March 2017

Stagner AM, Jakobiec FA, Fay A. Primary orbital synovial sarcoma: A clinicopathologic review with a differential diagnosis and discussion of molecular genetics. Surv Ophthalmol 2017;62(2):227-236.Abstract

Synovial sarcoma is a soft-tissue sarcoma of the extremities developing in young adults that has rarely been reported in the orbit. Synovial sarcoma is associated with a unique translocation, resulting in an SYT-SSX fusion gene. We analyze 7 published periocular cases, together with the current one, to gain a better appreciation of the features of the tumor in this location and to compare the findings with those derived from nonophthalmic studies. An inferior orbital mass developed in a 31-year-old woman after experiencing periorbital and hemifacial pain for more than a decade. Radiographically, the mass was circumscribed and displayed coarse internal calcifications. A large but subtotal excision with histopathologic examination disclosed a primitive tumor composed of spindled and ovoid cells. Immunohistochemistry demonstrated positivity for nuclear transducin-like enhancer of split 1 and membranous CD99, typical for synovial sarcoma. Fluorescence in situ hybridization identified a (X,18) translocation in the tumor cells. The patient underwent postoperative adjuvant proton beam radiotherapy with a good response that has been maintained during 1 year of follow-up. Orbital soft-tissue tumors of all types are increasingly identified by their distinctive genetic signatures that offer more specificity than standard immunohistochemical tests.

Tsikata E, Laíns I, Gil J, Marques M, Brown K, Mesquita T, Melo P, da Luz Cachulo M, Kim IK, Vavvas D, Murta JN, Miller JB, Silva R, Miller JW, Chen TC, Husain D. Automated Brightness and Contrast Adjustment of Color Fundus Photographs for the Grading of Age-Related Macular Degeneration. Transl Vis Sci Technol 2017;6(2):3.Abstract

PURPOSE: The purpose of this study was to develop an algorithm to automatically standardize the brightness, contrast, and color balance of digital color fundus photographs used to grade AMD and to validate this algorithm by determining the effects of the standardization on image quality and disease grading. METHODS: Seven-field color photographs of patients (>50 years) with any stage of AMD and a control group were acquired at two study sites, with either the Topcon TRC-50DX or Zeiss FF-450 Plus cameras. Field 2 photographs were analyzed. Pixel brightness values in the red, green, and blue (RGB) color channels were adjusted in custom-built software to make the mean brightness and contrast of the images equal to optimal values determined by the Age-Related Eye Disease Study (AREDS) 2 group. RESULTS: Color photographs of 370 eyes were analyzed. We found a wide range of brightness and contrast values in the images at baseline, even for those taken with the same camera. After processing, image brightness variability (brightest image-dimmest image in a color channel) was reduced 69-fold, 62-fold, and 96-fold for the RGB channels. Contrast variability was reduced 6-fold, 8-fold, and 13-fold, respectively, after adjustment. Of the 23% images considered nongradable before adjustment, only 5.7% remained nongradable. CONCLUSIONS: This automated software enables rapid and accurate standardization of color photographs for AMD grading. TRANSLATIONAL RELEVANCE: This work offers the potential to be the future of assessing and grading AMD from photos for clinical research and teleimaging.

Lindström S, Loomis S, Turman C, Huang H, Huang J, Aschard H, Chan AT, Choi H, Cornelis M, Curhan G, De Vivo I, Eliassen HA, Fuchs C, Gaziano M, Hankinson SE, Hu F, Jensen M, Kang JH, Kabrhel C, Liang L, Pasquale LR, Rimm E, Stampfer MJ, Tamimi RM, Tworoger SS, Wiggs JL, Hunter DJ, Kraft P. A comprehensive survey of genetic variation in 20,691 subjects from four large cohorts. PLoS One 2017;12(3):e0173997.Abstract

The Nurses' Health Study (NHS), Nurses' Health Study II (NHSII), Health Professionals Follow Up Study (HPFS) and the Physicians Health Study (PHS) have collected detailed longitudinal data on multiple exposures and traits for approximately 310,000 study participants over the last 35 years. Over 160,000 study participants across the cohorts have donated a DNA sample and to date, 20,691 subjects have been genotyped as part of genome-wide association studies (GWAS) of twelve primary outcomes. However, these studies utilized six different GWAS arrays making it difficult to conduct analyses of secondary phenotypes or share controls across studies. To allow for secondary analyses of these data, we have created three new datasets merged by platform family and performed imputation using a common reference panel, the 1,000 Genomes Phase I release. Here, we describe the methodology behind the data merging and imputation and present imputation quality statistics and association results from two GWAS of secondary phenotypes (body mass index (BMI) and venous thromboembolism (VTE)). We observed the strongest BMI association for the FTO SNP rs55872725 (β = 0.45, p = 3.48x10-22), and using a significance level of p = 0.05, we replicated 19 out of 32 known BMI SNPs. For VTE, we observed the strongest association for the rs2040445 SNP (OR = 2.17, 95% CI: 1.79-2.63, p = 2.70x10-15), located downstream of F5 and also observed significant associations for the known ABO and F11 regions. This pooled resource can be used to maximize power in GWAS of phenotypes collected across the cohorts and for studying gene-environment interactions as well as rare phenotypes and genotypes.

Schuerch K, Woods RL, Lee W, Duncker T, Delori FC, Allikmets R, Tsang SH, Sparrow JR. Quantifying Fundus Autofluorescence in Patients With Retinitis Pigmentosa. Invest Ophthalmol Vis Sci 2017;58(3):1843-1855.Abstract

Purpose: Using quantitative fundus autofluorescence (qAF), we analyzed short-wavelength autofluorescent (SW-AF) rings in RP. Methods: Short-wavelength autofluorescent images (486 nm excitation) of 40 patients with RP (69 eyes) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference. Mean qAF was measured in eight preset segments (qAF8) and in region of interest (ROI)-qAF (200-700 μm) within and external to the borders of the rings at superior, temporal, and inferior sites relative to the ring. For both groups, qAF in patients with RP was compared to age-similar and race/ethnicity-matched healthy eyes at equivalent retinal locations. Results: In 71% of eyes of RP patients, qAF8 acquired internal to the inner border of the ring, was within the 95% confidence interval (CI) for healthy eyes, while in the remaining RP eyes qAF8 was either higher or lower than the CI. Measured external to the ring, qAF8 values were within the CI in 47% of RP eyes with the other eyes being higher or lower. In 28% of sites measured by ROI-qAF within the SW-AF ring, values were above the 95% CI of healthy controls. Region of interest-qAF measured just external to the ring was within the CI of healthy eyes in 74% of locations. The average local elevation in qAF within the ring was approximately 15%. In SD-OCT scans, photoreceptor-attributable reflectivity bands were thinned within and external to the ring. Conclusions: Increased fluorophore production may be a factor in the formation of the SW-AF rings in RP.

Gouveia RM, González-Andrades E, Cardona JC, González-Gallardo C, Ionescu AM, Garzon I, Alaminos M, González-Andrades M, Connon CJ. Controlling the 3D architecture of Self-Lifting Auto-generated Tissue Equivalents (SLATEs) for optimized corneal graft composition and stability. Biomaterials 2017;121:205-219.Abstract

Ideally, biomaterials designed to play specific physical and physiological roles in vivo should comprise components and microarchitectures analogous to those of the native tissues they intend to replace. For that, implantable biomaterials need to be carefully designed to have the correct structural and compositional properties, which consequently impart their bio-function. In this study, we showed that the control of such properties can be defined from the bottom-up, using smart surface templates to modulate the structure, composition, and bio-mechanics of human transplantable tissues. Using multi-functional peptide amphiphile-coated surfaces with different anisotropies, we were able to control the phenotype of corneal stromal cells and instruct them to fabricate self-lifting tissues that closely emulated the native stromal lamellae of the human cornea. The type and arrangement of the extracellular matrix comprising these corneal stromal Self-Lifting Analogous Tissue Equivalents (SLATEs) were then evaluated in detail, and was shown to correlate with tissue function. Specifically, SLATEs comprising aligned collagen fibrils were shown to be significantly thicker, denser, and more resistant to proteolytic degradation compared to SLATEs formed with randomly-oriented constituents. In addition, SLATEs were highly transparent while providing increased absorption to near-UV radiation. Importantly, corneal stromal SLATEs were capable of constituting tissues with a higher-order complexity, either by creating thicker tissues through stacking or by serving as substrate to support a fully-differentiated, stratified corneal epithelium. SLATEs were also deemed safe as implants in a rabbit corneal model, being capable of integrating with the surrounding host tissue without provoking inflammation, neo-vascularization, or any other signs of rejection after a 9-months follow-up. This work thus paves the way for the de novo bio-fabrication of easy-retrievable, scaffold-free human tissues with controlled structural, compositional, and functional properties to replace corneal, as well as other, tissues.

Chen Q, Qiu F, Zhou K, Matlock GH, Takahashi Y, Rajala RVS, Yang Y, Moran E, Ma J-X. Pathogenic Role of MicroRNA-21 in Diabetic Retinopathy Through Down-Regulation of PPARα. Diabetes 2017;Abstract

Fenofibrate, a specific agonist of peroxisome proliferator-activated receptor alpha (PPARα), displays robust therapeutic effects on diabetic retinopathy (DR) in type 2 diabetic patients. Our recent studies have shown that PPARα is down-regulated in the diabetic retina, which contributes to the pathogenesis of DR. However, the mechanism for diabetes-induced down-regulation of PPARα remains unknown. We investigated the role of microRNA-21 (miR-21) in regulating PPARα in DR. MiR-21 was over-expressed, while PPARα levels were decreased in the retina of db/db mice, a type 2 diabetic model. Such alterations were also observed in palmitate-treated retinal endothelial cells. MiR-21 targeted PPARα by inhibiting its mRNA translation. Knockout of miR-21 prevented the decrease of PPARα, alleviated microvascular damage, ameliorated inflammation and reduced cell apoptosis in the retina of db/db mice. Intravitreal injection of miR-21 inhibitor attenuated PPARα down-regulation and ameliorated retinal inflammation in db/db mice. Further, retinal miR-21 levels were increased, while PPARα levels were decreased in oxygen-induced retinopathy (OIR). Knockout of miR-21 prevented PPARα down-regulation and ameliorated retinal neovascularization and inflammation in OIR retinas. In conclusion, diabetes-induced over-expression of miR-21 in the retina is responsible, at least in part, for PPARα down-regulation in DR. Targeting miR-21 may represent a novel therapeutic strategy for DR.

Bouffard MA, Caplan LR, Torun N. Divergence Palsy due to Divalproex and Oxcarbazepine. Clin Neuropharmacol 2017;Abstract

OBJECTIVE: This case series is the first to describe divergence palsy as an adverse effect of antiepileptic drug use. Diplopia is a common adverse effect of antiepileptic drugs, but no explanatory motility deficit has ever been reported. METHODS: We present 2 patients, 1 on oxcarbazepine and 1 on divalproex, each with a normal examination result between spells and divergency palsy when symptomatic. RESULTS: Discontinuation of the antiepileptic medication led to resolution of the episodes in both cases. Rechallenge with the offending agent after washout in one patient resulted in recurrence of diplopia and divergence palsy, both resolving after subsequent withdrawal of the antiepileptic. CONCLUSIONS: Antiepileptic drugs may cause divergence palsy.

Pan B, Askew C, Galvin A, Heman-Ackah S, Asai Y, Indzhykulian AA, Jodelka FM, Hastings ML, Lentz JJ, Vandenberghe LH, Holt JR, Géléoc GS. Gene therapy restores auditory and vestibular function in a mouse model of Usher syndrome type 1c. Nat Biotechnol 2017;35(3):264-272.Abstract

Because there are currently no biological treatments for hearing loss, we sought to advance gene therapy approaches to treat genetic deafness. We focused on Usher syndrome, a devastating genetic disorder that causes blindness, balance disorders and profound deafness, and studied a knock-in mouse model, Ush1c c.216G>A, for Usher syndrome type IC (USH1C). As restoration of complex auditory and balance function is likely to require gene delivery systems that target auditory and vestibular sensory cells with high efficiency, we delivered wild-type Ush1c into the inner ear of Ush1c c.216G>A mice using a synthetic adeno-associated viral vector, Anc80L65, shown to transduce 80-90% of sensory hair cells. We demonstrate recovery of gene and protein expression, restoration of sensory cell function, rescue of complex auditory function and recovery of hearing and balance behavior to near wild-type levels. The data represent unprecedented recovery of inner ear function and suggest that biological therapies to treat deafness may be suitable for translation to humans with genetic inner ear disorders.

Landegger LD, Pan B, Askew C, Wassmer SJ, Gluck SD, Galvin A, Taylor R, Forge A, Stankovic KM, Holt JR, Vandenberghe LH. A synthetic AAV vector enables safe and efficient gene transfer to the mammalian inner ear. Nat Biotechnol 2017;35(3):280-284.Abstract

Efforts to develop gene therapies for hearing loss have been hampered by the lack of safe, efficient, and clinically relevant delivery modalities. Here we demonstrate the safety and efficiency of Anc80L65, a rationally designed synthetic vector, for transgene delivery to the mouse cochlea. Ex vivo transduction of mouse organotypic explants identified Anc80L65 from a set of other adeno-associated virus (AAV) vectors as a potent vector for the cochlear cell targets. Round window membrane injection resulted in highly efficient transduction of inner and outer hair cells in mice, a substantial improvement over conventional AAV vectors. Anc80L65 round window injection was well tolerated, as indicated by sensory cell function, hearing and vestibular function, and immunologic parameters. The ability of Anc80L65 to target outer hair cells at high rates, a requirement for restoration of complex auditory function, may enable future gene therapies for hearing and balance disorders.

Dagher Z, Gerhardinger C, Vaz J, Goodridge M, Tecilazich F, Lorenzi M. The Increased Transforming Growth Factor-β Signaling Induced by Diabetes Protects Retinal Vessels. Am J Pathol 2017;187(3):627-638.Abstract

The roles of transforming growth factor (TGF)-β in extracellular matrix production and vascular remodeling, coupled with increased TGF-β expression and signaling in diabetes, suggest TGF-β as an important contributor to the microangiopathy of diabetic retinopathy and nephropathy. To investigate whether increased TGF-β signaling could be a therapeutic target for preventing retinopathy, we used a pharmacologic approach (SM16, a selective inhibitor of the type 1 TGF-β receptor activin receptor-like kinase 5, orally active) to inhibit the increased, but not the basal, Tgf-β signaling in retinal vessels of diabetic rats. At the level of vascular gene expression, 3.5 months' diabetes induced minimal changes. Diabetes + SM16 for 3 weeks caused widespread changes in gene expression poised to enhance vascular inflammation, thrombosis, leakage, and wall instability; these changes were not observed in control rats given SM16. The synergy of diabetes and SM16 in altering gene expression was not observed in the lung. At the level of vascular network morphology, 7 months' diabetes induced no detectable changes. Diabetes + SM16 for 3 weeks caused instead distorted morphology and decreased density. Thus, in diabetes, retinal vessels become dependent on a small increase in TGF-β signaling via activin receptor-like kinase 5 to maintain early integrity. The increased TGF-β signaling may protect against rapid retinopathy progression and should not be a target of inhibitory interventions.

Torkildsen G, Abelson MB, Gomes PJ, McLaurin E, Potts SL, Mah FS. Vehicle-Controlled, Phase 2 Clinical Trial of a Sustained-Release Dexamethasone Intracanalicular Insert in a Chronic Allergen Challenge Model. J Ocul Pharmacol Ther 2017;33(2):79-90.Abstract

PURPOSE: To evaluate the efficacy and safety of a sustained-release dexamethasone intracanalicular insert (Dextenza™) in a model of allergic conjunctivitis. METHODS: This was a randomized, double-masked, vehicle-controlled, Phase 2 study. Subjects had to have a positive conjunctival allergen challenge (CAC) reaction to allergen (bilateral +2 itching and redness on 5-point, 0-4 scales) at Visit 1, and for 2 of 3 time points on subsequent visits. Subjects who met entry criteria were randomized to receive Dextenza or PV (vehicle insert). Challenges occurred over 42 days, with efficacy assessed at 14 (primary endpoint visit), 28, and 40 days postinsertion. Outcome measures included the evaluation of ocular itching, redness, tearing, chemosis, eyelid swelling, rhinorrhea, and congestion. RESULTS: Twenty-eight subjects completed the study in the Dextenza group and 31 in the vehicle group. At 14 days postinsertion, Dextenza was statistically superior to PV, with least square mean differences for ocular itching of -0.76, -0.97, and -0.87 at 3, 5, and 7 min post-CAC, and for conjunctival redness of -0.46, -0.66, and -0.68 at 7, 15, and 20 min post-CAC. Clinical significance, defined as a 1-U decrease from PV, was not met for primary efficacy. Secondary endpoints, including number of subjects reporting itching and conjunctival redness, indicated superior performance of Dextenza compared with vehicle. Eleven Dextenza-treated (35.5%) and 10 vehicle-treated (30.3%) subjects each experienced a single adverse event. CONCLUSION: This Phase 2 study demonstrated preliminary efficacy and safety data of Dextenza for treatment of allergic conjunctivitis.

Nihalani BR, VanderVeen DK. Benchmarks for outcome indicators in pediatric cataract surgery. Eye (Lond) 2017;31(3):417-421.Abstract

PurposeThe purpose of this study was to establish benchmarks for outcome indicators that may help ascertain the quality of pediatric cataract surgery with primary intraocular lens (IOL) implantation.Patients and methodsA retrospective chart review of patients older than 2 years undergoing cataract surgery with primary IOL implantation, by multiple surgeons in a tertiary-care center, from November 2005 to February 2016 was conducted. Patients with ocular comorbidities that would affect the outcomes were excluded. The outcome measures chosen were as follows: (1) final best corrected Snellen visual acuity (BCVA) in patients who had bilateral cataract surgery analyzed at the last clinic visit; (2) prediction error (PE)=expected refraction-actual refraction. Mean PE and mean absolute PE were assessed 1 month postoperatively, irrespective of age or laterality.ResultsMean age at surgery was 8.3±4.6 years and mean follow-up duration was 3.7±2.7 years. The results of outcome measures were as follows: (1) BCVA was 20/40 or better in 96% (n=124 eyes, mean patient age: 8.3±4.6 years). Remaining five eyes had amblyopia with two eyes having BCVA worse than 20/100 that did not respond to amblyopia treatment. (2) Mean PE was 0.3±1.1 D and mean absolute PE was 0.9±0.7 D. PE was within ±0.5 D in 43.0%, ±1.0 D in 66%, and ±2.0 D in 95% (n=235 eyes).ConclusionGood visual acuity after cataract surgery should be expected for children with bilateral cataracts, setting a high benchmark similar to that recommended in adult cataract surgery. Prediction error is greater in pediatric eyes than in adult eyes, setting a lower benchmark. This study establishes benchmark for outcome indicators in pediatric patients older than 2 years undergoing cataract surgery with primary IOL implantation.

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