New anti-angiogenic compound based on chemically modified heparin.

PURPOSE: The purpose of this study was to measure the anti-angiogenic effect of N-desulfated Re-N-acetylated, a chemically modified heparin (mHep). METHODS: In vitro assays (cell tube formation, viability, proliferation, and migration) with endothelial cells were performed after 24 h of treatment with mHep at 10, 100, and 1000 ng/mL or saline. In vivo tests were performed after laser-induced choroidal neovascularization (CNV) in rats, followed by an intravitreal injection (5 µL) of mHep (10, 100, 1000 ng/mL) or balanced salt solution. Immunofluorescence analysis of the CNV was performed after 14 days. RESULTS: mHep produced a statistically significant reduction in cell proliferation, tube formation, and migration, without cell viability changes when compared to saline. Mean measures of CNV area were 54.84 × 106 pixels/mm (± 12.41 × 106), 58.77 × 106 pixels/mm (± 17.52 × 106), and 59.42 × 106 pixels/mm (± 17.33 × 106) in groups 100, 1000, and 10,000 ng/mL, respectively, while in the control group, mean area was 72.23 × 106 (± 16.51 × 106). The P value was 0.0065. Perimeter analysis also demonstrated statistical significance (P = 0.0235) with the mean measure of 93.55 × 104, 94.23 × 104, and 102 × 104 in the 100 ng/mL, 1000 ng/mL, and control groups, respectively. CONCLUSIONS: These results suggest that mHep N-DRN is a potent anti-angiogenic, anti-proliferative, and anti-migratory compound with negligible anticoagulant or hemorrhagic action and no cytotoxicity for retina cells. This compound may serve as a candidate for treating choroidal neovascularization.

Altered hyaluronic acid content in tear fluid of patients with adenoviral conjunctivitis.

The adenoviral conjunctivitis is one of the biggest causes of conjunctival infection in the world. Conjunctivitis causes relatively nonspecific symptoms, as hyperaemia and chemosis. Even after biomicroscopy, complex laboratory tests, such as viral culture, are necessary to identify the pathogen or its etiology. To contribute to the better understanding of the pathobiology of the adenoviral conjunctivitis, the tear fluids of patients with unilateral acute adenovirus conjunctivitis (UAAC), normal donors (control) and patients with allergic conjunctivitis were analyzed. Tear samples were collected with Schirmer strips from control, allergic conjunctivitis and UAAC patients, diagnosed by clinical signs. UAAC tears were tested positive in viral cultures. After the elution, HA was quantified using an ELISA-like fluorometric assay and the protein profile was determined by SDS-PAGE. A profound increase in the HA tear content in UAAC patients was found when compared to control and ALC. This HA increase in UAAC tears remarkably was not observed in tears from contralateral eyes without clinical signs, nor in allergic conjunctivitis. In addition a distinct profile of UAAC tear proteins was observed in patients with UAAC. The quantification of HA in the tear fluid is a rapid, sensitive and specific test. This molecule might be a biomarker candidate for acute conjunctivitis.

Choroidal thickness in retinal pigment epithelial tear as measured by spectral domain optical coherence tomography.

PURPOSE: To evaluate the choroidal thickness with spectral domain optical coherence tomography in subjects with retinal pigment epithelial (RPE) tear compared with the choroidal thickness of their fellow eye. METHODS: For this cross-sectional investigation, seven eyes of seven patients with neovascular age-related macular degeneration and RPE tear in one eye imaged with spectral domain optical coherence tomography were identified. Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroid/sclera junction at 500 µm intervals up to 2,500 µm temporal and nasal to the fovea in both the eye with the RPE tear and the eye with intact RPE. All measurements were performed by two independent observers and averaged for the purpose of the analysis. Measurements were compared using paired t-test. RESULTS: The average age of patients was 79 years (range, 66-88 years). All subjects had dome-shaped pigment epithelial detachments before RPE tear and no dome-shaped pigment epithelial detachments in the unaffected eye. Average subfoveal choroidal thickness in the eye with the RPE tear was 154.9 ± 10.1 µm. Average subfoveal choroidal thickness in the eye with intact RPE was 212.9 ± 10.6 µm (P = 0.035). CONCLUSION: There is a significant decrease in subfoveal choroidal thickness in the subjects with RPE tear compared with their fellow eye with intact RPE. It is unclear if this thinning is a consequence of or precedes the RPE tear. Further studies are necessary to prospectively follow choroidal thickness in subjects with dome-shaped pigment epithelial detachments.

Automated Identification of Different Severity Levels of Diabetic Retinopathy Using a Handheld Fundus Camera and Single-Image Protocol.

Purpose: To evaluate the performance of artificial intelligence (AI) systems embedded in a mobile, handheld retinal camera, with a single retinal image protocol, in detecting both diabetic retinopathy (DR) and more-than-mild diabetic retinopathy (mtmDR). Design: Multicenter cross-sectional diagnostic study, conducted at 3 diabetes care and eye care facilities. Participants: A total of 327 individuals with diabetes mellitus (type 1 or type 2) underwent a retinal imaging protocol enabling expert reading and automated analysis. Methods: Participants underwent fundus photographs using a portable retinal camera (Phelcom Eyer). The captured images were automatically analyzed by deep learning algorithms retinal alteration score (RAS) and diabetic retinopathy alteration score (DRAS), consisting of convolutional neural networks trained on EyePACS data sets and fine-tuned using data sets of portable device fundus images. The ground truth was the classification of DR corresponding to adjudicated expert reading, performed by 3 certified ophthalmologists. Main Outcome Measures: Primary outcome measures included the sensitivity and specificity of the AI system in detecting DR and/or mtmDR using a single-field, macula-centered fundus photograph for each eye, compared with a rigorous clinical reference standard comprising the reading center grading of 2-field imaging protocol using the International Classification of Diabetic Retinopathy severity scale. Results: Of 327 analyzed patients (mean age, 57.0 ± 16.8 years; mean diabetes duration, 16.3 ± 9.7 years), 307 completed the study protocol. Sensitivity and specificity of the AI system were high in detecting any DR with DRAS (sensitivity, 90.48% [95% confidence interval (CI), 84.99%-94.46%]; specificity, 90.65% [95% CI, 84.54%-94.93%]) and mtmDR with the combination of RAS and DRAS (sensitivity, 90.23% [95% CI, 83.87%-94.69%]; specificity, 85.06% [95% CI, 78.88%-90.00%]). The area under the receiver operating characteristic curve was 0.95 for any DR and 0.89 for mtmDR. Conclusions: This study showed a high accuracy for the detection of DR in different levels of severity with a single retinal photo per eye in an all-in-one solution, composed of a portable retinal camera powered by AI. Such a strategy holds great potential for increasing coverage rates of screening programs, contributing to prevention of avoidable blindness. Financial Disclosures: F.K.M. is a medical consultant for Phelcom Technologies. J.A.S. is Chief Executive Officer and proprietary of Phelcom Technologies. D.L. is Chief Technology Officer and proprietary of Phelcom Technologies. P.V.P. is an employee at Phelcom Technologies.

Analysis of choroidal morphologic features and vasculature in healthy eyes using spectral-domain optical coherence tomography.

OBJECTIVE: To analyze the morphologic features and vasculature of the choroid in healthy eyes using spectral-domain (SD) optical coherence tomography (OCT). DESIGN: Cross-sectional retrospective review. PARTICIPANTS: Forty-two healthy subjects (42 eyes) with no ocular disease who underwent high-definition scanning with Cirrus high-definition OCT (Carl Zeiss Meditec, Inc., Dublin, CA) at the New England Eye Center, Boston, Massachusetts, between November 2009 and September 2010. METHODS: The SD OCT images were evaluated for morphologic features of the choroid, including the shape of the choroid-scleral border, location of the thickest point of choroid, and regions of focal choroidal thinning. Total choroidal thickness and large choroidal vessel layer thickness were measured by 2 independent observers experienced in analyzing OCT images using the Cirrus linear measurement tool at the fovea, 750 µm nasal and temporal to the fovea. Custom software was used to calculate the ratio of choroidal stroma to the choroidal vessel lumen. MAIN OUTCOME MEASURES: Qualitative assessment of the choroidal morphologic features, quantitative analysis of choroidal vasculature, and use of novel automated software to determine the ratio of choroidal stromal area to the area of choroidal vessel lumen. RESULTS: The 42 subjects had a mean age of 51.6 years. All subjects (100%) had a so-called bowl or convex shape to the choroid-sclera junction, and the thickest point of the choroid was under the fovea in 88.0% of the subjects. The mean choroidal thickness was 256.8 ± 75.8 µm, mean thickness of the large choroidal vessel layer was 204.3 ± 65.9 µm, and that of the medium choroidal vessel layer-choriocapillaris layer was 52.9 ± 20.6 µm beneath the fovea. The ratio of large choroidal vessel layer thickness to the total choroidal thickness beneath the fovea was 0.7 ± 0.06. The software-generated ratio of choroidal stromal area to the choroidal vessel lumen area was 0.27 ± 0.08, suggesting that choroidal vessel lumen forms a greater proportion of the choroid than the choroidal stroma in healthy eyes. CONCLUSIONS: This is the first study to describe the morphologic features and vasculature of the choroid in healthy eyes from 1-line raster scans obtained using SD OCT. The method described holds promise and has immediate clinical usefulness in recognizing subtle changes in choroidal morphologic features and the role of choroidal angiopathy in various disease states that, in the future, may inform new treatment methods. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Exercise-induced acute changes in systolic blood pressure do not alter choroidal thickness as measured by a portable spectral-domain optical coherence tomography device.

PURPOSE: To measure choroidal thickness in patients manifesting an acute change in systemic arterial blood pressure using a portable spectral-domain optical coherence tomography device (iVue). METHODS: Fifteen patients (15 eyes) undergoing cardiac exercise stress testing were scanned using a portable spectral-domain optical coherence tomography system (iVue). Two scan protocols were used: cross line scan for measuring choroidal thickness and the retina map scan to measure retinal thickness. Each patient was scanned before and within 3 minutes after the stress test. Blood pressure was measured at the same time as the acquisition of the scans. Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroid-sclera junction at 500-µm intervals up to 1,000 µm temporal and nasal to the fovea. Retinal thickness was measured by an automated software. All choroidal thickness measurements were performed by two independent observers. RESULTS: Fifteen patients (15 eyes) with a mean age of 60.6 (±10.4 years) were scanned. There was a significant increase in systolic but not diastolic pressure after stress testing (P < 0.05). The mean choroidal thickness measurements showed no significant difference before and after exercise stress testing (P > 0.05). In addition, there was no significant difference in retinal thickness before and after stress testing measurements (P > 0.05). CONCLUSION: There was no change in choroidal thickness or retinal thickness, despite an acute change in the systemic systolic blood pressure induced by exercise.

Artificial intelligence in uveitis: A comprehensive review.

Uveitis is a disease complex characterized by intraocular inflammation of the uvea that is an important cause of blindness and social morbidity. With the dawn of artificial intelligence (AI) and machine learning integration in health care, their application in uveitis creates an avenue to improve screening and diagnosis. Our review identified the use of artificial intelligence in studies of uveitis and classified them as diagnosis support, finding detection, screening, and standardization of uveitis nomenclature. The overall performance of models is poor, with limited datasets and a lack of validation studies and publicly available data and codes. We conclude that AI holds great promise to assist with the diagnosis and detection of ocular findings of uveitis, but further studies and large representative datasets are needed to guarantee generalizability and fairness.

Reproducibility of choroidal thickness measurements across three spectral domain optical coherence tomography systems.

PURPOSE: To investigate the reproducibility of choroidal thickness measurements in normal subjects on 3 spectral domain optical coherence tomography (SD-OCT) instruments: Zeiss Cirrus HD-OCT (Carl Zeiss Meditec Inc., Dublin, CA), Heidelberg Spectralis (Heidelberg Engineering, Heidelberg, Germany), and Optovue RTVue (Optovue Inc., Fremont, CA). DESIGN: Cross-sectional non-interventional study. PARTICIPANTS: Images were obtained in 28 eyes of 28 healthy undilated volunteers without ocular pathology in a clinical setting. METHODS: All subjects were imaged on the fovea using Cirrus HD 1-line raster, Spectralis enhanced depth imaging (EDI), and RTVue retina-cross. MAIN OUTCOME MEASURES: The choroid was measured subfoveally, 750 µm temporal, and 750 µm nasal to the fovea. All measurements were performed by 2 independent observers. Two-way analysis of variance (ANOVA) with Bonferroni's post-test, Pearson correlation, and Bland-Altman analysis were used to compare measurements. RESULTS: The group of 28 subjects consisted of 7 men and 21 women, with an average age of 35.2 years (range, 23-64 years). A 2-way ANOVA with Bonferroni's post-test revealed no significant difference in the average subfoveal choroidal thickness (P > 0.05) among systems for any location: subfoveally, 750 µm temporal, and 750 µm nasal to the fovea. The measurements of choroidal thickness from any pair of 3 instruments (Cirrus vs. Spectralis, Cirrus vs. RTVue, Spectralis vs. RTVue) were also strongly correlated. The Pearson correlation among all 2 system pairs of the 3 systems was greater than 0.9 (P < 0.0001). The 95% limits of agreement among 4 choroidal thickness measurements were +11.21% to -13.57% (bias -1.17) between Cirrus and RTVue, +10.85% to -12.45% (bias -0.80) between Spectralis and RTVue, and +12.81% to -13.33% (bias -0.25) between Cirrus and Spectralis. CONCLUSIONS: In our population of young healthy adults with normal vision, there was good reproducibility among choroidal thickness measurements of images acquired with Cirrus, Spectralis, and RTVue. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Choroidal imaging using spectral-domain optical coherence tomography.

BACKGROUND: A structurally and functionally normal choroidal vasculature is essential for retinal function. Therefore, a precise clinical understanding of choroidal morphology should be important for understanding many retinal and choroidal diseases. METHODS: PUBMED (http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed) was used for most of the literature search for this article. The criterion for inclusion of an article in the references for this review was that it included materials about both the clinical and the basic properties of choroidal imaging using spectral-domain optical coherence tomography. RESULTS: Recent reports show successful examination and accurate measurement of choroidal thickness in normal and pathologic states using spectral-domain optical coherence tomography systems. This review focuses on the principles of the new technology that make choroidal imaging using optical coherence tomography possible and on the changes that subsequently have been documented to occur in the choroid in various diseases. Additionally, it outlines future directions in choroidal imaging. CONCLUSION: Optical coherence tomography is now proven to be an effective noninvasive tool to evaluate the choroid and to detect choroidal changes in pathologic states. Additionally, choroidal evaluation using optical coherence tomography can be used as a parameter for diagnosis and follow-up.

Choroidal thickness in patients with diabetic retinopathy analyzed by spectral-domain optical coherence tomography.

PURPOSE: This study was designed to examine choroidal thickness in patients with diabetes using spectral-domain optical coherence tomography. METHODS: Forty-nine patients (49 eyes) with diabetes and 24 age-matched normal subjects underwent high-definition raster scanning using spectral-domain optical coherence tomography with frame enhancement software. Patients with diabetes were classified into 3 groups: 11 patients with mild or moderate nonproliferative diabetic retinopathy and no macular edema, 18 patients with nonproliferative diabetic retinopathy and diabetic macular edema, and 20 patients with treated proliferative diabetic retinopathy and no diabetic macular edema (treated proliferative diabetic retinopathy). Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroid/sclera junction at 500-µm intervals up to 2,500 µm temporal and nasal to the fovea. RESULTS: Reliable measurements of choroidal thickness were obtainable in 75.3% of eyes examined. Mean choroidal thickness showed a pattern of thinnest choroid nasally, thickening in the subfoveal region, and thinning again temporally in normal subjects and patients with diabetes. Mean subfoveal choroidal thickness was thinner in patients with diabetic macular edema (63.3 µm, 27.2%, P < 0.05) or treated proliferative diabetic retinopathy (69.6 µm, 30.0%, P < 0.01), compared with normal subjects. There was no difference between nonproliferative diabetic retinopathy and normal subjects. CONCLUSION: Choroidal thickness is altered in diabetes and may be related to the severity of retinopathy. Presence of diabetic macular edema is associated with a significant decrease in the choroidal thickness.

Toxicity and retinal penetration of infliximab in primates.

PURPOSE: To evaluate the retinal penetration and toxicity of two doses of intravitreal infliximab in primates. METHODS: Ten marmosets (Callithrix jacchus) were given intravitreal injection of 100 µg or 400 µg of infliximab, and balanced salt solution served as control. At baseline and after 24 hours (5 animals) and 7 days (the other 5), the eyes were examined by electroretinography. They were then killed (at 24 hours and 7 days) and assessed by light microscopy and transmission electron microscopy for toxicity and immunohistochemistry, using a biotinylated anti-human immunoglobulin G, to evaluate retinal penetration. RESULTS: There was no difference over 50% of the electroretinography b-wave between baseline and the time points studied in all animals. Light and electron microscopy, and electroretinography analysis, showed no signs of toxicity in any of the animals. Strong presence of infliximab was observed in all retinal layers 7 days after intravitreal injection at both doses (100 and 400 µg). CONCLUSION: Infliximab at doses of 100 and 400 µg seemed to cause no damage to the retina 24 hours and 7 days after its intravitreal injection, and deeply penetrated all its layers, in primates. These results encourage future perspectives for the treatment of chronic inflammatory diseases of the retina in humans.

Age-related macular degeneration: a review of current therapies and new treatments.

Age-related macular degeneration is the leading cause of vision loss in elderly individuals, as well as a medical and socio-economic challenge. The treatment of dry age-related macular degeneration is based on vitamin supplementation. New treatment studies are focused on preventing the progression of degeneration and repopulating the atrophic macula. Recently, research on the treatment of neovascular age-related macular degeneration experienced a breakthrough with the advent of anti-vascular endothelial growth factor inhibitors. Nevertheless, despite the fact that ranibizumab, aflibercept, and bevacizumab are effective in reducing severe visual impairment, patients usually lose some vision over time. Therefore, the search for new therapies and diagnostic methods is fundamentally important. Current studies are focused on new anti-vascular endothelial growth factor drugs, nucleoside reverse transcriptase inhibitors, antibody against sphingosine-1-phosphate, anti-platelet-derived growth factor, gene therapy, and RNA interference. The results of ongoing clinical studies may improve the therapy of age-related macular degeneration.

Repeatability and Reproducibility of Photoreceptor Density Measurement in the Macula Using the Spectralis High Magnification Module.

PURPOSE: To evaluate the repeatability and reproducibility of photoreceptor density assessment with manual cell counting in healthy participants imaged with the Heidelberg Spectralis High Magnification Module (HMM). DESIGN: Precision study, evaluation of diagnostic test or technology. PARTICIPANTS: Eleven eyes of 8 participants. METHODS: Images were acquired using the Spectralis HMM by a single operator during 2 separate imaging sessions. The 3 highest-quality images of each eye from each session were selected for analysis and coregistered. For a subset of participants, a second operator acquired images in 1 session, and images with the best quality were selected for analysis. Photoreceptor densities were obtained by manual counts in squares of 0.0625 mm2 located in the parafovea. Repeatability (intragrader and intrasession) and reproducibility (interoperator, intergrader, and intersession) were assessed by calculating the intraclass correlation coefficient (ICC) from linear mixed effects models. Bland-Altman plots, coefficients of repeatability, and Pearson correlation results were reported. MAIN OUTCOME MEASURES: Intragrader, intrasession, intersession, interoperator, and intergrader ICC estimates and their 95% confidence intervals for photoreceptor density measurements in the parafovea. RESULTS: Twenty-four eyes of 13 healthy participants were imaged initially. Of these, 11 eyes (45.83%) of 8 participants that had at least 3 acceptable images in each session were included in this study. Mean parafoveal photoreceptor density was 14 988 cells/mm2 (standard deviation, 1403.15 cells/mm2). Intragrader ICC was 0.84 (95% confidence interval, 0.57-0.95), intrasession ICC was 0.69 (95% confidence interval, 0.17-0.86), intersession ICC was 0.88 (95% confidence interval, 0.53-0.96), interoperator ICC was 0.70 (95% confidence interval, 0-0.95), and intergrader ICC was 0.22 (95% confidence interval, 0-0.71). CONCLUSIONS: Images obtained with the HMM allow for photoreceptor mosaic visualization in the macular area, mainly in the parafovea. Although densities obtained are in accordance with other reported methods in the literature, variability within and between images of the apparent cell mosaic were observed, and this study did not demonstrate high repeatability or reproducibility for quantitative assessments using the manual counting method.

Heparan sulfate proteoglycans: structure, protein interactions and cell signaling.

Heparan sulfate proteoglycans are ubiquitously found at the cell surface and extracellular matrix in all the animal species. This review will focus on the structural characteristics of the heparan sulfate proteoglycans related to protein interactions leading to cell signaling. The heparan sulfate chains due to their vast structural diversity are able to bind and interact with a wide variety of proteins, such as growth factors, chemokines, morphogens, extracellular matrix components, enzymes, among others. There is a specificity directing the interactions of heparan sulfates and target proteins, regarding both the fine structure of the polysaccharide chain as well precise protein motifs. Heparan sulfates play a role in cellular signaling either as receptor or co-receptor for different ligands, and the activation of downstream pathways is related to phosphorylation of different cytosolic proteins either directly or involving cytoskeleton interactions leading to gene regulation. The role of the heparan sulfate proteoglycans in cellular signaling and endocytic uptake pathways is also discussed.

Glaucoma After Corneal Trauma or Surgery-A Rapid, Inflammatory, IOP-Independent Pathway.

PURPOSE: To review clinical aspects and cellular and molecular steps in the development of long-term glaucoma after corneal surgery or acute trauma-especially the pivotal role of tumor necrosis factor alpha (TNF-α), the rapidity of the secondary damage to the retinal ganglion cells, and the clinical promise of early antiinflammatory intervention. METHODS: A series of laboratory studies on post-injury and post-surgery glaucoma have been compared to clinical outcome studies on the subject, focusing particularly on the vulnerability of the retinal ganglion cells. Alkali burn to the cornea of mice and rabbits served as the main experimental model. TNF-α titer, ganglion cell apoptosis, and depletion of optic nerve axons have been examined. Anti-TNF-α antibodies or corticosteroids have been used to protect the retinal ganglion cells. Intraocular pressure (IOP) postburn was recorded by manometric methods. RESULTS: In animals with alkali burn to the cornea, damage to the retina can occur within 24 to 72 hours. This is not because of a direct pH change posteriorly-the alkali is effectively buffered at the iris-lens level. Rather, TNF-α (and other inflammatory cytokines), generated anteriorly, rapidly diffuses posteriorly to cause apoptosis of the ganglion cells. During this time, the IOP remains much lower than the reported values required to cause ganglion cell damage. The TNF-α antibody infliximab or corticosteroids, if administered promptly, are markedly protective of the ganglion cells. CONCLUSIONS: A rapidly initiated, inflammatory (TNF-α mediated), IOP-independent pathway to glaucoma, resulting from acute anterior segment trauma or surgery, has been identified in laboratory studies. Prompt prophylactic treatment with antiinflammatory agents has been shown to be markedly neuroprotective of retinal ganglion cells, presumably capable of reducing the risk of late glaucoma.

Immunofluorescence confocal microscopy of porcine corneas following collagen cross-linking treatment with riboflavin and ultraviolet A.

PURPOSE: To assess ultrastructural stromal modifications in porcine corneas after riboflavin and ultraviolet A (UVA) exposure using immunofluorescence confocal imaging. METHODS: Twenty-five freshly enucleated porcine eyes were enrolled in the study. Five eyes served as control (group I). Twenty eyes had their epithelium removed (groups I, II, IV, and V) and five eyes had their epithelium intact (group III). Groups II and III were cross-linked with riboflavin 0.1% solution (10 mg riboflavin-5-phosphate in 10 mL 20% dextran-T-500) and exposed to UVA (365 nm, 3 mW/cm2) for 30 minutes. Group IV included five eyes soaked with riboflavin without posterior irradiation, and group V included five eyes irradiated, without previous exposure to riboflavin. Ultra-thin sections (8 microm) of the corneas were stained with anti-collagen I and DAPI and their fluorescence was revealed under confocal microscopy. RESULTS: Only the cross-linked corneas (group II) showed a pronounced, highly organized anterior fluorescence zone of 182.5 +/- 22.5 microm. Using DAPI staining, an anterior and concentrated displacement of cell nuclei due to collagen compaction was observed after crosslinking (group II). No structural changes were observed in all other groups. CONCLUSIONS: The cross-linking treatment effect can be directly visualized using confocal fluorescence imaging, allowing for a quantitative analysis. Cross-linked corneas showed a pronounced and limited anterior zone of organized collagen fibers, which was not observed in the other groups. Treatment of the cornea with riboflavin and UVA without previous deepithelialization did not induce any cross-linking effect. Consequently, to facilitate diffusion of riboflavin throughout the corneal stroma, the epithelium should be removed as an important initial step in the treatment.

Bevacizumab Injection in Patients with Neovascular Age-Related Macular Degeneration Increases Angiogenic Biomarkers.

PURPOSE: To evaluate the expression of 19 angiogenic biomarkers in the aqueous humor before and after intravitreal bevacizumab injection (IVB) in eyes with neovascular age-related macular degeneration (AMD). DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Twenty-three eyes of 23 treatment-naïve patients with choroidal neovascularization (CNV) secondary to neovascular AMD. METHODS: Eyes were diagnosed with CNV secondary to neovascular AMD and were treated with 3 monthly IVBs. Aqueous humor samples were obtained by anterior chamber paracentesis at baseline and immediately before each intravitreal bevacizumab injection. MAIN OUTCOME MEASURES: Aqueous humor levels of 19 angiogenic biomarkers (angiopoietin 2, bone morphogenetic protein 9 [BMP-9], epidermal growth factor [EGF], endoglin, endothelin 1, fibroblast growth factor [FGF]-1 and FGF-2, follistatin, granulocyte colony-stimulating factor [GCSF], heparin-binding EGF-like growth factor [HB-EGF], hepatocyte growth factor [HGF], interleukin 8, leptin, placental growth factor [PLGF], vascular endothelial growth factor [VEGF]-A, VEGF-C, VEGF-D, and tissue inhibitor of metalloproteinases [TIMP]-1 and TIMP-2) were measured. Best-corrected visual acuity (BCVA), spectral-domain OCT parameters, and intraocular pressure also were evaluated. RESULTS: Baseline aqueous VEGF-A expression was elevated in all study eyes before treatment initiation. A statistically significant decrease of VEGF-A was observed at the 1- and 2-month follow-ups. A statistically significant increased concentration was observed in 7 biomarkers: VEGF-C, angiopoietin 2, endothelin 1, follistatin, HB-EGF, HGF, and interleukin 8. The other 11 study biomarker levels (VEGF-D, BMP-9, EGF, endoglin, FGF-1, FGF-2, GCSF, leptin, PLGF, TIMP-1, and TIMP-2) did not show any significant difference during follow-up. The BCVA statistically improved significantly at 2 months. Spectral-domain OCT parameters improved significantly at all follow-ups. Mean intraocular pressure values were not statistically different during the study period. CONCLUSIONS: Despite a decrease in VEGF-A, the aqueous levels of VEGF-C, angiopoietin 2, endothelin 1, follistatin, HB-EGF, HGF, and interleukin 8 increased significantly after intravitreal injection of bevacizumab. These upregulated angiogenic biomarkers may represent new therapeutic targets in exudative AMD.

Chemical Burns of the Eye: The Role of Retinal Injury and New Therapeutic Possibilities.

PURPOSE: To propose a new treatment paradigm for chemical burns to the eye - in the acute and chronic phases. METHODS: Recent laboratory and clinical data on the biology and treatment of chemical burns are analyzed. RESULTS: Corneal blindness from chemical burns can now be successfully treated with a keratoprosthesis, on immediate and intermediate bases. Long term outcomes, however, are hampered by early retinal damage causing glaucoma. New data suggest that rapid diffusion of inflammatory cytokines posteriorly (TNF-α, etc) can severely damage the ganglion cells. Prompt anti-TNF-α treatment is markedly neuroprotective. Long term profound reduction of the intraocular pressure is also vital. CONCLUSION: A new regimen, in addition to standard treatment, for severe chemical burns is proposed. This involves tumor necrosis factor alpha (TNF-α) inhibition promptly after the accident (primarily for retinal neuroprotection), prophylactic maximal lowering of the intraocular pressure (starting immediately), and keratoprosthesis implantation in a later quiet state.

Retinal and choroidal angiogenesis: a review of new targets.

Retinal and choroidal neovascularization are a major cause of significant visual impairment, worldwide. Understanding the various factors involved in the accompanying physiopathology is vital for development of novel treatments, and most important, for preserving patient vision. The intraocular use of anti-vascular endothelial growth factor therapeutics has improved management of the retinal and choroidal neovascularization but some patients do not respond, suggesting other vascular mediators may also contribute to ocular angiogenesis. Several recent studies examined possible new targets for future anti-angiogenic therapies. Potential targets of retinal and choroidal neovascularization therapy include members of the platelet-derived growth factor family, vascular endothelial growth factor sub-family, epidermal growth factor family, fibroblast growth factor family, transforming growth factor-ß superfamily (TGF-ß1, activins, follistatin and bone morphogenetic proteins), angiopoietin-like family, galectins family, integrin superfamily, as well as pigment epithelium derived factor, hepatocyte growth factor, angiopoietins, endothelins, hypoxia-inducible factors, insulin-like growth factors, cytokines, matrix metalloproteinases and their inhibitors and glycosylation proteins. This review highlights current antiangiogenic therapies under development, and discusses future retinal and choroidal pro- and anti-angiogenic targets as wells as the importance of developing of new drugs.