-729 days) adjusted OR (aOR) = 0.49, 95% CI: 0.27-0.90, = .02] and dosage (>390,000 mg aOR = 0.44, 95% CI: 0.25-0.78, = .001) compared with no metformin use. CONCLUSIONS: Our results suggest metformin use for longer durations may be protective of NIU onset.

SIGNIFICANCE: Think Tank 2019 affirmed that the rate of infection associated with contact lenses has not changed in several decades. Also, there is a trend toward more serious infections associated with Acanthamoeba and fungi. The growing use of contact lenses in children demands our attention with surveillance and case-control studies. PURPOSE: The American Academy of Optometry (AAO) gathered researchers and key opinion leaders from around the world to discuss contact lens-associated microbial keratitis at the 2019 AAO Annual Meeting. METHODS: Experts presented within four sessions. Session 1 covered the epidemiology of microbial keratitis, pathogenesis of Pseudomonas aeruginosa, and the role of lens care systems and storage cases in corneal disease. Session 2 covered nonbacterial forms of keratitis in contact lens wearers. Session 3 covered future needs, challenges, and research questions in relation to microbial keratitis in youth and myopia control, microbiome, antimicrobial surfaces, and genetic susceptibility. Session 4 covered compliance and communication imperatives. RESULTS: The absolute rate of microbial keratitis has remained very consistent for three decades despite new technologies, and extended wear significantly increases the risk. Improved oxygen delivery afforded by silicone hydrogel lenses has not impacted the rates, and although the introduction of daily disposable lenses has minimized the risk of severe disease, there is no consistent evidence that they have altered the overall rate of microbial keratitis. Overnight orthokeratology lenses may increase the risk of microbial keratitis, especially secondary to Acanthamoeba, in children. Compliance remains a concern and a significant risk factor for disease. New insights into host microbiome and genetic susceptibility may uncover new theories. More studies such as case-control designs suited for rare diseases and registries are needed. CONCLUSIONS: The first annual AAO Think Tank acknowledged that the risk of microbial keratitis has not decreased over decades, despite innovation. Important questions and research directions remain.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 in Wuhan city, Hubei province, China. This is the third and largest coronavirus outbreak since the new millennium after SARS in 2002 and Middle East respiratory syndrome (MERS) in 2012. Over 3 million people have been infected and the COVID-19 has caused more than 217 000 deaths. A concern exists regarding the vulnerability of patients who have been treated with immunosuppressive drugs prior or during this pandemic. Would they be more susceptible to infection by the SARS-CoV-2 and how would their clinical course be altered by their immunosuppressed state? This is a question the wider medical fraternity-including ophthalmologists, rheumatologists, gastroenterologist and transplant physicians among others-must answer. The evidence from the SARS and MERS outbreak offer some degree of confidence that immunosuppression is largely safe in the current COVID-19 pandemic. Preliminary clinical experiences based on case reports, small series and observational studies show the morbidity and mortality rates in immunosuppressed patients may not differ largely from the general population. Overwhelmingly, current best practice guidelines worldwide recommended the continuation of immunosuppression treatment in patients who require them except for perhaps high-dose corticosteroid therapy and in patients with associated risk factors for severe COVID-19 disease.

PURPOSE: To report a case series of patients with treatment-resistant Acanthamoeba keratitis (AK) using oral miltefosine, often as salvage therapy. DESIGN: Descriptive, retrospective multicenter case series. METHODS: We reviewed 15 patients with AK unresponsive to therapy who were subsequently given adjuvant systemic miltefosine between 2011 and 2017. The main outcome measures were resolution of infection, final visual acuity, tolerance of miltefosine, and clinical course of disease. RESULTS: All patients were treated with biguanides and/or diamidines or azoles without resolution of disease before starting miltefosine. Eleven of 15 patients retained count fingers or better vision, and all were considered disease free at last follow-up. Eleven of 15 patients had worsening inflammation with miltefosine, with 10 of them improving with steroids. Six patients received multiple courses of miltefosine. Most tolerated oral miltefosine well, with mild gastrointestinal symptoms as the most common systemic side effect. CONCLUSIONS: Oral miltefosine is a generally well-tolerated treatment adjuvant in patients with refractory AK. The clinician should be prepared for a steroid-responsive inflammatory response frequently encountered during the treatment course.

BACKGROUND/AIMS: Vitrectomy to repair retinal detachment is often performed with either non-contact wide-angle viewing systems or wide-angle contact viewing systems. The purpose of this study is to assess whether the viewing system used is associated with any differences in surgical outcomes of vitrectomy for primary non-complex retinal detachment repair. METHODS: This is a multicenter, interventional, retrospective, comparative study. Eyes that underwent non-complex primary retinal detachment repair by either pars plana vitrectomy (PPV) alone or in combination with scleral buckle/PPV in 2015 were evaluated. The viewing system at the time of the retinal detachment repair was identified and preoperative patient characteristics, intraoperative findings and postoperative outcomes were recorded. RESULTS: A total of 2256 eyes were included in our analysis. Of those, 1893 surgeries used a non-contact viewing system, while 363 used a contact lens system. There was no statistically significant difference in single surgery anatomic success at 3 months (p=0.72), or final anatomic success (p=0.40). Average postoperative visual acuity for the contact-based cases was logMAR 0.345 (20/44 Snellen equivalent) compared with 0.475 (20/60 Snellen equivalent) for non-contact (p=0.001). After controlling for numerous confounding variables in multivariable analysis, viewing system choice was no longer statistically significant (p=0.097). CONCLUSION: There was no statistically significant difference in anatomic success achieved for primary retinal detachment repair when comparing non-contact viewing systems to contact lens systems. Postoperative visual acuity was better in the contact-based group but this was not statistically significant when confounding factors were controlled for.