Faculty Bibliography

PURPOSE/OBJECTIVE:To assess whether slit-scanning specular microscopy (CellChek C; Konan Medical) can repeatedly image the same corneal location using anatomic landmarks (posterior corneal rings and corneal undulations) and unique cells identified during imaging. METHODS:A total of 203 eyes (113 patients) with and without corneal pathology were imaged to assess the prevalence of anatomic landmarks. A subcohort of 20 healthy eyes was used to identify unique cells adjacent to anatomic landmarks. Landmarks were then used to locate the same cells on repeat imaging approximately 1 week later. Endothelial cell density (ECD), coefficient of variation, and percent hexagonality were calculated. Intraclass correlation coefficient and 95% limits of agreement were used to measure variability and reproducibility of imaging. RESULTS:Approximately 91% of eyes had either posterior corneal rings or undulations present. Undulations were more common than posterior corneal rings in both healthy and diseased corneas. Among subcohort eyes, unique cells were found adjacent to anatomic landmarks in 100% of eyes. Landmarks were used to reimage the same cells in 75% of eyes. There was minimal variation in ECD, coefficient of variation, and hexagonality; intraclass correlation coefficient and 95% confidence intervals were 0.891 [0.715-0.962], 0.612 [0.179-0.849], and 0.793 [0.499-0.925], respectively. The 95% limits of agreement for ECD was -359.9-260.98. CONCLUSIONS:Landmarks identified with slit-scanning specular microscopy allowed reliable reimaging of the same endothelial location, providing a powerful tool to better understand the role of the peripheral endothelium in health and disease.

PURPOSE/UNASSIGNED:Keratoconus (KC) is a common eye disease characterized by progressive corneal thinning and steepening. Despite multiple treatment options, there is no definitive cure for KC. Previously we identified loss and dysregulation of nuclear factor erythroid 2-related factor 2 (NRF2) mediated antioxidant functions in stromal cells and extracellular matrix (ECM) in KC. Here we used tear fluid samples and cell culture models to investigate oxidative stress in KC. METHODS/UNASSIGNED:Primary human KC and donor (DN) stromal fibroblasts were exposed to hydrogen peroxide (H2O2) to induce oxidative stress and treated with sulforaphane (SFN) for antioxidant rescue. The fibroblasts were then assessed for NRF2 activation and apoptosis by measuring TXNRD1, HMOX1, NRF2, and GPX3 expression and caspase-3/7 activity. ML385 was used to inhibit NRF2 functions in DN fibroblast cultures followed by measurements of cell death (Caspase 3/7), proliferation (BrdU and Ki-67 labeling) and ECM deposition by immunohistology. Oxidative stress was directly assessed in KC and non-KC subjects by measuring malondialdehyde (MDA) and glutathione peroxidase 3 (GPX3) levels in the tear fluid. RESULTS/UNASSIGNED:H2O2-stressed KC fibroblasts displayed increased apoptosis and suboptimal NRF2 activation, which could be rescued with SFN. Conversely, DN fibroblasts treated with ML385 elicited KC-like cellular phenotypes, including decreased antioxidant response, reduced cell growth, myofibroblastic changes and poor ECM deposition. Compared to unaffected controls, KC patient tear fluid exhibited elevated levels of GPX3 and MDA, a byproduct of lipid peroxidation. CONCLUSIONS/UNASSIGNED:NRF2-mediated anti-oxidative functions are dysregulated in KC. In the future SFN antioxidant treatments may be therapeutic in KC, while MDA and GPX3 may lead to promising biomarkers for diagnosis and severity predictions.

PURPOSE/OBJECTIVE:To report on the presentation, treatment, and visual outcome of stromal keratitis (SK) in the Zoster Eye Disease Study (ZEDS). DESIGN/METHODS:Secondary analysis of SK endpoint of randomized clinical trial. SUBJECTS/METHODS:Herpes Zoster Ophthalmicus (HZO) patients were randomized in a double-masked clinical trial of oral valacyclovir 1g daily or placebo for 1 year. They were followed prospectively every 3 months for 18 months for endpoints of SK, iritis (IR), endothelial keratitis (EK), or dendritiform epithelial keratitis (DEK). METHODS:Presentation of recurrent, new, or worsening SK was evaluated retrospectively by treatment assignment, randomization strata, and use of topical steroids. Investigators had been allowed discretionary treatment of endpoints including open label valacyclovir and topical steroids. Visual outcome and treatment with open label oral valacyclovir and topical steroids were evaluated. MAIN OUTCOME MEASURES/METHODS:Use of open label valacyclovir and topical steroid treatment of recurrent, new, or worsening SK, and visual acuity at 12 months. RESULTS:Recurrent, new, or worsening SK occurred in 105/527(20%) participants. Randomization group was not associated with this complication. Mean best corrected visual acuity at enrollment was logMAR 0.10±0.14 with no difference at 1 year, logMAR 0.13±0.2, and no difference between valacyclovir and placebo groups at enrollment or at 1 year. Among the 105 instances of SK, 79(75%) were recognized at scheduled study visits rather than at episodic visits. In only 11/105(10%) of recurrent, new, or worsening SK, did masked investigators opt to treat with open label oral antiviral. At the time of SK complication, 52/105(50%) were on topical steroid, but 47/52(90%) on topical steroids were using 1x daily or less, 21/47(45%) high potency and 26/47(55%) low potency (p=0.47). Of 48/105(47%) on no topical steroids at recurrent, new, or worsening SK, 18/48(38%) had discontinued steroids in the prior 3 months. 38/48(75%) on no topical steroids at complication SK were subsequently treated with high potency steroids 2x daily or more. Of 26/52(50%) on low potency steroids at complication SK, 23/26(88%) were treated with increase in frequency only. CONCLUSIONS:Individuals with ocular complications of HZO who develop SK generally maintain very good vision without use of oral antiviral therapy when monitored closely and SK is recognized and treated. Low potency topical steroids should be considered for treatment and ongoing suppression of SK in HZO.

MOTIVATION/BACKGROUND:Large-scale prospective cohort studies collect longitudinal biospecimens alongside time-to-event outcomes to investigate biomarker dynamics in relation to disease risk. The nested case-control (NCC) design provides a cost-effective alternative to full cohort biomarker studies while preserving statistical efficiency. Despite advances in joint modeling for longitudinal and time-to-event outcomes, few approaches address the unique challenges posed by NCC sampling, non-normally distributed biomarkers, and competing survival outcomes. RESULTS:Motivated by the TEDDY study, we propose "JM-NCC", a joint modeling framework designed for NCC studies with competing events. It integrates a generalized linear mixed-effects model for potentially non-normally distributed biomarkers with a cause-specific hazard model for competing risks. Two estimation methods are developed. fJM-NCC leverages NCC sub-cohort longitudinal biomarker data and full cohort survival and clinical metadata, while wJM-NCC uses only NCC sub-cohort data. Both simulation studies and an application to TEDDY microbiome dataset demonstrate the robustness and efficiency of the proposed methods. AVAILABILITY/BACKGROUND:Software is available at https://github.com/Zhaoyn-oss/JMNCC and archived on Zenodo at https://zenodo.org/records/18199759 (DOI: 10.5281/zenodo.18199759). SUPPLEMENTARY INFORMATION/BACKGROUND:Supplementary data are available at Bioinformatics online.

PURPOSE/OBJECTIVE:To evaluate the association between socioeconomic status (SES; represented by a patient's neighborhood area deprivation index) and structural and functional measurements of the eye at initial presentation for those who eventually underwent trabeculectomy. DESIGN/METHODS:A retrospective cohort study. PARTICIPANTS/METHODS:We identify patients who underwent a trabeculectomy and had at least 1 OCT scan and 1 visual field (VF) test before undergoing surgery. Patients of any age with either progressing glaucoma or uncontrolled intraocular pressure, or both, who underwent a trabeculectomy and were a part of the DOMAIN cohort study were included. METHODS:We use a subject's first recorded OCT scan and VF test to obtain baseline structural and functional measurements. We next use patient addresses to determine their census block, which is then matched to the corresponding proxy for SES. Univariate and multivariate regressions controlling for race, age, and gender were used to analyze the associations between SES and structural and functional measurements at baseline. MAIN OUTCOME MEASURE/METHODS:The association between SES and structural and functional measures at baseline. RESULTS:Among the 154 eyes in the study, we find that living in an area with greater deprivation is associated with worse structural (larger cup volumes [CVs], thinner retinal nerve fiber layer, and ganglion cell-inner plexiform layer) and functional (lower visual field index [VFI] and mean deviation [MD]) measures at baseline. However, these associations only remained statistically significant in the multivariate analysis for CV, VFI, and MD after controlling for a patient's race, gender, and age. In addition, when comparing those living in the best and worst neighborhoods, we find that living in the area with the highest decile level of deprivation is associated with a 6.63 dB lower MD at presentation compared to those living in areas with the least deprivation. CONCLUSIONS:Lower SES is associated with worse optic nerve damage and VF performance at presentation for eyes that eventually undergo trabeculectomy surgery. FINANCIAL DISCLOSURE(S)/BACKGROUND:Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Estimating causal effects in the presence of spillover among individuals within a social network poses challenges due to missing information. Spillover effects refer to the impact of an intervention on individuals not directly exposed themselves but connected to intervention recipients within the network. In network-based studies, outcomes may be missing due to study termination or participant dropout, termed censoring. We introduce an inverse probability censoring weighted estimator which extends the inverse probability weighted estimator for network-based observational studies to handle possible outcome censoring. We prove the consistency and asymptotic normality of the proposed estimator and derive a closed-form estimator for its asymptotic variance. Applying the inverse probability censoring weighted estimator, we assess spillover effects in a network-based study of a nonrandomized intervention with outcome censoring. A simulation study evaluates the finite-sample performance of the inverse probability censoring weighted estimator, demonstrating its effectiveness with sufficiently large sample sizes and number of connected subnetworks. We then employ the method to assess spillover effects of community alerts on self-reported human immunodeficiency virus risk behavior among people who inject drugs and their contacts in the Transmission Reduction Intervention Project (TRIP), from 2013 to 2015, Athens, Greece. Results suggest that community alerts may help reduce human immunodeficiency virus risk behavior for both the individuals who receive them and others in their network, possibly through shared information. In this study, we found that the risk of human immunodeficiency virus behavior was reduced by increasing the proportion of a participant's immediate contacts exposed to community alerts.