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Sample records for oxygen induced retinopathy

  1. Protein Kinase B (Akt) Promotes Pathological Angiogenesis in Murine Model of Oxygen-Induced Retinopathy

    International Nuclear Information System (INIS)

    Wang, Peng; Tian, Xiao-Feng; Rong, Jun-Bo; Liu, Dan; Yi, Guo-Guo; Tan, Qian

    2011-01-01

    Akt, or protein kinase B, is an important signaling molecule that modulates many cellular processes such as cell growth, survival, and metabolism. However, the vivo roles and effectors of Akt in retinal angiogenesis are not explicitly clear. We therefore detected the expression of Akt using Western blotting or RT-PCR technologies in an animal model of oxygen-induced retinopathy, and investigated the effects of recombinant Akt on inhibiting vessels loss and Akt inhibitor on suppressing experimental retinal neovascularization in this model. We showed that in the hyperoxic phase of oxygen-induced retinopathy, the expression of Akt was greatly suppressed. In the hypoxic phase, the expression of Akt was increased dramatically. No significant differences were found in normoxic groups. Compared with control groups, administration of the recombinant Akt in the first phase of retinopathy markedly reduced capillary-free areas, while the administration of the Akt inhibitor in the second phase of retinopathy significantly decreased retinal neovascularization but capillary-free areas. These results indicate that Akt play a critical role in the pathological process (vessels loss and neovascularization) of mouse model of oxygen-induced retinopathy, which may provide a valubale therapeutic tool for ischemic-induced retinal diseases

  2. Oxygen-induced retinopathy in mice with retinal photoreceptor cell degeneration.

    Science.gov (United States)

    Zhang, Qian; Zhang, Zuo-Ming

    2014-04-25

    It is reported that retinal neovascularization seems to rarely co-exist with retinitis pigmentosa in patients and in some mouse models; however, it is not widely acknowledged as a universal phenomenon in all strains of all animal species. We aimed to further explore this phenomenon with an oxygen-induced retinopathy model in mice with retinal photoreceptor cell degeneration. Oxygen-induced retinopathy of colored and albino mice with rapid retinal degeneration were compared to homologous wild-type mice. The retinas were analyzed using high-molecular-weight FITC-dextran stained flat-mount preparation, hematoxylin and eosin (H&E) stained cross-sections, an immunohistochemical test for vascular endothelial growth factor (VEGF) distribution and Western blotting for VEGF expression after exposure to hyperoxia between postnatal days 17 (P17) and 21. Leakage and areas of non-perfusion of the retinal blood vessels were alleviated in the retinal degeneration mice. The number of preretinal vascular endothelial cell nuclei in the retinal degeneration mice was smaller than that in the homologous wild-type mice after exposure to hyperoxia (Poxygen-induced retinopathy was positively correlated with the VEGF expression level. However, the VEGF expression level was lower in the retinal degeneration mice. Proliferative retinopathy occurred in mice with rapid retinal degeneration, but retinal photoreceptor cell degeneration could partially restrain the retinal neovascularization in this rapid retinal degeneration mouse model. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. The neurovascular relation in oxygen-induced retinopathy.

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    Akula, James D; Mocko, Julie A; Benador, Ilan Y; Hansen, Ronald M; Favazza, Tara L; Vyhovsky, Tanya C; Fulton, Anne B

    2008-01-01

    Longitudinal studies in rat models of retinopathy of prematurity (ROP) have demonstrated that abnormalities of retinal vasculature and function change hand-in-hand. In the developing retina, vascular and neural structures are under cooperative molecular control. In this study of rats with oxygen-induced retinopathy (OIR) models of ROP, mRNA expression of vascular endothelial growth factor (VEGF), semaphorin (Sema), and their neuropilin receptor (NRP) were examined during the course of retinopathy to evaluate their roles in the observed neurovascular congruency. Oxygen exposures designed to induce retinopathy were delivered to Sprague-Dawley rat pups (n=36) from postnatal day (P) 0 to P14 or from P7 to P14. Room-air-reared controls (n=18) were also studied. Sensitivities of the rod photoreceptors (S(rod)) and the postreceptor cells (Sm) were derived from electroretinographic (ERG) records. Arteriolar tortuosity, T(A), was derived from digital fundus images using Retinal Image multi-Scale Analysis (RISA) image analysis software. mRNA expression of VEGF(164), semaphorin IIIA (Sema3A), and neuropilin-1 (NRP-1) was evaluated by RT-PCR of retinal extracts. Tests were performed at P15-P16, P18-P19, and P25-P26. Relations among ERG, RISA, and PCR parameters were evaluated using linear regression on log transformed data. Sm was low and T(A) was high at young ages, then both resolved by P25-P26. VEGF(164) and Sema3A mRNA expression were also elevated early and decreased with age. Low Sm was significantly associated with high VEGF(164) and Sema3A expression. Low S(rod) was also significantly associated with high VEGF(164). S(rod) and Sm were both correlated with T(A). NRP-1 expression was little affected by OIR. The postreceptor retina appears to mediate the vascular abnormalities that characterize OIR. Because of the relationships revealed by these data, early treatment that targets the neural retina may mitigate the effects of ROP.

  4. Targeting VEGF in canine oxygen-induced retinopathy - a model for human retinopathy of prematurity

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    McLeod DS

    2016-05-01

    Full Text Available D Scott McLeod, Gerard A Lutty Department of Ophthalmology, Wilmer Ophthalmological Institute, Johns Hopkins Hospital, Baltimore, MD, USA Abstract: Development of the dog superficial retinal vasculature is similar to the mechanism of human retinal vasculature development; they both develop by vasculogenesis, differentiation, and assembly of vascular precursors called angioblasts. Canine oxygen-induced retinopathy (OIR was first developed by Arnall Patz in an effort to experimentally determine the effects of hyperoxia on the development of the retinal vasculature. The canine OIR model has many characteristics in common with human retinopathy of prematurity. Exposure of 1-day-old dogs to hyperoxia for 4 days causes a vaso-obliteration throughout the retina. Vasoproliferation, after the animals have returned to room air, is robust. The initial small preretinal neovascular formations anastomose to form large preretinal membranes that eventually cause tractional retinal folds. The end-stage pathology of the canine model is similar to stage IV human retinopathy of prematurity. Therefore, canine OIR is an excellent forum to evaluate the response to drugs targeting VEGF and its receptors. Evaluation of an antibody to VEGF-R2 and the VEGF-Trap demonstrated that doses should be titered down so that preretinal neovascularization is inhibited but retinal revascularization is able to proceed, vascularizing peripheral retina and preventing it from being a source of VEGF. Keywords: angioblasts, blood vessels, endothelial cells, oxygen, retinopathy, retina, vascular endothelial cell growth factor

  5. Revisiting the mouse model of oxygen-induced retinopathy

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    Kim CB

    2016-05-01

    Full Text Available Clifford B Kim,1,2 Patricia A D’Amore,2–4 Kip M Connor1,2 1Angiogenesis Laboratory, Massachusetts Eye and Ear, 2Department of Ophthalmology, Harvard Medical School, 3Schepens Eye Research Institute, Massachusetts Eye and Ear, 4Department of Pathology, Harvard Medical School, Boston, MA, USA Abstract: Abnormal blood vessel growth in the retina is a hallmark of many retinal diseases, such as retinopathy of prematurity (ROP, proliferative diabetic retinopathy, and the wet form of age-related macular degeneration. In particular, ROP has been an important health concern for physicians since the advent of routine supplemental oxygen therapy for premature neonates more than 70 years ago. Since then, researchers have explored several animal models to better understand ROP and retinal vascular development. Of these models, the mouse model of oxygen-induced retinopathy (OIR has become the most widely used, and has played a pivotal role in our understanding of retinal angiogenesis and ocular immunology, as well as in the development of groundbreaking therapeutics such as anti-vascular endothelial growth factor injections for wet age-related macular degeneration. Numerous refinements to the model have been made since its inception in the 1950s, and technological advancements have expanded the use of the model across multiple scientific fields. In this review, we explore the historical developments that have led to the mouse OIR model utilized today, essential concepts of OIR, limitations of the model, and a representative selection of key findings from OIR, with particular emphasis on current research progress. Keywords: ROP, OIR, angiogenesis

  6. Postnatal weight gain modifies severity and functional outcome of oxygen-induced proliferative retinopathy.

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    Stahl, Andreas; Chen, Jing; Sapieha, Przemyslaw; Seaward, Molly R; Krah, Nathan M; Dennison, Roberta J; Favazza, Tara; Bucher, Felicitas; Löfqvist, Chatarina; Ong, Huy; Hellström, Ann; Chemtob, Sylvain; Akula, James D; Smith, Lois E H

    2010-12-01

    In clinical studies, postnatal weight gain is strongly associated with retinopathy of prematurity (ROP). However, animal studies are needed to investigate the pathophysiological mechanisms of how postnatal weight gain affects the severity of ROP. In the present study, we identify nutritional supply as one potent parameter that affects the extent of retinopathy in mice with identical birth weights and the same genetic background. Wild-type pups with poor postnatal nutrition and poor weight gain (PWG) exhibit a remarkably prolonged phase of retinopathy compared to medium weight gain or extensive weight gain pups. A high (r(2) = 0.83) parabolic association between postnatal weight gain and oxygen-induced retinopathy severity is observed, as is a significantly prolonged phase of proliferative retinopathy in PWG pups (20 days) compared with extensive weight gain pups (6 days). The extended retinopathy is concomitant with prolonged overexpression of retinal vascular endothelial growth factor in PWG pups. Importantly, PWG pups show low serum levels of nonfasting glucose, insulin, and insulin-like growth factor-1 as well as high levels of ghrelin in the early postoxygen-induced retinopathy phase, a combination indicative of poor metabolic supply. These differences translate into visual deficits in adult PWG mice, as demonstrated by impaired bipolar and proximal neuronal function. Together, these results provide evidence for a pathophysiological correlation between poor postnatal nutritional supply, slow weight gain, prolonged retinal vascular endothelial growth factor overexpression, protracted retinopathy, and reduced final visual outcome.

  7. Targeting VEGF in canine oxygen-induced retinopathy - a model for human retinopathy of prematurity.

    Science.gov (United States)

    McLeod, D Scott; Lutty, Gerard A

    2016-01-01

    Development of the dog superficial retinal vasculature is similar to the mechanism of human retinal vasculature development; they both develop by vasculogenesis, differentiation, and assembly of vascular precursors called angioblasts. Canine oxygen-induced retinopathy (OIR) was first developed by Arnall Patz in an effort to experimentally determine the effects of hyperoxia on the development of the retinal vasculature. The canine OIR model has many characteristics in common with human retinopathy of prematurity. Exposure of 1-day-old dogs to hyperoxia for 4 days causes a vaso-obliteration throughout the retina. Vasoproliferation, after the animals have returned to room air, is robust. The initial small preretinal neovascular formations anastomose to form large preretinal membranes that eventually cause tractional retinal folds. The end-stage pathology of the canine model is similar to stage IV human retinopathy of prematurity. Therefore, canine OIR is an excellent forum to evaluate the response to drugs targeting VEGF and its receptors. Evaluation of an antibody to VEGF-R2 and the VEGF-Trap demonstrated that doses should be titered down so that preretinal neovascularization is inhibited but retinal revascularization is able to proceed, vascularizing peripheral retina and preventing it from being a source of VEGF.

  8. In Vivo Imaging of Retinal Hypoxia in a Model of Oxygen-Induced Retinopathy.

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    Uddin, Md Imam; Evans, Stephanie M; Craft, Jason R; Capozzi, Megan E; McCollum, Gary W; Yang, Rong; Marnett, Lawrence J; Uddin, Md Jashim; Jayagopal, Ashwath; Penn, John S

    2016-08-05

    Ischemia-induced hypoxia elicits retinal neovascularization and is a major component of several blinding retinopathies such as retinopathy of prematurity (ROP), diabetic retinopathy (DR) and retinal vein occlusion (RVO). Currently, noninvasive imaging techniques capable of detecting and monitoring retinal hypoxia in living systems do not exist. Such techniques would greatly clarify the role of hypoxia in experimental and human retinal neovascular pathogenesis. In this study, we developed and characterized HYPOX-4, a fluorescence-imaging probe capable of detecting retinal-hypoxia in living animals. HYPOX-4 dependent in vivo and ex vivo imaging of hypoxia was tested in a mouse model of oxygen-induced retinopathy (OIR). Predicted patterns of retinal hypoxia were imaged by HYPOX-4 dependent fluorescence activity in this animal model. In retinal cells and mouse retinal tissue, pimonidazole-adduct immunostaining confirmed the hypoxia selectivity of HYPOX-4. HYPOX-4 had no effect on retinal cell proliferation as indicated by BrdU assay and exhibited no acute toxicity in retinal tissue as indicated by TUNEL assay and electroretinography (ERG) analysis. Therefore, HYPOX-4 could potentially serve as the basis for in vivo fluorescence-based hypoxia-imaging techniques, providing a tool for investigators to understand the pathogenesis of ischemic retinopathies and for physicians to address unmet clinical needs.

  9. Anti-VEGF therapy in the management of retinopathy of prematurity: what we learn from representative animal models of oxygen-induced retinopathy

    Directory of Open Access Journals (Sweden)

    Wang H

    2016-05-01

    Full Text Available Haibo Wang Department of Ophthalmology, John A Moran Eye Center, The University of Utah, Salt Lake City, UT, USA Abstract: Retinopathy of prematurity (ROP remains a leading cause of childhood blindness, affecting infants born prematurely. ROP is characterized by the onset of delayed physiological retinal vascular development (PRVD and followed by pathologic neovascularization into the vitreous instead of the retina, called intravitreal neovascularization (IVNV. Therefore, the therapeutic strategy for treating ROP is to promote PRVD and inhibit or prevent IVNV. Vascular endothelial growth factor (VEGF plays an important role in the pathogenesis of ROP. There is a growing body of studies testing the use of anti-VEGF agents as a treatment for ROP. Intravitreal anti-VEGF treatment for ROP has potential advantages compared with laser photocoagulation, the gold standard for the treatment of severe ROP; however, intravitreal anti-VEGF treatment has been associated with reactivation of ROP and suppression of systemic VEGF that may affect body growth and organ development in preterm infants. Therefore, it is important to understand the role of VEGF in PRVD and IVNV. This review includes the current knowledge of anti-VEGF treatment for ROP from animal models of oxygen-induced retinopathy (OIR, highlighting the importance of VEGF inhibition by targeting retinal Müller cells, which inhibits IVNV and permits PRVD. The signaling events involved in mediating VEGF expression and promoting VEGF-mediated angiogenesis, including hypoxia-dependent signaling, erythropoietin/erythropoietin receptor-, oxidative stress-, beta-adrenergic receptor-, integrin-, Notch/Delta-like ligand 4- and exon guidance molecules-mediated signaling pathways, are also discussed. Keywords: vascular endothelial growth factor, retinopathy of prematurity, intravitreal neovascularization, oxygen-induced retinopathy model, physiological retinal vascular development

  10. Accelerated oxygen-induced retinopathy is a reliable model of ischemia-induced retinal neovascularization.

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    Villacampa, Pilar; Menger, Katja E; Abelleira, Laura; Ribeiro, Joana; Duran, Yanai; Smith, Alexander J; Ali, Robin R; Luhmann, Ulrich F; Bainbridge, James W B

    2017-01-01

    Retinal ischemia and pathological angiogenesis cause severe impairment of sight. Oxygen-induced retinopathy (OIR) in young mice is widely used as a model to investigate the underlying pathological mechanisms and develop therapeutic interventions. We compared directly the conventional OIR model (exposure to 75% O2 from postnatal day (P) 7 to P12) with an alternative, accelerated version (85% O2 from P8 to P11). We found that accelerated OIR induces similar pre-retinal neovascularization but greater retinal vascular regression that recovers more rapidly. The extent of retinal gliosis is similar but neuroretinal function, as measured by electroretinography, is better maintained in the accelerated model. We found no systemic or maternal morbidity in either model. Accelerated OIR offers a safe, reliable and more rapid alternative model in which pre-retinal neovascularization is similar but retinal vascular regression is greater.

  11. 670nm photobiomodulation as a novel protection against retinopathy of prematurity: evidence from oxygen induced retinopathy models.

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    Riccardo Natoli

    Full Text Available INTRODUCTION: To investigate the validity of using 670nm red light as a preventative treatment for Retinopathy of Prematurity in two animal models of oxygen-induced retinopathy (OIR. MATERIALS AND METHODS: During and post exposure to hyperoxia, C57BL/6J mice or Sprague-Dawley rats were exposed to 670 nm light for 3 minutes a day (9J/cm². Whole mounted retinas were investigated for evidence of vascular abnormalities, while sections of neural retina were used to quantify levels of cell death using the TUNEL technique. Organs were removed, weighed and independent histopathology examination performed. RESULTS: 670 nm light reduced neovascularisation, vaso-obliteration and abnormal peripheral branching patterns of retinal vessels in OIR. The neural retina was also protected against OIR by 670 nm light exposure. OIR-exposed animals had severe lung pathology, including haemorrhage and oedema, that was significantly reduced in 670 nm+OIR light-exposed animals. There were no significance differences in the organ weights of animals in the 670 nm light-exposed animals, and no adverse effects of exposure to 670 nm light were detected. DISCUSSION: Low levels of exposure to 670 nm light protects against OIR and lung damage associated with exposure to high levels of oxygen, and may prove to be a non-invasive and inexpensive preventative treatment for ROP and chronic lung disease associated with prematurity.

  12. Sirtuin1 Over-Expression Does Not Impact Retinal Vascular and Neuronal Degeneration in a Mouse Model of Oxygen-Induced Retinopathy

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    Michan, Shaday; Juan, Aimee M.; Hurst, Christian G.; Cui, Zhenghao; Evans, Lucy P.; Hatton, Colman J.; Pei, Dorothy T.; Ju, Meihua; Sinclair, David A.; Smith, Lois E. H.; Chen, Jing

    2014-01-01

    Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP) in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1), a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR), as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy. PMID:24416337

  13. Sirtuin1 over-expression does not impact retinal vascular and neuronal degeneration in a mouse model of oxygen-induced retinopathy.

    Science.gov (United States)

    Michan, Shaday; Juan, Aimee M; Hurst, Christian G; Cui, Zhenghao; Evans, Lucy P; Hatton, Colman J; Pei, Dorothy T; Ju, Meihua; Sinclair, David A; Smith, Lois E H; Chen, Jing

    2014-01-01

    Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP) in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1), a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR), as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy.

  14. Fatty acid binding protein 4 deficiency protects against oxygen-induced retinopathy in mice.

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    Magali Saint-Geniez

    Full Text Available Retinopathy of prematurity (ROP is a leading cause of blindness in children worldwide due to increasing survival rates of premature infants. Initial suppression, followed by increased production of the retinal vascular endothelial growth factor-A (VEGF expression are key events that trigger the pathological neovascularization in ROP. Fatty acid binding protein 4 (FABP4 is an intracellular lipid chaperone that is induced by VEGF in a subset of endothelial cells. FABP4 exhibits a pro-angiogenic function in cultured endothelial cells and in airway microvasculature, but whether it plays a role in modulation of retinal angiogenesis is not known. We hypothesized that FABP4 deficiency could ameliorate pathological retinal vascularization and investigated this hypothesis using a well-characterized mouse model of oxygen-induced retinopathy (OIR. We found that FABP4 was not expressed in retinal vessels, but was present in resident macrophages/microglial cells and endothelial cells of the hyaloid vasculature in the immature retina. While FABP4 expression was not required for normal development of retinal vessels, FABP4 expression was upregulated and localized to neovascular tufts in OIR. FABP4-/- mice demonstrated a significant decrease in neovessel formation as well as a significant improvement in physiological revascularization of the avascular retinal tissues. These alterations in retinal vasculature were accompanied by reduced endothelial cell proliferation, but no effect on apoptosis or macrophage/microglia recruitment. FABP4-/- OIR samples demonstrated decreased expression of genes involved in angiogenesis, such as Placental Growth Factor, and angiopoietin 2. Collectively, our findings suggest FABP4 as a potential target of pathologic retinal angiogenesis in proliferative retinopathies.

  15. Protective Role of Aldose Reductase Deletion in an Animal Model of Oxygen-Induced Retinopathy

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    Zhongjie Fu

    2011-05-01

    Full Text Available Retinopathy of prematurity (ROP is a common disease occurred in premature babies. Both vascular abnormality and neural dysfunction of the retina were reported, and oxidative stress was involved. Previously, it has been showed that deficiency of aldose reductase (AR, the rate-limiting enzyme in polyol pathway, lowered oxidative stress. Here, the effect of AR deletion on neonatal retinal injury was investigated by using a mouse model of ROP (oxygen-induced retinopathy, OIR. Seven-day-old pups were exposed to 75% oxygen for 5 days and then returned to room air. The vascular changes and neuronal/glial responses were examined and compared between wild-type and AR-deficient OIR mice. Significantly reduced vaso-obliterated area, blood vessel leakage, and early revascularization were observed in AR-deficient OIR mice. Moreover, reduced amacrine cells and less distorted strata were observed in AR-deficient OIR mice. Less astrocytic immunoreactivity and reduced Müller cell gliosis were also observed in AR-deficient mice. After OIR, nitrotyrosine immunoreactivity and poly (ADP-ribose (PAR translocation, which are two oxidative stress markers, were decreased in AR-deficient mice. Significant decrease in VEGF, pho-Erk1/2, pho-Akt, and pho-I?B expression was found in AR-deficient OIR retinae. Thus, these observations suggest that the deficiency of aldose reductase may protect the retina in the OIR model.

  16. Honokiol inhibits pathological retinal neovascularization in oxygen-induced retinopathy mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Vavilala, Divya Teja [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, MO (United States); O’Bryhim, Bliss E. [Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS (United States); Ponnaluri, V.K. Chaithanya [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, MO (United States); White, R. Sid; Radel, Jeff [Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS (United States); Symons, R.C. Andrew [Department of Ophthalmology, University of Kansas Medical Center, Kansas City, KS (United States); Ophthalmology Department, Royal Melbourne Hospital, University of Melbourne, Victoria (Australia); Department of Surgery, Royal Melbourne Hospital, University of Melbourne, Victoria (Australia); Mukherji, Mridul, E-mail: mukherjim@umkc.edu [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, MO (United States)

    2013-09-06

    Highlights: •Aberrant activation of HIF pathway is the underlying cause of ischemic neovascularization. •Honokiol has better therapeutic index as a HIF inhibitor than digoxin and doxorubicin. •Daily IP injection of honokiol in OIR mouse model reduced retinal neovascularization. •Honokiol also prevents vaso-obliteration, the characteristic feature of the OIR model. •Honokiol enhanced physiological revascularization of the retinal vascular plexuses. -- Abstract: Aberrant activation of the hypoxia inducible factor (HIF) pathway is the underlying cause of retinal neovascularization, one of the most common causes of blindness worldwide. The HIF pathway also plays critical roles during tumor angiogenesis and cancer stem cell transformation. We have recently shown that honokiol is a potent inhibitor of the HIF pathway in a number of cancer and retinal pigment epithelial cell lines. Here we evaluate the safety and efficacy of honokiol, digoxin, and doxorubicin, three recently identified HIF inhibitors from natural sources. Our studies show that honokiol has a better safety to efficacy profile as a HIF inhibitor than digoxin and doxorubicin. Further, we show for the first time that daily intraperitoneal injection of honokiol starting at postnatal day (P) 12 in an oxygen-induced retinopathy (OIR) mouse model significantly reduced retinal neovascularization at P17. Administration of honokiol also prevents the oxygen-induced central retinal vaso-obliteration, characteristic feature of the OIR model. Additionally, honokiol enhanced physiological revascularization of the retinal vascular plexuses. Since honokiol suppresses multiple pathways activated by HIF, in addition to the VEGF signaling, it may provide advantages over current treatments utilizing specific VEGF antagonists for ocular neovascular diseases and cancers.

  17. The anatomy of the rat eye with oxygen-induced retinopathy.

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    Akula, James D; Favazza, Tara L; Mocko, Julie A; Benador, Ilan Y; Asturias, Ana L; Kleinman, Michael S; Hansen, Ronald M; Fulton, Anne B

    2010-02-01

    Prior studies have documented the intertwined developmental courses of retinal blood vessel tortuosity (in fundus photographs) and retinal dysfunction (in electroretinographs) in Sprague-Dawley rat models of retinopathy of prematurity (ROP). Two such models, the "50/10 model" and the "75 model," are named after the oxygen regimens used to induce retinopathy and are characterized by distinct neurovascular courses that span a range of disease severity. In this study of 50/10 and 75 model rats, retinal flatmounts were used to study the full vasculature at postnatal day (P) 15, P19 and P30. In addition, the layers of the neural retina were measured in toluidine blue-stained cross sections. Finally, gross anatomic features of the eye, including axial length, retinal surface area, and the ratio of anterior to posterior axial-lengths were evaluated. Both clock hours of neovascularization (NV) and percent avascular retina (AR) peaked at P19 and resolved by P30. Through P19, NV was found in every 50/10 model rat, but in only 60% of 75 model rats. AR was positively related to NV. All inner layers of the retina (outer plexiform layer through ganglion cell layer) were attenuated in 50/10 model rats but, in the 75 model, no layer differed significantly from that in controls. The eyes in both ROP models were smaller than those of age-matched controls. The ratio of anterior to posterior axial-lengths ranged from 0.45 in controls through 0.37 in the 75 model to 0.32 in the 50/10 model. Thus, eye growth is altered in these rat models of ROP.

  18. Hypoxia-induced retinopathy model in adult zebrafish

    DEFF Research Database (Denmark)

    Cao, Ziquan; Jensen, Lasse D.; Rouhi, Pegah

    2010-01-01

    Hypoxia-induced vascular responses, including angiogenesis, vascular remodeling and vascular leakage, significantly contribute to the onset, development and progression of retinopathy. However, until recently there were no appropriate animal disease models recapitulating adult retinopathy available....... In this article, we describe protocols that create hypoxia-induced retinopathy in adult zebrafish. Adult fli1: EGFP zebrafish are placed in hypoxic water for 3-10 d and retinal neovascularization is analyzed using confocal microscopy. It usually takes 11 d to obtain conclusive results using the hypoxia......-induced retinopathy model in adult zebrafish. This model provides a unique opportunity to study kinetically the development of retinopathy in adult animals using noninvasive protocols and to assess therapeutic efficacy of orally active antiangiogenic drugs....

  19. The rat with oxygen-induced retinopathy is myopic with low retinal dopamine.

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    Zhang, Nan; Favazza, Tara L; Baglieri, Anna Maria; Benador, Ilan Y; Noonan, Emily R; Fulton, Anne B; Hansen, Ronald M; Iuvone, P Michael; Akula, James D

    2013-12-19

    Dopamine (DA) is a neurotransmitter implicated both in modulating neural retinal signals and in eye growth. Therefore, it may participate in the pathogenesis of the most common clinical sequelae of retinopathy of prematurity (ROP), visual dysfunction and myopia. Paradoxically, in ROP myopia the eye is usually small. The eye of the rat with oxygen-induced retinopathy (OIR) is characterized by retinal dysfunction and short axial length. There have been several investigations of the early maturation of DA in rat retina, but little at older ages, and not in the OIR rat. Therefore, DA, retinal function, and refractive state were investigated in the OIR rat. In one set of rats, the development of dopaminergic (DAergic) networks was evaluated in retinal cross-sections from rats aged 14 to 120 days using antibodies against tyrosine hydroxylase (TH, the rate-limiting enzyme in the biosynthesis of DA). In another set of rats, retinoscopy was used to evaluate spherical equivalent (SE), electoretinography (ERG) was used to evaluate retinal function, and high-pressure liquid chromatography (HPLC) was used to evaluate retinal contents of DA, its precursor levodopamine (DOPA), and its primary metabolite 3,4-dihydroxyphenylacetic acid (DOPAC). The normally rapid postnatal ramification of DAergic neurons was disrupted in OIR rats. Retinoscopy revealed that OIR rats were relatively myopic. In the same eyes, ERG confirmed retinal dysfunction in OIR. HPLC of those eyes' retinae confirmed low DA. Regression analysis indicated that DA metabolism (evaluated by the ratio of DOPAC to DA) was an important additional predictor of myopia beyond OIR. The OIR rat is the first known animal model of myopia in which the eye is smaller than normal. Dopamine may modulate, or fail to modulate, neural activity in the OIR eye, and thus contribute to this peculiar myopia.

  20. Anti-VEGF therapy in the management of retinopathy of prematurity: what we learn from representative animal models of oxygen-induced retinopathy.

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    Wang, Haibo

    2016-01-01

    Retinopathy of prematurity (ROP) remains a leading cause of childhood blindness, affecting infants born prematurely. ROP is characterized by the onset of delayed physiological retinal vascular development (PRVD) and followed by pathologic neovascularization into the vitreous instead of the retina, called intravitreal neovascularization (IVNV). Therefore, the therapeutic strategy for treating ROP is to promote PRVD and inhibit or prevent IVNV. Vascular endothelial growth factor (VEGF) plays an important role in the pathogenesis of ROP. There is a growing body of studies testing the use of anti-VEGF agents as a treatment for ROP. Intravitreal anti-VEGF treatment for ROP has potential advantages compared with laser photocoagulation, the gold standard for the treatment of severe ROP; however, intravitreal anti-VEGF treatment has been associated with reactivation of ROP and suppression of systemic VEGF that may affect body growth and organ development in preterm infants. Therefore, it is important to understand the role of VEGF in PRVD and IVNV. This review includes the current knowledge of anti-VEGF treatment for ROP from animal models of oxygen-induced retinopathy (OIR), highlighting the importance of VEGF inhibition by targeting retinal Müller cells, which inhibits IVNV and permits PRVD. The signaling events involved in mediating VEGF expression and promoting VEGF-mediated angiogenesis, including hypoxia-dependent signaling, erythropoietin/erythropoietin receptor-, oxidative stress-, beta-adrenergic receptor-, integrin-, Notch/Delta-like ligand 4- and exon guidance molecules-mediated signaling pathways, are also discussed.

  1. Retinopathy of prematurity and induced changes in arterial oxygen saturation with near infrared spectrophotometry: a retrospective cohort study

    Science.gov (United States)

    von Siebenthal, K.; Keel, M.; Dietz, V.; Fauchere, J. C.; Martin, X.; Wolf, Martin; Duc, G.; Bucher, H. U.

    1996-10-01

    Near-infrared spectrophotometry (NIRS) is a noninvasive method for measuring oxygenated and deoxygenated hemoglobin in the neonatal brain. Using oxygen as a tracer, it is possible to calculate cerebral blood flow (cbf) and hemoglobin concentration (cHbc), which corresponds to cerebral blood volume, by inducing small changes in arterial oxygen saturation. Variability of tcpO2 is considered to be associated with severe retinopathy of prematurity (ROP). A preliminary analysis without control found a 51 percent incidence of ROP in infants subjected to NIRS measurements whereas among infants who were not exposed to oxygen changes, only 29 percent developed ROP. A controlled study with matched pairs was performed. Thirty-nine premature newborns who had received NIRS recordings were matched with 39 out of 172 infants who had not received NIRS. Using this controlled study design there was no difference in the incidence and severity of ROP between the two groups. The conclusions are that: 1) small changes in oxygen saturation of 3 to 10 percent to measure cbf and cHbc did not increase the incidence or the degree of severity of ROP. 2) A controlled study design is important. Analyses of uncontrolled data would have led to the conclusion that oxygen changes as used with NIRS increase the risk of ROP.

  2. Adenosine receptors and caffeine in retinopathy of prematurity.

    Science.gov (United States)

    Chen, Jiang-Fan; Zhang, Shuya; Zhou, Rong; Lin, Zhenlang; Cai, Xiaohong; Lin, Jing; Huo, Yuqing; Liu, Xiaoling

    2017-06-01

    Retinopathy of prematurity (ROP) is a major cause of childhood blindness in the world and is caused by oxygen-induced damage to the developing retinal vasculature, resulting in hyperoxia-induced vaso-obliteration and subsequent delayed retinal vascularization and hypoxia-induced pathological neovascularization driven by vascular endothelial growth factor (VEGF) signaling pathway in retina. Current anti-VEGF therapy has shown some effective in a clinical trial, but is associated with the unintended effects on delayed eye growth and retinal vasculature development of preterm infants. Notably, cellular responses to hypoxia are characterized by robust increases in extracellular adenosine production and the markedly induced adenosine receptors, which provide a novel target for preferential control of pathological angiogenesis without affecting normal vascular development. Here, we review the experimental evidence in support of adenosine receptor-based therapeutic strategy for ROP, including the aberrant adenosine signaling in oxygen-induced retinopathy and the role of three adenosine receptor subtypes (A 1 R, A 2A R, A 2B R) in development and treatment of ROP using oxygen-induced retinopathy models. The clinical and initial animal evidence that implicate the therapeutic effect of caffeine (a non-selective adenosine receptor antagonist) in treatment of ROP are highlighted. Lastly, we discussed the translational potential as well therapeutic advantage of adenosine receptor- and caffeine-based therapy for ROR and possibly other proliferative retinopathy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. High or low oxygen saturation and severe retinopathy of prematurity: a meta-analysis.

    Science.gov (United States)

    Chen, Minghua L; Guo, Lei; Smith, Lois E H; Dammann, Christiane E L; Dammann, Olaf

    2010-06-01

    Low oxygen saturation appears to decrease the risk of severe retinopathy of prematurity (ROP) in preterm newborns when administered during the first few weeks after birth. High oxygen saturation seems to reduce the risk at later postmenstrual ages (PMAs). However, previous clinical studies are not conclusive individually. To perform a systematic review and meta-analysis to report the association between severe ROP incidence of premature infants with high or low target oxygen saturation measured by pulse oximetry. Studies were identified through PubMed and Embase literature searches through May 2009 by using the terms "retinopathy of prematurity and oxygen" or "retinopathy of prematurity and oxygen therapy." We selected 10 publications addressing the association between severe ROP and target oxygen saturation measured by pulse oximetry. Using a random-effects model we calculated the summary-effect estimate. We visually inspected funnel plots to examine possible publication bias. Low oxygen saturation (70%-96%) in the first several postnatal weeks was associated with a reduced risk of severe ROP (risk ratio [RR]: 0.48 [95% confidence interval (CI): 0.31-0.75]). High oxygen saturation (94%-99%) at > or = 32 weeks' PMA was associated with a decreased risk for progression to severe ROP (RR: 0.54 [95% CI: 0.35-0.82]). Among preterm infants with a gestational age of large randomized clinical trial with long-term developmental follow-up is warranted to confirm this meta-analytic result.

  4. Linezolid induced retinopathy.

    Science.gov (United States)

    Park, Dae Hyun; Park, Tae Kwann; Ohn, Young-Hoon; Park, Jong Sook; Chang, Jee Ho

    2015-12-01

    While optic neuropathy is a well-known cause of visual disturbances in linezolid-treated patients, the possibility of linezolid-related retinopathy has not been investigated. Here, we report a case of retinopathy demonstrated by multifocal electroretinogram (mfERG) in a linezolid-treated patient. A 61-year-old man with extensively drug-resistant pulmonary tuberculosis treated with linezolid for 5 months presented with painless loss of vision in both eyes. The patient's best corrected visual acuity was 20/50 in the right eye and 20/100 in the left eye. Fundus examination revealed mild disc edema, and color vision was defective in both eyes. Humphrey visual field tests showed a superotemporal field defect in the right eye and central and pericentral field defect in the left eye. Optical coherence tomography (OCT) revealed only mild optic disc swelling. In mfERG, central amplitudes were depressed in both eyes. Four months after the cessation of linezolid, visual acuity was restored to 20/20 right eye and 20/25 left eye. The color vision and visual field had improved. The OCT and mfEFG findings improved as well. Although the clinical features were similar to linezolid-induced optic neuropathy, the mfERG findings suggest the possibility of a retinopathy through cone dysfunction.

  5. Impact of Chronic Neonatal Intermittent Hypoxia on Severity of Retinal Damage in a Rat Model of Oxygen-Induced Retinopathy.

    Science.gov (United States)

    Beharry, Kay D; Cai, Charles L; Ahmad, Taimur; Guzel, Sibel; Valencia, Gloria B; Aranda, Jacob V

    2018-01-01

    Neonatal intermittent hypoxia (IH) followed by re-oxygenation in normoxia or supplemental oxygen (IHR) increases the risk for severe retinopathy of prematurity (ROP). The exact timing for the onset of retinal damage which may guide strategic interventions during retinal development, is unknown. We tested the hypothesis that chronic exposure of the immature retina to neonatal IH induces early manifestations of retinal damage that can be utilized as key time points for strategic pharmacologic intervention. Newborn rats were exposed to IH within 2 hours of birth (P0) until P14, or allowed to recover in room air (RA) from P14 to P21 (IHR). Retinal integrity and angiogenesis biomarkers were progressively assessed before (P0), during IH, and post IH (recovery in RA), or IHR, and compared to normoxic age-matched controls. Retinal damage occurred as early as day 3 of neonatal IH, consistent with vascular abnormalities and disturbances in the astrocytic template. These abnormalities worsened during IHR. Pharmacologic and non-pharmacologic interventions to identify, prevent, or minimize neonatal IH should be implemented shortly after birth in high risk preterm newborns. This strategy may lead to a reduction in the outcome of severe ROP requiring later invasive treatments.

  6. Oxygen-Induced Retinopathy from Recurrent Intermittent Hypoxia Is Not Dependent on Resolution with Room Air or Oxygen, in Neonatal Rats.

    Science.gov (United States)

    Beharry, Kay D; Cai, Charles L; Skelton, Jacqueline; Siddiqui, Faisal; D'Agrosa, Christina; Calo, Johanna; Valencia, Gloria B; Aranda, Jacob V

    2018-05-01

    Preterm infants often experience intermittent hypoxia (IH) with resolution in room air (RA) or hyperoxia (Hx) between events. Hypoxia is a major inducer of vascular endothelial growth factor, which plays a key role in normal and aberrant retinal angiogenesis. This study tested the hypothesis that neonatal IH which resolved with RA is less injurious to the immature retina than IH resolved by Hx between events. Newborn rats were exposed to: (1) Hx (50% O₂) with brief hypoxia (12% O₂); (2) RA with 12% O₂; (3) Hx with RA; (4) Hx only; or (5) RA only, from P0 to P14. Pups were examined at P14 or placed in RA until P21. Retinal vascular and astrocyte integrity; retinal layer thickness; ocular and systemic biomarkers of angiogenesis; and somatic growth were determined at P14 and P21. All IH paradigms resulted in significant retinal vascular defects, disturbances in retinal astrocyte template, retinal thickening, and photoreceptor damage concurrent with elevations in angiogenesis biomarkers. These data suggest that the susceptibility of the immature retina to changes in oxygen render no differences in the outcomes between RA or O₂ resolution. Interventions and initiatives to curtail O₂ variations should remain a high priority to prevent severe retinopathy.

  7. Oxygen-Induced Retinopathy from Recurrent Intermittent Hypoxia Is Not Dependent on Resolution with Room Air or Oxygen, in Neonatal Rats

    Directory of Open Access Journals (Sweden)

    Kay D. Beharry

    2018-05-01

    Full Text Available Preterm infants often experience intermittent hypoxia (IH with resolution in room air (RA or hyperoxia (Hx between events. Hypoxia is a major inducer of vascular endothelial growth factor, which plays a key role in normal and aberrant retinal angiogenesis. This study tested the hypothesis that neonatal IH which resolved with RA is less injurious to the immature retina than IH resolved by Hx between events. Newborn rats were exposed to: (1 Hx (50% O2 with brief hypoxia (12% O2; (2 RA with 12% O2; (3 Hx with RA; (4 Hx only; or (5 RA only, from P0 to P14. Pups were examined at P14 or placed in RA until P21. Retinal vascular and astrocyte integrity; retinal layer thickness; ocular and systemic biomarkers of angiogenesis; and somatic growth were determined at P14 and P21. All IH paradigms resulted in significant retinal vascular defects, disturbances in retinal astrocyte template, retinal thickening, and photoreceptor damage concurrent with elevations in angiogenesis biomarkers. These data suggest that the susceptibility of the immature retina to changes in oxygen render no differences in the outcomes between RA or O2 resolution. Interventions and initiatives to curtail O2 variations should remain a high priority to prevent severe retinopathy.

  8. A machine learning approach for automated assessment of retinal vasculature in the oxygen induced retinopathy model.

    Science.gov (United States)

    Mazzaferri, Javier; Larrivée, Bruno; Cakir, Bertan; Sapieha, Przemyslaw; Costantino, Santiago

    2018-03-02

    Preclinical studies of vascular retinal diseases rely on the assessment of developmental dystrophies in the oxygen induced retinopathy rodent model. The quantification of vessel tufts and avascular regions is typically computed manually from flat mounted retinas imaged using fluorescent probes that highlight the vascular network. Such manual measurements are time-consuming and hampered by user variability and bias, thus a rapid and objective method is needed. Here, we introduce a machine learning approach to segment and characterize vascular tufts, delineate the whole vasculature network, and identify and analyze avascular regions. Our quantitative retinal vascular assessment (QuRVA) technique uses a simple machine learning method and morphological analysis to provide reliable computations of vascular density and pathological vascular tuft regions, devoid of user intervention within seconds. We demonstrate the high degree of error and variability of manual segmentations, and designed, coded, and implemented a set of algorithms to perform this task in a fully automated manner. We benchmark and validate the results of our analysis pipeline using the consensus of several manually curated segmentations using commonly used computer tools. The source code of our implementation is released under version 3 of the GNU General Public License ( https://www.mathworks.com/matlabcentral/fileexchange/65699-javimazzaf-qurva ).

  9. Lutein facilitates physiological revascularization in a mouse model of retinopathy of prematurity.

    Science.gov (United States)

    Fu, Zhongjie; Meng, Steven S; Burnim, Samuel B; Smith, Lois Eh; Lo, Amy Cy

    2017-07-01

    Retinopathy of prematurity is one of the leading causes of childhood blindness worldwide, with vessel growth cessation and vessel loss in phase I followed by neovascularization in phase II. Ischaemia contributes to its pathogenesis, and lutein protects against ischaemia-induced retinal damages. We aimed to investigate the effects of lutein on a murine model of oxygen-induced retinopathy. Mouse pups were exposed to 75% oxygen for 5 days and returned to room air for another 5 days. Vascular obliteration, neovascularization and blood vessel leakage were examined. Immunohistochemistry for glial cells and microglia were performed. Compared with vehicle controls, mouse pups receiving lutein treatment displayed smaller central vaso-obliterated area and reduced blood vessel leakage. No significant difference in neovascular area was found between lutein and vehicle controls. Lutein promoted endothelial tip cell formation and maintained the astrocytic template in the avascular area in oxygen-induced retinopathy. No significant changes in Müller cell gliosis and microglial activation in the central avascular area were found in lutein-treated pups. Our observations indicated that lutein significantly promoted normal retinal vascular regrowth in the central avascular area, possibly through promoting endothelial tip cell formation and preserving astrocytic template. Our results indicated that lutein might be considered as a supplement for the treatment of proliferative retinopathy of prematurity because of its role in facilitating the revascularization of normal vasculature. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

  10. Lack of differences in the regional variation of oxygen saturation in larger retinal vessels in diabetic maculopathy and proliferative diabetic retinopathy.

    Science.gov (United States)

    Jørgensen, Christina Mørup; Bek, Toke

    2017-06-01

    Diabetic retinopathy is characterised by morphological lesions in the ocular fundus related to disturbances in retinal blood flow. The two vision threatening forms of retinopathy show specific patterns of distribution of retinal lesions with proliferative diabetic retinopathy (PDR) developing secondary to ischaemia and hypoxia in the retinal periphery and diabetic maculopathy (DM) developing secondary to hyperperfusion and increased vascular permeability in the macular area. These differences in the distribution of retinal lesions might be reflected in regional differences in oxygen saturation in the larger retinal vessels. Dual-wavelength retinal oximetry was performed in 30 normal persons, 30 patients with DM and 30 patients with PDR, and the oxygen saturation was measured in peripapillary vessels supplying the four retinal quadrants and in branches from the upper temporal arcades supplying, respectively, the macular area and the retinal periphery. The overall oxygen saturation was significantly higher in diabetic patients than in normal persons and the arteriovenous (AV) saturation difference significantly lower in the patients with DM. The regional variation in oxygen saturation was similar in the three studied groups with a decreasing saturation from the upper nasal through the lower nasal, lower temporal and the upper temporal peripapillary vessels, and with a significantly higher oxygen saturation in venules draining the macular area than in venules draining the retinal periphery. The regional differences in retinal lesions in vision threatening diabetic retinopathy are not reflected in regional differences in the oxygen saturation of larger retinal vessels. The development of vision threatening diabetic retinopathy depends on other factors, such as, for example, regional differences in the retinal microcirculation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  11. Radiation retinopathy caused by low dose irradiation and antithyroid drug-induced systemic vasculitis

    International Nuclear Information System (INIS)

    Sonoda, Koh-hei; Ishibashi, Tatsuro

    2005-01-01

    We report on a patient with Graves' disease with radiation retinopathy caused by low-dose irradiation and antithyroid drug-induced antineutrophil cytoplasmic antibody (ANCA)-positive vasculitis. A 38-year-old woman with Graves' disease presented with bilateral blurred vision, micro-aneurysms, telangiectasia, and macular edema. The patient was examined by ophthalmoscopy and fluorescein angiography, and radiation retinopathy was diagnosed. The patient had been treated with low-dose irradiation for her Graves' ophthalmopathy a few years earlier. She also had ANCA-positive vasculitis induced by the antithyroid drug (propylthiouracil, PTU) that had been prescribed for her at that time. Because of multiple avascular areas on both retinas, she was treated by intensive retinal photocoagulation to control progressive retinopathy. The radiation doses used to treat Graves' disease ophthalmopathy are low. Nevertheless, there is still a risk of radiation retinopathy developing in patients with PTU-induced ANCA-positive vasculitis. (author)

  12. The Rat With Oxygen-Induced Retinopathy Is Myopic With Low Retinal Dopamine

    OpenAIRE

    Zhang, Nan; Favazza, Tara L.; Baglieri, Anna Maria; Benador, Ilan Y.; Noonan, Emily R.; Fulton, Anne B.; Hansen, Ronald M.; Iuvone, P. Michael; Akula, James D.

    2013-01-01

    The rat model of retinopathy of prematurity (the 'ROP rat') is found to be the first known animal model of myopia in which the eye is smaller than normal. Data suggests that reduced retinal dopamine metabolism may contribute to the peculiar myopia of ROP.

  13. Retinal oxygen extraction in individuals with type 1 diabetes with no or mild diabetic retinopathy.

    Science.gov (United States)

    Fondi, Klemens; Wozniak, Piotr A; Howorka, Kinga; Bata, Ahmed M; Aschinger, Gerold C; Popa-Cherecheanu, Alina; Witkowska, Katarzyna J; Hommer, Anton; Schmidl, Doreen; Werkmeister, René M; Garhöfer, Gerhard; Schmetterer, Leopold

    2017-08-01

    The aim of this study was to compare retinal oxygen extraction in individuals with diabetes with no or mild non-proliferative diabetic retinopathy and healthy age- and sex-matched volunteers. A total of 24 participants with type 1 diabetes and 24 healthy age- and sex-matched volunteers were included in this cross-sectional study. Retinal oxygen extraction was measured by combining total retinal blood flow measurements using a custom-built bi-directional Doppler optical coherence tomography system with measurements of oxygen saturation using spectroscopic reflectometry. Based on previously published mathematical modelling, the oxygen content in retinal vessels and total retinal oxygen extraction were calculated. Total retinal blood flow was higher in diabetic participants (46.4 ± 7.4 μl/min) than in healthy volunteers (40.4 ± 5.3 μl/min, p = 0.002 between groups). Oxygen content in retinal arteries was comparable between the two groups, but oxygen content in retinal veins was higher in participants with diabetes (0.15 ± 0.02 ml O 2 /ml) compared with healthy control participants (0.13 ± 0.02 ml O 2 /ml, p diabetes compared with healthy volunteers (total retinal oxygen extraction 1.40 ± 0.44 vs 1.70 ± 0.47 μl O 2 /min, respectively, p = 0.03). Our data indicate early retinal hypoxia in individuals with type 1 diabetes with no or mild diabetic retinopathy as compared with healthy control individuals. Further studies are required to fully understand the potential of the technique in risk stratification and treatment monitoring. ClinicalTrials.gov NCT01843114.

  14. Mechanisms involved in the development of diabetic retinopathy induced by oxidative stress.

    Science.gov (United States)

    Guzman, David Calderón; Olguín, Hugo Juárez; García, Ernestina Hernández; Peraza, Armando Valenzuela; de la Cruz, Diego Zamora; Soto, Monica Punzo

    2017-01-01

    Diabetic retinopathy (DR) is one of the main complications in patients with diabetes and has been the leading cause of visual loss since 1990. Oxidative stress is a biological process resulting from excessive production of reactive oxygen species (ROS). This process contributes to the development of many diseases and disease complications. ROS interact with various cellular components to induce cell injury. Fortunately, there is an antioxidan t system that protects organisms against ROS. Indeed, when ROS exceed antioxidant capacity, the resulting cell injury can cause diverse physiological and pathological changes that could lead to a disease like DR. This paper reviews the possible mechanisms of common and novel biomarkers involved in the development of DR and explores how these biomarkers could be used to monitor the damage induced by oxidative stress in DR, which is a significant complication in people with diabetes. The poor control of glucemy in pacients with DB has been shown contribute to the development of complications in eyes as DR.

  15. Hydroxychloroquine Induced Retinopathy: A Case Series

    Directory of Open Access Journals (Sweden)

    Maryam Mobini

    2016-10-01

    Full Text Available Background and Purpose: Occular toxicity is one of the most important complications of Hydroxychloroquine. Not any type of treatment has so far been found and recommended for this disorder. The purpose of this study was to report some characteristics of patients with Hydroxychloroquine Induced Retinopathy.    Materials and Methods: From 107 patients with rheumatoid arthritis (RA and/or systemic lupus erythematosus (SLE during 2013-14 in Sari, Iran, who were selected by a simple sampling method and were referred to hospitals for ophthalmologic examinations, 21 patients were found with HCQ induced retinopathy. The Examination for HCQ-induced maculopathy was performed through fundoscopy, perimetry or optical coherence tomography (OCT, and the physicians had their own discretion based on the examination. Although the patients were examined by different ophthalmologists, all of them were evaluated by the same device (Zeiss cirrus HD OCT4000.USA for OCT, Zeiss Humphrey Field analyzer 2i. USA for visual field, and Topcon. TRC.50Dx. Japan for angiography. Based on the collected data, the characteristics of clinical and ophthalmologic changes were reported, and the data were analysed through Independent Sample t Test and χ2.    Results: 21 patients (19 females with a mean age of 49.86 (±15.6 were evaluated during 4.95 (±4.7 years of therapy. The mean of cumulative dose was calculated to be 313.18±269.8 grams. Based on the findings, hypertension was detected in 5 (23.8% of the patients. Conclusion: In the present study, it was found that HCQ induced retinal toxicity may occur even in recommended doses or for less than 5 years. Other risk factors such as hypertension in addition to the dose or duration of toxicity could also accelerate retinal toxicity.

  16. Ocular Adverse Effects of Intravitreal Bevacizumab Are Potentiated by Intermittent Hypoxia in a Rat Model of Oxygen-Induced Retinopathy

    Directory of Open Access Journals (Sweden)

    Jeffrey J. Tan

    2017-01-01

    Full Text Available Intravitreal bevacizumab (Avastin use in preterm infants with retinopathy of prematurity is associated with severe neurological disabilities, suggesting vascular leakage. We examined the hypothesis that intermittent hypoxia (IH potentiates intravitreal Avastin leakage. Neonatal rats at birth were exposed to IH from birth (P0–P14. At P14, the time of eye opening in rats, a single dose of Avastin (0.125 mg was injected intravitreally into the left eye. Animals were placed in room air (RA until P23 or P45 for recovery (IHR. Hyperoxia-exposed and RA littermates served as oxygen controls, and equivalent volume saline served as the placebo controls. At P23 and P45 ocular angiogenesis, retinal pathology and ocular and systemic biomarkers of angiogenesis were examined. Retinal flatmounts showed poor peripheral vascularization in Avastin-treated and fellow eyes at P23, with numerous punctate hemorrhages and dilated, tortuous vessels with anastomoses at P45 in the rats exposed to IH. These adverse effects were associated with robust increases in systemic VEGF and in both treated and untreated fellow eyes. Histological analysis showed severe damage in the inner plexiform and inner nuclear layers. Exposure of IH/IHR-induced injured retinal microvasculature to anti-VEGF substances can result in vascular leakage and adverse effects in the developing neonate.

  17. Arginase in Retinopathy

    Science.gov (United States)

    Narayanan, S. Priya; Rojas, Modesto; Suwanpradid, Jutamas; Toque, Haroldo A.; Caldwell, R. William; Caldwell, Ruth B.

    2013-01-01

    Ischemic retinopathies, such as diabetic retinopathy (DR), retinopathy of prematurity and retinal vein occlusion are a major cause of blindness in developed nations worldwide. Each of these conditions is associated with early neurovascular dysfunction. However, conventional therapies target clinically significant macula edema or neovascularization, which occur much later. Intraocular injections of anti-VEGF show promise in reducing retinal edema, but the effects are usually transient and the need for repeated injections increases the risk of intraocular infection. Laser photocoagulation can control pathological neovascularization, but may impair vision and in some patients the retinopathy continues to progress. Moreover, neither treatment targets early stage disease or promotes repair. This review examines the potential role of the ureahydrolase enzyme arginase as a therapeutic target for the treatment of ischemic retinopathy. Arginase metabolizes L-arginine to form proline, polyamines and glutamate. Excessive arginase activity reduces the L-arginine supply for nitric oxide synthase (NOS), causing it to become uncoupled and produce superoxide and less NO. Superoxide and NO react and form the toxic oxidant peroxynitrite. The catabolic products of polyamine oxidation and glutamate can induce more oxidative stress and DNA damage, both of which can cause cellular injury. Studies indicate that neurovascular injury during retinopathy is associated with increased arginase expression/activity, decreased NO, polyamine oxidation, formation of superoxide and peroxynitrite and dysfunction and injury of both vascular and neural cells. Furthermore, data indicate that the cytosolic isoform arginase I (AI) is involved in hyperglycemia-induced dysfunction and injury of vascular endothelial cells whereas the mitochondrial isoform arginase II (AII) is involved in neurovascular dysfunction and death following hyperoxia exposure. Thus, we postulate that activation of the arginase

  18. Comparison of Dextran Perfusion and GSI-B4 Isolectin Staining in a Mouse Model of Oxygen-induced Retinopathy.

    Science.gov (United States)

    Huang, Shaofen; Liang, Jiajian; Yam, Gary Hin-Fai; Lu, Zhihao; Pang, Chi Pui; Chen, Haoyu

    2015-06-01

    Oxygen-induced retinopathy (OIR) is a robust and widely used animal model for the study of retinal neovascularization (NV). Dextran perfusion and Griffonia simplicifolia isolectin B4 (GSI-B4) staining are two common methods for examining the occurrence and extent of OIR. This study provides a quantitative comparison of the two for OIR detection. At postnatal day 7 (PN7), fifteen C57BL/6J mice were exposed to a 75% hyperoxic condition for 5 days and then returned to room air conditions. At PN17, the mice received intravitreal injection of GSI-B4 Alexa Fluor 568 conjugate. After 10 hours, they were infused with FITC-dextran conjugate via the left ventricle. Retinal flat mounts were photographed by confocal microscopy. Areas with fluorescent signals and the total retinal areas were quantified by Image J software. Both GSI-B4 and dextran detected the peripheral neovascular area. The mean hyper fluorescence area was 0.33 ± 0.14% of whole retinal area determined by GSI-B4 staining and 0.25 ± 0.28% determined by dextran perfusion. The difference between the two measures was 0.08% (95% CI:-0.59%, 0.43%). The Pearson correlation coefficient between the two methods was 0.386,P =0.035. The mean coincidence rates were 14.3 ± 13.4% and 24.9 ± 18.5% for GSI-B4 and dextran staining, respectively. Both methods can complement each other in demonstrating and quantitatively evaluating retinal NV. A poor agreement was found between the two methods; GSI-B4 isolectin was more effective than FITC-dextran perfusion in evaluating the extent of retinal NV in a mouse model of OIR.

  19. Hypoxia-induced retinal neovascularization in zebrafish embryos: a potential model of retinopathy of prematurity.

    Science.gov (United States)

    Wu, Yu-Ching; Chang, Chao-Yuan; Kao, Alex; Hsi, Brian; Lee, Shwu-Huey; Chen, Yau-Hung; Wang, I-Jong

    2015-01-01

    Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2-4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression.

  20. Noninvasive Retinal Markers in Diabetic Retinopathy

    DEFF Research Database (Denmark)

    Blindbæk, Søren Leer; Torp, Thomas Lee; Lundberg, Kristian

    2017-01-01

    The retinal vascular system is the only part of the human body available for direct, in vivo inspection. Noninvasive retinal markers are important to identity patients in risk of sight-threatening diabetic retinopathy. Studies have correlated structural features like retinal vascular caliber...... and fractals with micro- and macrovascular dysfunction in diabetes. Likewise, the retinal metabolism can be evaluated by retinal oximetry, and higher retinal venular oxygen saturation has been demonstrated in patients with diabetic retinopathy. So far, most studies have been cross-sectional, but these can only...... retinopathy and diabetic macular edema. The Department of Ophthalmology at Odense University Hospital, Denmark, has a strong tradition of studying the retinal microvasculature in diabetic retinopathy. In the present paper, we demonstrate the importance of the retinal vasculature not only as predictors of long...

  1. Bevacizumab treatment reduces retinal neovascularization in a mouse model of retinopathy of prematurity

    Institute of Scientific and Technical Information of China (English)

    Fei; Feng; Yan; Cheng; Qing-Huai; Liu

    2014-01-01

    ·AIM: To evaluate the effect of different bevacizumab concentrations on retinal neovascularization in a retinopathy of prematurity(ROP) mouse model.·METHODS: A total of 60 of C57BL/6 J mice were exposed to 75% ±2% oxygen from postnatal d7 to postnatal d12. Fifteen nonexposed mice served as negative controls(group A). On d12, 30 mice(group C)were injected with 2.5 μg intravitreal bevacizumab(IVB),30 mice(group D) were injected with 1.25 μg IVB in one eye. The contralateral eyes were injected with balanced salt solution(BSS)(control group =group B). The adenosine diphosphatase(ADPase) histochemical technique was used for retinal flat mount to assess the oxygen-induced changes of retinal vessels.Neovascularization was quantified by counting the endothelial cell proliferation on the vitreal side of the inner limiting membrane of the retina. Histological changes were examined by light microscopy. The mRNA levels of vascular endothelial growth factor(VEGF) were quantified by Real-time PCR. Western-blotting analysis was performed to examine the expression of P-VEGFR.· RESULTS: Comparing with the control group B,regular distributions and reduced tortuosity of vessels were observed in our retinal flat mounts in groups C and D. The endothelial cell count per histological section was lower in groups C(P <0.0001) and D(P <0.0001) compared with the control group B. Histological evaluation showed no retinal toxicity in any group. In all oxygen treated groups VEGF mRNA expression was significantly increased as compared to age-matched controls. No significant change in VEGF mRNA expression could be achieved in either of the treatments or the oxygen controls. The results of the Western blot were consistent with that of the Real-time PCR analysis.·CONCLUSION: An intravitreal injection of bevacizumab is able to reduce angioproliferative retinopathy in a mouse model for oxygen-induced retinopathy.

  2. Retinal Oxygen Delivery and Metabolism in Healthy and Sickle Cell Retinopathy Subjects.

    Science.gov (United States)

    Shahidi, Mahnaz; Felder, Anthony E; Tan, Ou; Blair, Norman P; Huang, David

    2018-04-01

    Reduction in inner retinal oxygen delivery (DO2) can cause retinal hypoxia and impair inner retinal oxygen metabolism (MO2), leading to vision loss. The purpose of the current study was to establish measurements of DO2 and MO2 in healthy subjects and test the hypothesis that DO2 and MO2 are reduced in sickle cell retinopathy (SCR) subjects. Dual wavelength retinal oximetry and Doppler optical coherence tomography were performed in 12 healthy control and 12 SCR subjects. Images were analyzed to measure retinal arterial and venous oxygen content (O2A and O2V), venous diameter (DV), and total retinal blood flow (TRBF). Retinal arteriovenous oxygen content difference (O2AV), DO2, MO2, and oxygen extraction fraction (OEF) were calculated according to the following equations: O2AV = O2A - O2V; DO2 = TRBF * O2A; MO2 = TRBF * O2AV; OEF = MO2/DO2. Retinal DV and TRBF were higher in the SCR group as compared to the control group, whereas, O2A, O2V, and O2AV were lower in SCR group as compared to the control group. DO2, MO2, and OEF were not significantly different between control and SCR groups. MO2 and DO2 were linearly related, such that higher MO2 was associated with higher DO2. There was an inverse relationship between TRBF and OEF, such that lower TRBF was associated with higher OEF. Increased blood flow compensated for decreased oxygen content, thereby maintaining DO2, MO2, and OEF at predominately lower stages of SCR. Quantitative assessment of these parameters has the potential to advance knowledge and improve diagnostic evaluation of retinal ischemic conditions.

  3. Hyperoxia-Induced Proliferative Retinopathy: Early Interruption of Retinal Vascular Development with Severe and Irreversible Neurovascular Disruption.

    Directory of Open Access Journals (Sweden)

    Michelle Lajko

    Full Text Available Bronchopulmonary dysplasia (BPD is a major cause of neonatal morbidity in premature infants, occurring as a result of arrested lung development combined with multiple postnatal insults. Infants with BPD exposed to supplemental oxygen are at risk of retinopathy of prematurity as well. Thus, we studied the effects of hyperoxia on the retinal vasculature in a murine model of BPD. The retinal phenotype of this model, which we termed hyperoxia-induced proliferative retinopathy (HIPR, shows severe disruption of retinal vasculature and loss of vascular patterning, disorganized intra-retinal angiogenesis, inflammation and retinal detachment. Neonatal mice were subjected to 75% oxygen exposure from postnatal day (P0 to P14 to model BPD, then allowed to recover in room air for 1 (P15, 7 (P21, or 14 days (P28. We quantified retinal thickness, protein levels of HIF-1α, NOX2, and VEGF, and examined the cellular locations of these proteins by immunohistochemistry. We examined the retinal blood vessel integrity and inflammatory markers, including macrophages (F4/80 and lymphocytes (CD45R. Compared to controls, normal retinal vascular development was severely disrupted and replaced by a disorganized sheet of intra-retinal angiogenesis in the HIPR mice. At all time-points, HIPR showed persistent hyaloidal vasculature and a significantly thinner central retina compared to controls. HIF-1α protein levels were increased at P15, while VEGF levels continued to increase until P21. Intra-retinal fibrinogen was observed at P21 followed by sub-retinal deposition in at P28. Inflammatory lymphocytes and macrophages were observed at P21 and P28, respectively. This model presents a severe phenotype of disrupted retinal vascular development, intra-retinal angiogenesis inflammation and retinal detachment.

  4. Features of retinopathy of prematurity in a tertiary care hospital in Lahore.

    Science.gov (United States)

    Jamil, Ahmad Zeeshan; Tahir, Muhammad Younis; Ayub, Muhammad Hammad; Mirza, Khurram Azam

    2015-02-01

    To study the demographic and clinical features of Retinopathy of Prematurity in urban Punjab. The cross-sectional study was performed at Hameed Latif Hospital, Lahore, from April 2010 to October 2013 and comprised neonates born with birth weight less than 2000 g, gestational age less than 37 weeks, or those who were considered high risk for Retinopathy of Prematurity. Variables recorded included history, birth weight, gestational age, oxygen supplementation, development of Retinopathy of Prematurity, and laser treatment. Data was analysed using SPSS 17. There were 285 neonates in the study with a mean birth weight of 1280.34 ± 350.43 g and mean gestational age being 29.38 ± 3.14 weeks. Overall, 167 (58.6%) received supplemental oxygen, 86(30.2%) were anaemic and 44 (15.4%) received blood transfusion. Besides, 47 (16.5%) premature babies were product of multiple gestation, 34 (11.9%) were having respiratory distress, 25 (8.8%) had sepsis and received intravenous antibiotics, 70(24.6%) developed Retinopathy of Prematurity, and 22 (7.7%) developed threshold disease and received laser treatment at mean gestational age of 32.11 ± 2.53 weeks. Screening is key to preventing childhood blindness caused by Retinopathy of Prematurity. Prematurity, low birth weight and supplemental oxygen therapy are significant risk factors for the condition.

  5. Educational paper: Retinopathy of prematurity.

    Science.gov (United States)

    Casteels, Ingele; Cassiman, Catherine; Van Calster, Joachim; Allegaert, Karel

    2012-06-01

    Retinopathy of prematurity (ROP) is a proliferative retinal vascular disease affecting the premature infant with an incompletely vascularized retina. The spectrum of ophthalmological findings in ROP exists from minimal sequelae, which do not affect vision, to bilateral retinal detachment and total blindness. With the increased survival of very small infants, retinopathy of prematurity has become one of the leading causes of childhood blindness. Over the past two decades, major advances have been made in understanding the pathogenesis of ROP, to a large extent as a result of changes in clinical risk factors (oxygen and non-oxygen related) and characteristics observed in ROP cases. This article provides a literature review on the evolution in clinical characteristics, classification and treatment modalities and indications of ROP. Special attention is hereby paid to the neonatal factors influencing the development of ROP and to the necessity for everyone caring for premature babies to have a well-defined screening and treatment protocol for ROP. Such screening protocol needs to be based on a unit-specific ROP risk profile and, consequently, may vary between different European regions. Retinopathy of prematurity is an important cause of ocular morbidity and blindness in children. With better understanding of the pathogenesis, screening and treatment guidelines have changed over time and are unit specific.

  6. NADPH Oxidase, NOX1, Mediates Vascular Injury in Ischemic Retinopathy

    Science.gov (United States)

    Deliyanti, Devy; Rana, Indrajeetsinh; Miller, Antonia G.; Agrotis, Alex; Armani, Roksana; Szyndralewiez, Cédric; Wingler, Kirstin; Touyz, Rhian M.; Cooper, Mark E.; Jandeleit-Dahm, Karin A.; Schmidt, Harald H.H.W.

    2014-01-01

    Abstract Aims: Ischemic retinal diseases such as retinopathy of prematurity are major causes of blindness due to damage to the retinal microvasculature. Despite this clinical situation, retinopathy of prematurity is mechanistically poorly understood. Therefore, effective preventative therapies are not available. However, hypoxic-induced increases in reactive oxygen species (ROS) have been suggested to be involved with NADPH oxidases (NOX), the only known dedicated enzymatic source of ROS. Our major aim was to determine the contribution of NOX isoforms (1, 2, and 4) to a rodent model of retinopathy of prematurity. Results: Using a genetic approach, we determined that only mice with a deletion of NOX1, but not NOX2 or NOX4, were protected from retinal neovascularization and vaso-obliteration, adhesion of leukocytes, microglial accumulation, and the increased generation of proangiogenic and proinflammatory factors and ROS. We complemented these studies by showing that the specific NOX inhibitor, GKT137831, reduced vasculopathy and ROS levels in retina. The source of NOX isoforms was evaluated in retinal vascular cells and neuro-glial elements. Microglia, the immune cells of the retina, expressed NOX1, 2, and 4 and responded to hypoxia with increased ROS formation, which was reduced by GKT137831. Innovation: Our studies are the first to identify the NOX1 isoform as having an important role in the pathogenesis of retinopathy of prematurity. Conclusions: Our findings suggest that strategies targeting NOX1 have the potential to be effective treatments for a range of ischemic retinopathies. Antioxid. Redox Signal. 20, 2726–2740. PMID:24053718

  7. Analysis on screening results of 2 203 premature infants with retinopathy

    Directory of Open Access Journals (Sweden)

    Qian Wang

    2018-06-01

    Full Text Available AIM: To investigate the incidence and risk factors of retinopathy of prematurity(ROPin preterm infants. METHODS: The wide-field digital pediatric Retinal imaging system was used to screen 2 203 preterm infants with gestational age RESULTS: Totally 367 infants(621 eyeswere diagnosed as retinopathy among 2 203 premature infants and the incidence of ROP was 16.66%; 236 cases(399 eyesof ROP(26.61%were detected in 887 cases of premature infants in accord with screening standard of the Chinese Premature Retinopathy Screening Guidelines(2014, and 131 cases(222 eyesof ROP(9.95%was detected in 1 316 cases of premature infants outside the screening standard. In our research, the incidence of ROP was related with gestational age, birth weight, oxygen duration and mechanical ventilation. However, the relationship had not been found with artificial insemination, caesarean birth, gender, polyembryony, acute respiratory distress syndrome(ARDS, hypertensive disorders in pregnancy, gestational diabetes mellitus, intrauterine infection, intrauterine distress, premature rupture of membrane. The incidence of ROP was statistically significant between different gestational age groups, different birth weight groups and different oxygen groups(PCONCLUSION: The incidence of ROP is 16.66% in this study, and there is still a certain proportion outside the screening standard of the Chinese Premature Retinopathy Screening Guidelines(2014. Gestational age, birth weight, oxygen duration and mechanical ventilation are high risk factors for ROP.

  8. Following-up study on radiation-induced retinopathy in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Zhang Qingping; Zhou Weiwei; Xie Chengxi; Huang Guangwu; Ruan Lin

    2003-01-01

    Objective: To investigate the frequency of ocular complication and the quality of patient's life after radiation therapy in nasopharyngeal carcinoma (NPC). Methods: 254 NPC patients who initially received radiation were followed and analysed. Visual acuity, automational visual field, slit-lamp microscopic findings, pattern visual evoked potential (P-VEP) and fundal findings were determined before, during and after radiation therapy. The severity of retinal impairment was assessed according to the international criteria on late tissue effects. Results: The radiation dose was more than 70 Gy in 241 (94.9%)NPC patients, giving a radiation retinopathy incidence of 8.7% (22) patients after a mean of 46.8±14.4 months. After being diagnosed as radiation retinopathy, 16 patients received combined-modality therapy of the modern medicine and Chinese traditional medicine. The disease condition was controlled in 56%(9) patients but progressed into optic neuropathy in 7 patients, 3 of whom developed radiation encephalopathy in 14 to 20 months after onset of retinopathy. The morbidity of radiation retinopathy was not associated with the patient's age, but was related to the radiation dose. The retinopathy rate was as high as 13.6% in the 75-79 Gy group, which is significantly higher than 5.6% in the 70-74 Gy group (P<0.05). Conclusions: Radiation retinopathy in NPC patients is related to the radiation dose and individual difference in radiosensitivity. Optic nerve and brain damage are already present when clinical manifestations of radiation retinopathy occur. Therefore CT and MRI of the brain should be carried out. The importance of long-term follow-up should be stressed for early diagnosis and treatment of radiation sequelae for the sake of complete return of visual function and good quality of life

  9. Functional Deficits Precede Structural Lesions in Mice With High-Fat Diet-Induced Diabetic Retinopathy.

    Science.gov (United States)

    Rajagopal, Rithwick; Bligard, Gregory W; Zhang, Sheng; Yin, Li; Lukasiewicz, Peter; Semenkovich, Clay F

    2016-04-01

    Obesity predisposes to human type 2 diabetes, the most common cause of diabetic retinopathy. To determine if high-fat diet-induced diabetes in mice can model retinal disease, we weaned mice to chow or a high-fat diet and tested the hypothesis that diet-induced metabolic disease promotes retinopathy. Compared with controls, mice fed a diet providing 42% of energy as fat developed obesity-related glucose intolerance by 6 months. There was no evidence of microvascular disease until 12 months, when trypsin digests and dye leakage assays showed high fat-fed mice had greater atrophic capillaries, pericyte ghosts, and permeability than controls. However, electroretinographic dysfunction began at 6 months in high fat-fed mice, manifested by increased latencies and reduced amplitudes of oscillatory potentials compared with controls. These electroretinographic abnormalities were correlated with glucose intolerance. Unexpectedly, retinas from high fat-fed mice manifested striking induction of stress kinase and neural inflammasome activation at 3 months, before the development of systemic glucose intolerance, electroretinographic defects, or microvascular disease. These results suggest that retinal disease in the diabetic milieu may progress through inflammatory and neuroretinal stages long before the development of vascular lesions representing the classic hallmark of diabetic retinopathy, establishing a model for assessing novel interventions to treat eye disease. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  10. Jiangtang Xiaozhi Recipe () prevents diabetic retinopathy in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Li, Lin; Li, Yan-Lin; Zhou, Yun-Feng; Ge, Zheng-Yan; Wang, Li-Li; Li, Zhi-Qiang; Guo, Yu-Jie; Jin, Long; Ren, Ye; Liu, Jian-Xun; Xu, Yang

    2017-06-01

    To evaluate the prevention effect of diabetic retinopathy of Jiangtang Xiaozhi Recipe (, JXR) in streptozotocin (STZ)-induced diabetic rats. Sprague-Dawley rats were randomly divided into normal control group and diabetic group. Rats in the diabetic group were induced by intraperitoneal administration of STZ (50 mg/kg), and subdivided into 5 groups. Rats in the diabetic control group were given saline; four treatment groups were given metformin (300 mg/kg), JXR (2, 4 and 8 g/kg) respectively for 8 weeks, while rats in the normal control group were injected with citrate buffer and given the same volume of vehicle. Body weight and food intake were measured every week. The hypoglycaemic effects were determined by testing fasting blood glucose (FBG) every other week, and hemoglobin A1c (HbA1c), insulin, and glucagon at the end of the treatment. The preventive effects of JXR on STZ-induced diabetic rats were determined by histopathological examination with hematoxylin and eosin staining, and periodic acid-schiff staining. The effects were further evaluated by serum superoxide dismutase (SOD) activity and malondialdehyde (MDA). High-dose JXR significantly reduced FBG and HbA1c level at the 8th week of administration (Pdiabetic rats. Histopathological studies revealed that there were no basement membrane thickening and mild destruction in the treated groups. Morphometric measurements of retina microvascular showed that acellular capillary and capillary density decreased in treated rats while pericyte and endothelial cell increasing after the treatment. JXR have protective effect of diabetic retinopathy and its mechanism may be associated with the obvious hypoglycemic and antioxidant effect.

  11. The pleiotropic effects of simvastatin on retinal microvascular endothelium has important implications for ischaemic retinopathies.

    Directory of Open Access Journals (Sweden)

    Reinhold J Medina

    Full Text Available BACKGROUND: Current guidelines encourage the use of statins to reduce the risk of cardiovascular disease in diabetic patients; however the impact of these drugs on diabetic retinopathy is not well defined. Moreover, pleiotropic effects of statins on the highly specialised retinal microvascular endothelium remain largely unknown. The objective of this study was to investigate the effects of clinically relevant concentrations of simvastatin on retinal endothelium in vitro and in vivo. METHODS AND FINDINGS: Retinal microvascular endothelial cells (RMECs were treated with 0.01-10 microM simvastatin and a biphasic dose-related response was observed. Low concentrations enhanced microvascular repair with 0.1 microM simvastatin significantly increasing proliferation (p<0.05, and 0.01 microM simvastatin significantly promoting migration (p<0.05, sprouting (p<0.001, and tubulogenesis (p<0.001. High concentration of simvastatin (10 microM had the opposite effect, significantly inhibiting proliferation (p<0.01, migration (p<0.01, sprouting (p<0.001, and tubulogenesis (p<0.05. Furthermore, simvastatin concentrations higher than 1 microM induced cell death. The mouse model of oxygen-induced retinopathy was used to investigate the possible effects of simvastatin treatment on ischaemic retinopathy. Low dose simvastatin (0.2 mg/Kg promoted retinal microvascular repair in response to ischaemia by promoting intra-retinal re-vascularisation (p<0.01. By contrast, high dose simvastatin(20 mg/Kg significantly prevented re-vascularisation (p<0.01 and concomitantly increased pathological neovascularisation (p<0.01. We also demonstrated that the pro-vascular repair mechanism of simvastatin involves VEGF stimulation, Akt phosphorylation, and nitric oxide production; and the anti-vascular repair mechanism is driven by marked intracellular cholesterol depletion and related disorganisation of key intracellular structures. CONCLUSIONS: A beneficial effect of low

  12. Endogenous erythropoietin protects neuroretinal function in ischemic retinopathy.

    Science.gov (United States)

    Mowat, Freya M; Gonzalez, Francisco; Luhmann, Ulrich F O; Lange, Clemens A; Duran, Yanai; Smith, Alexander J; Maxwell, Patrick H; Ali, Robin R; Bainbridge, James W B

    2012-04-01

    Because retinal ischemia is a common cause of vision loss, we sought to determine the effects of ischemia on neuroretinal function and survival in murine oxygen-induced retinopathy (OIR) and to define the role of endogenous erythropoietin (EPO) in this model. OIR is a reproducible model of ischemia-induced retinal neovascularization; it is used commonly to develop antiangiogenic strategies. We investigated the effects of ischemia in murine OIR on retinal function and neurodegeneration by electroretinography and detailed morphology. OIR was associated with significant neuroretinal dysfunction, with reduced photopic and scotopic ERG responses and reduced b-wave/a-wave ratios consistent with specific inner-retinal dysfunction. OIR resulted in significantly increased apoptosis and atrophy of the inner retina in areas of ischemia. EPO deficiency in heterozygous Epo-Tag transgenic mice was associated with more profound retinal dysfunction after OIR, indicated by a significantly greater suppression of ERG amplitudes, but had no measurable effect on the extent of retinal ischemia, preretinal neovascularization, or neuroretinal degeneration in OIR. Systemic administration of recombinant EPO protected EPO-deficient mice against this additional suppression, but EPO supplementation in wild-type animals with OIR did not rescue neuroretinal dysfunction or degeneration. Murine OIR offers a valuable model of ischemic neuroretinal dysfunction and degeneration in which to investigate adaptive tissue responses and evaluate novel therapeutic approaches. Endogenous EPO can protect neuroretinal function in ischemic retinopathy. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  13. Downregulated Brain-Derived Neurotrophic Factor-Induced Oxidative Stress in the Pathophysiology of Diabetic Retinopathy.

    Science.gov (United States)

    Behl, Tapan; Kotwani, Anita

    2017-04-01

    Brain-derived neurotrophic factor (BDNF), a member of neurotrophin growth factor family, physiologically mediates induction of neurogenesis and neuronal differentiation, promotes neuronal growth and survival and maintains synaptic plasticity and neuronal interconnections. Unlike the central nervous system, its secretion in the peripheral nervous system occurs in an activity-dependent manner. BDNF improves neuronal mortality, growth, differentiation and maintenance. It also provides neuroprotection against several noxious stimuli, thereby preventing neuronal damage during pathologic conditions. However, in diabetic retinopathy (a neuromicrovascular disorder involving immense neuronal degeneration), BDNF fails to provide enough neuroprotection against oxidative stress-induced retinal neuronal apoptosis. This review describes the prime reasons for the downregulation of BDNF-mediated neuroprotective actions during hyperglycemia, which renders retinal neurons vulnerable to damaging stimuli, leading to diabetic retinopathy. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  14. Resolvin D1 inhibits inflammatory response in STZ-induced diabetic retinopathy rats: Possible involvement of NLRP3 inflammasome and NF-κB signaling pathway.

    Science.gov (United States)

    Yin, Yizhou; Chen, Fei; Wang, Wenyan; Wang, Han; Zhang, Xuedong

    2017-01-01

    To investigate the effect of resolvin D1 (RvD1) on the Nod-like receptor family pyrin domain-containing (NLRP3) inflammasome and the nuclear factor-kappa beta (NF-κB) pathway in streptozotocin (STZ)-induced diabetic retinopathy in rats. Ninety-six male rats were divided into four groups: control, STZ, RvD1, and vehicle. The rats with diabetic retinopathy induced by STZ in the RvD1 and vehicle groups were given an intravitreal injection of RvD1 (1,000 ng/kg) or the same dosage of vehicle, respectively. All rats were euthanized 7 days following treatment. Hematoxylin and eosin staining was used to observe the pathological changes in the retinal tissues. The location and expression of the NLRP3 inflammasome components, including NLRP3, caspase-associated recruitment domain (ASC), and caspase-1, in the retinas were detected using immunohistochemistry, real-time PCR, and western blot, respectively. Retinal homogenate of rats were collected for the detection of the downstream molecules interleukin 1 beta (IL-1β) and IL-18 of the NLRP3 inflammasome with enzyme-linked immunosorbent assay kits. The levels of NLRP3, ASC, cleaved caspase-1, IL-1β, and IL-18 were upregulated in the retinas of the STZ-induced diabetic rats; however, these changes were partially inhibited by the RvD1 treatment. Furthermore, the administration of RvD1 suppressed activation of NF-kB, which was upregulated in STZ-induced diabetic retinopathy. RvD1 plays a protective role in STZ-induced diabetic retinopathy by inhibiting the level of activation of the NLRP3 inflammasome and associated cytokine production, suggesting targeting of this pathway might be an effective strategy in treatment of diabetic retinopathy.

  15. Clinical features of radiation retinopathy

    International Nuclear Information System (INIS)

    Tabuchi, Shoko; Oda, Itsuo; Okawa, Tomohiko

    1977-01-01

    The clinical features of 25 cases with radiation retinopathy are described. Retinopathy was induced following therapeutic irradiation of paraobital malignancies with megavoltage Linac x-ray of 3,000 rads or more. Retinal vessels, particularly the proximal portion of retinal arteries, seemed to be the primary site of damage due to radiation. According to the type of lesion and dosage, fundus features simulated papillitis, retinal angiosclerosis, or hard exudates due to capillary obliteration. Acute obstruction of the central retinal artery and ischemic optic neuropathy could result from heavy irradiation of over 5,000 rads. (Evans, J.)

  16. The TetO rat as a new translational model for type 2 diabetic retinopathy by inducible insulin receptor knockdown.

    Science.gov (United States)

    Reichhart, Nadine; Crespo-Garcia, Sergio; Haase, Nadine; Golic, Michaela; Skosyrski, Sergej; Rübsam, Anne; Herrspiegel, Christina; Kociok, Norbert; Alenina, Natalia; Bader, Michael; Dechend, Ralf; Strauss, Olaf; Joussen, Antonia M

    2017-01-01

    Although the renin-angiotensin system plays an important role in the progression of diabetic retinopathy, its influence therein has not been systematically evaluated. Here we test the suitability of a new translational model of diabetic retinopathy, the TetO rat, for addressing the role of angiotensin-II receptor 1 (AT1) blockade in experimental diabetic retinopathy. Diabetes was induced by tetracycline-inducible small hairpin RNA (shRNA) knockdown of the insulin receptor in rats, generating TetO rats. Systemic treatment consisted of an AT1 blocker (ARB) at the onset of diabetes, following which, 4-5 weeks later the retina was analysed in vivo and ex vivo. Retinal function was assessed by Ganzfeld electroretinography (ERG). Retinal vessels in TetO rats showed differences in vessel calibre, together with gliosis. The total number and the proportion of activated mononuclear phagocytes was increased. TetO rats presented with loss of retinal ganglion cells (RGC) and ERG indicated photoreceptor malfunction. Both the inner and outer blood-retina barriers were affected. The ARB treated group showed reduced gliosis and an overall amelioration of retinal function, alongside RGC recovery, whilst no statistically significant differences in vascular and inflammatory features were detected. The TetO rat represents a promising translational model for the early neurovascular changes associated with type 2 diabetic retinopathy. ARB treatment had an effect on the neuronal component of the retina but not on the vasculature.

  17. Retinopathy secondary to radiation therapy for squamous cell carcinoma

    International Nuclear Information System (INIS)

    Groomer, A.E.; Gutwein, D.E.

    1989-01-01

    This report discusses a case of radiotherapy-induced retinopathy following treatment of squamous cell carcinoma. Treatment of the carcinoma with external beam radiotherapy to the supraorbital region and base of the skull was followed by the onset of retinopathy. The sensory retina, as well as other central nervous system tissues, is highly resistant to radiation damage; however, the retinal vasculature is extremely sensitive to radiation damage, producing a retinopathy that is characteristic of other vascular occlusive diseases. Management is discussed

  18. Diabetic Retinopathy

    Science.gov (United States)

    ... pregnancy may have rapid onset or worsening of diabetic retinopathy. Symptoms and Detection What are the symptoms of diabetic retinopathy and ... with diabetes protect their vision? Vision lost to diabetic retinopathy is ... However, early detection and treatment can reduce the risk of blindness ...

  19. [Diabetic retinopathy: pathogenesis and therapeutic implications].

    Science.gov (United States)

    Pelikánová, Terezie

    Diabetic retinopathy (DR) develops in patients with both type 1 and type 2 diabetes and is the major cause of vision loss and blindness in the working population. The main risk factor of DR is hyperglycemia accompanied by enhanced mitochondrial production of reactive oxygen species and oxidative stress, formation of advanced glycation end products (AGE) and hexosamines, increase in polyol metabolism of glucose. The severity of vascular injury depends on the individual genetic background and is modified by other epigenetic, metabolic and haemodynamic factors, including hypertension, dyslipidemia and oxidative stress. In diabetes, damage to the retina occurs in the vasculature (endothelial cells and pericytes), neurons and glia, pigment epithelial cells and infiltrating immunocompetent cells: monocytes, granulocytes, lymfocytes. These activated cells change the production pattern of a number of mediators such as growth factors, proinflammatory cytokines, vasoactive molecules, coagulation factors and adhesion molecules resulting in increased blood flow, increased capillary permeability, proliferation of extracellular matrix and thickening of basal membranes, altered cell turnover (apoptosis, proliferation, hypertrophy), procoagulant and proaggregant pattern, and finally in angiogenesis and tissue remodelling. Brain, liver, adipose tissue, GUT, skeletal muscle and other tissues could be another source of mediators. Therapeutic approaches used for patients with or at risk for diabetic retinopathy include drug therapy to reduce modifiable risk factors, laser photocoagulation, intravitreous administration of anti-VEGF agents/steroids and intraocular surgery. Screening plays an important role in early detection and intervention to prevent the progression of diabetic retinopathy. Described insights into pathophysiological mechanisms responsible for DR, could help in the development of more targeted approach for prevention and treatment of diabetic retinopathy. anti

  20. Decompression Retinopathy after ExPRESS Shunt Implantation for Steroid-Induced Ocular Hypertension: A Case Report

    Directory of Open Access Journals (Sweden)

    Khawla Abu Samra

    2011-01-01

    Full Text Available Purpose. To present a unique case of decompression retinopathy after the implantation of ExPRESS drainage device. Method. A 25-year-old female patient underwent implantation of ExPRESS drainage device in the left eye for the management of steroid-induced ocular hypertension. Results. On the postoperative day one, best-corrected visual acuity in the left eye was 20/50. Fundus examination revealed diffuse intraretinal hemorrhages, some white-centered, throughout the retina. There was also marked tortuosity to the retinal vasculature and no evidence of choroidal effusion. Intravenous fluorescein angiography and indocyanine green did not contribute to the aetiopathogenesis. Conclusion. Decompression retinopathy can occur following the implantation of ExPRESS drainage device. It is very important to be aware of this complication in patients with relatively high intraocular pressure who is planned for filtration surgery, including the ExPRESS implant.

  1. Pregnancy-induced sight-threatening diabetic retinopathy in women with Type 1 diabetes

    DEFF Research Database (Denmark)

    Vestgaard, Marianne; Nielsen, Lene Ringholm; Laugesen, C.S.

    2010-01-01

    To determine the progression of diabetic retinopathy in pregnant women with diabetes offered tight glycaemic and blood pressure control.......To determine the progression of diabetic retinopathy in pregnant women with diabetes offered tight glycaemic and blood pressure control....

  2. Advances in understanding and management of retinopathy of prematurity.

    Science.gov (United States)

    Hartnett, Mary Elizabeth

    The understanding, diagnosis, and treatment of retinopathy of prematurity have changed in the 70 years since the original description of retrolental fibroplasia associated with high oxygenation. It is now recognized that retinopathy of prematurity differs in appearance worldwide and as ever smaller and younger premature infants survive. New methods are being evaluated to image the retina, diagnose severe retinopathy of prematurity, and determine windows of time for treatment to save eyes and improve visual and neural outcomes. New treatments to promote physiologic retinal vascular development, vascular repair, and inhibit vasoproliferation by regulating proteins involved in vascular endothelial growth factor, insulin-like growth factor, or erythropoietin signaling. Reducing excessive oxidative/nitrosative stress and understanding progenitor cells and neurovascular and glial vascular interactions are being studied. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Catalase therapy corrects oxidative stress-induced pathophysiology in incipient diabetic retinopathy.

    Science.gov (United States)

    Giordano, Courtney R; Roberts, Robin; Krentz, Kendra A; Bissig, David; Talreja, Deepa; Kumar, Ashok; Terlecky, Stanley R; Berkowitz, Bruce A

    2015-05-01

    Preclinical studies have highlighted retinal oxidative stress in the pathogenesis of diabetic retinopathy. We evaluated whether a treatment designed to enhance cellular catalase reduces oxidative stress in retinal cells cultured in high glucose and in diabetic mice corrects an imaging biomarker responsive to antioxidant therapy (manganese-enhanced magnetic resonance imaging [MEMRI]). Human retinal Müller and pigment epithelial cells were chronically exposed to normal or high glucose levels and treated with a cell-penetrating derivative of the peroxisomal enzyme catalase (called CAT-SKL). Hydrogen peroxide (H2O2) levels were measured using a quantitative fluorescence-based assay. For in vivo studies, streptozotocin (STZ)-induced diabetic C57Bl/6 mice were treated subcutaneously once a week for 3 to 4 months with CAT-SKL; untreated age-matched nondiabetic controls and untreated diabetic mice also were studied. MEMRI was used to analytically assess the efficacy of CAT-SKL treatment on diabetes-evoked oxidative stress-related pathophysiology in vivo. Similar analyses were performed with difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase. After catalase transduction, high glucose-induced peroxide production was significantly lowered in both human retinal cell lines. In diabetic mice in vivo, subnormal intraretinal uptake of manganese was significantly improved by catalase supplementation. In addition, in the peroxisome-rich liver of treated mice catalase enzyme activity increased and oxidative damage (as measured by lipid peroxidation) declined. On the other hand, DFMO was largely without effect in these in vitro or in vivo assays. This proof-of-concept study raises the possibility that augmentation of catalase is a therapy for treating the retinal oxidative stress associated with diabetic retinopathy.

  4. Retinopathy of prematurity - from recognition of risk factors to treatment recommendations.

    Science.gov (United States)

    Fagerholm, Reija; Vesti, Eija

    Retinopathy of prematurity is a proliferative retinal disorder diagnosed exclusively in prematurely born infants. In retinopathy of prematurity, growth of the retinal vasculature is disturbed, leading to hypoxia-induced pathological changes typical of retinopathy of prematurity, in the worst case resulting in retinal detachment. The most typical risk factors predisposing to the disease include hyperoxemia, low levels of insulin-like growth factor 1 (IGF-I), and low birth weight in relation to weeks of pregnancy. Laser therapy of peripheral retina is the currently established form of treatment. Screening is applied in order to recognize the pathological changes in retinopathy of prematurity early enough.

  5. Changes in retinal venular oxygen saturation predict activity of proliferative diabetic retinopathy 3 months after panretinal photocoagulation.

    Science.gov (United States)

    Torp, Thomas Lee; Kawasaki, Ryo; Wong, Tien Yin; Peto, Tunde; Grauslund, Jakob

    2018-03-01

    Proliferative diabetic retinopathy (PDR) is a severe blinding condition. We investigated whether retinal metabolism, measured by retinal oximetry, may predict PDR activity after panretinal laser photocoagulation (PRP). We performed a prospective, interventional, clinical study of patients with treatment-naive PDR. Wide-field fluorescein angiography (OPTOS, Optomap) and global and focal retinal oximetry (Oxymap T1) were performed at baseline (BL), and 3 months (3M) after PRP. Angiographic findings were used to divide patients according to progression or non-progression of PDR after PRP. We evaluated differences in global and focal retinal oxygen saturation between patients with and without progression of PDR after PRP treatment. We included 45 eyes of 37 patients (median age and duration of diabetes were 51.6 and 20 years). Eyes with progression of PDR developed a higher retinal venous oxygen saturation than eyes with non-progression at 3M (global: +5.9% (95% CI -1.5 to 12.9), focal: +5.4%, (95% CI -4.1 to 14.8)). Likewise, progression of PDR was associated with a lower arteriovenular (AV) oxygen difference between BL and 3M (global: -6.1%, (95% CI -13.4 to -1.4), focal: -4.5% (95% CI -12.1 to 3.2)). In a multiple logistic regression model, increment in global retinal venular oxygen saturation (OR 1.30 per 1%-point increment, p=0.017) and decrement in AV oxygen saturation difference (OR 0.72 per 1%-point increment, p=0.016) at 3M independently predicted progression of PDR. Development of higher retinal venular and lower AV global oxygen saturation independently predicts progression of PDR despite standard PRP and might be a potential non-invasive marker of angiogenic disease activity. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Visual cycle modulation in neurovascular retinopathy.

    Science.gov (United States)

    Akula, James D; Hansen, Ronald M; Tzekov, Radouil; Favazza, Tara L; Vyhovsky, Tanya C; Benador, Ilan Y; Mocko, Julie A; McGee, David; Kubota, Ryo; Fulton, Anne B

    2010-08-01

    Rats with oxygen-induced retinopathy (OIR) model the pediatric retinal disease retinopathy of prematurity (ROP). Recent findings in OIR rats imply a causal role for the rods in the ROP disease process, although only experimental manipulation of rod function can establish this role conclusively. Accordingly, a visual cycle modulator (VCM) - with no known direct effect on retinal vasculature - was administered to "50/10 model" OIR Sprague-Dawley rats to test the hypotheses that it would 1) alter rod function and 2) consequently alter vascular outcome. Four litters of pups (N=46) were studied. For two weeks, beginning on postnatal day (P) 7, the first and fourth litters were administered 6 mg kg(-1) N-retinylacetamide (the VCM) intraperitoneally; the second and third litters received vehicle (DMSO) alone. Following a longitudinal design, retinal function was assessed by electroretinography (ERG) and the status of the retinal vessels was monitored using computerized fundus photograph analysis. Rod photoreceptor and post-receptor response amplitudes were significantly higher in VCM-treated than in vehicle-treated rats; deactivation of phototransduction was also significantly more rapid. Notably, the arterioles of VCM-treated rats showed significantly greater recovery from OIR. Presuming that the VCM did not directly affect the retinal vessels, a causal role for the neural retina - particularly the rod photoreceptors - in OIR was confirmed. There was no evidence of negative alteration of photoreceptor function consequent to VCM treatment. This finding implicates the rods as a possible therapeutic target in neurovascular diseases such as ROP. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Role of endoplasmic reticulum stress in 12/15-lipoxygenase-induced retinal microvascular dysfunction in a mouse model of diabetic retinopathy.

    Science.gov (United States)

    Elmasry, Khaled; Ibrahim, Ahmed S; Saleh, Heba; Elsherbiny, Nehal; Elshafey, Sally; Hussein, Khaled A; Al-Shabrawey, Mohamed

    2018-05-01

    Our earlier studies have established the role of 12/15-lipoxygenase (LO) in mediating the inflammatory reaction in diabetic retinopathy. However, the exact mechanism is still unclear. The goal of the current study was to identify the potential role of endoplasmic reticulum (ER) stress as a major cellular stress response in the 12/15-LO-induced retinal changes in diabetic retinopathy. We used in vivo and in vitro approaches. For in vivo studies, experimental diabetes was induced in wild-type (WT) mice and 12/15-Lo (also known as Alox15) knockout mice (12/15-Lo -/- ); ER stress was then evaluated after 12-14 weeks of diabetes. We also tested the effect of intravitreal injection of 12-hydroxyeicosatetraenoic acid (HETE) on retinal ER stress in WT mice and in mice lacking the catalytic subunit of NADPH oxidase, encoded by Nox2 (also known as Cybb) (Nox2 -/- mice). In vitro studies were performed using human retinal endothelial cells (HRECs) treated with 15-HETE (0.1 μmol/l) or vehicle, with or without ER stress or NADPH oxidase inhibitors. This was followed by evaluation of ER stress response, NADPH oxidase expression/activity and the levels of phosphorylated vascular endothelial growth factor receptor-2 (p-VEGFR2) by western blotting and immunoprecipitation assays. Moreover, real-time imaging of intracellular calcium (Ca 2+ ) release in HRECs treated with or without 15-HETE was performed using confocal microscopy. Deletion of 12/15-Lo significantly attenuated diabetes-induced ER stress in mouse retina. In vitro, 15-HETE upregulated ER stress markers such as phosphorylated RNA-dependent protein kinase-like ER-regulated kinase (p-PERK), activating transcription factor 6 (ATF6) and protein disulfide isomerase (PDI) in HRECs. Inhibition of ER stress reduced 15-HETE-induced-leucocyte adhesion, VEGFR2 phosphorylation and NADPH oxidase expression/activity. However, inhibition of NADPH oxidase or deletion of Nox2 had no effect on ER stress induced by the 12/15-LO

  8. Expression and significance of HIF-1α and VEGF in rats with diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Hong-Tao Yan; Guan-Fang Su

    2014-01-01

    Objective:To investigate the expression of hypoxia inducible factor-1α(HIF-1α) and vascular endothelial growth factor(VEGF) in diabetic retinopathy(DR) rats and its effect on theDR occurrence and development.Methods:A total of120SD rats were randomly divided into trial group and control group with60 in each.STZi.p. was used in the trial group to establish theDM model, citrate buffer salt of same amount was usedi.p. to the control group.1,3 and6 months after injection, respective20 rats were sacrificed in each group to observe expression ofHIF-1α andVEGF in the rat retina tissue at different time points.Results:Expression ofHIF-1α andVEGF were negative in the control group; expression ofHIF-1α andVEGF protein in retinal tissue were weak after1 month ofDR mold formation.It showed progressive enhancement along with the progression in different organizations, differences between groups were significant (P<0.05).Conclusions:Expressions ofHIF-1α andVEGF were correlated with disease progression in early diabetic retinopathy.Retinal oxygen can induce over-expression ofHIF-1α andVEGF.It shows thatHIF-1α andVEGF play an important role in the pathogenesis ofDR.

  9. Ultrastructure of neurovascular changes in human diabetic retinopathy.

    Science.gov (United States)

    Fehér, János; Taurone, Samanta; Spoletini, Marialuisa; Biró, Zsolt; Varsányi, Balázs; Scuderi, Gianluca; Orlando, Maria Patrizia; Turchetta, Rosaria; Micera, Alessandra; Artico, Marco

    2018-01-01

    The previous concept regarding diabetic retinopathy assigned a primary role to hyperglycemia-induced microvascular alterations, while neuronal and glial abnormalities were considered to be secondary to either ischemia or exudation. The aim of this study was to reveal the potential role of neuronal and glial cells in initial and advanced alterations of the retinopathy in human type 2 diabetes. Electron microscopy and histochemical studies were performed on 38 surgically removed human eyes (28 obtained from diabetic patients and 10 from non-diabetic patients). Morphometric analysis of basement membrane material and lipids was performed. An accumulation of metabolic by-products was found in the capillary wall with aging: this aspect was significantly more pronounced in diabetics. Müller glial cells were found to contribute to alterations of the capillary wall and to occlusion, as well as to the development of proliferative retinopathy and cystoid degeneration of the retina. Our results showed morphological evidence regarding the role of neuronal and glial cells in the pathology of diabetic retinopathy, prior and in addition to microangiopathy. These morphological findings support a neurovascular pathogenesis at the origin of diabetic retinopathy, thus the current treatment approach should be completed by neuroprotective measures.

  10. Noninvasive Retinal Markers in Diabetic Retinopathy: Advancing from Bench towards Bedside

    Directory of Open Access Journals (Sweden)

    Søren Leer Blindbæk

    2017-01-01

    Full Text Available The retinal vascular system is the only part of the human body available for direct, in vivo inspection. Noninvasive retinal markers are important to identity patients in risk of sight-threatening diabetic retinopathy. Studies have correlated structural features like retinal vascular caliber and fractals with micro- and macrovascular dysfunction in diabetes. Likewise, the retinal metabolism can be evaluated by retinal oximetry, and higher retinal venular oxygen saturation has been demonstrated in patients with diabetic retinopathy. So far, most studies have been cross-sectional, but these can only disclose associations and are not able to separate cause from effect or to establish the predictive value of retinal vascular dysfunction with respect to long-term complications. Likewise, retinal markers have not been investigated as markers of treatment outcome in patients with proliferative diabetic retinopathy and diabetic macular edema. The Department of Ophthalmology at Odense University Hospital, Denmark, has a strong tradition of studying the retinal microvasculature in diabetic retinopathy. In the present paper, we demonstrate the importance of the retinal vasculature not only as predictors of long-term microvasculopathy but also as markers of treatment outcome in sight-threatening diabetic retinopathy in well-established population-based cohorts of patients with diabetes.

  11. Noninvasive Retinal Markers in Diabetic Retinopathy: Advancing from Bench towards Bedside

    Science.gov (United States)

    Blindbæk, Søren Leer; Torp, Thomas Lee; Lundberg, Kristian; Soelberg, Kerstin; Vergmann, Anna Stage; Poulsen, Christina Døfler; Frydkjaer-Olsen, Ulrik; Broe, Rebecca; Rasmussen, Malin Lundberg; Wied, Jimmi; Lind, Majbrit; Vestergaard, Anders Højslet; Peto, Tunde

    2017-01-01

    The retinal vascular system is the only part of the human body available for direct, in vivo inspection. Noninvasive retinal markers are important to identity patients in risk of sight-threatening diabetic retinopathy. Studies have correlated structural features like retinal vascular caliber and fractals with micro- and macrovascular dysfunction in diabetes. Likewise, the retinal metabolism can be evaluated by retinal oximetry, and higher retinal venular oxygen saturation has been demonstrated in patients with diabetic retinopathy. So far, most studies have been cross-sectional, but these can only disclose associations and are not able to separate cause from effect or to establish the predictive value of retinal vascular dysfunction with respect to long-term complications. Likewise, retinal markers have not been investigated as markers of treatment outcome in patients with proliferative diabetic retinopathy and diabetic macular edema. The Department of Ophthalmology at Odense University Hospital, Denmark, has a strong tradition of studying the retinal microvasculature in diabetic retinopathy. In the present paper, we demonstrate the importance of the retinal vasculature not only as predictors of long-term microvasculopathy but also as markers of treatment outcome in sight-threatening diabetic retinopathy in well-established population-based cohorts of patients with diabetes. PMID:28491870

  12. Bevacizumab treatment for retinopathy of prematurity in South Africa

    African Journals Online (AJOL)

    ROP in the developing world. Retinopathy of prematurity (ROP) is a growing problem in South. Africa (SA), as it is in many parts of the developing world. The so-called 'third epidemic' of ROP is caused by a combination of high preterm birth rates, relatively good infant survival and inadequate oxygen monitoring in neonatal ...

  13. The progress of prophylactic treatment in retinopathy of prematurity

    Science.gov (United States)

    Zhang, Hong-Bing; Wang, Xiao-Dong; Xu, Kun; Li, Xiao-Gang

    2018-01-01

    Retinopathy of prematurity (ROP) is a retinal vascular disorder frequently found in premature infants. Different therapeutic strategies have been developed to treat ROP. However, there are still many children with ROP suffering by severe limitations in vision or even blindness. Recently, ROP has been suggested to be caused by abnormal development of the retinal vasculature, but not simply resulted by retinal neovascularization which takes about 4 to 6wk after birth in premature infants. Thus, instead of focusing on how to reduce retinal neovascularization, understanding the pathological changes and mechanisms that occur prior to retinal neovascularization is meaningful, which may lead to identify novel target(s) for the development of novel strategy to promote the healthy growth of retinal blood vessels rather than passively waiting for the appearance of retinal neovascularization and removing it by force. In this review, we discussed recent studies about, 1) the pathogenesis prior to retinal neovascularization in oxygen-induced retinopathy (OIR; a ROP in animal model) and in premature infants with ROP; 2) the preclinical and clinical research on preventive treatment of early OIR and ROP. We will not only highlight the importance of the mechanisms and signalling pathways in regulating early stage of ROP but also will provide guidance for actively exploring novel mechanisms and discovering novel treatments for early phase OIR and ROP prior to retinal neovascularization in the future. PMID:29862189

  14. What Is Diabetic Retinopathy?

    Science.gov (United States)

    ... Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus On Pediatric Ophthalmology ... Retinopathy Diagnosis Diabetic Retinopathy Treatment Proliferative Diabetic Retinopathy Vision Simulator Non-Proliferative Diabetic ...

  15. Asymmetric severity of diabetic retinopathy in Waardenburg syndrome

    Directory of Open Access Journals (Sweden)

    Kashima T

    2011-12-01

    Full Text Available Tomoyuki Kashima, Hideo Akiyama, Shoji KishiDepartment of Ophthalmology, Gunma University School of Medicine, Gunma 371-8511, JapanAbstract: A 30-year-old female patient was referred to our institution due to vitreous hemorrhage. Best corrected visual acuity of her right and left eyes at her initial visit was 10/20 and 20/20, respectively. Although hypochromic iris was observed in the superior iris between the 10 and 2 o’clock positions in her right eye, her entire left eye exhibited hypochromic iris. Hypopigmentation of the fundus was seen in the superior part of her right eye. This eye also had a huge neovascularization on the optic disc that was 7 discs in diameter. Conversely, her left fundi showed hypopigmentation of the fundus in the entire region of the left eye, and dot hemorrhages were observed all over the left fundi, although no neovascularization could be seen microscopically. Fluorescein angiography showed a huge neovascularization in the right eye and a tiny neovascularization in the left eye. Gene analysis revealed the presence of the PAX3 gene homeobox domain mutation, which led to her being diagnosed as Waardenburg syndrome type 1. Magnetic resonance angiography showed there was no obstructive region at either of the internal carotid arteries and ophthalmic arteries. The severity of the diabetic retinopathy appeared to be correlated with the degree of hypopigmentation in the posterior fundus. We speculate that hypopigmentation of the fundus in Waardenburg syndrome may be responsible for the reduction in retinal metabolism, which led to a reduction in oxygen consumption and prevented further aggravation of the diabetic retinopathy. Only laser treatments using short wavelengths was effective in this case. While the extinction coefficient for hemoglobin when using green light is higher than when using yellow light, the differences between these wavelengths tend to disappear when oxygenated hemoglobin is present. To the best of

  16. Determining diabetic retinopathy screening interval based on time from no retinopathy to laser therapy.

    Science.gov (United States)

    Hughes, Daniel; Nair, Sunil; Harvey, John N

    2017-12-01

    Objectives To determine the necessary screening interval for retinopathy in diabetic patients with no retinopathy based on time to laser therapy and to assess long-term visual outcome following screening. Methods In a population-based community screening programme in North Wales, 2917 patients were followed until death or for approximately 12 years. At screening, 2493 had no retinopathy; 424 had mostly minor degrees of non-proliferative retinopathy. Data on timing of first laser therapy and visual outcome following screening were obtained from local hospitals and ophthalmology units. Results Survival analysis showed that very few of the no retinopathy at screening group required laser therapy in the early years compared with the non-proliferative retinopathy group ( p retinopathy at screening group required laser therapy, and at three years 0.2% (cumulative), lower rates of treatment than have been suggested by analyses of sight-threatening retinopathy determined photographically. At follow-up (mean 7.8 ± 4.6 years), mild to moderate visual impairment in one or both eyes due to diabetic retinopathy was more common in those with retinopathy at screening (26% vs. 5%, p diabetes occurred in only 1 in 1000. Conclusions Optimum screening intervals should be determined from time to active treatment. Based on requirement for laser therapy, the screening interval for diabetic patients with no retinopathy can be extended to two to three years. Patients who attend for retinal screening and treatment who have no or non-proliferative retinopathy now have a very low risk of eventual blindness from diabetes.

  17. Factors given by birth and oxygenotherapy in relation to development of retinopathy of prematurity

    OpenAIRE

    Olujić Maja; Oros Ana; Bregun-Doronjski Alekandra; Velisavljev-Filipović Gordana

    2012-01-01

    Introduction. Retinopathy of prematurity is a disease of the eye which affects the blood vessels of the retina and represents the most important cause of blindness and low vision in children worldwide. There are many risk factors given by birth and parameters of general health status that may influence this disease. The aim of this study was to investigate the significance of the factors given by birth and use of oxygen in relation to the development of premature retinopathy. Material a...

  18. Biomarkers in Diabetic Retinopathy.

    Science.gov (United States)

    Jenkins, Alicia J; Joglekar, Mugdha V; Hardikar, Anandwardhan A; Keech, Anthony C; O'Neal, David N; Januszewski, Andrzej S

    2015-01-01

    There is a global diabetes epidemic correlating with an increase in obesity. This coincidence may lead to a rise in the prevalence of type 2 diabetes. There is also an as yet unexplained increase in the incidence of type 1 diabetes, which is not related to adiposity. Whilst improved diabetes care has substantially improved diabetes outcomes, the disease remains a common cause of working age adult-onset blindness. Diabetic retinopathy is the most frequently occurring complication of diabetes; it is greatly feared by many diabetes patients. There are multiple risk factors and markers for the onset and progression of diabetic retinopathy, yet residual risk remains. Screening for diabetic retinopathy is recommended to facilitate early detection and treatment. Common biomarkers of diabetic retinopathy and its risk in clinical practice today relate to the visualization of the retinal vasculature and measures of glycemia, lipids, blood pressure, body weight, smoking, and pregnancy status. Greater knowledge of novel biomarkers and mediators of diabetic retinopathy, such as those related to inflammation and angiogenesis, has contributed to the development of additional therapeutics, in particular for late-stage retinopathy, including intra-ocular corticosteroids and intravitreal vascular endothelial growth factor inhibitors ('anti-VEGFs') agents. Unfortunately, in spite of a range of treatments (including laser photocoagulation, intraocular steroids, and anti-VEGF agents, and more recently oral fenofibrate, a PPAR-alpha agonist lipid-lowering drug), many patients with diabetic retinopathy do not respond well to current therapeutics. Therefore, more effective treatments for diabetic retinopathy are necessary. New analytical techniques, in particular those related to molecular markers, are accelerating progress in diabetic retinopathy research. Given the increasing incidence and prevalence of diabetes, and the limited capacity of healthcare systems to screen and treat

  19. Placental growth factor and its potential role in diabetic retinopathy and other ocular neovascular diseases.

    Science.gov (United States)

    Nguyen, Quan Dong; De Falco, Sandro; Behar-Cohen, Francine; Lam, Wai-Ching; Li, Xuri; Reichhart, Nadine; Ricci, Federico; Pluim, Jennifer; Li, William W

    2018-02-01

    The role of vascular endothelial growth factor (VEGF), including in retinal vascular diseases, has been well studied, and pharmacological blockade of VEGF is the gold standard of treatment for neovascular age-related macular degeneration, retinal vein occlusion and diabetic macular oedema. Placental growth factor (PGF, previously known as PlGF), a homologue of VEGF, is a multifunctional peptide associated with angiogenesis-dependent pathologies in the eye and non-ocular conditions. Animal studies using genetic modification and pharmacological treatment have demonstrated a mechanistic role for PGF in pathological angiogenesis. Inhibition decreases neovascularization and microvascular abnormalities across different models, including oxygen-induced retinopathy, laser-induced choroidal neovascularization and in diabetic mice exhibiting retinopathies. High levels of PGF have been found in the vitreous of patients with diabetic retinopathy. Despite these strong animal data, the exact role of PGF in pathological angiogenesis in retinal vascular diseases remains to be defined, and the benefits of PGF-specific inhibition in humans with retinal neovascular diseases and macular oedema remain controversial. Comparative effectiveness research studies in patients with diabetic retinal disease have shown that treatment that inhibits both VEGF and PGF may provide superior outcomes in certain patients compared with treatment that inhibits only VEGF. This review summarizes current knowledge of PGF, including its relationship to VEGF and its role in pathological angiogenesis in retinal diseases, and identifies some key unanswered questions about PGF that can serve as a pathway for future basic, translational and clinical research. © 2016 The Authors. Acta Ophthalmologica published by John Wiley & Sons Ltd on behalf of Acta Ophthalmologica Scandinavica Foundation and European Association for Vision & Eye Research.

  20. Delayed progression of diabetic cataractogenesis and retinopathy by Litchi chinensis in STZ-induced diabetic rats.

    Science.gov (United States)

    Kilari, Eswar Kumar; Putta, Swathi

    2017-03-01

    The study was carried out to evaluate the effect of the aqueous fruit pericarp extract of Litchi chinensis (APLC) on parameters which leads to diabetic cataractogenesis and retinopathy in the streptozotocin-induced diabetic rats. The objective of the study is to evaluate the APLC for in vivo antioxidant activity and its role in inhibiting the polyol pathway and formation of advanced glycation end products (AGEs). The diabetic animals were treated with L. chinensis for a period of 12 weeks. At the end of 12 weeks, the animals were killed and the biochemical pathways involved in the pathogenesis of cataract such as oxidative stress by protein content, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and polyolpathway by aldose reductase (AR) in lens homogenates, alterations in protein carbonyl content (PCO) and AGEs in both serum and lens the APLC-treated diabetic rats were compared against diabetic control rats. Cataract progression due to hyperglycemia was monitored by slit lamp bio microscope and classified into four stages. Fundoscope test and retinal histopathology were done for assessing retinopathy. Statistically significant reduction in glucose, and elevation of protein content, SOD, CAT, and GSH levels and decreased levels of AR and PCO in lens homogenate and significant reduction in AGEs serum and lens homogenate were observed. Slit lamp examination, fundoscope, and histopathology showed improvement in retinal changes in APLC-treated rats compared to diabetic control animals. The treatment with APLC found to delay the progression of diabetic cataractogenesis and retinopathy, which might be due to its antioxidant activity, because of the presence of active phytochemicals in APLC.

  1. The relation between oxygen saturation level and retionopathy of prematurity

    Directory of Open Access Journals (Sweden)

    Mohammad Gharavi Fard

    2016-03-01

    Full Text Available Introduction: Oxygen therapy used for preterm infant disease might be associated with oxygen toxicity or oxidative stress. The exact oxygen concentration to control and maintain the arterial oxygen saturation balance is not certainly clear. We aimed to compare the efficacy of higher or lower oxygen saturations on the development of severe retinopathy of prematurity which is a major cause of blindness in preterm neonates. Methods: PubMed was searched for obtaining the relevant articles. A total of seven articles were included after studying the titles, abstracts, and the full text of retrieved articles at initial search. Inclusion criteria were all the English language human clinical randomized controlled trials with no time limitation, which studied the efficacy of low versus high oxygen saturation measured by pulse oximetry in preterm infants.Result: It can be suggested that lower limits of oxygen saturations have higher efficacy at postmesetural age of ≤28 weeks in preterm neonates. This relation has been demonstrated in five large clinical trials including three Boost trials, COT, and Support.Discussion: Applying higher concentrations of oxygen supplementations at mesentural age ≥32 weeks reduced the development of retinopathy of prematurity. Lower concentrations of oxygen saturation decreased the incidence and the development of retinopathy of prematurity in preterm neonates while applied soon after the birth.Conclusions: Targeting levels of oxygen saturation in the low or high range should be performed cautiously with attention to the postmesentural age in preterm infants at the time of starting the procedures.

  2. Biomarkers in Diabetic Retinopathy

    Science.gov (United States)

    Jenkins, Alicia J.; Joglekar, Mugdha V.; Hardikar, Anandwardhan A.; Keech, Anthony C.; O'Neal, David N.; Januszewski, Andrzej S.

    2015-01-01

    There is a global diabetes epidemic correlating with an increase in obesity. This coincidence may lead to a rise in the prevalence of type 2 diabetes. There is also an as yet unexplained increase in the incidence of type 1 diabetes, which is not related to adiposity. Whilst improved diabetes care has substantially improved diabetes outcomes, the disease remains a common cause of working age adult-onset blindness. Diabetic retinopathy is the most frequently occurring complication of diabetes; it is greatly feared by many diabetes patients. There are multiple risk factors and markers for the onset and progression of diabetic retinopathy, yet residual risk remains. Screening for diabetic retinopathy is recommended to facilitate early detection and treatment. Common biomarkers of diabetic retinopathy and its risk in clinical practice today relate to the visualization of the retinal vasculature and measures of glycemia, lipids, blood pressure, body weight, smoking, and pregnancy status. Greater knowledge of novel biomarkers and mediators of diabetic retinopathy, such as those related to inflammation and angiogenesis, has contributed to the development of additional therapeutics, in particular for late-stage retinopathy, including intra-ocular corticosteroids and intravitreal vascular endothelial growth factor inhibitors ('anti-VEGFs') agents. Unfortunately, in spite of a range of treatments (including laser photocoagulation, intraocular steroids, and anti-VEGF agents, and more recently oral fenofibrate, a PPAR-alpha agonist lipid-lowering drug), many patients with diabetic retinopathy do not respond well to current therapeutics. Therefore, more effective treatments for diabetic retinopathy are necessary. New analytical techniques, in particular those related to molecular markers, are accelerating progress in diabetic retinopathy research. Given the increasing incidence and prevalence of diabetes, and the limited capacity of healthcare systems to screen and treat

  3. Human bone marrow mesenchymal stem cells for retinal vascular injury.

    Science.gov (United States)

    Wang, Jin-Da; An, Ying; Zhang, Jing-Shang; Wan, Xiu-Hua; Jonas, Jost B; Xu, Liang; Zhang, Wei

    2017-09-01

    To examine the potential of intravitreally implanted human bone marrow-derived mesenchymal stem cells (BMSCs) to affect vascular repair and the blood-retina barrier in mice and rats with oxygen-induced retinopathy, diabetic retinopathy or retinal ischaemia-reperfusion damage. Three study groups (oxygen-induced retinopathy group: 18 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received BMSCs injected intravitreally. Control groups (oxygen-induced retinopathy group: 12 C57BL/6J mice; diabetic retinopathy group: 15 rats; retinal ischaemia-reperfusion model: 18 rats) received an intravitreal injection of phosphate-buffered saline. We applied immunohistological techniques to measure retinal vascularization, spectroscopic measurements of intraretinally extravasated fluorescein-conjugated dextran to quantify the blood-retina barrier breakdown, and histomorphometry to assess retinal thickness and retinal ganglion cell count. In the oxygen-induced retinopathy model, the study group with intravitreally injected BMSCs as compared with the control group showed a significantly (p = 0.001) smaller area of retinal neovascularization. In the diabetic retinopathy model, study group and control group did not differ significantly in the amount of intraretinally extravasated dextran. In the retinal ischaemia-reperfusion model, on the 7th day after retina injury, the retina was significantly thicker in the study group than in the control group (p = 0.02), with no significant difference in the retinal ganglion cell count (p = 0.36). Intravitreally implanted human BMSCs were associated with a reduced retinal neovascularization in the oxygen-induced retinopathy model and with a potentially cell preserving effect in the retinal ischaemia-reperfusion model. Intravitreal BMSCs may be of potential interest for the therapy of retinal vascular disorders. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley

  4. Diabetic Retinopathy Analysis

    Directory of Open Access Journals (Sweden)

    R. Sivakumar

    2005-01-01

    Full Text Available Diabetic retinopathy is one of the common complications of diabetes. Unfortunately, in many cases the patient is not aware of any symptoms until it is too late for effective treatment. Through analysis of evoked potential response of the retina, the optical nerve, and the optical brain center, a way will be paved for early diagnosis of diabetic retinopathy and prognosis during the treatment process. In this paper, we present an artificial-neural-network-based method to classify diabetic retinopathy subjects according to changes in visual evoked potential spectral components and an anatomically realistic computer model of the human eye under normal and retinopathy conditions in a virtual environment using 3D Max Studio and Windows Movie Maker.

  5. Radiation retinopathy; Les retinopathies radio-induites

    Energy Technology Data Exchange (ETDEWEB)

    Lumbroso, L.; Desjardins, L. [Institut Curie, Serv. d' Ophtalmologie, 75 - Paris (France); Dendale, R.; Fourquet, A. [Institut Curie, Serv. de Radiotherapie, 75 - Paris (France)

    2002-09-01

    Radiation retinopathy is a retinal micro-angiopathy, observed after irradiation of the eye. It can rarely lead to neo-vascular glaucoma and enucleation due to pain. It is due to a progressive retinal capillary then vascular occlusion. Total irradiation dose, dose fraction, and surface of the irradiated retina seem to be strong predictive factors for radiation retinopathy. Patients who underwent an irradiation near the eye (skull base tumors, nasal and paranasal tumors, or brain tumors) should be followed by periodic ophthalmologic examination to detect and treat when necessary the non perfusion areas. (authors)

  6. Inhibition of retinopathy of prematurity in rat by intravitreal injection of sorafenib

    Directory of Open Access Journals (Sweden)

    Li-Li Tian

    2014-04-01

    Full Text Available AIM:To investigate the effect of intravitreal injection administered sorafenib, a multikinase inhibitor, in a rat model of oxygen-induced retinopathy (OIR.METHODS:Seven-day-old Sprague-Dawley rats (n=144 were randomly assigned to six groups. Group A received normal partial oxygen pressure and groups B, C, D, E and F were exposed to hyperoxia (75±2% from postnatal 7d (P7 to P12 to induce retinopathy of prematurity. The rats in groups C, D, E and F were received intravitreal injections of either vehicle (DMSO or sorafenib at P12 (5, 20 and 80 μg, respectively. Then they returned to normoxia after P12. The retinas were whole-mounted and imaged with a confocal microscopy. The vascular branching points were counted to quantify neovascularization at P17. Cross-sections of the retina were stained with hematoxylin and eosin (HE. The nuclei of new vessels breaking the internal limiting membrane were counted to quantify the proliferative neovascular response.RESULTS:The retinal vessel in groups B and C turned into tortuosity and a great deal of neovascularization were observed. Sorafenib-treated rats had significantly less neovascularization as compared with vehicle-treated and control rats in a dose dependent manner (P<0.05. The number of vascular branching points in A, B, C, D, E and F were 16.50±3.90, 37.44±6.47, 37.08±5.10, 30.80±6.85, 26.08±5.08 and 19.83±3.51, respectively. The number of the nuclei of retinal new vessel in A, B, C, D, E and F were 0.22±0.42, 35.66±4.70, 35.30±4.54, 27.30±4.28, 21.41±3.53, and 7.41±2.87, respectively. There were significant difference between each group (P<0.05 except groups B and C.CONCLUSION: In the rat OIR model, sorafenib could inhibit retinal neovascularization in a dose dependent manner.

  7. Delay in diabetic retinopathy screening increases the rate of detection of referable diabetic retinopathy.

    Science.gov (United States)

    Scanlon, P H; Aldington, S J; Stratton, I M

    2014-04-01

    To assess whether there is a relationship between delay in retinopathy screening after diagnosis of type 2 diabetes and level of retinopathy detected. Patients were referred from 88 primary care practices to an English National Health Service diabetic eye screening programme. Data for screened patients were extracted from the primary care databases using semi-automated data collection algorithms supplemented by validation processes. The programme uses two-field mydriatic digital photographs graded by a quality assured team. Data were available for 8183 screened patients with diabetes newly diagnosed in 2005, 2006 or 2007. Only 163 with type 1 diabetes were identified and were insufficient for analysis. Data were available for 8020 with newly diagnosed type 2 diabetes. Of these, 3569 were screened within 6 months, 2361 between 6 and 11 months, 1058 between 12 and 17 months, 366 between 18 and 23 months, 428 between 24 and 35 months, and 238 at 3 years or more after diagnosis. There were 5416 (67.5%) graded with no retinopathy, 1629 (20.3%) with background retinopathy in one eye, 753 (9.4%) with background retinopathy in both eyes and 222 (2.8%) had referable diabetic retinopathy. There was a significant trend (P = 0.0004) relating time from diagnosis to screening detecting worsening retinopathy. Of those screened within 6 months of diagnosis, 2.3% had referable retinopathy and, 3 years or more after diagnosis, 4.2% had referable retinopathy. The rate of detection of referable diabetic retinopathy is elevated in those who were not screened promptly after diagnosis of type 2 diabetes. © 2013 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.

  8. Asymmetric severity of diabetic retinopathy in Waardenburg syndrome.

    Science.gov (United States)

    Kashima, Tomoyuki; Akiyama, Hideo; Kishi, Shoji

    2011-01-01

    A 30-year-old female patient was referred to our institution due to vitreous hemorrhage. Best corrected visual acuity of her right and left eyes at her initial visit was 10/20 and 20/20, respectively. Although hypochromic iris was observed in the superior iris between the 10 and 2 o'clock positions in her right eye, her entire left eye exhibited hypochromic iris. Hypopigmentation of the fundus was seen in the superior part of her right eye. This eye also had a huge neovascularization on the optic disc that was 7 discs in diameter. Conversely, her left fundi showed hypopigmentation of the fundus in the entire region of the left eye, and dot hemorrhages were observed all over the left fundi, although no neovascularization could be seen microscopically. Fluorescein angiography showed a huge neovascularization in the right eye and a tiny neovascularization in the left eye. Gene analysis revealed the presence of the PAX3 gene homeobox domain mutation, which led to her being diagnosed as Waardenburg syndrome type 1. Magnetic resonance angiography showed there was no obstructive region at either of the internal carotid arteries and ophthalmic arteries. The severity of the diabetic retinopathy appeared to be correlated with the degree of hypopigmentation in the posterior fundus. We speculate that hypopigmentation of the fundus in Waardenburg syndrome may be responsible for the reduction in retinal metabolism, which led to a reduction in oxygen consumption and prevented further aggravation of the diabetic retinopathy. Only laser treatments using short wavelengths was effective in this case. While the extinction coefficient for hemoglobin when using green light is higher than when using yellow light, the differences between these wavelengths tend to disappear when oxygenated hemoglobin is present. To the best of the authors' knowledge, this is the first case report of a patient with Waardenburg syndrome and diabetic retinopathy.

  9. Proliferative retinopathy predicts nephropathy

    DEFF Research Database (Denmark)

    Karlberg, Charlotte; Falk, Christine; Green, Anders

    2012-01-01

    We wanted to examine proliferative retinopathy as a marker of incident nephropathy in a 25-year follow-up study of a population-based cohort of Danish type 1 diabetic patients and to examine cross-sectional associations between nephropathy and retinopathy in long-term surviving patients of the same...... cohort. All type 1 diabetic patients from Fyn County, Denmark, were identified as of 1 July 1973. One hundred and eighty four patients were examined in 1981-1982 (baseline) and in 2007-2008 (follow-up). The level of retinopathy was graded by ophthalmoscopy at baseline and nine-field digital colour fundus...... and proliferative retinopathy, respectively. In conclusion, proliferative retinopathy is an independent marker of long-term nephropathy in type 1 diabetes. Upcoming studies should examine whether these microvascular complications are also causally linked in type 1 diabetes....

  10. Role of altered coagulation-fibrinolytic system in the pathophysiology of diabetic retinopathy.

    Science.gov (United States)

    Behl, Tapan; Velpandian, Thirumurthy; Kotwani, Anita

    2017-05-01

    The implications of altered coagulation-fibrinolytic system in the pathophysiology of several vascular disorders, such as stroke and myocardial infarction, have been well researched upon and established. However, its role in the progression of diabetic retinopathy has not been explored much. Since a decade, it is known that hyperglycemia is associated with a hypercoagulated state and the various impairments it causes are well acknowledged as independent risk factors for the development of cardiovascular diseases. But recent studies suggest that the hypercoagulative state and diminished fibrinolytic responses might also alter retinal homeostasis and induce several deleterious molecular changes in retinal cells which aggravate the already existing hyperglycemia-induced pathological conditions and thereby lead to the progression of diabetic retinopathy. The major mediators of coagulation-fibrinolytic system whose concentration or activity get altered during hyperglycemia include fibrinogen, antithrombin-III (AT-III), plasminogen activator inhibitor-1 (PAI-1) and von Willebrand factor (vWF). Inhibiting the pathways by which these altered mediators get involved in the pathophysiology of diabetic retinopathy can serve as potential targets for the development of an adjuvant novel alternative therapy for diabetic retinopathy. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Hypertensive retinopathy (image)

    Science.gov (United States)

    ... retina from high blood pressure is called hypertensive retinopathy. It occurs as the existing high blood pressure ... flame hemorrhages and cotton wool spots. As hypertensive retinopathy progresses, hard exudates can appear around the macula ...

  12. Dissolved oxygen detection by galvanic displacement-induced

    Indian Academy of Sciences (India)

    Dissolved oxygen detection by galvanic displacement-induced graphene/silver nanocomposite ... dissolved oxygen (DO) detection based on a galvanic displacement synthesized reduced graphene oxide–silver nanoparticles ... Current Issue

  13. Predicted impact of extending the screening interval for diabetic retinopathy: the Scottish Diabetic Retinopathy Screening programme.

    Science.gov (United States)

    Looker, H C; Nyangoma, S O; Cromie, D T; Olson, J A; Leese, G P; Philip, S; Black, M W; Doig, J; Lee, N; Briggs, A; Hothersall, E J; Morris, A D; Lindsay, R S; McKnight, J A; Pearson, D W M; Sattar, N A; Wild, S H; McKeigue, P; Colhoun, H M

    2013-08-01

    The aim of our study was to identify subgroups of patients attending the Scottish Diabetic Retinopathy Screening (DRS) programme who might safely move from annual to two yearly retinopathy screening. This was a retrospective cohort study of screening data from the DRS programme collected between 2005 and 2011 for people aged ≥12 years with type 1 or type 2 diabetes in Scotland. We used hidden Markov models to calculate the probabilities of transitions to referable diabetic retinopathy (referable background or proliferative retinopathy) or referable maculopathy. The study included 155,114 individuals with no referable diabetic retinopathy or maculopathy at their first DRS examination and with one or more further DRS examinations. There were 11,275 incident cases of referable diabetic eye disease (9,204 referable maculopathy, 2,071 referable background or proliferative retinopathy). The observed transitions to referable background or proliferative retinopathy were lower for people with no visible retinopathy vs mild background retinopathy at their prior examination (respectively, 1.2% vs 8.1% for type 1 diabetes and 0.6% vs 5.1% for type 2 diabetes). The lowest probability for transitioning to referable background or proliferative retinopathy was among people with two consecutive screens showing no visible retinopathy, where the probability was <0.3% for type 1 and <0.2% for type 2 diabetes at 2 years. Transition rates to referable diabetic eye disease were lowest among people with type 2 diabetes and two consecutive screens showing no visible retinopathy. If such people had been offered two yearly screening the DRS service would have needed to screen 40% fewer people in 2009.

  14. Effect of doxycycline vs placebo on retinal function and diabetic retinopathy progression in patients with severe nonproliferative or non-high-risk proliferative diabetic retinopathy

    DEFF Research Database (Denmark)

    Scott, Ingrid U; Jackson, Gregory R; Quillen, David A

    2014-01-01

    IMPORTANCE: Inflammation may contribute to the pathogenesis of diabetic retinopathy (DR). OBJECTIVES: To investigate, in a proof-of-concept clinical trial, whether low-dose oral doxycycline monohydrate can (1) slow the deterioration of, or improve, retinal function or (2) induce regression or slow......: We conducted a randomized, double-masked, 24-month proof-of-concept clinical trial. Thirty patients (from hospital-based retina practices) with 1 or more eyes with severe NPDR or PDR less than Early Treatment Diabetic Retinopathy Study-defined high-risk PDR. INTERVENTIONS: Patients were randomized...... adaptation, visual acuity, and quality of life) and anatomic factors (Early Treatment Diabetic Retinopathy Study DR severity level, area of retinal thickening, central macular thickness, macular volume, and retinal vessel diameters). RESULTS: From baseline to month 24, mean FDP foveal sensitivity decreased...

  15. Metabolic Prosthesis for Oxygenation of Ischemic Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias [ORNL

    2009-01-01

    This communication discloses new ideas and preliminary results on the development of a "metabolic prosthesis" for local oxygenation of ischemic tissue under physiological neutral conditions. We report for the first time the selective electrolysis of physiological saline by repetitively pulsed charge-limited electrolysis for the production of oxygen and suppression of free chlorine. For example, using 800 A amplitude current pulses and <200 sec pulse durations, we demonstrated prompt oxygen production and delayed chlorine production at the surface of a shiny 0.85 mm diameter spherical platinum electrode. The data, interpreted in terms of the ionic structure of the electric double layer, suggest a strategy for in situ production of metabolic oxygen via a new class of "smart" prosthetic implants for dealing with ischemic disease such as diabetic retinopathy. We also present data indicating that drift of the local pH of the oxygenated environment can be held constant using a feedback-controlled three electrode electrolysis system that chooses anode and cathode pair based on pH data provided by local microsensors. The work is discussed in the context of diabetic retinopathy since surgical techniques for multielectrode prosthetic implants aimed at retinal degenerative diseases have been developed.

  16. Non-Proliferative Diabetic Retinopathy Vision Simulator

    Science.gov (United States)

    ... Oncology Oculoplastics/Orbit Refractive Management/Intervention Retina/Vitreous Uveitis Focus On Pediatric Ophthalmology ... Retinopathy Diagnosis Diabetic Retinopathy Treatment Proliferative Diabetic Retinopathy Vision Simulator Non-Proliferative Diabetic ...

  17. Role of VEGF-A in endothelial phenotypic shift in human diabetic retinopathy and VEGF-A-induced retinopathy in monkeys

    NARCIS (Netherlands)

    Hofman, P.; Blaauwgeers, H. G.; Vrensen, G. F.; Schlingemann, R. O.

    2001-01-01

    The endothelium-specific antigen PAL-E, associated with transport vesicles in non-barrier endothelium, is almost absent from barrier capillaries in the normal brain and retina. We have recently demonstrated that only leaking retinal capillaries in diabetic retinopathy (DR) in humans

  18. Preventing radiation retinopathy with hyperfractionation

    International Nuclear Information System (INIS)

    Monroe, Alan T.; Bhandare, Niranjan; Morris, Christopher G.; Mendenhall, William M.

    2005-01-01

    Purpose: The purpose of this study was to determine factors associated with the development of radiation retinopathy in a large series of patients with head-and-neck cancer. In particular, we addressed whether the use of hyperfractionated radiation therapy was effective in reducing the risk of retinopathy. Methods and materials: One hundred eighty-six patients received a significant dose to the retina as part of curative radiotherapy. Primary sites included: nasopharynx, 46; paranasal sinus, 64; nasal cavity, 69; and palate, 7. Prescription doses varied depending on primary site and histology. Hyperfractionated (twice-daily) radiation was delivered to 42% of the patients in this study, typically at 1.10 to 1.20 Gy per fraction. The remainder were treated once-daily. Retinal doses were determined from computerized dosimetry plans when available. For all other patients, retinal doses were retrospectively calculated using reconstructed off-axis dosimetry taken from contours through the center of the globes. Retinal dose was defined as the minimum dose received by at least 25% of the globe. The median retinal dose was 56.85 Gy. Patients were followed for a median of 7.6 years. Results: Thirty-one eyes in 30 patients developed radiation retinopathy, resulting in monocular blindness in 25, bilateral blindness in 1, and decreased visual acuity in 4. The median time to the diagnosis of retinopathy was 2.6 years (range, 11 months to 5.3 years). The actuarial incidence of developing radiation retinopathy was 20% at both 5 and 10 years. The incidence of developing ipsilateral blindness due to retinopathy was 16% at 5 years and 17% at 10 years. Site-specific incidences varied considerably, with ethmoid sinus (9 of 25, 36%), nasal cavity (13 of 69, 19%), and maxillary sinus (6 of 35, 17%) being the most common sites associated with radiation retinopathy. Three of 72 patients (4%) receiving retinal doses less than 50 Gy developed retinopathy. Higher retinal doses resulted in a

  19. Lipasin, a biomarker of diabetic retinopathy.

    Science.gov (United States)

    Fang, Chen; Huang, Yun; Guo, Heming; Gao, Yan; Ji, Xiaoyan; Hu, Ji

    2016-05-01

    The present study recruited 74 participants with type 2 diabetes, among which 23 had retinopathy. Those with retinopathy had a longer duration of diabetes and higher levels of lipasin compared with those without retinopathy. Logistic regression revealed that lipasin was independently and significantly associated with retinopathy even after adjustments for confounders. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Role of endoplasmic reticulum stress in the loss of retinal ganglion cells in diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Liping Yang; Lemeng Wu; Dongmei Wang; Ying Li; Hongliang Dou; Mark OMTso; Zhizhong Ma

    2013-01-01

    Endoplasmic reticulum stress is closely involved in the early stage of diabetic retinopathy. In the present study, a streptozotocin-induced diabetic animal model was given an intraperitoneal injection of tauroursodeoxycholic acid. Results from immunofluorescent co-localization experiments showed that both caspase-12 protein and c-Jun N-terminal kinase 1 phosphorylation levels significantly in-creased, which was associated with retinal ganglion celldeath in diabetic retinas. The C/ERB ho-mologous protein pathway directly contributed to glial reactivity, and was subsequently responsible for neuronal loss and vascular abnormalities in diabetic retinopathy. Our experimental findings in-dicate that endoplasmic reticulum stress plays an important role in diabetes-induced retinal neu-ronal loss and vascular abnormalities, and that inhibiting the activation of the endoplasmic reticulum stress pathway provides effective protection against diabetic retinopathy.

  1. A case of early-onset radiation retinopathy

    International Nuclear Information System (INIS)

    Sato, Yoko; Den, Seika; Shimizu, Kazuhiro; Ikeda, Tsunehiko

    2001-01-01

    We encountered a 27-year-old male early caused by radiation retinopathy five months after radiotherapy (51 Gy) for astrocytoma. The retinopathy was the proliferative retinopathy, with several dot and blot hemorrhages, hard and soft exudate, increased capillary permeability, macula edema and avasucular areas. So it was treated with panretial photocoagulation like diabetic retinopathy. Now hemorrhage, exudate, edema and avascular areas were improved. Photocoagulation treatment is effective to stop the progression of radiation retinopathy. Radiation retinopathy is sometimes early caused, therefore long-term follow up is recommended on starting radiotherapy. (author)

  2. A case of early-onset radiation retinopathy

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yoko; Den, Seika; Shimizu, Kazuhiro; Ikeda, Tsunehiko [Osaka Medical Coll., Takatsuki (Japan)

    2001-12-01

    We encountered a 27-year-old male early caused by radiation retinopathy five months after radiotherapy (51 Gy) for astrocytoma. The retinopathy was the proliferative retinopathy, with several dot and blot hemorrhages, hard and soft exudate, increased capillary permeability, macula edema and avasucular areas. So it was treated with panretial photocoagulation like diabetic retinopathy. Now hemorrhage, exudate, edema and avascular areas were improved. Photocoagulation treatment is effective to stop the progression of radiation retinopathy. Radiation retinopathy is sometimes early caused, therefore long-term follow up is recommended on starting radiotherapy. (author)

  3. Oxidative stress in diabetic patients with retinopathy | Kundu ...

    African Journals Online (AJOL)

    Background: Diabetes mellitus (DM) is known to induce oxidative stress along with deranging various metabolisms; one of the late complications of diabetes mellitus is diabetic retinopathy, which is a leading cause of acquired blindness. Poor glycemic control and oxidative stress have been attributed to the development of ...

  4. Retinopathy of Prematurity

    Science.gov (United States)

    Steinweg, Sue Byrd; Griffin, Harold C.; Griffin, Linda W.; Gingras, Happy

    2005-01-01

    The eyes of premature infants are especially vulnerable to injury after birth. A serious complication is called retinopathy of prematurity (ROP), which is abnormal growth of the blood vessels in an infant's eye. Retinopathy of prematurity develops when abnormal blood vessels grow and spread throughout the retina, which is the nerve tissue at the…

  5. Hyperglycemia Induces Toll-Like Receptor-2 and -4 Expression and Activity in Human Microvascular Retinal Endothelial Cells: Implications for Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Uthra Rajamani

    2014-01-01

    Full Text Available Diabetic retinopathy (DR causes visual impairment in working age adults and hyperglycemia-mediated inflammation is central in DR. Toll-like receptors (TLRs play a key role in innate immune responses and inflammation. However, scanty data is available on their role in DR. Hence, in this study, we examined TLR2 and TLR4 mRNA and protein expression and activity in hyperglycemic human retinal endothelial cells (HMVRECs. HMVRECs were treated with hyperglycemia (HG or euglycemia and mRNA and protein levels of TLR-2, TLR-4, MyD88, IRF3, and TRIF as well as NF-κB p65 activation were measured. IL-8, IL-1β, TNF-α and MCP-1, ICAM-1, and VCAM-1 as well as monocyte adhesion to HMVRECs were also assayed. HG (25 mM significantly induced TLR2 and TLR4 mRNA and protein in HMVRECs. It also increased both MyD88 and non-MyD88 pathways, nuclear factor-κB (NF-κB, biomediators, and monocyte adhesion. This inflammation was attenuated by TLR-4 or TLR-2 inhibition, and dual inhibition by a TLR inhibitory peptide as well as TLR2 and 4 siRNA. Additionally, antioxidant treatment reduced TLR-2 and TLR4 expression and downstream inflammatory markers. Collectively, our novel data suggest that hyperglycemia induces TLR-2 and TLR-4 activation and downstream signaling mediating increased inflammation possibly via reactive oxygen species (ROS and could contribute to DR.

  6. [Diabetic retinopathy during pregnancy.

    DEFF Research Database (Denmark)

    Mathiesen, E.R.; Rasmussen, K.L.; Laugesen, C.S.

    2008-01-01

    INTRODUCTION: The aim was to evaluate the prevalence and progression of diabetic retinopathy during pregnancy in women with type 1 or type 2 diabetes. MATERIAL AND METHODS: Dilated fundal photography was performed at approximately 10 and 28 gestational weeks in 58 and 18 women with type 1 and type...... 2 diabetes, respectively. Retinopathy was classified as five stages +/- macular oedema. Progression was defined as deterioration corresponding to at least one stage between the two examinations. Clinical parameters were obtained from the medical records. RESULTS: Diabetic retinopathy was found in 36...... (62%) women with type 1 and three (17%) with type 2 diabetes at the first examination. In 26 (34%) retinopathy progressed; four women developed proliferations, three macular oedema and three reduction of visual acuity >/=0.2 on Snellen's chart in at least one eye. HbA1c in early pregnancy was the only...

  7. 'Teaching corner': Management of Diabetic Retinopathy

    African Journals Online (AJOL)

    based interventions in three areas: primary prevention of retinopathy by optimum ... disease and management of established retinopathy to prevent or mitigate visual loss. ... of retinopathy and timely treatment all diminish the risk of ... types: macular oedema and macular ischaemia which may .... Variation in age of onset.

  8. Aggressive posterior retinopathy of prematurity in large preterm babies in South India.

    Science.gov (United States)

    Shah, Parag K; Narendran, Venkatapathy; Kalpana, Narendran

    2012-09-01

    To describe aggressive posterior retinopathy of prematurity (APROP) in a subset of premature babies, having gestational age (GA) of ≥28 weeks and birth weight (BW) of ≥1000 g. Retrospective observational case series. Case records of 99 babies, who were diagnosed to have APROP between July 2002 and October 2010 were reviewed. Fundus fluorescein angiography (FFA) was carried out in 19 babies. The mean GA was 31.7 weeks (range 28-35 weeks) and mean BW was 1572 g (range 1000-2310 g). All these babies received supplemental unblended oxygen 3 days or longer after birth. Of the 52 babies who had an eye exam in the neonatal intensive care unit prior to discharge, 35 babies had loss of vascularised retina from zone II to zone I and four babies from zone III to zone I, when examined as an outpatient. FFA revealed large geographic areas of vaso-obliteration (more than 30 disc areas) posterior to the shunt vessels within vascularised retina. Features of severe capillary bed loss in the vascularised retina were seen in our cases. Oxygen could be a precipitating factor in causing this retinopathy of prematurity in large babies.

  9. Diabetic Retinopathy: Nature and Extent.

    Science.gov (United States)

    Coughlin, W. Ronald; Patz, Arnall

    1978-01-01

    The authors discuss the incidence and prevalence of diabetic retinopathy in juvenile and maturity onset diabetics, background and proliferative retinopathy, and current modalities of treatment. (Author)

  10. Radiation retinopathy

    International Nuclear Information System (INIS)

    Lumbroso, L.; Desjardins, L.; Dendale, R.; Fourquet, A.

    2002-01-01

    Radiation retinopathy is a retinal micro-angiopathy, observed after irradiation of the eye. It can rarely lead to neo-vascular glaucoma and enucleation due to pain. It is due to a progressive retinal capillary then vascular occlusion. Total irradiation dose, dose fraction, and surface of the irradiated retina seem to be strong predictive factors for radiation retinopathy. Patients who underwent an irradiation near the eye (skull base tumors, nasal and paranasal tumors, or brain tumors) should be followed by periodic ophthalmologic examination to detect and treat when necessary the non perfusion areas. (authors)

  11. AMA0428, A Potent Rock Inhibitor, Attenuates Early and Late Experimental Diabetic Retinopathy.

    Science.gov (United States)

    Hollanders, Karolien; Hove, Inge Van; Sergeys, Jurgen; Bergen, Tine Van; Lefevere, Evy; Kindt, Nele; Castermans, Karolien; Vandewalle, Evelien; van Pelt, Jos; Moons, Lieve; Stalmans, Ingeborg

    2017-02-01

    Diabetic retinopathy (DR) is characterized by an early stage of inflammation and vessel leakage, and an advanced vasoproliferative stage. Also, neurodegeneration might play an important role in disease pathogenesis. The aim of this study was to investigate the effect of the Rho kinase (ROCK) inhibitor, AMA0428, on these processes. The response to ROCK inhibition by AMA0428 (1 µg) was studied in vivo using the murine model for streptozotocin (STZ)-induced diabetes, focusing on early non-proliferative DR features and the oxygen-induced retinopathy (OIR) model to investigate proliferative DR. Intravitreal (IVT) administration of AMA0428 was compared with murine anti-VEGF-R2 antibody (DC101, 6.2 µg) and placebo (H 2 O/PEG; 1C8). Outcome was assessed by analyzing leukostasis using fluorescein isothiocyanate coupled concanavalin A (FITC-ConA) and vessel leakage (bovine serum albumin conjugated with fluorescein isothiocyanate; FITC-BSA)/neovascularization and neurodegeneration by immunohistological approaches (hematoxylin and eosin (H&E), terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL), Brn3a). ELISA and Western blotting were employed to unravel the consequences of ROCK inhibition (1 µM AMA0428) on myosin phosphatase target protein (MYPT)-1 phosphorylation, endothelial nitric oxide synthase (eNOS) phosphorylation, and vascular endothelial growth factor (VEGF) levels in retinas of diabetic mice, on NF-κβ activity and ICAM-1 expression in endothelial cells (ECs). In vivo, AMA0428 significantly reduced vessel leakage and neovascularization, respectively, in the STZ and OIR model, comparable to DC101 therapy. Additionally, the ROCK inhibitor decreased neurodegeneration in both models and inhibited leukostasis by 30% (p diabetic retina and AMA0428 administration resulted in decreased phospho-MYPT-1, enhanced phospho-eNOS, and reduced VEGF levels. In vitro, AMA0428 interfered with NF-κβ activity, thereby inhibiting ICAM-1

  12. Role of agonistic autoantibodies against type-1 angiotensin II receptor in the pathogenesis of retinopathy in preeclampsia.

    Science.gov (United States)

    Liu, Fang; Wang, Yuxian; Wang, Xiaofang; Zheng, Yanqian; Jin, Zhu; Zhi, Jianming

    2016-07-06

    To investigate the mechanism underlying AT1-AA-induced retinopathy in severe preeclampsia by measuring the positive rate and titer of AT1-AA in plasma from women with severe preeclampsia and normal pregnant women to see whether AT1-AA titer was correlated with the grade of retinopathy. A preeclampsia rat model was also established by intravenous injection of AT1-AA extracted from the plasma of patient suffering from severe preeclampsia. The results showed that the plasma titer and positive rate of AT1-AA were significantly higher in women with severe preeclampsia than normal pregnant women. The antibody titer in cases of severe preeclampsia was associated with the grade of retinopathy, and positively correlated with the level of TNF-α and VEGF. The animal experiment results showed that the modeled rats presented symptoms very similar to symptoms of human preeclampsia, including retinopathy. Ocular fundus examination showed retinal microvascular abnormalities, hemorrhaging and leakage in the severe preeclampsia. Morphological changes included edema, thickening of the INL and ONL, and pigment atrophy. TNF-α and VEGF levels were increased in the vitreous humor and retina of the model rats. Our studies results suggest that abnormal expression of AT1-AA could induce damage to retinal capillary endothelial cells and increase vascular permeability, resulting in retinopathy.

  13. Evaluation the index of ophthalmic arteries in diabetic patients with retinopathy compared to diabetic patients without retinopathy using color Doppler ultrasound

    Directory of Open Access Journals (Sweden)

    Mohammad Ghasem Hanafi

    2016-12-01

    Full Text Available Diabetic retinopathy is the most common eye complication in diabetic patients that early detection of this complication is essential. The aim of this study was to evaluate ophthalmic artery index in diabetic retinopathy by Doppler ultrasound. . In this cross-sectional study, 64 patients were studied in 4 groups (healthy, diabetic without retinopathy, background retinopathy and proliferative retinopathy. Resistance index (RI and Pulsatile Index (PI were assessed by color Doppler ultrasound. The obtained data were analyzed by ANOVA and chi-square test and ROC curve. RI in diabetic patients with proliferative retinopathy has the highest mean (0.83 and the lowest mean was observed in healthy subjects (0.54 (P <0.001 as well as in PI, the highest rate was in diabetic patients with proliferative retinopathy (1.41 and the lowest was in healthy subjects (0.92 (P <0.001. The results of our study showed that the sensitivity, specificity, positive and negative predictive values and overall accuracy of RI and PI in diabetic patients with proliferative retinopathy in the best cut-off points (0.645 and 1.0175 respectively were 100%.Ophthalmic artery index RI and PI was significantly increased in patients with diabetic retinopathy and the sensitivity and specificity for detection retinopathy was 100%. Color Doppler ultrasound method is more efficient for screening diabetic patients with retinopathy.

  14. Molecular Mechanisms of Diabetic Retinopathy, General Preventive Strategies, and Novel Therapeutic Targets

    Science.gov (United States)

    Safi, Sher Zaman; Kumar, Selva; Ismail, Ikram Shah Bin

    2014-01-01

    The growing number of people with diabetes worldwide suggests that diabetic retinopathy (DR) and diabetic macular edema (DME) will continue to be sight threatening factors. The pathogenesis of diabetic retinopathy is a widespread cause of visual impairment in the world and a range of hyperglycemia-linked pathways have been implicated in the initiation and progression of this condition. Despite understanding the polyol pathway flux, activation of protein kinase C (KPC) isoforms, increased hexosamine pathway flux, and increased advanced glycation end-product (AGE) formation, pathogenic mechanisms underlying diabetes induced vision loss are not fully understood. The purpose of this paper is to review molecular mechanisms that regulate cell survival and apoptosis of retinal cells and discuss new and exciting therapeutic targets with comparison to the old and inefficient preventive strategies. This review highlights the recent advancements in understanding hyperglycemia-induced biochemical and molecular alterations, systemic metabolic factors, and aberrant activation of signaling cascades that ultimately lead to activation of a number of transcription factors causing functional and structural damage to retinal cells. It also reviews the established interventions and emerging molecular targets to avert diabetic retinopathy and its associated risk factors. PMID:25105142

  15. Hydroxychloroquine retinopathy.

    Science.gov (United States)

    Yusuf, I H; Sharma, S; Luqmani, R; Downes, S M

    2017-06-01

    Hydroxychloroquine (HCQ; Plaquenil) is used increasingly in the management of a variety of autoimmune disorders, with well established roles in dermatology and rheumatology and emerging roles in oncology. Hydroxychloroquine has demonstrated a survival benefit in patients with systemic lupus erythematosus; some clinicians advocate its use in all such patients. However, Hydroxychloroquine and chloroquine (CQ) have been associated with irreversible visual loss due to retinal toxicity. Hydroxychloroquine retinal toxicity is far more common than previously considered; an overall prevalence of 7.5% was identified in patients taking HCQ for greater than 5 years, rising to almost 20% after 20 years of treatment. This review aims to provide an update on HCQ/CQ retinopathy. We summarise emerging treatment indications and evidence of efficacy in systemic disease, risk factors for retinopathy, prevalence among HCQ users, diagnostic tests, and management of HCQ retinopathy. We highlight emerging risk factors such as tamoxifen use, and new guidance on safe dosing, reversing the previous recommendation to use ideal body weight, rather than actual body weight. We summarise uncertainties and the recommendations made by existing HCQ screening programmes. Asian patients with HCQ retinopathy may demonstrate an extramacular or pericentral pattern of disease; visual field testing and retinal imaging should include a wider field for screening in this group. HCQ is generally safe and effective for the treatment of systemic disease but because of the risk of HCQ retinal toxicity, modern screening methods and ideal dosing should be implemented. Guidelines regarding optimal dosing and screening regarding HCQ need to be more widely disseminated.

  16. Ebselen by modulating oxidative stress improves hypoxia-induced macroglial Müller cell and vascular injury in the retina.

    Science.gov (United States)

    Tan, Sih Min; Deliyanti, Devy; Figgett, William A; Talia, Dean M; de Haan, Judy B; Wilkinson-Berka, Jennifer L

    2015-07-01

    Oxidative stress is an important contributor to glial and vascular cell damage in ischemic retinopathies. We hypothesized that ebselen via its ability to reduce reactive oxygen species (ROS) and augment nuclear factor-like 2 (Nrf2) anti-oxidants would attenuate hypoxia-induced damage to macroglial Müller cells and also lessen retinal vasculopathy. Primary cultures of rat Müller cells were exposed to normoxia (21% O2), hypoxia (0.5% O2) and ebselen (2.5 μM) for up to 72 h. Oxygen-induced retinopathy (OIR) was induced in C57BL/6J mice while control mice were housed in room air. Mice received vehicle (saline, 5% dimethyl sulfoxide) or ebselen (10 mg/kg) each day between postnatal days 6-18. In cultured Müller cells, flow cytometry for dihydroethidium revealed that ebselen reduced the hypoxia-induced increase in ROS levels, whilst increasing the expression of Nrf2-regulated anti-oxidant genes, heme oxygenase 1, glutathione peroxidase-1, NAD(P)H dehydrogenase quinone oxidoreductase 1 and glutamate-cysteine ligase. Moreover, in Müller cells, ebselen reduced the hypoxia-induced increase in protein levels of pro-angiogenic and pro-inflammatory factors including vascular endothelial growth factor, interleukin-6, monocyte chemoattractant-protein 1 and intercellular adhesion molecule-1, and the mRNA levels of glial fibrillary acidic protein (GFAP), a marker of Müller cell injury. Ebselen improved OIR by attenuating capillary vaso-obliteration and neovascularization and a concomitant reduction in Müller cell gliosis and GFAP. We conclude that ebselen protects against hypoxia-induced injury of retinal Müller cells and the microvasculature, which is linked to its ability to reduce oxidative stress, vascular damaging factors and inflammation. Agents such as ebselen may be potential treatments for retinopathies that feature oxidative stress-mediated damage to glia and the microvasculature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Low Vision Rehabilitation and Diabetic Retinopathy

    International Nuclear Information System (INIS)

    Khan, Sarfaraz A.

    2007-01-01

    Diabetic retinopathy is emerging as a major cause of blindness. Diabetic retinopathy calls for a multidisciplinary to the patients. Management of the patient requires a team work by the internist, diabetologist, dietician, ophthalmologist and low vision therapist. Diabetic retinopathy very often results in vision loss. It is important for ophthalmologist to recognize the importance of low vision rehabilitation in formulating appropriate treatment strategies. People with low vision loss due to diabetic retinopathy usually experience difficulty in daily life. Most people with diabetic retinopathy (who have remaining useful vision) can be helped with low vision devices. However, often one low vision device may not be suitable for all purposes. A comprehensive low vision evaluation is required to assess the person's current visual status, identify the goals and the visual needs, and then design an individualized vision rehabilitation program to meet these needs. (author)

  18. Prospects for angiotensin receptor blockers in diabetic retinopathy

    DEFF Research Database (Denmark)

    Sjølie, Anne Katrin

    2007-01-01

    Retinopathy is the most common microvascular complication of diabetes mellitus, and is an important cause of blindness worldwide. Clinical trials have demonstrated that tight metabolic control inhibits the progression of retinopathy. Good blood pressure control has been shown to be protective...... in type 2 diabetes, and it may also reduce proliferative retinopathy in type 1 diabetes. However, such control is often difficult to achieve in clinical practice, and may be associated with problems such as hypoglycaemia. New therapies are therefore needed to reduce the risk of retinopathy....... There is growing evidence that the renin-angiotensin system (RAS) plays an important role in the pathogenesis of diabetic retinopathy, and this has led to interest in RAS inhibitors as agents to prevent retinopathy. Several trials have suggested that ACE inhibitor therapy can inhibit progression of retinopathy...

  19. Physical activity and its correlation to diabetic retinopathy.

    Science.gov (United States)

    Praidou, Anna; Harris, Martin; Niakas, Dimitrios; Labiris, Georgios

    2017-02-01

    The lack of physical activity, along with obesity, smoking, hypertension and hyperglycaemia are considered as risk factors for the occurrence of diseases such as diabetes. Primary objective of the study was to investigate potential correlation between physical activity and diabetic retinopathy. Three hundred and twenty patients were included in the study: 240 patients with diabetes type 2 (80 patients with mild to moderate non-proliferative diabetic retinopathy, 80 patients with severe to very severe non-proliferative diabetic retinopathy and 80 ones with proliferative diabetic retinopathy) were compared with 80 non-diabetic patients (control group). Physical activity of patients was assessed by the international physical activity questionnaire (IPAQ, 2002). HbA1c and BMI were also measured in diabetic patients. Group comparisons were attempted for levels of physical activity and sedentary behavior. Total physical activity was decreased in patients with severe to very severe non-proliferative diabetic retinopathy and proliferative diabetic retinopathy as compared to patients with mild to moderate non-proliferative diabetic retinopathy and to the control group (pdiabetic retinopathy and physical activity has been demonstrated (pdiabetic retinopathy, independent of the effects of HbA1c and BMI. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Radiation retinopathy in diabetes mellitus

    International Nuclear Information System (INIS)

    Dhir, S.P.; Joshi, A.V.; Banerjee, A.K.

    1982-01-01

    A case of radiation retinopathy in a diabetic individual who received a total dose of 45 Gy for lymphoblastic lymphoma of the orbit is reported. The relationship between radiation retinopathy and diabetes mellitus is discussed. (Auth.)

  1. Oxidative Stress-Related Mechanisms and Antioxidant Therapy in Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Cheng Li

    2017-01-01

    Full Text Available Diabetic retinopathy (DR is one of the most common microvascular complications of diabetes and is the leading cause of blindness in young adults. Oxidative stress has been implicated as a critical cause of DR. Metabolic abnormalities induced by high-glucose levels are involved in the development of DR and appear to be influenced by oxidative stress. The imbalance between reactive oxygen species (ROS production and the antioxidant defense system activates several oxidative stress-related mechanisms that promote the pathogenesis of DR. The damage caused by oxidative stress persists for a considerable time, even after the blood glucose concentration has returned to a normal level. Animal experiments have proved that the use of antioxidants is a beneficial therapeutic strategy for the treatment of DR, but more data are required from clinical trials. The aims of this review are to highlight the improvements to our understanding of the oxidative stress-related mechanisms underlying the development of DR and provide a summary of the main antioxidant therapy strategies used to treat the disease.

  2. Renal transplantation induces mitochondrial uncoupling, increased kidney oxygen consumption, and decreased kidney oxygen tension

    NARCIS (Netherlands)

    Papazova, Diana A.; Friederich-Persson, Malou; Joles, Jaap A.; Verhaar, Marianne C.

    2015-01-01

    Hypoxia is an acknowledged pathway to renal injury and ischemia-reperfusion (I/R) and is known to reduce renal oxygen tension (PO2). We hypothesized that renal I/R increases oxidative damage and induces mitochondrial uncoupling, resulting in increased oxygen consumption and hence kidney

  3. Effects of normobaric versus hyperbaric oxygen on cell injury induced by oxygen and glucose deprivation in acute brain slices

    Directory of Open Access Journals (Sweden)

    Laurent Chazalviel

    2016-01-01

    Full Text Available Normobaric oxygen (NBO and hyperbaric oxygen (HBO are emerging as a possible co-treatment of acute ischemic stroke. Both have been shown to reduce infarct volume, to improve neurologic outcome, to promote endogenous tissue plasminogen activator-induced thrombolysis and cerebral blood flow, and to improve tissue oxygenation through oxygen diffusion in the ischemic areas, thereby questioning the interest of HBO compared to NBO. In the present study, in order to investigate and compare the oxygen diffusion effects of NBO and HBO on acute ischemic stroke independently of their effects at the vascular level, we used acute brain slices exposed to oxygen and glucose deprivation, an ex vivo model of brain ischemia that allows investigating the acute effects of NBO (partial pressure of oxygen (pO 2 = 1 atmospheres absolute (ATA = 0.1 MPa and HBO (pO 2 = 2.5 ATA = 0.25 MPa through tissue oxygenation on ischemia-induced cell injury as measured by the release of lactate dehydrogenase. We found that HBO, but not NBO, reduced oxygen and glucose deprivation-induced cell injury, indicating that passive tissue oxygenation (i.e. without vascular support of the brain parenchyma requires oxygen partial pressure higher than 1 ATA.

  4. Pericentral retinopathy and racial differences in hydroxychloroquine toxicity.

    Science.gov (United States)

    Melles, Ronald B; Marmor, Michael F

    2015-01-01

    To describe patterns of hydroxychloroquine retinopathy distinct from the classic parafoveal (bull's eye) maculopathy. Retrospective case series. Patients from a large multi-provider group practice and a smaller university referral practice diagnosed with hydroxychloroquine retinopathy. Patients with widespread or "end-stage" retinopathy were excluded. Review of ophthalmic studies (fundus photography, spectral-domain optical coherence tomography, fundus autofluorescence, multifocal electroretinography, visual fields) and classification of retinopathy into 1 of 3 patterns: parafoveal (retinal changes 2°-6° from the fovea), pericentral (retinal changes ≥ 8° from the fovea), or mixed (retinal changes in both parafoveal and pericentral areas). Relative frequency of different patterns of hydroxychloroquine retinopathy and comparison of risk factors. Of 201 total patients (18% Asian) with hydroxychloroquine retinopathy, 153 (76%) had typical parafoveal changes, 24 (12%) also had a zone of pericentral damage, and 24 (12%) had pericentral retinopathy without any parafoveal damage. Pericentral retinopathy alone was seen in 50% of Asian patients but only in 2% of white patients. Patients with the pericentral pattern were taking hydroxychloroquine for a somewhat longer duration (19.5 vs. 15.0 years, P Hydroxychloroquine retinopathy does not always develop in a parafoveal (bull's eye) pattern, and a pericentral pattern of damage is especially prevalent among Asian patients. Screening practices may need to be adjusted to recognize pericentral and parafoveal hydroxychloroquine retinopathy. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  5. Diabetic retinopathy screening: global and local perspective.

    Science.gov (United States)

    Gangwani, R A; Lian, J X; McGhee, S M; Wong, D; Li, K Kw

    2016-10-01

    Diabetes mellitus has become a global epidemic. It causes significant macrovascular complications such as coronary artery disease, peripheral artery disease, and stroke; as well as microvascular complications such as retinopathy, nephropathy, and neuropathy. Diabetic retinopathy is known to be the leading cause of blindness in the working-age population and may be asymptomatic until vision loss occurs. Screening for diabetic retinopathy has been shown to reduce blindness by timely detection and effective laser treatment. Diabetic retinopathy screening is being done worldwide either as a national screening programme or hospital-based project or as a community-based screening programme. In this article, we review different methods of screening including grading used to detect the severity of sight-threatening retinopathy and the newer screening methods. This review also includes the method of systematic screening being carried out in Hong Kong, a system that has helped to identify diabetic retinopathy among all attendees in public primary care clinics using a Hong Kong-wide public patients' database.

  6. Endocrinological disturbances in diabetic retinopathy

    International Nuclear Information System (INIS)

    Hafiez, A.A.; Shalaby, E.; Atia, H.; Abdel-Hafez, M.A.; Hammad, A.B.

    1985-01-01

    Microvascular complications of diabetes mellitus were extensively studied from various points of view. The aim was to elucidate the possible interaction of insulin, glucagon, prolactin, growth hormone, T 3 , and T 4 in the pathogenesis of diabetic retinopathy. Forty patients with diabetic retinopathy (group II) and twenty age-matched controls (group I) were investigated. Plasma levels of both insulin and glucagon were significantly elevated in group II versus group I, whereas other hormones were insignificantly changed. This shows the role that might be played by T 3 , T 4 , growth hormone, and prolactin in the established cases of diabetic retinopathy. (author)

  7. Effective panphotocoagulation in a case of radiation retinopathy

    International Nuclear Information System (INIS)

    Mori, Tatsuhiko; Tochikubo, Tetsuo; Shinohara, Atsuko; Komoto, Michiji; Tabata, Toshifumi.

    1992-01-01

    This paper reports a case of radiation retinopathy caused by 60 Co and Ra radiation therapy following surgery for carcinoma of the maxillary sinus in a 42-year-old male. The retinopathy was found at onset of vitreous hemorrhage; the proliferative retinopathy was disclosed by fluorescein angiography (FAG). The retinopathy was treated a total of five times with both argon and krypton laser photocoagulation (PHC). As a result, both the subjective and objective symptoms improved. When radiation retinopathy is suspected, FAG must be conducted as soon as possible, to decide whether PHC is needed or not. (author)

  8. Preclinical screening for retinopathy of prematurity risk using IGF1 levels at 3 weeks post-partum.

    Science.gov (United States)

    Pérez-Muñuzuri, Alejandro; Couce-Pico, Maria Luz; Baña-Souto, Ana; López-Suárez, Olalla; Iglesias-Deus, Alicia; Blanco-Teijeiro, José; Fernández-Lorenzo, José Ramón; Fraga-Bermúdez, José María

    2014-01-01

    Following current recommendations for preventing retinopathy of prematurity (ROP) involves screening a large number of patients. We performed a prospective study to establish a useful screening system for ROP prediction and we have determined that measuring serum levels of IGF1 at week three and the presence of sepsis have a high predictive value for the subsequent development of ROP. A total of 145 premature newborn, with birthweight <1500 g and/or <32 weeks gestational age, were enrolled. 26.9% of them showed some form of retinopathy. A significant association was found between the development of retinopathy and each of the following variables: early gestational age, low birthweight, requiring mechanical ventilation, oxygen treatment, intracranial haemorrhage, sepsis during the first three weeks, bronchopulmonary dysplasia, the need for erythrocyte transfusion, erythropoietin treatment, and low levels of serum IGF1 in the third week. A multiple logistic regression analysis was used to obtain curves for the probability of developing ROP, based on the main factors linked with ROP, namely serum levels of IGF1 and presence of sepsis. Such preclinical screening has the ability to identify patients with high-risk of developing retinopathy and should lead to better prediction for ROP, while at the same time optimising the use of clinical resources, both human and material.

  9. Effect of pregnancy on diabetic nephropathy and retinopathy

    International Nuclear Information System (INIS)

    Irfan, S.; Arain, M.; Shahid, A.; Shaukat, A.

    2004-01-01

    Objective: To determine whether pregnancy worsens renal function in women with diabetic nephropathy and the effect of pregnancy on diabetic retinopathy. Subject and Methods: Thirty-five patients (aged 20-36 years) identified with diabetic nephropathy and moderate to severe renal dysfunction (creatinine Cr) - > 1.4 mg/dl) at pregnancy onset by retrospective chart review. Alterations in glomerular filtration rate (GFR) were estimated. An equal number of non-pregnant premenopausal type I diabetic women with similar degrees of renal dysfunction served as controls for non-pregnant rate of decline of renal function and potential contributing factors. Student's t-test and repeated measures analysis of variance were analyzed. Results: Mean serum Cr rose from 1.8 mg/dl pre pregnancy to 2.5 mg/dl in the third trimester. Renal function was stable in 27%, showed transient worsening in pregnancy in 27%, and demonstrated a permanent decline in 45%. Proteinuria increased in pregnancy in 79%. Exacerbation of hypertension or pre-eclampsia occurred in 73% and 71% of these showed acceleration of disease during the pregnancy. All the patients had diabetic retinopathy, though proliferative retinopathy was diagnosed and treated in only 54.5.% pre pregnancy. The retinopathy progressed, requiring laser therapy, in 45.4%. Macular edema was noted in 6 of the patients. Other diabetic complications included peripheral and autonomic neuropathy in 8 patients. Conclusion: Pregnancy induced progression is seen in the decline of renal functions. Patients with diabetic nephropathy were found to have a > 40% chance of accelerated progression of their disease as a result of pregnancy. Forty-five percent of the patients had permanent decline in GFR in association with pregnancy. (author)

  10. Global prevalence and major risk factors of diabetic retinopathy

    DEFF Research Database (Denmark)

    Yau, Joanne W Y; Rogers, Sophie L; Kawasaki, Ryo

    2012-01-01

    To examine the global prevalence and major risk factors for diabetic retinopathy (DR) and vision-threatening diabetic retinopathy (VTDR) among people with diabetes.......To examine the global prevalence and major risk factors for diabetic retinopathy (DR) and vision-threatening diabetic retinopathy (VTDR) among people with diabetes....

  11. Purtscher-like retinopathy in systemic lupus erythematosus.

    Science.gov (United States)

    Wu, Chan; Dai, Rongping; Dong, Fangtian; Wang, Qian

    2014-12-01

    To investigate clinical characteristics of Purtscher-like retinopathy and its clinical implications among patients with systemic lupus erythematosus (SLE). Observational case series. setting: Tertiary medical center. patient population: Patients with SLE who were diagnosed with Purtscher-like retinopathy between 2002 and 2013. observation procedures: Assessment and follow-up in the ophthalmology department. main outcome measure: Visual acuity and funduscopic examination at presentation and at 6 month follow-up, with analysis of the association between Purtscher-like retinopathy and other systemic involvement of SLE and overall disease activity. Among 5688 patients with SLE evaluated, 8 cases of Purtscher-like retinopathy were diagnosed. Typical fundus abnormalities included Purtscher flecken, cotton-wool spots, retinal hemorrhages, macular edema, optic disk swelling, and a pseudo-cherry red spot. Fluorescein angiography abnormalities included areas of capillary nonperfusion corresponding to the retinal whitening, late leakage, peripapillary staining, precapillary occlusion, and slower filling of vessels. The prevalence of central nervous system lupus was significantly higher among those with Purtscher-like retinopathy (6/8) than among 240 patients randomly sampled from those without Purtscher-like retinopathy. A very high SLE Disease Activity Index (≥20) was present in all 8 patients with Purtscher-like retinopathy. All patients received corticosteroids combined with immunosuppressants. For the majority of patients, optic atrophy developed during follow-up with persistent low visual acuity. As a rare and severe ophthalmic complication of SLE, Purtscher-like retinopathy was associated with central nervous system lupus and highly active disease. Visual acuity recovery was usually poor despite prompt treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Endoplasmic reticulum stress and diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Toshiyuki Oshitari

    2008-02-01

    Full Text Available Toshiyuki Oshitari1,2, Natsuyo Hata1, Shuichi Yamamoto11Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba City, Chiba, Japan; 2Department of Ophthalmology, Kimitsu Central Hospital, Kisarazu City, Chiba, JapanAbstract: Endoplasmic reticulum (ER stress is involved in the pathogenesis of several diseases including Alzheimer disease and Parkinson disease. Many recent studies have shown that ER stress is related to the pathogenesis of diabetes mellitus, and with the death of pancreatic β-cells, insulin resistance, and the death of the vascular cells in the retina. Diabetic retinopathy is a major complication of diabetes and results in death of both neural and vascular cells. Because the death of the neurons directly affects visual function, the precise mechanism causing the death of neurons in early diabetic retinopathy must be determined. The ideal therapy for preventing the onset and the progression of diabetic retinopathy would be to treat the factors involved with both the vascular and neuronal abnormalities in diabetic retinopathy. In this review, we present evidence that ER stress is involved in the death of both retinal neurons and vascular cells in diabetic eyes, and thus reducing or blocking ER stress may be a potential therapy for preventing the onset and the progression of diabetic retinopathy.Keywords: endoplasmic reticulum stress, diabetic retinopathy, vascular cell death, neuronal cell death

  13. Diabetic Retinopathy Grading by Digital Curvelet Transform

    Directory of Open Access Journals (Sweden)

    Shirin Hajeb Mohammad Alipour

    2012-01-01

    Full Text Available One of the major complications of diabetes is diabetic retinopathy. As manual analysis and diagnosis of large amount of images are time consuming, automatic detection and grading of diabetic retinopathy are desired. In this paper, we use fundus fluorescein angiography and color fundus images simultaneously, extract 6 features employing curvelet transform, and feed them to support vector machine in order to determine diabetic retinopathy severity stages. These features are area of blood vessels, area, regularity of foveal avascular zone, and the number of micro-aneurisms therein, total number of micro-aneurisms, and area of exudates. In order to extract exudates and vessels, we respectively modify curvelet coefficients of color fundus images and angiograms. The end points of extracted vessels in predefined region of interest based on optic disk are connected together to segment foveal avascular zone region. To extract micro-aneurisms from angiogram, first extracted vessels are subtracted from original image, and after removing detected background by morphological operators and enhancing bright small pixels, micro-aneurisms are detected. 70 patients were involved in this study to classify diabetic retinopathy into 3 groups, that is, (1 no diabetic retinopathy, (2 mild/moderate nonproliferative diabetic retinopathy, (3 severe nonproliferative/proliferative diabetic retinopathy, and our simulations show that the proposed system has sensitivity and specificity of 100% for grading.

  14. Lipoprotein(a Serum Levels in Diabetic Patients with Retinopathy

    Directory of Open Access Journals (Sweden)

    Giulia Malaguarnera

    2013-01-01

    Full Text Available Background. Atherogenic lipoproteins, such as total cholesterol, LDL cholesterol, oxidized low density lipoprotein, and triglycerides, are associated with progression of retinopathy. Aim. To evaluate the relationship between lipoprotein(a and retinopathy in patients with type 2 diabetes mellitus. Materials and Methods. We enrolled 145 diabetic consecutive patients (82 females, 63 males; mean age 66.8±12 years, mean duration of diabetes 9.4±6.8 years. Presence and severity of retinopathy were evaluated. Serum lipid profile, including Lp(a level, was assessed. Results. High Lp(a levels have been observed in 54 (78.3% subjects and normal levels in 13 (18.85% subjects as regards diabetic patients with retinopathy. Lp(a levels were high in 15 subjects (21.75% and normal in 63 subjects (91.35% as regards patients without retinopathy. Conclusions. Lp(a levels are increased in a significant percentage of patients with retinopathy compared to diabetic patients without retinopathy. The impact of Lp(a levels on diabetic retinopathy needs to be further investigated.

  15. Diabetic retinopathy in acromegaly

    Directory of Open Access Journals (Sweden)

    Said Azzoug

    2014-01-01

    Full Text Available Introduction: Although growth hormone (GH has been implicated in the pathogenesis of diabetic retinopathy (DR, DR is deemed to be rare in patients with GH excess. Our aim was to study its prevalence in subjects with acromegaly suffering from diabetes mellitus (DM, to analyze its characteristics, and to look for predictive factors such as age at diagnosis, GH concentration and duration, DM duration, DM control, and family background. Materials and Methods: Forty patients with acromegaly and DM (21 males, 19 females, median age = 50 years, underwent a systematic ophthalmological examination with dilated funduscopy to seek diabetic retinopathy. Results: Among this population, 05 (12.5% had DR. It was at an early stage or background retinopathy in 3 cases and at a more advanced stage or proliferative retinopathy in 2 cases. We did not find any correlation with age at diagnosis, GH levels and duration, DM duration and family history of DM, but poor glycemic control seems to play a role although statistical analysis showed borderline significance. Conclusion: From this study, we conclude that prevalence of DR in patients with acromegaly is 12.5%, and it is slight or moderate. Among studied factors, only poor glycemic control seems to be implicated in its development.

  16. Diabetic retinopathy in two patients with congenital IGF-I deficiency (Laron syndrome).

    Science.gov (United States)

    Laron, Zvi; Weinberger, Dov

    2004-07-01

    Animal and clinical studies have shown that excessive amounts of growth hormone or insulin-like growth factor-I (IGF-I) promote the development of diabetes and diabetic retinopathy. Forthwith, we present two patients with congenital IGF-I deficiency who developed type II diabetes and subsequently retinopathy. Eighteen adult patients with classical Laron syndrome (8 males, 10 females, aged 20-62 years) were followed by us since childhood or underwent fundus photography with a Nikon NF 505 instrument. Three had been treated in childhood with IGF-I, the rest were never treated, including the two patients reported. Two never-treated patients were diagnosed with type II diabetes (DM) at ages 39 and 41 respectively. There was no diabetes in the families. Oral treatment was followed by insulin injections. Metabolic control was not optimal and one patient developed proliferative diabetic retinopathy, necessitating laser surgery. He also has nephropathy and severe neuropathy. The other patient has background diabetic retinopathy and has developed, progressively, exudates, microaneurisms, hemorrhages and clinically significant macular edema. He also has subacute ischemic heart disease. Our findings show that congenital IGF-I deficiency, similar to excess, causes vascular complications of DM, denoting also that vascular endothelial growth factor can induce neovascularization in the presence of congenital IGF-I deficiency.

  17. Diabetic retinopathy in a remote Indigenous primary healthcare population: a Central Australian diabetic retinopathy screening study in the Telehealth Eye and Associated Medical Services Network project.

    Science.gov (United States)

    Brazionis, L; Jenkins, A; Keech, A; Ryan, C; Brown, A; Boffa, J; Bursell, S

    2018-05-01

    To determine diabetic retinopathy prevalence and severity among remote Indigenous Australians. A cross-sectional diabetic retinopathy screening study of Indigenous adults with Type 2 diabetes was conducted by locally trained non-ophthalmic retinal imagers in a remote Aboriginal community-controlled primary healthcare clinic in Central Australia and certified non-ophthalmic graders in a retinal grading centre in Melbourne, Australia. The main outcome measure was prevalence of any diabetic retinopathy and sight-threatening diabetic retinopathy. Among 301 participants (33% male), gradable image rates were 78.7% (n = 237) for diabetic retinopathy and 83.1% (n = 250) for diabetic macular oedema, and 77.7% (n = 234) were gradable for both diabetic retinopathy and diabetic macular oedema. For the gradable subset, the median (range) age was 48 (19-86) years and known diabetes duration 9.0 (0-24) years. The prevalence of diabetic retinopathy was 47% (n = 110) and for diabetic macular oedema it was 14.4% (n = 36). In the fully gradable imaging studies, sight-threatening diabetic retinopathy prevalence was 16.2% (n = 38): 14.1% (n = 33) for clinically significant macular oedema, 1.3% (n = 3) for proliferative diabetic retinopathy and 0.9% (n = 2) for both. Sight-threatening diabetic retinopathy had been treated in 78% of detected cases. A novel telemedicine diabetic retinopathy screening service detected a higher prevalence of 'any' diabetic retinopathy and sight-threatening diabetic retinopathy in a remote primary care setting than reported in earlier surveys among Indigenous and non-Indigenous populations. Whether the observed high prevalence of diabetic retinopathy was attributable to greater detection, increasing diabetic retinopathy prevalence, local factors, or a combination of these requires further investigation and, potentially, specific primary care guidelines for diabetic retinopathy management in remote Australia. Clinical Trials registration number: Australia and

  18. Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion

    International Nuclear Information System (INIS)

    Kyriacou, P A; Shafqat, K; Pal, S K

    2007-01-01

    Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO 2 ) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO 2 ) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO 2 sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures. Both pulse

  19. Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion

    Science.gov (United States)

    Kyriacou, P. A.; Shafqat, K.; Pal, S. K.

    2007-10-01

    Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO2) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO2) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO2 sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures. Both pulse

  20. Choroidal Thinning Associated With Hydroxychloroquine Retinopathy.

    Science.gov (United States)

    Ahn, Seong Joon; Ryu, So Jung; Joung, Joo Young; Lee, Byung Ro

    2017-11-01

    To investigate choroidal thickness in patients using hydroxychloroquine (HCQ) and compare choroidal thickness between eyes with and without HCQ retinopathy. Retrospective case series. Setting: Institutional. We included 124 patients with systemic lupus erythematosus or rheumatoid arthritis who were treated with HCQ. The patients were divided into an HCQ retinopathy group and a control group, according to the presence or absence of HCQ retinopathy. Total choroidal thickness and choriocapillaris-equivalent thickness were measured manually by 2 independent investigators using swept-source optical coherence tomography (SS-OCT; DRI-OCT, Topcon Inc, Tokyo, Japan). These measurements were made at the fovea and at nasal and temporal locations 0.5, 1.5, and 3 mm from the fovea. Medium-to-large vessel layer thickness was calculated accordingly. The thicknesses were compared between the HCQ retinopathy and control groups. We performed correlation analyses between choroidal thicknesses and details regarding HCQ use. Total choroidal thickness and choriocapillaris-equivalent thickness. Choroidal thicknesses were significantly decreased (P < .05) in the HCQ retinopathy group compared to the control group, except at the temporal choroid 1.5 mm from the fovea. Choriocapillaris-equivalent thicknesses were significantly different in all choroidal locations between the groups. In contrast, the medium-to-large vessel layer thickness was only significantly different at a few locations. The cumulative dose/body weight was significantly correlated with subfoveal choroidal and choriocapillaris-equivalent thicknesses (both P = .001). The association between presence of HCQ retinopathy and choroidal thicknesses was also statistically significant after adjusting for age, diagnosis for HCQ use, refractive errors, and duration of HCQ use (P = .001 and P = .003 for subfoveal choroidal and choriocapillaris-equivalent thickness, respectively). These results all suggest that HCQ retinopathy is

  1. Awareness of diabetic retinopathy among patients with diabetes ...

    African Journals Online (AJOL)

    Background: Diabetic retinopathy is a major cause of blindness worldwide. The associated loss of productivity and quality of life of the patients with diabetic retinopathy will lead to additional socioeconomic burden. This study aims to determine the level of awareness of diabetic retinopathy among diabetic patients. Materials ...

  2. Preclinical screening for retinopathy of prematurity risk using IGF1 levels at 3 weeks post-partum.

    Directory of Open Access Journals (Sweden)

    Alejandro Pérez-Muñuzuri

    Full Text Available Following current recommendations for preventing retinopathy of prematurity (ROP involves screening a large number of patients. We performed a prospective study to establish a useful screening system for ROP prediction and we have determined that measuring serum levels of IGF1 at week three and the presence of sepsis have a high predictive value for the subsequent development of ROP. A total of 145 premature newborn, with birthweight <1500 g and/or <32 weeks gestational age, were enrolled. 26.9% of them showed some form of retinopathy. A significant association was found between the development of retinopathy and each of the following variables: early gestational age, low birthweight, requiring mechanical ventilation, oxygen treatment, intracranial haemorrhage, sepsis during the first three weeks, bronchopulmonary dysplasia, the need for erythrocyte transfusion, erythropoietin treatment, and low levels of serum IGF1 in the third week. A multiple logistic regression analysis was used to obtain curves for the probability of developing ROP, based on the main factors linked with ROP, namely serum levels of IGF1 and presence of sepsis. Such preclinical screening has the ability to identify patients with high-risk of developing retinopathy and should lead to better prediction for ROP, while at the same time optimising the use of clinical resources, both human and material.

  3. ROCK-1 mediates diabetes-induced retinal pigment epithelial and endothelial cell blebbing: Contribution to diabetic retinopathy.

    Science.gov (United States)

    Rothschild, Pierre-Raphaël; Salah, Sawsen; Berdugo, Marianne; Gélizé, Emmanuelle; Delaunay, Kimberley; Naud, Marie-Christine; Klein, Christophe; Moulin, Alexandre; Savoldelli, Michèle; Bergin, Ciara; Jeanny, Jean-Claude; Jonet, Laurent; Arsenijevic, Yvan; Behar-Cohen, Francine; Crisanti, Patricia

    2017-08-18

    In diabetic retinopathy, the exact mechanisms leading to retinal capillary closure and to retinal barriers breakdown remain imperfectly understood. Rho-associated kinase (ROCK), an effector of the small GTPase Rho, involved in cytoskeleton dynamic regulation and cell polarity is activated by hyperglycemia. In one year-old Goto Kakizaki (GK) type 2 diabetic rats retina, ROCK-1 activation was assessed by its cellular distribution and by phosphorylation of its substrates, MYPT1 and MLC. In both GK rat and in human type 2 diabetic retinas, ROCK-1 is activated and associated with non-apoptotic membrane blebbing in retinal vessels and in retinal pigment epithelium (RPE) that respectively form the inner and the outer barriers. Activation of ROCK-1 induces focal vascular constrictions, endoluminal blebbing and subsequent retinal hypoxia. In RPE cells, actin cytoskeleton remodeling and membrane blebs in RPE cells contributes to outer barrier breakdown. Intraocular injection of fasudil, significantly reduces both retinal hypoxia and RPE barrier breakdown. Diabetes-induced cell blebbing may contribute to ischemic maculopathy and represent an intervention target.

  4. Neuroprotective effect of He-Ying-Qing-Re formula on retinal ganglion cell in diabetic retinopathy.

    Science.gov (United States)

    Zhang, Cheng; Xu, Yu; Tan, Hor-Yue; Li, Sha; Wang, Ning; Zhang, Yinjian; Feng, Yibin

    2018-03-25

    He-Ying-Qing-Re Formula (HF) was empirically modified from Si-Miao-Yong-An Decoction (SD), which was recorded in the literature of Divine Doctor's Secret Transmission, and has been utilized for centuries to treat vasculopathy through clearing heat and accelerating bloodstream. HF has been used as an effective holistic treatment of diabetic retinopathy (DR) for decades and experimentally reported to ameliorate retinal condition in diabetic mice. Our study aims to investigate the effect of HF in preventing sustained hyperglycemia and hyperlipidemia-associated retinal ganglion cell (RGC) cell death and its possible mechanism. Chromatographic fingerprint of HF was obtained upon the UPLC-based analytic system; Diabetic retinopathy was established in streptozotocin (STZ) injection-induced hyperglycemic mice; Alterations of retinal structure was assayed by H&E staining. Expression of PSD-95 and CHOP in retinae was assessed by immunofluorescence; RGC cell line (mRGC) was used for in vitro study. Cell death was analyzed by flow cytometry; Intracellular reactive oxygen species (ROS) was measured by 2',7'-dichlorofluorescin diacetate (DCFDA); Apoptosis-related proteins and signaling were monitored with immunoblotting and colorimetric assay. Chlorogenic acid, ferulic acid, and rutin were identified in HF. HF attenuates the loss of RGCs, thinning of inner retinal layers in diabetic mice. Furthermore, expressions of Brn3a and PSD-95 were restored while CHOP level was downregulated upon HF treatment. In vitro study, HF alleviates H 2 O 2 -induced apoptosis of mRGCs and loss of postsynaptic protein via scavenging ROS and suppressing ATF4/CHOP-mediated endoplasmic reticulum stress and mitochondria-related pro-apoptotic factors, probably as cleaved-caspase-3, and phospho-p38 mitogen-activated protein kinase (MARK). Meanwhile, both pro-survival protein levels like Bcl-2/Bcl-xL and postsynaptic protein of PSD-95 were upregulated upon HF treatment. HF administration was a valid

  5. Role of macular xanthophylls in prevention of common neovascular retinopathies: retinopathy of prematurity and diabetic retinopathy.

    Science.gov (United States)

    Gong, Xiaoming; Rubin, Lewis P

    2015-04-15

    Retinopathy of prematurity (ROP) and diabetic retinopathy (DR) are important causes of blindness among children and working-age adults, respectively. The development of both diseases involves retinal microvascular degeneration, vessel loss and consequent hypoxic and inflammatory pathologic retinal neovascularization. Mechanistic studies have shown that oxidative stress and subsequent derangement of cell signaling are important factors in disease progression. In eye and vision research, role of the dietary xanthophyll carotenoids, lutein and zeaxanthin, has been more extensively studied in adult onset macular degeneration than these other retinopathies. These carotenoids also may decrease severity of ROP in preterm infants and of DR in working-age adults. A randomized controlled clinical trial of carotenoid supplementation in preterm infants indicated that lutein has functional effects in the neonatal eye and is anti-inflammatory. Three multicenter clinical trials all showed a trend of decreased ROP severity in the lutein supplemented group. Prospective studies on patients with non-proliferative DR indicate serum levels of lutein and zeaxanthin are significantly lower in these patients compared to normal subjects. The present review describes recent advances in lutein and zeaxanthin modulation of oxidative stress and inflammation related to ROP and DR and discusses potential roles of lutein/zeaxanthin in preventing or lessening the risks of disease initiation or progression. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Fundus fluorescence Angiography in diagnosing diabetic retinopathy.

    Science.gov (United States)

    Wang, Shuhui; Zuo, Yuqin; Wang, Ning; Tong, Bin

    2017-01-01

    To investigate the manifestation characteristics of fundus fluorescence angiography (FFA) and its values in diagnosing diabetic retinopathy through comparing direct ophthalmoscopy. Two hundred fifty patients (500 eyes) who were suspected as diabetic retinopathy and admitted to the hospital between February 2015 and December 2016 were selected. They underwent direct ophthalmoscopy and FFA. The manifestation characteristics of FFA in the diagnosis of diabetic retinopathy were summarized. The two examination methods were compared. In the diagnosis with direct ophthalmoscopy, 375 eyes out of 500 eyes were diagnosed as diabetic retinopathy (75%); there were 74 eyes at stage I, 88 eyes at stage II, 92 eyes at stage III, 83 eyes of stage IV, 28 eyes of stage V and 10 eyes of stage VI. In the diagnosis with FFA, 465 eyes out of 500 eyes were diagnosed as diabetic retinopathy (93%); there were 94 eyes at stage I, 110 eyes at stage II, 112 at stage III, 92 eyes at stage IV, 41 eyes at stage V and 16 eyes at stage VI. The detection rate of diabetic retinopathy using FFA was significantly higher than that using direct ophthalmoscopy (Pretinopathy (67.96%), 75 eyes had pre-proliferative lesions (16.13%), 149 eyes had proliferative lesions (32.04%), 135 eyes had diabetic maculopathy (29.03%) and 31 eyes had diabetic optic disc lesions (6.67%). The detection rate of diabetic retinopathy using FFA is higher than that using direct ophthalmoscopy. FFA could accurately determine clinical stage. Therefore, it is an important approach in treatment efficacy evaluation and treatment guidance, suggesting a significant application value.

  7. Histone HIST1H1C/H1.2 regulates autophagy in the development of diabetic retinopathy.

    Science.gov (United States)

    Wang, Wenjun; Wang, Qing; Wan, Danyang; Sun, Yue; Wang, Lin; Chen, Hong; Liu, Chengyu; Petersen, Robert B; Li, Jianshuang; Xue, Weili; Zheng, Ling; Huang, Kun

    2017-05-04

    Autophagy plays critical and complex roles in many human diseases, including diabetes and its complications. However, the role of autophagy in the development of diabetic retinopathy remains uncertain. Core histone modifications have been reported involved in the development of diabetic retinopathy, but little is known about the histone variants. Here, we observed increased autophagy and histone HIST1H1C/H1.2, an important variant of the linker histone H1, in the retinas of type 1 diabetic rodents. Overexpression of histone HIST1H1C upregulates SIRT1 and HDAC1 to maintain the deacetylation status of H4K16, leads to upregulation of ATG proteins, then promotes autophagy in cultured retinal cell line. Histone HIST1H1C overexpression also promotes inflammation and cell toxicity in vitro. Knockdown of histone HIST1H1C reduces both the basal and stresses (including high glucose)-induced autophagy, and inhibits high glucose induced inflammation and cell toxicity. Importantly, AAV-mediated histone HIST1H1C overexpression in the retinas leads to increased autophagy, inflammation, glial activation and neuron loss, similar to the pathological changes identified in the early stage of diabetic retinopathy. Furthermore, knockdown of histone Hist1h1c by siRNA in the retinas of diabetic mice significantly attenuated the diabetes-induced autophagy, inflammation, glial activation and neuron loss. These results indicate that histone HIST1H1C may offer a novel therapeutic target for preventing diabetic retinopathy.

  8. Automated early detection of diabetic retinopathy

    NARCIS (Netherlands)

    Abràmoff, M.D.; Reinhardt, J.M.; Russell, S.R.; Folk, J.C.; Mahajan, V.B.; Niemeijer, M.; Quellec, G.

    2010-01-01

    Purpose To compare the performance of automated diabetic retinopathy (DR) detection, using the algorithm that won the 2009 Retinopathy Online Challenge Competition in 2009, the Challenge2009, against that of the one currently used in EyeCheck, a large computer-aided early DR detection project.

  9. Consumption of polyphenol-rich Morus alba leaves extract attenuates early diabetic retinopathy: the underlying mechanism.

    Science.gov (United States)

    Mahmoud, Ayman M; Abd El-Twab, Sanaa M; Abdel-Reheim, Eman S

    2017-06-01

    Beneficial effects of white mulberry against diabetes mellitus have been reported. However, the molecular mechanisms of how white mulberry can attenuate diabetic retinopathy remain poorly understood. Here, the mechanism underlying the protective effect of Morus alba leaves ethanolic extract on oxidative stress, inflammation, apoptosis, and angiogenesis in diabetic retinopathy was investigated. Diabetes was induced by injection of streptozotocin. One week after, M. alba (100 mg/kg) was administrated to the rats daily for 16 weeks. Morus alba extract showed high content of polyphenolics and free radical scavenging activity. Oral M. alba administration significantly attenuated hyperglycemia and weight loss, and decreased sorbitol, fructose, protein kinase C, pro-inflammatory cytokines, and oxidative stress markers in retinas of the diabetic rats. Moreover, M. alba produced marked down-regulation of caspase-3 and Bax, with concomitant up-regulation of Bcl-2 in the diabetic retinas. M. alba also reduced the expression of VEGF in the retina. These results indicate that M. alba has protective effect on diabetic retinopathy with possible mechanisms of inhibiting hyperglycemia-induced oxidative stress, apoptosis, inflammation, polyol pathway activation, and VEGF expression in the retina.

  10. Risk factors for diabetic retinopathy in Kuwaiti type 2 diabetic patients

    International Nuclear Information System (INIS)

    Al-Adsani, Afaf M.S.

    2007-01-01

    To determine the risk factors associated with diabetic retinopathy in Kuwaiti subjects with type 2 diabetes. Kuwaiti subjects with type 2 diabetes (n=165) attending the Diabetic Clinic at Al-sabah Hospital, Kuwait between October 2000 and March 2005 were screened for diabetic retinopathy. Any diabetic retinopathy was found in 40% while 20.6% had sight threatening retinopathy. Mild NPDR was present in 21.2%, moderate to severe non-proliferative diabetic retinopathy (NPDR) in 7.9%, and proliferative diabetic retinopathy in 3.0%. Maculopathy was present in 10.3% and 7.9 % pf patients were photocoagulated. Compared to those without retinopathy, diabetic patients with any retinopathy were significantly older (51.7+-10.3 versus 47.2+-9.5 years; p<0.005), had longer duration of diabetes (13.1+-6.3 versus 4.7 +-5.4 years; p<0.0001), higher systolic blood pressure (142.9+-23.0 versus 130.3+-20.2; p<0.0001) and poor glycemic control (Hemoglobin A1c=10.1+-2.4 versus 8.9+-2.3; p<0.005). The prevalence of hypertension and nephropathy was significantly higher in patients with any retinopathy than those without retinopathy (70.8% versus 49.5%; p<0.01 and 64.4% versus 30.8%; p<0.0001) respectively. Longer duration of diabetes and presence of nephropathy was the most significant independent factors associated with any retinopathy and sight-threatening retinopathy. Treatment with sulphonylurea or insulin, and poor glycemic control were other significant independent factors associated with any retinopathy. Longer duration of diabetes, presence of nephropathy, glycemic control and mode of treatment were the most significant independent factors of diabetic retinopathy. However, population-based study is warranted to identify the risk factors, as well as the prevalence of diabetic retinopathy. (author)

  11. Role of Inflammation in Diabetic Retinopathy

    Science.gov (United States)

    Rübsam, Anne; Parikh, Sonia; Fort, Patrice E.

    2018-01-01

    Diabetic retinopathy is a common complication of diabetes and remains the leading cause of blindness among the working-age population. For decades, diabetic retinopathy was considered only a microvascular complication, but the retinal microvasculature is intimately associated with and governed by neurons and glia, which are affected even prior to clinically detectable vascular lesions. While progress has been made to improve the vascular alterations, there is still no treatment to counteract the early neuro-glial perturbations in diabetic retinopathy. Diabetes is a complex metabolic disorder, characterized by chronic hyperglycemia along with dyslipidemia, hypoinsulinemia and hypertension. Increasing evidence points to inflammation as one key player in diabetes-associated retinal perturbations, however, the exact underlying molecular mechanisms are not yet fully understood. Interlinked molecular pathways, such as oxidative stress, formation of advanced glycation end-products and increased expression of vascular endothelial growth factor have received a lot of attention as they all contribute to the inflammatory response. In the current review, we focus on the involvement of inflammation in the pathophysiology of diabetic retinopathy with special emphasis on the functional relationships between glial cells and neurons. Finally, we summarize recent advances using novel targets to inhibit inflammation in diabetic retinopathy. PMID:29565290

  12. Role of Inflammation in Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Anne Rübsam

    2018-03-01

    Full Text Available Diabetic retinopathy is a common complication of diabetes and remains the leading cause of blindness among the working-age population. For decades, diabetic retinopathy was considered only a microvascular complication, but the retinal microvasculature is intimately associated with and governed by neurons and glia, which are affected even prior to clinically detectable vascular lesions. While progress has been made to improve the vascular alterations, there is still no treatment to counteract the early neuro-glial perturbations in diabetic retinopathy. Diabetes is a complex metabolic disorder, characterized by chronic hyperglycemia along with dyslipidemia, hypoinsulinemia and hypertension. Increasing evidence points to inflammation as one key player in diabetes-associated retinal perturbations, however, the exact underlying molecular mechanisms are not yet fully understood. Interlinked molecular pathways, such as oxidative stress, formation of advanced glycation end-products and increased expression of vascular endothelial growth factor have received a lot of attention as they all contribute to the inflammatory response. In the current review, we focus on the involvement of inflammation in the pathophysiology of diabetic retinopathy with special emphasis on the functional relationships between glial cells and neurons. Finally, we summarize recent advances using novel targets to inhibit inflammation in diabetic retinopathy.

  13. Mechanisms controlling the oxygen consumption in experimentally induced hypochloremic alkalosis in calves.

    Science.gov (United States)

    Cambier, Carole; Clerbaux, Thierry; Amory, Hélène; Detry, Bruno; Florquin, Sandra; Marville, Vincent; Frans, Albert; Gustin, Pascal

    2002-01-01

    The study was carried out on healthy Friesian calves (n = 10) aged between 10 and 30 days. Hypochloremia and alkalosis were induced by intravenous administration of furosemide and isotonic sodium bicarbonate. The venous and arterial blood samples were collected repeatedly. 2,3-diphosphoglycerate (2,3-DPG), hemoglobin and plasmatic chloride concentrations were determined. The red blood cell chloride concentration was also calculated. pH, PCO2 and PO2 were measured in arterial and mixed venous blood. The oxygen equilibrium curve (OEC) was measured in standard conditions. The correspondence of the OEC to the arterial and mixed venous compartments was calculated, taking blood temperature, pH and PCO2 values into account. The oxygen exchange fraction (OEF%), corresponding to the degree of blood desaturation between the arterial and mixed venous compartments and the amount of oxygen released at the tissue level by 100 mL of blood (OEF Vol%) were calculated from the arterial and mixed venous OEC, combined with PO2 and hemoglobin concentration. Oxygen delivery (DO2) was calculated using the arterial oxygen content, the cardiac output measured by thermodilution, and the body weight of the animal. The oxygen consumption (VO2) was derived from the cardiac output, OEF Vol% and body weight values. Despite the plasma hypochloremia, the erythrocyte chloride concentration was not influenced by furosemide and sodium bicarbonate infusion. Due to the alkalosis-induced increase in the 2,3-DPG, the standard OEC was shifted to the right, allowing oxygen to dissociate from hemoglobin more rapidly. These changes opposed the increased affinity of hemoglobin for oxygen induced by alkalosis. Moreover, respiratory acidosis, hemoconcentration, and the slight decrease in the partial oxygen pressure in mixed venous blood (Pvo2) tended to improve the OEF Vol% and maintain the oxygen consumption in a physiological range while the cardiac output, and the oxygen delivery were significantly decreased

  14. Curcumin-induced inhibition of cellular reactive oxygen species generation: novel therapeutic implications.

    Science.gov (United States)

    Balasubramanyam, M; Koteswari, A Adaikala; Kumar, R Sampath; Monickaraj, S Finny; Maheswari, J Uma; Mohan, V

    2003-12-01

    There is evidence for increased levels of circulating reactive oxygen species (ROS) in diabetics, as indirectly inferred by the findings of increased lipid peroxidation and decreased antioxidant status. Direct measurements of intracellular generation of ROS using fluorescent dyes also demonstrate an association of oxidative stress with diabetes. Although phenolic compounds attenuate oxidative stress-related tissue damage, there are concerns over toxicity of synthetic phenolic antioxidants and this has considerably stimulated interest in investigating the role of natural phenolics in medicinal applications. Curcumin (the primary active principle in turmeric, Curcuma longa Linn.) has been claimed to represent a potential antioxidant and antiinflammatory agent with phytonutrient and bioprotective properties. However there are lack of molecular studies to demonstrate its cellular action and potential molecular targets. In this study the antioxidant effect of curcumin as a function of changes in cellular ROS generation was tested. Our results clearly demonstrate that curcumin abolished both phorbol-12 myristate-13 acetate (PMA) and thapsigargin-induced ROS generation in cells from control and diabetic subjects. The pattern of these ROS inhibitory effects as a function of dose-dependency suggests that curcumin mechanistically interferes with protein kinase C (PKC) and calcium regulation. Simultaneous measurements of ROS and Ca2+ influx suggest that a rise in cytosolic Ca2+ may be a trigger for increased ROS generation. We suggest that the antioxidant and antiangeogenic actions of curcumin, as a mechanism of inhibition of Ca2+ entry and PKC activity, should be further exploited to develop suitable and novel drugs for the treatment of diabetic retinopathy and other diabetic complications.

  15. Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion

    Energy Technology Data Exchange (ETDEWEB)

    Kyriacou, P A [School of Engineering and Mathematical Sciences, City University, London EC1V 0HB (United Kingdom); Shafqat, K [School of Engineering and Mathematical Sciences, City University, London EC1V 0HB (United Kingdom); Pal, S K [St Andrew' s Centre for Plastic Surgery and Burns, Broomfield Hospital, Chelmsford, CM1 7ET (United Kingdom)

    2007-10-15

    Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO{sub 2}) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO{sub 2}) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO{sub 2} sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures

  16. Radiation retinopathy after external-beam irradiation: Analysis of time-dose factors

    International Nuclear Information System (INIS)

    Parsons, J.T.; Bova, F.J.; Mendenhall, W.M.

    1994-01-01

    To investigate the risk of radiation-induced retinopathy according to total radiation dose and fraction size, based on both retorspective and prospectively collected data. Between October 1964 and May 1989, 68 retinae in 64 patients received fractionated external-beam irradiation during the treatment of primary extracranial head and neck tumors. All patients had a minimum of 3 years of ophthalmologic follow-up (range, 3 to 26 years; mean, 9 years; median, 8 years). Twenty-seven eyes in 26 patients developed radiation retinopathy resulting in visual acuity of 20/200 or worse. The mean and median times to the onset of symptoms attributable to retinal ischemia were 2.8 and 2.5 years, respectively. Fourteen of the injured eyes developed rubeosis iridis and/or neovascular glaucoma. Radiation retinopathy was not observed at doses below 45 Gy, but increased steadily in incidence at doses ≥45Gy. In the range of doses between 45 and 55 Gy, there was an increased risk of injury among patients who received doses per fraction of ≥1.9Gy (p - .09). There was also a trend toward increased risk of injury among patients who received chemotherapy (two of two vs. four of ten in the 45-51 Gy range; p - .23). The lowest dose associated with retinopathy was 45 Gy delivered to a diabetic patient by twice-a-day fractionation. The data did not suggest an increased risk of radiation retinopathy with increasing age. The current study suggests the importance of total dose as well as dose per fraction, and adds support to a small body of literature suggesting that patients with diabetes mellitus or who receive chemotherapy are at increased risk of injury. A sigmoid dose-response curve is constructed from our current data and data from the literature. 36 refs., 5 figs., 4 tabs

  17. SERUM MAGNESIUM, LIPID PROFILE AND GLYCATED HAEMOGLOBIN IN DIABETIC RETINOPATHY

    Directory of Open Access Journals (Sweden)

    Sunanda Vusikala

    2016-07-01

    Full Text Available BACKGROUND Diabetic retinopathy is one of the important microvascular complications of diabetes mellitus of long duration. Alterations in trace metals like magnesium and lipid profile was observed in diabetic retinopathy with hyperglycaemic status. AIM The study was taken up to assess the role of magnesium, lipid profile and glycated haemoglobin in diabetic retinopathy. MATERIALS AND METHODS A total of 80 subjects between 40-65 years were included in the study. Group 1 includes 20 age and sex matched healthy controls. Group 2 includes 30 cases of Diabetes mellitus without retinopathy. Group 3 includes 30 cases of Diabetes mellitus with retinopathy. RESULTS Magnesium was found to be significantly low in the diabetic group with retinopathy. Serum cholesterol and triglycerides were significantly elevated in the diabetic group with retinopathy. Fasting and Postprandial plasma glucose and glycated haemoglobin (HbA1c levels confirmed the glycaemic status of each of the groups. CONCLUSIONS Hypomagnesemia, hypercholesterolaemia, hypertriglyceridemia was observed in diabetic retinopathy along with increased levels of glycated haemoglobin in our study.

  18. Expression and function of Delta-like ligand 4 in a rat model of retinopathy of prematurity

    Institute of Scientific and Technical Information of China (English)

    Shaoyang Shi; Xun Li; You Li; Cunwen Pei; Hongwei Yang; Xiaolong Chen

    2013-01-01

    The Delta-like ligand 4/Notch signaling pathway was shown to participate in the process of retinal development and angiogenesis. However, the function of the Delta-like ligand 4/Notch signaling pathway in retinopathy of prematurity requires further study. Retinopathy of prematurity was induced in 5-day-old Sprague-Dawley rats exposed to hyperoxia for 7 days, and then returned to room air. Reverse transcription-PCR and western blot revealed that Delta-like ligand 4 levels decreased at postnatal day 12 and increased at postnatal day 17 in retinopathy of prematurity rats. Flat-mounted adenosine diphosphatase stained retina and hematoxylin-eosin stained retinal tissue slices showed that the clock hour scores and the nuclei counts in retinopathy of prematurity rats were significantly different compared to normal control rats. After retinopathy of prematurity rats were intravitreally injected with Delta-like ligand 4 monoclonal antibody to inhibit the Delta-like ligand 4/Notch signaling pathway, there was a significant increase in the severity of retinal neovascularization (clock hours) in the intravitreally injected eyes. The nuclei count was highly correlated with the clock hour score. These results suggest that Delta-like ligand 4/Notch signaling plays an essential role in the process of physiological and pathological angiogenesis in the retina.

  19. Regulation of singlet oxygen-induced apoptosis by cytosolic NADP+-dependent isocitrate dehydrogenase.

    Science.gov (United States)

    Kim, Sun Yee; Lee, Su Min; Tak, Jean Kyoung; Choi, Kyeong Sook; Kwon, Taeg Kyu; Park, Jeen-Woo

    2007-08-01

    Singlet oxygen is a highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules and it also promotes deleterious processes such as cell death. Recently, we demonstrated that the control of redox balance and the cellular defense against oxidative damage are the primary functions of cytosolic NADP(+)-dependent isocitrate dehydrogenase (IDPc) through supplying NADPH for antioxidant systems. In this report, we demonstrate that modulation of IDPc activity in HL-60 cells regulates singlet oxygen-induced apoptosis. When we examined the protective role of IDPc against singlet oxygen-induced apoptosis with HL-60 cells transfected with the cDNA for mouse IDPc in sense and antisense orientations, a clear inverse relationship was observed between the amount of IDPc expressed in target cells and their susceptibility to apoptosis. The results suggest that IDPc plays an important protective role in apoptosis of HL-60 cells induced by singlet oxygen.

  20. Simultaneous Fluorescein Angiography and Spectral Domain Optical Coherence Tomography Correlate Retinal Thickness Changes to Vascular Abnormalities in an In Vivo Mouse Model of Retinopathy of Prematurity

    Directory of Open Access Journals (Sweden)

    Olachi J. Mezu-Ndubuisi

    2017-01-01

    Full Text Available Background. Retinopathy of prematurity (ROP is a condition of abnormal retinal vascular development (RVD in premature infants. Fluorescein angiography (FA has depicted phases (early, mid, late, and mature of RVD in oxygen-induced retinopathy (OIR mice. We sought to establish the relationship between retinal structural and vascular changes using simultaneous FA and spectral domain optical coherence tomography (SD-OCT. Method. 63 mice were exposed to 77% oxygen at postnatal day 7 (P7 for 5 days, while 63 mice remained in room air (RA. Total retinal thickness (TRT, inner retinal thickness (IRT, and outer retinal thickness (ORT were calculated at early (P19, mid (P24, late (P32, and mature (P47 phases of RVD. Results. TRT was reduced in OIR (162.66 ± 17.75 μm, n=13 compared to RA mice at P19 (197.57 ± 3.49 μm, n=14, P24, P32, and P49 (P0.05. IRT was reduced in OIR (71.60 ± 17.14 μm compared to RA (103.07 ± 3.47 μm mice at P19 and all ages (P<0.0001. Conclusion. We have shown the spatial and temporal relationship between retinal structure and vascular development in OIR. Significant inner retinal thinning in OIR mice persisted despite revascularization of the capillary network; further studies will elucidate its functional implications in ROP.

  1. Radiation Retinopathy Associated with Central Retinal Vein Occlusion

    Institute of Scientific and Technical Information of China (English)

    Yan; Liu; FengWen

    2007-01-01

    Purpose: To report a case of radiation retinopathy associated with central retinal vein occlusion.Methods: The clinical features and fundus fluorescein angiography of this case were analyzed.Results: The patient had been treated with radiotherapy for her nasopharyngeal carcinoma, and presented with sudden visual loss in the left eye. The funduscopic examination and fluorescein angiography showed the features of radiation retinopathy in both eyes, and central retinal vein occlusion in the left eye.Conclusions: Radiation retinopathy can be associated with central retinal vein occlusion in the same eye, and it seems that the endothelial cell loss caused by radiation retinopathy may lead to retinal vein occlusion.

  2. New Therapeutic Approaches in Diabetic Retinopathy

    Science.gov (United States)

    Vaziri, Kamyar; Schwartz, Stephen G.; Relhan, Nidhi; Kishor, Krishna S.; Flynn Jr, Harry W.

    2015-01-01

    Diabetic retinopathy is a common microvascular complication of diabetes mellitus. It affects a substantial proportion of US adults over age 40. The condition is a leading cause of visual loss. Much attention has been given to expanding the role of current treatments along with investigating various novel therapies and drug delivery methods. In the treatment of diabetic macular edema (DME), intravitreal pharmacotherapies, especially anti-vascular endothelial growth factor (anti-VEGF) agents, have gained popularity. Currently, anti-VEGF agents are often used as first-line agents in center-involved DME, with recent data suggesting that among these agents, aflibercept leads to better visual outcomes in patients with worse baseline visual acuities. While photocoagulation remains the standard treatment for proliferative diabetic retinopathy (PDR), recent FDA approvals of ranibizumab and aflibercept in the management of diabetic retinopathy associated with DME may suggest a potential for pharmacologic treatments of PDR as well. Novel therapies, including small interfering RNAs, chemokines, kallikrein-kinin inhibitors, and various anti-angiogenic agents, are currently being evaluated for the management of diabetic retinopathy and DME. In addition to these strategies, novel drug delivery methods such as sustained-release implants and refillable reservoir implants are either under active evaluation or have recently gained FDA approval. This review provides an update on the novel developments in the treatment of diabetic retinopathy. PMID:26676668

  3. Epigenetic Modifications and Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Renu A. Kowluru

    2013-01-01

    Full Text Available Diabetic retinopathy remains one of the most debilitating chronic complications, but despite extensive research in the field, the exact mechanism(s responsible for how retina is damaged in diabetes remains ambiguous. Many metabolic pathways have been implicated in its development, and genes associated with these pathways are altered. Diabetic environment also facilitates epigenetics modifications, which can alter the gene expression without permanent changes in DNA sequence. The role of epigenetics in diabetic retinopathy is now an emerging area, and recent work has shown that genes encoding mitochondrial superoxide dismutase (Sod2 and matrix metalloproteinase-9 (MMP-9 are epigenetically modified, activates of epigenetic modification enzymes, histone lysine demethylase 1 (LSD1, and DNA methyltransferase are increased, and the micro RNAs responsible for regulating nuclear transcriptional factor and VEGF are upregulated. With the growing evidence of epigenetic modifications in diabetic retinopathy, better understanding of these modifications has potential to identify novel targets to inhibit this devastating disease. Fortunately, the inhibitors and mimics targeted towards histone modification, DNA methylation, and miRNAs are now being tried for cancer and other chronic diseases, and better understanding of the role of epigenetics in diabetic retinopathy will open the door for their possible use in combating this blinding disease.

  4. Relationship between retinopathy and cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Colakoglu Onder; Taskiran Bengur; Dayi Selcuk; Sozmen Bulent; Unsal Belkis; Maden Ahmet; Pasa Eser; Aslan S. Leyla

    2005-01-01

    AIM: To evaluate ophthalmic disorders with special attention to retinopathy in cirrhotic patients. Vitamin A deficiency-related ophthalmopathy, xerophthalmia, and color blindness may be documented in cirrhosis due to various etiologies. Retinopathy is an obscure feature of cirrhosis. METHODS: Thirty-two cirrhotic patients, who were followed up by Clinics of Gastroenterology, Izmir Ataturk Teaching and Research Hospital, were enrolled to the study. Associated systemic diseases such as diabetes mellitus and hypertension were excluded. Thirty-two healthy volunteers took part as the control subjects. All participants had ophthalmologic examination in the same hospital. RESULTS: Five (15.6%) of the cirrhotic subjects had soft exudate in the retina. None of the control subjects had retinopathy (P<0.05). Intraocular pressure (IOP) measured for both eyes were also significantly lower in the cirrhotics (P<0.05 vs P = 0.01). There were no statistically significant differences between the two groups in terms of other ophthalmic pathologies. The ophthalmic findings did not show up any differences according to the etiology of cirrhosis. CONCLUSION: Soft exudates may develop in cirrhotic patients probably due to loss of synthetic function of liver and hemodynamic effects of portal hypertension. Retinopathy must be sought in cirrhosis because of its severe morbidity.

  5. Diabetic retinopathy screening using deep neural network.

    Science.gov (United States)

    Ramachandran, Nishanthan; Hong, Sheng Chiong; Sime, Mary J; Wilson, Graham A

    2017-09-07

    There is a burgeoning interest in the use of deep neural network in diabetic retinal screening. To determine whether a deep neural network could satisfactorily detect diabetic retinopathy that requires referral to an ophthalmologist from a local diabetic retinal screening programme and an international database. Retrospective audit. Diabetic retinal photos from Otago database photographed during October 2016 (485 photos), and 1200 photos from Messidor international database. Receiver operating characteristic curve to illustrate the ability of a deep neural network to identify referable diabetic retinopathy (moderate or worse diabetic retinopathy or exudates within one disc diameter of the fovea). Area under the receiver operating characteristic curve, sensitivity and specificity. For detecting referable diabetic retinopathy, the deep neural network had an area under receiver operating characteristic curve of 0.901 (95% confidence interval 0.807-0.995), with 84.6% sensitivity and 79.7% specificity for Otago and 0.980 (95% confidence interval 0.973-0.986), with 96.0% sensitivity and 90.0% specificity for Messidor. This study has shown that a deep neural network can detect referable diabetic retinopathy with sensitivities and specificities close to or better than 80% from both an international and a domestic (New Zealand) database. We believe that deep neural networks can be integrated into community screening once they can successfully detect both diabetic retinopathy and diabetic macular oedema. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

  6. "Oxygen with love" and diode laser treatment decreases comorbidity and avoidable blindness due to retinopathy of prematurity: results achieved in the past 12 years.

    Science.gov (United States)

    Garcia-Serrano, Jose Luis; Uberos Fernández, José; Anaya-Alaminos, Roberto; Jerez-Calero, Antonio; Padilla-Torres, José Francisco; Ramírez-Garcia, Maria Carmen; Piñar-Molina, Raquel

    2013-12-01

    To determine whether the "Oxygen with Love" (OWL) and diode laser treatment provided in a neonatal intensive care unit has reduced the risk of avoidable blindness caused by retinopathy of prematurity (ROP) over the past decade. A prospective observational cohort study was performed, in which 351 infants were examined for ROP. The inclusion conditions were as follows: preterm infants, birthweight birth between 1 Jan 2000 to 31 August 2012. From mid-2009, the OWL program was implemented and the ventilation protocols for such infants were amended. We tested whether the incidence of unfavorable structural outcomes of ROP had decreased following these changes. From 2004 to 2012, the survival rates of younger children increased (p rate falling from 11.81% to 3.9% (p rates of sepsis (p rates of sepsis, improvements in postnatal weight gain, and the use of diode laser treatment, has reduced the incidence of unfavorable structural outcomes of ROP. Copyright © 2013. Published by Elsevier B.V.

  7. Micronutrients and Diabetic Retinopathy A Systematic Review

    NARCIS (Netherlands)

    Lee, Chee-Tin Christine; Gayton, Emma L.; Beulens, Joline W. J.; Flanagan, Declan W.; Adler, Amanda I.

    Background: We have evaluated the evidence for the association between intake and blood levels of micronutrients and diabetic retinopathy. Treatment for diabetic retinopathy requires significant clinical input and specialist ophthalmologic care. Micronutrients, including vitamin C, vitamin E, and

  8. Ultra-wide-field imaging in diabetic retinopathy.

    Science.gov (United States)

    Ghasemi Falavarjani, Khalil; Tsui, Irena; Sadda, Srinivas R

    2017-10-01

    Since 1991, 7-field images captured with 30-50 degree cameras in the Early Treatment Diabetic Retinopathy Study were the gold standard for fundus imaging to study diabetic retinopathy. Ultra-wide-field images cover significantly more area (up to 82%) of the fundus and with ocular steering can in many cases image 100% of the fundus ("panretinal"). Recent advances in image analysis of ultra-wide-field imaging allow for precise measurements of the peripheral retinal lesions. There is a growing consensus in the literature that ultra-wide-field imaging improves detection of peripheral lesions in diabetic retinopathy and leads to more accurate classification of the disease. There is discordance among studies, however, on the correlation between peripheral diabetic lesions and diabetic macular edema and optimal management strategies to treat diabetic retinopathy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. The anti-ALS drug riluzole attenuates pericyte loss in the diabetic retinopathy of streptozotocin-treated mice

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jeong A. [Neural Injury Research Center, Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Chung, Yoo-Ri [Department of Ophthalmology, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Byun, Hyae-Ran [Neural Injury Research Center, Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Park, Hwangseo [Department of Bioscience and Biotechnology, Sejong University, Seoul (Korea, Republic of); Koh, Jae-Young, E-mail: jkko@amc.seoul.kr [Neural Injury Research Center, Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Yoon, Young Hee, E-mail: yhyoon@amc.seoul.kr [Department of Ophthalmology, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2017-01-15

    Loss of pericytes, considered an early hallmark of diabetic retinopathy, is thought to involve abnormal activation of protein kinase C (PKC). We previously showed that the anti-amyotrophic lateral sclerosis (ALS) drug riluzole functions as a PKC inhibitor. Here, we examined the effects of riluzole on pathological changes in diabetic retinopathy. Pathological endpoints examined in vivo included the number of pericytes and integrity of retinal vessels in streptozotocin (STZ)-induced diabetic mice. In addition, PKC activation and the induction of monocyte chemotactic protein (MCP1) were assessed in diabetic mice and in human retinal pericytes exposed to advanced glycation end product (AGE) or modified low-density lipoprotein (mLDL). The diameter of retinal vessels and the number of pericytes were severely reduced, and the levels of MCP1 and PKC were increased in STZ-induced diabetic mice. Administration of riluzole reversed all of these changes. Furthermore, the increased expression of MCP1 in AGE- or mLDL-treated cultured retinal pericytes was inhibited by treatment with riluzole or the PKC inhibitor GF109203X. In silico modeling showed that riluzole fits well within the catalytic pocket of PKC. Taken together, our results demonstrate that riluzole attenuates both MCP1 induction and pericyte loss in diabetic retinopathy, likely through its direct inhibitory effect on PKC. - Highlights: • The effects of riluzole were examined in streptozotocin-induced diabetic mice. • The diameter of retinal vessels and the number of pericytes were severely reduced. • The levels of MCP1 and PKC were increased, while riluzole reversed all changes. • Riluzole attenuated the level of MCP1 in AGE- or mLDL-treated retinal pericytes. • Riluzole attenuated both MCP1 induction and pericyte loss in diabetic retinopathy.

  10. The anti-ALS drug riluzole attenuates pericyte loss in the diabetic retinopathy of streptozotocin-treated mice

    International Nuclear Information System (INIS)

    Choi, Jeong A.; Chung, Yoo-Ri; Byun, Hyae-Ran; Park, Hwangseo; Koh, Jae-Young; Yoon, Young Hee

    2017-01-01

    Loss of pericytes, considered an early hallmark of diabetic retinopathy, is thought to involve abnormal activation of protein kinase C (PKC). We previously showed that the anti-amyotrophic lateral sclerosis (ALS) drug riluzole functions as a PKC inhibitor. Here, we examined the effects of riluzole on pathological changes in diabetic retinopathy. Pathological endpoints examined in vivo included the number of pericytes and integrity of retinal vessels in streptozotocin (STZ)-induced diabetic mice. In addition, PKC activation and the induction of monocyte chemotactic protein (MCP1) were assessed in diabetic mice and in human retinal pericytes exposed to advanced glycation end product (AGE) or modified low-density lipoprotein (mLDL). The diameter of retinal vessels and the number of pericytes were severely reduced, and the levels of MCP1 and PKC were increased in STZ-induced diabetic mice. Administration of riluzole reversed all of these changes. Furthermore, the increased expression of MCP1 in AGE- or mLDL-treated cultured retinal pericytes was inhibited by treatment with riluzole or the PKC inhibitor GF109203X. In silico modeling showed that riluzole fits well within the catalytic pocket of PKC. Taken together, our results demonstrate that riluzole attenuates both MCP1 induction and pericyte loss in diabetic retinopathy, likely through its direct inhibitory effect on PKC. - Highlights: • The effects of riluzole were examined in streptozotocin-induced diabetic mice. • The diameter of retinal vessels and the number of pericytes were severely reduced. • The levels of MCP1 and PKC were increased, while riluzole reversed all changes. • Riluzole attenuated the level of MCP1 in AGE- or mLDL-treated retinal pericytes. • Riluzole attenuated both MCP1 induction and pericyte loss in diabetic retinopathy.

  11. Effects of hyperbaric, normobaric and hypobaric oxygen supplementation on retinal vessels in newborn rats: a preliminary study.

    Science.gov (United States)

    Ricci, B

    1987-03-01

    An experimental study was conducted on eight litters of newborn rats to evaluate the effects of supplemental oxygen administration on the retinal vasculature. The animals and their mothers were kept inside a pressure chamber and treated for the first 5 days of life. On the sixth day, they were removed and kept for five more days under room air and normobaric conditions. Three litters received continuous flow oxygen at 80% at a compression pressure of +81 kPa, one litter oxygen at 80% at a pressure of -39.5 kPa atms and three other litters received oxygen at 80% under normobaric conditions. The eighth litter was treated with room air oxygen at a compression pressure of +81 kPa. A severe retinopathy with marked retinal neovascularization was seen only in the newborn animals of the litters that received oxygen supplementation under normobaric or hypobaric conditions. Retinal vessels showed no pathological changes in the litters treated with hyperbaric normoxia or hyperoxia. It is possible to hypothesize that the prolonged period of oxygen supplementation failed to produce harmful effects on the retinal vasculature because the moderate hyperbarism caused mild retinal and choroidal vasoconstriction thus preventing excessive oxygen transport to the inner retina from the choroid during hyperoxia without inducing structural damage to the retinal tissue.

  12. Association between human breast milk and retinopathy of prematurity.

    Science.gov (United States)

    Fonseca, Luciana Teixeira; Senna, Denise C; Eckert, Gabriela Unchalo; Silveira, Rita de Cássia; Procianoy, Renato Soibelmann

    2018-04-01

    To evaluate the possible protective effect of breast milk against retinopathy of prematurity by comparing the amount of breast milk received by patients who developed retinopathy of prematurity and those who did not and to determine both the required minimum amount of breast milk and the time of life during which neonates need to receive breast milk for this effect to be significant. Cohort study of newborns with a birth weight of prematurity of any degree was 31% (100 of 323 patients) and that of severe retinopathy of prematurity was of 9% (29 of 323 patients). The median amounts of breast milk received daily by patients with and without retinopathy of prematurity were 4.9 mL/kg (interquartile range, 0.3-15.4) and 10.2 mL/kg (1.5-25.5), respectively. The amount of breast milk received in the first 6 weeks of life was inversely associated with the incidence of both retinopathy of prematurity of any degree and severe retinopathy of prematurity in the univariate analyses. However, the statistical significance was maintained only during the sixth week of life in a per-period multivariate analysis controlling for confounding factors. Small amounts of breast milk are inadequate to prevent retinopathy of prematurity in premature newborns at risk for the disease.

  13. Sixteen-year incidence of diabetic retinopathy and proliferative diabetic retinopathy in a nationwide cohort of young Danish type 1 diabetic patients

    DEFF Research Database (Denmark)

    Broe, Rebecca; Rasmussen, Malin Lundberg; Peto, Tunde

    2013-01-01

    Design of study: Prospective cohort-study Purpose: The aim of this study was to assess long-term incidence of diabetic retinopathy (DR) and proliferative diabetic retinopathy (PDR) and associated risk factors in a Danish population-based cohort of young type 1 diabetic patients. Methods: Eighty...... percent of all Danish type 1 diabetic patients below the age of 18 (n=1033) were examined in 1986-89. In 1995, baseline retinopathy was graded and other risk factors were assessed in 324 patients (31.4% of the original cohort). Of these, 132 (40.7%) were re-examined at follow-up in 2011. At baseline two...... and diabetes duration. Results: The mean age and diabetes duration at baseline were 21.1±3.1 and 13.3±3.5 years, respectively. At baseline 31.8% had no retinopathy, 67.4% had non-PDR and 0.8% had PDR. At follow-up, the prevalence of diabetic retinopathy was 96.9%. Thirty-eight patients with no DR at baseline...

  14. Early diagnosis of diabetic retinopathy in primary care.

    Science.gov (United States)

    Jimenez-Baez, Maria Valeria; Marquez-Gonzalez, Horacio; Barcenas-Contreras, Rodolfo; Morales Montoya, Carlos; Espinosa-Garcia, Laura Fatima

    2015-01-01

    To evaluate the impact of a strategy for early detection of diabetic retinopathy in patients with type 2 diabetes mellitus (DMT2) in Quintana Roo, México. Study transversal, observational, prospective, analytical, eight primary care units from Mexican Social Security Institute in the northern delegation of the State of Quintana Roo, Mexico were included. A program for early detection of diabetic retinopathy (DR) in adult 376,169 was designed. Were diagnosed 683 cases of type 2 diabetes, in 105 patients randomized was conducted to direct ophthalmoscopy were subjected to a secondary hospital were assigned. Will determine the degree of diabetic retinopathy and macular edema was performed. In population were 55.2% female, mean age 48+11.1 years, 23.8 % had some degree of DR, 28.0% with mild non- proliferative diabetic retinopathy 48.0 % moderate 16.0% and severe and 8.0% showed proliferative diabetic retinopathy. Those over age 30 are 2.8 times more risk of developing DR, OR= 2.8; 95%CI: 0.42-18.0, and OR= 1.7; 95%CI: 1.02-2.95 women. The implementation of programs aimed at the early detection of debilitating conditions such as diabetic retinopathy health impact beneficiaries, effective links between primary care systems and provide second level positive health outcomes for patient diseases.

  15. Retinopathy in an obesity WHO III cohort: prevalence and risk factors.

    Science.gov (United States)

    Mattern, Juri; Lammert, Alexander; Otto, Mirko; Hammes, Hans-Peter

    2017-11-01

    To assess retinopathy and its risk factors in an obesity WHO III cohort. In the Mannheim Obesity Study , 277 subjects with obesity WHO III aged 18-64 years were examined in a cross-sectional approach. Screening for retinopathy was performed using 3-field retinal photography. Endothelial function was assessed using arteriole-to-venule ratio and flicker light analysis. Subjects with and without retinopathy were analysed for anthropometry, metabolic, vascular and renal parameters. Retinopathy was found in 18 of the 277 subjects (6.5%). Prevalence of retinopathy was 16.7% in subjects with and 3.4% in subjects without diabetes mellitus. Between subjects with and without retinopathy there were significant differences in diabetes prevalence (61.1% vs 21.7%, pretinopathy (OR 8.3, p=0.049, 95% CI 1.01 to 67.49), whereas risk for retinopathy decreased by nearly 50% (OR 0.54, p=0.032, 95% CI 0.30 to 0.95) with each percentage increase in venous dilatation in response to flicker light. Retinopathy prevalence in our obesity WHO III cohort is low. Presence of diabetes mellitus is the most important risk factor for retinopathy. Preserved venular function indicates protection from retinopathy. NCT00770276, Results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Role of frequency doubling technology perimetry in screening of diabetic retinopathy.

    Directory of Open Access Journals (Sweden)

    Parikh Rajul

    2006-01-01

    Full Text Available Purpose: To study the ability of frequency-doubling technology perimetry (FDT to detect sight-threatening diabetic retinopathy. Method: Fifty-eight eyes of fifty-eight patients with established diagnosis of diabetes mellitus with diabetic retinopathy, fifty-five eyes of fifty-five diabetic patients without retinopathy, and forty-one eyes of forty-one normals underwent FDT and dilated stereo-biomicroscopic fundus examination. The sensitivity and specificity of FDT in identification of "sight-threatening retinopathy" (severe and very severe nonproliferative diabetic retinopathy and proliferative diabetic retinopathy and clinically significant macular edema (CSME were determined. Results: For the detection of sight-threatening retinopathy, two abnormal adjacent points depressed to any level on the 20-1 screening program had a sensitivity of 90.5% and specificity of 97.6%. At (assuming a 10% prevalence of sight-threatening retinopathy in a diabetic clinic, two abnormal adjacent points anywhere in the field depressed to any level has a positive predictive value (PPV of 48% with a negative predictive value of 98.8%. Sensitivity and specificity for the detection of CSME was poor. Conclusions: The 20-1 screening program of the FDT is useful in the detection of sight-threatening diabetic retinopathy (PPV 48%. A normal 20-1 test rules out sight-threatening retinopathy. FDT was not useful in the detection of CSME.

  17. UPP mediated Diabetic Retinopathy via ROS/PARP and NF-κB inflammatory factor pathways.

    Science.gov (United States)

    Luo, D-W; Zheng, Z; Wang, H; Fan, Y; Chen, F; Sun, Y; Wang, W-J; Sun, T; Xu, X

    2015-01-01

    Diabetic retinopathy (DR) is a leading cause of blindness in adults at working age. Human diabetic retinopathy is characterized by the basement membrane thick, pericytes loss, microaneurysms formation, retina neovascularization and vitreous hemorrhage. To investigate whether UPP activated ROS/PARP and NF-κB inflammatory factor pathways in Diabetic Retinopathy, human retinal endothelial cells (HRECs) and rats with streptozotocin-induced diabetes were used to determine the effect of UPP on ROS generation, cell apoptosis, mitochondrial membrane potential (ΔΨm) and inflammatory factor protein expression, through flow cytometry assay, immunohistochemistry, Real-time PCR, Western blot analysis and ELISA. The levels of ROS and apoptosis and the expressions of UPP (Ub and E3) and inflammatory factor protein were increased in high glucose-induced HRECs and retina of diabetic rats, while ΔΨm was decreased. The UPP inhibitor and UbshRNA could attenuate these effects through inhibiting the pathway of ROS/PARP and the expression of NF-κB inflammatory factors, and the increased UPP was a result of high glucose-induced increase of ROS generation and NF-κBp65 expression, accompanied with the decrease of ΔΨm. Clinical study showed the overexpression of UPP and detachment of epiretinal membranes in proliferative DR (PDR) patients. It has been indicated that the pathogenic effect of UPP on DR was involved in the increase of ROS generation and NF-κB expression, which associated with the ROS/PARP and NF-κB inflammatory factor pathways. Our study supports a new insight for further application of UPP inhibitor in DR treatment.

  18. Retinopathy of prematurity

    International Nuclear Information System (INIS)

    Benavides Vargas, Ana Maria

    2013-01-01

    Retinopathy of prematurity has been the leading cause of childhood blindness. Early and effective screening has helped to diagnose the visual target of an infant by the difference between growing up with a disability or not. A joint effort between ophthalmologists and neonatologists is proposed to control this disease, ensuring success. An appropriate, early, effective and timely treatment has been the laser and cryotherapy like good choices for the neonate to prevent disease progression. Evaluation of screening program, to determine the incidence, compare statistics variables have been measures as other medical pathologies should be encouraged as research topics. A decrease in the incidence of retinopathy of prematurity is expected, controlling the risk factors during the child's stay in intrahospital neonatal unit [es

  19. Optimal oxygen saturation in premature infants

    Directory of Open Access Journals (Sweden)

    Meayoung Chang

    2011-09-01

    Full Text Available There is a delicate balance between too little and too much supplemental oxygen exposure in premature infants. Since underuse and overuse of supplemental oxygen can harm premature infants, oxygen saturation levels must be monitored and kept at less than 95% to prevent reactive oxygen species-related diseases, such as retinopathy of prematurity and bronchopulmonary dysplasia. At the same time, desaturation below 80 to 85% must be avoided to prevent adverse consequences, such as cerebral palsy. It is still unclear what range of oxygen saturation is appropriate for premature infants; however, until the results of further studies are available, a reasonable target for pulse oxygen saturation (SpO2 is 90 to 93% with an intermittent review of the correlation between SpO2 and the partial pressure of arterial oxygen tension (PaO2. Because optimal oxygenation depends on individuals at the bedside making ongoing adjustments, each unit must define an optimal target range and set alarm limits according to their own equipment or conditions. All staff must be aware of these values and adjust the concentration of supplemental oxygen frequently.

  20. The Role of Microglia in Diabetic Retinopathy: Inflammation, Microvasculature Defects and Neurodegeneration

    Science.gov (United States)

    Altmann, Christine

    2018-01-01

    Diabetic retinopathy is a common complication of diabetes mellitus, which appears in one third of all diabetic patients and is a prominent cause of vision loss. First discovered as a microvascular disease, intensive research in the field identified inflammation and neurodegeneration to be part of diabetic retinopathy. Microglia, the resident monocytes of the retina, are activated due to a complex interplay between the different cell types of the retina and diverse pathological pathways. The trigger for developing diabetic retinopathy is diabetes-induced hyperglycemia, accompanied by leukostasis and vascular leakages. Transcriptional changes in activated microglia, mediated via the nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) and extracellular signal–regulated kinase (ERK) signaling pathways, results in release of various pro-inflammatory mediators, including cytokines, chemokines, caspases and glutamate. Activated microglia additionally increased proliferation and migration. Among other consequences, these changes in microglia severely affected retinal neurons, causing increased apoptosis and subsequent thinning of the nerve fiber layer, resulting in visual loss. New potential therapeutics need to interfere with these diabetic complications even before changes in the retina are diagnosed, to prevent neuronal apoptosis and blindness in patients. PMID:29301251

  1. Pregnancy-induced increase in circulating IGF-I is associated with progression of diabetic retinopathy in women with type 1 diabetes

    DEFF Research Database (Denmark)

    Nielsen, Lene Ringholm; Vestgaard, Marianne; Laugesen, Caroline S

    2011-01-01

    To evaluate the influence of Insulin-like Growth factor-I (IGF-I) and Placental Growth Hormone (GH) on progression of diabetic retinopathy during pregnancy in women with type 1 diabetes.......To evaluate the influence of Insulin-like Growth factor-I (IGF-I) and Placental Growth Hormone (GH) on progression of diabetic retinopathy during pregnancy in women with type 1 diabetes....

  2. Effects of normobaric versus hyperbaric oxygen on cell injury induced by oxygen and glucose deprivation in acute brain slices

    OpenAIRE

    Laurent Chazalviel; Jean-Eric Blatteau; Nicolas Vallée; Jean-Jacques Risso; Stéphane Besnard; Jacques H Abraini

    2016-01-01

    Normobaric oxygen (NBO) and hyperbaric oxygen (HBO) are emerging as a possible co-treatment of acute ischemic stroke. Both have been shown to reduce infarct volume, to improve neurologic outcome, to promote endogenous tissue plasminogen activator-induced thrombolysis and cerebral blood flow, and to improve tissue oxygenation through oxygen diffusion in the ischemic areas, thereby questioning the interest of HBO compared to NBO. In the present study, in order to investigate and compare the oxy...

  3. Induction of ischemic tolerance as a promising treatment against diabetic retinopathy

    Institute of Scientific and Technical Information of China (English)

    Ruth E.Rosenstein; Diego C.Fernandez

    2014-01-01

    Diabetic retinopathy is a leading cause of acquired blindness, and it is the most common ischemic disorder of the retina. Available treatments are not very effective. Efforts to inhibit diabetic reti-nopathy have focused either on highly speciifc therapeutic approaches for pharmacologic targets or using genetic approaches to change expression of certain enzymes. However, it might be wise to choose innovative treatment modalities that act by multiple potential mechanisms. The resis-tance to ischemic injury, or ischemic tolerance, can be transiently induced by prior exposure to a non-injurious preconditioning stimulus. A complete functional and histologic protection against retinal ischemic damage can be achieved by previous preconditioning with non-damaging isch-emia. In this review, we will discuss evidence that supports that ischemic conditioning could help avert the dreaded consequences that results from retinal diabetic damage.

  4. Role of phospholipases A2 in diabetic retinopathy: in vitro and in vivo studies.

    Science.gov (United States)

    Lupo, Gabriella; Motta, Carla; Giurdanella, Giovanni; Anfuso, Carmelina Daniela; Alberghina, Mario; Drago, Filippo; Salomone, Salvatore; Bucolo, Claudio

    2013-12-01

    Diabetic retinopathy is one of the leading causes of blindness and the most common complication of diabetes with no cure available. We investigated the role of phospholipases A2 (PLA2) in diabetic retinopathy using an in vitro blood-retinal barrier model (BRB) and an in vivo streptozotocin (STZ)-induced diabetic model. Mono- and co-cultures of endothelial cells (EC) and pericytes (PC), treated with high or fluctuating concentrations of glucose, to mimic the diabetic condition, were used. PLA2 activity, VEGF and PGE2 levels and cell proliferation were measured, with or without PLA2 inhibition. Diabetes was induced in rats by STZ injection and PLA2 activity along with VEGF, TNFα and ICAM-1 levels were measured in retina. High or fluctuating glucose induced BRB breakdown, and increased PLA2 activity, PGE2 and VEGF in EC/PC co-cultures; inhibition of PLA2 in mono- or co-cultures treated with high or fluctuating glucose dampened PGE2 and VEGF production down to the levels of controls. High or fluctuating glucose increased EC number and reduced PC number in co-cultures; these effects were reversed after transfecting EC with small interfering RNA targeted to PLA2. PLA2 and COX-2 protein expressions were significantly increased in microvessels from retina of diabetic rats. Diabetic rats had also high retinal levels of VEGF, ICAM-1 and TNFα that were reduced by treatment with a cPLA2 inhibitor. In conclusion, the present findings indicate that PLA2 upregulation represents an early step in glucose-induced alteration of BRB, possibly upstream of VEGF; thus, PLA2 may be an interesting target in managing diabetic retinopathy. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Is there any correlation between vitamin D insufficiency and diabetic retinopathy?

    Institute of Scientific and Technical Information of China (English)

    Shokoufeh; Bonakdaran; Nasser; Shoeibi

    2015-01-01

    AIM: To determine a relation between vitamin D level,which is an inhibitor of angiogenesis, and diabetic retinopathy and its risk factorsMETHODS: In a clinic-based cross sectional study two hundred and thirty-five type 2 diabetic patients older than 20 y were selected. Patients were classified according to ophthalmologic examination as following:no diabetic retinopathy(NDR)(n =153), non-proliferative diabetic retinopathy(NPDR)(n =64) and proliferative diabetic retinopathy(PDR)(n =18). Study subjects were tested for fasting blood glucose, glycated hemoglobin A1C(Hb A1C), lipid profile, microalbuminuria, Hs CRP,IGF1, insulin(in patients without history of insulin taking)and 25 hydroxy vitamin D [25(OH) D] levels. Vitamin D insufficiency was defined according to 25(OH) D level less than 30 ng/m L. The relationship between diabetic retinopathy and serum 25(OH) D insufficiency was evaluated.RESULTS: The prevalence of diabetic retinopathy was34.8% in our patients. Long duration of diabetes,hypertension, poor glycemic control, diabetic nephropathy, hyperinsulinemia and insulin resistance were risk factors for diabetic retinopathy but 25(OH) D level was not significant different between NDR, NPDR and PDR groups. Correlation between 25(OH) D level and other known risk factors of diabetic retinopathy was not significant.CONCLUSION: This study did not find any association between diabetic retinopathy and its severity and vitamin D insufficiency. Vitamin D insufficiency is not related to risk factors of diabetic retinopathy.

  6. Mechanisms of PEDF-mediated protection against reactive oxygen species damage in diabetic retinopathy and neuropathy.

    Science.gov (United States)

    Elahy, Mina; Baindur-Hudson, Swati; Cruzat, Vinicius F; Newsholme, Philip; Dass, Crispin R

    2014-09-01

    Pigment epithelium-derived factor (PEDF) is a pluripotent glycoprotein belonging to the serpin family. PEDF can stimulate several physiological processes such as angiogenesis, cell proliferation, and survival. Oxidative stress plays an important role in the occurrence of diabetic retinopathy (DR), which is the major cause of blindness in young diabetic adults. PEDF plays a protective role in DR and there is accumulating evidence of the neuroprotective effect of PEDF. In this paper, we review the role of PEDF and the mechanisms involved in its antioxidative, anti-inflammatory, and neuroprotective properties. © 2014 Society for Endocrinology.

  7. Diabetic retinopathy: A predictor of coronary artery disease

    Directory of Open Access Journals (Sweden)

    Fawzia El Demerdash

    2012-06-01

    Conclusion: Diabetic retinopathy is a good predictor of coronary artery disease that exceeds the conventional risk factors. Diabetics with retinopathy would benefit from early coronary angiography and diabetic retinocoronary clinics are warranted.

  8. Prevalence of diabetic retinopathy in various ethnic groups: a worldwide perspective.

    Science.gov (United States)

    Sivaprasad, Sobha; Gupta, Bhaskar; Crosby-Nwaobi, Roxanne; Evans, Jennifer

    2012-01-01

    The alarming rise in diabetes prevalence is a global public health and economic problem. Diabetic retinopathy is the most common complication of diabetes and the leading cause of blindness among working-age populations in the Western world. Screening and prompt treatment of diabetic retinopathy are not top priorities in many regions of the world, because the impacts of other causes of preventable blindness remain an issue. Ethnicity is a complex, independent risk factor for diabetic retinopathy. Observations from white populations cannot be extrapolated fully to other ethnic groups. The prevalence of diabetic retinopathy, sight-threatening diabetic retinopathy, and clinically significant macular edema are higher in people of South Asian, African, Latin American, and indigenous tribal descent compared to the white population. Although all ethnic groups are susceptible to the established risk factors of diabetic retinopathy-such as length of exposure and severity of hyperglycemia, hypertension, and hyperlipidemia-ethnic-specific risk factors also may influence these rates. Such risk factors may include differential susceptibility to conventional risk factors, insulin resistance, differences in anthropometric measurements, truncal obesity, urbanization, variations in access to healthcare systems, genetic susceptibility, and epigenetics. The rates of nonproliferative diabetic retinopathy appear to be declining in the United States, supporting the observation that better medical management of diabetes and prompt treatment of sight-threatening diabetic retinopathy substantially improve the long-term diabetic retinopathy incidence; studies from other parts of the world are limited and do not mirror this finding, however. We examine the ethnicity and region-based prevalence of diabetic retinopathy around the world and highlight the need to reinforce ethnicity-based screening and treatment thresholds in diabetic retinopathy. Copyright © 2012 Elsevier Inc. All rights

  9. Screening for diabetic retinopathy | Rice | Continuing Medical ...

    African Journals Online (AJOL)

    Good glucose control and the treatment of hypertension and hyperlipidaemia remain the key strategies in preventing diabetic retinopathy and its progression. Unfortunately, some degree of retinopathy will eventually develop in almost all type 1 diabetics and over 60% of type 2 diabetics over a 20-year period.

  10. DIABETIC RETINOPATHY AND THE EFFECT OF PREGNANCY

    Directory of Open Access Journals (Sweden)

    SYED ALWI SAR

    2010-01-01

    Full Text Available Pregnancy is associated with increased risk of development and progression of diabetic retinopathy (DR. Although pregnancy does not have any long term effect on DR, progression of retinopathy changes occur in 50%-70% of cases. The greatest risk of worsening occurs during the second trimester and persists as long as 12 months postpartum. The other factors found to be associated with its progression include duration of the diabetes, severity of retinopathy at conception, hyperglycaemic control, anaemia and progression of coexisting hypertension. Because of the increased risk of progression of the disease inpregnancy, conception should be delayed till the ocular disease is treated and stabilized and laser photocoagulation should be promptly instituted in all cases of severe non-proliferative retinopathy and should not be delayed till the patient develops early proliferative changes. Good diabetic control before and during pregnancy can help prevent this increase in the progression and serious vision loss.

  11. Increased frequency of retinopathy of prematurity over the last decade and significant regional differences.

    Science.gov (United States)

    Holmström, Gerd; Tornqvist, Kristina; Al-Hawasi, Abbas; Nilsson, Åsa; Wallin, Agneta; Hellström, Ann

    2018-03-01

    Retinopathy of prematurity (ROP) causes childhood blindness globally in prematurely born infants. Although increased levels of oxygen supply lead to increased survival and reduced frequency of cerebral palsy, increased incidence of ROP is reported. With the help of a Swedish register for ROP, SWEDROP, national and regional incidences of ROP and frequencies of treatment were evaluated from 2008 to 2015 (n = 5734), as well as before and after targets of provided oxygen changed from 85-89% to 91-95% in 2014. Retinopathy of prematurity (ROP) was found in 31.9% (1829/5734) of all infants with a gestational age (GA) of <31 weeks at birth and 5.7% of the infants (329/5734) had been treated for ROP. Analyses of the national data revealed an increased incidence of ROP during the 8-year study period (p = 0.003), but there was no significant increase in the frequency of treatment. There were significant differences between the seven health regions of Sweden, regarding both incidence of ROP and frequency of treatment (p < 0.001). Comparison of regional data before and after the new oxygen targets revealed a significant increase in treated ROP in one region [OR: 2.24 (CI: 1.11-4.49), p = 0.024] and a borderline increase in one other [OR: 3.08 (CI: 0.99-9.60), p = 0.052]. The Swedish national ROP register revealed an increased incidence of ROP during an 8-year period and significant regional differences regarding the incidence of ROP and frequency of treatment. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  12. Solar Retinopathy: A Multimodal Analysis

    Directory of Open Access Journals (Sweden)

    Claudia Bruè

    2013-01-01

    Full Text Available Purpose. Solar retinopathy is a rare clinical disturbance, for which spectral-domain optical coherence tomography (SD-OCT findings are not always consistent. We report on two cases of solar retinopathy and discuss its differential diagnosis. Methods. This is an observational case study. Results. A 12-year-old female was referred to ophthalmology for bilateral scotoma. Visual acuity was 20/50 in both eyes. Fundus examination was unremarkable, except for slight yellowish material in the central macula, bilaterally. SD-OCT revealed juxtafoveal microcystic cavities in the outer retina, interruption of the external limiting membrane and the inner and outer segment junctions, with disorganized material in the vitelliform space. Fundus autofluorescence showed hypoautofluorescence surrounded by a relatively hyperautofluorescent ring, bilaterally. Similar clinical and morphological findings were detected in a 27-year-old male. Conclusions. Solar retinopathy has a subtle presentation and patients often deny sun-gazing. SD-OCT and fundus autofluorescence are noninvasive and useful tools for its diagnosis.

  13. Retinopathy of Prematurity: Clinical Features, Classification, Natural History, Management and Outcome.

    Science.gov (United States)

    Shah, Parag K; Prabhu, Vishma; Ranjan, Ratnesh; Narendran, Venkatapathy; Kalpana, Narendran

    2016-11-07

    Retinopathy of prematurity is an avoidable cause of childhood blindness. Proper understanding of the classification and treatment methods is a must in tackling this disease. Literature search with PubMed was conducted covering the period 1940-2015 with regards to retinopathy of prematurity, retrolental fibroplasia, its natural history, classification and treatment. The clinical features, screening and staging of retinopathy of prematurity according to International classification of retinopathy of prematurity (ICROP) has been included with illustrations. The standard current treatment indications, modalities and outcomes from landmark randomized controlled trials on retinopathy of prematurity have been mentioned. This review would help pediatricians to update their current knowledge on classification and treatment of retinopathy of prematurity. Screening for retinopathy of prematurity, in India, should be performed in all preterm neonates who are born <34 weeks gestation and/or <1750 grams birthweight; as well as in babies 34-36 weeks gestation or 1750-2000 grams birthweight if they have risk factors for ROP. Screening should start by one month after birth.

  14. Predictors of Diabetic Retinopathy in Patients with Type 2 Diabetes ...

    African Journals Online (AJOL)

    Predictors of Diabetic Retinopathy in Patients with Type 2 Diabetes Who Have Normoalbuminuria. R Karoli, J Fatima, V Shukla, P Garg, A Ali. Abstract. Background: Microalbuminuria is an independent predictor of retinopathy, so absence of microalbuminuria may tend clinician not to screen for diabetic retinopathy (DR).

  15. Hyperbaric oxygen in the treatment of radiation-induced optic neuropathy

    International Nuclear Information System (INIS)

    Guy, J.; Schatz, N.J.

    1986-01-01

    Four patients with radiation-induced optic neuropathies were treated with hyperbaric oxygen. They had received radiation therapy for treatment of pituitary tumors, reticulum cell sarcoma, and meningioma. Two presented with amaurosis fugax before the onset of unilateral visual loss and began hyperbaria within 72 hours after development of unilateral optic neuropathy. Both had return of visual function to baseline levels. The others initiated treatment two to six weeks after visual loss occurred in the second eye and had no significant improvement of vision. Treatment consisted of daily administration of 100% oxygen under 2.8 atmospheres of pressure for 14-28 days. There were no medical complications of hyperbaria. While hyperbaric oxygen is effective in the treatment of radiation-induced optic neuropathy, it must be instituted within several days of deterioration in vision for restoration of baseline function

  16. Retinopathy of prematurity: an epidemic in the making.

    Science.gov (United States)

    Quinn, Graham E; Gilbert, Clare; Darlow, Brian A; Zin, Andrea

    2010-10-01

    To explore the etiology, incidence and methods to prevent and treat severe retinopathy of prematurity (ROP), which is rapidly becoming a threat to the vision of babies in areas of the world where increasing numbers of premature babies are surviving. The data used in this review were mainly from Medline and PubMed published in English. The search term was "retinopathy of prematurity and premature birth". We discuss the historical perspectives, prevalence and incidence, classification and treatment methods of ROP in premature babies. Peripheral retinal ablation for eyes with severe ROP can help prevent progression to blindness and several large clinical trials have shown the effectiveness of this treatment in high risk eyes. As a greater proportion of VLBW and ELBW babies survive, the population of babies at risk increases. In various regions of the world, different identification criteria are used to determine which babies are at risk of blindness in order to provide timely diagnostic examinations and treatment as needed. Methods for preventing ROP include better ante-natal and obstetric care leading to a reduction in the rate of prematurity, the use of ante-natal corticosteroids, and better neonatal care practices. Recent developments have indicated that management of oxygen supplementation is important for the prevention of severe ROP; however, there is not yet known what oxygen saturation target should be adopted. Sepsis increases severe ROP in very preterm infants. Genetic associations and a telemedicine approach may be explored to detect ROP. Treatment of anti-VEGF therapy are potentially useful in eyes with severe ROP, but long term effects are not yet known and such treatment should be used with great caution. ROP is a potentially binding disease for premature babies which is becoming more prevalent with the development improving neonatal services in many countries in recent years. High priority should be placed on developing approaches to prevent ROP

  17. Epidemiology of diabetic retinopathy and maculopathy in Africa: a systematic review

    Science.gov (United States)

    Burgess, P I; MacCormick, I J C; Harding, S P; Bastawrous, A; Beare, N A V; Garner, P

    2013-01-01

    Abstract Aim To summarize findings from studies reporting the prevalence and incidence of diabetic retinopathy and diabetic maculopathy in African countries in light of the rising prevalence of diabetes mellitus. Methods Using a predefined search strategy, we systematically searched MEDLINE, EMBASE, Science Citation index and Conference Proceedings Citation index, African Index Medicus and the grey literature database ‘OpenSIGLE’ for studies published between January 1990 and February 2011. Included studies reported prevalence or incidence of diabetic retinopathy or diabetic maculopathy of subjects with diabetes resident in African countries. Results Sixty-two studies from 21 countries were included: three population-based surveys; two cohort studies; five case–control studies; 32 diabetes clinic-based, nine eye clinic-based and 11 other hospital-based surveys. Included studies varied considerably in terms of patient selection, method of assessing the eye and retinopathy classification. In population-based studies, the reported prevalence range in patients with diabetes for diabetic retinopathy was 30.2 to 31.6%, proliferative diabetic retinopathy 0.9 to 1.3%, and any maculopathy 1.2 to 4.5%. In diabetes clinic-based surveys, the reported prevalence range for diabetic retinopathy was 7.0 to 62.4%, proliferative diabetic retinopathy 0 to 6.9%, and any maculopathy 1.2 to 31.1%. No obvious association between prevalence and income level of the country was detected. Conclusions Large, community-based cross-sectional and cohort studies are needed to investigate rates and determinants of prevalence of diabetic retinopathy, incidence and progression in Africa. Consensus is needed on the most appropriate methods of identification and classification of retinopathy for research and clinical practice. Estimates of prevalence of diabetic retinopathy, proliferative diabetic retinopathy and maculopathy are comparable with recent European and American studies. PMID:22817387

  18. Photocoagulation treatment of radiation retinopathy

    International Nuclear Information System (INIS)

    Kinyoun, J.L.; Chittum, M.E.; Wells, C.G.

    1988-01-01

    We studied the visual and anatomic effects of focal photocoagulation for clinically significant radiation macular edema in five eyes of four patients and panretinal photocoagulation for proliferative radiation retinopathy in six eyes of three patients. Focal and limited scatter photocoagulation was successful in preventing further vision loss in all five eyes treated for macular edema. Three eyes treated with panretinal photocoagulation had regression of neovascularization. The other three eyes treated for proliferative retinopathy subsequently had dense vitreous hemorrhages that required vitrectomy for restoration of useful vision

  19. Gastric injury induced by hemorrhage, local ischemia, and oxygen radical generation

    International Nuclear Information System (INIS)

    Wadhwa, S.S.; Perry, M.A.

    1987-01-01

    Gastric mucosal injury caused by local intra-arterial generation of oxygen-derived free radicals was compared with gastric injury caused by 30 min of hemorrhage-induced ischemia or local ischemia. The index of injury was the loss of 51 Cr-labeled red cells across the gastric mucosa. Generation of oxygen radicals in the celiac artery caused a rapid increase in mucosal blood loss during the period of radical generation, and this loss was maintained after radical production ceased. Local ischemia produced similar mucosal injury; however, this occurred after reperfusion of the stomach and not during the ischemic episode. Hemorrhage-induced ischemia produced a threefold greater mucosal blood loss than local ischemia. The results of this study indicate that (1) oxygen radicals generated enzymatically in the blood supply to the stomach cause mucosal bleeding of similar magnitude to that observed after local ischemia and (2) that gastric ischemia induced by systemic hypotension produces more severe gastric injury than the same level of local hypotension

  20. Periodontitis is associated with diabetic retinopathy in non-obese adults.

    Science.gov (United States)

    Song, Su Jeong; Lee, Seong-Su; Han, Kyungdo; Park, Jun-Beom

    2017-04-01

    Patients with diabetes retinopathy appear to show increased susceptibility to periodontal disease. This study was performed to assess the relationship between periodontitis and the prevalence of diabetic retinopathy in a large probability sample of the Korean population. A subgroup analysis was performed using body mass index diabetic retinopathy in relation to demographic variables and anthropometric characteristics of the participants is presented as means with their standard errors. The presence of periodontitis and presence of retinopathy categorized by body mass index (diabetic retinopathy after adjustment with variables, including age, sex, smoking, drinking, exercise, hypertension, metabolic syndrome, HbA1c, and duration of diabetes mellitus. There was a statistically significant increase in the prevalence of periodontitis in individuals who had proliferative diabetic retinopathy. The odds ratios [95% confidence intervals] of prevalence of diabetic retinopathy were 1.193 [0.757-1.881] for the whole population after adjustments with confounding factors. Subgroup analysis after adjustments with confounding factors showed that the odds ratios [95% confidence intervals] of prevalence were 2.206 [1.114-4.366] and 0.588 [0.326-1.061] among participants with body mass index diabetic retinopathy was positively associated with the presence of periodontitis in non-obese diabetic Korean adults after adjustment with confounding variables. Our findings suggest that when a periodontist finds the presence of periodontitis in non-obese diabetic patients, timely evaluation of the patient's ophthalmic evaluation should be 44 recommended.

  1. Radiation retinopathy

    International Nuclear Information System (INIS)

    Parker, R.G.; Withers, H.R.

    1988-01-01

    A letter to the editor discusses the effectiveness and risk of radiation treatment of Grave's ophthalmopathy. The authors are unable to document a single instance in which retinopathy can be attributed to therapy with a total dose of 2000 cGy when delivered in daily increments of 180 to 200 cGy

  2. xidative Stress and Retinopathy of Prematurity

    OpenAIRE

    Ümeyye Taka Aydın; Hatip Aydın; Osman Çekiç

    2014-01-01

    Oxidative stress plays an important role in the etiology of retinopathy of prematurity. Insufficient antioxidant system and increased oxidative stress in premature infants lead to the development of the disease. Understanding the mechanism of oxidative stress and antioxidant system and the related signaling pathways contribute to the development of novel options for diagnosis and treatment of retinopathy of prematurity. The current review aimed to evaluate the relationship between ox...

  3. CD40 in Retinal Müller Cells Induces P2X7-Dependent Cytokine Expression in Macrophages/Microglia in Diabetic Mice and Development of Early Experimental Diabetic Retinopathy.

    Science.gov (United States)

    Portillo, Jose-Andres C; Lopez Corcino, Yalitza; Miao, Yanling; Tang, Jie; Sheibani, Nader; Kern, Timothy S; Dubyak, George R; Subauste, Carlos S

    2017-02-01

    Müller cells and macrophages/microglia are likely important for the development of diabetic retinopathy; however, the interplay between these cells in this disease is not well understood. An inflammatory process is linked to the onset of experimental diabetic retinopathy. CD40 deficiency impairs this process and prevents diabetic retinopathy. Using mice with CD40 expression restricted to Müller cells, we identified a mechanism by which Müller cells trigger proinflammatory cytokine expression in myeloid cells. During diabetes, mice with CD40 expressed in Müller cells upregulated retinal tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), intracellular adhesion molecule 1 (ICAM-1), and nitric oxide synthase (NOS2), developed leukostasis and capillary degeneration. However, CD40 did not cause TNF-α or IL-1β secretion in Müller cells. TNF-α was not detected in Müller cells from diabetic mice with CD40 + Müller cells. Rather, TNF-α was upregulated in macrophages/microglia. CD40 ligation in Müller cells triggered phospholipase C-dependent ATP release that caused P2X 7 -dependent production of TNF-α and IL-1β by macrophages. P2X 7 -/- mice and mice treated with a P2X 7 inhibitor were protected from diabetes-induced TNF-α, IL-1β, ICAM-1, and NOS2 upregulation. Our studies indicate that CD40 in Müller cells is sufficient to upregulate retinal inflammatory markers and appears to promote experimental diabetic retinopathy and that Müller cells orchestrate inflammatory responses in myeloid cells through a CD40-ATP-P2X 7 pathway. © 2017 by the American Diabetes Association.

  4. ADVANCES IN UNDERSTANDING AND MANAGEMENT OF RETINOPATHY OF PREMATURITY

    Science.gov (United States)

    Hartnett, Mary Elizabeth

    2016-01-01

    The understanding, diagnosis and treatment of retinopathy of prematurity (ROP) have changed in the last seventy years since the original description of retrolental fibroplasia associated with high oxygenation. It is now recognized that ROP differs in appearance world-wide and as ever smaller and younger premature infants survive. New methods are being evaluated to image the retina, diagnose severe ROP, and determine windows of time for treatment to save eyes and improve visual and neural outcomes. New treatments to promote physiologic retinal vascular development, vascular repair, and inhibit vasoproliferation by regulating proteins involved in vascular endothelial growth factor, insulin-like growth factor, or erythropoietin signaling. Reducing excessive oxidative/nitrosative stress and understanding progenitor cells and neurovascular and glial vascular interactions are being studied. PMID:28012875

  5. Posterior microphthalmos pigmentary retinopathy syndrome.

    Science.gov (United States)

    Pehere, Niranjan; Jalali, Subhadra; Deshmukh, Himanshu; Kannabiran, Chitra

    2011-04-01

    Posterior Microphthalmos Pigmentary Retinopathy Syndrome (PMPRS). Posterior microphthalmos (PM) is a relatively infrequent type of microphthalmos where posterior segment is predominantly affected with normal anterior segment measurements. Herein, we report two siblings with posterior microphthalmos retinopathy syndrome with postulated autosomal recessive mode of inheritance. A 13-year-old child had PM and retinitis pigmentosa (RP) and his 7-year-old sister had PM, RP, and foveoschisis. The genetics of this syndrome and variable phenotype is discussed. Importance of being aware of posterior microphthalmos and its posterior segment associations is highlighted.

  6. Retinal vessel caliber and myopic retinopathy: the blue mountains eye study.

    Science.gov (United States)

    Li, Haitao; Mitchell, Paul; Rochtchina, Elena; Burlutsky, George; Wong, Tien Y; Wang, Jie Jin

    2011-12-01

    To evaluate changes in the retinal vasculature in eyes with myopic retinopathy. Population-based, cross-sectional study. Emmetropic and myopic participants from the Blue Mountains Eye Study baseline survey were included in this study. Myopia was defined as a refractive error of less than -1.00 diopter. Myopic retinopathy was defined if either staphyloma, lacquer crack, Fuchs' spot or chorioretinal atrophy were present in myopic eyes. Retinal vascular caliber was measured from fundus photographs using standardized methods. The association of retinal vascular caliber with myopic retinopathy was assessed using generalized estimating equation models. A total of 2598 eyes of 1409 subjects were selected from 3654 baseline participants, with 2076 emmetropic eyes (normal controls), 486 myopic eyes without myopic retinopathy (myopic controls) and 36 myopic eyes with myopic retinopathy (cases). After adjusting for age, gender, height, body mass index and blood pressure, eyes with myopic retinopathy had significantly narrower mean arteriolar (166.6μm) and venular caliber (213.3μm), compared to normal (188.1μm and 226.9μm, respectively) or myopic control eyes (190.4μm and 227.0μm, respectively) (all P retinopathy and the two control groups remained significant after additional adjustment for refraction (all P retinopathy is associated with attenuation of retinal vessels.

  7. Aggressive posterior retinopathy of prematurity in two of the triplets: a case report.

    Science.gov (United States)

    Wang, Dan; Zhang, Bo; Dong, Yu; Song, E

    2015-02-01

    Aggressive posterior retinopathy of prematurity is identified as a rare, rapidly progressing and severe form of retinopathy of prematurity (ROP). Here, we report the diagnosis and treatment of aggressive posterior retinopathy of prematurity (APROP) in two of the triplets born at low birth weight and small gestational age. A case concerning two triplets who were born at 31 weeks' gestational age with low birth weight and reached bilateral threshold APROP was reported. The ROP of triplets A and B had the characteristic features of aggressive diseases, which were posterior location, prominence of plus disease and rapid progression. Low birth weight and small gestational age, multiple pregnancies, pregnancy-induced hypertension and older age of the mother might account for the presentations of APROP. These cases demonstrate the importance of early screening and diagnosis in APROP infants. Prompt and adequate laser photocoagulation with a large number of high-intensity closely performed spots and early retreatment could be effective and safe for preventing the progression of APROP with plus disease in zone 1 or 2 in premature triplets. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  8. Extracellular matrix metalloproteinase inducer (EMMPRIN) is a potential biomarker of angiogenesis in proliferative diabetic retinopathy.

    Science.gov (United States)

    Abu El-Asrar, Ahmed M; Ahmad, Ajmal; Alam, Kaiser; Siddiquei, Mohammad Mairaj; Mohammad, Ghulam; Hertogh, Gert De; Mousa, Ahmed; Opdenakker, Ghislain

    2017-11-01

    Extracellular matrix metalloproteinase inducer (EMMPRIN) promotes angiogenesis through matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF) production. We investigated the expression levels of EMMPRIN and correlated these levels with VEGF, MMP-1 and MMP-9 in proliferative diabetic retinopathy (PDR). In addition, we examined the expression of EMMPRIN in the retinas of diabetic rats and the effect of EMMPRIN on the induction of angiogenesis regulatory factors in human retinal microvascular endothelial cells (HRMECs). Vitreous samples from 40 PDR and 19 non-diabetic patients, epiretinal membranes from 12 patients with PDR, retinas of rats and HRMECs were studied by enzyme-linked immunosorbent assay (ELISA), immunohistochemistry, Western blot analysis, zymography analysis and RT-PCR. We showed a significant increase in the expression of EMMPRIN, VEGF, MMP-1 and MMP-9 in vitreous samples from PDR patients compared with non-diabetic controls (p EMMPRIN and the levels of VEGF (r = 0.38; p = 0.003), MMP-1 (r = 0.36; p = 0.005) and MMP-9 (r = 0.46; p = 0.003). In epiretinal membranes, EMMPRIN was expressed in vascular endothelial cells and stromal cells. Significant increase of EMMPRIN mRNA was detected in rat retinas after induction of diabetes. EMMPRIN induced hypoxia-inducible factor-1α, VEGF and MMP-1 expression in HRMEC. These results suggest that EMMPRIN/MMPs/VEGF pathway is involved in PDR angiogenesis. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  9. The Danish Registry of Diabetic Retinopathy

    DEFF Research Database (Denmark)

    Andersen, Nis; Hjortdal, Jesper Østergaard; Schielke, Katja Christina

    2016-01-01

    . Denmark (5.5 million inhabitants) has ~320,000 diabetes patients with an annual increase of 27,000 newly diagnosed patients. The Danish Registry of Diabetic Retinopathy (DiaBase) collects data on all diabetes patients aged ≥18 years who attend screening for diabetic eye disease in hospital eye departments...... and in private ophthalmological practice. In 2014-2015, DiaBase included data collected from 77,968 diabetes patients. Main variables: The main variables provide data for calculation of performance indicators to monitor the quality of diabetic eye screening and development of diabetic retinopathy. Data...... with respect to age, sex, best corrected visual acuity, screening frequency, grading of diabetic retinopathy and maculopathy at each visit, progression/regression of diabetic eye disease, and prevalence of blindness were obtained. Data analysis from DiaBase’s latest annual report (2014-2015) indicates...

  10. The Danish Registry of Diabetic Retinopathy

    DEFF Research Database (Denmark)

    Andersen, Nis; Hjortdal, Jesper Østergaard; Schielke, Katja Christina

    2016-01-01

    . Denmark (5.5 million inhabitants) has ~320,000 diabetes patients with an annual increase of 27,000 newly diagnosed patients. The Danish Registry of Diabetic Retinopathy (DiaBase) collects data on all diabetes patients aged ≥18 years who attend screening for diabetic eye disease in hospital eye departments...... and in private ophthalmological practice. In 2014-2015, DiaBase included data collected from 77,968 diabetes patients. MAIN VARIABLES: The main variables provide data for calculation of performance indicators to monitor the quality of diabetic eye screening and development of diabetic retinopathy. Data...... with respect to age, sex, best corrected visual acuity, screening frequency, grading of diabetic retinopathy and maculopathy at each visit, progression/regression of diabetic eye disease, and prevalence of blindness were obtained. Data analysis from DiaBase's latest annual report (2014-2015) indicates...

  11. Microvascular retinopathy in subjects without diabetes

    DEFF Research Database (Denmark)

    Munch, Inger Christine; Kessel, Line; Borch-Johnsen, Knut

    2012-01-01

    Purpose:  Retinal vascular lesions such as microaneurysms and haemorrhages, while typical of diabetic retinopathy, are also seen in subjects without diabetes where they are associated with elevated cardiovascular mortality. In theory, these lesions could be a consequence of past hyperglycaemia. We...... examined the prevalence and risk factors for retinopathy, including lens fluorescence, a biomarker of cumulative life-time glycaemia in adults without diabetes. Methods:  Cross-sectional population-based study of 711 subjects without diabetes (WHO 1999 criteria) aged 30-60 years, including oral glucose...... tolerance testing, clinical and laboratory examinations, non-invasive ocular lens fluorometry and seven-field fundus photography. Results:  Retinopathy was present in 8.3% (CI(95) 6.3-10.3%) of subjects. Higher systolic blood pressure (SBP) (p = 0.032), increasing body mass index (BMI) (p = 0.014) and wider...

  12. Next-generation sequencing analysis of gene regulation in the rat model of retinopathy of prematurity.

    Science.gov (United States)

    Griffith, Rachel M; Li, Hu; Zhang, Nan; Favazza, Tara L; Fulton, Anne B; Hansen, Ronald M; Akula, James D

    2013-08-01

    The purpose of this study was to identify the genes, biochemical signaling pathways, and biological themes involved in the pathogenesis of retinopathy of prematurity (ROP). Next-generation sequencing (NGS) was performed on the RNA transcriptome of rats with the Penn et al. (Pediatr Res 36:724-731, 1994) oxygen-induced retinopathy model of ROP at the height of vascular abnormality, postnatal day (P) 19, and normalized to age-matched, room-air-reared littermate controls. Eight custom-developed pathways with potential relevance to known ROP sequelae were evaluated for significant regulation in ROP: The three major Wnt signaling pathways, canonical, planar cell polarity (PCP), and Wnt/Ca(2+); two signaling pathways mediated by the Rho GTPases RhoA and Cdc42, which are, respectively, thought to intersect with canonical and non-canonical Wnt signaling; nitric oxide signaling pathways mediated by two nitric oxide synthase (NOS) enzymes, neuronal (nNOS) and endothelial (eNOS); and the retinoic acid (RA) signaling pathway. Regulation of other biological pathways and themes was detected by gene ontology using the Kyoto Encyclopedia of Genes and Genomes and the NIH's Database for Annotation, Visualization, and Integrated Discovery's GO terms databases. Canonical Wnt signaling was found to be regulated, but the non-canonical PCP and Wnt/Ca(2+) pathways were not. Nitric oxide signaling, as measured by the activation of nNOS and eNOS, was also regulated, as was RA signaling. Biological themes related to protein translation (ribosomes), neural signaling, inflammation and immunity, cell cycle, and cell death were (among others) highly regulated in ROP rats. These several genes and pathways identified by NGS might provide novel targets for intervention in ROP.

  13. Next Generation Sequencing Analysis of Gene Regulation in the Rat Model of Retinopathy of Prematurity

    Science.gov (United States)

    Griffith, Rachel M.; Li, Hu; Zhang, Nan; Favazza, Tara L.; Fulton, Anne B.; Hansen, Ronald M.; Akula, James D.

    2013-01-01

    Purpose To identify the genes, biochemical signaling pathways and biological themes involved in the pathogenesis of retinopathy of prematurity (ROP). Methods Next-generation sequencing (NGS) was performed on the RNA transcriptome of rats with the Penn et al. (1994) oxygen-induced retinopathy (OIR) model of ROP at the height of vascular abnormality, postnatal day (P) 19, and normalized to age-matched, room-air-reared littermate controls. Eight custom developed pathways with potential relevance to known ROP sequelae were evaluated for significant regulation in ROP: The three major Wnt signaling pathways, canonical, planar cell polarity (PCP), and Wnt/Ca2+, two signaling pathways mediated by the Rho GTPases RhoA and Cdc42, which are respectively thought to intersect with canonical and noncanonical Wnt signaling, nitric oxide signaling pathways mediated by two nitrox oxide synthase (NOS) enzymes, neuronal (nNOS) and endothelial (eNOS), and the retinoic acid (RA) signaling pathway. Regulation of other biological pathways and themes were detected by gene ontology using the Kyoto Encyclopedia of Genes and Genomes (KEGG) and the NIH's Database for Annotation, Visualization and Integrated Discovery (DAVID)'s GO terms databases. Results Canonical Wnt signaling was found to be regulated, but the non-canonical PCP and Wnt/Ca2+ pathways were not. Nitric oxide (NO) signaling, as measured by the activation of nNOS eNOS, was also regulated, as was RA signaling. Biological themes related to protein translation (ribosomes), neural signaling, inflammation and immunity, cell cycle and cell death, were (among others) highly regulated in ROP rats. Conclusions These several genes and pathways identified by NGS might provide novel targets for intervention in ROP. PMID:23775346

  14. Targeting Neovascularization in Ischemic Retinopathy: Recent Advances

    Science.gov (United States)

    Al-Shabrawey, Mohamed; Elsherbiny, Mohamed; Nussbaum, Julian; Othman, Amira; Megyerdi, Sylvia; Tawfik, Amany

    2014-01-01

    Pathological retinal neovascularization (RNV) is a common micro-vascular complication in several retinal diseases including retinopathy of prematurity, diabetic retinopathy, age-related macular degeneration and central vein occlusion. The current therapeutic modalities of RNV are invasive and although they may slow or halt the progression of the disease they are unlikely to restore normal acuity. Therefore, there is an urgent need to develop treatment modalities, which are less invasive and therefore associated with fewer procedural complications and systemic side effects. This review article summarizes our understanding of the pathophysiology and current treatment of RNV in ischemic retinopathies; lists potential therapeutic targets; and provides a framework for the development of future treatment modalities. PMID:25598837

  15. Quantitative assessment of early diabetic retinopathy using fractal analysis.

    Science.gov (United States)

    Cheung, Ning; Donaghue, Kim C; Liew, Gerald; Rogers, Sophie L; Wang, Jie Jin; Lim, Shueh-Wen; Jenkins, Alicia J; Hsu, Wynne; Li Lee, Mong; Wong, Tien Y

    2009-01-01

    Fractal analysis can quantify the geometric complexity of the retinal vascular branching pattern and may therefore offer a new method to quantify early diabetic microvascular damage. In this study, we examined the relationship between retinal fractal dimension and retinopathy in young individuals with type 1 diabetes. We conducted a cross-sectional study of 729 patients with type 1 diabetes (aged 12-20 years) who had seven-field stereoscopic retinal photographs taken of both eyes. From these photographs, retinopathy was graded according to the modified Airlie House classification, and fractal dimension was quantified using a computer-based program following a standardized protocol. In this study, 137 patients (18.8%) had diabetic retinopathy signs; of these, 105 had mild retinopathy. Median (interquartile range) retinal fractal dimension was 1.46214 (1.45023-1.47217). After adjustment for age, sex, diabetes duration, A1C, blood pressure, and total cholesterol, increasing retinal vascular fractal dimension was significantly associated with increasing odds of retinopathy (odds ratio 3.92 [95% CI 2.02-7.61] for fourth versus first quartile of fractal dimension). In multivariate analysis, each 0.01 increase in retinal vascular fractal dimension was associated with a nearly 40% increased odds of retinopathy (1.37 [1.21-1.56]). This association remained after additional adjustment for retinal vascular caliber. Greater retinal fractal dimension, representing increased geometric complexity of the retinal vasculature, is independently associated with early diabetic retinopathy signs in type 1 diabetes. Fractal analysis of fundus photographs may allow quantitative measurement of early diabetic microvascular damage.

  16. RETINOPATHY, GLUCOSE, AND INSULIN IN AN ELDERLY POPULATION - THE ROTTERDAM STUDY

    NARCIS (Netherlands)

    STOLK, RP; VINGERLING, [No Value; DEJONG, PTVM; DIELEMANS, Hubertus J.A.; HOFMAN, A; LAMBERTS, SWJ; POLS, HAP; GROBBEE, DE

    We studied the association between retinopathy and glucose metabolism in a population-based study of elderly men and women, Glucose metabolism was assessed by serum fructosamine and a nonfasting oral glucose tolerance test, and retinopathy was evaluated by fundus photography, Retinopathy was present

  17. Risk of Radiation Retinopathy in Patients With Orbital and Ocular Lymphoma

    International Nuclear Information System (INIS)

    Kaushik, Megha; Pulido, Jose S.; Schild, Steven E.; Stafford, Scott

    2012-01-01

    Purpose: Radiation retinopathy is a potential long-term complication of radiation therapy to the orbit. The risk of developing this adverse effect is dose dependent; however, the threshold is unclear. The aim of this study was to identify the risk of developing radiation retinopathy at increasing radiation doses. Methods and Materials: A 40-year retrospective review was performed of patients who received external beam radiation therapy for ocular/orbital non-Hodgkin lymphoma (NHL). Results: Sixty-seven patients who had at least one ophthalmic follow-up examination were included in this study. Most patients (52%) were diagnosed with NHL involving the orbit. Patients received external beam radiation therapy at doses between 1886 and 5400 cGy (mean, 3033 ± 782 cGy). Radiation retinopathy developed in 12% of patients, and the median time to diagnosis was 27 months (range, 15-241months). The mean prescribed radiation dose in patients with retinopathy was 3309 ± 585 cGy, and the estimated retinal dose (derived by reviewing the dosimetry) was 3087 ± 1030 cGy. The incidence of retinopathy increased with dose. The average prescribed daily fractionated dose was higher in patients who developed retinopathy than in patients who did not (mean, 202 cGy vs 180 cGy, respectively; P = .04). More patients with radiation retinopathy had comorbid diabetes mellitus type 2 than patients without retinopathy (P = .015). In our study, the mean visual acuity of the eyes that received radiation was worse than that of the eyes that did not (P = .027). Other postradiotherapy ocular findings included keratitis (6%), dry eyes (39%), and cataract (33%). Conclusions: Radiation retinopathy, a known complication of radiotherapy for orbital tumors, relates to vascular comorbidities and dose. Higher total doses and larger daily fractions (>180 cGy) appear to be related to higher rates of retinopathy. Future larger studies are required to identify a statistically significant threshold for the

  18. Risk of Radiation Retinopathy in Patients With Orbital and Ocular Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, Megha; Pulido, Jose S. [Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota (United States); Schild, Steven E. [Division of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States); Stafford, Scott, E-mail: stafford.scott@mayo.edu [Division of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2012-12-01

    Purpose: Radiation retinopathy is a potential long-term complication of radiation therapy to the orbit. The risk of developing this adverse effect is dose dependent; however, the threshold is unclear. The aim of this study was to identify the risk of developing radiation retinopathy at increasing radiation doses. Methods and Materials: A 40-year retrospective review was performed of patients who received external beam radiation therapy for ocular/orbital non-Hodgkin lymphoma (NHL). Results: Sixty-seven patients who had at least one ophthalmic follow-up examination were included in this study. Most patients (52%) were diagnosed with NHL involving the orbit. Patients received external beam radiation therapy at doses between 1886 and 5400 cGy (mean, 3033 {+-} 782 cGy). Radiation retinopathy developed in 12% of patients, and the median time to diagnosis was 27 months (range, 15-241months). The mean prescribed radiation dose in patients with retinopathy was 3309 {+-} 585 cGy, and the estimated retinal dose (derived by reviewing the dosimetry) was 3087 {+-} 1030 cGy. The incidence of retinopathy increased with dose. The average prescribed daily fractionated dose was higher in patients who developed retinopathy than in patients who did not (mean, 202 cGy vs 180 cGy, respectively; P = .04). More patients with radiation retinopathy had comorbid diabetes mellitus type 2 than patients without retinopathy (P = .015). In our study, the mean visual acuity of the eyes that received radiation was worse than that of the eyes that did not (P = .027). Other postradiotherapy ocular findings included keratitis (6%), dry eyes (39%), and cataract (33%). Conclusions: Radiation retinopathy, a known complication of radiotherapy for orbital tumors, relates to vascular comorbidities and dose. Higher total doses and larger daily fractions (>180 cGy) appear to be related to higher rates of retinopathy. Future larger studies are required to identify a statistically significant threshold for the

  19. Two cases of radiation retinopathy

    International Nuclear Information System (INIS)

    Shoda, Miho; Yuzawa, Mitsuko; Matsui, Mizuo; Kaneko, Akihiro.

    1992-01-01

    Radiation retinopathy is characterized by retinal micovascular abnormalities after radiation therapy of the eye and its surrounding structures. The authors performed focal laser photocoagulation in two cases of radiation retinopathy. Case 1 was a 16 year old woman with radiation retinopathy who had been treated for retioblastoma in her right eye using cobalt 60-applicator 16 years prior to the first visit. Her corrected visual acuity of the right eye was 0.4. Ophthalmoscopy revealed large macular deposits, soft exudates, and retinal hemorrhage. Fluorescein angiography showed hyperpermeability of capillaries in the vicinity of the lower temporal retinal vessels. The visual acuity improved to 1.2 after the photocoagulation. Case 2 was a 16 year old man who had received 50 gray of external beam for a primary rhabdo-myosarcoma in the temporal region. Retinal avascular areas in the posterior pole of his both eyes were observed and the area showed increased retinal vessel permeability in the right eye was photocoagulated. The visual acuity in his right eye increased from 0.08 to 1.0 following the treatment. (author)

  20. The potential association between obstructive sleep apnea and diabetic retinopathy in severe obesity-the role of hypoxemia.

    Directory of Open Access Journals (Sweden)

    Dev Banerjee

    Full Text Available Obstructive sleep apnea (OSA is common in obese patients with type 2 diabetes mellitus (DM and may contribute to diabetic microvascular complications.To investigate the association between OSA, hypoxemia during sleep, and diabetic retinal complications in severe obesity. This was a prospective observational study of 93 obese patients mean (SD age: 52(10 years; mean (SD body mass index (BMI: 47.3(8.3 kg/m(2 with DM undergoing retinal screening and respiratory monitoring during sleep. OSA was defined as apnea-hypopnea index (AHI of ≥15 events/hour, resulting in two groups (OSA+ vs. OSA-.Forty-six patients were OSA+: median (95% CI AHI = 37(23-74/hour and 47 were OSA-ve (AHI = 7(4-11/hour. Both groups were similar for ethnicity, BMI, cardiovascular co-morbidities, diabetes duration, HbA1c, and insulin treatment (p>0.05. The OSA+ group was significantly more hypoxemic. There was no significant difference between OSA+ and OSA- groups for the presence of retinopathy (39% vs. 38%. More OSA+ subjects had maculopathy (22% vs. 13%, but this did not reach statistical significance. Logistic regression analyses showed that AHI was not significantly associated with the presence of retinopathy or maculopathy (p>0.05. Whilst minimum oxygen saturation was not significantly associated with retinopathy, it was an independent predictor for the presence of maculopathy OR = 0.79 (95% CI: 0.65-0.95; p<0.05, after adjustment.The presence of OSA, as determined by AHI, was not associated with diabetic retinal complications. In contrast, severity of hypoxemia during sleep (minimum oxygen saturations may be an important factor. The importance of hypoxia in the development of retinal complications in patients with OSA remains unclear and further studies assessing the pathogenesis of hypoxemia in patients with OSA and diabetic retinal disease are warranted.

  1. The role of retinopathy distribution and other lesion types for the definition of examination intervals during screening for diabetic retinopathy.

    Science.gov (United States)

    Ometto, Giovanni; Erlandsen, Mogens; Hunter, Andrew; Bek, Toke

    2017-06-01

    It has previously been shown that the intervals between screening examinations for diabetic retinopathy can be optimized by including individual risk factors for the development of the disease in the risk assessment. However, in some cases, the risk model calculating the screening interval may recommend a different interval than an experienced clinician. The purpose of this study was to evaluate the influence of factors unrelated to diabetic retinopathy and the distribution of lesions for discrepancies between decisions made by the clinician and the risk model. Therefore, fundus photographs from 90 screening examinations where the recommendations of the clinician and a risk model had been discrepant were evaluated. Forty features were defined to describe the type and location of the lesions, and classification and ranking techniques were used to assess whether the features could predict the discrepancy between the grader and the risk model. Suspicion of tumours, retinal degeneration and vascular diseases other than diabetic retinopathy could explain why the clinician recommended shorter examination intervals than the model. Additionally, the regional distribution of microaneurysms/dot haemorrhages was important for defining a photograph as belonging to the group where both the clinician and the risk model had recommended a short screening interval as opposed to the other decision alternatives. Features unrelated to diabetic retinopathy and the regional distribution of retinal lesions may affect the recommendation of the examination interval during screening for diabetic retinopathy. The development of automated computerized algorithms for extracting information about the type and location of retinal lesions could be expected to further optimize examination intervals during screening for diabetic retinopathy. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Relationship between serum 25-hydroxy vitamin D levels and retinopathy of prematurity.

    Science.gov (United States)

    Kabataş, Emrah Utku; Dinlen, Nurdan Fettah; Zenciroğlu, Ayşegül; Dilli, Dilek; Beken, Serdar; Okumuş, Nurullah

    2017-11-01

    Aim To evaluate the relationship between serum 25-hydroxy vitamin D, 25 (OH) D, levels and retinopathy of prematurity. Methods and Results Serum 25 (OH) D levels were measured in 97 very low birth weight infants, prior to vitamin D supplementation. The development of retinopathy of prematurity and its treatment requirement were evaluated. At follow-up, retinopathy of prematurity developed in 71 (73.2%) infants. Serum 25 (OH) D levels were significantly lower in infants with retinopathy of prematurity than ones without retinopathy of prematurity ( P prematurity development [OR: 1.14, 95% CI (1.02-1.27), P = 0.02]. Conclusion Lower 25 (OH) D levels in the first days of life may be related to retinopathy of prematurity development and treatment requirement in premature infants.

  3. Radiation-induced lipid peroxidation: influence of oxygen concentration and membrane lipid composition

    International Nuclear Information System (INIS)

    Wolters, H.; Tilburg, C.A.M. van; Konings, A.W.T.

    1987-01-01

    Radiation -induced lipid peroxidation phospholipid liposomes was investigated in terms of its dependence on lipid composition and oxygen concentration. Non-peroxidizable lipid incorporated in the liposomes reduced the rate of peroxidation of the peroxidizable phospholipid acyl chains, possibly by restricting the length of chain reactions. The latter effect is believed to be caused by interference of the non-peroxidizable lipids in the bilayer. At low oxygen concentration lipid peroxidation was reduced. The cause of this limited peroxidation may be a reduced number of radical initiation reactions possibly involving oxygen-derived superoxide radicals. Killing of proliferating mammalian cells, irradiated at oxygen concentrations ranging from 0 to 100%, appeared to be independent of the concentration of peroxidizable phospholipids in the cell membranes. This indicates that lipid peroxidation is not the determining process in radiation-induced reproductive cell death. (author)

  4. CTRP3 is a novel biomarker for diabetic retinopathy and inhibits HGHL-induced VCAM-1 expression in an AMPK-dependent manner.

    Directory of Open Access Journals (Sweden)

    Zheyi Yan

    Full Text Available Diabetic retinopathy (DR is a severe complication of chronic diabetes. The C1q/TNF-related protein family (CTRPs has been demonstrated to exert protective effects against obesity and atherosclerosis in animal studies. Heretofore, the association between circulating CTRPs and DR patients has been unexplored. In the current study, we attempt to define this association, as well as the effect of CTRPs upon DR pathophysiology.The present investigation is a case control study that enrolled control subjects and type 2 diabetes mellitus (T2DM patients diagnosed with DR. Serum CTRPs and sVACM-1 were determined by ELISA.Serum CTRP3 and CTRP5 levels were markedly decreased in patients with T2DM compared to controls (p<0.05 and inversely associated with T2DM. Furthermore, mutivariate regression and ROC analysis revealed CTRP3 deficiency, not CTRP5, was associated with proliferative diabetic retinopathy (PDR. Spearman's rank correlation assay demonstrated an inverse association between CTRP3 and sVCAM-1. Finally, exogenous CTRP3 administration attenuated high glucose high lipid (HGHL-induced VCAM-1 production in an AMPK-dependent manner in cultured human retinal microvascular endothelial cells (HRMECs.CTRP3 may serve as a novel biomarker for DR severity. CTRP3 may represent a future novel therapeutic against DR, a common ocular complication of diabetes.

  5. The role of renin angiotensin system in retinal inflammation

    OpenAIRE

    Zhu, Tong

    2017-01-01

    Purpose: Retinopathy of prematurity (ROP) is the main cause of vision loss and blindness in children, and is replicated and intensively studied in rodent models of oxygen-induced retinopathy (OIR). One signature feature of ROP is retinal neovascularization, which is also present in patients with proliferative diabetic retinopathy (PDR). Inflammation is another feature in ROP and PDR. In both diseases, the renin angiotensin system (RAS) is dysregulated, and blockade of RAS via angiotensin II (...

  6. A Review on Recent Developments for Detection of Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Javeria Amin

    2016-01-01

    Full Text Available Diabetic retinopathy is caused by the retinal micro vasculature which may be formed as a result of diabetes mellitus. Blindness may appear as a result of unchecked and severe cases of diabetic retinopathy. Manual inspection of fundus images to check morphological changes in microaneurysms, exudates, blood vessels, hemorrhages, and macula is a very time-consuming and tedious work. It can be made easily with the help of computer-aided system and intervariability for the observer. In this paper, several techniques for detecting microaneurysms, hemorrhages, and exudates are discussed for ultimate detection of nonproliferative diabetic retinopathy. Blood vessels detection techniques are also discussed for the diagnosis of proliferative diabetic retinopathy. Furthermore, the paper elaborates a discussion on the experiments accessed by authors for the detection of diabetic retinopathy. This work will be helpful for the researchers and technical persons who want to utilize the ongoing research in this area.

  7. A Review on Recent Developments for Detection of Diabetic Retinopathy.

    Science.gov (United States)

    Amin, Javeria; Sharif, Muhammad; Yasmin, Mussarat

    2016-01-01

    Diabetic retinopathy is caused by the retinal micro vasculature which may be formed as a result of diabetes mellitus. Blindness may appear as a result of unchecked and severe cases of diabetic retinopathy. Manual inspection of fundus images to check morphological changes in microaneurysms, exudates, blood vessels, hemorrhages, and macula is a very time-consuming and tedious work. It can be made easily with the help of computer-aided system and intervariability for the observer. In this paper, several techniques for detecting microaneurysms, hemorrhages, and exudates are discussed for ultimate detection of nonproliferative diabetic retinopathy. Blood vessels detection techniques are also discussed for the diagnosis of proliferative diabetic retinopathy. Furthermore, the paper elaborates a discussion on the experiments accessed by authors for the detection of diabetic retinopathy. This work will be helpful for the researchers and technical persons who want to utilize the ongoing research in this area.

  8. Protective effects of methane-rich saline on diabetic retinopathy via anti-inflammation in a streptozotocin-induced diabetic rat model

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jiangchun; Wang, Ruobing [Department of Ophthalmology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai (China); Ye, Zhouheng; Sun, Xuejun [Department of Navy Aeromedicine, Second Military Medical University, Shanghai (China); Chen, Zeli; Xia, Fangzhou; Sun, Qinglei [Department of Ophthalmology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai (China); Liu, Lin, E-mail: linliu@sh163.net [Department of Ophthalmology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai (China)

    2015-10-16

    As the commonest complication of diabetes mellitus (DM), diabetic retinopathy (DR) is a neuro-vascular disease with chronic inflammatory. Methane could exert potential therapeutic interest in inflammatory pathologies in previous studies. Our study aims to evaluate the protective effects of methane-rich saline on DR and investigate the potential role of related MicroRNA (miRNA) in diabetic rats. Streptozotocin-induced diabetic Sprague–Dawley rats were injected intraperitoneally with methane-rich or normal saline (5 ml/kg) daily for eight weeks. Morphology changes and blood-retinal barrier (BRB) permeability were assessed by hematoxylin eosin staining and Evans blue leakage. Retinal inflammatory cytokines levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL1-β) were evaluated by immunohistochemistry. Retinal protein expressions of glial fibrillary acidic protein (GFAP) and vascular endothelial growth factor (VEGF) were determined by western blotting. Retinal miRNA expressions were examined by miRNA-specific microarray, verified by quantitative RT-PCR and predicted by GO enrichment and KEGG pathway analysis. There was no significant changes in blood glucose level and body weight of diabetic rats with methane-rich or normal saline treatment, but the decreased retinal thickness, retinal ganglial cell loss and BRB breakdown were all significantly suppressed by methane treatment. DM-induced retinal overexpressions of TNF-α, IL-1β, GFAP and VEGF were also significantly ameliorated. Moreover, the methane treatment significantly up-regulated retinal levels of miR-192-5p (related to apoptosis and tyrosine kinase signaling pathway) and miR-335 (related to proliferation, oxidative stress and leukocyte). Methane exerts protective effect on DR via anti-inflammation, which may be related to the regulatory mechanism of miRNAs. - Highlights: • Methane exerts protective effect on diabetic retinopathy via anti-inflammation. • Therapeutic effect of methane is

  9. Protective effects of methane-rich saline on diabetic retinopathy via anti-inflammation in a streptozotocin-induced diabetic rat model

    International Nuclear Information System (INIS)

    Wu, Jiangchun; Wang, Ruobing; Ye, Zhouheng; Sun, Xuejun; Chen, Zeli; Xia, Fangzhou; Sun, Qinglei; Liu, Lin

    2015-01-01

    As the commonest complication of diabetes mellitus (DM), diabetic retinopathy (DR) is a neuro-vascular disease with chronic inflammatory. Methane could exert potential therapeutic interest in inflammatory pathologies in previous studies. Our study aims to evaluate the protective effects of methane-rich saline on DR and investigate the potential role of related MicroRNA (miRNA) in diabetic rats. Streptozotocin-induced diabetic Sprague–Dawley rats were injected intraperitoneally with methane-rich or normal saline (5 ml/kg) daily for eight weeks. Morphology changes and blood-retinal barrier (BRB) permeability were assessed by hematoxylin eosin staining and Evans blue leakage. Retinal inflammatory cytokines levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL1-β) were evaluated by immunohistochemistry. Retinal protein expressions of glial fibrillary acidic protein (GFAP) and vascular endothelial growth factor (VEGF) were determined by western blotting. Retinal miRNA expressions were examined by miRNA-specific microarray, verified by quantitative RT-PCR and predicted by GO enrichment and KEGG pathway analysis. There was no significant changes in blood glucose level and body weight of diabetic rats with methane-rich or normal saline treatment, but the decreased retinal thickness, retinal ganglial cell loss and BRB breakdown were all significantly suppressed by methane treatment. DM-induced retinal overexpressions of TNF-α, IL-1β, GFAP and VEGF were also significantly ameliorated. Moreover, the methane treatment significantly up-regulated retinal levels of miR-192-5p (related to apoptosis and tyrosine kinase signaling pathway) and miR-335 (related to proliferation, oxidative stress and leukocyte). Methane exerts protective effect on DR via anti-inflammation, which may be related to the regulatory mechanism of miRNAs. - Highlights: • Methane exerts protective effect on diabetic retinopathy via anti-inflammation. • Therapeutic effect of methane is

  10. Redox-Triggered Bonding-Induced Emission of Thiol-Functionalized Gold Nanoclusters for Luminescence Turn-On Detection of Molecular Oxygen.

    Science.gov (United States)

    Ao, Hang; Feng, Hui; Zhao, Mengting; Zhao, Meizhi; Chen, Jianrong; Qian, Zhaosheng

    2017-11-22

    Most optical sensors for molecular oxygen were developed based on the quenching effect of the luminescence of oxygen-sensitive probes; however, the signal turn-off mode of these probes is undesirable to quantify and visualize molecular oxygen. Herein, we report a novel luminescence turn-on detection strategy for molecular oxygen via the specific oxygen-triggered bonding-induced emission of thiol-functionalized gold nanoclusters. Thiol-functionalized gold nanoclusters were prepared by a facile one-step synthesis, and as-prepared gold nanoclusters possess significant aggregation-induced emission (AIE) property. It is the first time to discover the oxygen-triggered bonding-induced emission (BIE) behavior of gold nanoclusters, which results in disulfide-linked covalent bonding assemblies with intensely red luminescence. This specific redox-triggered BIE is capable of quantitatively detecting dissolved oxygen in aqueous solution in a light-up manner, and trace amount of dissolved oxygen at ppb level is achieved based on this detection method. A facile and convenient test strip for oxygen detection was also developed to monitor molecular oxygen in a gas matrix. Covalent bonding-induced emission is proven to be a more efficient way to attain high brightness of AIEgens than a physical aggregation-induced emission process, and provides a more convenient and desirable detection method for molecular oxygen than the previous sensors.

  11. Paeoniflorin Suppressed High Glucose-Induced Retinal Microglia MMP-9 Expression and Inflammatory Response via Inhibition of TLR4/NF-κB Pathway Through Upregulation of SOCS3 in Diabetic Retinopathy.

    Science.gov (United States)

    Zhu, Su-Hua; Liu, Bing-Qian; Hao, Mao-Juan; Fan, Yi-Xin; Qian, Cheng; Teng, Peng; Zhou, Xiao-Wei; Hu, Liang; Liu, Wen-Tao; Yuan, Zhi-Lan; Li, Qing-Ping

    2017-10-01

    Diabetic retinopathy (DR) is a serious-threatening complication of diabetes and urgently needed to be treated. Evidence has accumulated indicating that microglia inflammation within the retina plays a critical role in DR. Microglial matrix metalloproteinase 9 (MMP-9) has an important role in the destruction of the integrity of the blood-retinal barrier (BRB) associated with the development of DR. MMP-9 was also considered important for regulating inflammatory responses. Paeoniflorin, a monoterpene glucoside, has a potent immunomodulatory effect on microglia. We hypothesized that paeoniflorin could significantly suppress microglial MMP-9 activation induced by high glucose and further relieve DR. BV2 cells were used to investigate the effects and mechanism of paeoniflorin. The activation of MMP-9 was measured by gelatin zymography. Cell signaling was measured by western blot assay and immunofluorescence assay. High glucose increased the activation of MMP-9 in BV2 cells, which was abolished by HMGB1, TLR4, p38 MAPK, and NF-κB inhibition. Phosphorylation of p38 MAPK induced by high glucose was decreased by TLR4 inhibition in BV2 cells. Paeoniflorin induced suppressor of cytokine signaling 3 (SOCS3) expression and reduced MMP-9 activation in BV2 cells. The effect of paeoniflorin on SOCS3 was abolished by the TLR4 inhibitor. In streptozotocin (STZ)-induced diabetes mice, paeoniflorin induced SOCS3 expression and reduced MMP-9 activation. Paeoniflorin suppressed STZ-induced IBA-1 and IL-1β expression and decreased STZ-induced high blood glucose level. In conclusion, paeoniflorin suppressed high glucose-induced retinal microglia MMP-9 expression and inflammatory response via inhibition of the TLR4/NF-κB pathway through upregulation of SOCS3 in diabetic retinopathy.

  12. Inflammation in Diabetic Retinopathy

    Science.gov (United States)

    Tang, Johnny; Kern, Timothy S.

    2012-01-01

    Diabetes causes a number of metabolic and physiologic abnormalities in the retina, but which of these abnormalities contribute to recognized features of diabetic retinopathy (DR) is less clear. Many of the molecular and physiologic abnormalities that have been found to develop in the retina in diabetes are consistent with inflammation. Moreover, a number of anti-inflammatory therapies have been found to significantly inhibit development of different aspects of DR in animal models. Herein, we review the inflammatory mediators and their relationship to early and late DR, and discuss the potential of anti-inflammatory approaches to inhibit development of different stages of the retinopathy. We focus primarily on information derived from in vivo studies, supplementing with information from in vitro studies were important. PMID:21635964

  13. TPL2 (Therapeutic Targeting Tumor Progression Locus-2)/ATF4 (Activating Transcription Factor-4)/SDF1α (Chemokine Stromal Cell-Derived Factor-α) Axis Suppresses Diabetic Retinopathy.

    Science.gov (United States)

    Lai, De-Wei; Lin, Keng-Hung; Sheu, Wayne Huey-Herng; Lee, Maw-Rong; Chen, Chung-Yu; Lee, Wen-Jane; Hung, Yi-Wen; Shen, Chin-Chang; Chung, Tsung-Ju; Liu, Shing-Hwa; Sheu, Meei-Ling

    2017-09-01

    Diabetic retinopathy is characterized by vasopermeability, vascular leakage, inflammation, blood-retinal barrier breakdown, capillary degeneration, and neovascularization. However, the mechanisms underlying the association between diabetes mellitus and progression retinopathy remain unclear. TPL2 (tumor progression locus 2), a serine-threonine protein kinase, exerts a pathological effect on vascular angiogenesis. This study investigated the role of N ε -(carboxymethyl)lysine, a major advanced glycation end products, and the involved TPL2-related molecular signals in diabetic retinopathy using models of in vitro and in vivo and human samples. Serum N ε -(carboxymethyl)lysine levels and TPL2 kinase activity were significantly increased in clinical patients and experimental animals with diabetic retinopathy. Intravitreal administration of pharmacological blocker or neutralizing antibody inhibited TPL2 and effectively suppressed the pathological characteristics of retinopathy in streptozotocin-induced diabetic animal models. Intravitreal VEGF (vascular endothelial growth factor) neutralization also suppressed the diabetic retinopathy in diabetic animal models. Mechanistic studies in primary human umbilical vein endothelial cells and primary retinal microvascular endothelial cells from streptozotocin-diabetic rats, db/db mice, and samples from patients with diabetic retinopathy revealed a positive parallel correlation between N ε -(carboxymethyl)lysine and the TPL2/chemokine SDF1α (stromal cell-derived factor-α) axis that is dependent on endoplasmic reticulum stress-related molecules, especially ATF4 (activating transcription factor-4). This study demonstrates that inhibiting the N ε -(carboxymethyl)lysine-induced TPL2/ATF4/SDF1α axis can effectively prevent diabetes mellitus-mediated retinal microvascular dysfunction. This signaling axis may include the therapeutic potential for other diseases involving pathological neovascularization or macular edema. © 2017

  14. Recessive Stargardt Disease Phenocopying Hydroxychloroquine Retinopathy

    Science.gov (United States)

    Noupuu, Kalev; Lee, Winston; Zernant, Jana; Greenstein, Vivienne C.; Tsang, Stephen; Allikmets, Rando

    2015-01-01

    Purpose To describe a series of Stargardt disease (STGD1) patients exhibiting a phenotype usually associated with hydroxychloroquine (HCQ) retinopathy on spectral domain-optical coherence tomography (SD-OCT). Methods Observational case series from Columbia University Medical Center involving 8 patients with genetically-confirmed STGD1. Patients selected for the study presented no history of HCQ use. Horizontal macular SD-OCT scans and accompanying 488nm autofluorescence (AF) images, color fundus photographs, and full-field electroretinograms were analyzed. Results All study patients exhibited an abrupt thinning of the parafoveal region or disruption of the outer retinal layers on SD-OCT resembling the transient HCQ retinopathy phenotype. Funduscopy and AF imaging revealed variations of bull’s eye maculopathy (BEM). Five patients exhibited local fleck-like deposits around the lesion. Genetic screening confirmed two disease-causing ABCA4 mutations in 5 patients and one mutation in 3 patients. Conclusions A transient SD- OCT phenotype ascribed to patients with HCQ retinopathy is associated with an early subtype of STGD1. This finding may also present with HCQ retinopathy-like BEM lesions on AF imaging and funduscopy. A phenotypic overlap may not be surprising given certain shared mechanistic disease processes between the two conditions. A thorough work-up, including screening of genes that are causal in retinal dystrophies associated with foveal sparing, may prevent the misdiagnoses of more ambiguous cases. PMID:26311262

  15. Metabolic factors in the development of retinopathy of juvenile-onset type I diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Khosla P

    1994-01-01

    Full Text Available Thirty-five patients of insulin-dependent diabetes mellitus (IDDM were investigated for the effect of various metabolic factors on retinopathy. The severity of retinopathy increased with duration and age of onset of IDDM. Degree of glycaemia (fasting blood sugar, FBS was similar in patients with or without retinopathy. All IDDM patients as a group showed severe carbohydrate intolerance with lower basal and post glucose serum immunoreactive insulin (IRI levels and serum C-peptide radioimmunoreactivity (CPR as compared to controls. The insulin secretory response was similar in no retinopathy, mild retinopathy and severe retinopathy groups. Patients with retinopathy had higher incidence of hyperlipidemia but mean serum levels of cholesterol and triglyceride were similar. This study does not suggest a direct relationship between the various metabolic factors studied and retinopathy due to IDDM

  16. PREVALENCE OF DIABETIC RETINOPATHY IN PATIENTS WITH NEWLY DIAGNOSED TYPE II DIABETES MELLITUS

    Directory of Open Access Journals (Sweden)

    A. Bostak

    2006-11-01

    Full Text Available Diabetic retinopathy is a common complication of type II diabetes mellitus and carries with it the threat of blindness. Accurate information regarding the incidence of diabetic retinopathy and associated risk factors is important in the prevention of its development and of the visual impairment caused by this complication. This study was designed to determine the prevalence of diabetic retinopathy in newly diagnosed patients with type II diabetes mellitus. We have also evaluated the association of diabetic retinopathy with clinical and biochemical variables. In a cross-sectional study, 152 consecutive patients with newly diagnosed type II diabetes mellitus were referred from two outpatient clinics in Tehran for ophthalmologic exam to detect retinopathy. Indirect ophthalmoscopy was performed and data regarding risk factors were extracted from routine medical records. Chi square and Mann Whitney U tests were used to analyze the data. The overall prevalence of diabetic retinopathy was 13.8 %( 21 cases: three cases with microaneurysm only, 10 with mild, 5 with moderate and 2 with severe non proliferative diabetic retinopathy. Only one patient had advanced proliferative retinopathy. The prevalence of diabetic retinopathy was positively associated with age, duration of disease, fasting plasma glucose, HbA1c, and systolic blood pressure. Diabetic retinopathy is common in newly diagnosed type II diabetes mellitus patients. Ophthalmologic consultation is essential at the time of diagnosis for all patients.

  17. Oxygen-induced restructuring with release of gold atoms from Au(111)

    International Nuclear Information System (INIS)

    Min, B.K.; Deng, X.; Schalek, R.; Pinnaduwage, D.; Friend, C.M.

    2005-01-01

    Adsorption of oxygen atoms, achieved via electron-induced dissociation of nitrogen dioxide, induces restructuring of the 'herringbone' to a striped, soliton-wall structure accompanied by release of gold from the 'elbows' in the herringbone structure. The number density of 'elbows' (dislocations corresponding to a change in direction of the reconstruction) decreases as a function of increasing atomic oxygen coverage while the long range order observed in low energy electron diffraction (LEED) changes from (√(3)x22)-rec. to (1x22) in the limit of saturation coverage. Small islands and serrated step edges were formed due to the release of gold atoms from elbow sites of Au(111). The overall structural change of the Au(111) surface may result from the reduction of anisotropy related to the tensile stress relief of the Au(111) surface by oxygen atoms

  18. The Prevalence of Diabetic Retinopathy Among Known Diabetic Population in Nepal.

    Science.gov (United States)

    Mishra, S K; Pant, B P; Subedi, P

    2016-01-01

    Background The worldwide prevalence of diabetic retinopathy (DR) was found to be 34.6%. WHO estimates that DR is responsible for 4.8% of the 37 million cases of blindness throughout the world. In a study undertaken in urban population in Nepal, M.D. Bhattarai found the prevalence of diabetes among people aged 20 years and above to be 14.6% and the prevalence among people aged 40 years and above to be 19%. Studies on DR, to our knowledge, have mostly been hospital based in Nepal. Little information is available about prevalence of DR at the community level in Nepal. Objective To investigate the prevalence of diabetic retinopathy and associated risk factors among known diabetic population of Nepal. Method A descriptive cross sectional study was conducted among individuals aged 30 and more using cluster sampling method. The study sites were Kathmandu metropolitan city and Birgunj sub-metropolitan city. A sample size of 5400 was calculated assuming 5% prevalence rate with 95% confidence level, 5% worst acceptable level and 1.5 cluster sampling design effect. Study participants were interviewed, anthropometric measurements and fundus photograph was taken from participants with diabetes. Fundus photographs were used to grade retinopathy. Result Around 12% of the respondents were diabetic, mean age 55.43±11.86 years, of which slightly more than half were females (50.2%). Among these diabetic respondents 9.9% had some forms of diabetic retinopathy, mean age 54.08±10.34 years, 56.7% were male. When severe grade of retinopathy in any eye was considered as overall grade of retinopathy for the individual, prevalence of Non-proliferative Diabetic Retinopathy, Proliferative Diabetic Retinopathy and complete vision loss was found to be 9.1%, 0.5% and 0.3%. Prevalence of Diabetic Macular Edema was 5.5%. Duration of diabetes, family history of diabetes and blood pressure at the day of survey was found to be associated with having any retinopathy. Conclusion Diabetic retinopathy

  19. Four cases of radiation retinopathy and optic neuropathy

    International Nuclear Information System (INIS)

    Konari, Kenji; Suzuki, Jun-ichi; Nakagawa, Takashi

    1996-01-01

    We observed retinopathy and optic neuropathy in 4 patients after radiation for malignancies in the paranasal sinus or the brain. The dosis ranged from 56 Gy for 14 days to 64 Gy for 32 days. The interval between the termination of radiation and onset of fundus lesions ranged from 1 to 36 months, average 16.6 months. The retinopathy appeared as retinal hemorrhage, soft exudates and vitreous hemorrhage. Neovascular glaucoma developed in one eye. The optic neuropathy appeared as pallor of optic disc, disc edema or optic papillitis. Histological studies of one eye with retinopathy showed thickening of retinal capillary walls and rubeosis iridis with angle closure. (author)

  20. Four cases of radiation retinopathy and optic neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Konari, Kenji; Suzuki, Jun-ichi; Nakagawa, Takashi [Sapporo Medical Coll. (Japan)

    1996-03-01

    We observed retinopathy and optic neuropathy in 4 patients after radiation for malignancies in the paranasal sinus or the brain. The dosis ranged from 56 Gy for 14 days to 64 Gy for 32 days. The interval between the termination of radiation and onset of fundus lesions ranged from 1 to 36 months, average 16.6 months. The retinopathy appeared as retinal hemorrhage, soft exudates and vitreous hemorrhage. Neovascular glaucoma developed in one eye. The optic neuropathy appeared as pallor of optic disc, disc edema or optic papillitis. Histological studies of one eye with retinopathy showed thickening of retinal capillary walls and rubeosis iridis with angle closure. (author).

  1. The metabolic syndrome and severity of diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Chen JJ

    2015-04-01

    Full Text Available John J Chen,1,2,* Lucas J Wendel,1,3,* Emily S Birkholz,1 John G Vallone,4 Anne L Coleman,5,6 Fei Yu,7 Vinit B Mahajan1,3,8 1Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA; 2Mayo Clinic, Rochester, MN, USA; 3Vitreoretinal Service, University of Iowa, Iowa City, IA, USA; 4Department of Pathology, University of Southern California, 5Department of Ophthalmology, 6Department of Epidemiology, School of Public Health, 7Department of Biostatistics, University of California, Los Angeles, CA, USA; 8Omics Laboratory, University of Iowa, Iowa City, IA, USA *These authors contributed equally to this work Background: While metabolic syndrome has been strongly implicated as a risk factor for macrovascular diseases, such as stroke and cardiovascular disease, its relationship with microvascular diseases, including diabetic retinopathy, has been less defined. The purpose of this pilot study was to investigate the association between metabolic syndrome and the presence and severity of diabetic retinopathy.Methods: A retrospective case–control chart review at the University of Iowa ophthalmology and primary care clinics included 100 patients with proliferative diabetic retinopathy (PDR, 100 patients with nonproliferative diabetic retinopathy (NPDR, 100 diabetic patients without diabetic retinopathy, and 100 nondiabetic patients who were randomly selected. Using the International Diabetes Foundation definition, the prevalence of metabolic syndrome and the number of components of metabolic syndrome were compared among these groups.Results: The prevalence of metabolic syndrome in patients with diabetes was 69.3%, which was significantly higher than that in patients without diabetes (27%; P<0.0001 (odds ratio [OR] =6.28; 95% confidence interval [CI]: 3.76–10.49; P=0.0004. However, there was no significant difference in the prevalence of metabolic syndrome between diabetics with and without diabetic retinopathy, with rates

  2. Photobiomodulation Mitigates Diabetes-Induced Retinopathy by Direct and Indirect Mechanisms: Evidence from Intervention Studies in Pigmented Mice.

    Science.gov (United States)

    Saliba, Alexandra; Du, Yunpeng; Liu, Haitao; Patel, Shyam; Roberts, Robin; Berkowitz, Bruce A; Kern, Timothy S

    2015-01-01

    Daily application of far-red light from the onset of diabetes mitigated diabetes-induced abnormalities in retinas of albino rats. Here, we test the hypothesis that photobiomodulation (PBM) is effective in diabetic, pigmented mice, even when delayed until weeks after onset of diabetes. Direct and indirect effects of PBM on the retina also were studied. Diabetes was induced in C57Bl/6J mice using streptozotocin. Some diabetics were exposed to PBM therapy (4 min/day; 670 nm) daily. In one study, mice were diabetic for 4 weeks before initiation of PBM for an additional 10 weeks. Retinal oxidative stress, inflammation, and retinal function were measured. In some mice, heads were covered with a lead shield during PBM to prevent direct illumination of the eye, or animals were treated with an inhibitor of heme oxygenase-1. In a second study, PBM was initiated immediately after onset of diabetes, and administered daily for 2 months. These mice were examined using manganese-enhanced MRI to assess effects of PBM on transretinal calcium channel function in vivo. PBM intervention improved diabetes-induced changes in superoxide generation, leukostasis, expression of ICAM-1, and visual performance. PBM acted in part remotely from the retina because the beneficial effects were achieved even with the head shielded from the light therapy, and because leukocyte-mediated cytotoxicity of retinal endothelial cells was less in diabetics treated with PBM. SnPP+PBM significantly reduced iNOS expression compared to PBM alone, but significantly exacerbated leukostasis. In study 2, PBM largely mitigated diabetes-induced retinal calcium channel dysfunction in all retinal layers. PBM induces retinal protection against abnormalities induced by diabetes in pigmented animals, and even as an intervention. Beneficial effects on the retina likely are mediated by both direct and indirect mechanisms. PBM is a novel non-pharmacologic treatment strategy to inhibit early changes of diabetic retinopathy.

  3. The Adenosinergic System in Diabetic Retinopathy

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    J. Vindeirinho

    2016-01-01

    Full Text Available The neurodegenerative and inflammatory environment that is prevalent in the diabetic eye is a key player in the development and progression of diabetic retinopathy. The adenosinergic system is widely regarded as a significant modulator of neurotransmission and the inflammatory response, through the actions of the four types of adenosine receptors (A1R, A2AR, A2BR, and A3R, and thus could be revealed as a potential player in the events unfolding in the early stages of diabetic retinopathy. Herein, we review the studies that explore the impact of diabetic conditions on the retinal adenosinergic system, as well as the role of the said system in ameliorating or exacerbating those conditions. The experimental results described suggest that this system is heavily affected by diabetic conditions and that the modulation of its components could reveal potential therapeutic targets for the treatment of diabetic retinopathy, particularly in the early stages of the disease.

  4. Efficacy of Intravitreal Bevacizumab for Stage 3+ Retinopathy of Prematurity

    Science.gov (United States)

    Mintz-Hittner, Helen A.; Kennedy, Kathleen A.; Chuang, Alice Z.

    2011-01-01

    BACKGROUND Retinopathy of prematurity is a leading cause of childhood blindness worldwide. Peripheral retinal ablation with conventional (confluent) laser therapy is destructive, causes complications, and does not prevent all vision loss, especially in cases of retinopathy of prematurity affecting zone I of the eye. Case series in which patients were treated with vascular endothelial growth factor inhibitors suggest that these agents may be useful in treating retinopathy of prematurity. METHODS We conducted a prospective, controlled, randomized, stratified, multicenter trial to assess intravitreal bevacizumab monotherapy for zone I or zone II posterior stage 3+ (i.e., stage 3 with plus disease) retinopathy of prematurity. Infants were randomly assigned to receive intravitreal bevacizumab (0.625 mg in 0.025 ml of solution) or conventional laser therapy, bilaterally. The primary ocular outcome was recurrence of retinopathy of prematurity in one or both eyes requiring retreatment before 54 weeks’ postmenstrual age. RESULTS We enrolled 150 infants (total sample of 300 eyes); 143 infants survived to 54 weeks’ postmenstrual age, and the 7 infants who died were not included in the primary-outcome analyses. Retinopathy of prematurity recurred in 4 infants in the bevacizumab group (6 of 140 eyes [4%]) and 19 infants in the laser-therapy group (32 of 146 eyes [22%], P = 0.002). A significant treatment effect was found for zone I retinopathy of prematurity (P = 0.003) but not for zone II disease (P = 0.27). CONCLUSIONS Intravitreal bevacizumab monotherapy, as compared with conventional laser therapy, in infants with stage 3+ retinopathy of prematurity showed a significant benefit for zone I but not zone II disease. Development of peripheral retinal vessels continued after treatment with intravitreal bevacizumab, but conventional laser therapy led to permanent destruction of the peripheral retina. This trial was too small to assess safety. PMID:21323540

  5. Pressure broadening of atomic oxygen two-photon absorption laser induced fluorescence

    NARCIS (Netherlands)

    Marinov, D.; Drag, C.; Blondel, C.; Guaitella, O.; Golda, J.; Klarenaar, B.L.M.; Engeln, R.A.H.; Schulz-von der Gathen, V.; Booth, J.-P.

    2016-01-01

    Atomic oxygen, considered to be a determining reactant in plasma applications at ambient pressure, is routinely detected by two-photon absorption laser induced fluorescence (TALIF). Here, pressure broadening of the (2p 4 3 P 2  →  3p 3 P J=0,1,2) two-photon transition in oxygen atoms was

  6. Assessing Progress in Retinopathy Outcomes in Type 1 Diabetes

    Science.gov (United States)

    LeCaire, Tamara J.; Palta, Mari; Klein, Ronald; Klein, Barbara E.K.; Cruickshanks, Karen J.

    2013-01-01

    OBJECTIVE The Wisconsin Diabetes Registry Study (WDRS) cohort consisted of patients diagnosed with type 1 diabetes in the same geographic region as, but 8–34 years later than the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) cohort, providing a unique opportunity to assess changes in complications. We estimated the current prevalence and severity of diabetic retinopathy at 20 years of diabetes duration, compared these between eras, and evaluated the influence of diabetes management. RESEARCH DESIGN AND METHODS Twenty-year examinations, including fundus photographs, were completed on 305 WDRS subjects during 2007–2011. A subgroup of the WESDR cohort participated in one of four study visits during 1980–1996, at similar diabetes duration (n = 583). Adjusted ordinal logistic regression with three retinopathy severity categories was used to estimate odds ratios (ORs) of more severe retinopathy with diagnosis during an earlier era. RESULTS Mean hemoglobin A1c (HbA1c) was lower in WDRS than in WESDR (8.0% vs. 9.3% [P < 0.001], and 93.4% vs. 21.3% [P < 0.001]) used ≥3 daily insulin injections or an insulin pump. In WDRS, 18% had vision-threatening levels of retinopathy vs. 43% in WESDR. The adjusted OR of more severe retinopathy in the earlier era (OR 3.0 [95% CI 2.2–4.0]) was reduced by including 20-year HbA1c in the model (OR 2.2 [1.6–3.0]). CONCLUSIONS Retinopathy severity at a diabetes duration of 20 years is lower in the more recent era of type 1 diabetes. Updated projections should be used when informing newly diagnosed individuals of prognosis and for health care cost assessments. Current glycemic control explained a limited amount of the difference. PMID:23193204

  7. Prevalence of blindness and diabetic retinopathy in northern Jordan.

    Science.gov (United States)

    Rabiu, Mansur M; Al Bdour, Muawyah D; Abu Ameerh, Mohammed A; Jadoon, Muhammed Z

    2015-01-01

    To estimate the prevalence of blindness, visual impairment, diabetes, and diabetic retinopathy in north Jordan (Irbid) using the rapid assessment of avoidable blindness and diabetic retinopathy methodology. A multistage cluster random sampling technique was used to select participants for this survey. A total of 108 clusters were selected using probability proportional to size method while subjects within the clusters were selected using compact segment method. Survey teams moved from house to house in selected segments examining residents 50 years and older until 35 participants were recruited. All eligible people underwent a standardized examination protocol, which included ophthalmic examination and random blood sugar test using digital glucometers (Accu-Chek) in their homes. Diabetic retinopathy among diabetic patients was assessed through dilated fundus examination. A total of 3638 out of the 3780 eligible participants were examined. Age- and sex-adjusted prevalence of blindness, severe visual impairment, and visual impairment with available correction were 1.33% (95% confidence interval [CI] 0.87-1.73), 1.82% (95% CI 1.35-2.25), and 9.49% (95% CI 8.26-10.74), respectively, all higher in women. Untreated cataract and diabetic retinopathy were the major causes of blindness, accounting for 46.7% and 33.2% of total blindness cases, respectively. Glaucoma was the third major cause, accounting for 8.9% of cases. The prevalence of diabetes mellitus was 28.6% (95% CI 26.9-30.3) among the study population and higher in women. The prevalence of any retinopathy among diabetic patients was 48.4%. Cataract and diabetic retinopathy are the 2 major causes of blindness and visual impairment in northern Jordan. For both conditions, women are primarily affected, suggesting possible limitations to access to services. A diabetic retinopathy screening program needs to proactively create sex-sensitive awareness and provide easily accessible screening services with prompt treatment.

  8. Axial Myopia and its Influence on Diabetic Retinopathy

    International Nuclear Information System (INIS)

    Tayyab, H.; Haider, M. A.; Bukhari, S. A. H.

    2014-01-01

    Objective: To evaluate the correlation between axial myopia and diabetic retinopathy. Study Design: Cross-sectional study. Place and Duration of Study: Eye Department of Postgraduate Medical Institute, Lahore General Hospital, from August 2012 to February 2013. Methodology: A total of 258 participants suffering from type-2 diabetic retinopathy were included. Axial length was measured by two optometrists using contact type ultrasound biometer. Colored retinal photographs, red free retinal photographs and Fundus Fluorescein Angiography (FFA) were performed on all patients using standard fundus camera. All fundus photographs and angiograms were independently reviewed and graded by two qualified vitreoretinal fellows. Results: Out of 258 patients, 163 were males (63.2%) and 95 (36.8%) were females. Average age of patients was 56.30 +- 7.57 years. Average axial length of right and left eyes were 23.16 mm and 23.15 mm respectively. There was statistically significant negative correlation between axial length and severity of diabetic retinopathy in the right eye, (Spearman correlation = -0.511, p = 0.0001) as well as the left eye (Spearman correlation = -0.522, p = 0.0001). Conclusion: There is a protective influence of longer axial length of globe on the stage and severity of diabetic retinopathy. This study may help in modifying the screening protocol for diabetic retinopathy amongst patients of differing axial lengths. (author)

  9. Pharmacologic interventions for the prevention and treatment of retinopathy of prematurity.

    Science.gov (United States)

    Beharry, Kay D; Valencia, Gloria B; Lazzaro, Douglas R; Aranda, Jacob V

    2016-04-01

    Retinopathy of prematurity (ROP), a significant morbidity in prematurely born infants, is the most common cause of visual impairment and blindness in children and persists till adulthood. Strict control of oxygen therapy and prevention of intermittent hypoxia are the keys in the prevention of ROP, but pharmacologic interventions have decreased risk of ROP. Various drug classes such as methylxanthines (caffeine), VEGF inhibitors, antioxidants, and others have decreased ROP occurrence. The timing of pharmacologic intervention remains unsettled, but early prevention rather than controlling disease progression may be preferred. These drugs act through different mechanisms, and synergistic approaches should be considered to maximize efficacy and safety. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Impairment of Colour Vision in Diabetes with No Retinopathy: Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SNDREAMS- II, Report 3.

    Directory of Open Access Journals (Sweden)

    Laxmi Gella

    Full Text Available To assess impairment of colour vision in type 2 diabetics with no diabetic retinopathy and elucidate associated risk factors in a population-based cross-sectional study.This is part of Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular-genetics Study (SN-DREAMS II which was conducted between 2007-2010. FM 100 hue-test was performed in 253 subjects with no clinical evidence of diabetic retinopathy. All subjects underwent detailed ophthalmic evaluation including cataract grading using LOCS III and 45° 4-field stereoscopic fundus photography. Various ocular and systemic risk factors for impairment of colour vision (ICV were assessed in subjects with diabetes but no retinopathy. P value of < 0.05 was considered statistically significant.The mean age of the study sample was 57.08 ± 9.21 (range: 44-86 years. Gender adjusted prevalence of ICV among subjects with diabetes with no retinopathy was 39.5% (CI: 33.5-45.5. The mean total error score in the study sample was 197.77 ± 100 (range: 19-583. The risk factors for ICV in the study were women OR: 1.79 (1.00-3.18, increased resting heart rate OR: 1.04 (1.01-1.07 and increased intraocular pressure OR: 1.12 (1.00-1.24. Significant protective factor was serum high-density lipoprotein OR: 0.96 (0.93-0.99.Acquired ICV is an early indicator of neurodegenerative changes in the retina. ICV found in diabetic subjects without retinopathy may be of non-vascular etiology.

  11. Characteristics of patients with diabetic retinopathy in Gaborone ...

    African Journals Online (AJOL)

    (GLLAMMs) to account for the non-independence of the eye diabetic retinopathy outcome at the patient level (Rabe-Hesketh et al., 2000). This model allowed for analysis of a polytomous ordinal response on a set of predictors and computed the odds ratios (OR) of having a more severe diabetic retinopathy grade compared ...

  12. Detection of Hypertension Retinopathy Using Deep Learning and Boltzmann Machines

    Science.gov (United States)

    Triwijoyo, B. K.; Pradipto, Y. D.

    2017-01-01

    hypertensive retinopathy (HR) in the retina of the eye is disturbance caused by high blood pressure disease, where there is a systemic change of arterial in the blood vessels of the retina. Most heart attacks occur in patients caused by high blood pressure symptoms of undiagnosed. Hypertensive retinopathy Symptoms such as arteriolar narrowing, retinal haemorrhage and cotton wool spots. Based on this reasons, the early diagnosis of the symptoms of hypertensive retinopathy is very urgent to aim the prevention and treatment more accurate. This research aims to develop a system for early detection of hypertension retinopathy stage. The proposed method is to determine the combined features artery and vein diameter ratio (AVR) as well as changes position with Optic Disk (OD) in retinal images to review the classification of hypertensive retinopathy using Deep Neural Networks (DNN) and Boltzmann Machines approach. We choose this approach of because based on previous research DNN models were more accurate in the image pattern recognition, whereas Boltzmann machines selected because It requires speedy iteration in the process of learning neural network. The expected results from this research are designed a prototype system early detection of hypertensive retinopathy stage and analysed the effectiveness and accuracy of the proposed methods.

  13. Spectral domain optical coherence tomography characteristics in diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Laxmi Gella

    2014-01-01

    Full Text Available Purpose: To report the appearance of diabetic retinopathy lesions using spectral domain optical coherence tomography (SD-OCT. Materials and Methods: A total of 287 eyes of 199 subjects were included. All the subjects underwent complete ophthalmic examination including SD-OCT. Results: The appearance of various lesions of diabetic retinopathy and the retinal layers involved were reported. In subjects with macular edema the prevalence of incomplete PVD was 55.6%. Conclusion: SD-OCT brings new insights into the morphological changes of the retina in diabetic retinopathy.

  14. Levels of serum vascular endothelial growth factor in type 2 diabetics with retinopathy

    International Nuclear Information System (INIS)

    Parveen, N.; Rahman, S.; Khan, Q.

    2012-01-01

    Background: Ischemic retina in diabetic patients releases a number of chemical substances including vascular endothelial growth factor which leads to retinal vascular proliferation and blindness following rupture and bleeding of vessels. Strategies to control this action can considerably halt this process. Objectives: To determine the relationship of various stages of diabetic retinopathy with the levels vascular endothelial growth factor in the serum of type 2 diabetic patients. Study type, settings and duration: This cross sectional analytical study was done over one year (2010-2011) in three major public sector hospitals of Peshawar. Patients and Methods: Adult patients of either gender having type 2 diabetes mellitus with proliferative or non proliferative retinopathy and those without retinopathy were selected for the study. Retinopathy was diagnosed on fundoscopy. Non-diabetic patients without retinopathy were selected as controls. Serum levels of vascular endothelial growth factor were done in patients and controls using ELISA. Results: Serum vascular endothelial growth factor levels were significantly higher in all cases having retinopathy as compared to controls. These levels progressively increased with the grades of retinopathy. Levels were higher in females. Conclusions: Levels of vascular endothelial growth factor are raised in diabetic retinopathy and rising levels can alert the clinician in worsening of retinopathy so that preventive and therapeutic measures can be taken promptly. Policy message: Further larger scale studies are recommended on national level to pave way for the establishment of appropriate management paradigms for diabetic retinopathy through anti-VEGF treatment. (author)

  15. Retinal hypoxia induces vascular endothelial growth factor through induction of estrogen-related receptor γ

    Energy Technology Data Exchange (ETDEWEB)

    Do, Ji Yeon; Choi, Young Keun [Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University School of Medicine, Kyungpook National University, Daegu (Korea, Republic of); Kook, Hyun [Department of Pharmacology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Suk, Kyoungho [Department of Pharmacology, Brain Science & Engineering Institute, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Lee, In-Kyu [Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University School of Medicine, Kyungpook National University, Daegu (Korea, Republic of); Division of Endocrinology and Metabolism, Department of Internal Medicine, Research Institute of Aging and Metabolism, Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Park, Dong Ho, E-mail: sarasate2222@gmail.com [Department of Ophthalmology, Kyungpook National University School of Medicine, Daegu (Korea, Republic of)

    2015-05-01

    Ischemic retinopathies causing overexpression of pro-angiogenic factors, including vascular endothelial growth factor (VEGF), are the most common cause of blindness. Thus, understanding the pathophysiology of targetable pathways that regulate retinal VEGF is of great interest. A conserved binding site for estrogen-related receptor γ (ERRγ) has been identified in the promoter of the Vegfa gene. ERRγ is a constitutively active orphan nuclear receptor and its expression is increased by hypoxic stimuli in metabolically active tissues. This study evaluated the role of ERRγ in the ischemic retina and the anti-VEGF potential of GSK5182, a selective inverse agonist of ERRγ. In an oxygen-induced retinopathy (OIR) mouse model, immunohistochemistry showed significantly increased ERRγ expression in the ganglion cell layer at postnatal day (P) 17. In a ganglion cell line (RGC-5), mRNA and protein levels of ERRγ were increased by desferrioxamine treatment and hypoxic conditions (1% O{sub 2}). Transient transfection of RGC-5 cells revealed that ERRγ regulated Vegfa expression and this was inhibited by GSK5182. Intravitreal injection of GSK5182 into the OIR model at P14 inhibited retinal Vegfa mRNA expression at P17. GSK5182 suppresses hypoxia-induced VEGF expression via ERRγ; therefore, ERRγ could be a treatment target for ischemic retinopathies. - Highlights: • OIR mice exhibited increased ERRγ expression in the ganglion cell layer. • Hypoxia-induced ERRγ expression was observed in retinal ganglion cells. • ERRγ overexpression increased VEGFA expression in retinal ganglion cells. • An ERRγ inverse agonist suppressed VEGFA expression in retinal ganglion cells. • Intravitreal injection of an ERRγ inverse agonist suppressed VEGFA in OIR mice.

  16. Retinal hypoxia induces vascular endothelial growth factor through induction of estrogen-related receptor γ

    International Nuclear Information System (INIS)

    Do, Ji Yeon; Choi, Young Keun; Kook, Hyun; Suk, Kyoungho; Lee, In-Kyu; Park, Dong Ho

    2015-01-01

    Ischemic retinopathies causing overexpression of pro-angiogenic factors, including vascular endothelial growth factor (VEGF), are the most common cause of blindness. Thus, understanding the pathophysiology of targetable pathways that regulate retinal VEGF is of great interest. A conserved binding site for estrogen-related receptor γ (ERRγ) has been identified in the promoter of the Vegfa gene. ERRγ is a constitutively active orphan nuclear receptor and its expression is increased by hypoxic stimuli in metabolically active tissues. This study evaluated the role of ERRγ in the ischemic retina and the anti-VEGF potential of GSK5182, a selective inverse agonist of ERRγ. In an oxygen-induced retinopathy (OIR) mouse model, immunohistochemistry showed significantly increased ERRγ expression in the ganglion cell layer at postnatal day (P) 17. In a ganglion cell line (RGC-5), mRNA and protein levels of ERRγ were increased by desferrioxamine treatment and hypoxic conditions (1% O 2 ). Transient transfection of RGC-5 cells revealed that ERRγ regulated Vegfa expression and this was inhibited by GSK5182. Intravitreal injection of GSK5182 into the OIR model at P14 inhibited retinal Vegfa mRNA expression at P17. GSK5182 suppresses hypoxia-induced VEGF expression via ERRγ; therefore, ERRγ could be a treatment target for ischemic retinopathies. - Highlights: • OIR mice exhibited increased ERRγ expression in the ganglion cell layer. • Hypoxia-induced ERRγ expression was observed in retinal ganglion cells. • ERRγ overexpression increased VEGFA expression in retinal ganglion cells. • An ERRγ inverse agonist suppressed VEGFA expression in retinal ganglion cells. • Intravitreal injection of an ERRγ inverse agonist suppressed VEGFA in OIR mice

  17. Global prevalence and major risk factors of diabetic retinopathy

    NARCIS (Netherlands)

    J.W.Y. Yau (Joanne W.); S.L. Rogers (Sophie); Y. Kawasaki; E.L. Lamoureux (Ecosse); J.W. Kowalski (Jonathan); T. Bek (Toke); S.-J. Chen (Shih-Jen); J.M. Dekker (Jacqueline); A.E. Fletcher (Astrid E.); J. Grauslund (Jakob); R.C.G. Haffner; U. Hamman (Ute); M.K. Ikram (Kamran); T. Kayama (Takamasa); B.E.K. Klein (Barbara); B.E.K. Klein (Barbara); S. Krishnaiah (Sannapaneni); K. Mayurasakorn (Korapat); J.P. O'Hare (Joseph); T. Orchard; M. Porta; M. Rema (Mohan); M.S. Roy (Monique); T. Sharma (Tarun); S-M. Saw (Seang-Mei); H. Taylor (Hugh); J.M. Tielsch (James); D. Varma (Dhiraj); J.J. Wang (Jie Jin); N. Wang (Ningli); S. West (Sheila); L. Zu (Liang); M. Yasuda (Maya); X. Zhang (Xinzhi); P. Mitchell (Paul); T.Y. Wong (Tien Yin)

    2012-01-01

    textabstractOBJECTIVE - To examine the global prevalence and major risk factors for diabetic retinopathy (DR) and vision-threatening diabetic retinopathy (VTDR) among people with diabetes. RESEARCH DESIGN AND METHODS - A pooled analysis using individual participant data from population-based studies

  18. Outcomes of vitrectomy for advanced diabetic retinopathy at Groote ...

    African Journals Online (AJOL)

    Background. Present limitations in primary and secondary prevention of diabetic retinopathy mean that many patients with diabetes present with advanced retinal complications, often requiring surgery (vitrectomy). Objectives. To determine the outcomes of vitrectomy for advanced diabetic retinopathy and to examine ...

  19. Bevacizumab treatment for retinopathy of prematurity in South Africa

    African Journals Online (AJOL)

    Retinopathy of prematurity (ROP) is a growing problem in South. Africa (SA), as it is .... detected in the serum of both infants and adults after intraocular injection,[7] ... use of anti-VEGF agents to treat macular degeneration, diabetic retinopathy ...

  20. Changes in serum leptin level in patients with diabetic retinopathy

    International Nuclear Information System (INIS)

    Yu Jing; Cao Huiling

    2003-01-01

    Objective: To explore the regulation of changes in serum leptin level in patients with diabetic retinopathy. Methods: The 120 participating subjects were of four groups: healthy controls, diabetic patients without retinopathy, patients with NPDR and patients with PDR, each group consisted of 18 males and 12 females with comparable BMI. The levels of serum leptin, IVC, insulin and blood glucose of these patients were measured and the correlation between serum leptin level and other parameters was analysed. Results: The level of serum leptin in controls, diabetic patients without retinopathy, patients with NPDR and patients with PDR were 6.91 ± 1.87 μg/L, 7,83 ±2.11 μg/L, 9.56 ± 2.43 μg/L and 11.69 ± 2.57 μg/L respectively. The patients with PDR had higher serum leptin levels than patients with NPDR (t=2.15, p < 0.05), diabetic patients without retinopathy (t = 2.71, p < 0.01), and controls (t = 3.50, p < 0.001), the patients with NPDR had higher serum leptin levels than diabetic patients without retinopathy (t = 2.23, p < 0.05) and controls (t = 2.75, p < 0.01), while the difference in serum leptin was not significant between diabetic patients without retinopathy and controls. The serum level was positively correlated to BMI (r = 0.22, p < 0.05) and FINS (r = 0.28, p < 0.01). Conclusion: Serum leptin level is elevated in patients with diabetic retinopathy and is positively correlated to the severity of the disease

  1. Aggressive posterior retinopathy of prematurity in infants ≥1500 g birth weight

    Directory of Open Access Journals (Sweden)

    Gaurav Sanghi

    2014-01-01

    Full Text Available In this retrospective case series, we report the spectrum and outcomes of aggressive posterior retinopathy of prematurity (APROP in infants ≥1500 g birth weight. Twenty-nine eyes of 15 infants are included. All infants were referred from level I or II nurseries, received supplemental unmonitored oxygen for prolonged duration (>1 week and had multiple systemic co-morbidities. Of the 29 eyes, 10 (34.5% had zone 1 and 19 (65.5% had posterior zone 2 disease. Twenty-five (86.2% eyes had flat neovascularization and 4 (13.8% eyes had brush like proliferation. We noticed large vascular loops in 10 (34.5% eyes. After confluent laser photocoagulation, 22 (75.9% eyes had a favorable outcome. The study concludes that APROP in heavier (≥1500 g birth weight premature infants occurs mostly in posterior zone 2 with flat neovascularization and atypical features like large vascular loops. Supplemental unmonitored oxygen for prolonged duration and multiple systemic co-morbidities could be a contributing factor.

  2. Aggressive posterior retinopathy of prematurity in infants ≥ 1500 g birth weight.

    Science.gov (United States)

    Sanghi, Gaurav; Dogra, Mangat R; Katoch, Deeksha; Gupta, Amod

    2014-02-01

    In this retrospective case series, we report the spectrum and outcomes of aggressive posterior retinopathy of prematurity (APROP) in infants ≥ 1500 g birth weight. Twenty-nine eyes of 15 infants are included. All infants were referred from level I or II nurseries, received supplemental unmonitored oxygen for prolonged duration (>1 week) and had multiple systemic co-morbidities. Of the 29 eyes, 10 (34.5%) had zone 1 and 19 (65.5%) had posterior zone 2 disease. Twenty-five (86.2%) eyes had flat neovascularization and 4 (13.8%) eyes had brush like proliferation. We noticed large vascular loops in 10 (34.5%) eyes. After confluent laser photocoagulation, 22 (75.9%) eyes had a favorable outcome. The study concludes that APROP in heavier (≥ 1500 g birth weight) premature infants occurs mostly in posterior zone 2 with flat neovascularization and atypical features like large vascular loops. Supplemental unmonitored oxygen for prolonged duration and multiple systemic co-morbidities could be a contributing factor.

  3. Voluntary feed intake in rainbow trout is regulated by diet-induced differences in oxygen use.

    Science.gov (United States)

    Saravanan, Subramanian; Geurden, Inge; Figueiredo-Silva, A Cláudia; Kaushik, Sadasivam; Verreth, Johan; Schrama, Johan W

    2013-06-01

    This study investigated the hypothesis that the voluntary feed intake in fish is regulated by diet-induced differences in oxygen use. Four diets were prepared with a similar digestible protein:digestible energy ratio (18 mg/kJ), but which differed in the composition of nonprotein energy source. This replacement of fat (F) by starch (S) was intended to create a diet-induced difference in oxygen use (per unit of feed): diets F30-S70, F50-S50, F65-S35, and F80-S20 with digestible fat providing 28, 49, 65, and 81% of the nonprotein digestible energy (NPDE), respectively. Each diet was fed to satiation to triplicate groups of 20 rainbow trout for 6 wk. As expected, diet-induced oxygen use decreased linearly (R(2) = 0.89; P digestible and metabolizable energy intakes of trout slightly increased with increasing NPDE as fat (i.e., decreasing starch content) (R(2) = 0.30, P = 0.08; and R(2) = 0.34, P = 0.05, respectively). Oxygen consumption of trout fed to satiation declined with increasing dietary NPDE as fat (R(2) = 0.48; P = 0.01). The inverse relation between digestible energy intake of trout and the diet-induced oxygen use (R(2) = 0.33; P = 0.05) suggests a possible role of diet-induced oxygen use in feed intake regulation as shown by the replacement of dietary fat by starch.

  4. Quality assurance for diabetic retinopathy telescreening.

    Science.gov (United States)

    Schneider, S; Aldington, S J; Kohner, E M; Luzio, S; Owens, D R; Schmidt, V; Schuell, H; Zahlmann, G

    2005-06-01

    TOSCA was an EU-Commission supported international research project designed to develop telescreening services in diabetic retinopathy and glaucoma. This paper describes the quality assurance methods developed for the diabetic retinopathy telescreening service within the TOSCA project. The study was performed in 1895 patients with diabetes between 2000 and 2002 at diabetic retinopathy screening sites in five European countries. Data were analysed centrally. Patients attending each clinic's diabetic retinopathy screening service received standardized retinal photography. The images and associated data were transferred electronically to a remote location for grading. Each photographer uploading images and each grader downloading images for assessment was controlled by a systematic quality management approach. The quality assurance measures defined were image quality, intragrader reliability. A cockpit chart was developed for the management and presentation of relevant results and quality measures. For the intragrader reliability tests, 10% of the images were processed for a second grading. An algorithm for calculating differences between repeated gradings was developed. The assessment of image quality for the different sites showed that only 0-0.7% were unassessable. One hundred per cent agreement for both gradings was achieved in 50-85% of graded cases, depending on site and grader, and an agreement better than 95% in 71-100% of cases. A telemedicine-supported quality assurance process is practical and advantageous. The cockpit charts have proven to be useful tools when monitoring the performance of a telescreening service. Grader feedback showed high satisfaction with the quality assurance process.

  5. Endothelin-1 is associated with fibrosis in proliferative diabetic retinopathy membranes.

    Science.gov (United States)

    Chang, William; Lajko, Michelle; Fawzi, Amani A

    2018-01-01

    To characterize the relationship between endothelin-1 and fibrosis in epiretinal membranes in proliferative diabetic retinopathy and explore the role of endothelial-mesenchymal transition in these membranes. Membranes were obtained from eyes undergoing pars plana vitrectomy for complicated proliferative diabetic retinopathy or idiopathic epiretinal membrane. Through standard immunohistochemical techniques, we labeled membranes to explore the distribution of endothelin-1 and endothelin receptor B, comparing proliferative diabetic retinopathy and idiopathic epiretinal membranes. In addition, membranes were also labeled with markers for fibroblasts, endothelial, and glial cells and studied with confocal laser scanning microscopy. The intensity of endothelin-1 labeling was quantified using standard image analysis software. Fourteen membranes were included in the analysis, nine from eyes with proliferative diabetic retinopathy and five idiopathic membranes. Flatmount diabetic membranes showed co-localization of endothelin-1 with S100A4 and CD31. Immunohistochemistry and quantitative analysis of cross-sectional membranes showed significantly higher endothelin-1 labeling in proliferative diabetic retinopathy membranes compared to idiopathic membranes (pmembranes showed more elements staining positive for S100A4 compared to idiopathic membranes. Epiretinal membrane formation in proliferative diabetic retinopathy involves higher tissue levels of endothelin-1 and fibroblastic activity. Furthermore, endothelin-1, endothelial and fibroblastic staining appear to be correlated, suggestive of endothelial-to-mesenchymal transition in proliferative diabetic retinopathy.

  6. Diabetic Retinopathy Awareness among Diabetic Patients Attending COMS-TH.

    Science.gov (United States)

    Dahal, P; Adhikari, H

    Background Diabetic retinopathy (DR) is one of the leading causes of blindness in Nepal. Objective The main objective of the study is to know the awareness of diabetic retinopathy among new cases of diabetes mellitus (DM) attending the college of medical science- teaching hospital, Bharatpur, Nepal. Method All the diabetic cases referred for ophthalmic consultation and also referred outpatient department cases from other departments to ophthalmic outpatient department was carried out. Detailed demographics of the subjects and their awareness of potential ocular problems from diabetes mellitus were noted. Result Total one hundred and thirty-one patients were enrolled during the study period from 15 November 2016 to 15 May 2017. Brahmin 39.69% and 19.08% Mongolian were the most predominant ethnical group. The predominant group of patients were housewives (41.22%) then followed by service (19.85%), business (13.74%), agriculture (12.21%), others (12.98%). Among 36.64% of the literate patients, 19.85% had passed school level, 9.92% had passed intermediate level, 88.55% were aware of Diabetic retinopathy. Among them majority 88.55% were referred by physician. Family history were present in 35.68% and fundus evaluation was done for the first time in almost half of diabetic cases (64.12%) and diabetic retinopathy was found in 32.06% of total cases in right eye and 30.53% of total cases in left eye. Conclusion Along with the awareness, routine dilated fundoscopy is mandatory for slight threating stage of retinopathy and to reduce the burden of blindness from diabetic retinopathy in Nepal.

  7. Radiation Retinopathy: Case report and review

    Directory of Open Access Journals (Sweden)

    Young Lorna

    2007-04-01

    Full Text Available Abstract Background Ocular damage from radiation treatment is a well established phenomenon. Many factors are now known to influence the incidence of radiation retinopathy, including total dosage and daily fraction size. Patients who are diabetic, hypertensive or received previous chemotherapy are more susceptible to radiation retinopathy. Case Presentation A 55 year old male was referred from the oncology department with epiphora. His medical history included Type 2 Insulin treated Diabetes Mellitus and hypertension. One year prior to presentation he had undergone a total rhinectomy with a 4 week course of post-operative radiotherapy for an aggressive sqaumous cell carcinoma of the nose. On examination the visual acuity was noted to be 6/36 left eye and 6/9 right eye. Posterior segment examination revealed marked retinal ischaemia present in the posterior pole and macular region of both eyes. The appearance was not thought to be typical of diabetic changes, radiation retinopathy being the more likely diagnosis especially in view of his history. Over the next four months the vision in both eyes rapidly deteriorated to 3/60 left eye and 1/60 right eye. Bilateral pan retinal photocoagulation was thought to be appropriate treatment at this point. Conclusion This case highlights the importance for ophthalmologists and oncologists to be aware of the close relationship between diabetes and radiation treatment and the profound rapid impact this combination of factors may have on visual function. Radiation is being used with increasing frequency for ocular and orbital disease, because of this more cases of radiation retinopathy may become prevalent. Factors which may potentiate radiation retinopathy should be well known including, increased radiation dosage, increased fraction size, concomitant systemic vascular disease and use of chemotherapy. Counselling should be offered in all cases at risk of visual loss. As no effective treatment currently exists

  8. Thickness of the retinal photoreceptor outer segment layer in healthy volunteers and in patients with diabetes mellitus without retinopathy, diabetic retinopathy, or diabetic macular edema

    Directory of Open Access Journals (Sweden)

    Abdullah Ozkaya

    2017-04-01

    Conclusion: The PROS layer at the foveal center was thinner in patients who had diabetic retinopathy or diabetic macular edema than both the healthy volunteers and diabetic patients without retinopathy.

  9. Radiation retinopathy following treatment of posterior nasal space carcinoma

    International Nuclear Information System (INIS)

    Thompson, G.M.; Migdal, C.S.; Whittle, R.J.M.

    1983-01-01

    Posterior nasal space carcinoma has a high mortality and most patents are treated with radiotherapy. Radiation retinopathy was encountered in 7 out of 10 survivors included in this study. Five of the affected patients lost vision as a result of the retinopathy. One patient required laser photocoagulation and responded well to this treatment. There was a variation in the severity of the retinopathy among the patients studied despite the fact that all patients received a similar dose of radiotherapy. We suspect that previously unrecognised factors in the planning of radiotherapy fields may explain this difference. (author)

  10. Automated detection of fundus photographic red lesions in diabetic retinopathy.

    Science.gov (United States)

    Larsen, Michael; Godt, Jannik; Larsen, Nicolai; Lund-Andersen, Henrik; Sjølie, Anne Katrin; Agardh, Elisabet; Kalm, Helle; Grunkin, Michael; Owens, David R

    2003-02-01

    To compare a fundus image-analysis algorithm for automated detection of hemorrhages and microaneurysms with visual detection of retinopathy in patients with diabetes. Four hundred fundus photographs (35-mm color transparencies) were obtained in 200 eyes of 100 patients with diabetes who were randomly selected from the Welsh Community Diabetic Retinopathy Study. A gold standard reference was defined by classifying each patient as having or not having diabetic retinopathy based on overall visual grading of the digitized transparencies. A single-lesion visual grading was made independently, comprising meticulous outlining of all single lesions in all photographs and used to develop the automated red lesion detection system. A comparison of visual and automated single-lesion detection in replicating the overall visual grading was then performed. Automated red lesion detection demonstrated a specificity of 71.4% and a resulting sensitivity of 96.7% in detecting diabetic retinopathy when applied at a tentative threshold setting for use in diabetic retinopathy screening. The accuracy of 79% could be raised to 85% by adjustment of a single user-supplied parameter determining the balance between the screening priorities, for which a considerable range of options was demonstrated by the receiver-operating characteristic (area under the curve 90.3%). The agreement of automated lesion detection with overall visual grading (0.659) was comparable to the mean agreement of six ophthalmologists (0.648). Detection of diabetic retinopathy by automated detection of single fundus lesions can be achieved with a performance comparable to that of experienced ophthalmologists. The results warrant further investigation of automated fundus image analysis as a tool for diabetic retinopathy screening.

  11. [Outcomes of surgical management of retinopathy of prematurity--an overview].

    Science.gov (United States)

    Kuprjanowicz, Leszek; Kubasik-Kładna, Katarzyna; Modrzejewska, Monika

    2014-01-01

    According to the guidelines by the ETROP (Early Treatment for Retinopathy of Prematurity) study group, laser therapy is the gold standard in the treatment of retinopathy of prematurity. However, progression of the disease is seen in 12% of eyes despite the treatment. Since there is no causal treatment, new therapies of retinopathy of prematurity, are continually sought, such as anti-VEGF agents, beta-blockers, or insulin-like growth factor gene therapy. In cases with concomitant retinal detachment, surgery is performed. The standard therapy for retinopathy of prematurity stages 4-5 involves pars plicata vitrectomy and lensectomy (stage 5), ab externo surgery (scleral buckling) and lens-sparing vitrectomy (some cases of stage 4). Classic vitrectomy with lensectomy is reserved only for cases with advanced retinal tractions, retina-lens apposition or for cases of intraoperative lens damage during the lens-sparing vitrectomy. The ab externo surgery does not eliminate vitreous tractions, but it stabilises the neovascular membrane activity (transforming it into a scar). The indication for this type of operation is stage 4 retinopathy of prematurity with peripheral proliferations, except for the posterior--aggressive form of retinopathy of prematurity. Many papers have been published on combined therapy involving vitrectomy and conservative treatment. In conclusion, optimal timing of surgical intervention is difficult to determine in stages 4 and 5, because the anatomical and functional outcomes in stage 5 are unfavourable. Both, ab externo surgery and vitrectomy tend to produce poor macular vision in eyes with advanced retinopathy of prematurity, therefore surgical intervention at stage 4 just before the local macular retinal detachment provides better anatomical and functional outcomes.

  12. Frequency of diabetic retinopathy in karachi, pakistan: a hospital based study

    International Nuclear Information System (INIS)

    Alkhairy, S.; Rasheed, A.

    2015-01-01

    This study was conducted to determine the prevalence of diabetic retinopathy in diabetes patients presenting to the National Institute of Diabetes and Eye out patient department of Dow University Hospital (Ohja campus), Dow University of Health Sciences. Materials and Methods: This was a cross sectional study in which known diabetics were recruited between the period of 1st July 2011 till 31st July 2012.They were then referred to the Ophthalmology unit for eye examination. Subjective refraction was done with Snellens chart, anterior segment examination and fundus examined was done using a TopCon PS-61E Slit lamp BioMicroscope. All patients were dilated with eye drop tropicamide 1% instilled every ten minutes for thirty minutes and the fundus was examined with Volk 90D lens. Classification of diabetic retinopathy was done using the International clinical diabetic retinopathy disease severity scale study. The data was analyzed using Statistical package for social Science (SPSS version 20) and a p value of < 0.05 was taken as statistically significant. Results: There were a total number of 570 patients included in this study. Amongst them 325 were males and 245 were females. Out of these patients those that who were found to have diabetic retinopathy were 315 (55.3%).The age range was between 25 and 75 years and the mean age was 52.30 ± 9.333.Patients that were found to have mild non proliferative diabetic retinopathy were 231(40.5% ) while 33 (5.8%) had moderate non-proliferative diabetic retinopathy,11(1.9%) had severe non-proliferative diabetic retinopathy and 40 (7.0)% had proliferative diabetic retinopathy. Diabetic Maculopathy was seen in a total number of 72(12.6%) of patients. Conclusions: Diabetic retinopathy is highly prevalent in Karachi, Pakistan thus it is vital to detect as well as manage the disease early so as to prevent the onset of blindness in relation to it. (author)

  13. Early diagnosis of sub-clinical stage of diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Xing-Hui Xu

    2014-12-01

    Full Text Available AIM: To evaluate the early diagnosis of sub-clinic stage of diabetic retinopathy.METHODS: This was cross sectional study,multifocal retina electroretinogram(mf-ERG, contrast sensitivity(CSand central retinal artery color Doppler examination were recorded from 30 cases(30 eyesmatched control subjects, 35 cases(35 eyeswith type 2 diabetes mellitus(DMwithout diabetic retinopathy(NDRand 38 cases(38 eyeswith non-prolifera tive diabetic retinopathy(NPDR. One-way ANOVA and SNK-q test were used for data analysis.RESULTS: P1 response density of NDR patients were found decrease, N1 implicit time were delayed. Which were related with the degree of retinopathy(PPPP>0.05, The differences between normal group, NDR group and NPDR group were found statistically significant(PCONCLUSION: mf-ERG and CS are sensitive indexes for early evaluation of visual function in patients with diabetes mellitus, with development of the disease, CRA blood flow also appears to decline.

  14. The North Jutland County Diabetic Retinopathy Study (NCDRS). Population characteristics

    DEFF Research Database (Denmark)

    Knudsen, L.L.; Lervang, H.H.; Lundbye-Christensen, Søren

    Abstract Purpose: Several population based studies have reported blood glucose levels and blood pressure to be risk factors for the development of proliferativ retinopathy and diabetic maculopathy. Despite their importance, these studies were initiated more than two decades ago and may therefore...... reflect the treatment and population composition of a previous era. Studies of the present diabetic population are therefore in demand. Methods: The present cross–section study included 656 type 1 and 328 type 2 diabetic subjects undergoing diabetic retinopathy screening. Crude prevalence rates...... for proliferative diabetic retinopathy, maculopathy, several specific lesions and non–ophthalmic findings were assessed together with their association to a simplified and internationally approved retinal grading. Results: The crude prevalence of proliferative retinopathy was found to be 5.6 % and 0.9 % for type 1...

  15. The Diabetic Retinopathy Screening Workflow

    Science.gov (United States)

    Bolster, Nigel M.; Giardini, Mario E.; Bastawrous, Andrew

    2015-01-01

    Complications of diabetes mellitus, namely diabetic retinopathy and diabetic maculopathy, are the leading cause of blindness in working aged people. Sufferers can avoid blindness if identified early via retinal imaging. Systematic screening of the diabetic population has been shown to greatly reduce the prevalence and incidence of blindness within the population. Many national screening programs have digital fundus photography as their basis. In the past 5 years several techniques and adapters have been developed that allow digital fundus photography to be performed using smartphones. We review recent progress in smartphone-based fundus imaging and discuss its potential for integration into national systematic diabetic retinopathy screening programs. Some systems have produced promising initial results with respect to their agreement with reference standards. However further multisite trialling of such systems’ use within implementable screening workflows is required if an evidence base strong enough to affect policy change is to be established. If this were to occur national diabetic retinopathy screening would, for the first time, become possible in low- and middle-income settings where cost and availability of trained eye care personnel are currently key barriers to implementation. As diabetes prevalence and incidence is increasing sharply in these settings, the impact on global blindness could be profound. PMID:26596630

  16. Proliferative diabetic retinopathy is associated with microalbuminuria in patients with type 2 diabetes

    Directory of Open Access Journals (Sweden)

    M.C. Boelter

    2006-08-01

    Full Text Available Diabetic retinopathy is one of the leading causes of blindness in working-age individuals. Diabetic patients with proteinuria or those on dialysis usually present severe forms of diabetic retinopathy, but the association of diabetic retinopathy with early stages of diabetic nephropathy has not been entirely established. A cross-sectional study was conducted on 1214 type 2 diabetic patients to determine whether microalbuminuria is associated with proliferative diabetic retinopathy in these patients. Patients were evaluated by direct and indirect ophthalmoscopy and grouped according to the presence or absence of proliferative diabetic retinopathy. The agreement of diabetic retinopathy classification performed by ophthalmoscopy and by stereoscopic color fundus photographs was 95.1% (kappa = 0.735; P < 0.001. Demographic information, smoking history, anthropometric and blood pressure measurements, glycemic and lipid profile, and urinary albumin were evaluated. On multiple regression analysis, diabetic nephropathy (OR = 5.18, 95% CI = 2.91-9.22, P < 0.001, insulin use (OR = 2.52, 95% CI = 1.47-4.31, P = 0.001 and diabetes duration (OR = 1.04, 95% CI = 1.01-1.07, P = 0.011 were positively associated with proliferative diabetic retinopathy, and body mass index (OR = 0.90, 95% CI = 0.86-0.96, P < 0.001 was negatively associated with it. When patients with macroalbuminuria and on dialysis were excluded, microalbuminuria (OR = 3.3, 95% CI = 1.56-6.98, P = 0.002 remained associated with proliferative diabetic retinopathy. Therefore, type 2 diabetic patients with proliferative diabetic retinopathy more often presented renal involvement, including urinary albumin excretion within the microalbuminuria range. Therefore, all patients with proliferative diabetic retinopathy should undergo an evaluation of renal function including urinary albumin measurements.

  17. Social and emotional impact of diabetic retinopathy: a review.

    Science.gov (United States)

    Fenwick, Eva; Rees, Gwyn; Pesudovs, Konrad; Dirani, Mohamed; Kawasaki, Ryo; Wong, Tien Y; Lamoureux, Ecosse

    2012-01-01

    People with vision-threatening diabetic retinopathy are likely to experience enhanced social and emotional strain. Critically, those with both vision-threatening diabetic retinopathy and psychosocial problems may have significantly reduced levels of functioning compared with psychologically healthy counterparts. This can cause inadequate compliance, increased strain on family functioning, worse diabetes control, increased progression of diabetic retinopathy and, consequently, further psychosocial stress resulting in a number of concerning implications for disease management, clinical outcomes and healthcare costs. However, the emotional and social health consequences of diabetic retinopathy have not yet been systematically explored. This information is crucial as it allows for a targeted approach to treatment and prevention and avoidance of the potentially detrimental implications described above. Therefore, this paper reviews the current qualitative and quantitative evidence regarding the social and emotional impact of diabetic retinopathy and identifies directions for future research. Key search terms were applied to the electronic databases Pubmed, ISI Web of Science and Embase and the bibliographies of relevant papers were systematically reviewed for additional references. Overall, the evidence suggests that diabetic retinopathy and associated vision loss have several debilitating effects, including disruption of family functioning, relationships and roles; increased social isolation and dependence; and deterioration of work prospects resulting in increased financial strain. Adverse emotional responses include fear, anxiety, vulnerability, guilt, loss of confidence, anger, stress and self-perception issues. However, the research to date is largely qualitative in nature, with most quantitative studies being small, cross-sectional and somewhat outdated. Similarly, the outcome measures used in many studies to date are suboptimal in terms of content and validity

  18. Tiam1-Rac1 Axis Promotes Activation of p38 MAP Kinase in the Development of Diabetic Retinopathy: Evidence for a Requisite Role for Protein Palmitoylation

    Directory of Open Access Journals (Sweden)

    Rajakrishnan Veluthakal

    2015-04-01

    Full Text Available Background/Aims: Evidence in multiple tissues, including retina, suggests generation of reactive oxygen species (ROS and the ensuing oxidative stress as triggers for mitochondrial defects and cell apoptosis. We recently reported novel roles for Tiam1-Rac1-Nox2 axis in retinal mitochondrial dysfunction and cell death leading to the development of diabetic retinopathy. Herein, we tested the hypothesis that activation of p38 MAP kinase, a stress kinase, represents the downstream signaling event to Rac1-Nox2 activation in diabetes-induced metabolic stress leading to capillary cell apoptosis. Methods: Activation of p38 MAP kinase was quantified by Western blotting in retinal endothelial cells incubated with high glucose (20 mM for up to 96 hours, a duration where mitochondrial dysfunction and capillary cell apoptosis can be observed. NSC23766 and 2-bromopalmitate (2-BP were used to assess the roles of Tiam1-Rac1 and palmitoylation pathways, respectively. Results: Activation of p38 MAP kinase was observed as early as 3 hours after high glucose exposure, and continued until 96 hours. Consistent with this, p38 MAP kinase activation was significantly higher in the retina from diabetic mice compared to age-matched normal mice. NSC23766 markedly attenuated hyperglycemia-induced activation of p38 MAP kinase. Lastly, 2-BP inhibited glucose-induced Rac1, Nox2 and p38 MAP kinase activation in endothelial cells. Conclusions: Tiam1-Rac1-mediated activation of Nox2 and p38 MAP kinase constitutes early signaling events leading to mitochondrial dysfunction and the development of diabetic retinopathy. Our findings also provide the first evidence to implicate novel roles for protein palmitoylation in this signaling cascade.

  19. Multicolor Scanning Laser Imaging in Diabetic Retinopathy.

    Science.gov (United States)

    Ahmad, Mohammad S Z; Carrim, Zia Iqbal

    2017-11-01

    Diabetic retinopathy is a common cause of blindness in individuals younger than 60 years. Screening for retinopathy is undertaken using conventional color fundus photography and relies on the identification of hemorrhages, vascular abnormalities, exudates, and cotton-wool spots. These can sometimes be difficult to identify. Multicolor scanning laser imaging, a new imaging modality, may have a role in improving screening outcomes, as well as facilitating treatment decisions. Observational case series comprising two patients with known diabetes who were referred for further examination after color fundus photography revealed abnormal findings. Multicolor scanning laser imaging was undertaken. Features of retinal disease from each modality were compared. Multicolor scanning laser imaging provides superior visualization of retinal anatomy and pathology, thereby facilitating risk stratification and treatment decisions. Multicolor scanning laser imaging is a novel imaging technique offering the potential for improving the reliability of screening for diabetic retinopathy. Validation studies are warranted.

  20. Neurodegeneration and Neuroprotection in Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Abdullah S. Alhomida

    2013-01-01

    Full Text Available Diabetic retinopathy is widely considered to be a neurovascular disease. This is in contrast to its previous identity as solely a vascular disease. Early in the disease progression of diabetes, the major cells in the neuronal component of the retina consist of retinal ganglion cells and glial cells, both of which have been found to be compromised. A number of retinal function tests also indicated a functional deficit in diabetic retina, which further supports dysfunction of neuronal cells. As an endocrinological disorder, diabetes alters metabolism both systemically and locally in several body organs, including the retina. A growing body of evidences indicates increased levels of excitotoxic metabolites, including glutamate, branched chain amino acids and homocysteine in cases of diabetic retinopathy. Also present, early in the disease, are decreased levels of folic acid and vitamin-B12, which are potential metabolites capable of damaging neurons. These altered levels of metabolites are found to activate several metabolic pathways, leading to increases in oxidative stress and decreases in the level of neurotrophic factors. As a consequence, they may damage retinal neurons in diabetic patients. In this review, we have discussed those potential excitotoxic metabolites and their implications in neuronal damage. Possible therapeutic targets to protect neurons are also discussed. However, further research is needed to understand the exact molecular mechanism of neurodegeneration so that effective neuroprotection strategies can be developed. By protecting retinal neurons early in diabetic retinopathy cases, damage of retinal vessels can be protected, thereby helping to ameliorate the progression of diabetic retinopathy, a leading cause of blindness worldwide.

  1. Prevalence and 25 year incidence of proliferative retinopathy among Danish type 1 diabetic patients

    DEFF Research Database (Denmark)

    Grauslund, J; Green, A; Sjølie, A K

    2009-01-01

    AIMS/HYPOTHESIS: This study aimed to evaluate the prevalence of retinopathy in long-surviving type 1 diabetic patients. It also investigated the 25 year incidence of proliferative retinopathy and associated risk factors in a Danish population-based cohort. METHODS: A population-based cohort of 727...... type 1 diabetic patients from Fyn County, Denmark, was identified in 1973. In 1981-1982, baseline retinopathy was graded and other risk factors were assessed in 573 patients. Twenty-five years later, 308 patients were still alive. Of these, 201 (65.3%) were re-examined at follow-up in 2007......-2008. RESULTS: The median age and duration of diabetes at follow-up were 58.8 and 43 years, respectively. At follow-up, the prevalence of diabetic retinopathy was 97.0%. Non-proliferative retinopathy was found in 45.8%, and 51.2% had proliferative retinopathy. The 25 year incidence of proliferative retinopathy...

  2. Zone 1 retinopathy of prematurity in a transitional economy: a cautionary note.

    Science.gov (United States)

    Carden, Susan M; Lan, Luu Ngoc; Huynh, Tess

    2006-06-01

    To describe three low risk infants in whom severe retinopathy of prematurity developed. A prospective, observational case series. setting: National Hospital of Pediatrics, Hanoi, Vietnam. study population: Premature infants in the neonatal ward. observation procedure: Eye examinations. Severe retinopathy of prematurity occurred in three infants. All had zone 1 disease and other unusually severe findings, such as neovascularization of the disk. These infants would not be at risk for the development of such severe retinopathy of prematurity in countries with a developed economy. Unusual characteristics of retinopathy of prematurity may be occurring in countries with transitional economies. Screening programs should be implemented and should take into consideration the possibility that retinopathy of prematurity may occur in infants who fall outside the screening guidelines that are used in the developed world.

  3. Diabetic Retinopathy Is Associated With Elevated Serum Asymmetric and Symmetric Dimethylarginines

    OpenAIRE

    Abhary, Sotoodeh; Kasmeridis, Nicholas; Burdon, Kathryn P.; Kuot, Abraham; Whiting, Malcolm J.; Yew, Wai Ping; Petrovsky, Nikolai; Craig, Jamie E.

    2009-01-01

    OBJECTIVE Asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA), and l-arginine directly influence nitric oxide production. Our objective was to test whether serum ADMA, SDMA, or l-arginine levels correlate with diabetic retinopathy subtype or severity. RESEARCH DESIGN AND METHODS A total of 162 subjects with type 1 diabetes and 343 with type 2 diabetes, of whom 329 subjects had no diabetic retinopathy, 27 had nonproliferative diabetic retinopathy (NPDR), 101 had proliferative...

  4. Grade III or Grade IV Hypertensive Retinopathy with Severely Elevated Blood Pressure

    Directory of Open Access Journals (Sweden)

    Amanda D Henderson

    2012-12-01

    Full Text Available Introduction: Hypertensive retinopathy describes a spectrum of retinal changes in patients with elevated blood pressure (BP. It is unknown why some patients are more likely to develop acute ocular end-organ damage than others with similar BP. We examined risk factors for grade III/IV hypertensive retinopathy among patients with hypertensive urgency in the emergency department (ED and compared healthcare utilization and mortality between patients with and without grade III/IV hypertensive retinopathy.Methods: A preplanned subanalysis of patients who presented to a university hospital ED with diastolic BP > 120 mmHg and who enrolled in the Fundus Photography versus Ophthalmoscopy Trial Outcomes in the ED study was performed. Bilateral nonmydriatic ocular fundus photographs, vital signs, and demographics were obtained at presentation. Past medical history, laboratory values, healthcare utilization, and mortality were ascertained from medical record review at least 8 months after initial ED visit.Results: Twenty-one patients with diastolic BP > 120 mmHg, 7 of whom (33% had grade III/IV hypertensive retinopathy, were included. Patients with retinopathy were significantly younger than those without (median 33 vs 50 years, P = 0.02. Mean arterial pressure (165 vs 163 mmHg was essentially equal in the 2 groups. Patients with retinopathy had substantially increased but nonsignificant rates of ED revisit (57% vs 29%, P = 0.35 and hospital admission after ED discharge (43% vs 14%, P = 0.28. One of the patients with retinopathy died, but none without.Conclusion: Younger patients may be at higher risk for grade III/IV hypertensive retinopathy among patients with hypertensive urgency. Chronic compensatory mechanisms may have not yet developed in these younger patients. Alternatively, older patients with retinopathy may be underrepresented secondary to increased mortality among these patients at a younger age (survivorship bias. Further research is needed to

  5. barriers to an effective diabetic retinopathy service in ibadan, nigeria

    African Journals Online (AJOL)

    like UK and USA,6,7 barriers identified include fear of ... blindness as well as the cost of attending clinic. Diabetic retinopathy .... cost of treatment for diabetic retinopathy - laser treatment ..... harness compliance to diabetic care, treatment and.

  6. DIAGNOSIS OF DIABETIC RETINOPATHY USING MACHINE LEARNING TECHNIQUES

    Directory of Open Access Journals (Sweden)

    R. Priya

    2013-07-01

    Full Text Available Diabetic retinopathy (DR is an eye disease caused by the complication of diabetes and we should detect it early for effective treatment. As diabetes progresses, the vision of a patient may start to deteriorate and lead to diabetic retinopathy. As a result, two groups were identified, namely non-proliferative diabetic retinopathy (NPDR and proliferative diabetic retinopathy (PDR. In this paper, to diagnose diabetic retinopathy, three models like Probabilistic Neural network (PNN, Bayesian Classification and Support vector machine (SVM are described and their performances are compared. The amount of the disease spread in the retina can be identified by extracting the features of the retina. The features like blood vessels, haemmoraghes of NPDR image and exudates of PDR image are extracted from the raw images using the image processing techniques and fed to the classifier for classification. A total of 350 fundus images were used, out of which 100 were used for training and 250 images were used for testing. Experimental results show that PNN has an accuracy of 89.6 % Bayes Classifier has an accuracy of 94.4% and SVM has an accuracy of 97.6%. This infers that the SVM model outperforms all other models. Also our system is also run on 130 images available from “DIARETDB0: Evaluation Database and Methodology for Diabetic Retinopathy” and the results show that PNN has an accuracy of 87.69% Bayes Classifier has an accuracy of 90.76% and SVM has an accuracy of 95.38%.

  7. Does bariatric surgery prevent progression of diabetic retinopathy?

    Science.gov (United States)

    Chen, Y; Laybourne, J P; Sandinha, M T; de Alwis, N M W; Avery, P; Steel, D H

    2017-08-01

    PurposeTo assess the changes in diabetic retinopathy (DR) in type 2 diabetes (T2DM) patients post bariatric surgery and report on the risk factors that may be associated with it.Patients and methodsRetrospective observational study of T2DM patients who underwent bariatric surgery in a UK specialist bariatric unit between 2009 and 2015. Preoperative and postoperative weight, HbA1c, and annual DR screening results were collected from medical records. Patients with preoperative retinal screening and at least one postoperative retinal screening were eligible for analysis. Multivariate analysis was used to explore significant clinical predictors on postoperative worsening in DR.ResultsA total of 102 patients were eligible for analysis and were followed up for 4 years. Preoperatively, 68% of patients had no DR compared to 30% with background retinopathy, 1% pre-proliferative retinopathy, and 1% proliferative retinopathy. In the first postoperative visit, 19% of patients developed new DR compared to 70% stable and 11% improved. These proportions remained similar for each postoperative visit over time. Young age, male gender, high preoperative HbA1c, and presence of preoperative retinopathy were the significant predictors of worsening postoperatively.ConclusionBariatric surgery does not prevent progression of DR. Young male patients with pre-existing DR and poor preoperative glycaemic control are most at risk of progression. All diabetic patients should attend regular DR screening post bariatric surgery to allow early detection of potentially sight-threatening changes, particularly among those with identifiable risk factors. Future prospective studies with prolonged follow-up are required to clarify the duration of risk.

  8. Role of advanced glycation end products (AGEs) and oxidative stress in diabetic retinopathy.

    Science.gov (United States)

    Yamagishi, Sho-ichi; Ueda, Seiji; Matsui, Takanori; Nakamura, Kazuo; Okuda, Seiya

    2008-01-01

    Diabetic retinopathy is a common and potentially devastating microvascular complication in diabetes and is a leading cause of acquired blindness among the people of occupational age. However, current therapeutic options for the treatment of sight-threatening proliferative diabetic retinopathy such as photocoagulation and vitrectomy are limited by considerable side effects and far from satisfactory. Therefore, to develop novel therapeutic strategies that specifically target diabetic retinopathy is actually desired for most of the patients with diabetes. Chronic hyperglycemia is a major initiator of diabetic retinopathy. However, recent clinical study has substantiated the concept of 'hyperglycemic memory' in the pathogenesis of diabetic retinopathy. Indeed, the Diabetes Control and Complications Trial-Epidemiology of Diabetes Interventions and Complications (DCCT-EDIC) Research, has revealed that the reduction in the risk of progressive retinopathy resulting from intensive therapy in patients with type 1 diabetes persisted for at least several years after the DCCT trial, despite increasing hyperglycemia. These findings suggest a long-term beneficial influence of early metabolic control on clinical outcomes in type 1 diabetic patients. Among various biochemical pathways implicated in the pathogenesis of diabetic retinopathy, the process of formation and accumulation of advanced glycation end products (AGEs) and their mode of action are most compatible with the theory 'hyperglycemic memory'. Further, there is a growing body of evidence that AGEs-RAGE (receptor for AGEs) interaction-mediated oxidative stress generation plays an important role in diabetic retinopathy. This article summarizes the role of AGEs and oxidative stress in the development and progression of diabetic retinopathy and the therapeutic interventions that could prevent this devastating disorder. We also discuss here the pathological crosstalk between the AGEs-RAGE and the renin-angiotensin system in

  9. Evidence from a natural experiment that malaria parasitemia is pathogenic in retinopathy-negative cerebral malaria.

    Science.gov (United States)

    Small, Dylan S; Taylor, Terrie E; Postels, Douglas G; Beare, Nicholas Av; Cheng, Jing; MacCormick, Ian Jc; Seydel, Karl B

    2017-06-07

    Cerebral malaria (CM) can be classified as retinopathy-positive or retinopathy-negative, based on the presence or absence of characteristic retinal features. While malaria parasites are considered central to the pathogenesis of retinopathy-positive CM, their contribution to retinopathy-negative CM is largely unknown. One theory is that malaria parasites are innocent bystanders in retinopathy-negative CM and the etiology of the coma is entirely non-malarial. Because hospitals in malaria-endemic areas often lack diagnostic facilities to identify non-malarial causes of coma, it has not been possible to evaluate the contribution of malaria infection to retinopathy-negative CM. To overcome this barrier, we studied a natural experiment involving genetically inherited traits, and find evidence that malaria parasitemia does contribute to the pathogenesis of retinopathy-negative CM. A lower bound for the fraction of retinopathy-negative CM that would be prevented if malaria parasitemia were to be eliminated is estimated to be 0.93 (95% confidence interval: 0.68, 1).

  10. Neonatal hyperglycemia inhibits angiogenesis and induces inflammation and neuronal degeneration in the retina.

    Directory of Open Access Journals (Sweden)

    Elsa Kermorvant-Duchemin

    Full Text Available Recent evidence suggests that transient hyperglycemia in extremely low birth weight infants is strongly associated with the occurrence of retinopathy of prematurity (ROP. We propose a new model of Neonatal Hyperglycemia-induced Retinopathy (NHIR that mimics many aspects of retinopathy of prematurity. Hyperglycemia was induced in newborn rat pups by injection of streptozocine (STZ at post natal day one (P1. At various time points, animals were assessed for vascular abnormalities, neuronal cell death and accumulation and activation of microglial cells. We here report that streptozotocin induced a rapid and sustained increase of glycemia from P2/3 to P6 without affecting rat pups gain weight or necessitating insulin treatment. Retinal vascular area was significantly reduced in P6 hyperglycemic animals compared to control animals. Hyperglycemia was associated with (i CCL2 chemokine induction at P6, (ii a significant recruitment of inflammatory macrophages and an increase in total number of Iba+ macrophages/microglia cells in the inner nuclear layer (INL, and (iii excessive apoptosis in the INL. NHIR thereby reproduces several aspects of ischemic retinopathies, including ROP and diabetic retinopathies, and might be a useful model to decipher hyperglycemia-induced cellular and molecular mechanisms in the small rodent.

  11. Hemorrhagic Retinopathy after Spondylosis Surgery and Seizure.

    Science.gov (United States)

    Kord Valeshabad, Ali; Francis, Andrew W; Setlur, Vikram; Chang, Peter; Mieler, William F; Shahidi, Mahnaz

    2015-08-01

    To report bilateral hemorrhagic retinopathy in an adult female subject after lumbar spinal surgery and seizure. A 38-year-old woman presented with bilateral blurry vision and spots in the visual field. The patient had lumbar spondylosis surgery that was complicated by a dural tear with persistent cerebrospinal fluid leak. Visual symptoms started immediately after witnessed seizure-like activity. At presentation, visual acuity was 20/100 and 20/25 in the right and left eye, respectively. Dilated fundus examination demonstrated bilateral hemorrhagic retinopathy with subhyaloid, intraretinal, and subretinal involvement. At 4-month follow-up, visual acuity improved to 20/60 and 20/20 in the right and left eye, respectively. Dilated fundus examination and fundus photography showed resolution of retinal hemorrhages in both eyes. The first case of bilateral hemorrhagic retinopathy after lumbar spondylosis surgery and witnessed seizure in an adult was reported. Ophthalmic examination may be warranted after episodes of seizure in adults.

  12. Machine Learning Approaches for Detecting Diabetic Retinopathy from Clinical and Public Health Records.

    Science.gov (United States)

    Ogunyemi, Omolola; Kermah, Dulcie

    2015-01-01

    Annual eye examinations are recommended for diabetic patients in order to detect diabetic retinopathy and other eye conditions that arise from diabetes. Medically underserved urban communities in the US have annual screening rates that are much lower than the national average and could benefit from informatics approaches to identify unscreened patients most at risk of developing retinopathy. Using clinical data from urban safety net clinics as well as public health data from the CDC's National Health and Nutrition Examination Survey, we examined different machine learning approaches for predicting retinopathy from clinical or public health data. All datasets utilized exhibited a class imbalance. Classifiers learned on the clinical data were modestly predictive of retinopathy with the best model having an AUC of 0.72, sensitivity of 69.2% and specificity of 55.9%. Classifiers learned on public health data were not predictive of retinopathy. Successful approaches to detecting latent retinopathy using machine learning could help safety net and other clinics identify unscreened patients who are most at risk of developing retinopathy and the use of ensemble classifiers on clinical data shows promise for this purpose.

  13. Radiation retinopathy

    International Nuclear Information System (INIS)

    Wara, W.M.; Irvine, A.R.; Neger, R.E.; Howes, E.L. Jr.; Phillips, T.L.

    1979-01-01

    The records were reviewed of all patients treated with irradiation to the eye at the University of California, San Francisco, between 1960 and 1975. Eight patients were identified who had developed radiation retinopathy 1 to 3 years postrirradiation. Lesions included retinal vascular occlusions, hemorrhages, microaneurysms, exudates, neovascularization, vitreous hemorrhage, retinal detachments, and optic atrophy with blindness. Four patients had received less than 5000 rad in 6 weeks to the retina, a dose usually considered within normal tissue tolerance

  14. Development of a screening tool for staging of diabetic retinopathy in fundus images

    Science.gov (United States)

    Dhara, Ashis Kumar; Mukhopadhyay, Sudipta; Bency, Mayur Joseph; Rangayyan, Rangaraj M.; Bansal, Reema; Gupta, Amod

    2015-03-01

    Diabetic retinopathy is a condition of the eye of diabetic patients where the retina is damaged because of long-term diabetes. The condition deteriorates towards irreversible blindness in extreme cases of diabetic retinopathy. Hence, early detection of diabetic retinopathy is important to prevent blindness. Regular screening of fundus images of diabetic patients could be helpful in preventing blindness caused by diabetic retinopathy. In this paper, we propose techniques for staging of diabetic retinopathy in fundus images using several shape and texture features computed from detected microaneurysms, exudates, and hemorrhages. The classification accuracy is reported in terms of the area (Az) under the receiver operating characteristic curve using 200 fundus images from the MESSIDOR database. The value of Az for classifying normal images versus mild, moderate, and severe nonproliferative diabetic retinopathy (NPDR) is 0:9106. The value of Az for classification of mild NPDR versus moderate and severe NPDR is 0:8372. The Az value for classification of moderate NPDR and severe NPDR is 0:9750.

  15. The role of haemorrhage and exudate detection in automated grading of diabetic retinopathy.

    Science.gov (United States)

    Fleming, Alan D; Goatman, Keith A; Philip, Sam; Williams, Graeme J; Prescott, Gordon J; Scotland, Graham S; McNamee, Paul; Leese, Graham P; Wykes, William N; Sharp, Peter F; Olson, John A

    2010-06-01

    Automated grading has the potential to improve the efficiency of diabetic retinopathy screening services. While disease/no disease grading can be performed using only microaneurysm detection and image-quality assessment, automated recognition of other types of lesions may be advantageous. This study investigated whether inclusion of automated recognition of exudates and haemorrhages improves the detection of observable/referable diabetic retinopathy. Images from 1253 patients with observable/referable retinopathy and 6333 patients with non-referable retinopathy were obtained from three grading centres. All images were reference-graded, and automated disease/no disease assessments were made based on microaneurysm detection and combined microaneurysm, exudate and haemorrhage detection. Introduction of algorithms for exudates and haemorrhages resulted in a statistically significant increase in the sensitivity for detection of observable/referable retinopathy from 94.9% (95% CI 93.5 to 96.0) to 96.6% (95.4 to 97.4) without affecting manual grading workload. Automated detection of exudates and haemorrhages improved the detection of observable/referable retinopathy.

  16. Visual functions and disability in diabetic retinopathy patients

    OpenAIRE

    Shrestha, Gauri Shankar; Kaiti, Raju

    2013-01-01

    Purpose: This study was undertaken to find correlations between visual functions and visual disabilities in patients with diabetic retinopathy. Method: A cross-sectional study was carried out among 38 visually impaired diabetic retinopathy subjects at the Low Vision Clinic of B.P. Koirala Lions Centre for Ophthalmic Studies, Kathmandu. The subjects underwent assessment of distance and near visual acuity, objective and subjective refraction, contrast sensitivity, color vision, and central a...

  17. Photobiomodulation Mitigates Diabetes-Induced Retinopathy by Direct and Indirect Mechanisms: Evidence from Intervention Studies in Pigmented Mice.

    Directory of Open Access Journals (Sweden)

    Alexandra Saliba

    Full Text Available Daily application of far-red light from the onset of diabetes mitigated diabetes-induced abnormalities in retinas of albino rats. Here, we test the hypothesis that photobiomodulation (PBM is effective in diabetic, pigmented mice, even when delayed until weeks after onset of diabetes. Direct and indirect effects of PBM on the retina also were studied.Diabetes was induced in C57Bl/6J mice using streptozotocin. Some diabetics were exposed to PBM therapy (4 min/day; 670 nm daily. In one study, mice were diabetic for 4 weeks before initiation of PBM for an additional 10 weeks. Retinal oxidative stress, inflammation, and retinal function were measured. In some mice, heads were covered with a lead shield during PBM to prevent direct illumination of the eye, or animals were treated with an inhibitor of heme oxygenase-1. In a second study, PBM was initiated immediately after onset of diabetes, and administered daily for 2 months. These mice were examined using manganese-enhanced MRI to assess effects of PBM on transretinal calcium channel function in vivo.PBM intervention improved diabetes-induced changes in superoxide generation, leukostasis, expression of ICAM-1, and visual performance. PBM acted in part remotely from the retina because the beneficial effects were achieved even with the head shielded from the light therapy, and because leukocyte-mediated cytotoxicity of retinal endothelial cells was less in diabetics treated with PBM. SnPP+PBM significantly reduced iNOS expression compared to PBM alone, but significantly exacerbated leukostasis. In study 2, PBM largely mitigated diabetes-induced retinal calcium channel dysfunction in all retinal layers.PBM induces retinal protection against abnormalities induced by diabetes in pigmented animals, and even as an intervention. Beneficial effects on the retina likely are mediated by both direct and indirect mechanisms. PBM is a novel non-pharmacologic treatment strategy to inhibit early changes of diabetic

  18. Visible light induced photoelectrochemical biosensing based on oxygen-sensitive quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wenjing; Bao Lei [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Lei Jianping, E-mail: jpl@nju.edu.cn [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Tu Wenwen [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China); Ju Huangxian, E-mail: hxju@nju.edu.cn [State Key Laboratory of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing 210093 (China)

    2012-09-26

    Highlights: Black-Right-Pointing-Pointer The near-infrared QDs are synthesized in an aqueous solution. Black-Right-Pointing-Pointer QDs-based biosensor exhibits visible-light induced cathodic photocurrent. Black-Right-Pointing-Pointer The oxygen dependency of the photocurrent is verified. Black-Right-Pointing-Pointer A photoelectrochemical strategy is established by coupling with enzymatic reaction. Black-Right-Pointing-Pointer Photoelectrochemical sensor shows high upper detection limit, acceptable stability and accuracy. - Abstract: A visible light induced photoelectrochemical biosensing platform based on oxygen-sensitive near-infrared quantum dots (NIR QDs) was developed for detection of glucose. The NIR QDs were synthesized in an aqueous solution, and characterized with scanning electron microscopy and X-ray photoelectron spectroscopy. The as-prepared NIR QDs were employed to construct oxygen-sensitive photoelectrochemical biosensor on a fluorine-doped tin oxide (FTO) electrode. The oxygen dependency of the photocurrent was investigated at as-prepared electrode, which demonstrated the signal of photocurrent is suppressed with the decreasing of oxygen. Coupling with the consumption of oxygen during enzymatic reaction, a photoelectrochemical strategy was proposed for the detection of substrate. Using glucose oxidase (GOx) as a model enzyme, that is, GOx was covalently attached to the surface of CdTe QDs, the resulting biosensor showed the sensitive response to glucose. Under the irradiation of visible light of a wavelength at 505 nm, the proposed photoelectrochemical method could detect glucose ranging from 0.1 mM to 11 mM with a detection limit of 0.04 mM. The photoelectrochemical biosensor showed a good performance with high upper detection limit, acceptable stability and accuracy, providing an alternative method for monitoring biomolecules and extending the application of near-infrared QDs.

  19. Diabetic retinopathy - ocular complications of diabetesmellitus

    Institute of Scientific and Technical Information of China (English)

    Martin M Nentwich; Michael W Ulbig

    2015-01-01

    In industrialized nations diabetic retinopathy is the mostfrequent microvascular complication of diabetes mellitusand the most common cause of blindness in the workingagepopulation. In the next 15 years, the number ofpatients suffering from diabetes mellitus is expected toincrease significantly. By the year 2030, about 440 millionpeople in the age-group 20-79 years are estimated to besuffering from diabetes mellitus worldwide (prevalence7.7%), while in 2010 there were 285 million people withdiabetes mellitus (prevalence 6.4%). This accounts foran increase in patients with diabetes in industrialized nations by 20% and in developing countries by 69% until the year 2030. Due to the expected rise in diabetic patients, the need for ophthalmic care of patients (i.e. , exams and treatments) will also increase and represents a challenge for eye-care providers. Development of optimized screening programs, which respect available resources of the ophthalmic infrastructure, will become even more important. Main reasons for loss of vision in patients with diabetes mellitus are diabetic macular edema and proliferative diabetic retinopathy. Incidence or progression of these potentially blinding complications can be greatly reduced by adequate control of blood glucose and blood pressure levels. Additionally, regular ophthalmic exams are mandatory for detecting ocular complications and initiating treatments such as laser photocoagulation in case of clinical significant diabetic macular edema or early proliferative diabetic retinopathy. In this way, the risk of blindness can considerably be reduced. In advanced stages of diabetic retinopathy, pars-plana vitrectomy is performed to treat vitreous hemorrhage and tractional retinal detachment. In recent years, the advent of intravitreal medication has improved therapeutic options for patients with advanced diabetic macular edema.

  20. Retinopathy in youth with type 2 diabetes participating in the TODAY clinical trial

    Science.gov (United States)

    The objective of this study was to determine the prevalence of retinopathy in 517 youth with type 2 diabetes of 2–8 years duration enrolled in the TODAY study. Retinal photographs were graded centrally for retinopathy using established standards. Retinopathy was identified in 13.7% of subjects. Prev...

  1. Incidence, risk factors, and morphology in operating microscope light retinopathy

    International Nuclear Information System (INIS)

    Khwarg, S.G.; Linstone, F.A.; Daniels, S.A.; Isenberg, S.J.; Hanscom, T.A.; Geoghegan, M.; Straatsma, B.R.

    1987-01-01

    A review of 135 consecutive cataract operations identified ten cases (7.4%) of operating microscope light retinopathy. Ophthalmoscopically, these light retinopathy lesions appeared as a focal pigment epithelial change with varying degrees of pigment clumping in the center. Fluorescein angiography accentuated the lesion by demonstrating a sharply demarcated transmission defect, occasionally with multiple satellite lesions. The shape of the lesion matched the shape of the illuminating source of the particular operating microscope used during the surgery. The most significant risk factor associated with the production of these light retinopathy lesions was prolonged operating time. Mean total operating time for the ten patients with light retinopathy was 51 minutes longer than for those without (P less than .0001). Other significant associated factors were the presence of diabetes mellitus (P less than .03), younger age (P less than .05), and the use of hydrochlorothiazide (P less than .04)

  2. HYPERAUTOFLUORESCENT RING IN AUTOIMMUNE RETINOPATHY

    Science.gov (United States)

    LIMA, LUIZ H.; GREENBERG, JONATHAN P.; GREENSTEIN, VIVIENNE C.; SMITH, R. THEODORE; SALLUM, JULIANA M. F.; THIRKILL, CHARLES; YANNUZZI, LAWRENCE A.; TSANG, STEPHEN H.

    2015-01-01

    Purpose To report the presence of a hyperautofluorescent ring and corresponding spectral-domain optical coherence tomography (SD-OCT) features seen in patients with autoimmune retinopathy. Methods All eyes were evaluated by funduscopic examination, full-fleld electroretinography, fundus autofluorescence, and SD-OCT. Further confirmation of the diagnosis was obtained with immunoblot and immunohistochemistry testing of the patient’s serum. Humphrey visual fields and microperimetry were also performed. Results Funduscopic examination showed atrophic retinal pigment epithelium (RPE) associated with retinal artery narrowing but without pigment deposits. The scotopic and photopic full-field electroretinograms were nondetectable in three patients and showed a cone–rod pattern of dysfunction in one patient. Fundus autofluorescence revealed a hyperautofluorescent ring in the parafoveal region, and the corresponding SD-OCT demonstrated loss of the photoreceptor inner segment–outer segment junction with thinning of the outer nuclear layer from the region of the hyperautofluorescent ring toward the retinal periphery. The retinal layers were generally intact within the hyperautofluorescent ring, although the inner segment–outer segment junction was disrupted, and the outer nuclear layer and photoreceptor outer segment layer were thinned. Conclusion This case series revealed the structure of the hyperautofluorescent ring in autoimmune retinopathy using SD-OCT. Fundus autofluorescence and SD-OCT may aid in the diagnosis of autoimmune retinopathy and may serve as a tool to monitor its progression. PMID:22218149

  3. Agreement between photographic screening and hospital biomicroscopy grading of diabetic retinopathy and maculopathy.

    Science.gov (United States)

    Healy, Rachel; Sallam, Ahmed; Jones, Vanessa; Donachie, Paul H J; Scanlon, Peter H; Stratton, Irene M; Johnston, Robert L

    2014-01-01

    To examine the level of agreement and reasons for disagreement between grading of diabetic retinopathy and maculopathy using mydriatic digital photographs in a diabetic retinopathy screening service (DRSS) and hospital eye service (HES). English NHS Diabetic Eye Screening Programme grades for diabetic retinopathy prospectively recorded on a hospital electronic medical record were compared to the grades from the DRSS event that prompted referral. In cases of disagreement, images were reviewed. Data for 1,501 patients (3,002 eyes) referred between 2008 and 2011 were analyzed. The HES retinopathy grades were R0 (no retinopathy) in 341 eyes, R1 (background retinopathy) in 1,712 eyes, R2 (pre-proliferative retinopathy) in 821 eyes, and R3 (proliferative retinopathy) in 128 eyes. The DRSS grades were in agreement in 2,309 eyes (76.9%), recorded a lower grade in 227 eyes, and recorded a higher grade in 466 eyes. Agreement was substantial (κ = 0.65). The commonest cause for disagreement was overgrading of R1 as R2 by hospital clinicians. The HES maculopathy grades were M0 (no maculopathy) in 2,267 eyes and M1 (maculopathy) in 735 eyes. The DRSS were in agreement in 2,111 eyes (70.2%), recorded a lower grade in 106 eyes, and recorded a higher grade in 785 eyes. Agreement was fair (κ = 0.39). The commonest cause for disagreement was hospital clinicians missing fine exudates. This study establishes a benchmark standard for agreement between HES and DRSS grading. Review of DRSS and grading reports images for newly referred patients is likely to improve levels of agreement, particularly for diabetic retinopathy, and should be strongly encouraged.

  4. Digital tool for detecting diabetic retinopathy in retinography image using gabor transform

    Science.gov (United States)

    Morales, Y.; Nuñez, R.; Suarez, J.; Torres, C.

    2017-01-01

    Diabetic retinopathy is a chronic disease and is the leading cause of blindness in the population. The fundamental problem is that diabetic retinopathy is usually asymptomatic in its early stage and, in advanced stages, it becomes incurable, hence the importance of early detection. To detect diabetic retinopathy, the ophthalmologist examines the fundus by ophthalmoscopy, after sends the patient to get a Retinography. Sometimes, these retinography are not of good quality. This paper show the implementation of a digital tool that facilitates to ophthalmologist provide better patient diagnosis suffering from diabetic retinopathy, informing them that type of retinopathy has and to what degree of severity is find . This tool develops an algorithm in Matlab based on Gabor transform and in the application of digital filters to provide better and higher quality of retinography. The performance of algorithm has been compared with conventional methods obtaining resulting filtered images with better contrast and higher.

  5. Meal-induced changes in splanchnic blood flow and oxygen uptake in middle-aged healthy humans

    DEFF Research Database (Denmark)

    Madsen, Jan Lysgård; Søndergaard, SB; Møller, Søren

    2006-01-01

    OBJECTIVE: For decades, the determination of changes in splanchnic blood flow and oxygen uptake after a meal has been used in the management of patients with suspected chronic intestinal ischaemia. However, little is known about the normal meal-induced responses. The aim of the present study...... was therefore to measure the splanchnic blood flow and oxygen uptake before and after a standardized meal in a group of middle-aged normal volunteers. MATERIAL AND METHODS: Splanchnic blood flow and oxygen uptake were determined at baseline and after a 3600-kJ mixed meal in 8 healthy women (50-70 years) and 10...... healthy men (52-76 years). Splanchnic blood flow was measured during hepatic vein catheterization by indirect Fick principle with indocyanine green as the indicator. Splanchnic oxygen uptake was calculated from splanchnic blood flow and the arteriovenous oxygen difference. RESULTS: The meal induced...

  6. miR-23b-3p induces the cellular metabolic memory of high glucose in diabetic retinopathy through a SIRT1-dependent signalling pathway.

    Science.gov (United States)

    Zhao, Shuzhi; Li, Tao; Li, Jun; Lu, Qianyi; Han, Changjing; Wang, Na; Qiu, Qinghua; Cao, Hui; Xu, Xun; Chen, Haibing; Zheng, Zhi

    2016-03-01

    The mechanisms underlying the cellular metabolic memory induced by high glucose remain unclear. Here, we sought to determine the effects of microRNAs (miRNAs) on metabolic memory in diabetic retinopathy. The miRNA microarray was used to examine human retinal endothelial cells (HRECs) following exposure to normal glucose (N) or high glucose (H) for 1 week or transient H for 2 days followed by N for another 5 days (H→N). Levels of sirtuin 1 (SIRT1) and acetylated-nuclear factor κB (Ac-NF-κB) were examined following transfection with miR-23b-3p inhibitor or with SIRT1 small interfering (si)RNA in the H→N group, and the apoptotic HRECs were determined by flow cytometry. Retinal tissues from diabetic rats were similarly studied following intravitreal injection of miR-23b-3p inhibitor. Chromatin immunoprecipitation (ChIP) analysis was performed to detect binding of NF-κB p65 to the potential binding site of the miR-23b-27b-24-1 gene promoter in HRECs. High glucose increased miR-23b-3p expression, even after the return to normal glucose. Luciferase assays identified SIRT1 as a target mRNA of miR-23b-3p. Reduced miR-23b-3p expression inhibited Ac-NF-κB expression by rescuing SIRT1 expression and also relieved the effect of metabolic memory induced by high glucose in HRECs. The results were confirmed in the retina using a diabetic rat model of metabolic memory. High glucose facilitated the recruitment of NF-κB p65 and promoted transcription of the miR-23b-27b-24-1 gene, which can be suppressed by decreasing miR-23b-3p expression. These studies identify a novel mechanism whereby miR-23b-3p regulates high-glucose-induced cellular metabolic memory in diabetic retinopathy through a SIRT1-dependent signalling pathway.

  7. Radiation retinopathy after orbital irradiation for Graves' ophthalmopathy

    International Nuclear Information System (INIS)

    Kinyoun, J.L.; Kalina, R.E.; Brower, S.A.; Mills, R.P.; Johnson, R.H.

    1984-01-01

    Recent reports indicate that orbital irradiation for Graves' ophthalmopathy is sometimes beneficial, particularly for dysthyroid optic neuropathy, and is not associated with serious complications. We are aware, however, of four patients who were found to have radiation retinopathy after orbital irradiation for Grave's ophthalmopathy. All four patients have decreased central acuity, and three of the four are legally blind in one or both eyes. Computer reconstruction of the dosimetry, based on computed tomography and beam profiles, shows that errors in dosage calculations and radiotherapy technique probably account for the radiation retinopathy in three of the four patients. Radiotherapy for Graves' ophthalmopathy should be administered only by competent radiotherapists who are experienced in the treatment of this disease. Similar errors in dosage calculations and treatment techniques may account for other reports of radiation retinopathy after reportedly safe dosages

  8. Study on the changes of three renal functional parameters in patients with diabetic retinopathy

    International Nuclear Information System (INIS)

    Zhang Rong; Li Sumei; Zhang Li; Ye Shandong; Jin Chunyan; Ren An; Chen Ruoping; Chen Chao

    2009-01-01

    Objective: To study the relationship between development of diabetic retinopathy (DR) and changes of urinary albumin (UAlb),urine albumin-creatinine ratio (ACR), glomerular filtration rate (GFR) in patients with type 2 diabetes. Methods: Blood urea nitrogen (BUN), serum creatinine (SCr), 24 hours UAlb, ACR, radionuclide renal dynamic imaging (for GFR determination) and bilatera1 retinal photography were examined in 124 patients with type 2 diabetes. Of them 51 were without diabetic retinopathy(group A), 50 were with simple retinopathy(group B) and 23 were complicated with proliferate retinopathy(group C). Results: The UAlb, ACR in the patients with complicated diabetic retinopathy were significantly higher than those in the other two groups, while the GFR was significantly lower (P<0.05). Correlationship studies revealed that UAlb, ACR and GFR were independent risk factors of diabetic retinopathy. Conclusion: The severity of type 2 diabetes retinopathy is closely linked with the increase of UAlb, ACR and the decrease of GFR. Radionuclide renal dynamic imaging is helpful for the diagnosis of early stage of diabetic nephropathy (DN). (authors)

  9. Strain-induced oxygen vacancies in ultrathin epitaxial CaMnO3 films

    Science.gov (United States)

    Chandrasena, Ravini; Yang, Weibing; Lei, Qingyu; Delgado-Jaime, Mario; de Groot, Frank; Arenholz, Elke; Kobayashi, Keisuke; Aschauer, Ulrich; Spaldin, Nicola; Xi, Xiaoxing; Gray, Alexander

    Dynamic control of strain-induced ionic defects in transition-metal oxides is considered to be an exciting new avenue towards creating materials with novel electronic, magnetic and structural properties. Here we use atomic layer-by-layer laser molecular beam epitaxy to synthesize high-quality ultrathin single-crystalline CaMnO3 films with systematically varying coherent tensile strain. We then utilize a combination of high-resolution soft x-ray absorption spectroscopy and bulk-sensitive hard x-ray photoemission spectroscopy in conjunction with first-principles theory and core-hole multiplet calculations to establish a direct link between the coherent in-plane strain and the oxygen-vacancy content. We show that the oxygen vacancies are highly mobile, which necessitates an in-situ-grown capping layer in order to preserve the original strain-induced oxygen-vacancy content. Our findings open the door for designing and controlling new ionically active properties in strongly-correlated transition-metal oxides.

  10. [Buffering capacity of the vitreous body in aggressive posterior retinopathy of prematurity].

    Science.gov (United States)

    Amkhanitskaia, L I; Sidorenko, E I; Nikolaeva, G V; Kuznetsova, Iu D

    2014-01-01

    To investigate the role of vitreous body changes in the pathogenesis of aggressive posterior retinopathy of prematurity. The study included 60 children with stage 4-5 retinopathy of prematurity demonstrating either classical or aggressive posterior form of progression. In all cases vitreous samples for laboratory testing were taken during surgery. The study showed that aggressive posterior retinopathy of prematurity is associated with more significant metabolic changes in comparison with classical form of the disease. The degree of biochemical imbalance of the vitreous appeared directly related to the stage of the disease, which was determined by the type and extent of retinal detachment. Volcano-shaped retinal detachment with intensive exudation within the posterior eye segment is considered the most severe variant of aggressive posterior retinopathy of prematurity. Aggressive posterior retinopathy of prematurity is characterized by substantial disturbance of metabolism of the vitreous body, which contributes to exudation and proliferation, thus aggravating the course of the disease and worsening the prognosis.

  11. Awareness of diabetic retinopathy among patients with type 2 diabetes mellitus in Jordan.

    Science.gov (United States)

    Bakkar, May M; Haddad, Mera F; Gammoh, Yazan S

    2017-01-01

    Increasing the level of awareness of diabetic retinopathy among individuals with type 2 diabetes mellitus is considered an important factor for early diagnosis and management of diabetic retinopathy. The aim of this study was to evaluate awareness of diabetic retinopathy among a sample of type 2 diabetes mellitus patients in Jordan. The study period was from August to December 2015. The sample was selected randomly from patients with type 2 diabetes mellitus from the general population in three main cities of Jordan (Amman, Irbid, and Zarqa). A questionnaire was distributed to 237 participants with diabetes to assess their awareness and knowledge of diabetes and diabetic retinopathy. The questionnaire included questions to assess awareness about diabetic retinopathy, sources of knowledge about the disease, and patients' knowledge and compliance with available treatments and routine eye examinations. Patients were also questioned about the barriers that may interfere with early eye examination. A total of 237 participants (107 [45.1%] females and 130 [54.9%] males) with type 2 diabetes were interviewed. Mean age±SD for the study population was 54.51±10.28 years. Of the study population, 88.2% were aware that diabetes can affect the eyes and 81% reported that diabetic retinopathy can lead to blindness. Higher level of patients' awareness of diabetic retinopathy was related to higher level of formal education ( p diabetic retinopathy as reported by 47.3% patients was general practitioners. Patients' compliance with diabetes management was relatively high; however, their compliance with routine retinal assessment was poor, with only a total of 29.5% of participants having had an eye examination in the previous year. Awareness of the nature and consequences of diabetic retinopathy among patients with diabetes in Jordan is relatively high. However, patients' motivation to undergo retinal assessment was poor in the sample, thus hindering early diagnosis and management.

  12. Radiation retinopathy as an experimental model for ischemic proliferative retinopathy and rubeosis iridis

    International Nuclear Information System (INIS)

    Irvine, A.R.; Wood, I.S.

    1987-01-01

    We produced radiation retinopathy in capuchin monkeys and studied them with fluorescein angiography and light and electron microscopy. The animals were followed up from ten days to 3 1/2 years after radiation in order to determine whether this could provide an experimental model for other chronic ischemic-proliferative retinopathies, such as diabetes. The first change detected after radiation was the focal loss of capillary endothelial cells and pericytes. As the areas of acellular capillaries became confluent, cotton-wool spots became visible ophthalmoscopically. These increased in number and then faded away, leaving large areas of retinal capillary perfusion. Histologic studies showed occlusion first of the deeper, smaller retinal vessels and then gradually of the larger vessels. Intraretinal neovascularization as well as apparent recanalization then developed, but no new vessels extended through the internal limiting lamina into the vitreous. Rubeosis iridis with neovascular glaucoma developed 2 1/2 to 3 1/2 years postirradiation, and vitreous aspirate demonstrated a high level of angiogenic factor

  13. Neuroprotective Effect of Hydroxytyrosol in Experimental Diabetic Retinopathy: Relationship with Cardiovascular Biomarkers.

    Science.gov (United States)

    González-Correa, José Antonio; Rodríguez-Pérez, María Dolores; Márquez-Estrada, Lucía; López-Villodres, Juan Antonio; Reyes, José Julio; Rodriguez-Gutierrez, Guillermo; Fernández-Bolaños, Juan; De La Cruz, José Pedro

    2018-01-24

    The aim of the study was to test the neuroprotective effect of hydroxytyrosol (HT) on experimental diabetic retinopathy. Animals were divided in four groups: (1) control nondiabetic rats, (2) streptozotocin-diabetic rats (DR), (3) DR treated with 1 mg/kg/day p.o. HT, and (4) DR treated with 5 mg/kg/day p.o. HT. Treatment with HT was started 7 days before inducing diabetes and was maintained for 2 months. In the DR group, total area occupied by extracellular matrix was increased, area occupied by retinal cells was decreased; both returned to near-control values in DR rats treated with HT. The number of retinal ganglion cells in DR was significantly lower (44%) than in the control group, and this decrease was smaller after HT treatment (34% and 9.1%). Linear regression analysis showed that prostacyclin, platelet aggregation, peroxynitrites, and the dose of 5 mg/kg/day HT significantly influenced retinal ganglion cell count. In conclusion, HT exerted a neuroprotective effect on diabetic retinopathy, and this effect correlated significantly with changes in some cardiovascular biomarkers.

  14. Retinal Oximetry and Vessel Diameter Measurements With a Commercially Available Scanning Laser Ophthalmoscope in Diabetic Retinopathy.

    Science.gov (United States)

    Blair, Norman P; Wanek, Justin; Felder, Anthony E; Joslin, Charlotte E; Kresovich, Jacob K; Lim, Jennifer I; Chau, Felix Y; Leiderman, Yannek; Shahidi, Mahnaz

    2017-10-01

    To test the hypothesis that retinal vascular diameter and hemoglobin oxygen saturation alterations, according to stages of diabetic retinopathy (DR), are discernible with a commercially available scanning laser ophthalmoscope (SLO). One hundred eighty-one subjects with no diabetes (No DM), diabetes with no DR (No DR), nonproliferative DR (NPDR), or proliferative DR (PDR, all had photocoagulation) underwent imaging with an SLO with dual lasers (532 nm and 633 nm). Customized image analysis software determined the diameters of retinal arteries and veins (DA and DV) and central retinal artery and vein equivalents (CRAE and CRVE). Oxygen saturations of hemoglobin in arteries and veins (SO2A and SO2V) were estimated from optical densities of vessels on images at the two wavelengths. Statistical models were generated by adjusting for effects of sex, race, age, eye, and fundus pigmentation. DA, CRAE, and CRVE were reduced in PDR compared to No DM (P ≤ 0.03). DV and CRVE were similar between No DM and No DR, but they were higher in NPDR than No DR (P ≤ 0.01). Effect of stage of disease on SO2A differed by race, being increased relative to No DM in NPDR and PDR in Hispanic participants only (P ≤ 0.02). Relative to No DM, SO2V was increased in NPDR and PDR (P ≤ 0.05). Alterations in retinal vascular diameters and SO2 by diabetic retinopathy stage can be detected with a widely available SLO, and covariates such as race can influence the results.

  15. The relationship of the subtypes of preterm birth with retinopathy of prematurity.

    Science.gov (United States)

    Lynch, Anne M; Wagner, Brandie D; Hodges, Jennifer K; Thevarajah, Tamara S; McCourt, Emily A; Cerda, Ashlee M; Mandava, Naresh; Gibbs, Ronald S; Palestine, Alan G

    2017-09-01

    Retinopathy of prematurity is an adverse outcome of preterm birth and is a leading cause of childhood blindness. The relationship between the subtypes of preterm birth with retinopathy of prematurity is understudied. To investigate whether there is a difference in the incidence of type 1 or type 2 retinopathy of prematurity in infants with preterm birth resulting from spontaneous preterm labor, a medical indication of preterm birth, or preterm premature rupture of the membranes. A retrospective cohort study was conducted of 827 infants screened for retinopathy of prematurity who were delivered at a single tertiary care center in Colorado. All infants fulfilled the American Academy of Pediatrics 2013 screening criteria for retinopathy of prematurity defined as "infants with a birth weight of ≤1500 g or gestational age of 30 weeks or less (as defined by the attending neonatologist) and selected infants with a birth weight between 1500 and 2000 g or gestational age of >30 weeks with an unstable clinical course, including those requiring cardiorespiratory support and who are believed by their attending pediatrician or neonatologist to be at high risk for retinopathy of prematurity." Two independent reviewers masked to retinopathy of prematurity outcomes determined whether preterm birth resulted from spontaneous preterm labor, medical indication of preterm birth, or preterm premature rupture of the membranes. Discrepancies were resolved by a third reviewer. Data were analyzed with univariate and multivariable logistic regression. In our cohort, the frequency of preterm birth resulting from spontaneous preterm labor, medical indication of preterm birth, or preterm premature rupture of the membranes was 34%, 40%, and 26%, respectively. The mean gestational age (weeks, days) ± SD (range) in the cohort and across the preterm birth subtypes was as follows: entire cohort, 28 weeks, 6 days ± 2 weeks, 3 days (23 weeks, 3 days - 36 weeks, 4 days); spontaneous preterm labor

  16. Macrophage Metalloelastase (MMP-12) Deficiency Mitigates Retinal Inflammation and Pathological Angiogenesis in Ischemic Retinopathy

    Science.gov (United States)

    Li, Jingming; Wang, Joshua J.; Peng, Qisheng; Chen, Chen; Humphrey, Mary Beth; Heinecke, Jay; Zhang, Sarah X.

    2012-01-01

    Pathological angiogenesis is a major cause of vision loss in ischemic and inflammatory retinal diseases. Recent evidence implicates macrophage metalloelastase (MMP-12), a macrophage-derived elastinolytic protease in inflammation, tissue remodeling and angiogenesis. However, little is known about the role of MMP-12 in retinal pathophysiology. The present study aims to explore the enzyme’s contributions to retinal angiogenesis in oxygen-induced retinopathy (OIR) using MMP-12 knockout (KO) mice. We find that MMP-12 expression was upregulated in OIR, accompanied by elevated macrophage infiltration and increased inflammatory markers. Compared to wildtype mice, MMP-12 KO mice had decreased levels of adhesion molecule and inflammatory cytokines and reduced vascular leakage in OIR. Concomitantly, these mice had markedly reduced macrophage content in the retina with impaired macrophage migratory capacity. Significantly, loss of MMP-12 attenuated retinal capillary dropout in early OIR and mitigated pathological retinal neovascularization (NV). Similar results were observed in the study using MMP408, a pharmacological inhibitor of MMP-12. Intriguingly, in contrast to reducing pathological angiogenesis, lack of MMP-12 accelerated revascularization of avascular retina in OIR. Taken together, we conclude that MMP-12 is a key regulator of macrophage infiltration and inflammation, contributing to retinal vascular dysfunction and pathological angiogenesis. PMID:23285156

  17. Pattern of diabetic retinopathy in Kano, Nigeria | Lawan | Annals of ...

    African Journals Online (AJOL)

    Pattern of diabetic retinopathy in Kano, Nigeria. ... Background: The aim of the study is to determine the pattern of retinopathy seen in diabetic patients attending the outpatient clinic in Aminu Kano Teaching Hospital, Kano, ... A screening program needs to be developed to facilitate early detection and prompt treatment.

  18. Rates of progression in diabetic retinopathy during different time periods: a systematic review and meta-analysis

    DEFF Research Database (Denmark)

    Wong, Tien Y; Mwamburi, Mkaya; Klein, Ronald

    2009-01-01

    This meta-analysis reviews rates of progression of diabetic retinopathy to proliferative diabetic retinopathy (PDR) and/or severe visual loss (SVL) and temporal trends.......This meta-analysis reviews rates of progression of diabetic retinopathy to proliferative diabetic retinopathy (PDR) and/or severe visual loss (SVL) and temporal trends....

  19. Treatment of threshold retinopathy of prematurity

    Directory of Open Access Journals (Sweden)

    Deshpande Dhanashree

    1998-01-01

    Full Text Available This report deals with our experience in the management of threshold retinopathy of prematurity (ROP. A total of 45 eyes of 23 infants were subjected to treatment of threshold ROP. 26.1% of these infants had a birth weight of >l,500 gm. The preferred modality of treatment was laser indirect photocoagulation, which was facilitated by scleral depression. Cryopexy was done in cases with nondilating pupils or medial haze and was always under general anaesthesia. Retreatment with either modality was needed in 42.2% eyes; in this the skip areas were covered. Total regression of diseases was achieved in 91.1% eyes with no sequelae. All the 4 eyes that progressed to stage 5 despite treatment had zone 1 disease. Major treatment-induced complications did not occur in this series. This study underscores the importance of routine screening of infants upto 2,000 gm birth weight for ROP and the excellent response that is achieved with laser photocoagulation in inducing regression of threshold ROP. Laser is the preferred method of treatment in view of the absence of treatment-related morbidity to the premature infants.

  20. Screening for retinopathy of prematurity and treatment outcome in a tertiary hospital in Hong Kong.

    Science.gov (United States)

    Iu, L Pl; Lai, C Hy; Fan, M Cy; Wong, I Yh; Lai, J Sm

    2017-02-01

    Studies on the prevalence and severity of retinopathy of prematurity in the local population are scarce. This study aimed to evaluate the prevalence, screening, and treatment outcome of retinopathy of prematurity in a tertiary hospital in Hong Kong. This cross-sectional study with internal comparison was conducted at Queen Mary Hospital, Hong Kong. The study evaluated 89 premature infants who were born at the hospital and were screened for retinopathy of prematurity, in accordance with the 2008 British Guidelines, between January 2013 and December 2013. The prevalences of retinopathy of prematurity and severe retinopathy requiring treatment were studied. The mean (± standard deviation) gestational age at birth was 30 +2 weeks ± 16.5 days (range, 24 +1 to 35 +5 weeks). The mean birth weight was 1285 g ± 328 g (range, 580 g to 2030 g). A total of 15 (16.9%) infants developed retinopathy of prematurity and three (3.4%) required treatment. In a subgroup analysis of extremely-low-birth-weight infants of prematurity and 17.6% required treatment. Multivariate logistic regression analysis suggested low birth weight and patent ductus arteriosus were significantly associated with development of retinopathy of prematurity (Pprematurity, all regressed successfully after one laser treatment. Retinopathy of prematurity is a significant problem among premature infants in Hong Kong, especially those with extremely low birth weight. Our screening service for retinopathy of prematurity was satisfactory and treatment results were good. Strict adherence to international screening guidelines and vigilance in infants at risk are key to successful management of retinopathy of prematurity.

  1. PLVAP in diabetic retinopathy: A gatekeeper of angiogenesis and vascular permeability

    NARCIS (Netherlands)

    Wiśniewska-Kruk, J.

    2014-01-01

    Nowadays, approximately 4 million people worldwide experience blindness or severe vision loss caused by diabetic retinopathy. Diabetic retinopathy is a multifactorial disease that can progress from minor changes in vascular permeability, into a proliferative retinal disorder. The increasing

  2. New Ways to Detect Pediatric Sickle Cell Retinopathy: A Comprehensive Review.

    Science.gov (United States)

    Pahl, Daniel A; Green, Nancy S; Bhatia, Monica; Chen, Royce W S

    2017-11-01

    Sickle retinopathy reflects disease-related vascular injury of the eye, which can potentially result in visual loss from vitreous hemorrhage or retinal detachment. Here we review sickle retinopathy among children with sickle cell disease, describe the epidemiology, pediatric risk factors, pathophysiology, ocular findings, and treatment. Newer, more sensitive ophthalmological imaging modalities are available for retinal imaging, including ultra-widefield fluorescein angiography, spectral-domain optical coherence tomography, and optical coherence tomography angiography. Optical coherence tomography angiography provides a noninvasive view of retinal vascular layers that could previously not be imaged and can be quantified for comparative or prospective analyses. Ultra-widefield fluorescein angiography provides a more comprehensive view of the peripheral retina than traditional imaging techniques. Screening for retinopathy by standard fundoscopic imaging modalities detects a prevalence of approximately 10%. In contrast, these more sensitive methods allow for more sensitive examination that includes the retina perimeter where sickle retinopathy is often first detectable. Use of these new imaging modalities may detect a higher prevalence of early sickle pathology among children than has previously been reported. Earlier detection may help in better understanding the pathogenesis of sickle retinopathy and guide future screening and treatment paradigms.

  3. Petaloid-pattern pigmentary retinopathy: a novel case report.

    Science.gov (United States)

    Padhi, Tapas Ranjan; Jalali, Subhadra; Panda, Krushna Gopal; Mukherjee, Sujoy; Mohan, Neha; Agroiya, Pushpalata; Das, Taraprasad

    2014-10-01

    We report the case of a 6-year-old girl with an unusual petaloid-pattern pigmentary retinopathy associated with nyctalopia and reduction of vision which had been invariably static over the past 5 years. We performed a comprehensive ophthalmic examination including fundoscopy, autofluorescent imaging, electroretinography and optical coherence tomography. There were diffuse retinal pigment epithelium (RPE) washout areas with blotches of pigment distributed in the pattern of a petal with marked chorioretinal atrophy and scar at the fovea. The arterial caliber was normal. Investigations ruled out intrauterine and neonatal infection. Systemically, she was healthy with normal intellect but with 3-month delayed milestones of development. She had used valproic acid for seizure disorder (without any organic central nervous system lesion) from 2-5 years of age. Electroretinography showed extinguished scotopic responses with slight reduction in cone responses. Optical coherence tomography showed a scar with attenuated RPE-choriocapillary complex at the macula. Her clinical profile did not fully match with any previously described pigmentary retinopathies except rod-cone dystrophy and choroidal dystrophy to a certain extent. The pigmentary retinopathy reported here is a combination of a petaloid pattern of pigmentary disturbance, stationary reduction of vision, nyctalopia, normal intellect and marginal delayed milestones. In the absence of such a description in the literature we named this disorder as petaloid-pattern pigmentary retinopathy.

  4. The influence of background diabetic retinopathy in the second eye on rates of progression of diabetic retinopathy between 2005 and 2010.

    Science.gov (United States)

    Scanlon, Peter H; Stratton, Irene M; Histed, Mark; Chave, Steve J; Aldington, Stephen J

    2013-08-01

    The Gloucestershire Diabetic Eye Screening Programme offers annual digital photographic screening for diabetic retinopathy to a countywide population of people with diabetes. This study was designed to investigate progression of diabetic retinopathy in this programme of the English NHS Diabetic Eye Screening Programme. Mydriatic digital retinal photographs of people with diabetes screened on at least 2 occasions between 2005 and 2010 were graded and included in this study if the classification at first screening was no DR (R0), background DR in one (R1a) or both eyes (R1b). Times to detection of referable diabetic retinopathy (RDR) comprising maculopathy (M1), preproliferative (R2) or proliferative retinopathy (R3) were analysed using survival models. Data were available on 19 044 patients, 56% men, age at screening 66 (57-74) years (median, 25th, 75th centile). A total of 8.3% of those with R1a and 28.2% of those with R1b progressed to any RDR, hazard ratios 2.9 [2.5-3.3] and 11.3 [10.0-12.8]. Similarly 7.1% and 0.11% of those with R1a progressed to M1 and R3, hazard ratios 2.7 [2.3-3.2] and 1.6 [0.5-5.0], compared to 21.8% and 1.07% of those with R1b, hazard ratio 9.1 [7.8-10.4] and 15.0 [7.1-31.5]. The risk of progression is significantly higher for those with background DR in both eyes than those with background retinopathy in only one or in neither eye. © 2013 The Authors Acta Ophthalmologica © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by Blackwell Publishing Ltd.

  5. Hyperbaric oxygen as sole treatment for severe radiation - induced haemorrhagic cystitis

    Energy Technology Data Exchange (ETDEWEB)

    Dellis, Athanasios, E-mail: aedellis@gmail.com [Department of Surgery, National and Kapodistrian University of Athens, Aretaieion Academic Hospital, Athens (Greece); Papatsoris, Athanasios; Deliveliotis, Charalambos; Skolarikos, Andreas [Department of Urology, University of Athens, Sismanoglio General Hospital, Athens (Greece); Kalentzos, Vasileios [Department of Diving and Hyperbaric Oxygen, Naval and Veterans Hospital, Athens (Greece)

    2017-05-15

    Purpose: To examine the safety and efficacy of hyperbaric oxygen as the primary and sole treatment for severe radiation-induced haemorrhagic cystitis. Materials and methods: Hyperbaric oxygen was prospectively applied as primary treatment in 38 patients with severe radiation cystitis. Our primary endpoint was the incidence of complete and partial response to treatment, while the secondary endpoints included the duration of response, the correlation of treatment success-rate to the interval between the onset of haematuria and initiation of therapy, blood transfusion need and total radiation dose, the number of sessions to success, the avoidance of surgery and the overall survival. Results: All patients completed therapy without complications with a mean follow-up of 29.33 months. Median number of sessions needed was 33. Complete and partial response rate was 86.8% and 13.2%, respectively. All 33 patients with complete response received therapy within 6 months of the haematuria onset. One patient needed cystectomy, while 33 patients were alive at the end of follow-up. Conclusions: Our study suggests the early primary use of hyperbaric oxygen for radiation-induced severe cystitis as an effective and safe treatment option. (author)

  6. Progression of diabetic retinopathy during pregnancy in women with type 2 diabetes

    DEFF Research Database (Denmark)

    Rasmussen, K.L.; Laugesen, C.S.; Nielsen, Lene Ringholm

    2010-01-01

    We studied the progression of diabetic retinopathy during pregnancy in women with type 2 diabetes.......We studied the progression of diabetic retinopathy during pregnancy in women with type 2 diabetes....

  7. Evaluation of VEGF gene polymorphisms and proliferative diabetic retinopathy in Mexican population.

    Science.gov (United States)

    Gonzalez-Salinas, Roberto; Garcia-Gutierrez, Maria C; Garcia-Aguirre, Gerardo; Morales-Canton, Virgilio; Velez-Montoya, Raul; Soberon-Ventura, Vidal R; Gonzalez, Victoria; Lechuga, Rodrigo; Garcia-Solis, Pablo; Garcia-Gutierrez, David G; Garcia-Solis, Marco Vinicio; Saenz de Viteri, Manuel; Solis-S, Juan C

    2017-01-01

    To assess if the included vascular endothelial growth factor (VEGF) polymorphisms rs3025035, rs3025021 and rs2010963 are associated to proliferative retinopathy in a Mexican population with type 2 diabetes mellitus (T2DM). A case-control study was conducted in adult individuals with T2DM associated to proliferative retinopathy or non-proliferative retinopathy from Oct. 2014 to Jun. 2015 from the Retina Department of the Asociation to Prevent Blindness in Mexico. The selected patients were adults with a diagnosis of T2DM ≥5y. All subjects had a comprehensive ocular examination and the classification of the retinopathy severity was made considering the Early Treatment Diabetic Retinopathy Study (ETDRS) standardization protocols. Genomic DNA was extracted from whole fresh blood. All samples were genotyped by qPCR for selected VEGF polymorphisms. Hardy-Weinberg equilibrium was calculated by comparing Chi-square values between the expected and the observed values for genotype counts. In total 142 individuals were enrolled, 71 individuals with T2DM and associated proliferative retinopathy and 71 individuals with non-proliferative retinopathy. One-sided Fisher's exact test was performed for rs3025021 [OR (95% CI)=0.44(0.08-2.2); P =0.25] and rs2010963 [OR (95% CI)=0.63(0.25-1.6); P =0.23]. The minor allelic frequencies obtained were 26% for rs3025021, 10% for rs3025035 and 61% for rs2010963. The pairwise linkage disequilibrium between the three SNP was assessed, and was as follows: rs3025021 vs rs3025035: D'=1.0, r 2 =0.1043, P ≤0.0001; rs3025021 vs rs2010963: D'=0.442, r 2 =0.0446, P =0.149; rs3025035 vs rs2010963: D'=0.505, r 2 =0.0214, P =0.142. This is the first analysis involving VEGF polymorphisms and proliferative diabetic retinopathy in a Mexican population. A major finding of the present study is that none of the polymorphisms studied was significantly associated with proliferative retinopathy. Based on these results, we can infer that different populations

  8. Diabetic Retinopathy: Vascular and Inflammatory Disease

    Science.gov (United States)

    Semeraro, F.; Cancarini, A.; dell'Omo, R.; Rezzola, S.; Romano, M. R.; Costagliola, C.

    2015-01-01

    Diabetic retinopathy (DR) is the leading cause of visual impairment in the working-age population of the Western world. The pathogenesis of DR is complex and several vascular, inflammatory, and neuronal mechanisms are involved. Inflammation mediates structural and molecular alterations associated with DR. However, the molecular mechanisms underlying the inflammatory pathways associated with DR are not completely characterized. Previous studies indicate that tissue hypoxia and dysregulation of immune responses associated with diabetes mellitus can induce increased expression of numerous vitreous mediators responsible for DR development. Thus, analysis of vitreous humor obtained from diabetic patients has made it possible to identify some of the mediators (cytokines, chemokines, and other factors) responsible for DR pathogenesis. Further studies are needed to better understand the relationship between inflammation and DR. Herein the main vitreous-related factors triggering the occurrence of retinal complication in diabetes are highlighted. PMID:26137497

  9. Monitoring of Diabetic Retinopathy in relation to Bariatric Surgery

    DEFF Research Database (Denmark)

    Brynskov, Troels; Laugesen, Caroline Schmidt; Svenningsen, Annette Lykke

    2016-01-01

    BACKGROUND: To investigate the need for closer perioperative monitoring of diabetic retinopathy in patients with type 2 diabetes undergoing bariatric surgery. METHODS: Prospective observational clinical study of 56 patients with type 2 diabetes undergoing bariatric surgery. The patients were...... examined with 7-field fundus images and optical coherence tomography scans 2 weeks before and 1, 3, 6 and 12 months after bariatric surgery. Worsening was defined as a two-step change in the Wisconsin Epidemiologic Study of Diabetic Retinopathy scale or appearance or worsening of macular edema......%) of the 32 patients without preoperative diabetic retinopathy had a transient worsening at 6 months. No patients developed macular edema, but the whole cohort had a minor increase in center point foveal thickness that peaked 6 months postoperatively. The patients were required to have good glucose control...

  10. Comparison between Early Treatment Diabetic Retinopathy Study 7-field retinal photos and non-mydriatic, mydriatic and mydriatic steered widefield scanning laser ophthalmoscopy for assessment of diabetic retinopathy

    DEFF Research Database (Denmark)

    Rasmussen, Malin L; Broe, Rebecca; Frydkjaer-Olsen, Ulrik

    2015-01-01

    AIMS: To compare non-mydriatic, mydriatic and steered mydriatic widefield retinal images with mydriatic 7-field Early Treatment Diabetic Retinopathy Study (ETDRS)-standards in grading diabetic retinopathy (DR). METHODS: We examined 95 patients (190 eyes) with type 1 diabetes. A non...

  11. Association between diabetic retinopathy and subclinical atherosclerosis in China: Results from a community-based study.

    Science.gov (United States)

    Liu, Yu; Teng, Xiangyu; Zhang, Wei; Zhang, Ruifeng; Liu, Wei

    2015-09-01

    To evaluate the association of diabetic retinopathy with subclinical atherosclerosis in middle-aged and elderly Chinese with type 2 diabetes. A cross-sectional community-based study was performed among 1607 patients aged 40 years or older in Shanghai. Non-mydriatic digital fundus photography examination was used in diabetic retinopathy detection. Presence of elevated carotid intima-media thickness or carotid plaque was defined as subclinical atherosclerosis. The prevalence of diabetic retinopathy was 15.1% in total patients. Patients with diabetic retinopathy were more likely to have elevated carotid intima-media thickness, carotid plaque and subclinical atherosclerosis than those without diabetic retinopathy (37.9% vs 30.7%, 57.6% vs 49.6% and 64.6% vs 57.1%, respectively). The presence of diabetic retinopathy was significantly associated with increased odds of subclinical atherosclerosis (odds ratio = 1.93, 95% confidence interval = 1.03-3.60) after full adjustments. The presence of diabetic retinopathy was significantly associated with subclinical atherosclerosis in middle-aged and elderly patients with type 2 diabetics in China. © The Author(s) 2015.

  12. Relationship between retinal vessel diameters and retinopathy in the Inter99 Eye Study

    DEFF Research Database (Denmark)

    Drobnjak, Dragana; Munch, Inger Christine; Glümer, Charlotte

    2017-01-01

    PURPOSE: To examine the association between retinal vessel diameters and retinopathy in participants with and without type 2 diabetes in a Danish population-based cohort. METHODS: The study included 878 persons aged 30 to 60 years from the Inter99 Eye Study. Retinopathy was defined as a presence...... was 6.3 µm (CI 95%: 1.0 to 11.6, p = 0.020) wider and CRVE was 7.9 µm (CI 95%: 0.7 to 15.2, p = 0.030) wider in those with retinopathy compared to those without retinopathy, after adjusting for age, gender, HbA1c, blood pressure, smoking, serum total and HDL cholesterol. In all participants, CRAE.......001), and decreased with higher HDL cholesterol (p gender was associated with wider CRVE (p = 0.029). CONCLUSIONS: Wider retinal vessel diameters were associated with the presence of retinopathy in participants with diabetes, but not in participants without diabetes...

  13. Computer-Assisted Digital Image Analysis of Plus Disease in Retinopathy of Prematurity.

    Science.gov (United States)

    Kemp, Pavlina S; VanderVeen, Deborah K

    2016-01-01

    The objective of this study is to review the current state and role of computer-assisted analysis in diagnosis of plus disease in retinopathy of prematurity. Diagnosis and documentation of retinopathy of prematurity are increasingly being supplemented by digital imaging. The incorporation of computer-aided techniques has the potential to add valuable information and standardization regarding the presence of plus disease, an important criterion in deciding the necessity of treatment of vision-threatening retinopathy of prematurity. A review of literature found that several techniques have been published examining the process and role of computer aided analysis of plus disease in retinopathy of prematurity. These techniques use semiautomated image analysis techniques to evaluate retinal vascular dilation and tortuosity, using calculated parameters to evaluate presence or absence of plus disease. These values are then compared with expert consensus. The study concludes that computer-aided image analysis has the potential to use quantitative and objective criteria to act as a supplemental tool in evaluating for plus disease in the setting of retinopathy of prematurity.

  14. PPAR Agonists: Potential as Therapeutics for Neovascular Retinopathies

    Directory of Open Access Journals (Sweden)

    Harrihar A. Pershadsingh

    2008-01-01

    Full Text Available The angiogenic, neovascular proliferative retinopathies, proliferative diabetic retinopathy (PDR, and age-dependent macular degeneration (AMD complicated by choroidal neovascularization (CNV, also termed exudative or “wet” AMD, are common causes of blindness. The antidiabetic thiazolidinediones (TZDs, rosiglitazone, and troglitazone are PPAR agonists with demonstrable antiproliferative, and anti-inflammatory effects, in vivo, were shown to ameliorate PDR and CNV in rodent models, implying the potential efficacy of TZDs for treating proliferative retinopathies in humans. Activation of the angiotensin II type 1 receptor (AT1-R propagates proinflammatory and proliferative pathogenic determinants underlying PDR and CNV. The antihypertensive dual AT1-R blocker (ARB, telmisartan, recently was shown to activate PPAR and improve glucose and lipid metabolism and to clinically improve PDR and CNV in rodent models. Therefore, the TZDs and telmisartan, clinically approved antidiabetic and antihypertensive drugs, respectively, may be efficacious for treating and attenuating PDR and CNV humans. Clinical trials are needed to test these possibilities.

  15. Automated detection of exudates for diabetic retinopathy screening

    International Nuclear Information System (INIS)

    Fleming, Alan D; Philip, Sam; Goatman, Keith A; Williams, Graeme J; Olson, John A; Sharp, Peter F

    2007-01-01

    Automated image analysis is being widely sought to reduce the workload required for grading images resulting from diabetic retinopathy screening programmes. The recognition of exudates in retinal images is an important goal for automated analysis since these are one of the indicators that the disease has progressed to a stage requiring referral to an ophthalmologist. Candidate exudates were detected using a multi-scale morphological process. Based on local properties, the likelihoods of a candidate being a member of classes exudate, drusen or background were determined. This leads to a likelihood of the image containing exudates which can be thresholded to create a binary decision. Compared to a clinical reference standard, images containing exudates were detected with sensitivity 95.0% and specificity 84.6% in a test set of 13 219 images of which 300 contained exudates. Depending on requirements, this method could form part of an automated system to detect images showing either any diabetic retinopathy or referable diabetic retinopathy

  16. Automated detection of exudates for diabetic retinopathy screening

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Alan D [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Philip, Sam [Diabetes Retinal Screening Service, David Anderson Building, Foresterhill Road, Aberdeen, AB25 2ZP (United Kingdom); Goatman, Keith A [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Williams, Graeme J [Diabetes Retinal Screening Service, David Anderson Building, Foresterhill Road, Aberdeen, AB25 2ZP (United Kingdom); Olson, John A [Diabetes Retinal Screening Service, David Anderson Building, Foresterhill Road, Aberdeen, AB25 2ZP (United Kingdom); Sharp, Peter F [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom)

    2007-12-21

    Automated image analysis is being widely sought to reduce the workload required for grading images resulting from diabetic retinopathy screening programmes. The recognition of exudates in retinal images is an important goal for automated analysis since these are one of the indicators that the disease has progressed to a stage requiring referral to an ophthalmologist. Candidate exudates were detected using a multi-scale morphological process. Based on local properties, the likelihoods of a candidate being a member of classes exudate, drusen or background were determined. This leads to a likelihood of the image containing exudates which can be thresholded to create a binary decision. Compared to a clinical reference standard, images containing exudates were detected with sensitivity 95.0% and specificity 84.6% in a test set of 13 219 images of which 300 contained exudates. Depending on requirements, this method could form part of an automated system to detect images showing either any diabetic retinopathy or referable diabetic retinopathy.

  17. Retinal changes in diabetic patients without diabetic retinopathy.

    Science.gov (United States)

    Dumitrescu, Alina Gabriela; Istrate, Sinziana Luminita; Iancu, Raluca Claudia; Guta, Oana Maria; Ciuluvica, Radu; Voinea, Liliana

    2017-01-01

    The purpose of this study was to measure retinal vessel caliber and to examine early changes in macular thickness using optical coherence tomography (OCT). We evaluated to what extend vascular caliber and macular thickness differed between patients with type 2 diabetes mellitus without diabetic retinopathy compared with healthy individuals. 26 diabetic patients without diabetic retinopathy and 26 normal participants without any retinal and optic nerve diseases underwent ophthalmic examination, fundus photography, and OCT imaging. Temporal inferior retinal vessel diameters were measured using OCT. Also, we measured macular thickness in nine ETDRS subfields using Cirrus OCT. The mean age in the diabetic group was 61.5 years and in the control group, 55.5 years. Wider retinal arterioles and venules were found in patients with diabetes compared with healthy subjects (120 µm versus 96 µm, pdiabetes mellitus, central macular thickness was significantly thinner than that of control eyes (243.5 µm versus 269.9 µm, p value diabetes without diabetic retinopathy.

  18. Automated detection of exudates for diabetic retinopathy screening

    Science.gov (United States)

    Fleming, Alan D.; Philip, Sam; Goatman, Keith A.; Williams, Graeme J.; Olson, John A.; Sharp, Peter F.

    2007-12-01

    Automated image analysis is being widely sought to reduce the workload required for grading images resulting from diabetic retinopathy screening programmes. The recognition of exudates in retinal images is an important goal for automated analysis since these are one of the indicators that the disease has progressed to a stage requiring referral to an ophthalmologist. Candidate exudates were detected using a multi-scale morphological process. Based on local properties, the likelihoods of a candidate being a member of classes exudate, drusen or background were determined. This leads to a likelihood of the image containing exudates which can be thresholded to create a binary decision. Compared to a clinical reference standard, images containing exudates were detected with sensitivity 95.0% and specificity 84.6% in a test set of 13 219 images of which 300 contained exudates. Depending on requirements, this method could form part of an automated system to detect images showing either any diabetic retinopathy or referable diabetic retinopathy.

  19. Fruit intake and incident diabetic retinopathy with type 2 diabetes.

    Science.gov (United States)

    Tanaka, Shiro; Yoshimura, Yukio; Kawasaki, Ryo; Kamada, Chiemi; Tanaka, Sachiko; Horikawa, Chika; Ohashi, Yasuo; Araki, Atsushi; Ito, Hideki; Akanuma, Yasuo; Yamada, Nobuhiro; Yamashita, Hidetoshi; Sone, Hirohito

    2013-03-01

    Antioxidants and dietary fiber are postulated to have preventive effects on diabetic retinopathy, but evidence is lacking. We investigated this association in a cohort with type 2 diabetes 40-70 years of age with hemoglobin (Hb)A1C ≥6.5%, originally part of the Japan Diabetes Complications Study. After excluding people who did not respond to a dietary survey and patients with diabetic retinopathy or a major ocular disease at baseline, we analyzed 978 patients. Baseline dietary intake was assessed by a food frequency questionnaire based on food groups and 24-hour dietary records. Primary outcome was incident diabetic retinopathy determined using international severity scales. Mean fruit intake in quartiles ranged from 23 to 253 g/day, with increasing trends across quartiles of fruit intake for vitamin C, vitamin E, carotene, retinol equivalent, dietary fiber, potassium, and sodium. Mean energy intake ranged from 1644 to 1863 kcal/day, and fat intake was approximately 25%. HbA1C, body mass index, triglycerides, and systolic blood pressure were well controlled. During the 8-year follow-up, the numbers of incident cases of diabetic retinopathy from the first through the fourth quartiles of fruit intake were 83, 74, 69, and 59. Multivariate-adjusted hazard ratios for the second, third, and fourth quartiles of fruit intake compared with the first quartile were 0.66 (95% confidence interval = 0.46-0.92), 0.59 (0.41-0.85), and 0.48 (0.32-0.71) (test for trend, P diabetes duration, overweight, smoking, and hypertension. Risk for diabetic retinopathy declined with increased intake of fruits and vegetables, vitamin C, and carotene. Increased fruit intake in ranges commonly consumed was associated with reduced incident diabetic retinopathy among patients adhering to a low-fat energy-restricted diet.

  20. Genome-wide association study of retinopathy in individuals without diabetes.

    Directory of Open Access Journals (Sweden)

    Richard A Jensen

    Full Text Available Mild retinopathy (microaneurysms or dot-blot hemorrhages is observed in persons without diabetes or hypertension and may reflect microvascular disease in other organs. We conducted a genome-wide association study (GWAS of mild retinopathy in persons without diabetes.A working group agreed on phenotype harmonization, covariate selection and analytic plans for within-cohort GWAS. An inverse-variance weighted fixed effects meta-analysis was performed with GWAS results from six cohorts of 19,411 Caucasians. The primary analysis included individuals without diabetes and secondary analyses were stratified by hypertension status. We also singled out the results from single nucleotide polymorphisms (SNPs previously shown to be associated with diabetes and hypertension, the two most common causes of retinopathy.No SNPs reached genome-wide significance in the primary analysis or the secondary analysis of participants with hypertension. SNP, rs12155400, in the histone deacetylase 9 gene (HDAC9 on chromosome 7, was associated with retinopathy in analysis of participants without hypertension, -1.3±0.23 (beta ± standard error, p = 6.6×10(-9. Evidence suggests this was a false positive finding. The minor allele frequency was low (∼2%, the quality of the imputation was moderate (r(2 ∼0.7, and no other common variants in the HDAC9 gene were associated with the outcome. SNPs found to be associated with diabetes and hypertension in other GWAS were not associated with retinopathy in persons without diabetes or in subgroups with or without hypertension.This GWAS of retinopathy in individuals without diabetes showed little evidence of genetic associations. Further studies are needed to identify genes associated with these signs in order to help unravel novel pathways and determinants of microvascular diseases.

  1. Role of VEGF Inhibition in the Treatment of Retinopathy of Prematurity.

    Science.gov (United States)

    Eldweik, Luai; Mantagos, Iason S

    2016-01-01

    Retinopathy of prematurity (ROP) is a potentially blinding disease characterized by retinal neovascularization, which eventually can lead to tractional retinal detachment. Improvements have been made regarding the management of retinopathy of prematurity (ROP) since it was described in the Cryotherapy for Retinopathy of Prematurity study. A more appropriate time for therapeutic intervention was defined by the Early Treatment for Retinopathy of Prematurity (ETROP) trial. Advances in screening strategies with the use of digital imaging systems are now available. All of this and the use of laser photocoagulation and vitreoretinal surgery have contributed to significant increases in favorable outcomes and decreases in child blindness secondary to ROP. Recently the use of vascular endothelial growth factor (VEGF) inhibitors has been introduced to the armamentarium for the treatment of ROP. The purpose of this review article is to evaluate the role of VEGF inhibition in the treatment of ROP.

  2. Cellular defense against singlet oxygen-induced oxidative damage by cytosolic NADP+-dependent isocitrate dehydrogenase.

    Science.gov (United States)

    Kim, Sun Yee; Park, Jeen-Woo

    2003-03-01

    Singlet oxygen (1O2) is a highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules. Recently, we have shown that NADP+-dependent isocitrate dehydrogenase is involved in the supply of NADPH needed for GSH production against cellular oxidative damage. In this study, we investigated the role of cytosolic form of NADP+-dependent isocitrate dehydrogenase (IDPc) against singlet oxygen-induced cytotoxicity by comparing the relative degree of cellular responses in three different NIH3T3 cells with stable transfection with the cDNA for mouse IDPc in sense and antisense orientations, where IDPc activities were 2.3-fold higher and 39% lower, respectively, than that in the parental cells carrying the vector alone. Upon exposure to singlet oxygen generated from photoactivated dye, the cells with low levels of IDPc became more sensitive to cell killing. Lipid peroxidation, protein oxidation, oxidative DNA damage and intracellular peroxide generation were higher in the cell-line expressing the lower level of IDPc. However, the cells with the highly over-expressed IDPc exhibited enhanced resistance against singlet oxygen, compared to the control cells. The data indicate that IDPc plays an important role in cellular defense against singlet oxygen-induced oxidative injury.

  3. Automatic non-proliferative diabetic retinopathy screening system based on color fundus image.

    Science.gov (United States)

    Xiao, Zhitao; Zhang, Xinpeng; Geng, Lei; Zhang, Fang; Wu, Jun; Tong, Jun; Ogunbona, Philip O; Shan, Chunyan

    2017-10-26

    Non-proliferative diabetic retinopathy is the early stage of diabetic retinopathy. Automatic detection of non-proliferative diabetic retinopathy is significant for clinical diagnosis, early screening and course progression of patients. This paper introduces the design and implementation of an automatic system for screening non-proliferative diabetic retinopathy based on color fundus images. Firstly, the fundus structures, including blood vessels, optic disc and macula, are extracted and located, respectively. In particular, a new optic disc localization method using parabolic fitting is proposed based on the physiological structure characteristics of optic disc and blood vessels. Then, early lesions, such as microaneurysms, hemorrhages and hard exudates, are detected based on their respective characteristics. An equivalent optical model simulating human eyes is designed based on the anatomical structure of retina. Main structures and early lesions are reconstructed in the 3D space for better visualization. Finally, the severity of each image is evaluated based on the international criteria of diabetic retinopathy. The system has been tested on public databases and images from hospitals. Experimental results demonstrate that the proposed system achieves high accuracy for main structures and early lesions detection. The results of severity classification for non-proliferative diabetic retinopathy are also accurate and suitable. Our system can assist ophthalmologists for clinical diagnosis, automatic screening and course progression of patients.

  4. Diabetic retinopathy in sub-Saharan Africa: meeting the challenges of an emerging epidemic.

    Science.gov (United States)

    Burgess, Philip I; Msukwa, Gerald; Beare, Nicholas A V

    2013-07-02

    Sub-Saharan Africa faces an epidemic of diabetes. Diabetes causes significant morbidity including visual loss from diabetic retinopathy, which is largely preventable. In this resource-poor setting, health systems are poorly organized to deliver chronic care with multiple system involvement. The specific skills and resources needed to manage diabetic retinopathy are scarce. The costs of inaction for individuals, communities and countries are likely to be high. Screening for and treatment of diabetic retinopathy have been shown to be effective, and cost-effective, in resource-rich settings. In sub-Saharan Africa, clinical services for diabetes need to be expanded with the provision of effective, integrated care, including case-finding and management of diabetic retinopathy. This should be underpinned by a high quality evidence base accounting for differences in diabetes types, resources, patients and society in Africa. Research must address the epidemiology of diabetic retinopathy in Africa, strategies for disease detection and management with laser treatment, and include health economic analyses. Models of care tailored to the local geographic and social context are most likely to be cost effective, and should draw on experience and expertise from other continents. Research into diabetic retinopathy in Africa can drive the political agenda for service development and enable informed prioritization of available health funding at a national level. Effective interventions need to be implemented in the near future to avert a large burden of visual loss from diabetic retinopathy in the continent. An increase in visual loss from diabetic retinopathy is inevitable as the diabetes epidemic emerges in sub-Saharan Africa. This could be minimized by the provision of case-finding and laser treatment, but how to do this most effectively in the regional context is not known. Research into the epidemiology, case-finding and laser treatment of diabetic retinopathy in sub

  5. Bilateral proliferative retinopathy in B-cell acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Devesh Kumawat

    2018-01-01

    Full Text Available A 4-year-old child with B-cell acute lymphoblastic leukemia presented with vitreous hemorrhage due to proliferative retinopathy in both eyes. Pars plana vitrectomy was performed in both eyes to clear nonresolving vitreous hemorrhage after systemic stabilization. Visual recovery was limited by the disc drag in the right eye and subfoveal exudation in the left eye. Etiopathogenesis and management of proliferative retinopathy in acute leukemias are discussed.

  6. Purtscher-like retinopathy: A rare complication of peribulbar anesthesia

    OpenAIRE

    Narendran, Siddharth; Saravanan, V R; Pereira, Merlyn

    2016-01-01

    Purtscher and Purtscher-like retinopathy is a distinctive retinal syndrome characterized by ischemic retinal whitening in a peripapillary pattern. We report a case of Purtscher-like retinopathy in a healthy 64-year-old man after a routine peribulbar anesthetic injection for cataract surgery. Although peribulbar anesthesia is considered to be a safer alternative to retrobulbar anesthesia, it has been associated with unusual but grave complications including central retinal artery occlusion.

  7. Purtscher-like retinopathy: A rare complication of peribulbar anesthesia.

    Science.gov (United States)

    Narendran, Siddharth; Saravanan, V R; Pereira, Merlyn

    2016-06-01

    Purtscher and Purtscher-like retinopathy is a distinctive retinal syndrome characterized by ischemic retinal whitening in a peripapillary pattern. We report a case of Purtscher-like retinopathy in a healthy 64-year-old man after a routine peribulbar anesthetic injection for cataract surgery. Although peribulbar anesthesia is considered to be a safer alternative to retrobulbar anesthesia, it has been associated with unusual but grave complications including central retinal artery occlusion.

  8. Scotoma analysis of 10-2 visual field testing with a white target in screening for hydroxychloroquine retinopathy

    Directory of Open Access Journals (Sweden)

    Browning DJ

    2015-05-01

    Full Text Available David J Browning, Chong Lee Department of Ophthalmology, Charlotte Eye, Ear, Nose and Throat Associates, Charlotte, NC, USA Objective: To quantify the variability of scotomas detected by 10-2 visual field (VF testing in patients taking hydroxychloroquine without and with retinopathy.Design: Retrospective review of clinical charts and visual fields.Subjects: Twenty-one patients taking hydroxychloroquine without retinopathy, and nine patients taking hydroxychloroquine and one patient taking chloroquine with retinopathy.Methods: Retinopathy was defined by annular scotomas on 10-2 VF testing with corroborative spectral domain optical coherence tomographic outer retinal changes and multifocal electroretinographic changes leading to cessation of hydroxychloroquine or chloroquine. Location and depth of scotoma points on 10-2 VF testing were recorded and their fates followed in serial, reliable 10-2 VFs performed with a white target over time.Main outcome measures: Number of scotoma points and locations, percentage of persistent scotoma points, size of scotomas, location of scotomas, and percentage of scotomas deepening.Results: A median of five, interquartile range (IQR 3–8 scotoma points per VF occurred in patients without retinopathy. A median of 86%, IQR 63%–100% of these points resolve on the subsequent field. For patients with retinopathy, a median of 22%, IQR 10%–59% resolve. The median percentage of scotoma points in the zone 2–8 degrees from fixation in eyes with retinopathy was 79%, IQR 68%–85% compared to 60%, IQR 54%–75% in eyes without retinopathy (P=0.0094. Single-point scotomas were more common in eyes without than with retinopathy. Scotomas consisting of more than four contiguous scotoma points were generally indicative of retinopathy.Conclusion: Point scotomas are common and variable in 10-2 VF testing with a white target for hydroxychloroquine retinopathy in subjects without retinopathy. The annular zone 2 to 8

  9. Quantitative analysis of macular retinal thickness and macular volume in diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Ying Zhao

    2017-12-01

    Full Text Available AIM: To evaluate and characterize the macular thickness and macular volume in patients of different stages of diabetic retinopathy with special-domain optical coherence tomography(SD-OCT. METHODS: Totally 40 patients(78 eyeswith diabetic retinopathy were recruited in the study from January 2016 to January 2017 in our hospital. According to the international clinical classification of diabetic retinopathy, 20 cases(40 eyeswere categorized as non-proliferative diabetic retinopathy(NPDRgroup and 20 cases proliferative diabetic retinopathy(PDRgroup(38 eyes. All subjects were examined and analyzed with Early Treatment Diabetic Retinopathy Study(ETDRSsubfields, which were embedded in HS(Haag-Streitwith diameter of 1, 3 and 6mm.The changes of retinal thickness and volume of the macular center were measured. RESULTS: The thickness of macular foveolar in NPDR group and PDR group were 252.57±31.36μm, 362.47±20.81μm. The retinal thickness of inner superior subfield(ISMand inner nasal subfield(INMwere the thickest; that of inner inferior subfield(IIMwas next to ISM and INM, and that of inner temporal subfield was the thinnest. Of the outer subfields, the retinal thickness of outer superior subfield(OSMwas the thickest; that of outer nasal subfield(ONMwas next to OSM, and that of outer temporal subfield(OTMand outer inferior subfield(OIMwas the thinnest. The value of macular central concave thickness and retinal thickness in each quadrant of the NPDR group were less than those of the PDR group, the difference was statistically significant(P3, 0.28±0.16mm3, the upper and nasal sides of the middle part of the partition were the largest, the inferior and the temporal side were the smallest. The nasal side of the outer loop was the largest, the upper was the second, the temporal side and the inferior were the smallest. The volume of macular central fovea and the retinal volume in each quadrant of the NPDR group were smaller than those of the PDR group, the

  10. The expression of the Slit-Robo signal in the retina of diabetic rats and the vitreous or fibrovascular retinal membranes of patients with proliferative diabetic retinopathy.

    Science.gov (United States)

    Zhou, Weiyan; Wang, Hongya; Yu, Wenzhen; Xie, Wankun; Zhao, Min; Huang, Lvzhen; Li, Xiaoxin

    2017-01-01

    The Slit-Robo signal has an important role in vasculogenesis and angiogenesis. Our study examined the expression of Slit2 and its receptor, Robo1, in a rat model of streptozotocin-induced diabetes and in patients with proliferative diabetic retinopathy. Diabetes was induced in male Sprague-Dawley rats via a single, intraperitoneal injection of streptozotocin. The rats were sacrificed 1, 3 or 6 months after the injection. The expression of Slit2 and Robo1 in retinal tissue was measured by real-time reverse transcription polymerase chain reaction (RT-PCR), and protein levels were measured by western blotting and immunohistochemistry. Recombinant N-Slit2 protein was used to study the effects of Slit2 on the expression of VEGF in vivo. The concentration of Slit2 protein in human eyes was measured by enzyme-linked immunosorbent assay in 27 eyes with proliferative diabetic retinopathy and 28 eyes in control group. The expression of Slit2, Robo1 and VEGF in the excised human fibrovascular membranes was examined by fluorescence immunostaining and semi-quantitative RT-PCR. The expression of Slit2 and Robo1 in the retina was altered after STZ injection. Recombinant N-Slit2 protein did not increase the retinal VEGF expression. Vitreous concentrations of Slit2 were significantly higher in the study group than in the control group. In the human fibrovascular membranes of the study group, the co-localization of VEGF with the markers for Slit2 and Robo1was observed. The expression of Slit2 mRNA, Robo1 mRNA, and VEGF mRNA was significantly higher in human fibrovascular proliferative diabetic retinopathy membranes than in the control membranes. The alteration of Slit2 and Robo1 expression in the retinas of diabetic rats and patients with proliferative diabetic retinopathy suggests a role for the Slit-Robo signal in the various stages diabetic retinopathy. Further studies should address the possible involvement of the Slit-Robo signal in the pathophysiological progress of diabetic

  11. Spectral domain optical coherence tomography findings in tamoxifen retinopathy--a case report.

    Science.gov (United States)

    Nair, Sandhya Narayanan; Anantharaman, Giridhar; Gopalakrishnan, Mahesh; Vyas, Jyothiprakash

    2013-01-01

    To report spectral domain optical coherence tomography findings in a case of typical tamoxifen retinopathy. In this observational case report, a patient with tamoxifen retinopathy was imaged with spectral domain optical coherence tomography and fundus auto fluorescence. Spectral domain optical coherence tomography showed numerous hyperreflective spots within the retina, mainly in the inner retinal layers in both the eyes. The external limiting membrane, the Inner Segment-Outer Segment junction, and the photoreceptors were not discernable at the fovea in the right eye. In the left eye, there was foveal atrophy with total loss of photoreceptors. The autofluorescent images showed macular hypofluorescence with foveal hyperfluorescence. Spectral domain optical coherence tomography demonstrated abnormalities in the outer retinal layers in tamoxifen retinopathy. There were also characteristic alterations in the autofluorescence pattern at the macula in tamoxifen retinopathy.

  12. Frequency of diabetic retinopathy in hypertensive diabetic patients in a tertiary care hospital of Peshawar, Pakistan

    International Nuclear Information System (INIS)

    Rahman, S.; Khan, G.J.; Aamir, A.H.

    2011-01-01

    Background: Diabetic retinopathy is a common microvascular complication of both type 1 and type 2 diabetes mellitus. If left untreated, it can progress to serious visual disability. Coexistence of hypertension with diabetes has been described as another risk factor adding to the problem. We designed this study to assess the occurrence of diabetic retinopathy in hypertensive diabetic patients of this region and to compare it with normotensive diabetic patients. Methods: This cross-sectional study was carried out on 200 previously diagnosed diabetic patients. Apart from routine examination and investigations, retinopathy and blood pressure assessment of each patient was done using standard techniques. Hypertensive diabetic subjects (Group-I, n=107) were compared with non-hypertensive diabetics (Group-II, n=93) for the presence of retinopathy. Results: Retinopathy and hypertension were observed in 51% and 53.5% of the total diabetic patients respectively. Hypertensive diabetic patients had significantly higher percentage of retinopathy compared to non-hypertensive diabetic patients (58 vs 43%; p<0.05). Conclusion: Retinopathy and hypertension are highly prevalent in our diabetic patients. The proportion of retinopathy is significantly more in hypertensive as compared to normotensive diabetics. (author)

  13. Update on the Treatment of Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Jennifer L. Wilkinson-Berka

    2008-01-01

    Full Text Available Retinopathy is the most feared complication of diabetes, compromising quality of life in most sufferers. Almost all patients with type 1 diabetes will develop retinopathy over a 15- to 20-year period, and approximately 20–30% will advance to the blinding stage of the disease[1]. Greater than 60% of patients with type 2 diabetes will have retinopathy. This situation is highlighted by the frightening statistic that diabetic retinopathy (DR remains the most common cause of vision impairment in people of working age in Western society. With the global epidemic of type 2 diabetes, this predicament is set to worsen as over 360 million people are projected to suffer from diabetes and its complications by 2030. Vision loss from diabetes is due to a number of factors, including haemorrhage from new and poorly formed blood vessels, retinal detachment due to contraction of deposited fibrous tissue, and neovascular glaucoma resulting in an increase in intraocular pressure. Diabetic macular oedema is now the principal cause of vision loss in diabetes and involves leakage from a disrupted blood-retinal barrier. In terms of treatment, there is clear evidence that strict metabolic and blood pressure control can lower the risk of developing DR and reduce disease progression. Laser photocoagulation and vitrectomy are effective in preventing severe vision loss in DR, particularly in the most advanced stages of the disease. However, both procedures have limitations. This review examines evidence from preclinical and clinical studies that shows that targeting inhibition of the renin-angiotensin system, vascular endothelial growth factor, corticosteroids, protein kinase C, growth hormone, and advanced glycation end-products are potential treatments for DR.

  14. Role of direct funduscopy in screening for diabetic retinopathy in communities

    Directory of Open Access Journals (Sweden)

    Li-Hua Guo

    2016-03-01

    Full Text Available AIM:To observe the application of direct funduscopy in screening for diabetic retinopathy in communities. METHODS:After mydriasis, 265 patients with diabetes mellitus(DMin communities were examined for fundus by direct funduscopy. The patients with diabetic retinopathy(DRwere further received fluorescence fundus angiography(FFAafter referral to superior hospitals.RESULTS:Within the 265 patients with DM, 79 patients were diagnosed as DR and the positive rate of DR was 29.8%. Among the patients with DR, there were 46 patients with non- proliferative diabetic retinopathy(NPDRand 33 patients with proliferative diabetic retinopathy(PDR; the positive rate was respectively 17.4% and 12.5%. All patients with DR were further diagnosed by FFA after referral. Three patients with NPDR were diagnosed with PDR, and 22 patients received laser treatment.CONCLUSION:Ordinary application of direct funduscopy in patients with DM in communities would early detect the DR. It is very necessary to master direct funduscopy for general practitioners.

  15. Open-angle glaucoma in patients with diabetic retinopathy at the Puerto Rico Medical Center.

    Science.gov (United States)

    Cruz-lñigo, Yousef; Izquierdo, Natalio J; García, Omar; Pérez, Raúl

    2012-01-01

    The association of open-angle glaucoma (OAG) with diabetes mellitus remains controversial. We report on the frequency of open-angle glaucoma in patients having diabetic retinopathy in a population of the Puerto Rico Medical Center. A cross-sectional study of 1,442 patients was done. Only the chart of patients 40 years-of-age and older, with a diagnosis of diabetic retinopathy and/or open-angle glaucoma were included. Descriptive analysis was done. Unadjusted and gender-adjusted logistic regression analyses were used to estimate risk of developing open-angle glaucoma in patients with diabetic retinopathy for each subsequent decade. 1,040 patients were diagnosed with diabetic retinopathy from July 1, 2004 to June 30, 2009. Also, 402 patients were diagnosed with open-angle glaucoma from July 1, 2007 to June 30, 2009. Of the 1,040 patients with diabetic retinopathy, 64 patients (6.15%) also had OAG. According to our gender-adjusted logistic regression analysis the estimated risk of developing open-angle glaucoma for patients 40 years-of-age with diabetic retinopathy increased for each subsequent decade until the seventh decade, odds ratio = 5.07 (95% confidence interval: 1.62-15.86). Thereafter, it decreased, odds ratio = 2.07 (95% confidence interval: 0.36-11.82). Our findings suggest that Puerto Rico patients between 40 to 79 years of age with diabetic retinopathy have an increased risk of developing open-angle glaucoma with each subsequent decade. Screening for open-angle glaucoma in patients with diabetic retinopathy is of utmost importance in the aging Puerto Rico population to prevent blindness.

  16. Prevalence of diabetic retinopathy in screening-detected diabetes mellitus: results from the Gutenberg Health Study (GHS).

    Science.gov (United States)

    Ponto, Katharina A; Koenig, Jochem; Peto, Tunde; Lamparter, Julia; Raum, Philipp; Wild, Philipp S; Lackner, Karl J; Pfeiffer, Norbert; Mirshahi, Alireza

    2016-09-01

    Individuals with type 2 diabetes mellitus may experience an asymptomatic period of hyperglycaemia, and complications may already be present at the time of diagnosis. We aimed to determine the prevalence of diabetic retinopathy in patients with newly diagnosed (screening-detected) type 2 diabetes. The Gutenberg Health Study is a population-based study with 15,010 participants aged between 35 and 74 years. We determined the weighted prevalence of diabetic retinopathy by assessing fundus photographs. Screening-detected type 2 diabetes was defined as an HbA1c concentration of 6.5% (47.5 mmol/mol) or more, no medical diagnosis of diabetes and no intake of insulin or oral glucose-lowering agents. Of 14,948 participants, 1377 (9.2%) had diabetes mellitus. Of these, 347 (25.2%) had newly diagnosed type 2 diabetes detected by the screening. Overall, the weighted prevalence of screening-detected type 2 diabetes was 2.1%. Fundus photos were evaluable for 285 (82.1%) participants with newly diagnosed diabetes. The weighted prevalence of diabetic retinopathy in screening-detected type 2 diabetes was 13.0%; 12% of participants had a mild non-proliferative diabetic retinopathy and 0.6% had a moderate non-proliferative diabetic retinopathy. Diabetic retinopathy was proliferative in 0.3%. No cases of severe non-proliferative diabetic retinopathy or diabetic maculopathy were found. Thirty (14.9%) of 202 and six (7.2%) of 83 individuals with and without concomitant arterial hypertension, respectively, had diabetic retinopathy (OR 2.54, 95% CI 1.06, 7.14). Visual acuity did not differ between individuals with and without diabetic retinopathy . In this large European study, the prevalence of diabetic retinopathy in screening-detected type 2 diabetes was 13%. Only a very small proportion of participants with detected diabetic retinopathy needed treatment.

  17. Progress on study of the risk factors of retinopathy of prematurity

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    Hong-Cheng Gao

    2018-01-01

    Full Text Available Retinopathy of prematurity(ROPis an ocular disease caused by retinal ophthalmic dysplasia in premature infants, leads to strabismus, amblyopia, cataract, glaucoma, and even blindness, which seriously affects the quality of life of preterm infants. The infant blindness ratio has climbed to 6%-18%, according to figures released by the World Health Organisation. ROP is the primary cause of blindness in children of the world in recent years. But the pathogenesis of ROP is not yet clear. Gestational age, birth weight, oxygen intake, delivery mode, multiple newborns, neonatal respiratory distress syndrome, anemia, blood transfusion, sepsis, infection, hypercapnia, hyperbilirubinemia, maternal prenatal use of a drug are all the risk factors. We reviewed the risk factors and possible mechanism of ROP, in order to offer theoretical support for the study and prevention of ROP in premature infants.

  18. [Diabetic retinopathy complications--12-year retrospective study].

    Science.gov (United States)

    Ignat, Florica; Davidescu, Livia

    2002-01-01

    It is analyzed, on a retrospective study on 12 years, the incidence of diabetus melitus cases, hospitalized in the Ophthalmologic Clinic from Craiova with special mention to the frequency of the diabetic retinopathy, of it's complications and in an accordance to other general diseases, especially cardiovascular's, which contributes to the aggravation of the diabetic ocular in juries evolution. The study underlines the high incidence of the new founded cases with diabetus melitus in complicated diabetes retinopathy stage; the high frequency of ocular complications is explained, according to our statistic facts and through an insufficient treatment, sometimes incorrect and many other cases total neglected by the patients.

  19. TO STUDY THE EFFECT OF ANGIOTENSIN RECEPTOR BLOCKERS ON DIABETIC RETINOPATHY

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    Chakravarthy K

    2017-05-01

    Full Text Available BACKGROUND Diabetic Retinopathy (DR is the most common microvascular complication of Diabetes Mellitus (DM and is the leading cause of blindness in working age adults of patients with type 1 and 2 DM. Large observational and randomised studies shown that optimal blood glucose and blood pressure control halt or regress the disease and limit the risk of progression to the proliferative stage and visual loss. Recently, evidence has also emerged that Renin-Angiotensin System (RAS inhibitors may electively prevent or delay progression of retinopathy by acting on local RAS. Thus, metabolic and blood pressure control by RAS inhibition is to prevent or limit the onset of retinopathy and its progression towards visual-threatening stages. The aim of the study is to categorise and analyse grading of DR who are on currently ACE and ARBs unchanged for at least 2 years. MATERIALS AND METHODS 178 patients with type 1 and 2 DM of both genders on ARBs and ACEI unchanged for at least 2 years are divided into two groups as follows- 1. ARB group, which includesa 28 patients on losartan (50 mg. b 32 patients on losartan (50 mg + hydrochlorothiazide (12.5 mg. c 28 patients on telmisartan (40 mg. d 32 patients on telmisartan (40 mg + hydrochlorothiazide (12.5 mg. 2. ACE inhibitor group includesa 30 patients on enalapril (5 mg. b 28 patients on ramipril (2.5 mg + hydrochlorothiazide (12.5 mg. Retinopathy grading assessed by indirect ophthalmoscope and comparison of retinopathy grading between ARBs and ACEI groups have done. Two-tailed Chi-square test, GraphPad Prism Software used for statistical calculations. RESULTS Losartan and telmisartan (ARB group showed significant protection from diabetic retinopathy than enalapril and ramipril (ACEI group (p<0.05. CONCLUSION ARBs help in preventing the progression of DR and vision loss in those belonging to mild and moderate nonproliferative diabetic retinopathy patients.

  20. Purtscher-like retinopathy: A rare complication of peribulbar anesthesia

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    Siddharth Narendran

    2016-01-01

    Full Text Available Purtscher and Purtscher-like retinopathy is a distinctive retinal syndrome characterized by ischemic retinal whitening in a peripapillary pattern. We report a case of Purtscher-like retinopathy in a healthy 64-year-old man after a routine peribulbar anesthetic injection for cataract surgery. Although peribulbar anesthesia is considered to be a safer alternative to retrobulbar anesthesia, it has been associated with unusual but grave complications including central retinal artery occlusion.

  1. Maternal Iron Deficiency Anemia as a Risk Factor for the Development of Retinopathy of Prematurity.

    Science.gov (United States)

    Dai, Alper I; Demiryürek, Seniz; Aksoy, Sefika Nur; Perk, Peren; Saygili, Oguzhan; Güngör, Kivanc

    2015-08-01

    Retinopathy of prematurity is a proliferative vascular disease affecting premature newborns and occurs during vessel development and maturation. The aim of this study was to evaluate the maternal iron deficiency anemia as possible risk factors associated with the development of retinopathy of prematurity among premature or very low birth weight infants. In this study, mothers of 254 infants with retinopathy of prematurity were analyzed retrospectively, and their laboratory results of medical records during pregnancy were reviewed for possible iron deficiency anemia. In a cohort of 254 mothers of premature infants with retinopathy of prematurity, 187 (73.6%) had iron deficiency, while the remaining 67 (26.4%) mothers had no deficiency. Babies born to mothers with iron deficiency anemia with markedly decreased hemoglobin, hematocrit, mean corpuscular volume, serum iron, and ferritin levels were more likely to develop retinopathy of prematurity. Our results are the first to suggest that maternal iron deficiency is a risk factor for the development of retinopathy of prematurity. Our data suggest that maternal iron supplementation therapy during pregnancy might lower the risk of retinopathy of prematurity. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Controlled oxygen vacancy induced p-type conductivity in HfO{sub 2-x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrandt, Erwin; Kurian, Jose; Mueller, Mathis M.; Kleebe, Hans-Joachim; Alff, Lambert [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany); Schroeder, Thomas [IHP, 15236 Frankfurt/Oder (Germany)

    2011-09-12

    We have synthesized highly oxygen deficient HfO{sub 2-x} thin films by controlled oxygen engineering using reactive molecular beam epitaxy. Above a threshold value of oxygen vacancies, p-type conductivity sets in with up to 6 times 10{sup 21} charge carriers per cm{sup 3}. At the same time, the band-gap is reduced continuously by more than 1 eV. We suggest an oxygen vacancy induced p-type defect band as origin of the observed behavior.

  3. Anisotropic chemical strain in cubic ceria due to oxygen-vacancy-induced elastic dipoles.

    Science.gov (United States)

    Das, Tridip; Nicholas, Jason D; Sheldon, Brian W; Qi, Yue

    2018-06-06

    Accurate characterization of chemical strain is required to study a broad range of chemical-mechanical coupling phenomena. One of the most studied mechano-chemically active oxides, nonstoichiometric ceria (CeO2-δ), has only been described by a scalar chemical strain assuming isotropic deformation. However, combined density functional theory (DFT) calculations and elastic dipole tensor theory reveal that both the short-range bond distortions surrounding an oxygen-vacancy and the long-range chemical strain are anisotropic in cubic CeO2-δ. The origin of this anisotropy is the charge disproportionation between the four cerium atoms around each oxygen-vacancy (two become Ce3+ and two become Ce4+) when a neutral oxygen-vacancy is formed. Around the oxygen-vacancy, six of the Ce3+-O bonds elongate, one of the Ce3+-O bond shorten, and all seven of the Ce4+-O bonds shorten. Further, the average and maximum chemical strain values obtained through tensor analysis successfully bound the various experimental data. Lastly, the anisotropic, oxygen-vacancy-elastic-dipole induced chemical strain is polarizable, which provides a physical model for the giant electrostriction recently discovered in doped and non-doped CeO2-δ. Together, this work highlights the need to consider anisotropic tensors when calculating the chemical strain induced by dilute point defects in all materials, regardless of their symmetry.

  4. Clinical Investigation of Radiation Retinopathy Fundus and Fluorescein Angiographic Features

    Institute of Scientific and Technical Information of China (English)

    LiMei; QiuGT

    1999-01-01

    Purpose:To investigate the fundus and fluorescein angiographic features in the patients with radiation retinopathy.Clinical Materials:Color fundus photography and/or fluorescein angiography from 13 patients with nasopharyngeal carcinomas received external beam radiation were retrospectively analyzed.Reslts:In this study,26 damaged eyes of 13 patients eveloped some degree of radiation retinopathy.The earliest and most common finding was macular microvascular changes (microaneurysms and/or telangiectasia),which was observed in 100%(26/26)of the eyes.Intraretinal hemorrhages,macular capillary nonperfusion,and macular edema were noted in 84%,50%,and 42% of the eyes,respectively.Conclusions:Radiation retinopathy is common after external beam radiation of nasopharyngeal carcinomas.The prominent changes include maular microvascular changes,intraretinal hemorrhages and macular capillary nonperfusion.

  5. Retinopathy risk factors among diabetics in a tertiary care military hospital

    International Nuclear Information System (INIS)

    Nizi, M.K.; Ameen, S.S.; Saeed, K.; Yaqub, M.A.; Khan, M.D.; Arain, M.A.

    2011-01-01

    Objective: To determine the frequency and risk factors for severity of retinopathy in diabetic patients referred to a tertiary military hospital. Study Design: Cross-sectional study. Place and duration of study: Armed Forces Institute of Ophthalmology, Rawalpindi from Jun 2008 to Dec 2009. Patients and Methods: Diabetic patients aged 40 to 79, referred for suspected diabetic retinopathy (DR) on fundoscopy from medical outpatient clinic of Military Hospital Rawalpindi were randomly included in the study. Participants underwent a standardized interview and examination. Retinopathy was assessed through dilated pupils, and graded into absent retinopathy, mild to moderate, or advanced. Presence of clinically significant macular edema (CSME) was also recorded. To evaluate the simultaneous effect of significant risk factors on the different stages of DR, multivariate regression analysis was carried out. Results: Out of five hundred and ten patients, DR was confirmed in 63% cases with advanced retinopathy in 21.3%. In univariate analysis, duration of diabetes, fasting blood glucose, and presence of macular oedema were significantly associated with retinopathy (P<0.005). On multivariate analysis, however, only duration of diabetes (Odds Ratio 6.15 for 5 to 10 years and 38.29 for more than 10 years) and macular oedema (OR 6.617 95% CI 3.95-11.07) remained significant. CSME was present in 173 (33%) patients and its frequency increased with the severity of DR (P <0.001). Conclusion: The frequency of DR among military personnel and their dependants was high with strong association to duration of diabetes. This underscores the importance of regular retinal examination to detect DR in the early stages and timely intervention to prevent diabetes related blindness. (author)

  6. Grading and disease management in national screening for diabetic retinopathy in England and Wales.

    Science.gov (United States)

    Harding, S; Greenwood, R; Aldington, S; Gibson, J; Owens, D; Taylor, R; Kohner, E; Scanlon, P; Leese, G

    2003-12-01

    A National Screening Programme for diabetic eye disease in the UK is in development. We propose a grading and early disease management protocol to detect sight-threatening diabetic retinopathy and any retinopathy, which will allow precise quality assurance at all steps while minimizing false-positive referral to the hospital eye service. Expert panel structured discussions between 2000 and 2002 with review of existing evidence and grading classifications. Principles of the protocol include: separate grading of retinopathy and maculopathy, minimum number of steps, compatible with central monitoring, expandable for established more complex systems and for research, no lesion counting, no 'questionable' lesions, attempt to detect focal exudative, diffuse and ischaemic maculopathy and fast track referral from primary or secondary graders. Sight-threatening diabetic retinopathy is defined as: preproliferative retinopathy or worse, sight-threatening maculopathy and/or the presence of photocoagulation. In the centrally reported minimum data set retinopathy is graded into four levels: none (R0), background (R1), preproliferative (R2), proliferative (R3). Maculopathy and photocoagulation are graded as absent (M0, P0) or present (M1, P1). The protocol developed by the Diabetic Retinopathy Grading and Disease Management Working Party represents a new consensus upon which national guidelines can be based leading to the introduction of quality-assured screening for people with diabetes.

  7. Serum Lipids and Diabetic Retinopathy in Newly Diagnosed Type 2 Diabetic Subjects

    Directory of Open Access Journals (Sweden)

    Shahana Shermin

    2011-07-01

    Full Text Available Background: Diabetic retinopathy is the commonest and usually the first observable vascular complication of diabetes mellitus. Along with hyperglycaemia, dyslipidaemia is a contributing factor for the occurrence of diabetic retinopathy. It is postulated that dyslipidaemia results in formation of hard exudate by increasing blood viscosity and altering the fibrinolytic system. A case control study was carried out in the department of Biochemistry, Bangabandhu Sheikh Mujib Medical University, Dhaka during the period of January 2006 to December 2007 to evaluate the serum lipid profile in newly diagnosed type 2 diabetic subjects with diabetic retinopathy. Materials and Methods: Total 85 newly diagnosed type 2 diabetic subjects were included in this study, 40 were cases having retinopathy and 45 were age and sex matched controls without retinopathy. Serum triglyceride (TG, total cholesterol (TC, low density lipoprotein cholesterol (LDL-C and high density lipoprotein cholesterol (HDL-C were compared between cases and controls. Unpaired t-test and chi-square test were done between groups as tests of significance. Results: All the parameters of lipid profile showed dyslipidaemic trend both in cases and controls. In the cases TG was significantly higher and HDL-C was significantly lower than that of controls (p < 0.05 whereas no significant difference was found between cases and controls with respect to serum TC and LDL-C. Conclusion: It can be concluded that high TG and low HDL-C are associated with diabetic retinopathy in newly diagnosed type 2 diabetes.

  8. Retinopatia hipertensiva: revisão Hypertensive retinopathy: review

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    Aurélio Paulo Batista da Silva

    2002-08-01

    Full Text Available O presente estudo faz uma revisão do tema retinopatia hipertensiva. Para tanto propôs-se uma breve revisão dos dados históricos da retinopatia hipertensiva. Este estudo relata as alterações clássicas da retinopatia hipertensiva e suas classificações, bem como os achados mais recentes associados à hipertensão arterial sistêmica, os prováveis mecanismos fisiopatológicos e as alterações histológicas associadas à retinopatia hipertensiva. Abordamos, ainda, os diversos métodos utilizados para a investigação, suas vantagens e desvantagens; uma visão crítica da interpretação dos sinais do envolvimento do bulbo ocular pela hipertensão arterial sistêmica; ainda, baseado na diversidade das metodologias de investigação da retinopatia, comenta-se a repercussão desta, na prevalência da retinopatia hipertensiva e suas implicações, como órgão-alvo da hipertensão arterial sistêmica, em um contexto atualizado da síndrome metabólica e de outros fatores associados à fisiopatologia da HAS, como a leptina e a endotelina.The present study carries out a review of the theme hypertensive retinopathy. Thus it presents a brief review of the historical data on hypertensive retinopathy. The study reports the classical alterations of hypertensive retinopathy and its classifications, as well as the most recent findings associated with systemic arterial hypertension, the likely patho-physiological mechanisms, and the several methods used for investigation, their advantages and disadvantages; a critical view of the interpretation of signs of the ocular bulb involvement by systemic arterial hypertension; furthermore, based on the diversity of methodologies used in the investigation of retinopathy, comments are made on its reverberation, in the prevalence of hypertensive retinopathy and its implications, as a target organ of systemic arterial hypertension, in an updated context of the metabolic syndrome and of other elements associated with

  9. The role of serum apelin in retinopathy of prematurity

    Directory of Open Access Journals (Sweden)

    Ali YF

    2017-02-01

    Full Text Available Yasser F Ali,1 Salah El-Morshedy,1 Abdulbasit Abdulhalim Imam,2 Nasser Ismai A Abdelrahman,1 Riad M Elsayed,3 Usama M Alkholy,1 Nermin Abdalmonem,1 Mohammed M Shehab1 1Department of Pediatrics, Faculty of Medicine, Zagazig University, Zagazig, 2Department of Pediatrics, Al-Azhar Faculty of Medicine-Girls, Cairo, 3Pediatric Neurology Unit, Pediatric Department, Mansoura University, Mansoura, Egypt Objective: To evaluate the role of serum apelin as a diagnostic tool in retinopathy of prematurity (ROP disease.Patients and methods: Thirty-eight preterm infants (60% male with gestational age ranging from 30 to 36 weeks admitted to the neonatal intensive care unit, KJO Hospital, Saudi Arabia with proven diagnosis of ROP were included in the study. In addition, 27 preterm infants without ROP served as controls. All newborn infants in the study were subjected to adequate history taking, full clinical examination, and fundus examination by indirect ophthalmoscope (at 4–6 weeks as well as determination of serum apelin at birth and at 4–6 weeks of age.Results: The study revealed that oxygen therapy longer than 7 days’ duration, cesarean section (as a mode of delivery, sepsis, mechanical ventilation, blood transfusion, premature rupture of membranes, pneumothorax, perinatal asphyxia, cardiac problems, and neonatal jaundice were considered as risk factors related to development of ROP. Serum apelin levels were significantly lower in patients than controls (P<0.001 at time of diagnosis of the disease (4–6 weeks while no significant differences were observed in levels at birth.Conclusion: Serum apelin was found to be of significant diagnostic value in the occurrence of ROP. Keywords: retinopathy of prematurity, preterm infants, serum apelin

  10. Hyperbaric oxygen therapy for the treatment of radiation-induced macular ischemia

    Directory of Open Access Journals (Sweden)

    Shamim A Haji

    2010-05-01

    Full Text Available Shamim A Haji1,2, Ronald EP Frenkel1,2,31Eye Research Foundation, Stuart, FL, USA; 2East Florida Eye Institute, Stuart, FL, USA; 3Bascom Palmer Eye Institute, Miami, FL, USAPurpose: To report a case of radiation-induced macular ischemia where vision and macular perfusion improved after hyperbaric oxygen (HBO therapy.Methods: A 62-year-old male patient developed radiation-induced macular ischemia after he was treated with radiation for brain glioma. The patient presented with best spectacle-corrected visual acuity (BSCVA acuity of 20/400 in his right eye. Optical coherence tomography (OCT showed central macular thickness of 468 μm. The patient received focal laser, intravitreal triamcinolone, and HBO therapy.Results: The patient’s vision improved from 20/400 to 20/100 after focal laser and intravitreal triamcinolone. His central macular thickness improved from 468 μm to 132 μm. After receiving HBO therapy, his VA improved to 20/50 and fluorescein angiography showed improvement in macular perfusion.Conclusion: HBO therapy improves macular perfusion in patients with radiation-induced macular ischemia.Keywords: macular ischemia, visual acuity, hyperbaric oxygen therapy, macular perfusion

  11. [Retinopathy of prematurity].

    Science.gov (United States)

    Promelle, V; Milazzo, S

    2017-05-01

    Retinopathy of prematurity is a retinal vasoproliferative disease affecting extremely preterm infants exposed to high concentrations of oxygen therapy. Infants born before 32 post-menstrual weeks or with a birth weight of less than 1500g should systematically have a dilated fundus examination. The time of screening and schedule for follow-up are guided by the various risk factors. This disease results from immaturity of the peripheral retinal vessels at the time of premature birth. The classification of ROP depends on the anteroposterior extent of involvement (from center to periphery: zone I, II and III), its extension in 30° sectors (clock hours) and its stage (stage 1 to 5). "Plus" disease is defined as dilation and tortuosity of the retinal blood vessels in the posterior pole of the eye and represents a major risk factor for rapid unfavorable progression. A majority of patients will spontaneously recover, but patients with a high risk of progression will require treatment to prevent retinal detachment and blindness. The indications for treatment are threshold disease and type 1 pre-threshold disease. The current treatment of choice is peripheral retinal ablation with transpupillary laser, but ab externo cryotherapy may be used instead. Intravitreal injection of vascular endothelial growth factor inhibitors may be an attractive therapeutic option and is currently under investigation. After laser treatment, unfavorable outcomes occur in only 9 to 14 % of eyes, but at the price of peripheral retinal destruction. For all patients, whether treated or not, a regular fundus examination should be insured until complete retinal vascularization has occurred. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Presence of chronic diabetic foot ulcers is associated with more frequent and more advanced retinopathy.

    Science.gov (United States)

    Sellman, A; Katzman, P; Andreasson, S; Löndahl, M

    2018-05-23

    To clarify the frequency and severity of diabetic retinopathy in a group of people with Type 2 diabetes and chronic diabetic foot ulcers, and to compare visual acuity, levels of retinopathy and clinical significant macular oedema with a matched control group of people with Type 2 diabetes without a history of chronic diabetic foot ulcers. Visual acuity and fundus imaging were evaluated in 90 white people with at least 3 months' duration of full-thickness diabetic foot ulcers below the ankle and the results compared with those in 180 white people with Type 2 diabetes without a history of chronic diabetic foot ulcers (control group). Controls were matched for age, sex and duration of diabetes. Despite similar age and diabetes duration, severe non-proliferative or proliferative diabetic retinopathy was present in 41% of the people in the diabetic foot ulcer group as compared to 15% in the control group (Pdiabetic foot ulcer group was without any diabetic retinopathy as compared to 34% among controls. Proliferative diabetic retinopathy was more common in the diabetic foot ulcer group (31% vs 8%; Pdiabetic retinopathy did not differ between groups. Clinically significant macular oedema was more frequently present, and the diabetic foot ulcer group exhibited significantly worse results in best and worst eye visual acuity testing. In this northern European setting almost all people with Type 2 diabetes and chronic diabetic foot ulcers had diabetic retinopathy. Almost one-third had proliferative diabetic retinopathy as compared to diabetic retinopathy was linked to worse visual acuity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. A model study of warming-induced phosphorus-oxygen feedbacks in open-ocean oxygen minimum zones on millennial timescales

    Science.gov (United States)

    Niemeyer, Daniela; Kemena, Tronje P.; Meissner, Katrin J.; Oschlies, Andreas

    2017-05-01

    Observations indicate an expansion of oxygen minimum zones (OMZs) over the past 50 years, likely related to ongoing deoxygenation caused by reduced oxygen solubility, changes in stratification and circulation, and a potential acceleration of organic matter turnover in a warming climate. The overall area of ocean sediments that are in direct contact with low-oxygen bottom waters also increases with expanding OMZs. This leads to a release of phosphorus from ocean sediments. If anthropogenic carbon dioxide emissions continue unabated, higher temperatures will cause enhanced weathering on land, which, in turn, will increase the phosphorus and alkalinity fluxes into the ocean and therefore raise the ocean's phosphorus inventory even further. A higher availability of phosphorus enhances biological production, remineralisation and oxygen consumption, and might therefore lead to further expansions of OMZs, representing a positive feedback. A negative feedback arises from the enhanced productivity-induced drawdown of carbon and also increased uptake of CO2 due to weathering-induced alkalinity input. This feedback leads to a decrease in atmospheric CO2 and weathering rates. Here, we quantify these two competing feedbacks on millennial timescales for a high CO2 emission scenario. Using the University of Victoria (UVic) Earth System Climate Model of intermediate complexity, our model results suggest that the positive benthic phosphorus release feedback has only a minor impact on the size of OMZs in the next 1000 years. The increase in the marine phosphorus inventory under assumed business-as-usual global warming conditions originates, on millennial timescales, almost exclusively (> 80 %) from the input via terrestrial weathering and causes a 4- to 5-fold expansion of the suboxic water volume in the model.

  14. A model study of warming-induced phosphorus–oxygen feedbacks in open-ocean oxygen minimum zones on millennial timescales

    Directory of Open Access Journals (Sweden)

    D. Niemeyer

    2017-05-01

    Full Text Available Observations indicate an expansion of oxygen minimum zones (OMZs over the past 50 years, likely related to ongoing deoxygenation caused by reduced oxygen solubility, changes in stratification and circulation, and a potential acceleration of organic matter turnover in a warming climate. The overall area of ocean sediments that are in direct contact with low-oxygen bottom waters also increases with expanding OMZs. This leads to a release of phosphorus from ocean sediments. If anthropogenic carbon dioxide emissions continue unabated, higher temperatures will cause enhanced weathering on land, which, in turn, will increase the phosphorus and alkalinity fluxes into the ocean and therefore raise the ocean's phosphorus inventory even further. A higher availability of phosphorus enhances biological production, remineralisation and oxygen consumption, and might therefore lead to further expansions of OMZs, representing a positive feedback. A negative feedback arises from the enhanced productivity-induced drawdown of carbon and also increased uptake of CO2 due to weathering-induced alkalinity input. This feedback leads to a decrease in atmospheric CO2 and weathering rates. Here, we quantify these two competing feedbacks on millennial timescales for a high CO2 emission scenario. Using the University of Victoria (UVic Earth System Climate Model of intermediate complexity, our model results suggest that the positive benthic phosphorus release feedback has only a minor impact on the size of OMZs in the next 1000 years. The increase in the marine phosphorus inventory under assumed business-as-usual global warming conditions originates, on millennial timescales, almost exclusively (> 80 % from the input via terrestrial weathering and causes a 4- to 5-fold expansion of the suboxic water volume in the model.

  15. Exhaustive Exercise-induced Oxidative Stress Alteration of Erythrocyte Oxygen Release Capacity.

    Science.gov (United States)

    Xiong, Yanlian; Xiong, Yanlei; Wang, Yueming; Zhao, Yajin; Li, Yaojin; Ren, Yang; Wang, Ruofeng; Zhao, Mingzi; Hao, Yitong; Liu, Haibei; Wang, Xiang

    2018-05-24

    The aim of the present study is to explore the effect of exhaustive running exercise (ERE) in the oxygen release capacity of rat erythrocytes. Rats were divided into sedentary control (C), moderate running exercise (MRE) and exhaustive running exercise groups. The thermodynamics and kinetics properties of the erythrocyte oxygen release process of different groups were tested. We also determined the degree of band-3 oxidative and phosphorylation, anion transport activity and carbonic anhydrase isoform II(CAII) activity. Biochemical studies suggested that exhaustive running significantly increased oxidative injury parameters in TBARS and methaemoglobin levels. Furthermore, exhaustive running significantly decreased anion transport activity and carbonic anhydrase isoform II(CAII) activity. Thermodynamic analysis indicated that erythrocytes oxygen release ability also significantly increased due to elevated 2,3-DPG level after exhaustive running. Kinetic analysis indicated that exhaustive running resulted in significantly decreased T50 value. We presented evidence that exhaustive running remarkably impacted thermodynamics and kinetics properties of RBCs oxygen release. In addition, changes in 2,3-DPG levels and band-3 oxidation and phosphorylation could be the driving force for exhaustive running induced alterations in erythrocytes oxygen release thermodynamics and kinetics properties.

  16. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling☆

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-01-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2.) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. PMID:26225731

  17. Hyperbaric oxygenation was effective in a case of radiation-induced optic neuropathy

    International Nuclear Information System (INIS)

    Saitoh, Ayumi; Dake, Yoshinori; Amemiya, Tsugio

    1995-01-01

    A 68-year-old female underwent radiation treatment followed by surgical extirpation for olfactory neuroblastoma in the left ethmoidal sinus. Acute optic neuropathy developed 16 months later in her left eye. The visual acuity was reduced to finger counting at 30 cm. Treatment with systemic corticosteroid and hyperbaric oxygenation for 2 months resulted in improvement in fundus findings and improvement of visual acuity to 0.5. The findings show the potential effectiveness of hyperbaric oxygen therapy for radiation-induced optic neuropathy. (author)

  18. Hyperbaric oxygenation was effective in a case of radiation-induced optic neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, Ayumi; Dake, Yoshinori; Amemiya, Tsugio [Nagasaki Univ. (Japan). School of Medicine

    1995-03-01

    A 68-year-old female underwent radiation treatment followed by surgical extirpation for olfactory neuroblastoma in the left ethmoidal sinus. Acute optic neuropathy developed 16 months later in her left eye. The visual acuity was reduced to finger counting at 30 cm. Treatment with systemic corticosteroid and hyperbaric oxygenation for 2 months resulted in improvement in fundus findings and improvement of visual acuity to 0.5. The findings show the potential effectiveness of hyperbaric oxygen therapy for radiation-induced optic neuropathy. (author).

  19. Interaction of light with the ZnO surface: Photon induced oxygen “breathing,” oxygen vacancies, persistent photoconductivity, and persistent photovoltage

    International Nuclear Information System (INIS)

    Gurwitz, Ron; Cohen, Rotem; Shalish, Ilan

    2014-01-01

    ZnO surfaces adsorb oxygen in the dark and emit CO 2 when exposed to white light, reminiscent of the lungs of living creatures. We find that this exchange of oxygen with the ambient affects the integrity of the ZnO surface. Thus, it forms a basis for several interesting surface phenomena in ZnO, such as photoconductivity, photovoltage, and gas sensing, and has a role in ZnO electrical conduction. Using x-ray photoelectron spectroscopy on ZnO nanowires, we observed a decomposition of ZnO under white light and formation of oxygen-depleted surface, which explains photoconductivity by the electron donation of oxygen vacancies. Our findings suggest that the observed decomposition of the ZnO lattice may only take place due to photon-induced reduction of ZnO by carbon containing molecules (or carbo-photonic reduction), possibly from the ambient gas, accounting in a consistent way for both the reduced demands on the energy required for decomposition and for the observed emission of lattice oxygen in the form of CO 2 . The formation of oxygen-vacancy rich surface is suggested to induce surface delta doping, causing accumulation of electrons at the surface, which accounts for both the increase in conductivity and the flattening of the energy bands. Using surface photovoltage spectroscopy in ultra high vacuum, we monitored changes in the deep level spectrum. We observe a wide optical transition from a deep acceptor to the conduction band, which energy position coincides with the position of the so called “green luminescence” in ZnO. This green transition disappears with the formation of surface oxygen vacancies. Since the oxygen vacancies are donors, while the green transition involves surface acceptors, the results suggest that the initial emission of oxygen originates at the defect sites of the latter, thereby eliminating each other. This suggests that the green transition originates at surface Zn vacancy acceptors. Removing an oxygen atom from a Zn vacancy completes

  20. Interaction of light with the ZnO surface: Photon induced oxygen “breathing,” oxygen vacancies, persistent photoconductivity, and persistent photovoltage

    Energy Technology Data Exchange (ETDEWEB)

    Gurwitz, Ron; Cohen, Rotem; Shalish, Ilan, E-mail: shalish@ee.bgu.ac.il [Ben Gurion University, Beer Sheva 84105 (Israel)

    2014-01-21

    ZnO surfaces adsorb oxygen in the dark and emit CO{sub 2} when exposed to white light, reminiscent of the lungs of living creatures. We find that this exchange of oxygen with the ambient affects the integrity of the ZnO surface. Thus, it forms a basis for several interesting surface phenomena in ZnO, such as photoconductivity, photovoltage, and gas sensing, and has a role in ZnO electrical conduction. Using x-ray photoelectron spectroscopy on ZnO nanowires, we observed a decomposition of ZnO under white light and formation of oxygen-depleted surface, which explains photoconductivity by the electron donation of oxygen vacancies. Our findings suggest that the observed decomposition of the ZnO lattice may only take place due to photon-induced reduction of ZnO by carbon containing molecules (or carbo-photonic reduction), possibly from the ambient gas, accounting in a consistent way for both the reduced demands on the energy required for decomposition and for the observed emission of lattice oxygen in the form of CO{sub 2}. The formation of oxygen-vacancy rich surface is suggested to induce surface delta doping, causing accumulation of electrons at the surface, which accounts for both the increase in conductivity and the flattening of the energy bands. Using surface photovoltage spectroscopy in ultra high vacuum, we monitored changes in the deep level spectrum. We observe a wide optical transition from a deep acceptor to the conduction band, which energy position coincides with the position of the so called “green luminescence” in ZnO. This green transition disappears with the formation of surface oxygen vacancies. Since the oxygen vacancies are donors, while the green transition involves surface acceptors, the results suggest that the initial emission of oxygen originates at the defect sites of the latter, thereby eliminating each other. This suggests that the green transition originates at surface Zn vacancy acceptors. Removing an oxygen atom from a Zn vacancy

  1. Retinopathy after low dose irradiation for an intracranial tumor of the frontal lobe

    International Nuclear Information System (INIS)

    Elsaas, T.; Thorud, E.; Jetne, V.; Conradi, I.S.

    1988-01-01

    A 32-year-old man underwent an operation for an oligodendroglioma of the left frontal lobe. Postoperatively he was irradiated to a target dose of 54 Gy. One year later hedeveloped bilateral retinopathy quite similar to diabetic retinopathy. There were no clinical or biochemical signs of diabetes or hematological disease. The calcultated maximum dose to the retina was 11 Gy. This is to our knowledge the lowest retinal dose of ionizing radiation reported to produce retinopathy. (author)

  2. Emerging roles of hypoxia-inducible factors and reactive oxygen species in cancer and pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Shigeo Saito

    2015-06-01

    Full Text Available Eukaryotic organisms require oxygen homeostasis to maintain proper cellular function for survival. During conditions of low oxygen tension (hypoxia, cells activate the transcription of genes that induce an adaptive response, which supplies oxygen to tissues. Hypoxia and hypoxia-inducible factors (HIFs may contribute to the maintenance of putative cancer stem cells, which can continue self-renewal indefinitely and express stemness genes in hypoxic stress environments (stem cell niches. Reactive oxygen species (ROS have long been recognized as toxic by-products of aerobic metabolism that are harmful to living cells, leading to DNA damage, senescence, or cell death. HIFs may promote a cancer stem cell state, whereas the loss of HIFs induces the production of cellular ROS and activation of proteins p53 and p16Ink4a, which lead to tumor cell death and senescence. ROS seem to inhibit HIF regulation in cancer cells. By contrast, controversial data have suggested that hypoxia increases the generation of ROS, which prevents hydroxylation of HIF proteins by inducing their transcription as negative feedback. Moreover, hypoxic conditions enhance the generation of induced pluripotent stem cells (iPSCs. During reprogramming of somatic cells into a PSC state, cells attain a metabolic state typically observed in embryonic stem cells (ESCs. ESCs and iPSCs share similar bioenergetic metabolisms, including decreased mitochondrial number and activity, and induced anaerobic glycolysis. This review discusses the current knowledge regarding the emerging roles of ROS homeostasis in cellular reprogramming and the implications of hypoxic regulation in cancer development.

  3. NOX2-Induced Activation of Arginase and Diabetes-Induced Retinal Endothelial Cell Senescence

    Directory of Open Access Journals (Sweden)

    Modesto Rojas

    2017-06-01

    Full Text Available Increases in reactive oxygen species (ROS and decreases in nitric oxide (NO have been linked to vascular dysfunction during diabetic retinopathy (DR. Diabetes can reduce NO by increasing ROS and by increasing activity of arginase, which competes with nitric oxide synthase (NOS for their commons substrate l-arginine. Increased ROS and decreased NO can cause premature endothelial cell (EC senescence leading to defective vascular repair. We have previously demonstrated the involvement of NADPH oxidase 2 (NOX2-derived ROS, decreased NO and overactive arginase in DR. Here, we investigated their impact on diabetes-induced EC senescence. Studies using diabetic mice and retinal ECs treated with high glucose or H2O2 showed that increases in ROS formation, elevated arginase expression and activity, and decreased NO formation led to premature EC senescence. NOX2 blockade or arginase inhibition prevented these effects. EC senescence was also increased by inhibition of NOS activity and this was prevented by treatment with a NO donor. These results indicate that diabetes/high glucose-induced activation of arginase and decreases in NO bioavailability accelerate EC senescence. NOX2-generated ROS contribute importantly to this process. Blockade of NOX2 or arginase represents a strategy to prevent diabetes-induced premature EC senescence by preserving NO bioavailability.

  4. Does renin-angiotensin system blockade have a role in preventing diabetic retinopathy? A clinical review

    DEFF Research Database (Denmark)

    Sjølie, A K; Dodson, P; Hobbs, F R R

    2011-01-01

    Diabetes management has increasingly focused on the prevention of macrovascular disease, in particular for type 2 diabetes. Diabetic retinopathy, one of the main microvascular complications of diabetes, is also an important public health problem. Much of the care invested in retinopathy relates...... the primary trial end-points were not met, there was a clear trend to less severe retinopathy with RAS blockade. A smaller trial, RASS, reported reduced retinopathy progression in type 1 diabetes from RAS blockade with both the ARB losartan and the angiotensin converting enzyme (ACE) inhibitor enalapril...

  5. Protective Effects of Melatonin on Retinal Inflammation and Oxidative Stress in Experimental Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Tingting Jiang

    2016-01-01

    Full Text Available Oxidative stress and inflammation are important pathogenic factors contributing to the etiology of diabetic retinopathy (DR. Melatonin is an endogenous hormone that exhibits a variety of biological effects including antioxidant and anti-inflammatory functions. The goals of this study were to determine whether melatonin could ameliorate retinal injury and to explore the potential mechanisms. Diabetes was induced by a single intraperitoneal (i.p. injection of STZ (60 mg/kg in Sprague-Dawley rats. Melatonin (10 mg kg−1 daily, i.p. was administered from the induction of diabetes and continued for up to 12 weeks, after which the animals were sacrificed and retinal samples were collected. The retina of diabetic rats showed depletion of glutathione and downregulation of glutamate cysteine ligase (GCL. Melatonin significantly upregulated GCL by retaining Nrf2 in the nucleus and stimulating Akt phosphorylation. The production of proinflammatory cytokines and proteins, including interleukin 1β, TNF-α, and inducible nitric oxide synthase (iNOS, was inhibited by melatonin through the NF-κB pathway. At 12 weeks, melatonin prevented the significant decrease in the ERG a- and b-wave amplitudes under the diabetic condition. Our results suggest potent protective functions of melatonin in diabetic retinopathy. In addition to being a direct antioxidant, melatonin can exert receptor-mediated signaling effects to attenuate inflammation and oxidative stress of the retina.

  6. Forward current enhanced elimination of the radiation induced boron-oxygen complex in silicon n+-p diodes

    CERN Document Server

    Makarenko, L F; Yakushevich, H S; Moll, M; Pintilie, I

    2014-01-01

    Using forward current injection with densities in the range 15-30A/cm(2) we can effectively eliminate the radiation-induced boron-oxygen complex, which is the main compensating center in irradiated Si solar cells. It was found that for a given forward current density the elimination rate is decreasing with increasing irradiation dose. Additionally, some evidences have been obtained on the negative-U properties of the radiation-induced boron-oxygen complex.

  7. Endoplasmic reticulum stress in pathogenesis of diabetic retinopathy and effect of calcium dobesilate

    Institute of Scientific and Technical Information of China (English)

    Yu-Min Gui; Ming Zhao; Jie Ding

    2016-01-01

    Objective:To study the mechanism of endoplasmic reticulum stress in the pathogenesis of diabetic retinopathy and effect of calcium dobesilate.Methods:A total of 120 diabetic retinopathy patients treated in our hospital from January 2010 to September 2015 were enrolled in this article. The serum endoplasmic reticulum stress protein and interleukin protein expression levels were analyzed before and after calcium dobesilate treatment. A total of 55 cases of healthy subjects receiving physical examination in our hospital during the same period were taken as control group.Results:Serum endoplasmic reticulum stress proteins PERK, CHOP and IRE as well as interleukin proteins IL1, IL2, IL6 and IL10 expression significantly increased, serum MDA level significantly increased while SOD, CAT and GSHpx levels significantly decreased in diabetic retinopathy patients, and compared with control group (P<0.01); after calcium dobesilate treatment, above factors were significantly restored (P<0.01).Conclusions: Diabetic retinopathy is closely related to endoplasmic reticulum stress and calcium dobesilate treatment may improve diabetic retinopathy by inhibiting endoplasmic reticulum stress.

  8. Diabetic retinopathy: could the alpha-1 antitrypsin be a therapeutic option?

    Directory of Open Access Journals (Sweden)

    Gustavo Ortiz

    2014-01-01

    Full Text Available Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF to induce the angiogenesis process. Alpha-1 antitrypsin (AAT is the most important circulating inhibitor of serine proteases (SERPIN. Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3 and plasminogen activator (PAI. AAT modulates the effect of protease-activated receptors (PARs during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs. Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO by nitric oxide sintase (NOS inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.

  9. The North Jutland County Diabetic Retinopathy Study (NCDRS): population characteristics

    DEFF Research Database (Denmark)

    Knudsen, Lars Loumann; Lervang, Hans-Henrik; Lundbye-Christensen, Søren

    2006-01-01

    Background: Several population-based studies have reported blood glucose levels and blood pressure to be risk factors for the development of diabetic retinopathy. These studies were initiated more than two decades ago and may therefore reflect the treatment and population composition of a previous...... era, suggesting new studies of the present population with diabetes. Aim and methods: This cross-section study included 656 people with type 1 diabetes and 328 with type 2 diabetes. Crude prevalence rates of proliferative diabetic retinopathy, clinically significant macular oedema and several specific...... retinal lesions were assessed, together with their association to a simplified and internationally approved retinal grading. Results: The point prevalence of proliferative retinopathy was found to be 0.8% and 0.3% for type 1 and type 2 diabetes. Equivalent prevalence rates of clinically significant...

  10. Relation between fasting glucose and retinopathy for diagnosis of diabetes: three population-based cross-sectional studies.

    Science.gov (United States)

    Wong, Tien Y; Liew, Gerald; Tapp, Robyn J; Schmidt, Maria Inês; Wang, Jie Jin; Mitchell, Paul; Klein, Ronald; Klein, Barbara E K; Zimmet, Paul; Shaw, Jonathan

    2008-03-01

    The WHO and American Diabetes Association criteria for diagnosing diabetes mellitus assume the presence of a glycaemic threshold with high sensitivity for identifying retinopathy. However, this assumption is based on data from three previous studies that had important limitations in detecting retinopathy. We aimed to provide updated data for the relation between fasting plasma glucose (FPG) and retinopathy, and to assess the diagnostic accuracy of current FPG thresholds in identifying both prevalent and incident retinopathy. We examined the data from three cross-sectional adult populations: those in the Blue Mountains Eye Study (BMES, Australia, n=3162), the Australian Diabetes, Obesity and Lifestyle Study (AusDiab, Australia, n=2182), and the Multi-Ethnic Study of Atherosclerosis (MESA, USA, n=6079). Retinopathy was diagnosed from multiple retinal photographs of each eye, and graded according to the modified Airlie House Classification system. Plasma glucose concentrations were measured from fasting venous blood samples. The overall prevalence of retinopathy was 11.5% in BMES (95% CI 10.4-12.6%), 9.6% in AusDiab (8.4-10.9), and 15.8% in MESA (14.9-16.7). However, we found inconsistent evidence of a uniform glycaemic threshold for prevalent and incident retinopathy, with analyses suggesting a continuous relation. The widely used diabetes FPG cutoff of 7.0 mmol/L or higher had sensitivity less than 40% (range 14.8-39.1) for detecting retinopathy, with specificity between 80.8% and 95.8%. The area under receiver operating characteristic curves for FPG and retinopathy was low and ranged from 0.56 to 0.61. We saw no evidence of a clear and consistent glycaemic threshold for the presence or incidence of retinopathy across different populations. The current FPG cutoff of 7.0 mmol/L used to diagnose diabetes did not accurately identify people with and without retinopathy. These findings suggest that the criteria for diagnosing diabetes could need reassessment.

  11. Scotoma analysis of 10–2 visual field testing with a red target in screening for hydroxychloroquine retinopathy

    Directory of Open Access Journals (Sweden)

    Browning DJ

    2015-08-01

    Full Text Available David J Browning, Chong LeeDepartment of Ophthalmology, Charlotte Eye, Ear, Nose and Throat Associates, Charlotte, NC, USAObjective: To quantify the variability of scotomas detected by 10–2 visual field (VF testing with a red target in patients taking hydroxychloroquine without and with retinopathy.Design: Retrospective review of clinical charts and VFs.Methods: Twenty-four patients taking hydroxychloroquine without retinopathy, and eight patients taking hydroxychloroquine with retinopathy were tested in this study. Retinopathy was defined by annular scotomas on 10–2 VF testing with corroborative spectral domain optical coherence tomographic outer retinal changes and multifocal electroretinographic changes leading to cessation of hydroxychloroquine or chloroquine. Location and depth of scotoma points on 10–2 VF testing were recorded and their fates followed in serial, reliable 10–2 VFs performed with a red target over time. The main outcome measures for this study were the number of scotoma points and locations, percentage of persistent scotoma points, size of scotomas, location of scotomas, and percentage of scotomas deepening. Results: A median of 3, interquartile range (IQR (2, 5, scotoma points per VF occurred in patients without retinopathy. A median of 86%, IQR (77, 100, of these resolved on the subsequent field. For patients with retinopathy, a median of 50%, IQR (46, 79, resolved, a difference compared to patients without retinopathy that was significant (P=0.0158. The median percentage of scotoma points in the zone from 2° to 8° from fixation in eyes with retinopathy was 72%, IQR (54, 100, compared to 49%, IQR (40, 54, in eyes without retinopathy (P=0.0069. The number of persistent scotoma locations at the last visit was higher in eyes with retinopathy: 3, IQR (1, 3, versus 0, IQR (0, 1, in patients without retinopathy, P=0.0156.Conclusion: Point scotomas are common and variable in 10–2 VF testing with a red target for

  12. Prevalence and outcomes of laser treatment of aggressive posterior retinopathy of prematurity.

    Science.gov (United States)

    Gunn, David J; Cartwright, David W; Gole, Glen A

    2014-07-01

    To describe outcomes in a cohort of extremely premature infants treated for aggressive posterior retinopathy of prematurity by diode laser panretinal photocoagulation. Retrospective study. Fifteen eyes in eight infants. A review was carried out on infants between 23 and 25.6 weeks gestational age admitted to The Royal Brisbane and Women's Hospital neonatal intensive care unit between 1992 and 2009. Success of treatment, visual and refractive outcomes. Five hundred fifty-four infants were admitted to neonatal intensive care unit, 373 survived till screening, and 304 had retinopathy of prematurity. Sixty-six infants required treatment, and eight of these had aggressive posterior retinopathy of prematurity (2.5% of all infants with retinopathy of prematurity). Mean gestational age was 24.2 weeks, mean birthweight was 634 g, and treatment occurred at mean 34.1 weeks post-menstrual age. The mean total number of burns per eye was 2967. Five of 15 treated eyes required retreatment. Two patients subsequently died of unrelated causes. Regression occurred in 9 of 11 remaining eyes; one eye progressed to stage 4b and another to stage 5 retinopathy of prematurity. Vitrectomy was performed in two eyes. Five eyes had 6/12 vision, one had 3/60, and three had no perception of light. Of the remaining two eyes, one had good fixation and the other had poor fixation. Despite good structural outcomes, visual outcomes for conventional laser treatment of aggressive posterior retinopathy of prematurity are poor. © 2013 Royal Australian and New Zealand College of Ophthalmologists.

  13. Visual acuity at 10 years in Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) study eyes: effect of retinal residua of retinopathy of prematurity.

    Science.gov (United States)

    Dobson, Velma; Quinn, Graham E; Summers, C Gail; Hardy, Robert J; Tung, Betty

    2006-02-01

    To describe recognition (letter) acuity at age 10 years in eyes with and without retinal residua of retinopathy of prematurity (ROP). Presence and severity of ROP residua were documented by a study ophthalmologist. Masked testers measured monocular recognition visual acuity (Early Treatment of Diabetic Retinopathy Study) when the children were 10 years old. Two hundred forty-seven of 255 surviving Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) randomized trial patients participated. A reference group of 102 of 104 Philadelphia-based CRYO-ROP study participants who did not develop ROP was also tested. More severe retinal residua were associated with worse visual acuity, regardless of whether retinal ablation was performed to treat the severe acute-phase ROP. However, within each ROP residua category, there was a wide range of visual acuity results. This is the first report of the relation between visual acuity (Early Treatment of Diabetic Retinopathy Study charts) and structural abnormalities related to ROP in a large group of eyes that developed threshold ROP in the perinatal period. Visual deficits are greater in eyes with more severe retinal residua than in eyes with mild or no residua. However, severity of ROP residua does not predict the visual acuity of an individual eye because within a single residua category, acuity may range from near normal to blind.

  14. Prevalence of systemic co-morbidities in patients with various grades of diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Pradeep Venkatesh

    2014-01-01

    Full Text Available Background & objectives : Though diabetes affects multiple organs, most studies highlight the occurence of only one complication in isolation. We conducted a hospital-based study to estimate the co-existence of significant systemic co-morbid conditions in patients with varying grades of diabetic retinopathy. Methods : A total of 170 consecutive patients with diabetic retinopathy were prospectively recruited for the study between June 2009 to June 2010 at a tertiary care eye centre in north India. Retinopathy was graded by fundus biomicroscopy and fundus photography and classified into three categories (mild-moderate nonproliferative retinopathy, proliferative retinopathy requiring only laser and proliferative retinopathy requiring surgery. Nephropathy was classified by calculating the six variable estimated glomerular filtration rate (eGFR for all patients. Nerve conduction studies and clinical assessment were used to determine presence of neuropathy. Co-existence of macrovascular disease and peripheral vascular disease was also ascertained. Results : The percentages of patients with overt nephropathy in the three groups were 19.2, 38.0 and 41.2, respectively. Significant linear trends were observed for serum creatinine (P=0.004, albumin (P=0.017 and eGFR (P=0.030. A higher per cent had abnormal nerve conduction on electrophysiology than that diagnosed clinically (65.4 vs. 44.2, 76.0 vs. 40.0 and 64.8 vs. 48.6, respectively. The odds ratio (95% CI for co-existence of nephropathy, neuropathy, CVA (cerebrovascular accidents and PVD (peripheral vascular disease was 2.9, 0.9, 4.8 and 3.5, respectively. Independent of retinopathy severity, patients with clinically significant macular oedema (CSME had a higher percentage of nephropathy ( p0 < 0.005. Interpretation & conclusions : The co-existence of overt nephropathy, nerve conduction based neuropathy and macrovascular co-morbidity in patients with early grades of diabetic retinopathy was significant

  15. Risk factors associated with diabetic retinopathy among type 2 diabetes patients at teaching hospital in Malaysia.

    Science.gov (United States)

    Abougalambou, Salwa Selim Ibrahim; Abougalambou, Ayman S

    2015-01-01

    Diabetic retinopathy (DR) is the leading cause of blindness in the United States and it is the leading cause of new cases of blindness in adults aged 20-74. It is estimated that about 20% of patients with type 2 DM have evidence of diabetic retinopathy at diagnosis with diabetes. To evaluate the prevalence of DR and to determine risk factors related to diabetic retinopathy among type 2 diabetes patients attending endocrinology clinics at Hospital Universiti Sains Malaysia (HUSM). The study design was observational prospective longitudinal follow-up study, the study was conducted with sample of 1077 type 2 diabetes mellitus outpatient recruited via attended the diabetes clinics at HUSM. Diagnosis of retinopathy is based on finding the diagnostic signs of retinopathy on eye exams by fundoscopy. Logistic regression analysis was used to assess the independent variables that affect the development of retinopathy. The prevalence of retinopathy was 39.3%. It has been noticed from this study findings, that the progression of retinopathy is been influenced by five independent risk factors such as duration of diabetes, presence neuropathy, total cholesterol at second and third visit and createnine clearance. DR is highly prevalent among type 2 DM. The progression of retinopathy is been influenced by five independent risk factors such as duration of diabetes, presence neuropathy, total cholesterol at second and third visit and createnine clearance. DR is a serious diabetic complication and public health strategies are required in order to reduce its risk factors and decrease its prevalence. Copyright © 2014 Diabetes India. Published by Elsevier Ltd. All rights reserved.

  16. Proteomic analysis of plasma proteins in diabetic retinopathy patients by two dimensional electrophoresis and MALDI-Tof-MS.

    Science.gov (United States)

    Gopalakrishnan, Vidhya; Purushothaman, Parthiban; Bhaskar, Anusha

    2015-01-01

    Diabetic retinopathy is a highly specific vascular complication of diabetes mellitus and progresses from mild non-proliferative abnormalities characterized by increased vascular permeability to moderate and severe proliferative diabetic retinopathy characterized by the growth of blood vessels on the retina. The aim of the study was to identify the differentially expressed proteins in diabetic retinopathy using two-dimensional electrophoresis. Blood sample was drawn from subjects with diabetes mellitus (without retinopathy) who served as controls and patients with diabetic retinopathy in tubes containing EDTA as anticoagulant. Albumin and immunoglobulin IgG collectively removed to enrich proteins of lower abundance. 2de was carried out to see if there are any differentially expressed proteins. Approximately 48 and 61 spots were identified in control and diabetic retinopathy respectively, of which three protein spots RBP1 (retinol-binding protein 1), NUD10 (Diphosphoinositol polyphosphohydrolase 3 alpha), NGB (neuroglobin) were down regulated and HBG2 (hemoglobin) and BY55 (CD 160 antigen) were upregulated in diabetic retinopathy. These five protein spots were excised and were subjected to in-gel tryptic digestion, and their identities were determined by ultraflex MALDI-TOF-MS. We report a comprehensive patient-based plasma proteomic approach to the identification of potential biomarkers for diabetic retinopathy screening and detection. We identified 5 different proteins that were differentially expressed in the plasma of control diabetic patients (without retinopathy). Among these five proteins the expression of neuroglobin (NGB) protein varied significantly and may be a potential biomarker in diabetic retinopathy. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Effect of oxygen-breathing during a decompression-stop on bubble-induced platelet activation after an open-sea air dive: oxygen-stop decompression.

    Science.gov (United States)

    Pontier, J-M; Lambrechts, K

    2014-06-01

    We highlighted a relationship between decompression-induced bubble formation and platelet micro-particle (PMP) release after a scuba air-dive. It is known that decompression protocol using oxygen-stop accelerates the washout of nitrogen loaded in tissues. The aim was to study the effect of oxygen deco-stop on bubble formation and cell-derived MP release. Healthy experienced divers performed two scuba-air dives to 30 msw for 30 min, one with an air deco-stop and a second with 100% oxygen deco-stop at 3 msw for 9 min. Bubble grades were monitored with ultrasound and converted to the Kisman integrated severity score (KISS). Blood samples for cell-derived micro-particle analysis (AnnexinV for PMP and CD31 for endothelial MP) were taken 1 h before and after each dive. Mean KISS bubble score was significantly lower after the dive with oxygen-decompression stop, compared to the dive with air-decompression stop (4.3 ± 7.3 vs. 32.7 ± 19.9, p air-breathing decompression stop, we observed an increase of the post-dive mean values of PMP (753 ± 245 vs. 381 ± 191 ng/μl, p = 0.003) but no significant change in the oxygen-stop decompression dive (329 ± 215 vs. 381 +/191 ng/μl, p = 0.2). For the post-dive mean values of endothelial MP, there was no significant difference between both the dives. The Oxygen breathing during decompression has a beneficial effect on bubble formation accelerating the washout of nitrogen loaded in tissues. Secondary oxygen-decompression stop could reduce bubble-induced platelet activation and the pro-coagulant activity of PMP release preventing the thrombotic event in the pathogenesis of decompression sickness.

  18. EPIDEMIOLOGICAL STUDY OF DIABETIC RETINOPATHY IN DIABETES MELLITUS PATIENTS IN TERTIARY CARE CENTRE

    Directory of Open Access Journals (Sweden)

    Bhaskar

    2016-02-01

    Full Text Available OBJECTIVE The study objective was to examine the effect of glycaemic control and variations on the incidence and progression of diabetic retinopathy (DR among the diabetes mellitus patients visiting Medicine and Ophthalmology OPD Sapthagiri Medical college, Bangalore. MATERIALS AND METHODS 10 patients with type 1 diabetes mellitus, and 70 persons with type 2 diabetes mellitus, visiting the Medicine OPD of Sapthagiri Medical College and referred to Ophthalmology department of the above to detect the Diabetic Retinopathy changes in a diabetes mellitus management programme conducted for 3 months in Bangalore, participated in the study. Patients who were followed up for 6 months the same above were also included in the study. Analyses were conducted to assess the relationship between the risk factors, incidence and progression of Diabetic Retinopathy among Diabetes Mellitus patients and management. MAIN OUTCOME MEASURES To determine the risk factors associated with it, stage of retinopathy diagnosed at presentation, management of it, and final visual outcome. The prevention is by strict glycaemic control, prompt use of anti-diabetic drugs and regular exercises. These included age and gender-adjusted prevalence of diabetes and diabetic retinopathy, 1 and correlation of prevalence with history-based risk factors. RESULTS The three months cumulative incidence of DR was 58 %in type I diabetes mellitus and 42 % among type II Diabetes mellitus. After controlling for known risk factors for DR,1 a high baseline haemoglobin A1c (HbA1c, ethnicity, age, type of diabetes mellitus, duration were associated with the incidence of referable DR in patients with type 1 and type 2 diabetes mellitus. The age- and gender-adjusted prevalence rate of diabetes in urban Bangalore 28.2% (95% confidence interval [CI], and the prevalence of diabetic retinopathy in general population was 3.5% (95% CI. The prevalence of diabetic retinopathy in the population with diabetes

  19. Activation-induced resetting of cerebral oxygen and glucose uptake in the rat

    DEFF Research Database (Denmark)

    Madsen, P L; Linde, R; Hasselbalch, S G

    1998-01-01

    In the clinical setting it has been shown that activation will increase cerebral glucose uptake in excess of cerebral oxygen uptake. To study this phenomenon further, this study presents an experimental setup that enables precise determination of the ratio between cerebral uptake of glucose...... and oxygen in the awake rat. Global CBF was measured by the Kety-Schmidt technique, and the ratio between cerebral uptake rates for oxygen, glucose, and lactate was calculated from cerebral arterial-venous differences. During baseline conditions, rats were kept in a closed box designed to minimize...... interference. During baseline conditions CBF was 1.08 +/- 0.25 mL x g(-1) x minute(-1), and the cerebral oxygen to glucose uptake ratio was 5.5. Activation was induced by opening the sheltering box for 6 minutes. Activation increased CBF to 1.81 mL x g(-1) x minute(-1). During activation cerebral glucose...

  20. Is hypertension a major independent risk factor for retinopathy in type 1 diabetes?

    DEFF Research Database (Denmark)

    Nørgaard, K; Feldt-Rasmussen, B; Deckert, T

    1991-01-01

    Hypertension is an established risk factor for retinopathy. Whether it is an independent risk factor or acts only by association with nephropathy is not known. Therefore, we studied 273 Type 1 diabetic patients. They were divided into four groups. Group 1 (n = 55) were normotensive...... and normoalbuminuric, group 2 (n = 51) had hypertension but were normoalbuminuric, group 3 (n = 33) had nephropathy but were normotensive, and group 4 (n = 134) had nephropathy and hypertension. Hypertensive patients with normoalbuminuria (blood pressure 146 +/- 19 (+/-SD)/87 +/- 12 mmHg) had the same prevalence...... of retinopathy as normoalbuminuric normotensive patients (123 +/- 12/75 +/- 5 mmHg). Hypertensive nephropathic patients (blood pressure 147 +/- 18/87 +/- 8 mmHg) had more retinopathy than hypertensive normoalbuminuric patients despite similar blood pressure (normal retina/advanced retinopathy: 3%/73% vs 46...

  1. Plasma E-selectin levels can play a role in the development of diabetic retinopathy.

    Science.gov (United States)

    Kasza, Márta; Meleg, J; Vardai, J; Nagy, B; Szalai, E; Damjanovich, J; Csutak, A; Ujhelyi, B; Nagy, V

    2017-01-01

    Diabetic retinopathy is one of the leading causes of blindness. There are several risk factors, such as the duration of diabetes or glycemic control of the patient; however, several biochemical factors also alter the process. Our aim was to investigate the role of soluble E-selectin in the formation of diabetic retinopathy. Fifty-seven patients (37 female and 20 male, aged 61.71 ± 12.31 years) and 14 healthy control subjects (ten female and four male, aged 63.06 ± 10.46 years) were enrolled in the study. We measured the soluble E-selectin level in the plasma of patients by ELISA. All patients underwent careful ophthalmological examination, including ophthalmoscopy and color fundus photography, while diabetic retinopathy grading was performed in line with the 2012 classification of the American Academy of Ophthalmology (AAO). The soluble E-selectin level was significantly higher in patients with diabetes compared to controls (32.95 ng/ml vs. 26.55 ng/ml, p = 0.03). Dividing patients into groups by the presence of retinopathy, the E-selectin level was also significantly higher in the retinopathy group (p diabetic patients by the severity of retinopathy (groups A, B, and C, by the guidelines of the AAO), however, we did not find any significant difference in soluble E-selectin levels, although it tended to be higher in group B. An elevated E-selectin level can play a role in the development of diabetic retinopathy, but it does not seem to alter disease severity. However, glycemic control and the reduction of cardiovascular risk factors may also alter the level of E-selectin that might play a role in the prevention of diabetic retinopathy.

  2. A degenerative retinal process in HIV-associated non-infectious retinopathy.

    Science.gov (United States)

    Kozak, Igor; Sasik, Roman; Freeman, William R; Sprague, L James; Gomez, Maria Laura; Cheng, Lingyun; El-Emam, Sharif; Mojana, Francesca; Bartsch, Dirk-Uwe; Bosten, Jenny; Ayyagari, Radha; Hardiman, Gary

    2013-01-01

    HIV retinopathy is the most common non-infectious complication in the eyes of HIV-positive individuals. Oncotic lesions in the retinal nerve fiber layer, referred to as cotton wool spots (CWS), and intraretinal (IR) hemorrhages are frequently observed but are not unique to this pathology. HIV-positive patients have impaired color vision and contrast sensitivity, which worsens with age. Evidence of inner-retinal lesions and damage have been documented ophthalmoscopically, however their long term structural effect has not been investigated. It has been hypothesized that they may be partially responsible for loss of visual function and visual field. In this study we utilized clinical data, retinal imaging and transcriptomics approaches to comprehensively interrogate non-infectious HIV retinopathy. The methods employed encompassed clinical examinations, fundus photography, indirect ophthalmoscopy, Farmsworth-Munsell 100 hue discrimination testing and Illumina BeadChip analyses. Here we show that changes in the outer retina, specifically in the retinal pigment epithelium (RPE) and photoreceptor outer segments (POS) contribute to vision changes in non-infectious HIV retinopathy. We find that in HIV-positive retinae there is an induction of rhodopsin and other transcripts (including PDE6A, PDE6B, PDE6G, CNGA1, CNGB1, CRX, NRL) involved in visual transduction, as well as structural components of the rod photoreceptors (ABCA4 and ROM1). This is consistent with an increased rate of renewal of rod outer segments induced via increased phagocytosis by HIV-infected RPE previously reported in culture. Cone-specific transcripts (OPN1SW, OPN1LW, PDE6C, PDE6H and GRK7) are uniformly downregulated in HIV positive retina, likely due to a partial loss of cone photoreceptors. Active cotton wool spots and intraretinal hemorrhages (IRH) may not affect photoreceptors directly and the interaction of photoreceptors with the aging RPE may be the key to the progressive vision changes in HIV

  3. Effect of hypolimnetic oxygenation on oxygen depletion rates in two water-supply reservoirs.

    Science.gov (United States)

    Gantzer, Paul A; Bryant, Lee D; Little, John C

    2009-04-01

    Oxygenation systems, such as bubble-plume diffusers, are used to improve water quality by replenishing dissolved oxygen (DO) in the hypolimnia of water-supply reservoirs. The diffusers induce circulation and mixing, which helps distribute DO throughout the hypolimnion. Mixing, however, has also been observed to increase hypolimnetic oxygen demand (HOD) during system operation, thus accelerating oxygen depletion. Two water-supply reservoirs (Spring Hollow Reservoir (SHR) and Carvins Cove Reservoir (CCR)) that employ linear bubble-plume diffusers were studied to quantify diffuser effects on HOD. A recently validated plume model was used to predict oxygen addition rates. The results were used together with observed oxygen accumulation rates to evaluate HOD over a wide range of applied gas flow rates. Plume-induced mixing correlated well with applied gas flow rate and was observed to increase HOD. Linear relationships between applied gas flow rate and HOD were found for both SHR and CCR. HOD was also observed to be independent of bulk hypolimnion oxygen concentration, indicating that HOD is controlled by induced mixing. Despite transient increases in HOD, oxygenation caused an overall decrease in background HOD, as well as a decrease in induced HOD during diffuser operation, over several years. This suggests that the residual or background oxygen demand decreases from one year to the next. Despite diffuser-induced increases in HOD, hypolimnetic oxygenation remains a viable method for replenishing DO in thermally-stratified water-supply reservoirs such as SHR and CCR.

  4. Singlet oxygen treatment of tumor cells triggers extracellular singlet oxygen generation, catalase inactivation and reactivation of intercellular apoptosis-inducing signaling.

    Science.gov (United States)

    Riethmüller, Michaela; Burger, Nils; Bauer, Georg

    2015-12-01

    Intracellular singlet oxygen generation in photofrin-loaded cells caused cell death without discrimination between nonmalignant and malignant cells. In contrast, extracellular singlet oxygen generation caused apoptosis induction selectively in tumor cells through singlet oxygen-mediated inactivation of tumor cell protective catalase and subsequent reactivation of intercellular ROS-mediated apoptosis signaling through the HOCl and the NO/peroxynitrite signaling pathway. Singlet oxygen generation by extracellular photofrin alone was, however, not sufficient for optimal direct inactivation of catalase, but needed to trigger the generation of cell-derived extracellular singlet oxygen through the interaction between H2O2 and peroxynitrite. Thereby, formation of peroxynitrous acid, generation of hydroxyl radicals and formation of perhydroxyl radicals (HO2(.)) through hydroxyl radical/H2O2 interaction seemed to be required as intermediate steps. This amplificatory mechanism led to the formation of singlet oxygen at a sufficiently high concentration for optimal inactivation of membrane-associated catalase. At low initial concentrations of singlet oxygen, an additional amplification step needed to be activated. It depended on singlet oxygen-dependent activation of the FAS receptor and caspase-8, followed by caspase-8-mediated enhancement of NOX activity. The biochemical mechanisms described here might be considered as promising principle for the development of novel approaches in tumor therapy that specifically direct membrane-associated catalase of tumor cells and thus utilize tumor cell-specific apoptosis-inducing ROS signaling. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Development of a Deep Learning Algorithm for Automatic Diagnosis of Diabetic Retinopathy.

    Science.gov (United States)

    Raju, Manoj; Pagidimarri, Venkatesh; Barreto, Ryan; Kadam, Amrit; Kasivajjala, Vamsichandra; Aswath, Arun

    2017-01-01

    This paper mainly focuses on the deep learning application in classifying the stage of diabetic retinopathy and detecting the laterality of the eye using funduscopic images. Diabetic retinopathy is a chronic, progressive, sight-threatening disease of the retinal blood vessels. Ophthalmologists diagnose diabetic retinopathy through early funduscopic screening. Normally, there is a time delay in reporting and intervention, apart from the financial cost and risk of blindness associated with it. Using a convolutional neural network based approach for automatic diagnosis of diabetic retinopathy, we trained the prediction network on the publicly available Kaggle dataset. Approximately 35,000 images were used to train the network, which observed a sensitivity of 80.28% and a specificity of 92.29% on the validation dataset of ~53,000 images. Using 8,810 images, the network was trained for detecting the laterality of the eye and observed an accuracy of 93.28% on the validation set of 8,816 images.

  6. Correlation between glycemic excursion by CGMS and diabetic retinopathy among Type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Pu Li; Ji Ning; Zhu Wei

    2011-01-01

    Objective: To investigate correlation between glycemic excursion by CGMS and diabetic retinopathy among type 2 diabetes mellitus. Methods: Used continuous glucose monitoring system (CGMS) to monitoring glycemic excursion within a day of twenty four patients with type 2 diabetes mellitus, and inspect fundus photography, correlation was analyzed. Results: Glycemic excursion might reveal the risk for diabetic retinopathy better than HbA1c does. Conclusion: Diabetic retinopathy may correlate with glycemic excursion. (authors)

  7. Screening for diabetic retinopathy in rural area using single-field, digital fundus images.

    Science.gov (United States)

    Ruamviboonsuk, Paisan; Wongcumchang, Nattapon; Surawongsin, Pattamaporn; Panyawatananukul, Ekchai; Tiensuwan, Montip

    2005-02-01

    To evaluate the practicability of using single-field, 2.3 million-pixel, digital fundus images for screening of diabetic retinopathy in rural areas. All diabetic patients who regularly attended the diabetic clinic at Kabcheang Community Hospital, located at 15 kilometers from the Thailand-Cambodia border, were appointed to the hospital for a 3-day diabetic retinopathy screening programme. The fundi of all patients were captured in single-field, 45 degrees, 2.3 million-pixel images using nonmydriatic digital fundus camera and then sent to a reading center in Bangkok. The fundi were also examined through dilated pupils by a retinal specialist at this hospital. The grading of diabetic retinopathy from two methods was compared for an exact agreement. The average duration of single digital fundus image capture was 2 minutes. The average file size of each image was 750 kilobytes. The average duration of single image transmission to a reading center in Bangkok via satellite was 3 minutes; via a conventional telephone line was 8 minutes. Of all 150 patients, 130 were assessed for an agreement between dilated fundus examination and digital fundus images in diagnosis of diabetic retinopathy. The exact agreement was 0.87, the weighted kappa statistics was 0.74. The sensitivity of digital fundus images in detecting diabetic retinopathy was 80%, the specificity was 96%. For diabetic macular edema the exact agreement was 0.97, the weighted kappa was 0.43, the sensitivity was 43%, and the specificity was 100%. The image capture of the nonmydriatic digital fundus camera is suitable for screening of diabetic retinopathy and single-field digital fundus images are potentially acceptable tools for the screening. The real-time image transmission via telephone lines to remote reading center, however, may not be practical for routine diabetic retinopathy screening in rural areas.

  8. Sex differences in risk factors for retinopathy in non-diabetic men and women: the Tromsø Eye Study.

    Science.gov (United States)

    Bertelsen, Geir; Peto, Tunde; Lindekleiv, Haakon; Schirmer, Henrik; Solbu, Marit D; Toft, Ingrid; Sjølie, Anne Katrin; Njølstad, Inger

    2014-06-01

      To determine the prevalence and risk factors for retinopathy in a nondiabetic population.   The study population included 5869 participants without diabetes aged 38-87 years from the Tromsø Eye Study, a substudy of the population-based Tromsø Study in Norway. Retinal images from both eyes were graded for retinopathy. We collected data on risk factors from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews. The cross-sectional relationship between potential risk factors and retinopathy was assessed using logistic regression analysis.   The overall prevalence of retinopathy was 14.8%. Men had a higher prevalence of retinopathy compared with women (15.9% versus 14.0%, p=0.04). In men, retinopathy was associated with hypertension (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.24-2.04) and HbA1c (OR per %, 1.41; 95% CI, 1.01-1.96). In women, retinopathy was associated with age (OR per 10 years, 1.32; 95% CI, 1.14-1.52), log-transformed urinary albumin excretion (OR per log unit, 1.46; 95% CI, 1.14-1.87) and hypertension (OR, 1.36; 95% CI, 1.08-1.71). In women, retinopathy was associated with very low levels of urinary albumin excretion (urinary albumin/creatinine ratio >0.43 mg/mmol).   This study confirms results from previous studies on the strong association between blood pressure and retinopathy. A novel finding is the sex differences in risk factors for retinopathy, suggesting a sex difference in the pathogenesis leading to retinopathy. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  9. Automatic screening and classification of diabetic retinopathy and maculopathy using fuzzy image processing.

    Science.gov (United States)

    Rahim, Sarni Suhaila; Palade, Vasile; Shuttleworth, James; Jayne, Chrisina

    2016-12-01

    Digital retinal imaging is a challenging screening method for which effective, robust and cost-effective approaches are still to be developed. Regular screening for diabetic retinopathy and diabetic maculopathy diseases is necessary in order to identify the group at risk of visual impairment. This paper presents a novel automatic detection of diabetic retinopathy and maculopathy in eye fundus images by employing fuzzy image processing techniques. The paper first introduces the existing systems for diabetic retinopathy screening, with an emphasis on the maculopathy detection methods. The proposed medical decision support system consists of four parts, namely: image acquisition, image preprocessing including four retinal structures localisation, feature extraction and the classification of diabetic retinopathy and maculopathy. A combination of fuzzy image processing techniques, the Circular Hough Transform and several feature extraction methods are implemented in the proposed system. The paper also presents a novel technique for the macula region localisation in order to detect the maculopathy. In addition to the proposed detection system, the paper highlights a novel online dataset and it presents the dataset collection, the expert diagnosis process and the advantages of our online database compared to other public eye fundus image databases for diabetic retinopathy purposes.

  10. INFORMATIVITY OF SPECTRAL OPTICAL COHERENT TOMOGRAPHY IN AGGRESSIVE POSTERIOR RETINOPATHY OF PREMATURITY

    Directory of Open Access Journals (Sweden)

    A. V. Tereshchenko

    2017-01-01

    Full Text Available The purpose: to evaluate the informativity of optical coherence tomography in patients with aggressive posterior retinopathy of prematurity. Patients and methods. spectral optical coherence tomography using portable device iVue-100 with a removable camera (Optovue, USA was held in 32 children (64 eyes with aggressive posterior retinopathy of prematurity with a gestational period 26–31 week. Results. Children with aggressive posterior retinopathy of prematurity at the stage of early clinical manifestations, in addition to the indication that the immaturity of the retina, according to the spectral optical coherence tomography revealed only a few areas of epiretinal proliferation, which are not visualized with a digital retinoscopy and binocular indirect ophthalmoscopy. When the process is more pronounced in children with retinopathy of prematurity aggressive rear stage manifestation already determined multiple zones epiretinal proliferation as a "mushroom" and "flake" conglomerates with rear zone hyaloid membrane had an uneven seal. Coarser structural disorders of the retina and the vitreoretinal interface have been identified in patients with advancedstage aggressive posterior retinopathy of prematurity. We determined the shaft extraretinal proliferation as a "comb", as well as portions of epiretinal proliferation on the border of vascularized and avascular retina, which tended to merge, and the formation of massive hyperreflection complexes, lifted back hyaloid membrane, which was not only uneven sealed, but in some places is stratified. Conclusion. Despite the complexity of the procedure and the complexity of its implementation, the data obtained are particularly valuable and informative because they allow to complement the clinical picture and objectify it. It helps to choose the optimal tactics and improvement of a differentiated approach to the treatment of aggressive posterior retinopathy of prematurity.

  11. Classification of diabetic retinopathy using fractal dimension analysis of eye fundus image

    Science.gov (United States)

    Safitri, Diah Wahyu; Juniati, Dwi

    2017-08-01

    Diabetes Mellitus (DM) is a metabolic disorder when pancreas produce inadequate insulin or a condition when body resist insulin action, so the blood glucose level is high. One of the most common complications of diabetes mellitus is diabetic retinopathy which can lead to a vision problem. Diabetic retinopathy can be recognized by an abnormality in eye fundus. Those abnormalities are characterized by microaneurysms, hemorrhage, hard exudate, cotton wool spots, and venous's changes. The diabetic retinopathy is classified depends on the conditions of abnormality in eye fundus, that is grade 1 if there is a microaneurysm only in the eye fundus; grade 2, if there are a microaneurysm and a hemorrhage in eye fundus; and grade 3: if there are microaneurysm, hemorrhage, and neovascularization in the eye fundus. This study proposed a method and a process of eye fundus image to classify of diabetic retinopathy using fractal analysis and K-Nearest Neighbor (KNN). The first phase was image segmentation process using green channel, CLAHE, morphological opening, matched filter, masking, and morphological opening binary image. After segmentation process, its fractal dimension was calculated using box-counting method and the values of fractal dimension were analyzed to make a classification of diabetic retinopathy. Tests carried out by used k-fold cross validation method with k=5. In each test used 10 different grade K of KNN. The accuracy of the result of this method is 89,17% with K=3 or K=4, it was the best results than others K value. Based on this results, it can be concluded that the classification of diabetic retinopathy using fractal analysis and KNN had a good performance.

  12. THE PREVENTION OF BLINDNESS AND VISUAL IMPAIRMENT IN CHILDREN WITH RETINOPATHY OF PREMATURITY

    Directory of Open Access Journals (Sweden)

    V. V. Neroev

    2015-01-01

    Full Text Available The system of blindness prevention and visual impairment in children with retinopathy of prematurity is a multidisciplinary medical problem, and includes the prevention of the preterm birth, the correction of terms of caring for premature babies, early detection, monitoring, and treatment of retinopathy of prematurity, as well as the organization of the long clinical supervision. Patients with retinopathy of prematurity need a comprehensive approach to the prevention of the visual impairment in order to ensure high functional outcomes and improve their quality of life. 

  13. Semaglutide, reduction in HbA1c and the risk of diabetic retinopathy

    DEFF Research Database (Denmark)

    Vilsbøll, Tina; Bain, Stephen C; Leiter, Lawrence A

    2018-01-01

    AIMS: To evaluate diabetic retinopathy data from across the SUSTAIN clinical trial programme. MATERIALS AND METHODS: The SUSTAIN clinical trial programme evaluated the efficacy and safety of semaglutide, a glucagon-like peptide-1 analogue, for the treatment of type 2 diabetes (T2D). In SUSTAIN 6...... - a 2-year, preapproval cardiovascular outcomes trial - semaglutide was associated with a significant increase in the risk of diabetic retinopathy complications (DRC) versus placebo. Diabetic retinopathy (DR) data from across the SUSTAIN trials were evaluated and post hoc analyses of the SUSTAIN 6 data...

  14. Both Autocrine Signaling and Paracrine Signaling of HB-EGF Enhance Ocular Neovascularization.

    Science.gov (United States)

    Inoue, Yuki; Shimazawa, Masamitsu; Nakamura, Shinsuke; Takata, Shinsuke; Hashimoto, Yuhei; Izawa, Hiroshi; Masuda, Tomomi; Tsuruma, Kazuhiro; Sakaue, Tomohisa; Nakayama, Hironao; Higashiyama, Shigeki; Hara, Hideaki

    2018-01-01

    The incidence of blindness is increasing because of the increase in abnormal ocular neovascularization. Anti-VEGF (vascular endothelial growth factor) therapies have led to good results, although they are not a cure for the blindness. The purpose of this study was to determine what role HB-EGF (heparin-binding epidermal growth factor-like growth factor) plays in ocular angiogenesis. We examined the role played by HB-EGF in ocular neovascularization in 2 animal models of neovascularization: laser-induced choroidal neovascularization (CNV) and oxygen-induced retinopathy. We also studied human retinal microvascular endothelial cells in culture. Our results showed that the neovascularization was decreased in both the CNV and oxygen-induced retinopathy models in HB-EGF conditional knockout mice compared with that in wild-type mice. Moreover, the expressions of HB-EGF and VEGF were increased after laser-induced CNV and oxygen-induced retinopathy, and their expression sites were located around the neovascular areas. Exposure of human retinal microvascular endothelial cells to HB-EGF and VEGF increased their proliferation and migration, and CRM-197 (cross-reactive material-197), an HB-EGF inhibitor, decreased the HB-EGF-induced and VEGF-induced cell proliferation and migration. VEGF increased the expression of HB-EGF mRNA. VEGF-dependent activation of EGFR (epidermal growth factor receptor)/ERK1/2 (extracellular signal-regulated kinase 1/2) signaling and cell proliferation of endothelial cells required stimulation of the ADAM17 (a disintegrin and metalloprotease) and ADAM12. CRM-197 decreased the grades of the fluorescein angiograms and size of the CNV areas in marmoset monkeys. These findings suggest that HB-EGF plays an important role in the development of CNV. Therefore, further investigations of HB-EGF are needed as a potential therapeutic target in the treatment of exudative age-related macular degeneration. © 2017 American Heart Association, Inc.

  15. Relationship between mitochondrial dysfunction, oxidative stress and diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Song Yue

    2014-12-01

    Full Text Available As one of the serious complications of diabetes, diabetic retinopathy(DRhas become a main eye disease which causes blindness. The occurrence and development of DR is related to many factors. The pathogenesis is complicated, and the mechanism has not been clear. Early data suggest that the occurrence and development of DR has relations with many factors such as blood sugar level, diabetes duration and the environment. Among the factors, mitochondrial dysfunction and oxidative stress is the important mechanisms of DR and has become research focus in recent years. Consequences of mitochondrial dysfunction within cells include elevation of the rate of reactive oxygen species(ROSproduction due to damage of electron transport chain proteins, mitochondrial DNA(mtDNAdamage, and loss of metabolic capacity. Clear understanding on the mechanism of mitochondrial functional change under high sugar level and oxidative stress response in the occurrence and development of DR is of great significance on prevention and cure of DR. In this article, the development of mitochondrial metabolism and oxidative stress of DR is reviewed.

  16. Frequency of diabetic retinopathy in patients after ten years of diagnosis of type 2 diabetes mellitus

    International Nuclear Information System (INIS)

    Shaikh, M.A.; Yakta, D.E.

    2010-01-01

    Background: Diabetic retinopathy is one of the most common and serious complications of type 2 diabetes mellitus and a leading cause of blindness not only in Pakistan but also worldwide. So we conducted this study to record the frequency of diabetic retinopathy in known diabetic patients ten years after diagnosis of type 2 diabetes mellitus. Methods: The study was conducted at Liaquat University of Medical and Health Sciences, Jamshoro, Pakistan for a period of 1 year from January 2008 to January 2010. The study group comprised of 200 patients of type 2 diabetes mellitus attending the medical clinic. All patients who were diagnosed as type 2 diabetes mellitus since ten years duration were included in the study. Retinopathy was graded into background, pre proliferative and proliferative retinopathy. Type 2 diabetes was diagnosed using the WHO criteria. Statistical analysis was carried out using the SPSS-11. Results: Diabetic retinopathy was found in 25.5% of the total Type 2 patients after ten years of diagnosis, and of these 4% of patients had proliferative retinopathy. Conclusion: Type 2 diabetic patients should be screened as early as possible to prevent permanent visual loss by timely management of diabetic retinopathy because diabetes is one of most common preventable cause of blindness in the world. (author)

  17. Automatic detection of retinal exudates in fundus images of diabetic retinopathy patients

    Directory of Open Access Journals (Sweden)

    Mahsa Partovi

    2016-05-01

    Full Text Available Introduction: Diabetic retinopathy (DR is the most frequent microvascular complication of diabetes and can lead to several retinal abnormalities including microaneurysms, exudates, dot and blot hemorrhages, and cotton wool spots. Automated early detection of these abnormalities could limit the severity of the disease and assist ophthalmologists in investigating and treating the disease more efficiently. Segmentation of retinal image features provides the basis for automated assessment. In this study, exudates lesion on retinopathy retinal images was segmented by different image processing techniques. The objective of this study is detection of the exudates regions on retinal images of retinopathy patients by different image processing techniques. Methods: A total of 30 color images from retinopathy patients were selected for this study. The images were taken by Topcon TRC-50 IX mydriatic camera and saves with TIFF format with a resolution of 500 × 752 pixels. The morphological function was applied on intensity components of hue saturation intensity (HSI space. To detect the exudates regions, thresholding was performed on all images and the exudates region was segmented. To optimize the detection efficiency, the binary morphological functions were applied. Finally, the exudates regions were quantified and evaluated for further statistical purposes. Results: The average of sensitivity of 76%, specificity of 98%, and accuracy of 97% was obtained. Conclusion: The results showed that our approach can identify the exudate regions in retinopathy images.

  18. Prostate-Specific Membrane Antigen Regulation of Prostate Tumor Growth, Angiogenesis,and Integrin Signal Transduction

    Science.gov (United States)

    2012-07-01

    mothers were maintained in 75% oxygen for five days. After 2.5 days in 75% oxygen, the lactating females were replaced with surrogate dames. Mice were... harmful side effects. To avoid this possibility we treated OIR mice with a single intravitreal injection of 2-PMPA on P14 and measured avascular area three...experiments. Oxygen Induced Retinopathy (OIR) Model Seven day old mice weighing 6g or greater and their lactating mothers were maintained in 75% oxygen

  19. A Review on Recent Developments for Detection of Diabetic Retinopathy

    OpenAIRE

    Amin, Javeria; Sharif, Muhammad; Yasmin, Mussarat

    2016-01-01

    Diabetic retinopathy is caused by the retinal micro vasculature which may be formed as a result of diabetes mellitus. Blindness may appear as a result of unchecked and severe cases of diabetic retinopathy. Manual inspection of fundus images to check morphological changes in microaneurysms, exudates, blood vessels, hemorrhages, and macula is a very time-consuming and tedious work. It can be made easily with the help of computer-aided system and intervariability for the observer. In this paper,...

  20. Automated microaneurysm detection algorithms applied to diabetic retinopathy retinal images

    Directory of Open Access Journals (Sweden)

    Akara Sopharak

    2013-07-01

    Full Text Available Diabetic retinopathy is the commonest cause of blindness in working age people. It is characterised and graded by the development of retinal microaneurysms, haemorrhages and exudates. The damage caused by diabetic retinopathy can be prevented if it is treated in its early stages. Therefore, automated early detection can limit the severity of the disease, improve the follow-up management of diabetic patients and assist ophthalmologists in investigating and treating the disease more efficiently. This review focuses on microaneurysm detection as the earliest clinically localised characteristic of diabetic retinopathy, a frequently observed complication in both Type 1 and Type 2 diabetes. Algorithms used for microaneurysm detection from retinal images are reviewed. A number of features used to extract microaneurysm are summarised. Furthermore, a comparative analysis of reported methods used to automatically detect microaneurysms is presented and discussed. The performance of methods and their complexity are also discussed.

  1. Automated screening for retinopathy

    Directory of Open Access Journals (Sweden)

    A. S. Rodin

    2014-07-01

    Full Text Available Retinal pathology is a common cause of an irreversible decrease of central vision commonly found amongst senior population. Detection of the earliest signs of retinal diseases can be facilitated by viewing retinal images available from the telemedicine networks. To facilitate the process of retinal images, screening software applications based on image recognition technology are currently on the various stages of development.Purpose: To develop and implement computerized image recognition software that can be used as a decision support technologyfor retinal image screening for various types of retinopathies.Methods: The software application for the retina image recognition has been developed using C++ language. It was tested on dataset of 70 images with various types of pathological features (age related macular degeneration, chorioretinitis, central serous chorioretinopathy and diabetic retinopathy.Results: It was shown that the system can achieve a sensitivity of 73 % and specificity of 72 %.Conclusion: Automated detection of macular lesions using proposed software can significantly reduce manual grading workflow. In addition, automated detection of retinal lesions can be implemented as a clinical decision support system for telemedicine screening. It is anticipated that further development of this technology can become a part of diagnostic image analysis system for the electronic health records.

  2. Neovascularization in Purtscher's retinopathy

    Directory of Open Access Journals (Sweden)

    Chan A

    2011-11-01

    Full Text Available Annie Chan, Douglas R Fredrick, Theodore Leng Department of Ophthalmology, Byers Eye Institute at Stanford University, Stanford University School of Medicine, Stanford, CA, USA Abstract: We report a case of neovascularization secondary to Purtscher's retinopathy that showed minimal improvement with photocoagulation treatment. A 14-year-old boy with a history of cerebellar medulloblastoma presented with blurry vision and floaters after being struck by a motor vehicle while riding his bike. At presentation, visual acuity was 20/400 in his right eye and counting fingers in his left eye. Fundus examination showed disk edema, retinal whitening, and retinal hemorrhages in both eyes. Optical coherence tomography demonstrated thinning of the temporal retina and disruption of the inner segment–outer segment junction of the photoreceptor layer in the right eye and thickening and edema of the nasal macula, as well as a central foveal hyper-reflectivity, in the left eye. At the initial visit, there was no ischemia or neovascularization (NV. One month later, the patient developed NV of the disk and ischemia in the mid-periphery of the left eye. The patient underwent treatment with pan-retinal photocoagulation. The NV regressed, but visual outcome remained poor at his 5-month follow-up visit. Keywords: Purtscher's retinopathy, neovascularization, laser photocoagulation, disk edema

  3. Screening in Primary Care for Diabetic Retinopathy, Maculopathy and Visual Loss in South Africa.

    Science.gov (United States)

    Webb, Elizabeth M; Rheeder, Paul; Roux, Polla

    2016-01-01

    The aim of the study was to determine the prevalence of diabetic retinopathy, maculopathy and visual loss in primary care patients and to identify associated risk factors. We conducted a cluster randomised trial at primary care clinics in the Tshwane district in South Africa. Grades of retinopathy and maculopathy (with fundus camera) and visual acuity (Snellen chart) were assessed and, using mobile screening and teleophthalmology, clinical and biochemical testing was conducted to obtain information about glycaemic control and microvascular complications. The prevalence rates for any retinopathy, preproliferative retinopathy and proliferative retinopathy were 24.9, 19.5 and 5.5%, respectively. The prevalence rates of diabetic maculopathy, observable maculopathy and referable maculopathy were 20.8, 11.8 and 9.0%, respectively. The presence of retinopathy was associated with high body mass index, systolic blood pressure, being on insulin treatment, high HbA1c and the presence of neuropathy. High systolic blood pressure, being on insulin treatment, high HbA1c level and high low-density lipoprotein cholesterol level as well as the presence of albuminuria were significant in predicting any diabetic maculopathy. Laser photocoagulation was given to 8.3% of patients from the mobile unit and 12% of patients were referred to the nearest hospital with an outpatient eye clinic for follow-up treatment of various other eye conditions. Using the WHO categories, the study found that 78.1% of diabetes patients had normal vision, 19.3% were visually impaired and 2.2% were severely impaired or blind. High prevalence rates for diabetic retinopathy, maculopathy and visual loss were found and associations were identified. © 2016 S. Karger AG, Basel.

  4. The effect of oral acetazolamide on cystoid macular edema in hydroxychloroquine retinopathy: a case report.

    Science.gov (United States)

    Hong, Eun Hee; Ahn, Seong Joon; Lim, Han Woong; Lee, Byung Ro

    2017-07-12

    Hydroxychloroquine (HCQ) retinopathy can accompany other retinal complications such as cystoid macular edema (CME), which leads to central visual loss. We report a case of CME with HCQ retinopathy that improved with the use of oral acetazolamide, and discussed the possible mechanisms of CME in HCQ retinopathy using multimodal imaging modalities. A 62-year-old patient with systemic lupus erythematosus (SLE) and HCQ retinopathy developed bilateral CME with visual decline. Fluorescein angiography (FA) showed fluorescein leakage in the macular and midperipheral area. After treatment with oral acetazolamide (250 mg/day) for one month, CME was completely resolved, best corrected visual acuity (BCVA) improved from 20/50 to 20/25, and FA examination showed decreased dye leakage in the macular and midperipheral areas. In cases of vision loss in HCQ retinopathy, it is important to consider not only progression of maculopathy, but also development of CME, which can be effectively treated with oral acetazolamide.

  5. Oxygen- and water-induced degradation of an inverted polymer solar cell: the barrier effect

    DEFF Research Database (Denmark)

    Vesterager Madsen, Morten; Norrman, Kion; Krebs, Frederik C

    2011-01-01

    The work focuses on the degradation of performance induced by both water and oxygen in an inverted geometry organic photovoltaic device with emphasis on the accumulated barrier effect of the layers comprising the layer stack. By studying the exchange of oxygen in the zinc oxide (ZnO) layer...... in the humid atmosphere, correlating well with a long observed lifetime in the same atmosphere.© 2011 Society of Photo-Optical Instrumentation Engineers....

  6. TAMOXIFEN RETINOPATHY DURING TREATMENT OF AN INOPERABLE DESMOID TUMOR.

    Science.gov (United States)

    Furst, Meredith; Somogyi, Marie B; Wong, Robert W; Araujo, Dejka; Harper, Clio A

    2017-12-08

    To evaluate the clinical significance and rarity of tamoxifen retinopathy after a long-term tamoxifen treatment for an inoperable desmoid tumor. Case report. Tamoxifen retinopathy is a condition rarely observed in clinical practice. Although tamoxifen is typically a treatment for breast cancer patients, we present a 68-year-old woman taking tamoxifen for an inoperable desmoid tumor, an equally rare condition. She presented with bilaterally deteriorating vision over the course of a year. Fundoscopic examination revealed parafoveal deposits bilaterally. Spectral domain optical coherence tomography exhibited hyperreflective deposits in all layers of the retina. She had a cumulative treatment dose of 292 g of tamoxifen, and the medication was subsequently stopped. Her vision remained stable 3 months after the cessation of tamoxifen. The development of tamoxifen retinopathy in the treatment of a desmoid tumor makes this case a rare entity, and this is the first reported case of these two concomitant conditions to our knowledge. With the use of long-term tamoxifen as a primary treatment, we recommend screening at regular intervals by an ophthalmologist as an integral part of treatment.

  7. Analysis of central corneal thickness in different degrees of diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Shan Hua

    2014-06-01

    Full Text Available AIM: To study central corneal thickness(CCTand correlation in different degrees of diabetic retinopathy(DR.METHODS: A total of 65 cases(130 eyeswith different degrees of DR and 35 normal cases(70 eyesas the age-and gender-matched control group were examined by corneal endothelial microscope, to measure CCT and statistics RESULTS: Compared to control group, there were no significant difference of CCT both mild and medium nonproliferative diabetic retinopathy(NPDRgroups(P>0.05. While the CCT of severe NPDR group and proliferative diabetic retinopathy(PDRgroup were thicker than control group, and the differences were statistically significant(PPPr=0.173, PCONCLUSION: The CCT increases with severity of DR. Taking care of protecting corneal endothelium is very important in the time of therapeutic measure, especially intraocular operation, to decrease complication.

  8. STAGE 5 RETINOPATHY OF PREMATURITY IN ONE EYE – CASE REPORT

    Directory of Open Access Journals (Sweden)

    Gordana Stanković-Babić

    2012-03-01

    Full Text Available Retinopathy of prematurity (ROP is a leading cause of blindness in children and one of the most important reasons of blindness in the perinatal period. The aim of the paper was to present a nine-month-old baby boy with esotropia, microphtalmos and completely detached retina in one eye, as the end stage of the disease, who had not been checked for ROP. The boy was born in the 32nd gestational week, with 1670 g birth weight. Indirect ophthalmoscope examination and ultrasonography of the left eye showed stage 5 retinopathy of prematurity. On the right eye, the finding was valid. Retinopathy of prematurity today needs recognition, understanding and awareness among ophthalmologists, pediatricians, neonatologists. Early diagnosis of damage is important in the treatment of ROP.

  9. Serum TNF-Alpha Level Predicts Nonproliferative Diabetic Retinopathy in Children

    Directory of Open Access Journals (Sweden)

    Katarzyna Zorena

    2007-01-01

    Full Text Available The aim of this study was identification of the immunologic markers of the damage to the eye apparatus at early stages of diabetes mellitus (DM type 1 children. One hundred and eleven children with DM type 1 were divided into two groups: those with nonproliferative diabetic retinopathy (NPDR and without retinopathy. All the children had their daily urine albumin excretion, HbA1c, C-peptide measured, 24-hour blood pressure monitoring, and ophthalmologic examination. Levels of TNF-α, IL-6, and IL-12 in serum were measured by ELISA tests (Quantikine High Sensitivity Human by R&D Systems, Minneapolis, Minn, USA. The NPDR children demonstrated a significantly longer duration of the disease in addition to higher HbA1c, albumin excretion rate, C-reactive protein, systolic blood pressure, as well as TNF-α and IL-6 levels than those without retinopathy. The logistic regression revealed that the risk of NPDR was strongly dependent on TNF-α [(OR 4.01; 95%CI 2.01–7.96]. TNF-α appears to be the most significant predictor among the analyzed parameters of damage to the eye apparatus. The early introduction of the TNF-α antagonists to the treatment of young patients with DM type 1 who show high serum activity of the TNF-α may prevent them from development of diabetic retinopathy.

  10. Ultra-wide-field angiography improves the detection and classification of diabetic retinopathy.

    Science.gov (United States)

    Wessel, Matthew M; Aaker, Grant D; Parlitsis, George; Cho, Minhee; D'Amico, Donald J; Kiss, Szilárd

    2012-04-01

    To evaluate patients with diabetic retinopathy using ultra-wide-field fluorescein angiography and to compare the visualized retinal pathology with that seen on an overly of conventional 7 standard field (7SF) imaging. Two hundred and eighteen eyes of 118 diabetic patients who underwent diagnostic fluorescein angiography using the Optos Optomap Panoramic 200A imaging system were included. The visualized area of the retina, retinal nonperfusion, retinal neovascularization, and panretinal photocoagulation were quantified by two independent masked graders. The respective areas identified on the ultra-wide-field fluorescein angiography image were compared with an overly of a modified 7SF image as outlined in the Early Treatment Diabetic Retinopathy Study. Ultra-wide-field fluorescein angiograms imaging, on average, demonstrated 3.2 times more total retinal surface area than 7SF. When compared with 7SF, ultra-wide-field fluorescein angiography showed 3.9 times more nonperfusion (P diabetic retinopathy. Improved retinal visualization may alter the classification of diabetic retinopathy and may therefore influence follow-up and treatment of these patients.

  11. The role of O-GlcNAc signaling in the pathogenesis of diabetic retinopathy.

    Science.gov (United States)

    Semba, Richard D; Huang, Hu; Lutty, Gerard A; Van Eyk, Jennifer E; Hart, Gerald W

    2014-04-01

    Diabetic retinopathy is a leading cause of blindness worldwide. Despite laser and surgical treatments, antiangiogenic and other therapies, and strict metabolic control, many patients progress to visual impairment and blindness. New insights are needed into the pathophysiology of diabetic retinopathy in order to develop new methods to improve the detection and treatment of disease and the prevention of blindness. Hyperglycemia and diabetes result in increased flux through the hexosamine biosynthetic pathway, which, in turn, results in increased PTM of Ser/Thr residues of proteins by O-linked β-N-acetylglucosamine (O-GlcNAc). O-GlcNAcylation is involved in regulation of many nuclear and cytoplasmic proteins in a manner similar to protein phosphorylation. Altered O-GlcNAc signaling has been implicated in the pathogenesis of diabetes and may play an important role in the pathogenesis of diabetic retinopathy. The goal of this review is to summarize the biology of the hexosamine biosynthesis pathway and O-GlcNAc signaling, to present the current evidence for the role of O-GlcNAc signaling in diabetes and diabetic retinopathy, and to discuss future directions for research on O-GlcNAc in the pathogenesis of diabetic retinopathy. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. VISUAL OUTCOME FOLLOWING PANRETINAL PHOTOCOAGULATION IN PROLIFERATIVE DIABETIC RETINOPATHY

    Directory of Open Access Journals (Sweden)

    Nellaye Mani Sindhu

    2018-01-01

    Full Text Available BACKGROUND Diabetes mellitus can be called as a noninfectious pandemic and the incidence of diabetic retinopathy is also uncontrollable. This vision-threatening complication can be treated by early diagnosis and effective treatment like panretinal photocoagulation. The aim of the study is to evaluate the effect of panretinal photocoagulation on visual acuity, colour vision, contrast sensitivity and severity of visual field changes. MATERIALS AND METHODS Prospective study of visual outcome following panretinal photocoagulation in patients with proliferative diabetic retinopathy conducted in Retina Clinic, RIO, Trivandrum, during the time period one year from April 2008. Inclusion Criteria- Eyes with proliferative diabetic retinopathy, visual acuity better than or equal to 6/60, a follow up of at least 6 months after panretinal photocoagulation. Exclusion Criteria- Eyes with cataractous changes in the lens, eyes, which would be undergoing or have undergone focal photocoagulation eyes, which undergone barrage or sectoral retinal photocoagulation, patients with colour blindness, eyes with vitreous haemorrhage and macular preretinal haemorrhage, glaucomatous patients with peripheral field loss. RESULTS The mean age of the patients was 52 years. Male patients (30 outnumbered the female patients (23. Mean duration of diabetes was 14.42 years. Though, there is a statistically significant reduction in visual acuity in the first followup, which was improved and stabilised by 6 months. There is a statistically significant reduction in the contrast sensitivity, which was stabilised after 3 months. Only, 9.5% patients had peripheral constrictions of visual field and no significant change in the colour vision. CONCLUSION We recommend panretinal photocoagulation for all patients with proliferative diabetic retinopathy.

  13. Automated classifiers for early detection and diagnosis of retinopathy in diabetic eyes.

    Science.gov (United States)

    Somfai, Gábor Márk; Tátrai, Erika; Laurik, Lenke; Varga, Boglárka; Ölvedy, Veronika; Jiang, Hong; Wang, Jianhua; Smiddy, William E; Somogyi, Anikó; DeBuc, Delia Cabrera

    2014-04-12

    Artificial neural networks (ANNs) have been used to classify eye diseases, such as diabetic retinopathy (DR) and glaucoma. DR is the leading cause of blindness in working-age adults in the developed world. The implementation of DR diagnostic routines could be feasibly improved by the integration of structural and optical property test measurements of the retinal structure that provide important and complementary information for reaching a diagnosis. In this study, we evaluate the capability of several structural and optical features (thickness, total reflectance and fractal dimension) of various intraretinal layers extracted from optical coherence tomography images to train a Bayesian ANN to discriminate between healthy and diabetic eyes with and with no mild retinopathy. When exploring the probability as to whether the subject's eye was healthy (diagnostic condition, Test 1), we found that the structural and optical property features of the outer plexiform layer (OPL) and the complex formed by the ganglion cell and inner plexiform layers (GCL + IPL) provided the highest probability (positive predictive value (PPV) of 91% and 89%, respectively) for the proportion of patients with positive test results (healthy condition) who were correctly diagnosed (Test 1). The true negative, TP and PPV values remained stable despite the different sizes of training data sets (Test 2). The sensitivity, specificity and PPV were greater or close to 0.70 for the retinal nerve fiber layer's features, photoreceptor outer segments and retinal pigment epithelium when 23 diabetic eyes with mild retinopathy were mixed with 38 diabetic eyes with no retinopathy (Test 3). A Bayesian ANN trained on structural and optical features from optical coherence tomography data can successfully discriminate between healthy and diabetic eyes with and with no retinopathy. The fractal dimension of the OPL and the GCL + IPL complex predicted by the Bayesian radial basis function network provides better

  14. Global Inhibition of Reactive Oxygen Species (ROS) Inhibits Paclitaxel-Induced Painful Peripheral Neuropathy

    OpenAIRE

    Fidanboylu, Mehmet; Griffiths, Lisa A.; Flatters, Sarah J. L.

    2011-01-01

    Paclitaxel (Taxol (R)) is a widely used chemotherapeutic agent that has a major dose limiting side-effect of painful peripheral neuropathy. Currently there is no effective therapy for the prevention or treatment of chemotherapy-induced painful peripheral neuropathies. Evidence for mitochondrial dysfunction during paclitaxel-induced pain was previously indicated with the presence of swollen and vacuolated neuronal mitochondria. As mitochondria are a major source of reactive oxygen species (ROS...

  15. A case of radiation retinopathy treated with panretinal photocoagulation

    International Nuclear Information System (INIS)

    Ohde, Hisao; Ayaki, Masahiko; Fujimura, Hiromi; Yokoyama, Noriko

    1993-01-01

    A 29-year-old male developed radiation retinopathy one year and three months after 60 Gy of radiotherapy was delivered by a linear accelerator for a grade III astrocytoma. Fundus examination at the initial visit showed several dot and blot hemorrhages and cotton-wool patches. One month later, mascular edema developed due to increased capillary permeability in the left eye, while proliferative changes and preretinal hemorrhages were noted in the right eye. Since panretinal photocoagulation was effective in treating both eyes, it may be the treatment of choice for radiation retinopathy with extensive avascular areas. (author)

  16. The use of statistical methodology to determine the accuracy of grading within a diabetic retinopathy screening programme.

    Science.gov (United States)

    Oke, J L; Stratton, I M; Aldington, S J; Stevens, R J; Scanlon, P H

    2016-07-01

    We aimed to use longitudinal data from an established screening programme with good quality assurance and quality control procedures and a stable well-trained workforce to determine the accuracy of grading in diabetic retinopathy screening. We used a continuous time-hidden Markov model with five states to estimate the probability of true progression or regression of retinopathy and the conditional probability of an observed grade given the true grade (misclassification). The true stage of retinopathy was modelled as a function of the duration of diabetes and HbA1c . The modelling dataset consisted of 65 839 grades from 14 187 people. The median number [interquartile range (IQR)] of examinations was 5 (3, 6) and the median (IQR) interval between examinations was 1.04 (0.99, 1.17) years. In total, 14 227 grades (21.6%) were estimated as being misclassified, 10 592 (16.1%) represented over-grading and 3635 (5.5%) represented under-grading. There were 1935 (2.9%) misclassified referrals, 1305 were false-positive results (2.2%) and 630 were false-negative results (11.0%). Misclassification of background diabetic retinopathy as no detectable retinopathy was common (3.4% of all grades) but rarely preceded referable maculopathy or retinopathy. Misclassification between lower grades of retinopathy is not uncommon but is unlikely to lead to significant delays in referring people for sight-threatening retinopathy. © 2015 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.

  17. Coordination Skills during Vitrectomy in Treatment of Proliferative Diabetic Retinopathy

    Institute of Scientific and Technical Information of China (English)

    Xuehong Chen; Shanshan Luo; Yanchan Liu

    2014-01-01

    Purpose:.To discuss effective nursing and coordination skills for vitrectomy in the treatment of diabetic retinopathy. Methods: Fifty patients (51 eyes) with diabetic retinopathy required vitrectomy were enrolled in this study..Individual nursing service was delivered by strengthening preoperative preparation, providing psychological nursing, and intraopera-tive observation of the severity of diseases by circulating nurses;meticulous nursing was given postoperatively. Results:All 50 patients underwent surgery successfully..Intra-operatively,.patients had stable physical signs..Five patients had postoperative visual acuity0.3..No complicated infection was seen. Conclusion: For patients diagnosed with proliferative diabetic retinopathy requiring vitrectomy,.full preparations should be made and psychological nursing should be delivered preopera-tively, the severity of diseases and clinical reactions should be closely observed intraoperatively,.and proper processing and nursing measures should be taken postoperatively,.which col-lectively enhance surgical success rate,.decrease surgical com-plications,.and attain favorable treatment efficacy.(Eye Science 2014; 29:55-58).

  18. Opposite effects of WR-2721 and WR-1065 on radiation-induced hypothermia: possible correlation with oxygen uptake

    International Nuclear Information System (INIS)

    Kandasamy, S.B.; Kumar, K.S.; Hunt, W.A.; Weiss, J.F.

    1988-01-01

    Ionizing radiation induces hypothermia in guinea pigs. While systemic injection of the radioprotectant S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) did not block hyperthermia induced by exposure to 10 Gy of gamma radiation, central administration did attenuate it. The dephosphorylated metabolite of WR-2721, N-(2-mercaptoethyl)-1,3-diaminopropane (WR-1065), accentuated radiation-induced hypothermia by both routes of administration. In brain homogenates, oxygen uptake was inhibited by WR-2721 but elevated by WR-1065. These results suggest that the antagonism of radiation-induced hypothermia found only after central administration of WR-2721 is due to its direct actions and not to its dephosphorylated metabolite and that this effect may be correlated with the inhibition by WR-2721 of oxygen uptake

  19. Current knowledge on diabetic retinopathy from humandonor tissues

    Institute of Scientific and Technical Information of China (English)

    Jessica H Eisma; Jennifer E Dulle; Patrice E Fort

    2015-01-01

    According to the American Diabetes Association, diabetes was the seventh leading cause of death, and diabetic retinopathy the leading cause of blindness in working age adults in the United States in 2010. Diabetes is characterized by hyperglycemia associated with either hypoinsulinemia or insulin resistance, and over time, this chronic metabolic condition may lead to various complications including kidney failure, heart attacks,and retinal degeneration. In order to better understandthe molecular basis of this disease and its complications,animal models have been the primary approach usedto investigate the effects of diabetes on various tissuesor cell types of the body, including the retina. However,inherent to these animal models are critical limitationsthat make the insight gained from these modelschallenging to apply to the human pathology. Thesedifficulties in translating the knowledge obtained fromanimal studies have led a growing number of researchgroups to explore the diabetes complications, especiallydiabetic retinopathy, on tissues from human donors.This review summarizes the data collected from diabeticpatients at various stages of diabetic retinopathy andclassifies the data based upon their relevance to themain aspects of diabetic retinopathy: retinal vasculaturedysfunction, inflammation, and neurodegeneration. Thisreview discusses the importance of those studies todiscriminate and establish the relevance of the findingsobtained from animal models but also the limitations ofsuch approaches.

  20. Retinal oxygen saturation in relation to retinal thickness in diabetic macular edema

    DEFF Research Database (Denmark)

    Blindbæk, Søren Leer; Peto, Tunde; Grauslund, Jakob

    to retinal thickness in patients with diabetic macular edema (DME). Methods: We included 18 patients with DME that all had central retinal thickness (CRT) >300 µm and were free of active proliferative diabetic retinopathy. Optical coherence tomography (Topcon 3D OCT-2000 spectral domain OCT) was used...... for paracentral edema, the oxygen saturation in the upper and lower temporal arcade branches were compared to the corresponding upper and lower subfield thickness. Spearman’s rank was used to calculate correlation coefficients between CRT and retinal oximetry. Results: Median age and duration of diabetes was 59....... 92.3%, p=0.52). We found no correlation between CRT and retinal oxygen saturation, even when accounting for paracentral edema (p>0.05). Furthermore, there was no difference in retinal oxygen saturation between the macular hemisphere that was more or less affected by DME (p>0.05). Conclusion: Patients...

  1. Evidence for oxygen vacancy or ferroelectric polarization induced switchable diode and photovoltaic effects in BiFeO3 based thin films

    International Nuclear Information System (INIS)

    Guo Yiping; Guo Bing; Dong Wen; Li Hua; Liu Hezhou

    2013-01-01

    The diode and photovoltaic effects of BiFeO 3 and Bi 0.9 Sr 0.1 FeO 3−δ polycrystalline thin films were investigated by poling the films with increased magnitude and alternating direction. It was found that both electromigration of oxygen vacancies and polarization flipping are able to induce switchable diode and photovoltaic effects. For the Bi 0.9 Sr 0.1 FeO 3−δ thin films with high oxygen vacancy concentration, reversibly switchable diode and photovoltaic effects can be observed due to the electromigration of oxygen vacancies under an electric field much lower than its coercive field. However, for the pure BiFeO 3 thin films with lower oxygen vacancy concentration, the reversibly switchable diode and photovoltaic effect is hard to detect until the occurrence of polarization flipping. The switchable diode and photovoltaic effects can be explained well using the concepts of Schottky-like barrier-to-Ohmic contacts resulting from the combination of oxygen vacancies and polarization. The sign of photocurrent could be independent of the direction of polarization when the modulation of the energy band induced by oxygen vacancies is large enough to offset that induced by polarization. The photovoltaic effect induced by the electromigration of oxygen vacancies is unstable due to the diffusion of oxygen vacancies or the recombination of oxygen vacancies with hopping electrons. Our work provides deep insights into the nature of diode and photovoltaic effects in ferroelectric films, and will facilitate the advanced design of switchable devices combining spintronic, electronic, and optical functionalities. (paper)

  2. β2-Adrenergic Receptor Knockout Mice Exhibit A Diabetic Retinopathy Phenotype

    Science.gov (United States)

    Jiang, Youde; Zhang, Qiuhua; Liu, Li; Tang, Jie; Kern, Timothy S.; Steinle, Jena J.

    2013-01-01

    There is considerable evidence from our lab and others for a functional link between β-adrenergic receptor and insulin receptor signaling pathways in retina. Furthermore, we hypothesize that this link may contribute to lesions similar to diabetic retinopathy in that the loss of adrenergic input observed in diabetic retinopathy may disrupt normal anti-apoptotic insulin signaling, leading to retinal cell death. Our studies included assessment of neural retina function (ERG), vascular degeneration, and Müller glial cells (which express only β1 and β2-adrenergic receptor subtypes). In the current study, we produced β2-adrenergic receptor knockout mice to examine this deletion on retinal neurons and vasculature, and to identify specific pathways through which β2-adrenergic receptor modulates insulin signaling. As predicted from our hypothesis, β2-adrenergic receptor knockout mice display certain features similar to diabetic retinopathy. In addition, loss of β2-adrenergic input resulted in an increase in TNFα, a key inhibitor of insulin receptor signaling. Increased TNFα may be associated with insulin-dependent production of the anti-apoptotic factor, Akt. Since the effects occurred in vivo under normal glucose conditions, we postulate that aspects of the diabetic retinopathy phenotype might be triggered by loss of β2-adrenergic receptor signaling. PMID:23894672

  3. The role of serial measurements of serum insulin-like growth factor 1 levels in the development of retinopathy of prematurity.

    Science.gov (United States)

    Dorum, Bayram Ali; Yılmaz, Cansu Canbolat; Köksal, Nilgün; Özkan, Hilal; Yıldız, Meral; Özmen, Ahmet Tuncer

    2017-03-01

    To determine the role of serum insulin-like growth factor-1 levels in the development of retinopathy of prematurity, which is a major cause of childhood blindness worldwide. We prospectively studied newborn infants born at a postmenstrual age of prematurity screening and follow-up. Retinopathy of prematurity was classified according to the international classification of retinopathy of prematurity. Serum Insulin like growth factor 1 levels were measured serially in blood samples on the 1 st , 3 rd , 7 th , 21 st , and 28 th day. Among the 40 infants, 11 (27.5%) constituted the retinopathy of prematurity group and 29 comprised the non-retinopathy of prematurity group. In the retinopathy of prematurity group, the mean gestational age and birth weight was significantly lower. The demographic features of the study cohort were similar. The duration of mechanical ventilation was significantly greater in the retinopathy of prematurity group compared with the non-retinopathy of prematurity group (p=0.036). In terms of neonatal morbidities such as respiratory distress syndrome, intraventricular hemorrhage, bronchopulmonary dysplasia, patent ductus arteriosus, and necrotizing enterocolitis, no differences were detected between the groups. The mean serum insulin-like growth factor-1 levels in retinopathy of prematurity group were significantly lower than those in the non-retinopathy of prematurity group at each time point (1 st , 3 rd , 7 th , 21 st , and 28 th day of postnatal life) (p=0.001). This study demonstrated the low serum insulin-like growth factor-1 levels was associated with retinopathy of prematurity development.

  4. ULTRAHIGH SPEED SWEPT SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF RETINAL AND CHORIOCAPILLARIS ALTERATIONS IN DIABETIC PATIENTS WITH AND WITHOUT RETINOPATHY.

    Science.gov (United States)

    Choi, WooJhon; Waheed, Nadia K; Moult, Eric M; Adhi, Mehreen; Lee, ByungKun; De Carlo, Talisa; Jayaraman, Vijaysekhar; Baumal, Caroline R; Duker, Jay S; Fujimoto, James G

    2017-01-01

    To investigate the utility of ultrahigh speed, swept source optical coherence tomography angiography in visualizing retinal microvascular and choriocapillaris (CC) changes in diabetic patients. The study was prospective and cross-sectional. A 1,050 nm wavelength, 400 kHz A-scan rate swept source optical coherence tomography prototype was used to perform volumetric optical coherence tomography angiography of the retinal and CC vasculatures in diabetic patients and normal subjects. Sixty-three eyes from 32 normal subjects, 9 eyes from 7 patients with proliferative diabetic retinopathy, 29 eyes from 16 patients with nonproliferative diabetic retinopathy, and 51 eyes from 28 diabetic patients without retinopathy were imaged. Retinal and CC microvascular abnormalities were observed in all stages of diabetic retinopathy. In nonproliferative diabetic retinopathy and proliferative diabetic retinopathy, optical coherence tomography angiography visualized a variety of vascular abnormalities, including clustered capillaries, dilated capillary segments, tortuous capillaries, regions of capillary dropout, reduced capillary density, abnormal capillary loops, and foveal avascular zone enlargement. In proliferative diabetic retinopathy, retinal neovascularization above the inner limiting membrane was visualized. Regions of CC flow impairment in patients with proliferative diabetic retinopathy and nonproliferative diabetic retinopathy were also observed. In 18 of the 51 of eyes from diabetic patients without retinopathy, retinal mircrovascular abnormalities were observed and CC flow impairment was found in 24 of the 51 diabetic eyes without retinopathy. The ability of optical coherence tomography angiography to visualize retinal and CC microvascular abnormalities suggests it may be a useful tool for understanding pathogenesis, evaluating treatment response, and earlier detection of vascular abnormalities in patients with diabetes.

  5. Automated Diabetic Retinopathy Image Assessment Software: Diagnostic Accuracy and Cost-Effectiveness Compared with Human Graders.

    Science.gov (United States)

    Tufail, Adnan; Rudisill, Caroline; Egan, Catherine; Kapetanakis, Venediktos V; Salas-Vega, Sebastian; Owen, Christopher G; Lee, Aaron; Louw, Vern; Anderson, John; Liew, Gerald; Bolter, Louis; Srinivas, Sowmya; Nittala, Muneeswar; Sadda, SriniVas; Taylor, Paul; Rudnicka, Alicja R

    2017-03-01

    With the increasing prevalence of diabetes, annual screening for diabetic retinopathy (DR) by expert human grading of retinal images is challenging. Automated DR image assessment systems (ARIAS) may provide clinically effective and cost-effective detection of retinopathy. We aimed to determine whether ARIAS can be safely introduced into DR screening pathways to replace human graders. Observational measurement comparison study of human graders following a national screening program for DR versus ARIAS. Retinal images from 20 258 consecutive patients attending routine annual diabetic eye screening between June 1, 2012, and November 4, 2013. Retinal images were manually graded following a standard national protocol for DR screening and were processed by 3 ARIAS: iGradingM, Retmarker, and EyeArt. Discrepancies between manual grades and ARIAS results were sent to a reading center for arbitration. Screening performance (sensitivity, false-positive rate) and diagnostic accuracy (95% confidence intervals of screening-performance measures) were determined. Economic analysis estimated the cost per appropriate screening outcome. Sensitivity point estimates (95% confidence intervals) of the ARIAS were as follows: EyeArt 94.7% (94.2%-95.2%) for any retinopathy, 93.8% (92.9%-94.6%) for referable retinopathy (human graded as either ungradable, maculopathy, preproliferative, or proliferative), 99.6% (97.0%-99.9%) for proliferative retinopathy; Retmarker 73.0% (72.0 %-74.0%) for any retinopathy, 85.0% (83.6%-86.2%) for referable retinopathy, 97.9% (94.9%-99.1%) for proliferative retinopathy. iGradingM classified all images as either having disease or being ungradable. EyeArt and Retmarker saved costs compared with manual grading both as a replacement for initial human grading and as a filter prior to primary human grading, although the latter approach was less cost-effective. Retmarker and EyeArt systems achieved acceptable sensitivity for referable retinopathy when compared

  6. Comparison of Manual Refraction Versus Autorefraction in 60 Diabetic Retinopathy Patients.

    Science.gov (United States)

    Shirzadi, Keyvan; Shahraki, Kourosh; Yahaghi, Emad; Makateb, Ali; Khosravifard, Keivan

    2016-07-27

    The purpose of the study was to evaluate the comparison of manual refraction versus autorefraction in diabetic retinopathy patients. The study was conducted at the Be'sat Army Hospital from 2013-2015. In the present study differences between two common refractometry methods (manual refractometry and Auto refractometry) in diagnosis and follow up of retinopathy in patients affected with diabetes is investigated. Our results showed that there is a significant difference in visual acuity score of patients between manual and auto refractometry. Despite this fact, spherical equivalent scores of two methods of refractometry did not show a significant statistical difference in the patients. Although use of manual refraction is comparable with autorefraction in evaluating spherical equivalent scores in diabetic patients affected with retinopathy, but in the case of visual acuity results from these two methods are not comparable.

  7. Modification of radiation-induced DNA lesions by oxygen

    International Nuclear Information System (INIS)

    Meyn, R.E.; Jenkins, W.T.

    1984-01-01

    The efficiency of DNA strand break production by radiation under aerated and hypoxic conditions was determined in CHO cells using the technique of alkaline elution. The resulting oxygen enhancement ratio was surprisingly high, 7.8. When the pH of the elution was increased from 12.1, the normally used pH, to 12.8, a substantial increase in the strand breaks produced in the hypoxic cells was observed, resulting in an OER of 4.8. This difference in susceptibility of DNA strand break detection as a function of pH suggested a difference in the type of lesions produced in DNA when irradiated under aerated and hypoxic conditions. Further experiments to examine the DNA-protein crosslinks produced by radiation suggested that the apparent lower level of strand breaks in hypoxic cells may be due to a higher level of DNA-protein crosslinks produced under hypoxic conditions. Thus, oxygen may not only act by modifying the quantity of radiation-induced DNA lesions but may also cause qualitative changes. If the different types of DNA lesions have different contributions to lethality, the OER for cell survival may represent a complex composite of these changes at the molecular level

  8. Hyperbaric oxygen therapy for the treatment of radiation-induced xerostomia: a systematic review.

    Science.gov (United States)

    Fox, Nyssa F; Xiao, Christopher; Sood, Amit J; Lovelace, Tiffany L; Nguyen, Shaun A; Sharma, Anand; Day, Terry A

    2015-07-01

    Radiation-induced xerostomia is one of the most common morbidities of radiation therapy in patients with head and neck cancer. However, in spite of its high rate of occurrence, there are few effective therapies available for its management. The aim of this study was to assess the efficacy of hyperbaric oxygen on the treatment of radiation-induced xerostomia and xerostomia-related quality of life. PubMed, Google Scholar, and the Cochrane Library were searched for retrospective or prospective trials assessing subjective xerostomia, objective xerostomia, or xerostomia-related quality of life. To be included, patients had to have received radiation therapy for head and neck cancer, but not hyperbaric oxygen therapy (HBOT). The systematic review initially identified 293 potential articles. Seven studies, comprising 246 patients, qualified for inclusion. Of the included studies, 6 of 7 were prospective in nature, and 1 was a retrospective study; and 2 of the 7 were controlled studies. HBOT may have utility for treating radiation-induced xerostomia refractory to other therapies. Additionally, HBOT may induce long-term improvement in subjective assessments of xerostomia, whereas other therapies currently available only provide short-term relief. The strength of these conclusions is limited by the lack of randomized controlled clinical trials. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Sex differences in risk factors for retinopathy in non-diabetic men and women: The Tromso Eye Study

    DEFF Research Database (Denmark)

    Bertelsen, G.; Peto, T.; Lindekleiv, H.

    2014-01-01

    Purpose: To determine the prevalence and risk factors for retinopathy in a nondiabetic population. Methods: The study population included 5869 participants without diabetes aged 38-87years from the TromsO Eye Study, a substudy of the population-based TromsO Study in Norway. Retinal images from both...... eyes were graded for retinopathy. We collected data on risk factors from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews. The cross-sectional relationship between potential risk factors and retinopathy was assessed using logistic regression analysis...... excretion (urinary albumin/creatinine ratio >0.43mg/mmol). Conclusion: This study confirms results from previous studies on the strong association between blood pressure and retinopathy. A novel finding is the sex differences in risk factors for retinopathy, suggesting a sex difference in the pathogenesis...

  10. Comparing carotid intima-media thickness in type 2 diabetes between patients with and without retinopathy

    Directory of Open Access Journals (Sweden)

    Naroi Nejad M

    2012-06-01

    Conclusion: Diabetic retinopathy seems to be associated with increased intima-media thickness of carotid arteries in T2DM. It may be a common denominator of pathogene-sis of microvascular complications and atherosclerosis in T2DM. Evaluations of carotid arteries are to be done by non-invasive methods such as color Doppler sonography for screening and preventing prospective cereberovascular accidents in patients with diabetic retinopathy, especially proliferative retinopathy, in routine ophthalmological examination of patients with T2DM.

  11. Hyperbaric Oxygen Therapy for Radiation-Induced Cystitis and Proctitis

    International Nuclear Information System (INIS)

    Oliai, Caspian; Fisher, Brandon; Jani, Ashish; Wong, Michael; Poli, Jaganmohan; Brady, Luther W.; Komarnicky, Lydia T.

    2012-01-01

    Purpose: To provide a retrospective analysis of the efficacy of hyperbaric oxygen therapy (HBOT) for treating hemorrhagic cystitis (HC) and proctitis secondary to pelvic- and prostate-only radiotherapy. Methods and Materials: Nineteen patients were treated with HBOT for radiation-induced HC and proctitis. The median age at treatment was 66 years (range, 15–84 years). The range of external-beam radiation delivered was 50.0–75.6 Gy. Bleeding must have been refractory to other therapies. Patients received 100% oxygen at 2.0 atmospheres absolute pressure for 90–120 min per treatment in a monoplace chamber. Symptoms were retrospectively scored according to the Late Effects of Normal Tissues—Subjective, Objective, Management, Analytic (LENT-SOMA) scale to evaluate short-term efficacy. Recurrence of hematuria/hematochezia was used to assess long-term efficacy. Results: Four of the 19 patients were lost to follow-up. Fifteen patients were evaluated and received a mean of 29.8 dives: 11 developed HC and 4 proctitis. All patients experienced a reduction in their LENT-SOMA score. After completion of HBOT, the mean LENT-SOMA score was reduced from 0.78 to 0.20 in patients with HC and from 0.66 to 0.26 in patients with proctitis. Median follow-up was 39 months (range, 7–70 months). No cases of hematuria were refractory to HBOT. Complete resolution of hematuria was seen in 81% (n = 9) and partial response in 18% (n = 2). Recurrence of hematuria occurred in 36% (n = 4) after a median of 10 months. Complete resolution of hematochezia was seen in 50% (n = 2), partial response in 25% (n = 1), and refractory bleeding in 25% (n = 1). Conclusions: Hyperbaric oxygen therapy is appropriate for radiation-induced HC once less time-consuming therapies have failed to resolve the bleeding. In these conditions, HBOT is efficacious in the short and long term, with minimal side effects.

  12. Bilateral Ocular Decompression Retinopathy after Ahmed Valve Implantation for Uveitic Glaucoma

    Directory of Open Access Journals (Sweden)

    Javier Flores-Preciado

    2016-11-01

    Full Text Available Case Report: We report the case of a 29-year-old man who underwent Ahmed valve implantation in both eyes as treatment for uveitic glaucoma, subsequently presenting with bilateral ocular decompression retinopathy in the postoperative period. Discussion: Ocular decompression retinopathy is a rare complication of filtering surgery in patients with glaucoma; however, the course is benign in most cases, with spontaneous resolution of bleedings and improvement of visual acuity.

  13. Comparison of Manual Refraction Versus Autorefraction in 60 Diabetic Retinopathy Patients

    OpenAIRE

    Shirzadi, Keyvan; Shahraki, Kourosh; Yahaghi, Emad; Makateb, Ali; Khosravifard, Keivan

    2016-01-01

    Aim: The purpose of the study was to evaluate the comparison of manual refraction versus autorefraction in diabetic retinopathy patients. Material and Methods: The study was conducted at the Be?sat Army Hospital from 2013-2015. In the present study differences between two common refractometry methods (manual refractometry and Auto refractometry) in diagnosis and follow up of retinopathy in patients affected with diabetes is investigated. Results: Our results showed that there is a significant...

  14. Predictive algorithms for early detection of retinopathy of prematurity.

    Science.gov (United States)

    Piermarocchi, Stefano; Bini, Silvia; Martini, Ferdinando; Berton, Marianna; Lavini, Anna; Gusson, Elena; Marchini, Giorgio; Padovani, Ezio Maria; Macor, Sara; Pignatto, Silvia; Lanzetta, Paolo; Cattarossi, Luigi; Baraldi, Eugenio; Lago, Paola

    2017-03-01

    To evaluate sensitivity, specificity and the safest cut-offs of three predictive algorithms (WINROP, ROPScore and CHOP ROP) for retinopathy of prematurity (ROP). A retrospective study was conducted in three centres from 2012 to 2014; 445 preterms with gestational age (GA) ≤ 30 weeks and/or birthweight (BW) ≤ 1500 g, and additional unstable cases, were included. No-ROP, mild and type 1 ROP were categorized. The algorithms were analysed for infants with all parameters (GA, BW, weight gain, oxygen therapy, blood transfusion) needed for calculation (399 babies). Retinopathy of prematurity (ROP) was identified in both eyes in 116 patients (26.1%), and 44 (9.9%) had type 1 ROP. Gestational age and BW were significantly lower in ROP group compared with no-ROP subjects (GA: 26.7 ± 2.2 and 30.2 ± 1.9, respectively, p < 0.0001; BW: 839.8 ± 287.0 and 1288.1 ± 321.5 g, respectively, p = 0.0016). Customized alarms of ROPScore and CHOP ROP correctly identified all infants having any ROP or type 1 ROP. WINROP missed 19 cases of ROP, including three type 1 ROP. ROPScore and CHOP ROP provided the best performances with an area under the receiver operating characteristic curve for the detection of severe ROP of 0.93 (95% CI, 0.90-0.96, and 95% CI, 0.89-0.96, respectively), and WINROP obtained 0.83 (95% CI, 0.77-0.87). Median time from alarm to treatment was 11.1, 5.1 and 9.1 weeks, for WINROP, ROPScore and CHOP ROP, respectively. ROPScore and CHOP ROP showed 100% sensitivity to identify sight-threatening ROP. Predictive algorithms are a reliable tool for early identification of infants requiring referral to an ophthalmologist, for reorganizing resources and reducing stressful procedures to preterm babies. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  15. Detection of neovascularization based on fractal and texture analysis with interaction effects in diabetic retinopathy.

    Science.gov (United States)

    Lee, Jack; Zee, Benny Chung Ying; Li, Qing

    2013-01-01

    Diabetic retinopathy is a major cause of blindness. Proliferative diabetic retinopathy is a result of severe vascular complication and is visible as neovascularization of the retina. Automatic detection of such new vessels would be useful for the severity grading of diabetic retinopathy, and it is an important part of screening process to identify those who may require immediate treatment for their diabetic retinopathy. We proposed a novel new vessels detection method including statistical texture analysis (STA), high order spectrum analysis (HOS), fractal analysis (FA), and most importantly we have shown that by incorporating their associated interactions the accuracy of new vessels detection can be greatly improved. To assess its performance, the sensitivity, specificity and accuracy (AUC) are obtained. They are 96.3%, 99.1% and 98.5% (99.3%), respectively. It is found that the proposed method can improve the accuracy of new vessels detection significantly over previous methods. The algorithm can be automated and is valuable to detect relatively severe cases of diabetic retinopathy among diabetes patients.

  16. Detection of neovascularization based on fractal and texture analysis with interaction effects in diabetic retinopathy.

    Directory of Open Access Journals (Sweden)

    Jack Lee

    Full Text Available Diabetic retinopathy is a major cause of blindness. Proliferative diabetic retinopathy is a result of severe vascular complication and is visible as neovascularization of the retina. Automatic detection of such new vessels would be useful for the severity grading of diabetic retinopathy, and it is an important part of screening process to identify those who may require immediate treatment for their diabetic retinopathy. We proposed a novel new vessels detection method including statistical texture analysis (STA, high order spectrum analysis (HOS, fractal analysis (FA, and most importantly we have shown that by incorporating their associated interactions the accuracy of new vessels detection can be greatly improved. To assess its performance, the sensitivity, specificity and accuracy (AUC are obtained. They are 96.3%, 99.1% and 98.5% (99.3%, respectively. It is found that the proposed method can improve the accuracy of new vessels detection significantly over previous methods. The algorithm can be automated and is valuable to detect relatively severe cases of diabetic retinopathy among diabetes patients.

  17. Comparison of six-minute walking tests conducted with and without supplemental oxygen in patients with chronic obstructive pulmonary disease and exercise-induced oxygen desaturation

    International Nuclear Information System (INIS)

    Ozalevli, S.; Ozden, A.; Gocen, Z.; Cimrin, Arif Hikmet

    2007-01-01

    There are contradictory reports in the literature on the supplemental oxygen administered before or after exercise tests. In light of this, we compared the results of 6-minute walking tests performed in room-air conditions (A6MWT) in patients with supplemental oxygen (O6MWT) in patients with chronic obstructive pulmonary disease (COPD) and exercise-induced oxygen desaturation. Thirty-one patients with COPD were included in the study. The A6MWT and O6MWT were performed in randomized order on each patient. During the tests, severity dyspenia and tiring of the leg were evaluated by the Modified Borg Scale. Heart rate and pulsed oxygen saturation and blood pressure were measured by pulse oximeter. Walking distance was longer with the O6MWT than with the A6MWT (P=0.001). The O6MWT resulted in a smaller increase in dyspnea, leg fatigue and heart rate and a smaller drop in pulsed saturation than the A6MWT (P<0.05). The walking distance with O6MWT correlated with respiratory function and hemodynamic parameters (P<0.05). The O6MWT, which produced less hemodynamic stress and was safer than the A6MWT, might provide more accurate information on exercise limitations for patients with COPD. These results suggest that the O6MWT can be used as a standard walking exercise test for patients with COPd and exercise-induced oxygen desaturation. (author)

  18. Vision-Related Functional Burden of Diabetic Retinopathy Across Severity Levels in the United States.

    Science.gov (United States)

    Willis, Jeffrey R; Doan, Quan V; Gleeson, Michelle; Haskova, Zdenka; Ramulu, Pradeep; Morse, Lawrence; Cantrell, Ronald A

    2017-09-01

    Among adults with diabetes in the United States, severe forms of diabetic retinopathy (DR) are significantly associated with a greater vision-related functional burden. To assess the functional burden of DR across severity levels in the United States. This cross-sectional study was based on 1004 participants 40 years or older with diabetes and valid ocular and sociodemographic outcomes in the National Health and Nutrition Examination Surveys (NHANES) (2005-2006 and 2007-2008). Diabetic retinopathy was based on fundus photograph grading, using the Early Treatment Diabetic Retinopathy Study severity scale. The analysis was performed from October 15, 2016, to June 15, 2017. Functional difficulties secondary to vision were assessed during a household questionnaire in which participants self-reported difficulty with reading, visuospatial tasks (ie, close-up work or finding things on a crowded shelf), mobility (ie, walking down steps, stairs, or curbs), and driving. The main outcome measure was vision-related functional burden, which was defined as present for individuals reporting moderate or greater difficulty in any of the aforementioned tasks. Of the 1004 persons with diabetes analyzed for this study (mean age, 65.7 years [95% CI, 64.0-67.3 years]; 51.1% male [95% CI, 47.1-55.2] and 48.9% female [95% CI, 44.8-52.9]), the prevalence was 72.3% for no retinopathy, 25.4% for mild and moderate nonproliferative diabetic retinopathy (NPDR), and 2.3% for severe NPDR or proliferative diabetic retinopathy (PDR). The prevalence of vision-related functional burden was 20.2% (95% CI, 16.3%-24.1%) for those with no retinopathy, 20.4% (95% CI, 15.3%-27.8%) for those with mild and moderate NPDR, and 48.5% (95% CI, 25.6%-71.5%) for those with severe NPDR or PDR (P = .02). In multivariable analysis, the odds of vision-related functional burden were significantly greater among those with severe NPDR or PDR relative to those with no retinopathy (adjusted odds ratio [aOR], 3.59; 95

  19. Study of serum soluble vascular cell adhesion molecule-1 levels in type 2 diabetic patients with diabetic retinopathy

    International Nuclear Information System (INIS)

    Li Fangdu; Chu Qiaomei

    2002-01-01

    To study the change and the correlation of serum soluble vascular cell adhesion molecule-1 (sV-CAM-1) levels with diabetic retinopathy in type 2 diabetic patients, serum sVCAM-1 levels were measured in duplicate by ELISA in 85 type 2 diabetic patients; fundus examination was performed by an ophthalmologist using ophthalmoscope or fundus fluorescein angiography, and the findings were graded as: no signs of diabetic retinopathy (NDR), background diabetic retinopathy (BDR) and proliferative diabetic retinopathy (PDR). Serum sVCAM-1 levels were significantly higher in the PDR and BDR groups than those in the control and NDR groups respectively (P<0.01). NDR group showed significantly increased serum sVCAM-levels compared with control group (P<0.01). In contrast, serum sVCAM-1 levels were not related to the presence of blood glucose, serum insulin levels or known diabetic duration. Authors' results suggest that serum sVCAM-1 might be implicated in the development of the diabetic retinopathy, and could assess the severity of diabetic retinopathy. The measurement of serum sVCAM-1 levels in 2 type diabetic patients may be clinically useful for early diagnosis or treatment of diabetic retinopathy

  20. Diabetic retinopathy in pregnancy: a population-based study of women with pregestational diabetes.

    LENUS (Irish Health Repository)

    Egan, Aoife M

    2015-04-01

    The aim of this observational study was to evaluate screening and progression of diabetic retinopathy during pregnancy in women with pregestational diabetes attending five antenatal centres along the Irish Atlantic seaboard. An adequate frequency of screening was defined as at least two retinal evaluations in separate trimesters. Progression was defined as at least one stage of deterioration of diabetic retinopathy and\\/or development of diabetic macular edema on at least one eye. Women with pregestational diabetes who delivered after 22 gestational weeks (n = 307) were included. In total, 185 (60.3%) had an adequate number of retinal examinations. Attendance at prepregnancy care was associated with receiving adequate screening (odds ratio 6.23; CI 3.39-11.46 (P < 0.001)). Among those who received adequate evaluations (n = 185), 48 (25.9%) had retinopathy progression. Increasing booking systolic blood pressure (OR 1.03, CI 1.01-1.06, P = 0.02) and greater drop in HbA1c between first and third trimesters of pregnancy (OR 2.05, CI 1.09-3.87, P = 0.03) significantly increased the odds of progression. A significant proportion of women continue to demonstrate retinopathy progression during pregnancy. This study highlights the role of prepregnancy care and the importance of close monitoring during pregnancy and identifies those patients at the highest risk for retinopathy progression.

  1. Automated detection of diabetic retinopathy lesions on ultrawidefield pseudocolour images.

    Science.gov (United States)

    Wang, Kang; Jayadev, Chaitra; Nittala, Muneeswar G; Velaga, Swetha B; Ramachandra, Chaithanya A; Bhaskaranand, Malavika; Bhat, Sandeep; Solanki, Kaushal; Sadda, SriniVas R

    2018-03-01

    We examined the sensitivity and specificity of an automated algorithm for detecting referral-warranted diabetic retinopathy (DR) on Optos ultrawidefield (UWF) pseudocolour images. Patients with diabetes were recruited for UWF imaging. A total of 383 subjects (754 eyes) were enrolled. Nonproliferative DR graded to be moderate or higher on the 5-level International Clinical Diabetic Retinopathy (ICDR) severity scale was considered as grounds for referral. The software automatically detected DR lesions using the previously trained classifiers and classified each image in the test set as referral-warranted or not warranted. Sensitivity, specificity and the area under the receiver operating curve (AUROC) of the algorithm were computed. The automated algorithm achieved a 91.7%/90.3% sensitivity (95% CI 90.1-93.9/80.4-89.4) with a 50.0%/53.6% specificity (95% CI 31.7-72.8/36.5-71.4) for detecting referral-warranted retinopathy at the patient/eye levels, respectively; the AUROC was 0.873/0.851 (95% CI 0.819-0.922/0.804-0.894). Diabetic retinopathy (DR) lesions were detected from Optos pseudocolour UWF images using an automated algorithm. Images were classified as referral-warranted DR with a high degree of sensitivity and moderate specificity. Automated analysis of UWF images could be of value in DR screening programmes and could allow for more complete and accurate disease staging. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Postnatal Growth and Retinopathy of Prematurity Study: Rationale, Design, and Subject Characteristics.

    Science.gov (United States)

    Binenbaum, Gil; Tomlinson, Lauren A

    2017-02-01

    Postnatal-growth-based predictive models demonstrate strong potential for improving the low specificity of retinopathy of prematurity (ROP) screening. Prior studies are limited by inadequate sample size. We sought to study a sufficiently large cohort of at-risk infants to enable development of a model with highly precise estimates of sensitivity for severe ROP. The Postnatal Growth and ROP (G-ROP) Study was a multicenter retrospective cohort study of infants at 30 North American hospitals during 2006-2012. A total of 65 G-ROP-certified abstractors submitted data to a secure, web-based database. Data included ROP examination findings, treatments, complications, daily weight measurements, daily oxygen supplementation, maternal/infant demographics, medical comorbidities, surgical events, and weekly nutrition. Data quality was monitored with system validation rules, data audits, and discrepancy algorithms. Of 11,261 screened infants, 8334 were enrolled, and 2927 had insufficient data due to transfer, discharge, or death. Of the enrolled infants, 90% (7483) had a known ROP outcome and were included in the study. Median birth weight was 1070 g (range 310-3000g) and mean gestational age 28 weeks (range 22-35 weeks). Severe ROP (Early Treatment of Retinopathy type 1 or 2) developed in 931 infants (12.5%). Successful incorporation of a predictive model into ROP screening requires confidence that it will capture cases of severe ROP. This dataset provides power to estimate sensitivity with half-confidence interval width of less than 0.5%, determined by the high number of severe ROP cases. The G-ROP Study represents a large, diverse cohort of at-risk infants undergoing ROP screening. It will facilitate evaluation of growth-based algorithms to improve efficiency of ROP screening.

  3. Nitric oxide and oxidative stress is associated with severity of diabetic retinopathy and retinal structural alterations.

    Science.gov (United States)

    Sharma, Shashi; Saxena, Sandeep; Srivastav, Khushboo; Shukla, Rajendra K; Mishra, Nibha; Meyer, Carsten H; Kruzliak, Peter; Khanna, Vinay K

    2015-07-01

    The aim of the study was to determine plasma nitric oxide (NO) and lipid peroxide (LPO) levels in diabetic retinopathy and its association with severity of disease. Prospective observational study. A total of 60 consecutive cases and 20 healthy controls were included. Severity of retinopathy was graded according to early treatment diabetic retinopathy study (ETDRS) classification. Photoreceptor inner segment ellipsoid band (ISel) disruption and retinal pigment epithelium (RPE) alteration were graded using spectral domain optical coherence tomography. Data were statistically analyzed. Plasma thiobarbituric acid reactive substances, NO assay and reduced glutathione (GSH) were measured using standard protocol. Increased severity of diabetic retinopathy was significantly associated with increase in plasma levels of LPO (P diabetic retinopathy. For the first time, it has been demonstrated that increased plasma LPO, NO and decreased GSH levels are associated with in vivo structural changes in inner segment ellipsoid and RPE. © 2015 Royal Australian and New Zealand College of Ophthalmologists.

  4. Association between high risk foot, retinopathy and HBA1c in Saudi diabetic population

    International Nuclear Information System (INIS)

    Mehmood, K.; Aziz, A.

    2010-01-01

    Background: One of the important complications of diabetes is diabetic-foot-ulcer, also reported in Saudi Arabia, like other countries. Similarly, the complications, like retinopathy and nephropathy are also occurring in diabetic patients of this region. Apart from the care and monitoring of these patients, it is important to find out association between these complications and their relation with common factors, like HbA1c levels. Such relation is not yet reported in literature. Objective: Therefore, this study was planned to find out association between neuropathy (leading to high risk foot) and retinopathy by the estimation of HbA1c levels in Saudi population. Methods: After exclusion of the cases of gestational diabetes and children with type-1 diabetes, 333 Patients having age 21 to 97 years were examined in the Diabetology Clinic of Diabetes Centre, Aseer Central Hospital, Abha. All patients were screened for neuropathy (High risk of the foot) and retinopathy (by Fundus Photography). HbA1c levels were determined, using standardised procedure. The obtained data was analysed statistically by SPSS-12 for Windows. Results: HbA1c levels of less than or equal to have been found to be associated with neuropathy, high risk foot, and as well as non- proliferative and proliferative retinopathy. Pearson chi square test has demonstrated association between progressive retinopathy and development of high risk foot. Conclusion: The observed data indicate poor glycemic or diabetes control on the basis of higher HbA1c levels and strong association between high risk foot and the development of progressive retinopathy. (author)

  5. Role of early screening for diabetic retinopathy in patients with diabetes mellitus: An overview

    Directory of