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/OBJECTIVE:We describe a case of bilateral, multiple, branch retinal artery occlusions (BRAO) associated with carotid webs. METHODS:A thorough chart review was conducted for the patient. Relevant literature was systematically reviewed. RESULTS:Eight cases of fibromuscular dysplasia (FMD) associated with retinal artery occlusions have been reported. Two additional cases of FMD with other ocular involvement have been described. No cases of carotid webs associated with retinal artery occlusions were found. CONCLUSION/CONCLUSIONS:Carotid webs, an uncommon variant of FMD, are a recognized causative etiology of arterial, ischemic stroke. The case described here of bilateral, multifocal BRAOs represents a unique manifestation of this variant of FMD. This diagnosis should be considered in the setting of an otherwise unrevealing BRAO workup, as recognition of this association may be sight and life-saving.

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 describe atypical fundus autofluorescence (FAF) patterns in geographic atrophy (GA) secondary to age-related macular degeneration (AMD) with associated age-related choroidal atrophy (ARCA). METHODS:Multimodal imaging of two cases using (pseudo-)color fundus photography, optical coherence tomography (OCT), fluorescein and indocyanine green angiography, and FAF employed with blue- and green excitation wavelengths on several devices (Spectralis, Heidelberg and (ultra-)widefield [UWF] FAF [California, Optos and EIDON, iCare]). RESULTS:Two female patients, with foveal-involving GA secondary to AMD, were assessed. All eyes demonstrated concurrent features indicative of ARCA on multimodal imaging including a paucity of choroidal vasculature, reduced choroidal pigmentation, macular pigmentary changes, peripapillary atrophy, and subretinal drusenoid deposits. Clinically, progression of GA with coalescence of lobular lesions was observed. Notably, UWF FAF with green-(California) and blue excitation wavelengths (California and EIDON) revealed atypical patterns characterized by isofluorescent FAF signals (indistinguishable from surrounding tissue) or hyperautofluorescent GA lesions. In these cases, blue excitation wavelengths were more effective than green light for delineating GA, owing to increased contrast from hypoautofluorescence related to macular pigment surrounding the lesion. CONCLUSION/CONCLUSIONS:In patients with GA and concomitant ARCA, atypical FAF patterns on UWF imaging complicate the accurate delineation and monitoring of GA. Atypical FAF patterns appear due to the properties of the confocal apertures and postprocessing features of UWF imaging that allow for the detection of scleral autofluorescence in patients with reduced choroidal vasculature, pigment and thickness. In patients with concomitant ARCA, multimodal imaging plays a crucial role in precisely identifying and tracking GA progression.

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.

PURPOSE/OBJECTIVE:To characterize the clinical and ultra-widefield (UWF) imaging of the chrysanthemum phenotype of multifocal choroiditis with panuveitis (MFCPU) and to describe a related variant, termed the miliary phenotype. DESIGN/METHODS:Multicenter, retrospective, observational case series. SUBJECTS/METHODS:Fifteen patients (20 eyes) with MFCPU exhibiting chrysanthemum lesions. METHODS:Comprehensive ophthalmic examination and multimodal imaging, including UWF color fundus photography, fundus autofluorescence, fluorescein angiography, indocyanine green angiography (ICGA), and optical coherence tomography (OCT), at baseline-first visit with both UWF-ICGA and OCT through active MFCPU lesions) and follow-up-were reviewed. Lesion morphology, topography, quadrant distribution, and choroidal vascular features such as vortex vein (VV) dilation, intervortex vein anastomoses (IVA) and choroidal vascular hyperpermeability (CVH) were analyzed. OCT was evaluated for subretinal hyperreflective material (SHRM), subfoveal choroidal thickness (SFCT), and secondary choroidal neovascularization (CNV). MAIN OUTCOME MEASURES/METHODS:Morphologic and topographic characterization of chrysanthemum and miliary lesions, prevalence of VV dilation, IVA, and CVH, complications, and visual outcomes. RESULTS:Baseline, mean age was 37.1±17.3 years; 80% were female and 73% myopic. Mean follow-up duration was 23.2±20.5 months. Disease was unilateral 67% and bilateral in 33% of patients. Lesions were predominantly peripheral, involving the mid- and far periphery in 60% of eyes and multiple quadrants in 65%. ICGA revealed VV dilation and CVH in 17/20 (85%) eyes and IVA in 15/20 (75%) eyes, colocalizing with chrysanthemum lesions. OCT showed focal (lesion-level) choroidal thickening, SHRM, and outer retinal atrophy; CNV developed in 10/20 (50%) eyes and persisted in 56% at follow-up, while subretinal fibrosis occurred in 25%. Mean SFCT decreased from 318.8±73.2 µm to 285.8±69.6 µm. Visual acuity remained stable with long-term follow-up (0.24 logMAR, 20/35). The miliary variant, identified in 4/20 (20%) eyes, presented as clusters of confluent white-yellow lesions spanning all quadrants. CONCLUSIONS:Chrysanthemum MFCPU predominantly affects the peripheral choroid and is associated with venocentric features including CVH, IVA, and VV dilation on UWF-ICGA, suggesting a potential pathogenetic role for focal choroidal congestion. The identification of a miliary variant broadens the morphologic spectrum of MFCPU. Recognition of these patterns is critical for accurate diagnosis, differentiation from other inflammatory chorioretinopathies, and prevention of CNV and fibrosis.

In a dynamic environment, sensory systems must filter out irrelevant information to construct a stable percept. Animals who rely on smell need to identify and discriminate odors despite fluctuations in concentration, yet odor receptor activation is strongly concentration dependent. Here we explored how odor signals are transformed within the mouse olfactory bulb (OB) by developing an all-optical approach to identify the connectivity between odor receptor channels (glomeruli) and the mitral and tufted cells (MTCs), while monitoring their odor responses. We found that the glomeruli and MTCs activated earliest in a sniff robustly represented odor identity across concentrations, whereas MTCs connected to later activated glomeruli were concentration dependent. Furthermore, probing the responsiveness of MTCs to glomerular input found a short temporal window of excitability at a sniff's onset, followed by prolonged odor-evoked inhibition. Our findings demonstrate, in awake animals, that the OB implements a rapid temporal filter, which is responsible for stabilizing identity across concentrations while decorrelating responses between odors.