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  1. Relationship between retinal blood flow and arterial oxygen.

    Science.gov (United States)

    Cheng, Richard W; Yusof, Firdaus; Tsui, Edmund; Jong, Monica; Duffin, James; Flanagan, John G; Fisher, Joseph A; Hudson, Chris

    2016-02-01

    Vascular reactivity, the response of the vessels to a vasoactive stimulus such as hypoxia and hyperoxia, can be used to assess the vascular range of adjustment in which the vessels are able to compensate for changes in PO2. Previous studies in the retina have not accurately quantified retinal vascular responses and precisely targeted multiple PaO2 stimuli at the same time as controlling the level of carbon dioxide, thus precluding them from modelling the relationship between retinal blood flow and oxygen. The present study modelled the relationship between retinal blood flow and PaO2, showing them to be a combined linear and hyperbolic function. This model demonstrates that the resting tonus of the vessels is at the mid-point and that they have great vascular range of adjustment, compensating for decreases in oxygen above a PETCO2 of 32-37 mmHg but being limited below this threshold. Retinal blood flow (RBF) increases in response to a reduction in oxygen (hypoxia) but decreases in response to increased oxygen (hyperoxia). However, the relationship between blood flow and the arterial partial pressure of oxygen has not been quantified and modelled in the retina, particularly in the vascular reserve and resting tonus of the vessels. The present study aimed to determine the limitations of the retinal vasculature by modelling the relationship between RBF and oxygen. Retinal vascular responses were measured in 13 subjects for eight different blood gas conditions, with the end-tidal partial pressure of oxygen (PETCO2) ranging from 40-500 mmHg. Retinal vascular response measurements were repeated twice; using the Canon laser blood flowmeter (Canon Inc., Tokyo, Japan) during the first visit and using Doppler spectral domain optical coherence tomography during the second visit. We determined that the relationship between RBF and PaO2 can be modelled as a combination of hyperbolic and linear functions. We concluded that RBF compensated for decreases in arterial oxygen content

  2. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... for CRVE, and 0.67 +/- 0.05 microm for AVR. No significant influence on artery or vein diameters was found for gender, smoking, body mass index (BMI), total cholesterol, fasting blood glucose, or 2-hour oral glucose tolerance test values. CONCLUSIONS: In healthy young adults with normal blood pressure...

  3. Altered Antioxidant-Oxidant Status in the Aqueous Humor and Peripheral Blood of Patients with Retinitis Pigmentosa

    Science.gov (United States)

    Martínez-Fernández de la Cámara, Cristina; Salom, David; Sequedo, Ma Dolores; Hervás, David; Marín-Lambíes, Cristina; Aller, Elena; Jaijo, Teresa; Díaz-LLopis, Manuel; Millán, José María; Rodrigo, Regina

    2013-01-01

    Retinitis Pigmentosa is a common form of hereditary retinal degeneration constituting the largest Mendelian genetic cause of blindness in the developed world. It has been widely suggested that oxidative stress possibly contributes to its pathogenesis. We measured the levels of total antioxidant capacity, free nitrotyrosine, thiobarbituric acid reactive substances (TBARS) formation, extracellular superoxide dismutase (SOD3) activity, protein, metabolites of the nitric oxide/cyclic GMP pathway, heme oxygenase-I and inducible nitric oxide synthase expression in aqueous humor or/and peripheral blood from fifty-six patients with retinitis pigmentosa and sixty subjects without systemic or ocular oxidative stress-related disease. Multivariate analysis of covariance revealed that retinitis pigmentosa alters ocular antioxidant defence machinery and the redox status in blood. Patients with retinitis pigmentosa present low total antioxidant capacity including reduced SOD3 activity and protein concentration in aqueous humor. Patients also show reduced SOD3 activity, increased TBARS formation and upregulation of the nitric oxide/cyclic GMP pathway in peripheral blood. Together these findings confirmed the hypothesis that patients with retinitis pigmentosa present reduced ocular antioxidant status. Moreover, these patients show changes in some oxidative-nitrosative markers in the peripheral blood. Further studies are needed to clarify the relationship between these peripheral markers and retinitis pigmentosa. PMID:24069283

  4. Quantitative and qualitative retinal microvascular characteristics and blood pressure.

    Science.gov (United States)

    Cheung, Carol Y; Tay, Wan T; Mitchell, Paul; Wang, Jie J; Hsu, Wynne; Lee, Mong L; Lau, Qiangfeng P; Zhu, Ai L; Klein, Ronald; Saw, Seang M; Wong, Tien Y

    2011-07-01

    The present study examined the effects of blood pressure on a spectrum of quantitative and qualitative retinal microvascular signs. Retinal photographs from the Singapore Malay Eye Study, a population-based cross-sectional study of 3280 (78.7% response) persons aged 40-80 years, were analyzed. Quantitative changes in the retinal vasculature (branching angle, vascular tortuosity, fractal dimension, and vascular caliber) were measured using a semi-automated computer-based program. Qualitative signs, including focal arteriolar narrowing (FAN), arteriovenous nicking (AVN), opacification of the arteriolar wall (OAW), and retinopathy (e.g., microaneurysms, retinal hemorrhages), were assessed from photographs by trained technicians. After excluding persons with diabetes and ungradable photographs, 1913 persons provided data for this analysis. In multivariable linear regression models controlling for age, sex, BMI, use of antihypertensive medication, and other factors, retinal arteriolar branching asymmetry ratio, arteriolar tortuosity, venular tortuosity, fractal dimension, arteriolar caliber, venular caliber, FAN, AVN, and retinopathy were independently associated with mean arterial blood pressure. In contrast, arteriolar/venular branching angle, venular branching asymmetry ratio and OAW were not related to blood pressure. Retinal arteriolar caliber (sβ = -0.277) and FAN (sβ = 0.170) had the strongest associations with mean arterial blood pressure, and higher blood pressure levels were associated with increasing number of both quantitative and qualitative retinal vascular signs (P trend qualitative retinal vascular signs, with the number of signs increasing with higher blood pressure levels.

  5. C-reactive protein and chitinase 3-like protein 1 as biomarkers of spatial redistribution of retinal blood vessels on digital retinal photography in patients with diabetic retinopathy.

    Science.gov (United States)

    Cekić, Sonja; Cvetković, Tatjana; Jovanović, Ivan; Jovanović, Predrag; Pesić, Milica; Stanković Babić, Gordana; Milenković, Svetislav; Risimić, Dijana

    2014-08-20

    The aim of the study was to investigate the correlation between the levels of C-reactive protein (CRP) and chitinase 3-like protein 1 (YKL-40) in blood samples with morpohometric parameters of retinal blood vessels in patients with diabetic retinopathy. Blood laboratory examination of 90 patients included the measurement of glycemia, HbA1C, total cholesterol, LDL-C, HDL-C, triglycerides and CRP. Levels of YKL-40 were detected and measured in serum by ELISA (Micro VueYKL-40 EIA Kit, Quidel Corporation, San Diego, USA). YKL-40 correlated positively with diameter and negatively with number of retinal blood vessels. The average number of the blood vessels per retinal zone was significantly higher in the group of patients with mild non-proliferative diabetic retinopathy than in the group with severe form in the optic disc and all five retinal zones. The average outer diameter of the evaluated retinal zones and optic disc vessels was significantly higher in the group with severe compared to the group with mild diabetic retinopathy. Morphological analysis of the retinal vessels on digital fundus photography and correlation with YKL-40 may be valuable for the follow-up of diabetic retinopathy.

  6. Association of ABO blood groups and Rh factor with retinal and choroidal thickness.

    Science.gov (United States)

    Teberik, Kuddusi; Eski, Mehmet Tahir

    2018-06-01

    To evaluate if ABO blood group and Rh factor have an effect on retinal and choroidal thickness. This study was designed prospectively. Retinal nerve fiber layer, retinal, and choroidal thicknesses were measured with spectral-domain optical coherence tomography. Retinal and choroidal thickness measurements (one subfoveal, three temporal, and three nasal) were obtained at 500-μm intervals up to 1500 μm with the caliper system. In this study, 109 male and 151 female, 260 individuals in total were included. There were 125 subjects in group A, 29 in group B, 34 in group AB, and 72 in group O. Rh factor was positive in 194 subjects and negative in 66. There was no significant difference between the groups regarding age (p = 0.667). The groups did not show any statistical difference in retinal nerve fiber layer thickness. There was significant difference found for mean retinal thickness at temporal 1000 μm when four groups were compared (p = 0.037). No statistically significant difference was detected for the remaining retinal and choroidal sectoral regions. The groups did not statistically significantly differ concerning Rh factor (p > 0.05). Although we found a significant difference in retinal thickness in the temporal retina between group B with group A and group O, we suggest that both blood group and Rh factor have no effect on retinal and choroidal thickness.

  7. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length

    International Nuclear Information System (INIS)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu; Jiao, Shuliang; Zhang, Hao F.

    2015-01-01

    Purpose: Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. Methods: The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. Results: In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild-type rats. The authors’ measured flow rates were consistent with results in the literature. Conclusions: By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length

  8. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length.

    Science.gov (United States)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu; Jiao, Shuliang; Zhang, Hao F

    2015-09-01

    Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as -0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31 μl/min among four wild-type rats. The authors' measured flow rates were consistent with results in the literature. By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.

  9. Measuring retinal blood flow in rats using Doppler optical coherence tomography without knowing eyeball axial length

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenzhong; Yi, Ji; Chen, Siyu [Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Jiao, Shuliang [Department of Biomedical Engineering, Florida International University, Miami, Florida 33174 (United States); Zhang, Hao F., E-mail: hfzhang@northwestern.edu [Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208 and Department of Ophthalmology, Northwestern University, Chicago, Illinois 60611 (United States)

    2015-09-15

    Purpose: Doppler optical coherence tomography (OCT) is widely used for measuring retinal blood flow. Existing Doppler OCT methods require the eyeball axial length, in which empirical values are usually used. However, variations in the axial length can create a bias unaccounted for in the retinal blood flow measurement. The authors plan to develop a Doppler OCT method that can measure the total retinal blood flow rate without requiring the eyeball axial length. Methods: The authors measured the retinal blood flow rate using a dual-ring scanning protocol. The small and large scanning rings entered the eye at different incident angles (small ring: 4°; large ring: 6°), focused on different locations on the retina, and detected the projected velocities/phase shifts along the probing beams. The authors calculated the ratio of the projected velocities between the two rings, and then used this ratio to estimate absolute flow velocity. The authors tested this method in both Intralipid phantoms and in vivo rats. Results: In the Intralipid flow phantom experiments, the preset and measured flow rates were consistent with the coefficient of determination as 0.97. Linear fitting between preset and measured flow rates determined the fitting slope as 1.07 and the intercept as −0.28. In in vivo rat experiments, the measured average total retinal blood flow was 7.02 ± 0.31μl/min among four wild-type rats. The authors’ measured flow rates were consistent with results in the literature. Conclusions: By using a dual-ring scanning protocol with carefully controlled incident angle difference between the two scanning rings in Doppler OCT, the authors demonstrated that it is feasible to measure the absolute retinal blood flow without knowing the eyeball axial length.

  10. Automatic segmentation of blood vessels from retinal fundus images ...

    Indian Academy of Sciences (India)

    The retinal blood vessels were segmented through color space conversion and color channel .... Retinal blood vessel segmentation was also attempted through multi-scale operators. A few works in this ... fundus camera at 35 degrees field of view. The image ... vessel segmentation is available from two human observers.

  11. C - reactive protein and chitinase 3-like protein 1 as biomarkers of spatial redistribution of retinal blood vessels on digital retinal photography in patients with diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Sonja Predrag Cekic

    2014-08-01

    Full Text Available The aim of the study was to investegate the correlation between the levels of CRP and YKL-40 in blood samples with morphometric parameters of retinal blood vessels in patients with diabetic retinopathy.Blood laboratory examination of 90 patients included the measurement of glycemia, HbA1C, total cholesterol, LDL-C, HDL-C, triglycerides and CRP. Levels of YKL-40 were detected and measured in serum by ELISA (Micro VueYKL-40 EIA Kit, Quidel Corporation, San Diego, USA.Morphmetric analysis was performed with ImageJ software (http://rsbweb.nih.gov/ij/ for digital retinal photography. We measured the number, diameter of retinal blood vessels in five different parts concentric to the optic disc. Differences between the morphometric parameters and the blood test analysis results were evaluated using the Student’s t – test. One Way ANOVA was used to establish the significance of differences.CRP and YKL-40 levels were moderately higher in the group of patients with severe diabetic retinopathy. Levels of YKL-40 correlated positively with diameter and negatively with number of retinal blood vessels. The average number of the blood vessels per retinal zone was significantly higher in the group of patients with mild non-proliferative diabetic retinopathy than in the group with severe form in the optic disc and all five retinal zones. The average outer diameter of the evaluated retinal zones and optic disc vessels was significantly higher in the group with severe compared to the group with mild diabetic retinopathy.Morphological analysis of the retinal vessels on digital fundus photography and correlation with YKL-40 may be valuable for the follow-up of diabetic retinopathy.

  12. Application of morphological bit planes in retinal blood vessel extraction.

    Science.gov (United States)

    Fraz, M M; Basit, A; Barman, S A

    2013-04-01

    The appearance of the retinal blood vessels is an important diagnostic indicator of various clinical disorders of the eye and the body. Retinal blood vessels have been shown to provide evidence in terms of change in diameter, branching angles, or tortuosity, as a result of ophthalmic disease. This paper reports the development for an automated method for segmentation of blood vessels in retinal images. A unique combination of methods for retinal blood vessel skeleton detection and multidirectional morphological bit plane slicing is presented to extract the blood vessels from the color retinal images. The skeleton of main vessels is extracted by the application of directional differential operators and then evaluation of combination of derivative signs and average derivative values. Mathematical morphology has been materialized as a proficient technique for quantifying the retinal vasculature in ocular fundus images. A multidirectional top-hat operator with rotating structuring elements is used to emphasize the vessels in a particular direction, and information is extracted using bit plane slicing. An iterative region growing method is applied to integrate the main skeleton and the images resulting from bit plane slicing of vessel direction-dependent morphological filters. The approach is tested on two publicly available databases DRIVE and STARE. Average accuracy achieved by the proposed method is 0.9423 for both the databases with significant values of sensitivity and specificity also; the algorithm outperforms the second human observer in terms of precision of segmented vessel tree.

  13. Influencing factors affecting the retinal blood vessel morphology in patients with diabetes mellitus

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    Xiao-Lu Kong

    2017-03-01

    Full Text Available AIM: To analyze the influencing factors affecting retinal blood vessel morphology in patients with diabetes mellitus. METHODS: Totally 312 patients with type 2 diabetes mellitus in our hospital from January 2012 to September 2016 were selected as study subjects. The patients were examined by fundus photography and related laboratory. As grouping factors in the patients'age, sex, disease duration, smoking, drinking, hypertension, hyperlipidemia or diabetic nephropathy, we compared the incidence of retinal vascular changes in different groups. The meaningful factors were introduced into the Logistic regression equation again. Independent risk factors for retinal vascular changes in patients with diabetes mellitus were screened out. RESULTS:In 312 cases of patients with type 2 diabetes mellitus,169 cases were accompanied with retinal vascular abnormalities, and 143 cases were not associated with retinal vascular abnormalities. Univariate analysis showed that age, duration of disease, hypertension, hyperlipidemia or diabetes nephropathy were significantly correlated with retinal vascular morphological changes(PP>0.05. Retinal vascular abnormalities were used as the dependent variable, and the above mentioned factors were grouped as independent variables. By Logistic stepwise regression analysis showed that the course of disease, patients with hypertension or diabetic nephropathy were the independent risk factors of abnormal retinal vascular morphology(PCONCLUSION: The independent risk factors for the occurrence of retinal vascular changes in patients with diabetes mellitus are increased course of disease, hypertension or diabetic nephropathy. Early diagnosis and intervention, to take measures and control blood pressure, reduce kidney damage can reduce the incidence of diabetic retinopathy, and macrovascular disease caused by diabetes, the incidence of adverse cardiovascular and cerebrovascular events.

  14. Blood pressure modifies retinal susceptibility to intraocular pressure elevation.

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    Zheng He

    Full Text Available Primary open angle glaucoma affects more than 67 million people. Elevated intraocular pressure (IOP is a risk factor for glaucoma and may reduce nutrient availability by decreasing ocular perfusion pressure (OPP. An interaction between arterial blood pressure and IOP determines OPP; but the exact contribution that these factors have for retinal function is not fully understood. Here we sought to determine how acute modifications of arterial pressure will affect the susceptibility of neuronal function and blood flow to IOP challenge. Anaesthetized (ketamine:xylazine Long-Evan rats with low (∼60 mmHg, sodium nitroprusside infusion, moderate (∼100 mmHg, saline, or high levels (∼160 mmHg, angiotensin II of mean arterial pressure (MAP, n = 5-10 per group were subjected to IOP challenge (10-120 mmHg, 5 mmHg steps every 3 minutes. Electroretinograms were measured at each IOP step to assess bipolar cell (b-wave and inner retinal function (scotopic threshold response or STR. Ocular blood flow was measured using laser-Doppler flowmetry in groups with similar MAP level and the same IOP challenge protocol. Both b-wave and STR amplitudes decreased with IOP elevation. Retinal function was less susceptible to IOP challenge when MAP was high, whereas the converse was true for low MAP. Consistent with the effects on retinal function, higher IOP was needed to attenuated ocular blood flow in animals with higher MAP. The susceptibility of retinal function to IOP challenge can be ameliorated by acute high BP, and exacerbated by low BP. This is partially mediated by modifications in ocular blood flow.

  15. Straight versus tortuous retinal arteries in relation to blood pressure and genetics

    DEFF Research Database (Denmark)

    Taarnhøj, N C B B; Munch, I C; Sander, B

    2008-01-01

    dizygotic same-sex healthy twin pairs, aged 20 to 46 years, who were characterised by determination of retinal vessel diameters, arterial blood pressure, blood glucose, body mass index, smoking habits and retinal arterial tortuosity, using a three-level grading scale (straight, wavy, tortuous). Heritability......BACKGROUND/AIMS: To assess the relative influence of genetic and environmental factors on retinal arterial tortuosity and the association between tortuosity and various health indices in healthy young to middle-aged persons. METHODS: This cross-sectional study included 57 monozygotic and 52...... accounting for the remaining 18% (CI(95 )8, 36%). Increasing values of mean arterial blood pressure and body mass index were both associated with decreasing levels of retinal arterial tortuosity. CONCLUSION: There was a large variation in tortuosity of retinal arteries in these healthy subjects...

  16. Intraocular pressure, blood pressure, and retinal blood flow autoregulation: a mathematical model to clarify their relationship and clinical relevance.

    Science.gov (United States)

    Guidoboni, Giovanna; Harris, Alon; Cassani, Simone; Arciero, Julia; Siesky, Brent; Amireskandari, Annahita; Tobe, Leslie; Egan, Patrick; Januleviciene, Ingrida; Park, Joshua

    2014-05-29

    This study investigates the relationship between intraocular pressure (IOP) and retinal hemodynamics and predicts how arterial blood pressure (BP) and blood flow autoregulation (AR) influence this relationship. A mathematical model is developed to simulate blood flow in the central retinal vessels and retinal microvasculature as current flowing through a network of resistances and capacitances. Variable resistances describe active and passive diameter changes due to AR and IOP. The model is validated by using clinically measured values of retinal blood flow and velocity. The model simulations for six theoretical patients with high, normal, and low BP (HBP-, NBP-, LBP-) and functional or absent AR (-wAR, -woAR) are compared with clinical data. The model predicts that NBPwAR and HBPwAR patients can regulate retinal blood flow (RBF) as IOP varies between 15 and 23 mm Hg and between 23 and 29 mm Hg, respectively, whereas LBPwAR patients do not adequately regulate blood flow if IOP is 15 mm Hg or higher. Hemodynamic alterations would be noticeable only if IOP changes occur outside of the regulating range, which, most importantly, depend on BP. The model predictions are consistent with clinical data for IOP reduction via surgery and medications and for cases of induced IOP elevation. The theoretical model results suggest that the ability of IOP to induce noticeable changes in retinal hemodynamics depends on the levels of BP and AR of the individual. These predictions might help to explain the inconsistencies found in the clinical literature concerning the relationship between IOP and retinal hemodynamics. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  17. A novel transgenic zebrafish model for blood-brain and blood-retinal barrier development

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    Sugimoto Masahiko

    2010-07-01

    Full Text Available Abstract Background Development and maintenance of the blood-brain and blood-retinal barrier is critical for the homeostasis of brain and retinal tissue. Despite decades of research our knowledge of the formation and maintenance of the blood-brain (BBB and blood-retinal (BRB barrier is very limited. We have established an in vivo model to study the development and maintenance of these barriers by generating a transgenic zebrafish line that expresses a vitamin D-binding protein fused with enhanced green fluorescent protein (DBP-EGFP in blood plasma, as an endogenous tracer. Results The temporal establishment of the BBB and BRB was examined using this transgenic line and the results were compared with that obtained by injection of fluorescent dyes into the sinus venosus of embryos at various stages of development. We also examined the expression of claudin-5, a component of tight junctions during the first 4 days of development. We observed that the BBB of zebrafish starts to develop by 3 dpf, with expression of claudin-5 in the central arteries preceding it at 2 dpf. The hyaloid vasculature in the zebrafish retina develops a barrier function at 3 dpf, which endows the zebrafish with unique advantages for studying the BRB. Conclusion Zebrafish embryos develop BBB and BRB function simultaneously by 3 dpf, which is regulated by tight junction proteins. The Tg(l-fabp:DBP-EGFP zebrafish will have great advantages in studying development and maintenance of the blood-neural barrier, which is a new application for the widely used vertebrate model.

  18. Automatic detection of blood vessels in retinal images for diabetic retinopathy diagnosis.

    Science.gov (United States)

    Raja, D Siva Sundhara; Vasuki, S

    2015-01-01

    Diabetic retinopathy (DR) is a leading cause of vision loss in diabetic patients. DR is mainly caused due to the damage of retinal blood vessels in the diabetic patients. It is essential to detect and segment the retinal blood vessels for DR detection and diagnosis, which prevents earlier vision loss in diabetic patients. The computer aided automatic detection and segmentation of blood vessels through the elimination of optic disc (OD) region in retina are proposed in this paper. The OD region is segmented using anisotropic diffusion filter and subsequentially the retinal blood vessels are detected using mathematical binary morphological operations. The proposed methodology is tested on two different publicly available datasets and achieved 93.99% sensitivity, 98.37% specificity, 98.08% accuracy in DRIVE dataset and 93.6% sensitivity, 98.96% specificity, and 95.94% accuracy in STARE dataset, respectively.

  19. Retinal oximetry during treatment of retinal vein occlusion by ranibizumab in patients with high blood pressure and dyslipidemia.

    Science.gov (United States)

    Keilani, C; Halalchi, A; Wakpi Djeugue, D; Regis, A; Abada, S

    2016-12-01

    In the present study, we examined retinal vascular oxygen saturation in patients with retinal vein occlusion (RVO), high blood pressure (HBP) and dyslipidemia, before and during intravitreal vascular endothelial growth factor (VEGF) injection (ranibizumab). We retrospectively reviewed the medical records of six patients with visual acuity (VA) reduced by macular edema (ME) secondary to RVO with HBP and dyslipidemia, who underwent intravitreal anti-VEGF injection between October 2014 and February 2015 in the department of ophthalmology of François-Quesnay Hospital at Mantes-la-Jolie (France). The main inclusion criterion was the presence of RVO with ME and decreased VA. The primary endpoint was improvement of retinal venous oxygen saturation in patients with RVO before and 3 months after intravitreal ranibizumab injection. Secondary outcomes were improvement of retinal arterial oxygen saturation, improvement of best-corrected visual acuity (BCVA) on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, regression of ME measured by the central macular thickness (CMT) in nm and studying the correlation between blood pressure (BP) and retinal venous oxygen saturation before and after ranibizumab. Six eyes of six patients were included. Before treatment, the mean (standard deviation [SD]) of the retinal venous saturation (%) was 38.1±14.2. Three months after the injections, the mean (SD) of the retinal venous saturation (%) increased statistically significantly 49.2±11 (P=0.03). In this study, retinal venous oxygen saturation in patients with RVO, HBP and dyslipidemia was partially normalized during intravitreal ranibizumab treatment. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Improvement of retinal blood vessel detection using morphological component analysis.

    Science.gov (United States)

    Imani, Elaheh; Javidi, Malihe; Pourreza, Hamid-Reza

    2015-03-01

    Detection and quantitative measurement of variations in the retinal blood vessels can help diagnose several diseases including diabetic retinopathy. Intrinsic characteristics of abnormal retinal images make blood vessel detection difficult. The major problem with traditional vessel segmentation algorithms is producing false positive vessels in the presence of diabetic retinopathy lesions. To overcome this problem, a novel scheme for extracting retinal blood vessels based on morphological component analysis (MCA) algorithm is presented in this paper. MCA was developed based on sparse representation of signals. This algorithm assumes that each signal is a linear combination of several morphologically distinct components. In the proposed method, the MCA algorithm with appropriate transforms is adopted to separate vessels and lesions from each other. Afterwards, the Morlet Wavelet Transform is applied to enhance the retinal vessels. The final vessel map is obtained by adaptive thresholding. The performance of the proposed method is measured on the publicly available DRIVE and STARE datasets and compared with several state-of-the-art methods. An accuracy of 0.9523 and 0.9590 has been respectively achieved on the DRIVE and STARE datasets, which are not only greater than most methods, but are also superior to the second human observer's performance. The results show that the proposed method can achieve improved detection in abnormal retinal images and decrease false positive vessels in pathological regions compared to other methods. Also, the robustness of the method in the presence of noise is shown via experimental result. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Segmentation of retinal blood vessels for detection of diabetic retinopathy: A review

    Directory of Open Access Journals (Sweden)

    Rezty Amalia Aras

    2016-05-01

    Full Text Available Diabetic detinopathy (DR is effect of diabetes mellitus to the human vision that is the major cause of blindness. Early diagnosis of DR is an important requirement in diabetes treatment. Retinal fundus image is commonly used to observe the diabetic retinopathy symptoms. It can present retinal features such as blood vessel and also capture the pathologies which may lead to DR. Blood vessel is one of retinal features which can show the retina pathologies. It can be extracted from retinal image by image processing with following stages: pre-processing, segmentation, and post-processing. This paper contains a review of public retinal image dataset and several methods from various conducted researches. All discussed methods are applicable to each researcher cases. There is no further analysis to conclude the best method which can be used for general cases. However, we suggest morphological and multiscale method that gives the best accuracy in segmentation.

  2. Layer-specific blood-flow MRI of retinitis pigmentosa in RCS rats☆

    Science.gov (United States)

    Li, Guang; Garza, Bryan De La; Shih, Yen-Yu I.; Muir, Eric R.; Duong, Timothy Q.

    2013-01-01

    The Royal College of Surgeons (RCS) rat is an established animal model of retinitis pigmentosa, a family of inherited retinal diseases which starts with loss of peripheral vision and progresses to eventual blindness. Blood flow (BF), an important physiological parameter, is intricately coupled to metabolic function under normal physiological conditions and is perturbed in many neurological and retinal diseases. This study reports non-invasive high-resolution MRI (44 × 44 × 600 μm) to image quantitative retinal and choroidal BF and layer-specific retinal thicknesses in RCS rat retinas at different stages of retinal degeneration compared with age-matched controls. The unique ability to separate retinal and choroidal BF was made possible by the depth-resolved MRI technique. RBF decreased with progressive retinal degeneration, but ChBF did not change in RCS rats up to post-natal day 90. We concluded that choroidal and retinal circulations have different susceptibility to progressive retinal degeneration in RCS rats. Layer-specific retinal thickness became progressively thinner and was corroborated by histological analysis in the same animals. MRI can detect progressive anatomical and BF changes during retinal degeneration with laminar resolution. PMID:22721720

  3. Layer-specific blood-flow MRI of retinitis pigmentosa in RCS rats.

    Science.gov (United States)

    Li, Guang; De La Garza, Bryan; Shih, Yen-Yu I; Muir, Eric R; Duong, Timothy Q

    2012-08-01

    The Royal College of Surgeons (RCS) rat is an established animal model of retinitis pigmentosa, a family of inherited retinal diseases which starts with loss of peripheral vision and progresses to eventual blindness. Blood flow (BF), an important physiological parameter, is intricately coupled to metabolic function under normal physiological conditions and is perturbed in many neurological and retinal diseases. This study reports non-invasive high-resolution MRI (44 × 44 × 600 μm) to image quantitative retinal and choroidal BF and layer-specific retinal thicknesses in RCS rat retinas at different stages of retinal degeneration compared with age-matched controls. The unique ability to separate retinal and choroidal BF was made possible by the depth-resolved MRI technique. RBF decreased with progressive retinal degeneration, but ChBF did not change in RCS rats up to post-natal day 90. We concluded that choroidal and retinal circulations have different susceptibility to progressive retinal degeneration in RCS rats. Layer-specific retinal thickness became progressively thinner and was corroborated by histological analysis in the same animals. MRI can detect progressive anatomical and BF changes during retinal degeneration with laminar resolution. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Non-invasive imaging of retinal blood flow in myeloproliferative neoplasms

    DEFF Research Database (Denmark)

    Willerslev, Anne; Hansen, Mathias M; Klefter, Oliver Niels

    2017-01-01

    PURPOSE: To study the circulation in the retinal vessels in patients with blood dyscrasia due to myeloproliferative neoplasms using non-invasive retinal imaging. METHODS: Prospective consecutive case series of seven treatment-naïve patients with chronic myeloid leukaemia (n = 2), polycythemia vera...... present at baseline in patients with chronic myeloid leukaemia and were replaced by normal patterns at follow-up. Retinopathy, in the form of cotton-wool spots and retinal haemorrhages, was found at presentation in the two patients with chronic myeloid leukaemia and in one patient with polycythemia vera...

  5. 3-D segmentation of retinal blood vessels in spectral-domain OCT volumes of the optic nerve head

    Science.gov (United States)

    Lee, Kyungmoo; Abràmoff, Michael D.; Niemeijer, Meindert; Garvin, Mona K.; Sonka, Milan

    2010-03-01

    Segmentation of retinal blood vessels can provide important information for detecting and tracking retinal vascular diseases including diabetic retinopathy, arterial hypertension, arteriosclerosis and retinopathy of prematurity (ROP). Many studies on 2-D segmentation of retinal blood vessels from a variety of medical images have been performed. However, 3-D segmentation of retinal blood vessels from spectral-domain optical coherence tomography (OCT) volumes, which is capable of providing geometrically accurate vessel models, to the best of our knowledge, has not been previously studied. The purpose of this study is to develop and evaluate a method that can automatically detect 3-D retinal blood vessels from spectral-domain OCT scans centered on the optic nerve head (ONH). The proposed method utilized a fast multiscale 3-D graph search to segment retinal surfaces as well as a triangular mesh-based 3-D graph search to detect retinal blood vessels. An experiment on 30 ONH-centered OCT scans (15 right eye scans and 15 left eye scans) from 15 subjects was performed, and the mean unsigned error in 3-D of the computer segmentations compared with the independent standard obtained from a retinal specialist was 3.4 +/- 2.5 voxels (0.10 +/- 0.07 mm).

  6. Plastic roles of pericytes in the blood-retinal barrier.

    Science.gov (United States)

    Park, Do Young; Lee, Junyeop; Kim, Jaeryung; Kim, Kangsan; Hong, Seonpyo; Han, Sangyeul; Kubota, Yoshiaki; Augustin, Hellmut G; Ding, Lei; Kim, Jin Woo; Kim, Hail; He, Yulong; Adams, Ralf H; Koh, Gou Young

    2017-05-16

    The blood-retinal barrier (BRB) consists of tightly interconnected capillary endothelial cells covered with pericytes and glia, but the role of the pericytes in BRB regulation is not fully understood. Here, we show that platelet-derived growth factor (PDGF)-B/PDGF receptor beta (PDGFRβ) signalling is critical in formation and maturation of BRB through active recruitment of pericytes onto growing retinal vessels. Impaired pericyte recruitment to the vessels shows multiple vascular hallmarks of diabetic retinopathy (DR) due to BRB disruption. However, PDGF-B/PDGFRβ signalling is expendable for maintaining BRB integrity in adult mice. Although selective pericyte loss in stable adult retinal vessels surprisingly does not cause BRB disintegration, it sensitizes retinal vascular endothelial cells (ECs) to VEGF-A, leading to upregulation of angiopoietin-2 (Ang2) in ECs through FOXO1 activation and triggering a positive feedback that resembles the pathogenesis of DR. Accordingly, either blocking Ang2 or activating Tie2 greatly attenuates BRB breakdown, suggesting potential therapeutic approaches to reduce retinal damages upon DR progression.

  7. A thresholding based technique to extract retinal blood vessels from fundus images

    Directory of Open Access Journals (Sweden)

    Jyotiprava Dash

    2017-12-01

    Full Text Available Retinal imaging has become the significant tool among all the medical imaging technology, due to its capability to extract many data which is linked to various eye diseases. So, the accurate extraction of blood vessel is necessary that helps the eye care specialists and ophthalmologist to identify the diseases at the early stages. In this paper, we have proposed a computerized technique for extraction of blood vessels from fundus images. The process is conducted in three phases: (i pre-processing where the image is enhanced using contrast limited adaptive histogram equalization and median filter, (ii segmentation using mean-C thresholding to extract retinal blood vessels, (iii post-processing where morphological cleaning operation is used to remove isolated pixels. The performance of the proposed method is tested on and experimental results show that our method achieve an accuracies of 0.955 and 0.954 on Digital retinal images for vessel extraction (DRIVE and Child heart and health study in England (CHASE_DB1 databases respectively.

  8. Improvement of retinal blood vessel detection by spur removal and Gaussian matched filtering compensation

    Science.gov (United States)

    Xiao, Di; Vignarajan, Janardhan; An, Dong; Tay-Kearney, Mei-Ling; Kanagasingam, Yogi

    2016-03-01

    Retinal photography is a non-invasive and well-accepted clinical diagnosis of ocular diseases. Qualitative and quantitative assessment of retinal images is crucial in ocular diseases related clinical application. In this paper, we proposed approaches for improving the quality of blood vessel detection based on our initial blood vessel detection methods. A blood vessel spur pruning method has been developed for removing the blood vessel spurs both on vessel medial lines and binary vessel masks, which are caused by artifacts and side-effect of Gaussian matched vessel enhancement. A Gaussian matched filtering compensation method has been developed for removing incorrect vessel branches in the areas of low illumination. The proposed approaches were applied and tested on the color fundus images from one publicly available database and our diabetic retinopathy screening dataset. A preliminary result has demonstrated the robustness and good performance of the proposed approaches and their potential application for improving retinal blood vessel detection.

  9. Laser speckle imaging of rat retinal blood flow with hybrid temporal and spatial analysis method

    Science.gov (United States)

    Cheng, Haiying; Yan, Yumei; Duong, Timothy Q.

    2009-02-01

    Noninvasive monitoring of blood flow in retinal circulation will reveal the progression and treatment of ocular disorders, such as diabetic retinopathy, age-related macular degeneration and glaucoma. A non-invasive and direct BF measurement technique with high spatial-temporal resolution is needed for retinal imaging. Laser speckle imaging (LSI) is such a method. Currently, there are two analysis methods for LSI: spatial statistics LSI (SS-LSI) and temporal statistical LSI (TS-LSI). Comparing these two analysis methods, SS-LSI has higher signal to noise ratio (SNR) and TSLSI is less susceptible to artifacts from stationary speckle. We proposed a hybrid temporal and spatial analysis method (HTS-LSI) to measure the retinal blood flow. Gas challenge experiment was performed and images were analyzed by HTS-LSI. Results showed that HTS-LSI can not only remove the stationary speckle but also increase the SNR. Under 100% O2, retinal BF decreased by 20-30%. This was consistent with the results observed with laser Doppler technique. As retinal blood flow is a critical physiological parameter and its perturbation has been implicated in the early stages of many retinal diseases, HTS-LSI will be an efficient method in early detection of retina diseases.

  10. Plasmalemma Vesicle-Associated Protein Has a Key Role in Blood-Retinal Barrier Loss

    NARCIS (Netherlands)

    Wisniewska-Kruk, Joanna; van der Wijk, Anne-Eva; van Veen, Henk A.; Gorgels, Theo G. M. F.; Vogels, Ilse M. C.; Versteeg, Danielle; van Noorden, Cornelis J. F.; Schlingemann, Reinier O.; Klaassen, Ingeborg

    2016-01-01

    Loss of blood-retinal barrier (BRB) properties induced by vascular endothelial growth factor (VEGF) and other factors is an important cause of diabetic macular edema. Previously, we found that the presence of plasmalemma vesicle-associated protein (PLVAP) in retinal capillaries associates with loss

  11. Retinal hemodynamic oxygen reactivity assessed by perfusion velocity, blood oximetry and vessel diameter measurements

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Lauritsen, Anne Øberg; Larsen, Michael

    2015-01-01

    PURPOSE: To test the oxygen reactivity of a fundus photographic method of measuring macular perfusion velocity and to integrate macular perfusion velocities with measurements of retinal vessel diameters and blood oxygen saturation. METHODS: Sixteen eyes in 16 healthy volunteers were studied at two...... is a valid method for assessing macular perfusion. Results were consistent with previous observations of hyperoxic blood flow reduction using blue field entoptic and laser Doppler velocimetry. Retinal perfusion seemed to be regulated around individual set points according to blood glucose levels. Multimodal...

  12. Automatic segmentation of blood vessels from retinal fundus images ...

    Indian Academy of Sciences (India)

    The retinal blood vessels were segmented through color space conversion and color channel extraction, image pre-processing, Gabor filtering, image postprocessing, feature construction through application of principal component analysis, k-means clustering and first level classification using Naïve–Bayes classification ...

  13. Associations of blood pressure variability and retinal arteriolar diameter in participants with type 2 diabetes.

    Science.gov (United States)

    Veloudi, Panagiota; Blizzard, Leigh; Srikanth, Velandai K; McCartney, Paul; Lukoshkova, Elena V; Hughes, Alun D; Head, Geoffrey A; Sharman, James E

    2016-07-01

    Blood pressure variability is associated with macrovascular complications and stroke, but its association with the microcirculation in type II diabetes has not been assessed. This study aimed to determine the relationship between blood pressure variability indices and retinal arteriolar diameter in non-diabetic and type II diabetes participants. Digitized retinal images were analysed to quantify arteriolar diameters in 35 non-diabetic (aged 52 ± 11 years; 49% male) and 28 type II diabetes (aged 61 ± 9 years; 50% male) participants. Blood pressure variability was derived from 24-h ambulatory blood pressure. Arteriolar diameter was positively associated with daytime rate of systolic blood pressure variation (p = 0.04) among type II diabetes participants and negatively among non-diabetics (p = 0.008; interaction p = 0.001). This finding was maintained after adjusting for age, sex, body mass index and mean daytime systolic blood pressure. These findings suggest that the blood pressure variability-related mechanisms underlying retinal vascular disease may differ between people with and without type II diabetes. © The Author(s) 2016.

  14. Intravenously administered gold nanoparticles pass through the blood-retinal barrier depending on the particle size, and induce no retinal toxicity

    International Nuclear Information System (INIS)

    Kim, Jeong Hun; Kim, Jin Hyoung; Yu, Young Suk; Kim, Kyu-Won; Kim, Myung Hun

    2009-01-01

    The retina maintains homeostasis through the blood-retinal barrier (BRB). Although it is ideal to deliver the drug to the retina via systemic administration, it is still challenging due to the BRB strictly regulating permeation from blood to the retina. Herein, we demonstrated that intravenously administered gold nanoparticles could pass through the BRB and are distributed in all retinal layers without cytotoxicity. After intravenous injection of gold nanoparticles into C57BL/6 mice, 100 nm nanoparticles were not detected in the retina whereas 20 nm nanoparticles passed through the BRB and were distributed in all retinal layers. 20 nm nanoparticles in the retina were observed in neurons (75 ± 5%), endothelial cells (17 ± 6%) and peri-endothelial glial cells (8 ± 3%), where nanoparticles were bound on the membrane. In the retina, cells containing nanoparticles did not show any structural abnormality and increase of cell death compared to cells without nanoparticles. Gold nanoparticles never affected the viability of retinal endothelial cells, astrocytes and retinoblastoma cells. Furthermore, gold nanoparticles never led to any change in expression of representative biological molecules including zonula occludens-1 and glut-1 in retinal endothelial cells, neurofilaments in differentiated retinoblastoma cells and glial fibrillary acidic protein in astrocytes. Therefore, our data suggests that small gold nanoparticles (20 nm) could be an alternative for drug delivery across the BRB, which could be safely applied in vivo.

  15. Intravenously administered gold nanoparticles pass through the blood-retinal barrier depending on the particle size, and induce no retinal toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Hun; Kim, Jin Hyoung; Yu, Young Suk [Department of Ophthalmology, Seoul National University College of Medicine and Seoul Artificial Eye Center, Clinical Research Institute, Seoul National University Hospital, Seoul 151744 (Korea, Republic of); Kim, Kyu-Won [NeuroVascular Coordination Research Center, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul 151742 (Korea, Republic of); Kim, Myung Hun, E-mail: hunin315@paran.com, E-mail: ysyu@snu.ac.kr [Department of Chemistry, Yonsei University, 134 Shinchon-dong, Seodaemun-ku, Seoul 120749 (Korea, Republic of)

    2009-12-16

    The retina maintains homeostasis through the blood-retinal barrier (BRB). Although it is ideal to deliver the drug to the retina via systemic administration, it is still challenging due to the BRB strictly regulating permeation from blood to the retina. Herein, we demonstrated that intravenously administered gold nanoparticles could pass through the BRB and are distributed in all retinal layers without cytotoxicity. After intravenous injection of gold nanoparticles into C57BL/6 mice, 100 nm nanoparticles were not detected in the retina whereas 20 nm nanoparticles passed through the BRB and were distributed in all retinal layers. 20 nm nanoparticles in the retina were observed in neurons (75 {+-} 5%), endothelial cells (17 {+-} 6%) and peri-endothelial glial cells (8 {+-} 3%), where nanoparticles were bound on the membrane. In the retina, cells containing nanoparticles did not show any structural abnormality and increase of cell death compared to cells without nanoparticles. Gold nanoparticles never affected the viability of retinal endothelial cells, astrocytes and retinoblastoma cells. Furthermore, gold nanoparticles never led to any change in expression of representative biological molecules including zonula occludens-1 and glut-1 in retinal endothelial cells, neurofilaments in differentiated retinoblastoma cells and glial fibrillary acidic protein in astrocytes. Therefore, our data suggests that small gold nanoparticles (20 nm) could be an alternative for drug delivery across the BRB, which could be safely applied in vivo.

  16. Knockdown of Zebrafish Blood Vessel Epicardial Substance Results in Incomplete Retinal Lamination

    Directory of Open Access Journals (Sweden)

    Yu-Ching Wu

    2014-01-01

    Full Text Available Cell polarity during eye development determines the normal retinal lamination and differentiation of photoreceptor cells in the retina. In vertebrates, blood vessel epicardial substance (Bves is known to play an important role in the formation and maintenance of the tight junctions essential for epithelial cell polarity. In the current study, we generated a transgenic zebrafish Bves (zbves promoter-EGFP zebrafish line to investigate the expression pattern of Bves in the retina and to study the role of zbves in retinal lamination. Immunostaining with different specific antibodies from retinal cells and transmission electron microscopy were used to identify the morphological defects in normal and Bves knockdown zebrafish. In normal zebrafish, Bves is located at the apical junctions of embryonic retinal neuroepithelia during retinogenesis; later, it is strongly expressed around inner plexiform layer (IPL and retinal pigment epithelium (RPE. In contrast, a loss of normal retinal lamination and cellular polarity was found with undifferentiated photoreceptor cells in Bves knockdown zebrafish. Herein, our results indicated that disruption of Bves will result in a loss of normal retinal lamination.

  17. Blood Vessel Extraction in Color Retinal Fundus Images with Enhancement Filtering and Unsupervised Classification

    Directory of Open Access Journals (Sweden)

    Zafer Yavuz

    2017-01-01

    Full Text Available Retinal blood vessels have a significant role in the diagnosis and treatment of various retinal diseases such as diabetic retinopathy, glaucoma, arteriosclerosis, and hypertension. For this reason, retinal vasculature extraction is important in order to help specialists for the diagnosis and treatment of systematic diseases. In this paper, a novel approach is developed to extract retinal blood vessel network. Our method comprises four stages: (1 preprocessing stage in order to prepare dataset for segmentation; (2 an enhancement procedure including Gabor, Frangi, and Gauss filters obtained separately before a top-hat transform; (3 a hard and soft clustering stage which includes K-means and Fuzzy C-means (FCM in order to get binary vessel map; and (4 a postprocessing step which removes falsely segmented isolated regions. The method is tested on color retinal images obtained from STARE and DRIVE databases which are available online. As a result, Gabor filter followed by K-means clustering method achieves 95.94% and 95.71% of accuracy for STARE and DRIVE databases, respectively, which are acceptable for diagnosis systems.

  18. Total retinal detachments due to retinoblastoma: Outcomes following intra-arterial chemotherapy/ophthalmic artery chemosurgery.

    Directory of Open Access Journals (Sweden)

    Megan A Rowlands

    Full Text Available To report on the rate and timing of retinal reattachment and outcomes for retinoblastoma children who have total retinal detachments at presentation to our center and were treated with intra-arterial chemotherapy (ophthalmic artery chemosurgery, OAC.Single-center retrospective review of retinoblastoma patients who presented with total retinal detachments and were subsequently treated with OAC at MSKCC between May 2006 and July 2016. Endpoints were retinal detachment resolution, visual function, ERG amplitude, ocular survival, and patient survival from metastases.87 eyes of 84 retinoblastoma patients were included. Using a survival multistate model, by 36 months of follow-up, there was a 54% cumulative probability of complete retinal reattachment and a 76% probability of partial reattachment. 24% of eyes that completely reattached received only OAC without any prior or adjuvant treatments. Eyes that completely reattached were significantly more likely to have been diagnosed at a younger age (p<0.0001 and to have greater initial ERG values (p = 0.006. At final follow-up, 14% of eyes had gained at least 25 μV of ERG activity, and 8.0% had achieved hand motion vision or better, including one to 20/60. 13% of eyes were enucleated. No patient died from metastatic disease, and only one developed metastases.OAC can successfully treat previously considered "non-salvageable" retinoblastoma eyes with total retinal detachments, promote retinal reattachment in the majority of eyes, and preserve ocular and patient survival.

  19. An approach to localize the retinal blood vessels using bit planes and centerline detection.

    Science.gov (United States)

    Fraz, M M; Barman, S A; Remagnino, P; Hoppe, A; Basit, A; Uyyanonvara, B; Rudnicka, A R; Owen, C G

    2012-11-01

    The change in morphology, diameter, branching pattern or tortuosity of retinal blood vessels is an important indicator of various clinical disorders of the eye and the body. This paper reports an automated method for segmentation of blood vessels in retinal images. A unique combination of techniques for vessel centerlines detection and morphological bit plane slicing is presented to extract the blood vessel tree from the retinal images. The centerlines are extracted by using the first order derivative of a Gaussian filter in four orientations and then evaluation of derivative signs and average derivative values is performed. Mathematical morphology has emerged as a proficient technique for quantifying the blood vessels in the retina. The shape and orientation map of blood vessels is obtained by applying a multidirectional morphological top-hat operator with a linear structuring element followed by bit plane slicing of the vessel enhanced grayscale image. The centerlines are combined with these maps to obtain the segmented vessel tree. The methodology is tested on three publicly available databases DRIVE, STARE and MESSIDOR. The results demonstrate that the performance of the proposed algorithm is comparable with state of the art techniques in terms of accuracy, sensitivity and specificity. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Personality and Total Health Through Life Project Eye Substudy: Methodology and Baseline Retinal Features.

    Science.gov (United States)

    Wijngaarden, Peter Van; Keel, Stuart; Hodgson, Lauren A B; Kumar, Dinesh K; Aliahmad, Behzad; Paim, Cistiane C; Kiely, Kim M; Cherbuin, Nicolas; Anstey, Kaarin J; Dirani, Mohamed

    2017-01-01

    To describe the methodology and present the retinal grading findings of an older sample of australians with well-defined indices of neurocognitive function in the Personality and total Health (PATH) through life project. A cross-sectional study. Three hundred twenty-six individuals from the PatH through life project were invited to participate. Participants completed a general questionnaire and 2-field, 45-degree nonmydriatic color digital retinal photography. Photographs were graded for retinal pathology according to established protocols. Two hundred fifty-four (77.9%) subjects, aged 72 to 78 years, agreed to participate in the eye substudy. gradable images of at least 1 eye were acquired in 211 of 254 subjects (83.1%). retinal photographic screening identified 1 or more signs of pathology in 130 of the 174 subjects (74.7%) with gradable images of both eyes. a total of 45 participants (17.7%) had self-reported diabetes and diabetic retinopathy was observed in 22 (48.9%) of these participants. This well-defined sample of older australians provides a unique opportunity to interrogate associations between retinal findings, including retinal vascular geometric parameters, and indices of neurocognitive function. Copyright 2017 Asia-Pacific Academy of Ophthalmology.

  1. Compact Laser Doppler Flowmeter (LDF Fundus Camera for the Assessment of Retinal Blood Perfusion in Small Animals.

    Directory of Open Access Journals (Sweden)

    Marielle Mentek

    Full Text Available Noninvasive techniques for ocular blood perfusion assessment are of crucial importance for exploring microvascular alterations related to systemic and ocular diseases. However, few techniques adapted to rodents are available and most are invasive or not specifically focused on the optic nerve head (ONH, choroid or retinal circulation. Here we present the results obtained with a new rodent-adapted compact fundus camera based on laser Doppler flowmetry (LDF.A confocal miniature flowmeter was fixed to a specially designed 3D rotating mechanical arm and adjusted on a rodent stereotaxic table in order to accurately point the laser beam at the retinal region of interest. The linearity of the LDF measurements was assessed using a rotating Teflon wheel and a flow of microspheres in a glass capillary. In vivo reproducibility was assessed in Wistar rats with repeated measurements (inter-session and inter-day of retinal arteries and ONH blood velocity in six and ten rats, respectively. These parameters were also recorded during an acute intraocular pressure increase to 150 mmHg and after heart arrest (n = 5 rats.The perfusion measurements showed perfect linearity between LDF velocity and Teflon wheel or microsphere speed. Intraclass correlation coefficients for retinal arteries and ONH velocity (0.82 and 0.86, respectively indicated strong inter-session repeatability and stability. Inter-day reproducibility was good (0.79 and 0.7, respectively. Upon ocular blood flow cessation, the retinal artery velocity signal substantially decreased, whereas the ONH signal did not significantly vary, suggesting that it could mostly be attributed to tissue light scattering.We have demonstrated that, while not adapted for ONH blood perfusion assessment, this device allows pertinent, stable and repeatable measurements of retinal blood perfusion in rats.

  2. Does Physical Fitness Buffer the Relationship between Psychosocial Stress, Retinal Vessel Diameters, and Blood Pressure among Primary Schoolchildren?

    Science.gov (United States)

    Endes, Katharina; Herrmann, Christian; Colledge, Flora; Brand, Serge; Donath, Lars; Faude, Oliver; Pühse, Uwe; Hanssen, Henner; Zahner, Lukas

    2016-01-01

    Background. Strong evidence exists showing that psychosocial stress plays an important part in the development of cardiovascular diseases. Because physical inactivity is associated with less favourable retinal vessel diameter and blood pressure profiles, this study explores whether physical fitness is able to buffer the negative effects of psychosocial stress on retinal vessel diameters and blood pressure in young children. Methods. 325 primary schoolchildren (51% girls, Mage = 7.28 years) took part in this cross-sectional research project. Retinal arteriolar diameters, retinal venular diameters, arteriolar to venular ratio, and systolic and diastolic blood pressure were assessed in all children. Interactions terms between physical fitness (performance in the 20 m shuttle run test) and four indicators of psychosocial stress (parental reports of critical life events, family, peer and school stress) were tested in a series of hierarchical regression analyses. Results. Critical life events and family, peer, and school-related stress were only weakly associated with retinal vessel diameters and blood pressure. No support was found for a stress-buffering effect of physical fitness. Conclusion. More research is needed with different age groups to find out if and from what age physical fitness can protect against arteriolar vessel narrowing and the occurrence of other cardiovascular disease risk factors. PMID:27795958

  3. Lycium barbarum polysaccharides reduce neuronal damage, blood-retinal barrier disruption and oxidative stress in retinal ischemia/reperfusion injury.

    Directory of Open Access Journals (Sweden)

    Suk-Yee Li

    Full Text Available Neuronal cell death, glial cell activation, retinal swelling and oxidative injury are complications in retinal ischemia/reperfusion (I/R injuries. Lycium barbarum polysaccharides (LBP, extracts from the wolfberries, are good for "eye health" according to Chinese medicine. The aim of our present study is to explore the use of LBP in retinal I/R injury. Retinal I/R injury was induced by surgical occlusion of the internal carotid artery. Prior to induction of ischemia, mice were treated orally with either vehicle (PBS or LBP (1 mg/kg once a day for 1 week. Paraffin-embedded retinal sections were prepared. Viable cells were counted; apoptosis was assessed using TUNEL assay. Expression levels of glial fibrillary acidic protein (GFAP, aquaporin-4 (AQP4, poly(ADP-ribose (PAR and nitrotyrosine (NT were investigated by immunohistochemistry. The integrity of blood-retinal barrier (BRB was examined by IgG extravasations. Apoptosis and decreased viable cell count were found in the ganglion cell layer (GCL and the inner nuclear layer (INL of the vehicle-treated I/R retina. Additionally, increased retinal thickness, GFAP activation, AQP4 up-regulation, IgG extravasations and PAR expression levels were observed in the vehicle-treated I/R retina. Many of these changes were diminished or abolished in the LBP-treated I/R retina. Pre-treatment with LBP for 1 week effectively protected the retina from neuronal death, apoptosis, glial cell activation, aquaporin water channel up-regulation, disruption of BRB and oxidative stress. The present study suggests that LBP may have a neuroprotective role to play in ocular diseases for which I/R is a feature.

  4. Retinal changes in pregnancy-induced hypertension

    Directory of Open Access Journals (Sweden)

    Akash Pankaj Shah

    2015-01-01

    Full Text Available Aims: The aim was to determine the prevalence of retinal changes in pregnancy-induced hypertension (PIH and any association between the retinal changes and age, parity, blood pressure, proteinuria, and severity of the disease. Settings and Design: Hospital-based cross-sectional study. Materials and Methods: All the patients admitted with a diagnosis of PIH were included in this study. Age, gravida, gestation period, blood pressure, and proteinuria were noted from the case records. Fundus examination was done with a direct ophthalmoscope. The findings were noted and were analyzed using SPSS program. Results: A total of 150 patients of PIH were examined. The mean age of patients was 25.1 years. The gestation period ranged from 27 weeks to 42 weeks; 76 (50.67% were the primi gravida. 92 (61.33% patients had gestational hypertension, 49 (32.67% patients had preeclampsia, and 9 (6% had eclampsia. Retinal changes (hypertensive retinopathy were noted in 18 (12% patients - Grade 1 in 12 (8% and Grade 2 in 6 (4%. Hemorrhages or exudates or retinal detachment were not seen in any patient. There was statistically significant positive association of retinal changes and blood pressure (P = 0.037, proteinuria (P = 0.0005, and severity of the PIH (P = 0.004. Conclusions: Retinal changes were seen in 12% of patients with PIH. Occurrence of hypertensive retinopathy in PIH cases has been decreased due to better antenatal care and early detection and treatment of PIH cases. There is a greater chance of developing retinopathy with increase in blood pressure, severity of PIH, and proteinuria in cases of PIH.

  5. Radionuclide detection of blood-retinal barrier disruption in diabetes mellitus

    International Nuclear Information System (INIS)

    Freeman, M.L.; Barnes, W.E.; Eastman, G.; Evans, L.; Gergans, G.; Kelertas, A.; Emanuele, N.; Kaplan, E.

    1984-01-01

    Diabetic retinopathy is one of the leading causes of blindness in the United States today. Because early treatment of proliferative retinopathy offers the best chance for visual salvation, there is an essential need for methods of identifying eyes at high risk. Recent research has shown that subclinical leakage from retinal blood vessels is one of the earliest signs of retinopathy. The feasibility of using radionuclide techniques to quantitate blood-retinal barrier disruption is demonstrated by a study in which 23 diabetics and 7 nondiabetics were imaged with an Anger camera in the anterior Waters projection at 2 hours after the administration of Tc-99m DTPA. In the digitized images, regions of interest were placed over each orbit and over one of the cerebral hemispheres. Orbital counts were then compared to cerebral counts on a per pixel basis. Eye to brain ratios were found to be lowest for nondiabetics and highest for patients with proliferative retinopathy. Additionally, the dynamic analysis of the same radiopharmaceutical may allow investigators to further study the pathophysiology of the diabetic eye

  6. In-vivo imaging of blood flow in human retinal vessels using color Doppler optical coherence tomography

    Science.gov (United States)

    Yazdanfar, Siavash; Rollins, Andrew M.; Izatt, Joseph A.

    1999-04-01

    Quantification of retinal blood flow may lead to a better understanding of the progression and treatment of several ocular disorders, including diabetic retinopathy, age- related macular degeneration, and glaucoma. Current techniques, such as fluorescein angiography and laser Doppler velocimetry are limited, failing to provide sufficient information to the clinician. Color Doppler optical coherence tomography (CDOCT) is a novel technique using coherent heterodyne detection for simultaneous cross- sectional imaging of tissue microstructure and blood flow. This technique is capable of high spatial and velocity resolution imaging in highly scattering media. We implemented CDOCT for retinal blood flow mapping in human subjects. No dilation of the pupil was necessary. CDOCT is demonstrated for determining bidirectional flow in sub- 100micrometers diameter vessels in the retina. Additionally, we calculated Doppler broadening using the variance of depth- resolved spectra to identify regions with large velocity gradients within the Xenopus heart. This technique may be useful in quantifying local tissue perfusion in highly vascular retinal tissue.

  7. Oral delivery of bioencapsulated proteins across blood-brain and blood-retinal barriers.

    Science.gov (United States)

    Kohli, Neha; Westerveld, Donevan R; Ayache, Alexandra C; Verma, Amrisha; Shil, Pollob; Prasad, Tuhina; Zhu, Ping; Chan, Sic L; Li, Qiuhong; Daniell, Henry

    2014-03-01

    Delivering neurotherapeutics to target brain-associated diseases is a major challenge. Therefore, we investigated oral delivery of green fluorescence protein (GFP) or myelin basic protein (MBP) fused with the transmucosal carrier cholera toxin B subunit (CTB), expressed in chloroplasts (bioencapsulated within plant cells) to the brain and retinae of triple transgenic Alzheimer's disease (3×TgAD) mice, across the blood-brain barriers (BBB) and blood-retinal barriers (BRB). Human neuroblastoma cells internalized GFP when incubated with CTB-GFP but not with GFP alone. Oral delivery of CTB-MBP in healthy and 3×TgAD mice shows increased MBP levels in different regions of the brain, crossing intact BBB. Thioflavin S-stained amyloid plaque intensity was reduced up to 60% by CTB-MBP incubation with human AD and 3×TgAD mice brain sections ex vivo. Amyloid loads were reduced in vivo by 70% in hippocampus and cortex brain regions of 3×TgAD mice fed with bioencapsulated CTB-MBP, along with reduction in the ratio of insoluble amyloid β 42 (Aβ42) to soluble fractions. CTB-MBP oral delivery reduced Aβ42 accumulation in retinae and prevented loss of retinal ganglion cells in 3×TgAD mice. Lyophilization of leaves increased CTB-MBP concentration by 17-fold and stabilized it during long-term storage in capsules, facilitating low-cost oral delivery of therapeutic proteins across the BBB and BRB.

  8. Correlation Factor Analysis of Retinal Microvascular Changes in Patients With Essential Hypertension

    Institute of Scientific and Technical Information of China (English)

    Huang Duru; Huang Zhongning

    2006-01-01

    Objectives To investigate correlation between retinal microvascular signs and essential hypertension classification. Methods The retinal microvascular signs in patients with essential hypertension were assessed with the indirect biomicroscopy lens, the direct and the indirect ophthalmoscopes were used to determine the hypertensive retinopathy grades and retinal arteriosclerosis grades.The rank correlation analysis was used to analysis the correlation these grades with the risk factors concerned with hypertension. Results Of 72 cases with essential hypertension, 28 cases complicated with coronary disease, 20 cases diabetes, 41 cases stroke,17 cases renal malfunction. Varying extent retinal arterioscleroses were found in 71 cases, 1 case with retinal hemorrhage, 2 cases with retina edema, 4 cases with retinal hard exudation, 5 cases with retinal hemorrhage complicated by hard exudation, 2 cases with retinal hemorrhage complicated by hard exudation and cotton wool spot, 1 case with retinal hemorrhage complicated by hard exudation and microaneurysms,1 case with retinal edema and hard exudation, 1 case with retinal microaneurysms, 1 case with branch retinal vein occlusion. The rank correlation analysis showed that either hypertensive retinopathy grades or retinal arteriosclerosis grades were correlated with risk factor lamination of hypertension (r=0.25 or 0.31, P<0.05), other correlation factors included age and blood high density lipoprotein concerned about hypertensive retinopathy grades or retinal arteriosclerosis grades, but other parameters, namely systolic or diastolic pressure, total cholesterol, triglyceride, low density lipoprotein cholesterol, fasting blood glucose,blood urea nitrogen and blood creatinine were not confirmed in this correlation analysis (P > 0.05).Conclusions Either hypertensive retinopathy grade or retinal arteriosclerosis grade is close with the hypertension risk factor lamination, suggesting that the fundus examination of patients with

  9. The blood pressure-induced diameter response of retinal arterioles decreases with increasing diabetic maculopathy

    DEFF Research Database (Denmark)

    Frederiksen, Christian Alcaraz; Jeppesen, Peter; Knudsen, Søren Tang

    2006-01-01

    A consisted of normal individuals and groups B-D consisted of type 2 diabetic patients matched for diabetes duration, age, and gender, and characterized by: Group B no retinopathy, Group C mild retinopathy, Group D maculopathy not requiring laser treatment. The diameter changes of a large retinal arteriole......+/-4.5 microm), and Group C (253+/-4.4 microm), but was significantly (p=0.006) increased in Group D (279+/-5.3 microm). CONCLUSIONS: The diameter response was reduced in type 2 diabetic patients with retinopathy, whereas retinal thickness was increased in patients with diabetic maculopathy. This suggests......BACKGROUND: The aim of the study was to compare the diameter response of retinal arterioles and retinal thickness in patients with different stages of diabetic maculopathy during an increase in the arterial blood pressure. METHODS: Four groups each consisting of 19 individuals were studied. Group...

  10. New algorithm for detecting smaller retinal blood vessels in fundus images

    Science.gov (United States)

    LeAnder, Robert; Bidari, Praveen I.; Mohammed, Tauseef A.; Das, Moumita; Umbaugh, Scott E.

    2010-03-01

    About 4.1 million Americans suffer from diabetic retinopathy. To help automatically diagnose various stages of the disease, a new blood-vessel-segmentation algorithm based on spatial high-pass filtering was developed to automatically segment blood vessels, including the smaller ones, with low noise. Methods: Image database: Forty, 584 x 565-pixel images were collected from the DRIVE image database. Preprocessing: Green-band extraction was used to obtain better contrast, which facilitated better visualization of retinal blood vessels. A spatial highpass filter of mask-size 11 was applied. A histogram stretch was performed to enhance contrast. A median filter was applied to mitigate noise. At this point, the gray-scale image was converted to a binary image using a binary thresholding operation. Then, a NOT operation was performed by gray-level value inversion between 0 and 255. Postprocessing: The resulting image was AND-ed with its corresponding ring mask to remove the outer-ring (lens-edge) artifact. At this point, the above algorithm steps had extracted most of the major and minor vessels, with some intersections and bifurcations missing. Vessel segments were reintegrated using the Hough transform. Results: After applying the Hough transform, both the average peak SNR and the RMS error improved by 10%. Pratt's Figure of Merit (PFM) was decreased by 6%. Those averages were better than [1] by 10-30%. Conclusions: The new algorithm successfully preserved the details of smaller blood vessels and should prove successful as a segmentation step for automatically identifying diseases that affect retinal blood vessels.

  11. Retinal hemodynamic influence of compound xueshuantong capsule on nonproliferative diabetic retinopathy after laser photocoagulation

    Directory of Open Access Journals (Sweden)

    Yu-Yan Wang

    2014-07-01

    Full Text Available AIM: To observe retinal hemodynamic influence of compound xueshuantong capsule on nonproliferative diabetic retinopathy(NPDRafter laser photocoagulation. METHODS: A total of 41 patients(72 eyeswith NPDR after laser photocoagulation were enrolled in this study. They were all given compound xueshuantong capsule, and used color Doppler flow imaging for detection of retinal hemodynamics. RESULTS: After treatment, patients with retinal blood perfusion significantly improved; central retinal arterial peak systolic velocity(PSV, end-diastolic velocity(EDVand medial velocity(Vmwere increased, while the resistance index(RIdecreased. The difference have statistical significance(PCONCLUSION: Compound xueshuantong capsule can improve retinal blood perfusion for nonproliferative diabetic retinopathy after laser photocoagulation, which is related to improvement of visual prognosis.

  12. Consumption of Polyphenol-Rich Zingiber Zerumbet Rhizome Extracts Protects against the Breakdown of the Blood-Retinal Barrier and Retinal Inflammation Induced by Diabetes

    Directory of Open Access Journals (Sweden)

    Thing-Fong Tzeng

    2015-09-01

    Full Text Available The present study investigates the amelioration of diabetic retinopathy (DR by Zingiber zerumbet rhizome ethanol extracts (ZZRext in streptozotocin-induced diabetic rats (STZ-diabetic rats. ZZRext contains high phenolic and flavonoid contents. STZ-diabetic rats were treated orally with ZZRext (200, 300 mg/kg per day for three months. Blood-retinal barrier (BRB breakdown and increased vascular permeability were found in diabetic rats, with downregulation of occludin, and claudin-5. ZZRext treatment effectively preserved the expression of occludin, and claudin-5, leading to less BRB breakdown and less vascular permeability. Retinal histopathological observation showed that the disarrangement and reduction in thickness of retinal layers were reversed in ZZRext-treated diabetic rats. Retinal gene expression of tumor necrosis factor-α, interleukin (IL-1β, IL-6, vascular endothelial growth factor, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 were all decreased in ZZRext-treated diabetic rats. Moreover, ZZRext treatment not only inhibited the nuclear factor κB (NF-κB activation, but also downregulated the protein expression of p38 mitogen-activated protein kinase (MAPK in diabetic retina. In conclusion, the results suggest that the retinal protective effects of ZZRext occur through improved retinal structural change and inhibiting retinal inflammation. The antiretinopathy property of ZZRext might be related to the downregulation of p38 MAPK and NF-κB signal transduction induced by diabetes.

  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. Repair of Total Tractional Retinal Detachment in Norrie Disease: Report of Technique and Successful Surgical Outcome.

    Science.gov (United States)

    Todorich, Bozho; Thanos, Aristomenis; Yonekawa, Yoshihiro; Capone, Antonio

    2017-03-01

    Norrie disease is a rare, but devastating cause of pediatric retinal detachment, universally portending a poor visual prognosis. This paper describes successful surgical management of an infant with total retinal detachment associated with Norrie disease mutation. The infant was a full-term white male who presented with bilateral total funnel retinal detachments (RDs). He underwent genetic testing, which demonstrated single-point mutation 133 G>A transition in exon 2 of the NDP gene. The retinal detachment was managed with translimbal iridectomy, lensectomy, capsulectomy, and vitrectomy. Careful dissection of the retrolental membranes resulted in opening of the funnel. Single-stage surgery in this child's eye achieved re-attachment of the posterior pole with progressive reabsorption of subretinal fluid and cholesterol without the need for external drainage. Fluorescein angiography, performed at 2 months postoperatively, demonstrated perfusion of major vascular arcades, but with significant abnormalities and aneurysmal changes of higher-order vessels, suggestive of retinal and vascular dysplasia. The child has maintained brisk light perception vision. Early surgical intervention with careful dissection of tractional tissues can potentially result in good anatomic outcomes in some patients with Norrie disease-associated retinal detachment. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:260-262.]. Copyright 2017, SLACK Incorporated.

  15. A Morphological Hessian Based Approach for Retinal Blood Vessels Segmentation and Denoising Using Region Based Otsu Thresholding.

    Directory of Open Access Journals (Sweden)

    Khan BahadarKhan

    Full Text Available Diabetic Retinopathy (DR harm retinal blood vessels in the eye causing visual deficiency. The appearance and structure of blood vessels in retinal images play an essential part in the diagnoses of an eye sicknesses. We proposed a less computational unsupervised automated technique with promising results for detection of retinal vasculature by using morphological hessian based approach and region based Otsu thresholding. Contrast Limited Adaptive Histogram Equalization (CLAHE and morphological filters have been used for enhancement and to remove low frequency noise or geometrical objects, respectively. The hessian matrix and eigenvalues approach used has been in a modified form at two different scales to extract wide and thin vessel enhanced images separately. Otsu thresholding has been further applied in a novel way to classify vessel and non-vessel pixels from both enhanced images. Finally, postprocessing steps has been used to eliminate the unwanted region/segment, non-vessel pixels, disease abnormalities and noise, to obtain a final segmented image. The proposed technique has been analyzed on the openly accessible DRIVE (Digital Retinal Images for Vessel Extraction and STARE (STructured Analysis of the REtina databases along with the ground truth data that has been precisely marked by the experts.

  16. Inter-arm Blood Pressure Difference and its Relationship with Retinal Microvascular Calibres in Young Individuals: The African-PREDICT Study.

    Science.gov (United States)

    Strauss, Michél; Smith, Wayne; Schutte, Aletta E

    2016-08-01

    Bilateral systolic blood pressure (SBP) differences > 10mmHg is a common finding in clinical practice. Such BP differences in older individuals are associated with peripheral vascular disease, linked to microvascular dysfunction. Investigating retinal vessel calibres could provide insight into systemic microvascular function and may predict cardiovascular outcomes. Therefore we investigated the link between inter-arm systolic blood pressure differences (IASBPD) and the retinal microvasculature to determine the usefulness of IASBPD as an early marker of microvascular changes. In this cross-sectional study, we used data from 403 apparently healthy participants (20-30 years) (42% men; 49% black) taking part in the African-PREDICT study. Participants underwent retinal vessel imaging, anthropometric measurements and blood sampling. Brachial BP was measured sequentially in both arms to determine the mean IASBPD. Participants were stratified into two groups with an IASBPD difference in characteristics being a higher right arm SBP in the latter group (p=0.005). We found no association between IASBPD and retinal vessel calibres in any group. Less than 2% of the variance in IASBPD was explained by potential risk factors, with only SBP associating independently with IASBPD (β=115; p=0.039). In a young population an increased IASBPD is not related to retinal vessel diameters suggesting that it does not reflect early microvascular alterations. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  17. Retinal venous blood carbon monoxide response to bright light in male pigs: A preliminary study.

    Science.gov (United States)

    Oren, Dan A; Duda, Magdalena; Kozioł, Katarzyna; Romerowicz-Misielak, Maria; Koziorowska, Anna; Sołek, Przemysław; Nowak, Sławomir; Kulpa, Magdalena; Koziorowski, Marek

    2017-03-01

    The physical mechanism by which light is absorbed in the eye and has antidepressant and energizing effects in Seasonal Affective Disorder and other forms of psychiatric major depression is of scientific interest. This study was designed to explore one specific aspect of a proposed humoral phototransduction mechanism, namely that carbon monoxide (CO) levels increase in retinal venous blood in response to bright light. Eleven mature male pigs approximately six months of age were kept for 7days in darkness and fasted for 12h prior to surgery. Following mild sedation, anesthesia was induced. Silastic catheters were inserted into the dorsal nasal vein through the angular vein of the eye to reach the ophthalmic sinus, from which venous blood outflowing from the eye area was collected. The animals were exposed to 5000lx of fluorescent-generated white light. CO levels in the blood were analyzed by gas chromatography before and after 80min of light exposure. At baseline, mean CO levels in the retinal venous blood were 0.43±0.05(SE)nmol/ml. After bright light, mean CO levels increased to 0.54±0.06nmol/ml (two-tailed t-test plight exposure raises carbon monoxide levels in ophthalmic venous blood. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Retinal blood vessel extraction using tunable bandpass filter and fuzzy conditional entropy.

    Science.gov (United States)

    Sil Kar, Sudeshna; Maity, Santi P

    2016-09-01

    Extraction of blood vessels on retinal images plays a significant role for screening of different opthalmologic diseases. However, accurate extraction of the entire and individual type of vessel silhouette from the noisy images with poorly illuminated background is a complicated task. To this aim, an integrated system design platform is suggested in this work for vessel extraction using a sequential bandpass filter followed by fuzzy conditional entropy maximization on matched filter response. At first noise is eliminated from the image under consideration through curvelet based denoising. To include the fine details and the relatively less thick vessel structures, the image is passed through a bank of sequential bandpass filter structure optimized for contrast enhancement. Fuzzy conditional entropy on matched filter response is then maximized to find the set of multiple optimal thresholds to extract the different types of vessel silhouettes from the background. Differential Evolution algorithm is used to determine the optimal gain in bandpass filter and the combination of the fuzzy parameters. Using the multiple thresholds, retinal image is classified as the thick, the medium and the thin vessels including neovascularization. Performance evaluated on different publicly available retinal image databases shows that the proposed method is very efficient in identifying the diverse types of vessels. Proposed method is also efficient in extracting the abnormal and the thin blood vessels in pathological retinal images. The average values of true positive rate, false positive rate and accuracy offered by the method is 76.32%, 1.99% and 96.28%, respectively for the DRIVE database and 72.82%, 2.6% and 96.16%, respectively for the STARE database. Simulation results demonstrate that the proposed method outperforms the existing methods in detecting the various types of vessels and the neovascularization structures. The combination of curvelet transform and tunable bandpass

  19. Retinal oximetry in patients with ischaemic retinal diseases

    DEFF Research Database (Denmark)

    Rilvén, Sandra; Torp, Thomas Lee; Grauslund, Jakob

    2017-01-01

    The retinal oximeter is a new tool for non-invasive measurement of retinal oxygen saturation in humans. Several studies have investigated the associations between retinal oxygen saturation and retinal diseases. In the present systematic review, we examine whether there are associations between...... retinal oxygen saturation and retinal ischaemic diseases. We used PubMed and Embase to search for retinal oxygen saturation and retinal ischaemic diseases. Three separate searches identified a total of 79 publications. After two levels of manual screening, 10 studies were included: six about diabetic...... retinopathy (DR) and four about retinal vein occlusion. No studies about retinal artery occlusion were included. In diabetes, all studies found that increases in retinal venous oxygen saturation (rvSatO2 ) were associated with present as well as increasing levels of DR. Four of six studies also found...

  20. Relationship between blood-retinal barrier development and formation of selenite nuclear cataract in rat

    Directory of Open Access Journals (Sweden)

    Ping Lu

    2017-12-01

    Full Text Available AIM: To investigate the relationship between development of blood-retinal barrier and formation of selenite nuclear cataract in rat. METHODS: Activity of GPx, MDA level in lens and selenium content in the eyeballs of different ages rats were determined. Besides, lanthanum hydroxide \\〖La(OH3\\〗 tracer method was used to detect development status of blood-retina barrier at different ages. RESULTS: The result showed that the enzyme activity of GPx was highest in young rats before open eyes, but then decreased gradually with age. Distribution of La(OH3 in retinal pigment epithelial layer of 20-day-old rats was significantly less than 11-day-old rats. Injecting sodium selenite to 9-day-old rats, lanthanum hydroxide increased obviously and extended to the inner layers of the retina after 48h, and the retinal pigment epithelial layer was damaged seriously; while injecting sodium selenite to 18-day-old rats with the same dose, number of lanthanum hydroxide decreased significantly and did not extend to the inner layer after 48h.Before opening eyes, the content of MDA in the lens of rats was the highest, and decreased significantly after opening eyes. The Se group was 5 times as that of the control group. Besides, in these groups of rats, selenium content in the eyeballs and MDA level in the lens were in agreement with the change of La(OH3 distribution. CONCLUSION: These results indicated that antioxidant capacity in the eyelid unopened rats is not the main reason for selenite induced cataract formation. The real reason is that blood-retina barrier development is not mature in the eyelid unopened rats.

  1. Retinal biometrics based on Iterative Closest Point algorithm.

    Science.gov (United States)

    Hatanaka, Yuji; Tajima, Mikiya; Kawasaki, Ryo; Saito, Koko; Ogohara, Kazunori; Muramatsu, Chisako; Sunayama, Wataru; Fujita, Hiroshi

    2017-07-01

    The pattern of blood vessels in the eye is unique to each person because it rarely changes over time. Therefore, it is well known that retinal blood vessels are useful for biometrics. This paper describes a biometrics method using the Jaccard similarity coefficient (JSC) based on blood vessel regions in retinal image pairs. The retinal image pairs were rough matched by the center of their optic discs. Moreover, the image pairs were aligned using the Iterative Closest Point algorithm based on detailed blood vessel skeletons. For registration, perspective transform was applied to the retinal images. Finally, the pairs were classified as either correct or incorrect using the JSC of the blood vessel region in the image pairs. The proposed method was applied to temporal retinal images, which were obtained in 2009 (695 images) and 2013 (87 images). The 87 images acquired in 2013 were all from persons already examined in 2009. The accuracy of the proposed method reached 100%.

  2. Cytomegalovirus glycoprotein B genotyping in ocular fluids and blood of AIDS patients with cytomegalovirus retinitis

    NARCIS (Netherlands)

    Peek, R.; Verbraak, F.; Bruinenberg, M.; van der Lelij, A.; van den Horn, G.; Kijlstra, A.

    1998-01-01

    To determine the frequency of cytomegalovirus glycoprotein B (gB) genotypes in clinical samples of ocular fluids of patients with acquired immune deficiency syndrome (AIDS) who have cytomegalovirus retinitis and to compare these with the cytomegalovirus gB genotype in paired peripheral blood

  3. Ocular hemodynamics in patients with rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    N. H. Zavgorodnya

    2014-10-01

    Full Text Available Aim. In case of retinal detachment atrophic processes lead to irreversible loss of functions within 4–6 days, it happens on underlying low ocular blood flow. In order to evaluate the degree of violation of regional hemodynamics in patients with retinal detachment two groups of patients were examined: the main group (52 patients with rhegmatogenous retinal detachment and the control group (24 myopic patients with lattice form of peripheral chorioretinal dystrophy. Methods and results. Doppler and reography results had been compared, significant decrease of blood flow in patients with retinal detachment was found. No differences between affected and fellow eye in these patients, close negative correlation between the level of ocular blood flow and the degree of myopia in the control group. Conclusion. This demonstrates the feasibility of actions to improve regional blood flow in patients operated on for retinal detachment.

  4. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

    Traustason, Sindri; Kiilgaard, Jens Folke; Karlsson, Robert

    2013-01-01

    PURPOSE: To assess the validity of spectrophotometric retinal oximetry, by comparison to blood gas analysis and intra-vitreal measurements of partial pressure of oxygen (pO2). METHODS: Female domestic pigs were used for all experiments (n=8). Oxygen fraction in inspired air was changed using...... a mixture of room air, pure oxygen and pure nitrogen, ranging from 5% to 100% oxygen. Femoral arterial blood gas analysis and retinal oximetry was performed at each level of inspiratory oxygen fraction. Retinal oximetry was performed using a commercial instrument, the Oxymap Retinal Oximeter T1 (Oxymap ehf...... arterial oxygen saturation and the optical density ratio over retinal arteries revealed an approximately linear relationship (R(2) = 0.74, p = 3.4 x 10(-9)). In order to test the validity of applying the arterial calibration to veins, we compared non-invasive oximetry measurements to invasive pO2...

  5. Protein kinase C in porcine retinal arteries and neuroretina following retinal ischemia-reperfusion

    DEFF Research Database (Denmark)

    Gesslein, Bodil; Gustafsson, Lotta; Wackenfors, Angelica

    2009-01-01

    Identification of the intracellular signal-transduction pathways activated in retinal ischemia may be important in revealing novel pharmacological targets. To date, most studies have focused on identifying neuroprotective agents. The retinal blood vessels are key organs in circulatory failure, an...

  6. Bloodstream-To-Eye Infections Are Facilitated by Outer Blood-Retinal Barrier Dysfunction.

    Directory of Open Access Journals (Sweden)

    Phillip S Coburn

    Full Text Available The blood-retinal barrier (BRB functions to maintain the immune privilege of the eye, which is necessary for normal vision. The outer BRB is formed by tightly-associated retinal pigment epithelial (RPE cells which limit transport within the retinal environment, maintaining retinal function and viability. Retinal microvascular complications and RPE dysfunction resulting from diabetes and diabetic retinopathy cause permeability changes in the BRB that compromise barrier function. Diabetes is the major predisposing condition underlying endogenous bacterial endophthalmitis (EBE, a blinding intraocular infection resulting from bacterial invasion of the eye from the bloodstream. However, significant numbers of EBE cases occur in non-diabetics. In this work, we hypothesized that dysfunction of the outer BRB may be associated with EBE development. To disrupt the RPE component of the outer BRB in vivo, sodium iodate (NaIO3 was administered to C57BL/6J mice. NaIO3-treated and untreated mice were intravenously injected with 108 colony forming units (cfu of Staphylococcus aureus or Klebsiella pneumoniae. At 4 and 6 days postinfection, EBE was observed in NaIO3-treated mice after infection with K. pneumoniae and S. aureus, although the incidence was higher following S. aureus infection. Invasion of the eye was observed in control mice following S. aureus infection, but not in control mice following K. pneumoniae infection. Immunohistochemistry and FITC-dextran conjugate transmigration assays of human RPE barriers after infection with an exoprotein-deficient agr/sar mutant of S. aureus suggested that S. aureus exoproteins may be required for the loss of the tight junction protein, ZO-1, and for permeability of this in vitro barrier. Our results support the clinical findings that for both pathogens, complications which result in BRB permeability increase the likelihood of bacterial transmigration from the bloodstream into the eye. For S. aureus, however, BRB

  7. Retinal Macroglial Responses in Health and Disease

    Directory of Open Access Journals (Sweden)

    Rosa de Hoz

    2016-01-01

    Full Text Available Due to their permanent and close proximity to neurons, glial cells perform essential tasks for the normal physiology of the retina. Astrocytes and Müller cells (retinal macroglia provide physical support to neurons and supplement them with several metabolites and growth factors. Macroglia are involved in maintaining the homeostasis of extracellular ions and neurotransmitters, are essential for information processing in neural circuits, participate in retinal glucose metabolism and in removing metabolic waste products, regulate local blood flow, induce the blood-retinal barrier (BRB, play fundamental roles in local immune response, and protect neurons from oxidative damage. In response to polyetiological insults, glia cells react with a process called reactive gliosis, seeking to maintain retinal homeostasis. When malfunctioning, macroglial cells can become primary pathogenic elements. A reactive gliosis has been described in different retinal pathologies, including age-related macular degeneration (AMD, diabetes, glaucoma, retinal detachment, or retinitis pigmentosa. A better understanding of the dual, neuroprotective, or cytotoxic effect of macroglial involvement in retinal pathologies would help in treating the physiopathology of these diseases. The extensive participation of the macroglia in retinal diseases points to these cells as innovative targets for new drug therapies.

  8. Genetic determinants of hyaloid and retinal vasculature in zebrafish

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    Hyde David R

    2007-10-01

    Full Text Available Abstract Background The retinal vasculature is a capillary network of blood vessels that nourishes the inner retina of most mammals. Developmental abnormalities or microvascular complications in the retinal vasculature result in severe human eye diseases that lead to blindness. To exploit the advantages of zebrafish for genetic, developmental and pharmacological studies of retinal vasculature, we characterised the intraocular vasculature in zebrafish. Results We show a detailed morphological and developmental analysis of the retinal blood supply in zebrafish. Similar to the transient hyaloid vasculature in mammalian embryos, vessels are first found attached to the zebrafish lens at 2.5 days post fertilisation. These vessels progressively lose contact with the lens and by 30 days post fertilisation adhere to the inner limiting membrane of the juvenile retina. Ultrastructure analysis shows these vessels to exhibit distinctive hallmarks of mammalian retinal vasculature. For example, smooth muscle actin-expressing pericytes are ensheathed by the basal lamina of the blood vessel, and vesicle vacuolar organelles (VVO, subcellular mediators of vessel-retinal nourishment, are present. Finally, we identify 9 genes with cell membrane, extracellular matrix and unknown identity that are necessary for zebrafish hyaloid and retinal vasculature development. Conclusion Zebrafish have a retinal blood supply with a characteristic developmental and adult morphology. Abnormalities of these intraocular vessels are easily observed, enabling application of genetic and chemical approaches in zebrafish to identify molecular regulators of hyaloid and retinal vasculature in development and disease.

  9. Automated artery-venous classification of retinal blood vessels based on structural mapping method

    Science.gov (United States)

    Joshi, Vinayak S.; Garvin, Mona K.; Reinhardt, Joseph M.; Abramoff, Michael D.

    2012-03-01

    Retinal blood vessels show morphologic modifications in response to various retinopathies. However, the specific responses exhibited by arteries and veins may provide a precise diagnostic information, i.e., a diabetic retinopathy may be detected more accurately with the venous dilatation instead of average vessel dilatation. In order to analyze the vessel type specific morphologic modifications, the classification of a vessel network into arteries and veins is required. We previously described a method for identification and separation of retinal vessel trees; i.e. structural mapping. Therefore, we propose the artery-venous classification based on structural mapping and identification of color properties prominent to the vessel types. The mean and standard deviation of each of green channel intensity and hue channel intensity are analyzed in a region of interest around each centerline pixel of a vessel. Using the vector of color properties extracted from each centerline pixel, it is classified into one of the two clusters (artery and vein), obtained by the fuzzy-C-means clustering. According to the proportion of clustered centerline pixels in a particular vessel, and utilizing the artery-venous crossing property of retinal vessels, each vessel is assigned a label of an artery or a vein. The classification results are compared with the manually annotated ground truth (gold standard). We applied the proposed method to a dataset of 15 retinal color fundus images resulting in an accuracy of 88.28% correctly classified vessel pixels. The automated classification results match well with the gold standard suggesting its potential in artery-venous classification and the respective morphology analysis.

  10. Quantitative retinal and choroidal blood flow during light, dark adaptation and flicker light stimulation in rats using fluorescent microspheres.

    Science.gov (United States)

    Shih, Yen-Yu I; Wang, Lin; De La Garza, Bryan H; Li, Guang; Cull, Grant; Kiel, Jeffery W; Duong, Timothy Q

    2013-02-01

    The present study aimed to quantify retinal and choroidal blood flow (BF) during light, dark adaptation and flicker light stimulation using the microsphere technique. Adult male Sprague-Dawley rats were anesthetized with isoflurane. Eyes were dark (Group I, n = 8), light (Group II, n = 8) adapted or stimulated with 10 Hz flicker light (Group III, n = 10). Retinal and choroidal BF were measured by a previously established method, using a mixture of 8 µm yellow-green and 10 µm red fluorescent microspheres. The microspheres were counted ex vivo in the dissected retina and choroid and in the reference arterial blood under a fluorescent microscope. The choroidal BF was 64.8 ± 29 µl/min (mean ± SD) during dark adaptation, not significantly different from that during light adaptation (66.0 ± 17.8 µl/min). The retinal BF was 13.5 ± 3.2 µl/min during 10 Hz flickering light stimulation, significantly higher than that during dark adaptation in the control fellow eyes (9.9 ± 2.9 µl/min). The choroidal BF values were not statistically different between flicker stimulation and dark adaptation. Retinal BF was 11.6 ± 2.9 µl/min during light adaptation. Dark adaptation did not increase retinal BF (Group I, 8.2 ± 2.4 µl/min; Group II, 9.9 ± 2.9 µl/min). These findings argue against a dark-induced or flicker-induced functional hyperemia in the choroid as a result of the demands of the outer retina. Retinal BF was not higher during dark adaptation. Our data support the conclusion that the inner retina has a higher energy demand in flicker conditions relative to dark.

  11. Segmentation of retinal blood vessels using artificial neural networks for early detection of diabetic retinopathy

    Science.gov (United States)

    Mann, Kulwinder S.; Kaur, Sukhpreet

    2017-06-01

    There are various eye diseases in the patients suffering from the diabetes which includes Diabetic Retinopathy, Glaucoma, Hypertension etc. These all are the most common sight threatening eye diseases due to the changes in the blood vessel structure. The proposed method using supervised methods concluded that the segmentation of the retinal blood vessels can be performed accurately using neural networks training. It uses features which include Gray level features; Moment Invariant based features, Gabor filtering, Intensity feature, Vesselness feature for feature vector computation. Then the feature vector is calculated using only the prominent features.

  12. Vasoinhibins regulate the inner and outer blood-retinal barrier and limit retinal oxidative stress.

    Science.gov (United States)

    Arredondo Zamarripa, David; Díaz-Lezama, Nundehui; Meléndez García, Rodrigo; Chávez Balderas, Jesús; Adán, Norma; Ledesma-Colunga, Maria G; Arnold, Edith; Clapp, Carmen; Thebault, Stéphanie

    2014-01-01

    Vasoinhibins are prolactin fragments present in the retina, where they have been shown to prevent the hypervasopermeability associated with diabetes. Enhanced bradykinin (BK) production contributes to the increased transport through the blood-retina barrier (BRB) in diabetes. Here, we studied if vasoinhibins regulate BRB permeability by targeting the vascular endothelium and retinal pigment epithelium (RPE) components of this barrier. Intravitreal injection of BK in male rats increased BRB permeability. Vasoinhibins prevented this effect, as did the B2 receptor antagonist Hoe-140. BK induced a transient decrease in mouse retinal and brain capillary endothelial monolayer resistance that was blocked by vasoinhibins. Both vasoinhibins and the nitric oxide (NO) synthase inhibitor L-NAME, but not the antioxidant N-acetyl cysteine (NAC), blocked the transient decrease in bovine umbilical vein endothelial cell (BUVEC) monolayer resistance induced by BK; this block was reversed by the NO donor DETANONOate. Vasoinhibins also prevented the BK-induced actin cytoskeleton redistribution, as did L-NAME. BK transiently decreased human RPE (ARPE-19) cell monolayer resistance, and this effect was blocked by vasoinhibins, L-NAME, and NAC. DETANONOate reverted the blocking effect of vasoinhibins. Similar to BK, the radical initiator Luperox induced a reduction in ARPE-19 cell monolayer resistance, which was prevented by vasoinhibins. These effects on RPE resistance coincided with actin cytoskeleton redistribution. Intravitreal injection of vasoinhibins reduced the levels of reactive oxygen species (ROS) in retinas of streptozotocin-induced diabetic rats, particularly in the RPE and capillary-containing layers. Thus, vasoinhibins reduce BRB permeability by targeting both its main inner and outer components through NO- and ROS-dependent pathways, offering potential treatment strategies against diabetic retinopathies.

  13. Vasoinhibins regulate the inner and outer blood-retinal barrier and limit retinal oxidative stress

    Directory of Open Access Journals (Sweden)

    David eArredondo Zamarripa

    2014-10-01

    Full Text Available Vasoinhibins are prolactin fragments present in the retina, where they have been shown to prevent the hypervasopermeability associated with diabetes. Enhanced bradykinin (BK production contributes to the increased transport through the blood-retina barrier (BRB in diabetes. Here, we studied if vasoinhibins regulate BRB permeability by targeting the vascular endothelium and retinal pigment epithelium (RPE components of this barrier. Intravitreal injection of BK in male rats increased BRB permeability. Vasoinhibins prevented this effect, as did the B2 receptor antagonist Hoe-140. BK induced a transient decrease in mouse retinal and brain capillary endothelial monolayer resistance that was blocked by vasoinhibins. Both vasoinhibins and the nitric oxide (NO synthase inhibitor L-NAME, but not the antioxidant N-acetyl cysteine (NAC, blocked the transient decrease in bovine umbilical vein endothelial cell (BUVEC monolayer resistance induced by BK; this block was reversed by the NO donor DETANONOate. Vasoinhibins also prevented the BK-induced actin cytoskeleton redistribution, as did L-NAME. BK transiently decreased human RPE (ARPE-19 cell monolayer resistance, and this effect was blocked by vasoinhibins, L-NAME, and NAC. DETANONOate reverted the blocking effect of vasoinhibins. Similar to BK, the radical initiator Luperox induced a reduction in ARPE-19 cell monolayer resistance, which was prevented by vasoinhibins. These effects on RPE resistance coincided with actin cytoskeleton redistribution. Intravitreal injection of vasoinhibins reduced the levels of reactive oxygen species (ROS in retinas of streptozotocin-induced diabetic rats, particularly in the RPE and capillary-containing layers. Thus, vasoinhibins reduce BRB permeability by targeting both its main inner and outer components through NO- and ROS-dependent pathways, offering potential treatment strategies against diabetic retinopathies.

  14. Zika virus infection of cellular components of the blood-retinal barriers: implications for viral associated congenital ocular disease.

    Science.gov (United States)

    Roach, Tracoyia; Alcendor, Donald J

    2017-03-03

    Ocular abnormalities present in microcephalic infants with presumed Zika virus (ZIKV) congenital disease includes focal pigment mottling of the retina, chorioretinal atrophy, optic nerve abnormalities, and lens dislocation. Target cells in the ocular compartment for ZIKV infectivity are unknown. The cellular response of ocular cells to ZIKV infection has not been described. Mechanisms for viral dissemination in the ocular compartment of ZIKV-infected infants and adults have not been reported. Here, we identify target cells for ZIKV infectivity in both the inner and outer blood-retinal barriers (IBRB and OBRB), describe the cytokine expression profile in the IBRB after ZIKV exposure, and propose a mechanism for viral dissemination in the retina. We expose primary cellular components of the IBRB including human retinal microvascular endothelial cells, retinal pericytes, and Müller cells as well as retinal pigmented epithelial cells of the OBRB to the PRVABC56 strain of ZIKV. Viral infectivity was analyzed by microscopy, immunofluorescence, and reverse transcription polymerase chain reaction (RT-PCR and qRT-PCR). Angiogenic and proinflammatory cytokines were measured by Luminex assays. We find by immunofluorescent staining using the Flavivirus 4G2 monoclonal antibody that retinal endothelial cells and pericytes of the IBRB and retinal pigmented epithelial cells of the OBRB are fully permissive for ZIKV infection but not Müller cells when compared to mock-infected controls. We confirmed ZIKV infectivity in retinal endothelial cells, retinal pericytes, and retinal pigmented epithelial cells by RT-PCR and qRT-PCR using ZIKV-specific oligonucleotide primers. Expression profiles by Luminex assays in retinal endothelial cells infected with ZIKV revealed a marginal increase in levels of beta-2 microglobulin (β2-m), granulocyte macrophage colony-stimulating factor (GMCSF), intercellular adhesion molecule 1 (ICAM-1), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP

  15. Improvement in retinal venous oxygen saturation after panretinal photocoagulation is predictive of progression of proliferative diabetic retinopathy

    DEFF Research Database (Denmark)

    Torp, Thomas Lee; Kawasaki, Ryo; Wong, Tien Yin

    blood pressure was 152/84mmHg. Retinal arterial and venous saturation was 96.7% and 67.4%, respectively. Patients in Group 1 and 2 did not differ in baseline retinal arterial and venous oxygen saturation, number of laser spots delivered, total laser energy delivered, or change in retinal arterial oxygen...... patients with diagnosed PDR were included. We performed wide-field fluorescein angiography (WFA) (Optomap; Optos PLC., Dunfermline, Scotland, UK) and retinal oximetry (Oxymap model T1; Oxymap, software version 2.4.2, Reykjavik, Iceland) at baseline and three months after PRP by a navigated laser (NAVILAS...

  16. EFFECTUAL HUMAN AUTHENTICATION FOR CRITICAL SECURITY APPLICATIONS USING RETINAL IMAGES

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    L. Latha

    2010-11-01

    Full Text Available A robust method of human authentication based on the retinal blood vessel pattern is presented in this paper. This method entails a segmentation process to identify retinal blood vessel pattern, template generation consisting of the bifurcation points in the retina and matching of the intersection points in the template patterns. The number of matched blood vessel intersection points between the two patterns compared is used as a measure of similarity. As Liveness detection is a highly desirable anti-spoofing measure in biometric authentication, it is ensured while acquiring retinal images in realtime. The validity of our approach is verified with experimental results obtained from 603 comparisons made using 303 retinal images from three different publicly available databases, namely DRIVE, VARIA and STARE. We found that the proposed retinal recognition method gives 100%, 96.3% and 91.1% recognition rates respectively for the above databases. To the best of our knowledge, this is the first work that uses a large number of retinal images from different retinal databases for the authentication purpose.

  17. Upregulated inflammatory associated factors and blood-retinal barrier changes in the retina of type 2 diabetes mellitus model

    Directory of Open Access Journals (Sweden)

    Rui-Jin Ran

    2016-11-01

    Full Text Available AIM: To examine the expression of high mobility group box-1 (HMGB-1 and intercellular adhesion molecule-1 (ICAM-1 in the retina and the hippocampal tissues; and further to evaluate the association of these two molecules with the alterations of blood-retinal barrier (BRB and blood-brain barrier (BBB in a rat model of type 2 diabetes. METHODS: The type-2 diabetes mellitus (DM model was established with a high-fat and high-glucose diet combined with streptozotocin (STZ. Sixteen weeks after DM induction, morphological changes of retina and hippocampus were observed with hematoxylin-eosin staining, and alternations of BRB and BBB permeability were measured using Evans blue method. Levels of HMGB-1 and ICAM-1 in retina and hippocampus were detected by Western blot. Serum HMGB-1 levels were determined by enzyme-linked immunosorbent assay (ELISA. RESULTS: A significantly higher serum fasting blood glucose level in DM rats was observed 2wk after STZ injection (P<0.01. The serum levels of fasting insulin, Insulin resistance homeostatic model assessment (IRHOMA, total cholesterol (TC, total triglycerides (TG and low density lipoprotein cholesterol (LDL-C in the DM rats significantly higher than those in the controls (all P<0.01. HMGB-1 (0.96±0.03, P<0.01 and ICAM-1 (0.76±0.12, P<0.05 levels in the retina in the DM rats were significantly higher than those in the controls. HMGB-1 (0.83±0.13, P<0.01 and ICAM-1 (1.15±0.08, P<0.01 levels in the hippocampal tissues in the DM rats were also significantly higher than those in the controls. Sixteen weeks after induction of DM, the BRB permeability to albumin-bound Evans blue dye in the DM rats was significantly higher than that in the controls (P<0.01. However, there was no difference of BBB permeability between the DM rats and controls. When compared to the controls, hematoxylin and eosin staining showed obvious irregularities in the DM rats. CONCLUSION: BRB permeability increases significantly

  18. 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.

  19. Retinal vascular calibres are significantly associated with cardiovascular risk factors

    DEFF Research Database (Denmark)

    von Hanno, T.; Bertelsen, G.; Sjølie, Anne K.

    2014-01-01

    . Association between retinal vessel calibre and the cardiovascular risk factors was assessed by multivariable linear and logistic regression analyses. Results: Retinal arteriolar calibre was independently associated with age, blood pressure, HbA1c and smoking in women and men, and with HDL cholesterol in men......Purpose: To describe the association between retinal vascular calibres and cardiovascular risk factors. Methods: Population-based cross-sectional study including 6353 participants of the TromsO Eye Study in Norway aged 38-87years. Retinal arteriolar calibre (central retinal artery equivalent...... cardiovascular risk factors were independently associated with retinal vascular calibre, with stronger effect of HDL cholesterol and BMI in men than in women. Blood pressure and smoking contributed most to the explained variance....

  20. Changes in Retinal and Choroidal Vascular Blood Flow after Oral Sildenafil: An Optical Coherence Tomography Angiography Study

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    David Berrones

    2017-01-01

    Full Text Available Purpose. To describe changes in the retina and choroidal flow by optical coherence tomography angiography (OCT-A after a single dose of oral sildenafil. Method. A case-control study. Patients in the study group received 50 mg of oral sildenafil. Patients in the control group received a sham pill. Retinal and choroidal images were obtained at baseline (before pill ingestion and 1 hour after ingestion. Central macular and choroidal thickness, choroidal and outer retina flow, and the retinal and choroidal vascular density were compared using a Mann-Whitney U test. Results. Twenty eyes were enrolled into the study group and 10 eyes in the control group. There was a significant difference in central choroidal thickness and outer retina blood flow between groups after 1 hour of sildenafil ingestion (p<0.01. There were no differences in central macular thickness, choroidal flow, and retinal vascular density among groups. Conclusions. A single dose of oral sildenafil increases choroidal thickness, probably due to sildenafil-induced vasodilation.

  1. Clinical application of OCTA in observation of macular blood flow density in patients with diabetic retinopathy

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    Xiang Xiang

    2017-07-01

    Full Text Available AIM: Using optical coherence tomography angiography(OCTAto observe the changes and clinical significance of macular blood flow density in patients with diabetic retinopathy(DR.METHODS: Totally 47 eyes(28 patientswith diabetic retinopathy(DRwere enrolled in the DR group. According to the international clinical grading criteria of diabetic retinopathy, 30 eyes(19 patientswith non-proliferative diabetic retinopathy were classified as the NPDR group, and 17 eyes(11 patientswith proliferative diabetic retinopathy were classified as PDR group. A total of 46(27 subjectshealthy eyes with matched age were enrolled in the control group. All the subjects underwent the 3mm×3mm scanning of macular retina by optical coherence tomography angiography(OCTA, obtaining 4 levels of macular blood flow density map. The macular blood flow density at 3 levels, including superficial retinal layer, deep retinal layer and choroidal capillaries layer, were measured. RESULTS: The macular blood flow density of superfical retinal layer, deep retinal layer and choroidal capillaries layer in DR group were 0.4963±0.0840, 0.4798±0.0801 and 0.5290±0.0528, respectively. Among them, the blood flow density of each layer were 0.5064±0.0843,0.4983±0.0766,0.5345±0.0529, respectively, for the NPDR group, and were 0.4786±0.0830, 0.4473±0.0778,0.5192±0.0526, respectively, for the PDR group. For the control group, the density of each layers were 0.5919±0.0704, 0.6301±0.0527, 0.5691±0.0169, respectively. The macular blood flow density was significantly different in the superficial retinal layer, deep retinal layer and choroidal capillary layer between the control group and the NPDR group, as well as the PDR group and the DR group(total PP=0.029, but not in the superficial retina layer and choroid capillary layer(P=0.236, 0.268. CONCLUSION: Compared with the control group, the macular blood flow density of superficial retinal layer, deep retinal layer and choroidal capillary

  2. Concurrent OCT imaging of stimulus evoked retinal neural activation and hemodynamic responses

    Science.gov (United States)

    Son, Taeyoon; Wang, Benquan; Lu, Yiming; Chen, Yanjun; Cao, Dingcai; Yao, Xincheng

    2017-02-01

    It is well established that major retinal diseases involve distortions of the retinal neural physiology and blood vascular structures. However, the details of distortions in retinal neurovascular coupling associated with major eye diseases are not well understood. In this study, a multi-modal optical coherence tomography (OCT) imaging system was developed to enable concurrent imaging of retinal neural activity and vascular hemodynamics. Flicker light stimulation was applied to mouse retinas to evoke retinal neural responses and hemodynamic changes. The OCT images were acquired continuously during the pre-stimulation, light-stimulation, and post-stimulation phases. Stimulus-evoked intrinsic optical signals (IOSs) and hemodynamic changes were observed over time in blood-free and blood regions, respectively. Rapid IOSs change occurred almost immediately after stimulation. Both positive and negative signals were observed in adjacent retinal areas. The hemodynamic changes showed time delays after stimulation. The signal magnitudes induced by light stimulation were observed in blood regions and did not show significant changes in blood-free regions. These differences may arise from different mechanisms in blood vessels and neural tissues in response to light stimulation. These characteristics agreed well with our previous observations in mouse retinas. Further development of the multimodal OCT may provide a new imaging method for studying how retinal structures and metabolic and neural functions are affected by age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and other diseases, which promises novel noninvasive biomarkers for early disease detection and reliable treatment evaluations of eye diseases.

  3. Clinical reference value of retinal microvascular changes in patients with cerebral microbleeds

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    Ji-Yuan Guo

    2014-12-01

    Full Text Available AIM: To study clinical reference value of retinal microvascular changes in patients with cerebral microbleeds(CMBsand discuss its clinical significance. METHODS:From January 2012 to December 2013, 125 hospitalized patients were collected, including 81 cases were male, 44 cases were female, mean age 76.3±11.2 years old. For all patients, functions of liver and kidney, blood-lipoids, blood sugar and blood biochemical examination were tested, and fundus photography and cerebral MR was done. According to the fundus camera eyes, retinal arteriolar equivalent(RAE, retinal venular equivalent(RVE, retinal vein diameter ratio(AVRand arteriovenous crossing sign(AVNwere identified, CMBs were classified with cerebral MRI. All the data were processed by SPSS statistical software. RESULTS: The central retinal arteriolar equivalent(CRAE, central retinal venular equivalent(CRVEand AVR values in the eyes were found no statistical difference(PPCOCLUSION: The results show that retinal microvascular changes, especially small retinal vein arteriovenous cross width, and arteriovenous crossing phenomenon, in which CMBs will happen more likely. After sex, age, hypertension and hyperglycemia in patients with traditional cardiovascular risk factors being ruled out, the retinal microvascular changes are still relatively factors of CMB's occurrence.

  4. Autologous blood transfusion in total knee replacement surgery.

    Science.gov (United States)

    Sarkanović, Mirka Lukić; Gvozdenović, Ljiljana; Savić, Dragan; Ilić, Miroslav P; Jovanović, Gordana

    2013-03-01

    Total knee replacement (TKR) surgery is one of the most frequent and the most extensive procedures in orthopedic surgery, accompanied with some serious complications. Perioperative blood loss is one of the most serious losses, so it is vital to recognize and treat such losses properly. Autologous blood transfusion is the only true alternative for the allogeneic blood. The aim of this study was to to examine if autologous blood transfusion reduces usage of allogenic blood in total knee replacement surgery, as well as to examine possible effect of autologous blood transfusion on postoperative complications, recovery and hospital stay of patients after total knee replacement surgery. During the controlled, prospective, randomised study we compared two groups of patients (n = 112) with total prosthesis implanted in their knee. The group I consisted of the patients who received the transfusion of other people's (allogeneic) blood (n = 57) and the group II of the patients whose blood was collected postoperatively and then given them [their own (autologous) blood] (n = 55). The transfusion trigger for both groups was hemoglobin level of 85 g/L. In the group of patients whose blood was collected perioperatively only 9 (0.9%) of the patients received transfusion of allogeneic blood, as opposed to the control group in which 98.24% of the patients received the transfusion of allogeneic blood (p blood was collected stayed in hospital for 6.18 days, while the patients of the control group stayed 7.67 days (p blood transfusion is a very effective method for reducing consumption of allogenic blood and thus, indirectly for reducing all complications related to allogenic blood transfusion. There is also a positive influence on postoperative recovery after total knee replacement surgery due to the reduction of hospital stay, and indirectly on the reduction of hospital costs.

  5. Placental Growth Factor Contributes to Micro-Vascular Abnormalization and Blood-Retinal Barrier Breakdown in Diabetic Retinopathy

    Science.gov (United States)

    Kowalczuk, Laura; Touchard, Elodie; Omri, Samy; Jonet, Laurent; Klein, Christophe; Valamanes, Fatemeh; Berdugo, Marianne; Bigey, Pascal; Massin, Pascale; Jeanny, Jean-Claude; Behar-Cohen, Francine

    2011-01-01

    Objective There are controversies regarding the pro-angiogenic activity of placental growth factor (PGF) in diabetic retinopathy (DR). For a better understanding of its role on the retina, we have evaluated the effect of a sustained PGF over-expression in rat ocular media, using ciliary muscle electrotransfer (ET) of a plasmid encoding rat PGF-1 (pVAX2-rPGF-1). Materials and Methods pVAX2-rPGF-1 ET in the ciliary muscle (200 V/cm) was achieved in non diabetic and diabetic rat eyes. Control eyes received saline or naked plasmid ET. Clinical follow up was carried out over three months using slit lamp examination and fluorescein angiography. After the control of rPGF-1 expression, PGF-induced effects on retinal vasculature and on the blood-external barrier were evaluated respectively by lectin and occludin staining on flat-mounts. Ocular structures were visualized through histological analysis. Results After fifteen days of rPGF-1 over-expression in normal eyes, tortuous and dilated capillaries were observed. At one month, microaneurysms and moderate vascular sprouts were detected in mid retinal periphery in vivo and on retinal flat-mounts. At later stages, retinal pigmented epithelial cells demonstrated morphological abnormalities and junction ruptures. In diabetic retinas, PGF expression rose between 2 and 5 months, and, one month after ET, rPGF-1 over-expression induced glial activation and proliferation. Conclusion This is the first demonstration that sustained intraocular PGF production induces vascular and retinal changes similar to those observed in the early stages of diabetic retinopathy. PGF and its receptor Flt-1 may therefore be looked upon as a potential regulatory target at this stage of the disease. PMID:21408222

  6. Progressive outer retinal necrosis (PORN) in AIDS patients: a different appearance of varicella-zoster retinitis.

    Science.gov (United States)

    Pavesio, C E; Mitchell, S M; Barton, K; Schwartz, S D; Towler, H M; Lightman, S

    1995-01-01

    Retinal infections caused by the varicella-zoster virus (VZV) have been reported in immunocompetent and immunocompromised individuals. Two cases of a VZV-related retinitis are described with the characteristic features of the recently described progressive outer retinal necrosis (PORN) syndrome. Both patients suffered from the acquired immunodeficiency syndrome (AIDS) with greatly reduced peripheral blood CD4+ T lymphocyte counts, and presented with macular retinitis without vitritis. The disease was bilateral in one case and unilateral in the other. The clinical course was rapidly progressive with widespread retinal involvement and the development of rhegmatogenous retinal detachment with complete loss of vision in the affected eyes despite intensive intravenous antiviral therapy. VZV DNA was identified in vitreous biopsies, by molecular techniques based on the polymerase chain reaction (PCR), in both patients. At present, the use of very high-dose intravenous acyclovir may be the best therapeutic option in these patients for whom the visual prognosis is poor. Intravitreal antiviral drugs could also contribute to the management of these cases.

  7. Massive Bilateral Serous Retinal Detachment in a Case of Hypertensive Chorioretinopathy

    Directory of Open Access Journals (Sweden)

    Luis Villalba-Pinto

    2014-07-01

    Full Text Available Introduction: Systemic high blood pressure is related to a variety of retinal manifestations. We present an atypical case of hypertensive chorioretinopathy with massive bilateral serous retinal detachment. Case Report: A 26-year-old male with a genitourinary malformation and secondary grade IV chronic kidney failure as well as high blood pressure complained of acute vision loss. Dilated fundus examination evidenced a bilateral serous retinal detachment with macular involvement. The patient was unresponsive to oral antihypertensive therapy and dialysis treatment. The serous retinal detachment progressively decreased after the restoration of dialysis and antihypertensive therapy. The final visual acuity was 0.50 in both eyes. Discussion: In cases of serous macular detachment, it is mandatory to rule out different systemic and ocular diseases. The presence of uncontrolled high blood pressure may produce aggressive bilateral retinal changes, thus hypertension must be under early and strict control in order to improve the visual outcomes.

  8. Massive Bilateral Serous Retinal Detachment in a Case of Hypertensive Chorioretinopathy

    Science.gov (United States)

    Villalba-Pinto, Luis; Hernández-Ortega, M. Ángeles; de los Mozos, F. Javier Lavid; Pascual-Camps, Isabel; Dolz-Marco, Rosa; Arevalo, J. Fernando; Gallego-Pinazo, Roberto

    2014-01-01

    Introduction Systemic high blood pressure is related to a variety of retinal manifestations. We present an atypical case of hypertensive chorioretinopathy with massive bilateral serous retinal detachment. Case Report A 26-year-old male with a genitourinary malformation and secondary grade IV chronic kidney failure as well as high blood pressure complained of acute vision loss. Dilated fundus examination evidenced a bilateral serous retinal detachment with macular involvement. The patient was unresponsive to oral antihypertensive therapy and dialysis treatment. The serous retinal detachment progressively decreased after the restoration of dialysis and antihypertensive therapy. The final visual acuity was 0.50 in both eyes. Discussion In cases of serous macular detachment, it is mandatory to rule out different systemic and ocular diseases. The presence of uncontrolled high blood pressure may produce aggressive bilateral retinal changes, thus hypertension must be under early and strict control in order to improve the visual outcomes. PMID:25120474

  9. Personal identification based on blood vessels of retinal fundus images

    Science.gov (United States)

    Fukuta, Keisuke; Nakagawa, Toshiaki; Hayashi, Yoshinori; Hatanaka, Yuji; Hara, Takeshi; Fujita, Hiroshi

    2008-03-01

    Biometric technique has been implemented instead of conventional identification methods such as password in computer, automatic teller machine (ATM), and entrance and exit management system. We propose a personal identification (PI) system using color retinal fundus images which are unique to each individual. The proposed procedure for identification is based on comparison of an input fundus image with reference fundus images in the database. In the first step, registration between the input image and the reference image is performed. The step includes translational and rotational movement. The PI is based on the measure of similarity between blood vessel images generated from the input and reference images. The similarity measure is defined as the cross-correlation coefficient calculated from the pixel values. When the similarity is greater than a predetermined threshold, the input image is identified. This means both the input and the reference images are associated to the same person. Four hundred sixty-two fundus images including forty-one same-person's image pairs were used for the estimation of the proposed technique. The false rejection rate and the false acceptance rate were 9.9×10 -5% and 4.3×10 -5%, respectively. The results indicate that the proposed method has a higher performance than other biometrics except for DNA. To be used for practical application in the public, the device which can take retinal fundus images easily is needed. The proposed method is applied to not only the PI but also the system which warns about misfiling of fundus images in medical facilities.

  10. Optical Coherence Tomography Angiography of Retinal Cavernous Hemangioma.

    Science.gov (United States)

    Pierro, Luisa; Marchese, Alessandro; Gagliardi, Marco; Bandello, Francesco

    2017-08-01

    Retinal cavernous hemangioma is a rare, benign, retinal tumor characterized by angiomatous proliferation of vessels within the inner retina or the optic disc.1 Here we report a case of retinal cavernous hemangioma on the margin of the optic disc in the right eye of a 61-year-old asymptomatic female. The lesion was studied with multimodal imaging which included structural optical coherence tomography, fluorescein angiography, blue fundus auto-fluorescence, optical coherence tomography angiography (OCTA) (DRI OCT Triton; Topcon, Tokyo, Japan) and visual field examination. Blood circulation inside retinal cavernous hemangioma lesion is typically low-stagnant.2 However, OCTA demonstrated blood flow inside the lesion, illustrating its vascular circulation.3 Visual field was within the normal limits, except from a slight enlargement of the blind spot. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:684-685.]. Copyright 2017, SLACK Incorporated.

  11. Retinal detachment in paediatric patients

    International Nuclear Information System (INIS)

    Zafar, S. N.; Qureshi, N.; Azad, N.; Khan, A.

    2013-01-01

    Objective: To assess the causes of retinal detachment in children and the various operative procedures requiring vitreoretinal surgical intervention for the same. Study Design: Case series. Place and Duration of Study: Department of Ophthalmology, Al-Shifa Trust Eye Hospital, Rawalpindi, from January 2006 to May 2009. Methodology: A total of 281 eyes of 258 patients, (aged 0 - 18 years) who underwent vitreo-retinal surgical intervention for retinal detachment were included. Surgical log was searched for the type of retinal detachment and its causes. Frequencies of various interventions done in these patients viz. vitrectomy, scleral buckle, use of tamponading agents, laser photocoagulation and cryotherapy were noted. Results were described as descriptive statistics. Results: Myopia was the cause in 62 (22.1%) and trauma in 51 (18.1%) of the eyes. Total retinal detachment (RD) was treated in 94 (33.5%) eyes, sub total RD in 36 (12.8%), recurrent RD in 32 (11.4%), giant retinal tear in 28 (10%), tractional RD in 15 (5.3%) and exudative RD in 2 (0.7%). Prophylactic laser or cryotherapy was applied in 74 (26.3%) of the eyes. Pars plana vitrectomy (PPV) was carried out in 159 (56.6%) eyes while scleral buckle procedure was done in 129 (45.9%) eyes. Silicon oil was used in 149 (53%), perfluorocarbon liquid in 32 (11.4%) and gas tamponade in 20 (7.1%) eyes. Conclusion: The most common cause of retinal detachment in paediatric patients was myopia, followed by trauma. Total RD was more common as compared to the other types. The most common procedure adopted was pars plana vitrectomy followed by scleral buckle procedure. (author)

  12. Retinal phlebitis associated with autoimmune hemolytic anemia.

    Science.gov (United States)

    Chew, Fiona L M; Tajunisah, Iqbal

    2009-01-01

    To describe a case of retinal phlebitis associated with autoimmune hemolytic anemia. Observational case report. A 44-year-old Indian man diagnosed with autoimmune hemolytic anemia presented with a 1-week history of blurred vision in both eyes. Fundus biomicroscopy revealed bilateral peripheral retinal venous sheathing and cellophane maculopathy. Fundus fluorescent angiogram showed bilateral late leakage from the peripheral venous arcades and submacular fluid accumulation. The retinal phlebitis resolved following a blood transfusion and administration of systemic steroids. Retinopathy associated with autoimmune hemolytic anemia is not well known. This is thought to be the first documentation of retinal phlebitis occurring in this condition.

  13. Body fat distribution, metabolic and inflammatory markers and retinal microvasculature in school-age children. The Generation R Study.

    Science.gov (United States)

    Gishti, O; Jaddoe, V W V; Hofman, A; Wong, T Y; Ikram, M K; Gaillard, R

    2015-10-01

    To examine the associations of body fatness, metabolic and inflammatory markers with retinal vessel calibers among children. We performed a population-based cohort study among 4145 school-age children. At the median age of 6.0 years (95% range 5.8, 8.0 years), we measured body mass index, total and abdominal fat mass, metabolic and inflammatory markers (blood levels of lipids, insulin and C-peptide and C-reactive protein) and retinal vascular calibers from retinal photographs. We observed that compared with normal weight children, obese children had narrower retinal arteriolar caliber (difference -0.21 s.d. score (SDS; 95% confidence interval (CI) -0.35, -0.06)), but not venular caliber. Continuous analyses showed that higher body mass index and total body fat mass, but not android/gynoid fat mass ratio and pre-peritoneal fat mass, were associated with narrower retinal arteriolar caliber (Pfat mass), but not with retinal venular caliber. Lipid and insulin levels were not associated with retinal vessel calibers. Higher C-reactive protein was associated with only wider retinal venular caliber (difference 0.10 SDS (95% CI 0.06, 0.14) per SDS increase in C-reactive protein). This latter association was not influenced by body mass index. Higher body fatness is associated with narrower retinal arteriolar caliber, whereas increased C-reactive protein levels are associated with wider retinal venular caliber. Increased fat mass and inflammation correlate with microvascular development from school-age onwards.

  14. Blood-retinal barrier glycerol permeability in diabetic macular edema and healthy eyes: estimations from macular volume changes after peroral glycerol

    DEFF Research Database (Denmark)

    Thornit, Dorte Nellemann; Vinten, Carl Martin; Sander, Birgit

    2010-01-01

    PURPOSE: To compare the changes in macular volume (MV) between healthy subjects and patients with diabetic macular edema (DME) after an osmotic load and to determine the glycerol permeability (P(gly)) of the blood-retinal barrier (BRB). METHODS: In this unmasked study, 13 patients with DME and 5...

  15. Longitudinal changes of ocular blood flow using laser speckle flowgraphy during normal pregnancy.

    Directory of Open Access Journals (Sweden)

    Takahiro Sato

    Full Text Available Innovative laser speckle flowgraphy (LSFG enables noninvasive evaluation of retinal microcirculation and the usefulness has been reported in the field of ophthalmology. LSFG has allowed us to measure the real time changes of retinal blood flow without pupillary dilatations and contrast media. Herein, we investigated the change of retinal blood flow in normal pregnant women during gestation using LSFG.A prospective cohort study was conducted in 53 pregnant women who visited our institution between January, 2013 and July, 2014. Finally, a total of 41 participants without any obstetric complications were available for evaluation. Retinal blood flow was measured with LSFG in a total of 4 times during pregnancy (T1. 11-13 weeks, T2. 19-21 weeks, T3. 28-30 weeks, T4. 34-36 weeks and mean blur rate (MBR, blowout score (BOS, flow acceleration index (FAI, and resistive index (RI are analyzed from these measurements. Relations between LSFG parameters and mean arterial blood pressure (MAP are determined throughout pregnancy.MBR showed no significant changes throughout pregnancy. BOS showed a tendency to increase in the 3rd trimester. FAI values showed a slight increase from the 1st to 2nd trimester while a significant decrease was noted in the 3rd trimester. RI exhibited no changes between the 1st and 2nd trimesters, values decreased significantly after the 3rd trimester. MAP was positively correlated with BOS, and negatively correlated with FAI and RI.The present study clearly demonstrated that profiles of LSFG parameters demonstrated a decrease of resistance in retinal blood vessels. These changes in indices provide a highly sensitive reflection of physiological changes in vascular resistance due to pregnancy. Thus, LSFG may be useful, as a non-invasive, diagnostic tool to detect pregnancy related disorders such as preeclampsia.

  16. Retinal Thickening and Photoreceptor Loss in HIV Eyes without Retinitis.

    Directory of Open Access Journals (Sweden)

    Cheryl A Arcinue

    Full Text Available To determine the presence of structural changes in HIV retinae (i.e., photoreceptor density and retinal thickness in the macula compared with age-matched HIV-negative controls.Cohort of patients with known HIV under CART (combination Antiretroviral Therapy treatment were examined with a flood-illuminated retinal AO camera to assess the cone photoreceptor mosaic and spectral-domain optical coherence tomography (SD-OCT to assess retinal layers and retinal thickness.Twenty-four eyes of 12 patients (n = 6 HIV-positive and 6 HIV-negative were imaged with the adaptive optics camera. In each of the regions of interest studied (nasal, temporal, superior, inferior, the HIV group had significantly less mean cone photoreceptor density compared with age-matched controls (difference range, 4,308-6,872 cones/mm2. A different subset of forty eyes of 20 patients (n = 10 HIV-positive and 10 HIV-negative was included in the retinal thickness measurements and retinal layer segmentation with the SD-OCT. We observed significant thickening in HIV positive eyes in the total retinal thickness at the foveal center, and in each of the three horizontal B-scans (through the macular center, superior, and inferior to the fovea. We also noted that the inner retina (combined thickness from ILM through RNFL to GCL layer was also significantly thickened in all the different locations scanned compared with HIV-negative controls.Our present study shows that the cone photoreceptor density is significantly reduced in HIV retinae compared with age-matched controls. HIV retinae also have increased macular retinal thickness that may be caused by inner retinal edema secondary to retinovascular disease in HIV. The interaction of photoreceptors with the aging RPE, as well as possible low-grade ocular inflammation causing diffuse inner retinal edema, may be the key to the progressive vision changes in HIV-positive patients without overt retinitis.

  17. Nanomaterials and Retinal Toxicity

    Science.gov (United States)

    The neuroretina should be considered as a potential site of nanomaterial toxicity. Engineered nanomaterials may reach the retina through three potential routes of exposure including; intra­ vitreal injection of therapeutics; blood-borne delivery in the retinal vasculature an...

  18. Ethamsylate and blood loss in total hip replacement.

    Science.gov (United States)

    Keith, I

    1979-01-01

    Nineteen consecutive patients undergoing total hip replacement under epidural anaesthesia were randomly divided into two groups. The treatment group received 1000 mg of ethamsylate intravenously before induction of anaesthesia. Blood lost during surgery was measured by a colorimetric technique. Closed suction drains were used and all blood lost after operation collected for measurement. Ethamsylate did not decrease the average volumes of blood lost during or after the operation. Neither did it reduce the requirements for blood transfusion. Although there were no side-effects attributable to ethamyslate, there seems to be no indication for its use in total hip replacement under epidural anaesthesia.

  19. Do autologous blood transfusion systems reduce allogeneic blood transfusion in total knee arthroplasty?

    Science.gov (United States)

    Pawaskar, Aditya; Salunke, Abhijeet Ashok; Kekatpure, Aashay; Chen, Yongsheng; Nambi, G I; Tan, Junhao; Sonawane, Dhiraj; Pathak, Subodhkumar

    2017-09-01

    To study whether autologus blood transfusion systems reduce the requirement of allogneic blood transfusion in patients undergoing total knee arthroplasty. A comprehensive search of the published literature with PubMed, Scopus and Science direct database was performed. The following search terms were used: (total knee replacement) OR (total knee arthroplasty) OR (TKA) AND (blood transfusion) OR (autologous transfusion) OR (autologous transfusion system). Using search syntax, a total of 748 search results were obtained (79 from PubMed, 586 from Science direct and 83 from Scopus). Twenty-one randomized control trials were included for this meta-analysis. The allogenic transfusion rate in autologus blood transfusion (study) group was significantly lower than the control group (28.4 and 53.5 %, respectively) (p value 0.0001, Relative risk: 0.5). The median units of allogenic blood transfused in study control group and control group were 0.1 (0.1-3.0) and 1.3 (0.3-2.6), respectively. The median hospital stay in study group was 9 (6.7-15.6) days and control group was 8.7 (6.6-16.7) days. The median cost incurred for blood transfusion per patient in study and control groups was 175 (85.7-260) and 254.7 (235-300) euros, respectively. This meta-analysis demonstrates that the use of auto-transfusion systems is a cost-effective method to reduce the need for and quantity of allogenic transfusion in elective total knee arthroplasty. Level I.

  20. Perioperative blood saving measures in total hip and knee arthroplasty

    NARCIS (Netherlands)

    Horstmann, W.G.

    2011-01-01

    This dissertation explores and discusses different aspects of blood loss and blood-saving measures in total hip and knee arthroplasty. Background: Worldwide, approximately 1 million total hip and 1 million total knee prostheses are implanted each year. Total hip arthroplasty and total

  1. An automated retinal imaging method for the early diagnosis of diabetic retinopathy.

    Science.gov (United States)

    Franklin, S Wilfred; Rajan, S Edward

    2013-01-01

    Diabetic retinopathy is a microvascular complication of long-term diabetes and is the major cause for eyesight loss due to changes in blood vessels of the retina. Major vision loss due to diabetic retinopathy is highly preventable with regular screening and timely intervention at the earlier stages. Retinal blood vessel segmentation methods help to identify the successive stages of such sight threatening diseases like diabetes. To develop and test a novel retinal imaging method which segments the blood vessels automatically from retinal images, which helps the ophthalmologists in the diagnosis and follow-up of diabetic retinopathy. This method segments each image pixel as vessel or nonvessel, which in turn, used for automatic recognition of the vasculature in retinal images. Retinal blood vessels were identified by means of a multilayer perceptron neural network, for which the inputs were derived from the Gabor and moment invariants-based features. Back propagation algorithm, which provides an efficient technique to change the weights in a feed forward network, is utilized in our method. Quantitative results of sensitivity, specificity and predictive values were obtained in our method and the measured accuracy of our segmentation algorithm was 95.3%, which is better than that presented by state-of-the-art approaches. The evaluation procedure used and the demonstrated effectiveness of our automated retinal imaging method proves itself as the most powerful tool to diagnose diabetic retinopathy in the earlier stages.

  2. Unsupervised Retinal Vessel Segmentation Using Combined Filters.

    Directory of Open Access Journals (Sweden)

    Wendeson S Oliveira

    Full Text Available Image segmentation of retinal blood vessels is a process that can help to predict and diagnose cardiovascular related diseases, such as hypertension and diabetes, which are known to affect the retinal blood vessels' appearance. This work proposes an unsupervised method for the segmentation of retinal vessels images using a combined matched filter, Frangi's filter and Gabor Wavelet filter to enhance the images. The combination of these three filters in order to improve the segmentation is the main motivation of this work. We investigate two approaches to perform the filter combination: weighted mean and median ranking. Segmentation methods are tested after the vessel enhancement. Enhanced images with median ranking are segmented using a simple threshold criterion. Two segmentation procedures are applied when considering enhanced retinal images using the weighted mean approach. The first method is based on deformable models and the second uses fuzzy C-means for the image segmentation. The procedure is evaluated using two public image databases, Drive and Stare. The experimental results demonstrate that the proposed methods perform well for vessel segmentation in comparison with state-of-the-art methods.

  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. Carrier-Mediated Transport of Nicotine Across the Inner Blood-Retinal Barrier: Involvement of a Novel Organic Cation Transporter Driven by an Outward H(+) Gradient.

    Science.gov (United States)

    Tega, Yuma; Kubo, Yoshiyuki; Yuzurihara, Chihiro; Akanuma, Shin-Ichi; Hosoya, Ken-Ichi

    2015-09-01

    The present study was carried out to investigate the blood-to-retina transport of nicotine across the inner blood-retinal barrier (BRB). Using the in vivo vascular injection method, the blood-to-retina influx clearance of nicotine across the BRB was determined as 131 μL/(min?g retina), which is much higher than that of a nonpermeable paracellular marker, and blood-to-retina transport of nicotine was inhibited by organic cations such as pyrilamine and verapamil. The nicotine uptake by a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB2 cells), an in vitro model of the inner BRB, exhibited time, temperature, and concentration dependence with a Km of 492 μM. These results suggest the involvement of a carrier-mediated transport process in nicotine transport in the inner BRB. The nicotine uptake by TR-iBRB2 cells was stimulated by an outwardly directed H(+) gradient, and the uptake was significantly inhibited by bulky and hydrophobic cationic drugs, whereas inhibitors of organic cation transporters did not show inhibitory effect. These results suggest that the novel organic cation transport system driven by an outwardly directed H(+) gradient is involved in the blood-to-retina transport of nicotine across the inner BRB. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  5. Inner Retinal Oxygen Delivery, Metabolism, and Extraction Fraction in Ins2Akita Diabetic Mice.

    Science.gov (United States)

    Blair, Norman P; Wanek, Justin; Felder, Anthony E; Brewer, Katherine C; Joslin, Charlotte E; Shahidi, Mahnaz

    2016-11-01

    Retinal nonperfusion and hypoxia are important factors in human diabetic retinopathy, and these presumably inhibit energy production and lead to cell death. The purpose of this study was to elucidate the effect of diabetes on inner retinal oxygen delivery and metabolism in a mouse model of diabetes. Phosphorescence lifetime and blood flow imaging were performed in spontaneously diabetic Ins2Akita (n = 22) and nondiabetic (n = 22) mice at 12 and 24 weeks of age to measure retinal arterial (O2A) and venous (O2V) oxygen contents and total retinal blood flow (F). Inner retinal oxygen delivery (DO2) and metabolism (MO2) were calculated as F ∗ O2A and F ∗ (O2A - O2V), respectively. Oxygen extraction fraction (OEF), which equals MO2/DO2, was calculated. DO2 at 12 weeks were 112 ± 40 and 97 ± 29 nL O2/min in nondiabetic and diabetic mice, respectively (NS), and 148 ± 31 and 85 ± 37 nL O2/min at 24 weeks, respectively (P < 0.001). MO2 were 65 ± 31 and 66 ± 27 nL O2/min in nondiabetic and diabetic mice at 12 weeks, respectively, and 79 ± 14 and 54 ± 28 nL O2/min at 24 weeks, respectively (main effects = NS). At 12 weeks OEF were 0.57 ± 0.17 and 0.67 ± 0.09 in nondiabetic and diabetic mice, respectively, and 0.54 ± 0.07 and 0.63 ± 0.08 at 24 weeks, respectively (main effect of diabetes: P < 0.01). Inner retinal MO2 was maintained in diabetic Akita mice indicating that elevation of the OEF adequately compensated for reduced DO2 and prevented oxidative metabolism from being limited by hypoxia.

  6. Noninvasive Imaging of Retinal Morphology and Microvasculature in Obese Mice Using Optical Coherence Tomography and Optical Microangiography

    Science.gov (United States)

    Zhi, Zhongwei; Chao, Jennifer R.; Wietecha, Tomasz; Hudkins, Kelly L.; Alpers, Charles E.; Wang, Ruikang K.

    2014-01-01

    Purpose. To evaluate early diabetes-induced changes in retinal thickness and microvasculature in a type 2 diabetic mouse model by using optical coherence tomography (OCT)/optical microangiography (OMAG). Methods. Twenty-two-week-old obese (OB) BTBR mice (n = 10) and wild-type (WT) control mice (n = 10) were imaged. Three-dimensional (3D) data volumes were captured with spectral domain OCT using an ultrahigh-sensitive OMAG scanning protocol for 3D volumetric angiography of the retina and dense A-scan protocol for measurement of the total retinal blood flow (RBF) rate. The thicknesses of the nerve fiber layer (NFL) and that of the NFL to the inner plexiform layer (IPL) were measured and compared between OB and WT mice. The linear capillary densities within intermediate and deep capillary layers were determined by the number of capillaries crossing a 500-μm line. The RBF rate was evaluated using an en face Doppler approach. These quantitative measurements were compared between OB and WT mice. Results. The retinal thickness of the NFL to IPL was significantly reduced in OB mice (P < 0.01) compared to that in WT mice, whereas the NFL thickness between the two was unchanged. 3D depth-resolved OMAG angiography revealed the first in vivo 3D model of mouse retinal microcirculation. Although no obvious differences in capillary vessel densities of the intermediate and deep capillary layers were detected between normal and OB mice, the total RBF rate was significantly lower (P < 0.05) in OB mice than in WT mice. Conclusions. We conclude that OB BTBR mice have significantly reduced NFL–IPL thicknesses and total RBF rates compared with those of WT mice, as imaged by OCT/OMAG. OMAG provides an unprecedented capability for high-resolution depth-resolved imaging of mouse retinal vessels and blood flow that may play a pivotal role in providing a noninvasive method for detecting early microvascular changes in patients with diabetic retinopathy. PMID:24458155

  7. Original Article Blood Loss and Influencing Factors in Primary Total ...

    African Journals Online (AJOL)

    KIGZ

    aid the surgeon in the African region estimate the expected blood loss after total hip replacement. We conducted a study to quantify the blood loss following total hip arthroplasty and to determine the factors .... Hemoglobin European Overview (OSTHEO) study: blood management in elective knee and hip arthroplasty in ...

  8. 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.

  9. Mitochondrial transcription factor A (Tfam) gene sequencing and mitochondrial evaluation in inherited retinal dysplasia in miniature schnauzer dogs.

    Science.gov (United States)

    Bauer, Bianca S; Forsyth, George W; Sandmeyer, Lynne S; Grahn, Bruce H

    2011-04-01

    Mitochondrial transcription factor A (Tfam) has been implicated in the pathogenesis of retinal dysplasia in miniature schnauzer dogs and it has been proposed that affected dogs have altered mitochondrial numbers, size, and morphology. To test these hypotheses the Tfam gene of affected and normal miniature schnauzer dogs with retinal dysplasia was sequenced and lymphocyte mitochondria were quantified, measured, and the morphology was compared in normal and affected dogs using transmission electron microscopy. For Tfam sequencing, retina, retinal pigment epithelium (RPE), and whole blood samples were collected. Total RNA was isolated from the retina and RPE and reverse transcribed to make cDNA. Genomic DNA was extracted from white blood cell pellets obtained from the whole blood samples. The Tfam coding sequence, 5' promoter region, intron1 and the 3' non-coding sequence of normal and affected dogs were amplified using polymerase chain reaction (PCR), cloned and sequenced. For electron microscopy, lymphocytes from affected and normal dogs were photographed and the mitochondria within each cross-section were identified, quantified, and the mitochondrial area (μm²) per lymphocyte cross-section was calculated. Lastly, using a masked technique, mitochondrial morphology was compared between the 2 groups. Sequencing of the miniature schnauzer Tfam gene revealed no functional sequence variation between affected and normal dogs. Lymphocyte and mitochondrial area, mitochondrial quantification, and morphology assessment also revealed no significant difference between the 2 groups. Further investigation into other candidate genes or factors causing retinal dysplasia in the miniature schnauzer is warranted.

  10. Total and antigen-specific Ige levels in umbilical cord blood

    Directory of Open Access Journals (Sweden)

    Sybilski AJ

    2009-12-01

    Full Text Available Abstract The present study was conducted to learn whether the perinatal and environmental factors could influence the total and antigen-specific IgE levels in umbilical cord blood. Retrospective data were obtained from 173 mother-infant pairs. Total and specific (for children's food, wheat/grass and house dust mite-HDM cord blood IgE levels were determined using the immunoassay test. The total cord blood IgE was between 0.0-23.08 IU/ml (mean 0.55 ± 2.07 IU/ml; median 0.16 IU/ml. Total IgE levels were significantly higher in boys compared with girls (OR = 2.2; P = 0.007, and in newborns with complicated pregnancy (OR = 2.7; P = 0.003. A greater number of siblings correlated with increases in the total cord blood IgE (P

  11. Association of parental blood pressure with retinal microcirculatory abnormalities indicative of endothelial dysfunction in children.

    Science.gov (United States)

    Islam, Muhammad; Jafar, Tazeen H; Bux, Rasool; Hashmi, Shiraz; Chaturvedi, Nish; Hughes, Alun D

    2014-03-01

    Microcirculatory abnormalities precede the onset of hypertension and may explain its familial nature. We examined the relationship between parental blood pressure (BP) and offspring retinal microvasculature in Pakistani trios [father, mother, and child (aged 9-14 years)]. This is a substudy of a population-based trial of BP reduction. Data were available on 358 normotensive, and 410 offspring of at least one hypertensive parent. Retinal vessel characteristics were measured from digital images. Multivariable linear regression models were built to assess the associations between maternal and paternal BP and offspring retinal microvasculature. Optimality deviation was greatest in offspring of two hypertensive parents, compared with those with one or no hypertensive parent (P=0.030 for trend). Paternal SBP and DBP were each significantly associated with optimality deviation in offspring (P=0.023 and P=0.006, respectively). This relationship persisted after accounting for offspring cardiovascular risk factors [increase in optimality deviation (95% confidence interval, CI) 0.0053 (0.0001-0.0106, P=0.047) and 0.0109 (0.0025-0.0193, P=0.011), for each 10 mmHg increase in paternal SBP and DBP, respectively]. Maternal DBP was inversely associated with offspring arteriovenous ratio -0.0102 (-0.0198 to -0.0007, P=0.035). Microvascular endothelial dysfunction in children is associated with increasing levels of parental hypertension. The association with paternal BP is independent of other cardiovascular risk factors, including the child's BP. Higher maternal DBP is associated with evidence of arteriolar narrowing in offspring. These early microcirculatory changes may help explain familial predisposition to hypertension in people of Pakistani origin at an early age. :

  12. Impaired increase of retinal capillary blood flow to flicker light exposure in arterial hypertension.

    Science.gov (United States)

    Ritt, Martin; Harazny, Joanna M; Ott, Christian; Raff, Ulrike; Bauernschubert, Philipp; Lehmann, Marina; Michelson, Georg; Schmieder, Roland E

    2012-09-01

    We hypothesized that the increase of retinal capillary blood flow (RCF) to flicker light exposure is impaired in subjects with arterial hypertension. In 146 nondiabetic untreated male subjects with (n=50) or without (n=96) arterial hypertension, RCF was measured before and after flicker light exposure noninvasively and in vivo using scanning laser Doppler flowmetry. In addition, in a subgroup of 28 subjects, the change of RCF to flicker light exposure was again assessed during parallel infusion of nitric oxide synthase inhibitor N-monomethyl-L-arginine (L-NMMA). The increase of RCF to flicker light exposure was lower in patients with untreated hypertension compared with normotensive subjects when expressed in absolute terms (7.69±54 versus 27.2±44 AU; P adjusted=0.013) or percent changes (2.95±14 versus 8.33±12%; P adjusted=0.023). Systolic (β=-0.216; P=0.023) but not diastolic blood pressure (β=-0.117; P=0.243) or mean arterial pressure (β=-0.178; P=0.073) was negatively related to the percent change of RCF to flicker light exposure, independently of other cardiovascular risk factors. In the subgroup of 28 subjects, the increase of RCF to flicker light exposure was similar at baseline and during parallel infusion of L-NMMA when expressed in absolute terms (20.0±51 versus 22.6±56 AU; P=0.731) or percent changes (7.12±16 versus 8.29±18%; P=0.607). The increase of RCF to flicker light exposure is impaired in arterial hypertension. In the subgroup of the total study cohort, nitric oxide was not a major determinant of the increase of RCF to flicker light exposure.

  13. Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future

    Directory of Open Access Journals (Sweden)

    Mingyue Luo

    2018-01-01

    Full Text Available As a constituent of blood-retinal barrier and retinal outer segment (ROS scavenger, retinal pigmented epithelium (RPE is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

  14. Application of stem cell-derived retinal pigmented epithelium in retinal degenerative diseases: present and future.

    Science.gov (United States)

    Luo, Mingyue; Chen, Youxin

    2018-01-01

    As a constituent of blood-retinal barrier and retinal outer segment (ROS) scavenger, retinal pigmented epithelium (RPE) is fundamental to normal function of retina. Malfunctioning of RPE contributes to the onset and advance of retinal degenerative diseases. Up to date, RPE replacement therapy is the only possible method to completely reverse retinal degeneration. Transplantation of human RPE stem cell-derived RPE (hRPESC-RPE) has shown some good results in animal models. With promising results in terms of safety and visual improvement, human embryonic stem cell-derived RPE (hESC-RPE) can be expected in clinical settings in the near future. Despite twists and turns, induced pluripotent stem cell-derived RPE (iPSC-RPE) is now being intensely investigated to overcome genetic and epigenetic instability. By far, only one patient has received iPSC-RPE transplant, which is a hallmark of iPSC technology development. During follow-up, no major complications such as immunogenicity or tumorigenesis have been observed. Future trials should keep focusing on the safety of stem cell-derived RPE (SC-RPE) especially in long period, and better understanding of the nature of stem cell and the molecular events in the process to generate SC-RPE is necessary to the prosperity of SC-RPE clinical application.

  15. Determination of retinal surface area.

    Science.gov (United States)

    Nagra, Manbir; Gilmartin, Bernard; Thai, Ngoc Jade; Logan, Nicola S

    2017-09-01

    Previous attempts at determining retinal surface area and surface area of the whole eye have been based upon mathematical calculations derived from retinal photographs, schematic eyes and retinal biopsies of donor eyes. 3-dimensional (3-D) ocular magnetic resonance imaging (MRI) allows a more direct measurement, it can be used to image the eye in vivo, and there is no risk of tissue shrinkage. The primary purpose of this study is to compare, using T2-weighted 3D MRI, retinal surface areas for superior-temporal (ST), inferior-temporal (IT), superior-nasal (SN) and inferior-nasal (IN) retinal quadrants. An ancillary aim is to examine whether inter-quadrant variations in area are concordant with reported inter-quadrant patterns of susceptibility to retinal breaks associated with posterior vitreous detachment (PVD). Seventy-three adult participants presenting without retinal pathology (mean age 26.25 ± 6.06 years) were scanned using a Siemens 3-Tesla MRI scanner to provide T2-weighted MR images that demarcate fluid-filled internal structures for the whole eye and provide high-contrast delineation of the vitreous-retina interface. Integrated MRI software generated total internal ocular surface area (TSA). The second nodal point was used to demarcate the origin of the peripheral retina in order to calculate total retinal surface area (RSA) and quadrant retinal surface areas (QRSA) for ST, IT, SN, and IN quadrants. Mean spherical error (MSE) was -2.50 ± 4.03D and mean axial length (AL) 24.51 ± 1.57 mm. Mean TSA and RSA for the RE were 2058 ± 189 and 1363 ± 160 mm 2 , respectively. Repeated measures anova for QRSA data indicated a significant difference within-quadrants (P area/mm increase in AL. Although the differences between QRSAs are relatively small, there was evidence of concordance with reported inter-quadrant patterns of susceptibility to retinal breaks associated with PVD. The data allow AL to be converted to QRSAs, which will assist further

  16. Retinal blood vessel segmentation in high resolution fundus photographs using automated feature parameter estimation

    Science.gov (United States)

    Orlando, José Ignacio; Fracchia, Marcos; del Río, Valeria; del Fresno, Mariana

    2017-11-01

    Several ophthalmological and systemic diseases are manifested through pathological changes in the properties and the distribution of the retinal blood vessels. The characterization of such alterations requires the segmentation of the vasculature, which is a tedious and time-consuming task that is infeasible to be performed manually. Numerous attempts have been made to propose automated methods for segmenting the retinal vasculature from fundus photographs, although their application in real clinical scenarios is usually limited by their ability to deal with images taken at different resolutions. This is likely due to the large number of parameters that have to be properly calibrated according to each image scale. In this paper we propose to apply a novel strategy for automated feature parameter estimation, combined with a vessel segmentation method based on fully connected conditional random fields. The estimation model is learned by linear regression from structural properties of the images and known optimal configurations, that were previously obtained for low resolution data sets. Our experiments in high resolution images show that this approach is able to estimate appropriate configurations that are suitable for performing the segmentation task without requiring to re-engineer parameters. Furthermore, our combined approach reported state of the art performance on the benchmark data set HRF, as measured in terms of the F1-score and the Matthews correlation coefficient.

  17. [Static Retinal Vessel Analysis in Population-based Study SHIP-Trend].

    Science.gov (United States)

    Theophil, Constanze; Jürgens, Clemens; Großjohann, Rico; Kempin, Robert; Ittermann, Till; Nauck, Matthias; Völzke, Henry; Tost, Frank H W

    2017-08-24

    Background Interdisciplinary investigations of possible connections between general diseases and ophthalmological changes are difficult to perform in the clinical environment. But they are gaining in importance as a result of the age-related increase in chronic diseases. The collection of health-related parameters in the Study of Health in Pomerania (SHIP) project allows to derive conclusions for the general population. Methods The population-based SHIP trend study was conducted between 2008 and 2012 in Greifswald. The baseline cohort included 4420 subjects (response 50.1%) at the age of 20 to 84 years. The pre-existence of arterial hypertension, diabetes mellitus and smoking status were questioned in a standardized questionnaire, the blood pressure and the HbA 1c were determined by the laboratory. The vascular diameter of retinal arterioles and venules were determined by means of non-mydriatic fundus images and the retinal arterial (CRAE) and venous equivalent (CRVE) were calculated therefrom. The association of diabetes mellitus, HbA 1c , smoking status and blood pressure with the retinal vascular parameters was tested for age and sex with linear regression models. Results In 3218 subjects with evaluable standardized fundus photographs, significant associations of elevated HbA 1c (> 6.5%), smoking status and systolic and diastolic blood pressure were found with the retinal vessel widths CRAE and CRVE. Anamnestic diabetes mellitus, on the other hand, was not associated with any of the vascular parameters. Conclusion This research study reveals a relevant correlation between general diseases and the retinal blood flow in the eye. Therefore, general diseases can induce ophthalmological changes and eye examination can provide information for the assessment of general diseases. Georg Thieme Verlag KG Stuttgart · New York.

  18. Spontaneous high frequency diameter oscillations of larger retinal arterioles are reduced in type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Bek, Toke; Jeppesen, Peter; Kanters, Jørgen K.

    2013-01-01

    Diabetic retinopathy is characterized by morphological changes in the retina secondary to disturbances in retinal blood flow. Vasomotion is a mechanism for regulating blood flow by spontaneous oscillations in the diameter of retinal resistance arterioles, and has been shown to be disturbed outside...... the eye in diabetic patients. Therefore, the purpose of the present study was to characterize spontaneous oscillations in the diameter of retinal arterioles in normal persons and in persons with different severity of diabetic retinopathy....

  19. Total retinal detachment occurring after minor head trauma.

    Science.gov (United States)

    Mircea, Pienaru; Ramona, Serban; Mircea, Filip; Andrei, Filip

    2015-01-01

    The objective of this article is to present the case of a patient with a severe decrease of visual acuity that occurred after an apparently minor head injury. Following the investigations, the patient was diagnosed with rhegmatogenous retinal detachment that was triggered by a fall from the same level and which occurred on a background of lattice degeneration. In this case, a minor trauma caused a severe complication because the patient had a contributing factor for the complication. The patient was operated and the end result was satisfactory.

  20. Retinal detachment and retinal holes in retinitis pigmentosa sine pigmento.

    Science.gov (United States)

    Csaky, K; Olk, R J; Mahl, C F; Bloom, S M

    1991-01-01

    Retinal detachment and retinal holes in two family members with retinitis pigmentosa sine pigmento are reported. We believe these are the first such cases reported in the literature. We describe the presenting symptoms and management, including cryotherapy, scleral buckling procedure, and sulfur hexafluoride injection (SF6), resulting in stable visual acuity in one case and retinal reattachment and improved visual acuity in the other case.

  1. Hypertensive retinopathy identification through retinal fundus image using backpropagation neural network

    Science.gov (United States)

    Syahputra, M. F.; Amalia, C.; Rahmat, R. F.; Abdullah, D.; Napitupulu, D.; Setiawan, M. I.; Albra, W.; Nurdin; Andayani, U.

    2018-03-01

    Hypertension or high blood pressure can cause damage of blood vessels in the retina of eye called hypertensive retinopathy (HR). In the event Hypertension, it will cause swelling blood vessels and a decrese in retina performance. To detect HR in patients body, it is usually performed through physical examination of opthalmoscope which is still conducted manually by an ophthalmologist. Certainly, in such a manual manner, takes a ong time for a doctor to detetct HR on aa patient based on retina fundus iamge. To overcome ths problem, a method is needed to identify the image of retinal fundus automatically. In this research, backpropagation neural network was used as a method for retinal fundus identification. The steps performed prior to identification were pre-processing (green channel, contrast limited adapative histogram qualization (CLAHE), morphological close, background exclusion, thresholding and connected component analysis), feature extraction using zoning. The results show that the proposed method is able to identify retinal fundus with an accuracy of 95% with maximum epoch of 1500.

  2. Long-Term Outcomes of Total Exudative Retinal Detachments in Stage 3B Coats Disease.

    Science.gov (United States)

    Li, Albert S; Capone, Antonio; Trese, Michael T; Sears, Jonathan E; Kychenthal, Andres; De la Huerta, Irina; Ferrone, Philip J

    2018-06-01

    To evaluate the long-term outcomes of treatment of total exudative retinal detachments (ERDs) secondary to Coats disease (stage 3B) and the role of vitrectomy. Retrospective, observational case series. A total of 16 eyes in 16 patients undergoing treatment for total ERDs secondary to Coats disease with at least 5 years of follow-up. We reviewed the records of patients with stage 3B Coats disease. The interventions, including the timing of vitrectomy if used, and clinical course were recorded. The primary outcome measures were visual acuity at the most recent appointment, whether there was progression to neovascular glaucoma (NVG) or phthisis bulbi, and need for enucleation. All patients received ablative treatment (photocoagulation or cryotherapy), with 8 having scleral buckling (SB) and 6 having external drainage of subretinal fluid (XD). Of the 12 patients who had pars plana vitrectomy (PPV), 8 had early PPV (EV) in the first year after presenting, and 4 of 8 in the expectant management group had late PPV (late vitrectomy) at a mean of 4.3 years post-presentation for treatment of significant traction retinal detachment (TRD). The other 4 patients of 8 in the expectant management group did not require vitrectomy. Mean follow-up overall was 9 1/2 years. At the date of last follow-up, 50% had no light perception or light perception vision, which was consistent across the subgroups that underwent EV (4/8), late vitrectomy (2/4), or no PPV (2/4). A total of 4 of 16 patients had progression to NVG or phthisis, 1 of whom required enucleation. In this retrospective series of patients with Stage 3B Coats disease, ablative therapy with a combination of PPV, XD, or SB was effective in preventing progression to NVG or phthisis in the majority of patients, thus preserving the globe. Half of the patients (4/8) in this series who did not undergo PPV in the early vitrectomy group developed late-onset TRD, suggesting a possible role for early prophylactic vitrectomy with possible

  3. Blood Conservation Strategies in Total Hip and Knee Arthroplasty

    Directory of Open Access Journals (Sweden)

    David Liu

    2015-01-01

    Full Text Available Peri-operative blood management is one of a number of components important for successful patient care in total joint arthroplasty and surgeons should be proactive in its application. The aims of blood conservation are to reduce the risks of blood transfusion whilst at the same time maximizing haemaglobin in the post-operative period, thereby leading to a positive effect on early and long term outcomes and costs. An individualized strategy based on patient specific risk factors, anticipated blood loss and co-morbidities is useful in achieving this aim. Multiple blood conservation strategies are available in the pre-operative, intra-operative and post-operative periods and can be utilised either individually or in combination. Recent literature has highlighted the importance of identifying and correcting pre-operative anaemia, salvaging peri-operative red cells and the use of tranexamic acid in reducing blood loss. Given total hip and knee arthroplasty is an elective procedure, a zero allogenic blood transfusion rate should be the aim and an achievable goal.

  4. Impaired Retinal Vasodilator Responses in Prediabetes and Type 2 Diabetes

    Science.gov (United States)

    Lott, Mary E.J.; Slocomb, Julia E.; Shivkumar, Vikram; Smith, Bruce; Quillen, David; Gabbay, Robert A.; Gardner, Thomas W.; Bettermann, Kerstin

    2013-01-01

    Purpose In diabetes, endothelial dysfunction and subsequent structural damage to blood vessels can lead to heart attacks, retinopathy and strokes. However, it is unclear whether prediabetic subjects exhibit microvascular dysfunction indicating early stages of arteriosclerosis and vascular risk. The purpose of this study was to examine whether retinal reactivity may be impaired early in the hyperglycemic continuum and may be associated with markers of inflammation. Methods Individuals with prediabetes (n = 22), type 2 diabetes (n = 25) and healthy age and body composition matched controls (n = 19) were studied. We used the Dynamic Vessel Analyzer to assess retinal vasoreactivity (percent change in vessel diameter) during a flickering light stimulation. Fasting highly sensitive c-reactive protein (hs-CRP), a marker of inflammation, was measured in blood plasma. Results Prediabetic and diabetic individuals had attenuated peak vasodilator and relative amplitude changes in retinal vein diameters to the flickering light stimulus compared to healthy controls (peak dilation: prediabetic subjects 3.3 ± 1.8 %, diabetic subjects 3.3 ± 2.1% controls 5.6 ± 2.6%, p = .001; relative amplitude: prediabetic subjects 4.3 ± 2.2%, diabetic subjects 5.0 ± 2.6% and control subjects 7.2 ± 3.2%, p = .003). Similar findings were observed in retinal arteries. Levels of hs-CRP were not associated with either retinal vessel response parameters. Conclusion Retinal reactivity was impaired in prediabetic and type 2 diabetic individuals in parallel with reduced insulin sensitivity but not associated with levels of hs-CRP. Retinal vasoreactivity measurements may be a sensitive tool to assess early vascular risk. PMID:23742315

  5. Registration of retinal sequences from new video-ophthalmoscopic camera.

    Science.gov (United States)

    Kolar, Radim; Tornow, Ralf P; Odstrcilik, Jan; Liberdova, Ivana

    2016-05-20

    Analysis of fast temporal changes on retinas has become an important part of diagnostic video-ophthalmology. It enables investigation of the hemodynamic processes in retinal tissue, e.g. blood-vessel diameter changes as a result of blood-pressure variation, spontaneous venous pulsation influenced by intracranial-intraocular pressure difference, blood-volume changes as a result of changes in light reflection from retinal tissue, and blood flow using laser speckle contrast imaging. For such applications, image registration of the recorded sequence must be performed. Here we use a new non-mydriatic video-ophthalmoscope for simple and fast acquisition of low SNR retinal sequences. We introduce a novel, two-step approach for fast image registration. The phase correlation in the first stage removes large eye movements. Lucas-Kanade tracking in the second stage removes small eye movements. We propose robust adaptive selection of the tracking points, which is the most important part of tracking-based approaches. We also describe a method for quantitative evaluation of the registration results, based on vascular tree intensity profiles. The achieved registration error evaluated on 23 sequences (5840 frames) is 0.78 ± 0.67 pixels inside the optic disc and 1.39 ± 0.63 pixels outside the optic disc. We compared the results with the commonly used approaches based on Lucas-Kanade tracking and scale-invariant feature transform, which achieved worse results. The proposed method can efficiently correct particular frames of retinal sequences for shift and rotation. The registration results for each frame (shift in X and Y direction and eye rotation) can also be used for eye-movement evaluation during single-spot fixation tasks.

  6. Exploring the relationship of peripheral total bilirubin, red blood cell, and hemoglobin with blood pressure during childhood and adolescence.

    Science.gov (United States)

    Chen, Xiao-Tian; Yang, Song; Yang, Ya-Ming; Zhao, Hai-Long; Chen, Yan-Chun; Zhao, Xiang-Hai; Wen, Jin-Bo; Tian, Yuan-Rui; Yan, Wei-Li; Shen, Chong

    2017-11-04

    Total bilirubin is beneficial for protecting cardiovascular diseases in adults. The authors aimed to investigate the association of total bilirubin, red blood cell, and hemoglobin levels with the prevalence of high blood pressure in children and adolescents. A total of 3776 students (aged from 6 to 16 years old) were examined using cluster sampling. Pre-high blood pressure and high blood pressure were respectively defined as the point of 90th and 95th percentiles based on the Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents. Both systolic and diastolic blood pressure were standardized into z-scores. Peripheral total bilirubin, red blood cell and hemoglobin levels were significantly correlated with age, and also varied with gender. Peripheral total bilirubin was negatively correlated with systolic blood pressure in 6- and 9-year-old boys, whilst positively correlated with diastolic blood pressure in the 12-year-old boys and 13- to 15-year-old girls (p0.05). Total bilirubin could be weakly correlated with both systolic and diastolic blood pressure, as correlations varied with age and gender in children and adolescents; in turn, the increased levels of red blood cell and hemoglobin are proposed to be positively associated with the prevalence of high blood pressure. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  7. Prophylactic treatment of retinal breaks

    DEFF Research Database (Denmark)

    Blindbæk, Søren Leer; Grauslund, Jakob

    2015-01-01

    Prophylactic treatment of retinal breaks has been examined in several studies and reviews, but so far, no studies have successfully applied a systematic approach. In the present systematic review, we examined the need of follow-up after posterior vitreous detachment (PVD) - diagnosed by slit...... published before 2012. Four levels of screening identified 13 studies suitable for inclusion in this systematic review. No meta-analysis was conducted as no data suitable for statistical analysis were identified. In total, the initial examination after symptomatic PVD identified 85-95% of subsequent retinal......-47% of cases, respectively. The cumulated incidence of RRD despite prophylactic treatment was 2.1-8.8%. The findings in this review suggest that follow-up after symptomatic PVD is only necessary in cases of incomplete retinal examination at presentation. Prophylactic treatment of symptomatic retinal breaks...

  8. Platform image processing to study the structural properties of retinal vessel

    Directory of Open Access Journals (Sweden)

    Miguel Ángel MERCHÁN

    2013-05-01

    Full Text Available This paper presents a technological platform specialized in assessing retinal vessel caliber and describing the relationship of the results obtained to cardiovascular risk. Retinal circulation is an area of active research by numerous groups, and there is general experimental agreement on the analysis of the patterns of the retinal blood vessels in the normal human retina. The development of automated tools designed to improve performance and decrease interobserver variability, therefore, appears necessary. 

  9. 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.

  10. Missed retinal breaks in rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    Brijesh Takkar

    2016-12-01

    Full Text Available AIM: To evaluate the causes and associations of missed retinal breaks (MRBs and posterior vitreous detachment (PVD in patients with rhegmatogenous retinal detachment (RRD. METHODS: Case sheets of patients undergoing vitreo retinal surgery for RRD at a tertiary eye care centre were evaluated retrospectively. Out of the 378 records screened, 253 were included for analysis of MRBs and 191 patients were included for analysis of PVD, depending on the inclusion criteria. Features of RRD and retinal breaks noted on examination were compared to the status of MRBs and PVD detected during surgery for possible associations. RESULTS: Overall, 27% patients had MRBs. Retinal holes were commonly missed in patients with lattice degeneration while missed retinal tears were associated with presence of complete PVD. Patients operated for cataract surgery were significantly associated with MRBs (P=0.033 with the odds of missing a retinal break being 1.91 as compared to patients with natural lens. Advanced proliferative vitreo retinopathy (PVR and retinal bullae were the most common reasons for missing a retinal break during examination. PVD was present in 52% of the cases and was wrongly assessed in 16%. Retinal bullae, pseudophakia/aphakia, myopia, and horse shoe retinal tears were strongly associated with presence of PVD. Traumatic RRDs were rarely associated with PVD. CONCLUSION: Pseudophakic patients, and patients with retinal bullae or advanced PVR should be carefully screened for MRBs. Though Weiss ring is a good indicator of PVD, it may still be over diagnosed in some cases. PVD is associated with retinal bullae and pseudophakia, and inversely with traumatic RRD.

  11. Total hepatofugal portal blood flow in cirrhosis demonstrated by transhepatic portography

    Energy Technology Data Exchange (ETDEWEB)

    Burcharth, F; Aagaard, J

    1988-01-01

    We investigated 108 patients with cirrhosis of the liver and portal hypertension by percutaneous transhepatic portography to demonstrate the occurrence and frequency of total hepatofugal portal blood flow. Sixteen patients (14.8%) had a total hepatofugal portal blood flow. The aetiology of portal hypertension and the portal pressure did not differ from that in the group of patients with hepatopetal portal blood flow. A significantly higher percentage of patients in the group with hepatofugal flow had gastro-oesophageal varices (P < 0.025). All patients with varices had bled. Half of the patients in the group with hepatofugal blood flow had a false splenoportographic diagnosis of portal vein thrombosis. In conclusion, total hepatofugal postal blood flow exists more often than hitherto assumed. Hepatofugal blood flow does not relieve portal hypertension nor prevent development of gastro-oesophageal varices or bleeding.

  12. Retinal vessel diameter and estimated cerebrospinal fluid pressure in arterial hypertension: the Beijing Eye Study.

    Science.gov (United States)

    Jonas, Jost B; Wang, Ningli; Wang, Shuang; Wang, Ya Xing; You, Qi Sheng; Yang, Diya; Wei, Wen Bin; Xu, Liang

    2014-09-01

    Hypertensive retinal microvascular abnormalities include an increased retinal vein-to-artery diameter ratio. Because central retinal vein pressure depends on cerebrospinal fluid pressure (CSFP), we examined whether the retinal vein-to-artery diameter ratio and other retinal hypertensive signs are associated with CSFP. Participants of the population-based Beijing Eye Study (n = 1,574 subjects) underwent measurement of the temporal inferior and superior retinal artery and vein diameter. CSFP was calculated as 0.44 × body mass index (kg/m(2)) + 0.16 × diastolic blood pressure (mm Hg) - 0.18 × age (years) - 1.91. Larger retinal vein diameters and higher vein-to-artery diameter ratios were significantly associated with higher estimated CSFP (P = 0.001) in multivariable analysis. In contrast, temporal inferior retinal arterial diameter was marginally associated (P = 0.03) with estimated CSFP, and temporal superior artery diameter was not significantly associated (P = 0.10) with estimated CSFP; other microvascular abnormalities, such as arteriovenous crossing signs, were also not significantly associated with estimated CSFP. In a reverse manner, higher estimated CSFP as a dependent variable in the multivariable analysis was associated with wider retinal veins and higher vein-to-artery diameter ratio. In the same model, estimated CSFP was not significantly correlated with retinal artery diameters or other retinal microvascular abnormalities. Correspondingly, arterial hypertension was associated with retinal microvascular abnormalities such as arteriovenous crossing signs (P = 0.003), thinner temporal retinal arteries (P arterial hypertension, an increased retinal vein-to-artery diameter ratio depends on elevated CSFP, which is correlated with blood pressure. © American Journal of Hypertension, Ltd 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Nampt/PBEF/visfatin serum levels: a new biomarker for retinal blood vessel occlusions

    Directory of Open Access Journals (Sweden)

    Kaja S

    2015-04-01

    Full Text Available Simon Kaja,1,* Anna A Shah,1,* Shamim A Haji,1,* Krishna B Patel,1 Yuliya Naumchuk,1 Alexander Zabaneh,1 Bryan C Gerdes,1 Nancy Kunjukunju,1 Nelson R Sabates,1 Michael A Cassell,1 Ron K Lord,1 Kevin P Pikey,1 Abraham Poulose,1 Peter Koulen1,21Vision Research Center, Department of Ophthalmology, 2Department of Basic Medical Science, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, USA*These authors contributed equally to this workAbstract: The main objective of the study was to quantify serum levels of nicotinamide phosphoribosyltransferase (Nampt/pre-B-Cell colony-enhancing factor 1/visfatin in subjects with a history of retinal vascular occlusions (RVOs, disease conditions characterized by pronounced ischemia, and metabolic energy deficits. A case–control study of 18 subjects with a history of RVO as well as six healthy volunteers is presented. Serum Nampt levels were quantified using a commercially available enzyme-linked immunosorbent assay kit. Serum Nampt levels were 79% lower in patients with a history of RVO compared with that in healthy volunteers (P<0.05. There was no statistically significant difference among the types of RVOs, specifically branch retinal vein occlusions (n=7, central retinal vein occlusions (n=5, hemiretinal vein occlusions (n=3, and central retinal artery occlusions (n=3; P=0.69. Further studies are needed to establish the temporal kinetics of Nampt expression and to determine whether Nampt may represent a novel biomarker to identify at-risk populations, or whether it is a druggable target with the potential to ameliorate the long-term complications associated with the condition, ie, macular edema, macular ischemia, neovascularization, and permanent loss of vision.Keywords: Nampt, PBEF, visfatin, nicotinamide phosphoribosyltransferase, pre-B-cell colony-enhancing factor, retinal artery occlusion, retinal vein occlusion, biomarker, retina, vasculature

  14. Optical Coherence Tomography Angiography in Retinal Diseases.

    Science.gov (United States)

    Chalam, K V; Sambhav, Kumar

    2016-01-01

    Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

  15. Barrier properties of cultured retinal pigment epithelium.

    Science.gov (United States)

    Rizzolo, Lawrence J

    2014-09-01

    The principal function of an epithelium is to form a dynamic barrier that regulates movement between body compartments. Each epithelium is specialized with barrier functions that are specific for the tissues it serves. The apical surface commonly faces a lumen, but the retinal pigment epithelium (RPE) appears to be unique by a facing solid tissue, the sensory retina. Nonetheless, there exists a thin (subretinal) space that can become fluid filled during pathology. RPE separates the subretinal space from the blood supply of the outer retina, thereby forming the outer blood-retinal barrier. The intricate interaction between the RPE and sensory retina presents challenges for learning how accurately culture models reflect native behavior. The challenge is heightened by findings that detail the variation of RPE barrier proteins both among species and at different stages of the life cycle. Among the striking differences is the expression of claudin family members. Claudins are the tight junction proteins that regulate ion diffusion across the spaces that lie between the cells of a monolayer. Claudin expression by RPE varies with species and life-stage, which implies functional differences among commonly used animal models. Investigators have turned to transcriptomics to supplement functional studies when comparing native and cultured tissue. The most detailed studies of the outer blood-retinal barrier have focused on human RPE with transcriptome and functional studies reported for human fetal, adult, and stem-cell derived RPE. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Retinal vessels caliber assessment in patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    N. S. Semenova

    2014-07-01

    Full Text Available Purpose: to evaluate the diagnostic capability of automated retinal vessels (RV caliber estimation for hypertensive angiopathy.Methods: this study included 146 patients (292 eyes with arterial hypertension. All the subjects underwent fundus photography and RV caliber estimation. the latter was performed using newly developed computer-based method for automated vessel detection and central retinal arteriolar and venular equivalents determination (CRAE & CRVE. Sensitivity, specificity, and reproducibility of the method were estimated.Results: the method of RV caliber assessment showed good reproducibility. the overall specificity and sensitivity were 74% and 80.77%, respectively. Computer-based method of retinal vascular caliber assessment revealed higher predictive value comparing with ophthalmoscopic assessment (AUC = 0.903 and 0.85, respectively. Retinal arteriolar and venular caliber and AVR tend to decrease with age. Higher blood pressure is associated with narrower retinal arterioles.Conclusion: Novel method of RV caliber estimation demonstrated high information value. these findings are in good agreementwith data from major population-based studies.

  17. Retinal vessels caliber assessment in patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    N. S. Semenova

    2012-01-01

    Full Text Available Purpose: to evaluate the diagnostic capability of automated retinal vessels (RV caliber estimation for hypertensive angiopathy.Methods: this study included 146 patients (292 eyes with arterial hypertension. All the subjects underwent fundus photography and RV caliber estimation. the latter was performed using newly developed computer-based method for automated vessel detection and central retinal arteriolar and venular equivalents determination (CRAE & CRVE. Sensitivity, specificity, and reproducibility of the method were estimated.Results: the method of RV caliber assessment showed good reproducibility. the overall specificity and sensitivity were 74% and 80.77%, respectively. Computer-based method of retinal vascular caliber assessment revealed higher predictive value comparing with ophthalmoscopic assessment (AUC = 0.903 and 0.85, respectively. Retinal arteriolar and venular caliber and AVR tend to decrease with age. Higher blood pressure is associated with narrower retinal arterioles.Conclusion: Novel method of RV caliber estimation demonstrated high information value. these findings are in good agreementwith data from major population-based studies.

  18. Comparison of retinal vascular geometry in obese and non-obese children.

    Directory of Open Access Journals (Sweden)

    Evelyn Li Min Tai

    Full Text Available Childhood obesity is associated with adult cardiometabolic disease. We postulate that the underlying microvascular dysfunction begins in childhood. We thus aimed to compare retinal vascular parameters between obese and non-obese children.This was a cross-sectional study involving 166 children aged 6 to 12 years old in Malaysia. Ocular examination, biometry, retinal photography, blood pressure and body mass index measurement were performed. Participants were divided into two groups; obese and non-obese. Retinal vascular parameters were measured using validated software.Mean age was 9.58 years. Approximately 51.2% were obese. Obese children had significantly narrower retinal arteriolar caliber (F(1,159 = 6.862, p = 0.010, lower arteriovenous ratio (F(1,159 = 17.412, p < 0.001, higher venular fractal dimension (F(1,159 = 4.313, p = 0.039 and higher venular curvature tortuosity (F(1,158 = 5.166, p = 0.024 than non-obese children, after adjustment for age, gender, blood pressure and axial length.Obese children have abnormal retinal vascular geometry. These findings suggest that childhood obesity is characterized by early microvascular abnormalities that precede development of overt disease. Further research is warranted to determine if these parameters represent viable biomarkers for risk stratification in obesity.

  19. Carbonic anhydrase inhibition increases retinal oxygen tension and dilates retinal vessels

    DEFF Research Database (Denmark)

    Pedersen, Daniella Bach; Koch Jensen, Peter; la Cour, Morten

    2005-01-01

    Carbonic anhydrase inhibitors (CAIs) increase blood flow in the brain and probably also in the optic nerve and retina. Additionally they elevate the oxygen tension in the optic nerve in the pig. We propose that they also raise the oxygen tension in the retina. We studied the oxygen tension in the...... in the pig retina and optic nerve before and after dorzolamide injection. Also the retinal vessel diameters during carbonic anhydrase inhibition were studied....

  20. Inner ocular blood flow responses to an acute decrease in blood pressure in resting humans

    International Nuclear Information System (INIS)

    Ikemura, Tsukasa; Kashima, Hideaki; Yamaguchi, Yuji; Miyaji, Akane; Hayashi, Naoyuki

    2015-01-01

    Whether inner ocular vessels have an autoregulatory response to acute fluctuations in blood pressure is unclear. We tried to examine the validity of acute hypotension elicited by thigh-cuff release as to assess the dynamic autoregulation in the ocular circulation. Blood flow velocity in the superior nasal and inferior temporal retinal arterioles, and in the retinal and choroidal vasculature were measured with the aid of laser speckle flowgraphy before and immediately after an acute decrease in blood pressure in 20 healthy subjects. Acute hypotension was induced by a rapid release of bilateral thigh occlusion cuffs that had been inflated to 220 mmHg for 2 min. The ratio of the relative change in retinal and choroidal blood flow velocity to the relative change in mean arterial blood pressure (MAP) was calculated. Immediately after cuff release, the MAP and blood flows in the all ocular target vessels decreased significantly from the baseline values obtained before thigh-cuff release. The ratio of the relative change in inner ocular blood flow velocity to that in the MAP exceeded 1% / %mmHg. An explicit dynamic autoregulation in inner ocular vessels cannot be demonstrated in response to an acute hypotension induced by the thigh-cuff release technique. (paper)

  1. INTERNAL LIMITING MEMBRANE PEELING-DEPENDENT RETINAL STRUCTURAL CHANGES AFTER VITRECTOMY IN RHEGMATOGENOUS RETINAL DETACHMENT.

    Science.gov (United States)

    Hisatomi, Toshio; Tachibana, Takashi; Notomi, Shoji; Koyanagi, Yoshito; Murakami, Yusuke; Takeda, Atsunobu; Ikeda, Yasuhiro; Yoshida, Shigeo; Enaida, Hiroshi; Murata, Toshinori; Sakamoto, Taiji; Sonoda, Koh-Hei; Ishibashi, Tatsuro

    2018-03-01

    To examine retinal changes after vitrectomy with internal limiting membrane (ILM) peeling, we used 3-dimensional optical coherence tomography (3D-OCT) in rhegmatogenous retinal detachment cases. The 68 eyes from 67 patients with rhegmatogenous retinal detachment were studied, including 35 detached macula cases (51%) and 33 attached macula cases. Internal limiting membrane peeling was performed with fine forceps after brilliant blue G staining. The 3D-OCT images were obtained with volume-rendering technologies from cross-sectional OCT images. The 3D-OCT detected 45 eyes (66%) with ILM peeling-dependent retinal changes, including dissociated optic nerve fiber layer appearance, dimple sign, temporal macular thinning, ILM peeling area thinning, or forceps-related retinal thinning. The ILM peeled area was detectable in only 9 eyes with 3D-OCT, whereas it was undetectable in other 59 eyes. The dissociated optic nerve fiber layer appearance was detected in 8 of the total cases (12%), and dimple signs were observed in 14 cases (21%). Forceps-related thinning was also noted in eight cases (24%) of attached macula cases and in four cases (11%) of detached macula cases. No postoperative macular pucker was noted in the observational period. The 3D-OCT clearly revealed spatial and time-dependent retinal changes after ILM peeling. The changes occurred in 2 months and remained thereafter.

  2. Detection of retinal nerve fiber layer defects in retinal fundus images using Gabor filtering

    Science.gov (United States)

    Hayashi, Yoshinori; Nakagawa, Toshiaki; Hatanaka, Yuji; Aoyama, Akira; Kakogawa, Masakatsu; Hara, Takeshi; Fujita, Hiroshi; Yamamoto, Tetsuya

    2007-03-01

    Retinal nerve fiber layer defect (NFLD) is one of the most important findings for the diagnosis of glaucoma reported by ophthalmologists. However, such changes could be overlooked, especially in mass screenings, because ophthalmologists have limited time to search for a number of different changes for the diagnosis of various diseases such as diabetes, hypertension and glaucoma. Therefore, the use of a computer-aided detection (CAD) system can improve the results of diagnosis. In this work, a technique for the detection of NFLDs in retinal fundus images is proposed. In the preprocessing step, blood vessels are "erased" from the original retinal fundus image by using morphological filtering. The preprocessed image is then transformed into a rectangular array. NFLD regions are observed as vertical dark bands in the transformed image. Gabor filtering is then applied to enhance the vertical dark bands. False positives (FPs) are reduced by a rule-based method which uses the information of the location and the width of each candidate region. The detected regions are back-transformed into the original configuration. In this preliminary study, 71% of NFLD regions are detected with average number of FPs of 3.2 per image. In conclusion, we have developed a technique for the detection of NFLDs in retinal fundus images. Promising results have been obtained in this initial study.

  3. Retinal pathology is associated with increased blood-retina barrier permeability in a diabetic and hypercholesterolaemic pig model: Beneficial effects of the LpPLA2 inhibitor Darapladib.

    Science.gov (United States)

    Acharya, Nimish K; Qi, Xin; Goldwaser, Eric L; Godsey, George A; Wu, Hao; Kosciuk, Mary C; Freeman, Theresa A; Macphee, Colin H; Wilensky, Robert L; Venkataraman, Venkat; Nagele, Robert G

    2017-05-01

    Using a porcine model of diabetes mellitus and hypercholesterolaemia, we previously showed that diabetes mellitus and hypercholesterolaemia is associated with a chronic increase in blood-brain barrier permeability in the cerebral cortex, leading to selective binding of immunoglobulin G and deposition of amyloid-beta 1-42 peptide in pyramidal neurons. Treatment with Darapladib (GlaxoSmithKline, SB480848), an inhibitor of lipoprotein-associated phospholipase-A2, alleviated these effects. Here, investigation of the effects of chronic diabetes mellitus and hypercholesterolaemia on the pig retina revealed a corresponding increased permeability of the blood-retina barrier coupled with a leak of plasma components into the retina, alterations in retinal architecture, selective IgG binding to neurons in the ganglion cell layer, thinning of retinal layers due to cell loss and increased glial fibrillary acidic protein expression in Müller cells, all of which were curtailed by treatment with Darapladib. These findings suggest that chronic diabetes mellitus and hypercholesterolaemia induces increased blood-retina barrier permeability that may be linked to altered expression of blood-retina barrier-associated tight junction proteins, claudin and occludin, leading to structural changes in the retina consistent with diabetic retinopathy. Additionally, results suggest that drugs with vascular anti-inflammatory properties, such as Darapladib, may have beneficial effects on eye diseases strongly linked to vascular abnormalities such as diabetic retinopathy and age-related macular degeneration.

  4. Comparative changes in monthly blood urea nitrogen, total protein ...

    African Journals Online (AJOL)

    The objective of this study was to determine the comparative changes in the monthly blood urea nitrogen (BUN) concentration, total protein (TP) concentration in blood serum and the body condition score of Nguni cows and heifers raised on sweetveld. Twenty-four clinically healthy animals in different parities, namely Parity ...

  5. Evaluation of the Retinal Vasculature in Hypertension and Chronic Kidney Disease in an Elderly Population of Irish Nuns.

    Science.gov (United States)

    McGowan, Amy; Silvestri, Giuliana; Moore, Evelyn; Silvestri, Vittorio; Patterson, Christopher C; Maxwell, Alexander P; McKay, Gareth J

    2015-01-01

    Chronic kidney disease (CKD) and hypertension are global public health problems associated with considerable morbidity, premature mortality and attendant healthcare costs. Previous studies have highlighted that non-invasive examination of the retinal microcirculation can detect microvascular pathology that is associated with systemic disorders of the circulatory system such as hypertension. We examined the associations between retinal vessel caliber (RVC) and fractal dimension (DF), with both hypertension and CKD in elderly Irish nuns. Data from 1233 participants in the cross-sectional observational Irish Nun Eye Study (INES) were assessed from digital photographs with a standardized protocol using computer-assisted software. Multivariate regression analyses were used to assess associations with hypertension and CKD, with adjustment for age, body mass index (BMI), refraction, fellow eye RVC, smoking, alcohol consumption, ischemic heart disease (IHD), cerebrovascular accident (CVA), diabetes and medication use. In total, 1122 (91%) participants (mean age: 76.3 [range: 56-100] years) had gradable retinal images of sufficient quality for blood vessel assessment. Hypertension was significantly associated with a narrower central retinal arteriolar equivalent (CRAE) in a fully adjusted analysis (P = 0.002; effect size = -2.16 μm; 95% confidence intervals [CI]: -3.51, -0.81 μm). No significant associations between other retinal vascular parameters and hypertension or between any retinal vascular parameters and CKD were found. Individuals with hypertension have significantly narrower retinal arterioles which may afford an earlier opportunity for tailored prevention and treatment options to optimize the structure and function of the microvasculature, providing additional clinical utility. No significant associations between retinal vascular parameters and CKD were detected.

  6. The Protective Effects of Lycium Barbarum Polysaccharides on Transient Retinal Ischemia

    Directory of Open Access Journals (Sweden)

    Di Yang

    2011-05-01

    Full Text Available Retinal ischemia/reperfusion (I/R injury leads to irreversible neuronal death, glial activation, retinal swelling and oxidative stress. It is a common feature in various ocular diseases, such as glaucoma, diabetic retinopathy and amaurosis fugax. In the present study, we aimed to evaluate the effects of Lycium Barbarum Polysaccharides (LBP in a murine retinal I/R model. Mice were orally treated with either vehicle (PBS or LBP (1mg/kg daily for 1 week before induction of retinal ischemia. Retinae were collected after 2 hours ischemia and 22 hours reperfusion. Paraffin-embedded sections were prepared for immunohistochemical analyses. Significantly fewer viable cells were found in vehicle-treated retinae comparing to LBP group. This finding was further confirmed by TUNEL assay where significantly fewer apoptotic cells were identified in LBP-treated retinae. Additionally, retinal swelling induced by retinal I/R injury in the vehicle-treated group was not observed in LBP-treated group. Moreover, intense GFAP immunoreactivity and IgG extravasation were observed in vehicle-treated group but not in LBP treated group. The results showed that pre-treatment with LBP was protective in retinal I/R injury via reducing neuronal death, apoptosis, retinal swelling, GFAP activation and blood vessel leakage. LBP may be used as a preventive agent for retinal ischemia diseases.

  7. The Protective Effects of Lycium Barbarum Polysaccharides on Transient Retinal Ischemia

    Science.gov (United States)

    Yang, Di; Li, Suk-Yee; Yeung, Chung-Man; Yu, Wing-Yan; Chang, Raymond Chuen-Chung; So, Kwok-Fai; Wong, David; Lo, Amy C. Y.

    2011-01-01

    Retinal ischemia/reperfusion (I/R) injury leads to irreversible neuronal death, glial activation, retinal swelling and oxidative stress. It is a common feature in various ocular diseases, such as glaucoma, diabetic retinopathy and amaurosis fugax. In the present study, we aimed to evaluate the effects of Lycium Barbarum Polysaccharides (LBP) in a murine retinal I/R model. Mice were orally treated with either vehicle (PBS) or LBP (1mg/kg) daily for 1 week before induction of retinal ischemia. Retinae were collected after 2 hours ischemia and 22 hours reperfusion. Paraffin-embedded sections were prepared for immunohistochemical analyses. Significantly fewer viable cells were found in vehicle-treated retinae comparing to LBP group. This finding was further confirmed by TUNEL assay where significantly fewer apoptotic cells were identified in LBP-treated retinae. Additionally, retinal swelling induced by retinal I/R injury in the vehicle-treated group was not observed in LBP-treated group. Moreover, intense GFAP immunoreactivity and IgG extravasation were observed in vehicle-treated group but not in LBP treated group. The results showed that pre-treatment with LBP was protective in retinal I/R injury via reducing neuronal death, apoptosis, retinal swelling, GFAP activation and blood vessel leakage. LBP may be used as a preventive agent for retinal ischemia diseases.

  8. Retinal detachment secondary to ocular perforation during retrobulbar Anaesthesia

    Directory of Open Access Journals (Sweden)

    Gopal Lingam

    1995-01-01

    Full Text Available The clinical characteristics and the retinal breaks associated with rhegmatogenous retinal detachments secondary to accidental globe perforation during local infiltration anaesthesia in five highly myopic eyes are presented. Retinal detachment was total with variable proliferative vitreoretinopathy. The pattern of retinal breaks was rather typical and predictable. Management involved vitreous surgery with internal tamponade by silicone oil in four eyes and perfluoropropane gas in one eye. At the last follow-up, all eyes had attached retina. One eye did not recover useful vision due to possible concurrent optic nerve damage.

  9. Propranolol transport across the inner blood-retinal barrier: potential involvement of a novel organic cation transporter.

    Science.gov (United States)

    Kubo, Yoshiyuki; Shimizu, Yoshimi; Kusagawa, Yusuke; Akanuma, Shin-Ichi; Hosoya, Ken-Ichi

    2013-09-01

    The influx transport of propranolol across the inner blood-retinal barrier (BRB) was investigated. In the in vivo analysis of carotid artery single-injection method, [(3) H]propranolol uptake by the retina was greater than that of an internal reference compound, and was reduced by several organic cations. In the in vitro uptake study, TR-iBRB2 cells, an in vitro model of the inner BRB, showed a time-, concentration-, pH- and temperature-dependent [(3) H]propranolol uptake, suggesting the involvement of a carrier-mediated transport process in the influx of propranolol across the inner BRB. In the inhibition study, various organic cations, including drugs and candidates for the treatment of the retinal diseases, inhibited the [(3) H]propranolol uptake by TR-iBRB2 cells with no significant effects by the substrates and inhibitors of well-characterized organic cation transporters, suggesting that the influx transport of propranolol is performed by a novel transporter at the inner BRB. An analysis of the relationship between the inhibitory effect and the lipophilicity of inhibitors suggests a lipophilicity-dependent inhibitory effect of amines on the [(3) H]propranolol uptake by TR-iBRB2 cells. These results showed that influx transport of propranolol across the inner BRB is performed by a carrier-mediated transport process, suggesting the involvement of a novel organic cation transporter. Copyright © 2013 Wiley Periodicals, Inc.

  10. Retinal vascular injuries and intravitreal human embryonic stem cell-derived haemangioblasts.

    Science.gov (United States)

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

    2017-09-01

    To investigate whether intravitreally applied haemangioblasts (HB) derived from human embryonic stem cells (hESCs) are helpful for the repair of vascular damage caused in animals by an oxygen-induced retinopathy (OIR), by an induced diabetic retinopathy (DR) or by an induced retinal ischaemia with subsequent reperfusion. Human embryonic stem cell-derived HBs were transplanted intravitreally into C57BL/6J mice (OIR model), into male Wistar rats with an induced DR and into male Wistar rats undergoing induced retinal ischaemia with subsequent reperfusion. Control groups of animals received an intravitreal injection of endothelial cells (ECs) or phosphate-buffered saline (PBS). We examined the vasculature integrity in the mice with OIR, the blood-retina barrier in the rats with induced DR, and retinal thickness and retinal ganglion cell density in retina flat mounts of the rats with the retinal ischaemic-reperfusion retinopathy. In the OIR model, the study group versus control groups showed a significantly (p < 0.001) smaller retinal avascular area [5.1 ± 2.7%;n = 18 animals versus 12.2 ± 2.8% (PBS group; n = 10 animals) and versus 11.8 ± 3.7% (EC group; n = 8 animals)] and less retinal neovascularization [6.3 ± 2.5%;n = 18 versus 15.2 ± 6.3% (n = 10; PBS group) and versus 15.8 ± 3.3% (n = 8; EC group)]. On retinal flat mounts, hESC-HBs were integrated into damaged retinal vessels and stained positive for PECAM (CD31) as EC marker. In the DR model, the study group versus the EC control group showed a significantly (p = 0.001) better blood-retina barrier function as measured at 2 days after the intravitreal injections [study group: 20.2 ± 12.8 μl/(g × hr); n = 6; versus EC control group: 52.9 ± 9.9 μl/(g × hr; n = 6)]. In the retinal ischaemia-reperfusion model, the groups did not differ significantly in retinal thickness and retinal ganglion cell density at 2, 5 and 7 days after baseline. By integrating into

  11. Hypoxia-ischemia and retinal ganglion cell damage

    Directory of Open Access Journals (Sweden)

    Charanjit Kaur

    2008-08-01

    Full Text Available Charanjit Kaur1, Wallace S Foulds2, Eng-Ang Ling11Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; 2Singapore Eye Research Institute, SingaporeAbstract: Retinal hypoxia is the potentially blinding mechanism underlying a number of sight-threatening disorders including central retinal artery occlusion, ischemic central retinal vein thrombosis, complications of diabetic eye disease and some types of glaucoma. Hypoxia is implicated in loss of retinal ganglion cells (RGCs occurring in such conditions. RGC death occurs by apoptosis or necrosis. Hypoxia-ischemia induces the expression of hypoxia inducible factor-1α and its target genes such as vascular endothelial growth factor (VEGF and nitric oxide synthase (NOS. Increased production of VEGF results in disruption of the blood retinal barrier leading to retinal edema. Enhanced expression of NOS results in increased production of nitric oxide which may be toxic to the cells resulting in their death. Excess glutamate release in hypoxic-ischemic conditions causes excitotoxic damage to the RGCs through activation of ionotropic and metabotropic glutamate receptors. Activation of glutamate receptors is thought to initiate damage in the retina by a cascade of biochemical effects such as neuronal NOS activation and increase in intracellular Ca2+ which has been described as a major contributing factor to RGC loss. Excess production of proinflammatory cytokines also mediates cell damage. Besides the above, free-radicals generated in hypoxic-ischemic conditions result in RGC loss because of an imbalance between antioxidant- and oxidant-generating systems. Although many advances have been made in understanding the mediators and mechanisms of injury, strategies to improve the damage are lacking. Measures to prevent neuronal injury have to be developed.Keywords: retinal hypoxia, retinal ganglion cells, glutamate receptors, neuronal injury, retina

  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. Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

    Science.gov (United States)

    Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

    2016-08-10

    We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids. 2016 BMJ Publishing Group Ltd.

  14. A Review of Algorithms for Retinal Vessel Segmentation

    Directory of Open Access Journals (Sweden)

    Monserrate Intriago Pazmiño

    2014-10-01

    Full Text Available This paper presents a review of algorithms for extracting blood vessels network from retinal images. Since retina is a complex and delicate ocular structure, a huge effort in computer vision is devoted to study blood vessels network for helping the diagnosis of pathologies like diabetic retinopathy, hypertension retinopathy, retinopathy of prematurity or glaucoma. To carry out this process many works for normal and abnormal images have been proposed recently. These methods include combinations of algorithms like Gaussian and Gabor filters, histogram equalization, clustering, binarization, motion contrast, matched filters, combined corner/edge detectors, multi-scale line operators, neural networks, ants, genetic algorithms, morphological operators. To apply these algorithms pre-processing tasks are needed. Most of these algorithms have been tested on publicly retinal databases. We have include a table summarizing algorithms and results of their assessment.

  15. Total hepatofugal portal blood flow in cirrhosis demonstrated by transhepatic portography

    International Nuclear Information System (INIS)

    Burcharth, F.; Aagaard, J.; Herlev Hospital

    1988-01-01

    We investigated 108 patients with cirrhosis of the liver and portal hypertension by percutaneous transhepatic portography to demonstrate the occurrence and frequency of total hepatofugal portal blood flow. Sixteen patients (14.8%) had a total hepatofugal portal blood flow. The aetiology of portal hypertension and the portal pressure did not differ from that in the group of patients with hepatopetal portal blood flow. A significantly higher percentage of patients in the group with hepatofugal flow had gastro-oesophageal varices (P [de

  16. The influence of venous blood flow on the retinal ganglion cell complex in patients with primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    N. I. Kurysheva

    2014-07-01

    Full Text Available Purpose: To study the influence of venous blood flow on the ganglion cell complex (GCC in patients with preperimetric and perimetric open angle glaucoma.Methods: 74 patients were included in the research. 59 eyes and 62 eyes were diagnosed with preperimetric and perimetric open angle glaucoma respectively. The mean age was 56.5±10.5 years. 22 (12 female and 10 male healthy individuals constituted the control group. The ganglion cell complex and retinal nerve fibre layer were evaluated with the help of optical coherence tomography (RTVue-100 OCT, Optovue, Inc., Fremont, CA. Ocular blood flow was measured by Color Doppler Imaging (multifunctional VOLUSON 730 ProSystem. The statistical analysis included correlation between GCC and RNFL thickness in both glaucoma groups.Results: The results showed a statistically significant reduction of venous blood flow velocity in both glaucoma groups compared to the control group. No difference in venous blood flow parameters between two glaucoma groups was found, except resistance index, which was higher in perimetric group in comparison to preperimetric group. A correlation was also obtained between venous blood flow parameters and GCC and RNFL thickness in both glaucoma groups.Conclusion: Early GCC damage in glaucoma might occur due to venous blood flow reduction. This fact may be of great value in understanding glaucoma pathogenesis and search for novel treatment options.

  17. Dexamethasone intravitreal implant downregulates PDGFR-α and upregulates caveolin-1 in experimental branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Cehofski, Lasse Jørgensen; Kruse, Anders; Magnusdottir, Sigriður Olga

    2018-01-01

    while the left control eye was given an identical injection without an implant. Fifteen days after BRVO and DEX implant intervention the retinas were excised and analyzed with tandem mass tag based mass spectrometry. A total of 26 significantly changed proteins were identified. Dexamethasone...... following an intervention with a dexamethasone (DEX) implant this study combined an experimental model of BRVO with proteomic techniques. In six Danish Landrace pigs experimental BRVO was induced in both eyes using argon laser. After inducing BRVO a DEX implant was injected in the right eye of each animal......-α and caveolin-1 were confirmed with immunohistochemistry. DEX implant intervention may inhibit PDGF signaling by decreasing the retinal level of PDGFR-α while an increased content of caveolin-1 may help maintain the integrity of the blood-retinal barrier....

  18. Retinal Vasculitis

    Science.gov (United States)

    Rosenbaum, James T.; Sibley, Cailin H.; Lin, Phoebe

    2016-01-01

    Purpose of review Ophthalmologists and rheumatologists frequently miscommunicate in consulting on patients with retinal vasculitis. This report seeks to establish a common understanding of the term, retinal vasculitis, and to review recent papers on this diagnosis. Recent findings 1) The genetic basis of some rare forms of retinal vascular disease have recently been described. Identified genes include CAPN5, TREX1, and TNFAIP3; 2) Behçet’s disease is a systemic illness that is very commonly associated with occlusive retinal vasculitis; 3) retinal imaging including fluorescein angiography and other newer imaging modalities has proven crucial to the identification and characterization of retinal vasculitis and its complications; 4) although monoclonal antibodies to IL-17A or IL-1 beta failed in trials for Behçet’s disease, antibodies to TNF alpha, either infliximab or adalimumab, have demonstrated consistent benefit in managing this disease. Interferon treatment and B cell depletion therapy via rituximab may be beneficial in certain types of retinal vasculitis. Summary Retinal vasculitis is an important entity for rheumatologists to understand. Retinal vasculitis associated with Behçet’s disease responds to monoclonal antibodies that neutralize TNF, but the many other forms of non-infectious retinal vasculitis may require alternate therapeutic management. PMID:26945335

  19. Imidazole-4-acetic acid, a new lead structure for interaction with the taurine transporter in outer blood-retinal barrier cells.

    Science.gov (United States)

    Valembois, Sophie; Krall, Jacob; Frølund, Bente; Steffansen, Bente

    2017-05-30

    Retinal diseases leading to impaired vision and ultimately blindness are mainly characterized by ischemic and hypoxic stress. Targeting the retinal ρ-containing γ-aminobutyric acid type A receptors (ρ GABA A Rs) and thereby decreasing the retinal neuronal activity has been proposed as a novel therapeutic approach. The taurine transporter (TAUT) plays a key role in the retinal transport of GABA and has been previously suggested to display a higher functional activity in the retina compared to the brain. TAUT would therefore stand as a suitable target for the selective delivery of ρ GABA A R ligands into the retina. Consequently, an in vitro model of TAUT at the outer blood-retinal barrier (BRB) was developed and characterized using the ARPE-19 cell line. Furthermore, the structural requirements of GABA A R ligands for interacting with TAUT at the BRB were investigated for a series of standard GABA A R ligands by testing their ability to inhibit the TAUT-mediated influx of taurine in ARPE-19 cells. Results showed that taurine influx was seven-fold higher when the ARPE-19 cells were cultured under hyperosmotic conditions and was demonstrated to display saturable kinetics (K m =27.7±2.2μM and J max =24.2±0.6pmol/cm 2 ·min). Furthermore, the taurine influx was significantly inhibited in a concentration-dependent manner by GABA and imidazole-4-acetic acid (IAA), which is a naturally occurring metabolite of histamine. These compounds display similar K i values of 644.2μM and 658.6μM, respectively. Moreover, IAA demonstrated higher inhibitory properties than the other tested GABA analogs: 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), 4,5,6,7-tetrahydropyrazolo[5,4-c]pyridin-3-ol (Aza-THIP), muscimol, and thiomuscimol. These studies demonstrated that IAA interacts with TAUT, which makes IAA a new lead structure in the development of new compounds, which are not only interacting with TAUT but also potent ρ GABA A R ligands. Copyright © 2017 Elsevier B

  20. Evaluation of the Retinal Vasculature in Hypertension and Chronic Kidney Disease in an Elderly Population of Irish Nuns.

    Directory of Open Access Journals (Sweden)

    Amy McGowan

    Full Text Available Chronic kidney disease (CKD and hypertension are global public health problems associated with considerable morbidity, premature mortality and attendant healthcare costs. Previous studies have highlighted that non-invasive examination of the retinal microcirculation can detect microvascular pathology that is associated with systemic disorders of the circulatory system such as hypertension. We examined the associations between retinal vessel caliber (RVC and fractal dimension (DF, with both hypertension and CKD in elderly Irish nuns.Data from 1233 participants in the cross-sectional observational Irish Nun Eye Study (INES were assessed from digital photographs with a standardized protocol using computer-assisted software. Multivariate regression analyses were used to assess associations with hypertension and CKD, with adjustment for age, body mass index (BMI, refraction, fellow eye RVC, smoking, alcohol consumption, ischemic heart disease (IHD, cerebrovascular accident (CVA, diabetes and medication use.In total, 1122 (91% participants (mean age: 76.3 [range: 56-100] years had gradable retinal images of sufficient quality for blood vessel assessment. Hypertension was significantly associated with a narrower central retinal arteriolar equivalent (CRAE in a fully adjusted analysis (P = 0.002; effect size = -2.16 μm; 95% confidence intervals [CI]: -3.51, -0.81 μm. No significant associations between other retinal vascular parameters and hypertension or between any retinal vascular parameters and CKD were found.Individuals with hypertension have significantly narrower retinal arterioles which may afford an earlier opportunity for tailored prevention and treatment options to optimize the structure and function of the microvasculature, providing additional clinical utility. No significant associations between retinal vascular parameters and CKD were detected.

  1. Total reflection x-ray analysis of metals in blood samples

    International Nuclear Information System (INIS)

    Nakamura, Takuya; Matsui, Hiroshi; Kawamata, Masaya

    2009-01-01

    The sample preparation for TXRF (total reflection X-ray fluorescence) quantitative analysis of trace elements in human blood samples was investigated. In the TXRF analysis, a solution sample is dropped and dried on a flat substrate, and then the dried residue is measured. In this case, the dried residue should be flat not to disturb X-ray total reflection on the substrate. In addition, it is required to simply measure the whole blood sample by TXRF method, although a serum is analyzed in many cases. Thus, we studied the optimum conditions of the sample preparation of the whole blood by adding the pure water to apply Hemolysis phenomenon, where blood cells are destroyed due to different of the osmotic pressure, leading to flat residue. It was found that the best S/B ratio was obtained when the whole blood was diluted 8 times with pure water. Moreover, it was investigated the influence of the surface chemical condition of the glass substrate on the shape of the dried reside of the blood sample. When the surface of the glass substrate was hydrophilic, the shape of the dried residues was not uniform, as a result, the quantitative data of TXRF analysis gave a large deviation. On the other hand, when the surface of the glass was hydrophobic, the shape of the residue was almost uniform, as a result, a good reproducibility was obtained. Another problem was an outer ring of the dried residue of the blood. This uneven ring absorbs the primary X-rays, caused to low determined quantitative data. Thus, we tried the heating way of the dropped blood sample at a high temperature of 200 degrees. In this case, the blood sample was dried immediately, and a flat homogeneous dried residue was obtained without the outer ring. Using the optimized conditions for sample preparation, human blood sample was quantitatively measured by TXRF and ICP-AES. A good agreement was obtained in TXRF and ICP-AES determinations; however, the measurement of Cl and Br will be an advantage of TXRF, because

  2. Decreased retinal capillary flow is not a mediator of the protective myopia-diabetic retinopathy relationship.

    Science.gov (United States)

    Man, Ryan Eyn Kidd; Sasongko, Muhammad Bayu; Xie, Jing; Best, William J; Noonan, Jonathan E; Lo, Tiffany Ching Shen; Wang, Jie Jin; Luu, Chi D; Lamoureux, Ecosse L

    2014-09-30

    The mechanisms supporting the protective relationship between a longer axial length (AL) and a decreased risk of diabetic retinopathy (DR) remain unclear. Previous studies have demonstrated reduced retinal blood flow in axial myopia, and it has been suggested that the compromised retinal capillaries in diabetes are less likely to leak and rupture as a result of this decreased flow. In this study, we therefore investigated if reduced retinal capillary flow (RCF) is a potential mechanism underpinning this protective relationship. Retinal capillary flow was assessed using the Heidelberg Retinal Flowmeter in 150 eyes of 85 patients with diabetes aged 18+ years from the Royal Victorian Eye and Ear Hospital and St. Vincent's Hospital (Melbourne), Australia. Axial length was measured using the Intraocular Lens Master. Diabetic retinopathy was graded from two-field retinal photographs into none, mild, moderate, and severe DR using the modified Airlie House classification system. A total of 74 out of 150 eyes (49.3%) had DR. A longer AL was associated with decreased odds of DR presence (per mm increase in AL, odds ratio [OR] 0.61, 95% confidence interval [CI] 0.41-0.91) and DR severity (OR: 0.65; 95% CI: 0.44-0.95). However, no association was found between AL and RCF (per mm increase in AL, regression coefficient [β] -1.80, 95% CI -13.50 to 9.50) or between RCF and DR (per unit increase in RCF, OR 1.00; 95% CI 0.99-1.00). Our finding suggests that diminished RCF may not be a major factor underlying the protective association between axial elongation and DR. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  3. E2f1 mediates high glucose-induced neuronal death in cultured mouse retinal explants.

    Science.gov (United States)

    Wang, Yujiao; Zhou, Yi; Xiao, Lirong; Zheng, Shijie; Yan, Naihong; Chen, Danian

    2017-10-02

    Diabetic retinopathy (DR) is the most common complication of diabetes and remains one of the major causes of blindness in the world; infants born to diabetic mothers have higher risk of developing retinopathy of prematurity (ROP). While hyperglycemia is a major risk factor, the molecular and cellular mechanisms underlying DR and diabetic ROP are poorly understood. To explore the consequences of retinal cells under high glucose, we cultured wild type or E2f1 -/- mouse retinal explants from postnatal day 8 with normal glucose, high osmotic or high glucose media. Explants were also incubated with cobalt chloride (CoCl 2 ) to mimic the hypoxic condition. We showed that, at 7 days post exposure to high glucose, retinal explants displayed elevated cell death, ectopic cell division and intact retinal vascular plexus. Cell death mainly occurred in excitatory neurons, such as ganglion and bipolar cells, which were also ectopically dividing. Many Müller glial cells reentered the cell cycle; some had irregular morphology or migrated to other layers. High glucose inhibited the hyperoxia-induced blood vessel regression of retinal explants. Moreover, inactivation of E2f1 rescued high glucose-induced ectopic division and cell death of retinal neurons, but not ectopic cell division of Müller glial cells and vascular phenotypes. This suggests that high glucose has direct but distinct effects on retinal neurons, glial cells and blood vessels, and that E2f1 mediates its effects on retinal neurons. These findings shed new light onto mechanisms of DR and the fetal retinal abnormalities associated with maternal diabetes, and suggest possible new therapeutic strategies.

  4. Focal retinal phlebitis.

    Science.gov (United States)

    Hoang, Quan V; Freund, K Bailey; Klancnik, James M; Sorenson, John A; Cunningham, Emmett T; Yannuzzi, Lawrence A

    2012-01-01

    To report three cases of solitary, focal retinal phlebitis. An observational case series. Three eyes in three patients were noted to have unilateral decreased vision, macular edema, and a focal retinal phlebitis, which was not at an arteriovenous crossing. All three patients developed a branch retinal vein occlusion at the site of inflammation. These patients had no other evidence of intraocular inflammation, including vitritis, retinitis, retinal vasculitis, or choroiditis, nor was there any systemic disorder associated with inflammation, infection, or coagulation identified. Focal retinal phlebitis appears to be an uncommon and unique entity that produces macular edema and ultimately branch retinal vein occlusion. In our patients, the focal phlebitis and venous occlusion did not occur at an arteriovenous crossing, which is the typical site for branch retinal venous occlusive disease. This suggests that our cases represent a distinct clinical entity, which starts with a focal abnormality in the wall of a retinal venule, resulting in surrounding exudation and, ultimately, ends with branch retinal vein occlusion.

  5. In-vivo imaging of blood flow dynamics using color Doppler optical coherence tomography

    Science.gov (United States)

    Yazdanfar, Siavash; Rollins, Andrew M.; Izatt, Joseph A.

    2000-04-01

    Noninvasive quantitation of blood flow in the retinal micro circulation may elucidate the progression and treatment of ocular disorders including diabetic retinopathy, age-related degeneration, and glaucoma. Color Doppler optical coherence tomography was recently introduced as a technique allowing simultaneous micron-scale resolution cross-sectional imaging of tissue micro structure and blood flow in the human retina. Here, time-resolved imaging of dynamics of blood flow profiles was performed to measure cardiac pulsatility within retinal vessels. Retinal pulsatility has been shown to decrease throughout the progression of diabetic retinopathy.

  6. Blood trihalomethane levels and the risk of total cancer mortality in US adults

    International Nuclear Information System (INIS)

    Min, Jin-Young; Min, Kyoung-Bok

    2016-01-01

    Background: Although animal data have suggested the carcinogenic activity of trihalomethanes (THMs), there is inconsistent evidence supporting the link between THM exposure and cancers in humans. Objectives: We investigated the association between specific and total blood THM levels with the risk of total cancer mortality in adults. Methods: We analyzed data from the 1999–2004 Third National Health and Nutrition Examination Survey and the Linked Mortality File of the United States. A total of 933 adults (20–59 years of age) with available blood THM levels and no missing data for other variables were included. Four different THM species (chloroform, bromodichloromethane (BDCM), dibromochloromethane (DBCM) and bromoform) were included, and the codes associated with cancer (malignant neoplasm) were C00 through C97, based on the underlying causes of death listed in the International Classification of Disease 10the Revision. Results: Compared with adults in the lowest DBCM, bromoform, and total brominated THM tertiles, those in the highest DBCM, bromoform, and total brominated THM tertiles exhibited adjusted hazard ratios (HR) of total cancer mortality of 4.97 (95% confidence interval (CI) = 1.59–15.50), 4.94 (95% CI = 1.56–15.61), and 3.42 (95% CI = 1.21–15.43) respectively. The risk of total cancer mortality was not associated with increases in blood chloroform and total THM levels. Conclusions: We found that the baseline blood THM species, particularly brominated THMs, were significantly associated with total cancer mortality in adults. Although this study should be confirm by other studies, our findings suggest a possible link between THM exposures and cancer. - Highlights: • Trihalomethanes (THM) are classified as either probable or possible carcinogens. • Limited evidence on the link between THM and the incidence of cancer in humans. • We investigated the association between blood THM levels and the risk of total cancer mortality. • High

  7. Dorzolamide increases retinal oxygen tension after branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Noergaard, Michael Hove; Bach-Holm, Daniella; Scherfig, Erik

    2008-01-01

    To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs.......To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs....

  8. Peripheral retinal degenerations and the risk of retinal detachment.

    Science.gov (United States)

    Lewis, Hilel

    2003-07-01

    To review the degenerative diseases of the peripheral retina in relationship with the risk to develop a rhegmatogenous retinal detachment and to present recommendations for use in eyes at increased risk of developing a retinal detachment. Focused literature review and author's clinical experience. Retinal degenerations are common lesions involving the peripheral retina, and most of them are clinically insignificant. Lattice degeneration, degenerative retinoschisis, cystic retinal tufts, and, rarely, zonular traction tufts, can result in a rhegmatogenous retinal detachment. Therefore, these lesions have been considered for prophylactic therapy; however, adequate studies have not been performed to date. Well-designed, prospective, randomized clinical studies are necessary to determine the benefit-risk ratio of prophylactic treatment. In the meantime, the evidence available suggests that most of the peripheral retinal degenerations should not be treated except in rare, high-risk situations.

  9. Relationship between Outer Retinal Layers Thickness and Visual Acuity in Diabetic Macular Edema

    Directory of Open Access Journals (Sweden)

    Raymond L. M. Wong

    2015-01-01

    Full Text Available Purpose. To investigate the correlation of outer retinal layers (ORL thickness and visual acuity (VA in patients with diabetic macular edema (DME. Methods. Consecutive DME patients seen at the Retina Clinic of The University of Hong Kong were recruited for OCT assessment. The ORL thickness was defined as the distance between external limiting membrane (ELM and retinal pigment epithelium (RPE at the foveal center. The correlation between total retinal thickness, ORL thickness, and vision was calculated. Results. 78 patients with DME were recruited. The mean age was 58.1 years (±11.5 years and their mean visual acuity measured with Snellen chart was 0.51 (±0.18. The correlation coefficient between total retinal thickness and visual acuity was 0.34 (P < 0.001 whereas the correlation coefficient was 0.65 between ORL thickness and visual acuity (P < 0.001. Conclusion. ORL thickness correlates better with vision than the total retinal thickness. It is a novel OCT parameter in the assessment of DME. Moreover, it could be a potential long term visual prognostic factor for patients with DME.

  10. Blood management in total hip replacement: an analysis of factors associated with allogenic blood transfusion.

    Science.gov (United States)

    Wong, Samuel; Tang, Howard; de Steiger, Richard

    2015-06-01

    The aim of this study was to audit the blood transfusion practice throughout the Epworth Healthcare Hospitals for patients undergoing primary total hip replacement (THR). We determined if blood-saving techniques were having an impact on the risk of allogenic blood transfusion and which patients were at risk of receiving allogenic blood transfusion. This study uses a retrospective audit of 787 patients who had undergone primary THR surgery at three Melbourne hospitals: Epworth Richmond, Epworth Eastern and Epworth Freemasons in 2010. Patient demographics, transfusion requirements and blood-conserving techniques were recorded. One hundred and eighty (23%) patients received allogenic blood transfusion and 18 (2.3%) patients received autologous blood transfusion. On multivariate analysis, preoperative anaemia (odds ratio (OR) 4.7, P blood transfusion. Use of spinal anaesthetic was found to be associated with lower risk of transfusion (OR 0.6, P = 0.0180) compared with general anaesthetic alone. Cell saver, acute normovolaemic haemodilution and re-infusion drain tube usage did not have a significant impact on reducing the risk of allogenic blood transfusion. Identification of patients at risk of blood transfusion, correction of preoperative anaemia and a restrictive transfusion policy are important factors to consider in effective perioperative blood management. © 2015 Royal Australasian College of Surgeons.

  11. Retinal vascular oximetry during ranibizumab treatment of central retinal vein occlusion

    DEFF Research Database (Denmark)

    Traustason, Sindri; la Cour, Morten; Larsen, Michael

    2014-01-01

    PURPOSE: To investigate the effect of intravitreal injections of the vascular endothelial growth factor inhibitor ranibizumab on retinal oxygenation in patients with central retinal vein occlusion (CRVO). METHODS: Retinal oxygen saturation in patients with CRVO was analysed using the Oxymap Retin...

  12. Bilateral acute retinal necrosis after herpetic meningitis

    Directory of Open Access Journals (Sweden)

    Katsura T

    2012-04-01

    Full Text Available Keisho Hirota1,2, Masayuki Akimoto1,3, Toshiaki Katsura21Department of Ophthalmology, Kyoto Medical Center, National Hospital Organization, 2Internal Medicine, Kyoto Medical Center, 3Clinical Research Center, Kyoto Medical Center, Kyoto, JapanPurpose: The report of a case of bilateral acute retinal necrosis after herpetic meningitis.Case report: A 47-year-old man was admitted with the chief complaint of persistent high fever and transient loss of consciousness. Although his general condition improved after intravenous acyclovir administration, the patient presented with visual loss in both eyes 4 days after admission. Visual acuity in his right eye was 20/200 and his left eye had light perception alone. Both eyes showed panretinal arteritis diagnosed as acute retinal necrosis. Panretinal photocoagulation was performed for both eyes. Progression of retinal detachment was prevented in both eyes; however, visual acuity of the left eye was totally lost because of neovascular glaucoma. Visual acuity of the right eye recovered to 20/20.Conclusion: Although cases of bilateral acute retinal necrosis have been reported after herpetic encephalitis, this condition is rare after herpetic meningitis. Prophylactic acyclovir therapy and early panretinal photocoagulation may prevent retinal detachment and improve the prognosis. Neurologists and ophthalmologists should be aware that not only herpetic encephalitis but also herpetic meningitis can lead to acute retinal necrosis within a very short interval.Keywords: acute retinal necrosis, herpetic meningitis, herpes simplex, varicella zoster virus

  13. Aortic blood flow subtraction: an alternative method for measuring total renal blood flow in conscious dogs

    DEFF Research Database (Denmark)

    Sandgaard, N C F; Andersen, J L; Holstein-Rathlou, N-H

    2002-01-01

    We have measured total renal blood flow (TRBF) as the difference between signals from ultrasound flow probes implanted around the aorta above and below the renal arteries. The repeatability of the method was investigated by repeated, continuous infusions of angiotensin II and endothelin-1 seven...... arterial blood pressure by 49% and decreased TRBF by 12%, providing an increase in renal vascular resistance of 69%. Dynamic analysis showed autoregulation of renal blood flow in the frequency range ... of TRBF by aortic blood flow subtraction is a practical and reliable method that allows direct comparison of excretory function and renal blood flow from two kidneys. The method also allows direct comparison between TRBF and flow in the caudal aorta....

  14. Segmental blood pressure after total hip replacement

    DEFF Research Database (Denmark)

    Gebuhr, Peter Henrik; Soelberg, M; Henriksen, Jens Henrik Sahl

    1992-01-01

    Twenty-nine patients due to have a total hip replacement had their systemic systolic and segmental blood pressures measured prior to operation and 1 and 6 weeks postoperatively. No patients had signs of ischemia. The segmental blood pressure was measured at the ankle and at the toes. A significant...... drop was found in all pressures 1 week postoperatively. The decrease followed the systemic pressure and was restored to normal after 6 weeks. In a group of six patients with preoperatively decreased ankle pressure, a significant transient further decrease in the ankle-toe gradient pressure was found...... on the operated side. None of the patients had symptoms from the lowered pressure. We conclude that in patients without signs of ischemia, the postoperative segmental pressure decrease is reversible and therefore not dangerous....

  15. Visual function and retinal vessel diameters during hyperthermia in man

    DEFF Research Database (Denmark)

    Jensen, Bettina Hagström; Bram, Thue; Kappelgaard, Per

    2017-01-01

    .01), a 10.6-mmHg mean reduction in diastolic blood pressure (p vein...... laser ophthalmoscopy was used to measure retinal trunk vessel diameters. Assessment was made at baseline, during hyperthermia and after cooling. RESULTS: The induction of a mean increase in core body temperature of 1.02°C was associated with a 7.15-mmHg mean reduction in systolic blood pressure (p

  16. Total Blood Loss After Transfemoral Amputations Is Twice the Intraoperative Loss

    DEFF Research Database (Denmark)

    Wied, Christian; Tengberg, Peter T; Kristensen, Morten T

    2017-01-01

    INTRODUCTION: Underestimation of the actual blood loss in patients undergoing nontraumatic transfemoral amputation (TFA) can impact negatively on outcome in these often frail patients, with very limited physiological reserves. The primary aim of this study is to estimate the total blood loss (TBL...

  17. Protection of blood retinal barrier and systemic vasculature by insulin-like growth factor binding protein-3.

    Directory of Open Access Journals (Sweden)

    Yagna P R Jarajapu

    Full Text Available Previously, we showed that insulin growth factor (IGF-1 binding protein-3 (IGFBP-3, independent of IGF-1, reduces pathological angiogenesis in a mouse model of the oxygen-induced retinopathy (OIR. The current study evaluates novel endothelium-dependent functions of IGFBP-3 including blood retinal barrier (BRB integrity and vasorelaxation. To evaluate vascular barrier function, either plasmid expressing IGFBP-3 under the regulation of an endothelial-specific promoter or a control plasmid was injected into the vitreous humor of mouse pups (P1 and compared to the non-injected eyes of the same pups undergoing standard OIR protocol. Prior to sacrifice, the mice were given an injection of horseradish peroxidase (HRP. IGFBP-3 plasmid-injected eyes displayed near-normal vessel morphology and enhanced vascular barrier function. Further, in vitro IGFBP-3 protects retinal endothelial cells from VEGF-induced loss of junctional integrity by antagonizing the dissociation of the junctional complexes. To assess the vasodilatory effects of IGFBP-3, rat posterior cerebral arteries were examined in vitro. Intraluminal IGFBP-3 decreased both pressure- and serotonin-induced constrictions by stimulating nitric oxide (NO release that were blocked by L-NAME or scavenger receptor-B1 neutralizing antibody (SRB1-Ab. Both wild-type and IGF-1-nonbinding mutant IGFBP-3 (IGFBP-3NB stimulated eNOS activity/NO release to a similar extent in human microvascular endothelial cells (HMVECs. NO release was neither associated with an increase in intracellular calcium nor decreased by Ca(2+/calmodulin-dependent protein kinase II (CamKII blockade; however, dephosphorylation of eNOS-Thr(495 was observed. Phosphatidylinositol 3-kinase (PI3K activity and Akt-Ser(473 phosphorylation were both increased by IGFBP-3 and selectively blocked by the SRB1-Ab or PI3K blocker LY294002. In conclusion, IGFBP-3 mediates protective effects on BRB integrity and mediates robust NO release to stimulate

  18. [Carrier-mediated Transport of Cationic Drugs across the Blood-Tissue Barrier].

    Science.gov (United States)

    Kubo, Yoshiyuki

    2015-01-01

    Studies of neurological dysfunction have revealed the neuroprotective effect of several cationic drugs, suggesting their usefulness in the treatment of neurological diseases. In the brain and retina, blood-tissue barriers such as blood-brain barrier (BBB) and blood-retinal barrier (BRB) are formed to restrict nonspecific solute transport between the circulating blood and neural tissues. Therefore study of cationic drug transport at these barriers is essential to achieve systemic delivery of neuroprotective agents into the neural tissues. In the retina, severe diseases such as diabetic retinopathy and macular degeneration can cause neurological dysfunction that dramatically affects patients' QOL. The BRB is formed by retinal capillary endothelial cells (inner BRB) and retinal pigment epithelial cells (outer BRB). Blood-to-retina transport of cationic drugs was investigated at the inner BRB, which is known to nourish two thirds of the retina. Blood-to-retinal transport of verapamil suggested that the barrier function of the BRB differs from that of the BBB. Moreover, carrier-mediated transport of verapamil and pyrilamine revealed the involvement of novel organic cation transporters at the inner BRB. The identified transport systems for cationic drugs are sensitive to several cationic neuroprotective and anti-angiogenic agents such as clonidine and propranolol, and the involvement of novel transporters was also suggested in their blood-to-retina transport across the inner BRB.

  19. Blood management and transfusion strategies in 600 patients undergoing total joint arthroplasty: an analysis of pre-operative autologous blood donation.

    Science.gov (United States)

    Perazzo, Paolo; Viganò, Marco; De Girolamo, Laura; Verde, Francesco; Vinci, Anna; Banfi, Giuseppe; Romagnoli, Sergio

    2013-07-01

    Blood loss during total joint arthroplasty strongly influences the time to recover after surgery and the quality of the recovery. Blood conservation strategies such as pre-operative autologous blood donation and post-operative cell salvage are intended to avoid allogeneic blood transfusions and their associated risks. Although widely investigated, the real effectiveness of these alternative transfusion practices remains controversial. The surgery reports of 600 patients undergoing total joint arthroplasty (312 hip and 288 knee replacements) were retrospectively reviewed to assess transfusion needs and related blood management at our institute. Evaluation parameters included post-operative blood loss, haemoglobin concentration measured at different time points, ASA score, and blood transfusion strategies. Autologous blood donation increased the odds of receiving a red blood cell transfusion. Reinfusion by a cell salvage system of post-operative shed blood was found to limit adverse effects in cases of severe post-operative blood loss. The peri-operative net decrease in haemoglobin concentration was higher in patients who had predeposited autologous blood than in those who had not. The strengths of this study are the high number of cases and the standardised procedures, all operations having been performed by a single orthopaedic surgeon and a single anaesthesiologist. Our data suggest that a pre-operative autologous donation programme may often be useless, if not harmful. Conversely, the use of a cell salvage system may be effective in reducing the impact of blood transfusion on a patient's physiological status. Basal haemoglobin concentration emerged as a useful indicator of transfusion probability in total joint replacement procedures.

  20. Retinal characteristics during 1 year of insulin pump therapy in type 1 diabetes

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Hommel, Eva; Munch, Inger Christine

    2016-01-01

    of CSII led to an HbA1c reduction relative to continued MDI and a small increase in retinal thickness but not to early retinopathy worsening or to changes in retinal vascular, structural or functional characteristics. Longer duration of type 1 diabetes appears to be associated with lower macular venous......PURPOSE: To investigate changes in retinal metabolism, function, structure and morphology in relation to initiation of insulin pump therapy (continuous subcutaneous insulin infusion, CSII). METHODS: Visual acuity, retinopathy level, dark adaptation kinetics, retinal and subfoveal choroidal...... thickness, macular perfusion velocities, retinal vessel diameters and blood oxygen saturations were measured at baseline and after 1, 4, 16, 32 and 52 weeks in 31 patients with type 1 diabetes who started CSII and 20 patients who continued multiple daily insulin injections (MDI). RESULTS: One year of CSII...

  1. Differential mitochondrial DNA and gene expression in inherited retinal dysplasia in miniature Schnauzer dogs.

    Science.gov (United States)

    Appleyard, Greg D; Forsyth, George W; Kiehlbauch, Laura M; Sigfrid, Kristen N; Hanik, Heather L J; Quon, Anita; Loewen, Matthew E; Grahn, Bruce H

    2006-05-01

    To investigate the molecular basis of inherited retinal dysplasia in miniature Schnauzers. Retina and retinal pigment epithelial tissues were collected from canine subjects at the age of 3 weeks. Total RNA isolated from these tissues was reverse transcribed to make representative cDNA pools that were compared for differences in gene expression by using a subtractive hybridization technique referred to as representational difference analysis (RDA). Expression differences identified by RDA were confirmed and quantified by real-time reverse-transcription PCR. Mitochondrial morphology from leukocytes and skeletal muscle of normal and affected miniature Schnauzers was examined by transmission electron microscopy. RDA screening of retinal pigment epithelial cDNA identified differences in mRNA transcript coding for two mitochondrial (mt) proteins--cytochrome oxidase subunit 1 and NADH dehydrogenase subunit 6--in affected dogs. Contrary to expectations, these identified sequences did not contain mutations. Based on the implication of mt-DNA-encoded proteins by the RDA experiments we used real-time PCR to compare the relative amounts of mt-DNA template in white blood cells from normal and affected dogs. White blood cells of affected dogs contained less than 30% of the normal amount of two specific mtDNA sequences, compared with the content of the nuclear-encoded glyceraldehyde-3-phosphate dehydrogenase (GA-3-PDH) reference gene. Retina and RPE tissue from affected dogs had reduced mRNA transcript levels for the two mitochondrial genes detected in the RDA experiment. Transcript levels for another mtDNA-encoded gene as well as the nuclear-encoded mitochondrial Tfam transcription factor were reduced in these tissues in affected dogs. Mitochondria from affected dogs were reduced in number and size and were unusually electron dense. Reduced levels of nuclear and mitochondrial transcripts in the retina and RPE of miniature Schnauzers affected with retinal dysplasia suggest that

  2. Retinal Electrophysiology Is a Viable Preclinical Biomarker for Drug Penetrance into the Central Nervous System

    Directory of Open Access Journals (Sweden)

    Jason Charng

    2016-01-01

    Full Text Available Objective. To examine whether retinal electrophysiology is a useful surrogate marker of drug penetrance into the central nervous system (CNS. Materials and Methods. Brain and retinal electrophysiology were assessed with full-field visually evoked potentials and electroretinograms in conscious and anaesthetised rats following systemic or local administrations of centrally penetrant (muscimol or nonpenetrant (isoguvacine compounds. Results. Local injections into the eye/brain bypassed the blood neural barriers and produced changes in retinal/brain responses for both drugs. In conscious animals, systemic administration of muscimol resulted in retinal and brain biopotential changes, whereas systemic delivery of isoguvacine did not. General anaesthesia confounded these outcomes. Conclusions. Retinal electrophysiology, when recorded in conscious animals, shows promise as a viable biomarker of drug penetration into the CNS. In contrast, when conducted under anaesthetised conditions confounds can be induced in both cortical and retinal electrophysiological recordings.

  3. Occlusion of retinal capillaries caused by glial cell proliferation in chronic ocular inflammation.

    Science.gov (United States)

    Bianchi, E; Ripandelli, G; Feher, J; Plateroti, A M; Plateroti, R; Kovacs, I; Plateroti, P; Taurone, S; Artico, M

    2015-01-01

    The inner blood-retinal barrier is a gliovascular unit in which glial cells surround capillary endothelial cells and regulate retinal capillaries by paracrine interactions. During chronic ocular inflammation, microvascular complications can give rise to vascular proliferative lesions, which compromise visual acuity. This pathologic remodelling caused by proliferating Müller cells determines occlusion of retinal capillaries. The aim of the present study was to identify qualitative and quantitative alterations in the retinal capillaries in patients with post-traumatic chronic ocular inflammation or post-thrombotic vascular glaucoma. Moreover, we investigated the potential role of vascular endothelial growth factor (VEGF) and pro-inflammatory cytokines in retinal inflammation. Our electron microscopy findings demonstrated that during chronic ocular inflammation, thickening of the basement membrane, loss of pericytes and endothelial cells and proliferation of Müller cells occur with irreversible occlusion of retinal capillaries. Angiogenesis takes place as part of a regenerative reaction that results in fibrosis. We believe that VEGF and pro-inflammatory cytokines may be potential therapeutic targets in the treatment of this disease although further studies are required to confirm these findings.

  4. Trypsin digest protocol to analyze the retinal vasculature of a mouse model.

    Science.gov (United States)

    Chou, Jonathan C; Rollins, Stuart D; Fawzi, Amani A

    2013-06-13

    Trypsin digest is the gold standard method to analyze the retinal vasculature (1-5). It allows visualization of the entire network of complex three-dimensional retinal blood vessels and capillaries by creating a two-dimensional flat-mount of the interconnected vascular channels after digestion of the non-vascular components of the retina. This allows one to study various pathologic vascular changes, such as microaneurysms, capillary degeneration, and abnormal endothelial to pericyte ratios. However, the method is technically challenging, especially in mice, which have become the most widely available animal model to study the retina because of the ease of genetic manipulations (6,7). In the mouse eye, it is particularly difficult to completely remove the non-vascular components while maintaining the overall architecture of the retinal blood vessels. To date, there is a dearth of literature that describes the trypsin digest technique in detail in the mouse. This manuscript provides a detailed step-by-step methodology of the trypsin digest in mouse retina, while also providing tips on troubleshooting difficult steps.

  5. Whole blood coagulation time, haematocrit, haemoglobin and total ...

    African Journals Online (AJOL)

    The study was carried out to determine the values of whole blood coagulation time (WBCT), haematocrit (HM), haemaglobin (HB) and total protein (TP) of one hundred and eighteen apparently healthy turkeys reared under an extensive management system in Zaria. The mean values for WBCT, HM, HB and TP were 1.12 ...

  6. Exudative Retinal Detachment Treatment in a Patient with Thrombotic Thrombocytopenic Purpura

    Directory of Open Access Journals (Sweden)

    Magali Sampo

    2016-02-01

    Full Text Available Purpose: We report a case of unilateral exudative retinal detachment in a patient with thrombotic thrombocytopenic purpura (TTP, without associated hypertension, successfully treated with plasmapheresis. Case Report: A 46-year-old woman with a medical history of TTP presented with unilateral exudative retinal detachment. Biological and radiological assessment eliminated other causes of exudative retinal detachment, including hypertension. Plasma exchange was performed, followed by a rapid improvement in visual acuity and total disappearance of serous detachment. Conclusion: Exudative unilateral retinal detachment is a rare complication of TTP and can be successfully treated by plasma exchange.

  7. Optical Coherence Tomography Angiography in Retinal Vascular Diseases and Choroidal Neovascularization

    Directory of Open Access Journals (Sweden)

    Rodolfo Mastropasqua

    2015-01-01

    Full Text Available Purpose. To assess the ability of optical coherence tomography-angiography (OCT-A to show and analyze retinal vascular patterns and the choroidal neovascularization (CNV in retinal vascular diseases. Methods. Seven eyes of seven consecutive patients with retinal vascular diseases were examined. Two healthy subjects served as controls. All eyes were scanned with the SD-OCT XR Avanti (Optovue Inc, Fremont CA, USA. Split spectrum amplitude decorrelation angiography algorithm was used to identify the blood flow within the tissue. Fluorescein angiography (FA and indocyanine green angiography (ICGA with Spectralis HRA + OCT (Heidelberg Engineering GmbH were performed. Results. In healthy subjects OCT-A visualized major macular vessels and detailed capillary networks around the foveal avascular zone. Patients were affected with myopic CNV (2 eyes, age-related macular degeneration related (2, branch retinal vein occlusion (BRVO (2, and branch retinal artery occlusion (BRAO (1. OCT-A images provided distinct vascular patterns, distinguishing perfused and nonperfused areas in BRVO and BRAO and recognizing the presence, location, and size of CNV. Conclusions. OCT-A provides detailed images of retinal vascular plexuses and quantitative data of pathologic structures. Further studies are warranted to define the role of OCT-A in the assessment of retinovascular diseases, with respect to conventional FA and ICG-A.

  8. STRUCTURAL ASSESSMENT OF HYPERAUTOFLUORESCENT RING IN PATIENTS WITH RETINITIS PIGMENTOSA

    Science.gov (United States)

    LIMA, LUIZ H.; CELLA, WENER; GREENSTEIN, VIVIENNE C.; WANG, NAN-KAI; BUSUIOC, MIHAI; THEODORE SMITH, R.; YANNUZZI, LAWRENCE A.; TSANG, STEPHEN H.

    2009-01-01

    Purpose To analyze the retinal structure underlying the hyperautofluorescent ring visible on fundus autofluorescence in patients with retinitis pigmentosa. Methods Twenty-four eyes of 13 patients with retinitis pigmentosa, aged 13 years to 67 years, were studied. The integrity of the photoreceptor cilia, also known as the inner/outer segment junction of the photoreceptors, the outer nuclear layer, and retinal pigment epithelium, was evaluated outside, across, and inside the ring with spectral-domain optical coherence tomography (OCT). Results Inside the foveal area, fundus autofluorescence did not detect abnormalities. Outside the ring, fundus autofluorescence revealed hypoautofluorescence compatible with the photoreceptor/retinal pigment epithelium degeneration. Spectral-domain OCT inside the ring, in the area of normal foveal fundus autofluorescence, revealed an intact retinal structure in all eyes and total retinal thickness values that were within normal limits. Across the ring, inner/outer segment junction disruption was observed and the outer nuclear layer was decreased in thickness in a centrifugal direction in all eyes. Outside the hyperautofluorescent ring, the inner/outer segment junction and the outer nuclear layer appeared to be absent and there were signs of retinal pigment epithelium degeneration. Conclusion Disruption of the inner/outer segment junction and a decrease in outer retinal thickness were found across the central hyperautofluorescent ring seen in retinitis pigmentosa. Outer segment phagocytosis by retinal pigment epithelium is necessary for the formation of an hyperautofluorescent ring. PMID:19584660

  9. RETINAL NEOVASCULARIZATION FROM A PATIENT WITH CUTIS MARMORATA TELANGIECTATICA CONGENITA.

    Science.gov (United States)

    Sassalos, Thérèse M; Fields, Taylor S; Levine, Robert; Gao, Hua

    2018-03-14

    To report a rare case of peripheral retinal neovascularization in a patient diagnosed with cutis marmorata telangiectatica congenita (CMTC). Observational case report. A 16-year-old girl was referred to clinic for retinal evaluation. The patient had a clinical diagnosis of CMTC later confirmed by skin biopsy. Examination revealed temporal peripheral retinal sheathing, as well as lattice degeneration in both eyes. Wide-field fluorescein angiogram showed substantive peripheral retinal nonperfusion with evidence of vascular leakage from areas of presumed retinal neovascularization. The patient subsequently had pan retinal photocoagulation laser treatment to each eye without complication. Cutis marmorata telangiectatica congenita is a rare vascular condition known to affect multiple organ systems including the eyes. Although ocular manifestations of CMTC are rare, instances of congenital glaucoma, suprachoroidal hemorrhage, and bilateral total retinal detachments resulting in secondary neovascular glaucoma have been reported. Our patient demonstrates the first reported findings of peripheral nonperfusion and retinal neovascularization related to CMTC in a 16-year-old girl. We propose early retinal examination, wide-field fluorescein angiogram, and early pan retinal photocoagulation laser treatment in patients with peripheral nonperfusion and retinal neovascularization from CMTC.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

  10. Tranexamic acid reduces blood loss and blood transfusions in primary total hip arthroplasty: a prospective randomized double-blind study in 40 patients

    DEFF Research Database (Denmark)

    Husted, Henrik; Blønd, Lars; Sonne-Holm, Stig

    2003-01-01

    INTRODUCTION: We performed a prospective, randomized, double-blind study on 40 patients scheduled for primary total hip arthroplasty due to arthrosis or osteonecrosis to determine the effect of tranexamic acid on per- and postoperative blood losses and on the number of blood transfusions needed...... blood losses at removal of the drain 24 hours after the operation and the number of blood transfusions. RESULTS: Patients receiving tranexamic acid had a mean peroperative blood loss of 480 mL versus 622 mL in patients receiving placebo (p = 0.3), a postoperative blood loss of 334 mL versus 609 mL (p...... = 0.001), a total blood loss of 814 mL versus 1231 mL (p = 0.001) and a total need for 4 blood transfusions versus 25 (p = 0.04). No patient in either group had symptoms of deep venous thrombosis, pulmonary embolism or prolonged wound drainage. INTERPRETATION: Transemic acid is effective in reducing...

  11. Retinal vascular segmentation using superpixel-based line operator and its application to vascular topology estimation.

    Science.gov (United States)

    Na, Tong; Xie, Jianyang; Zhao, Yitian; Zhao, Yifan; Liu, Yue; Wang, Yongtian; Liu, Jiang

    2018-05-09

    Automatic methods of analyzing of retinal vascular networks, such as retinal blood vessel detection, vascular network topology estimation, and arteries/veins classification are of great assistance to the ophthalmologist in terms of diagnosis and treatment of a wide spectrum of diseases. We propose a new framework for precisely segmenting retinal vasculatures, constructing retinal vascular network topology, and separating the arteries and veins. A nonlocal total variation inspired Retinex model is employed to remove the image intensity inhomogeneities and relatively poor contrast. For better generalizability and segmentation performance, a superpixel-based line operator is proposed as to distinguish between lines and the edges, thus allowing more tolerance in the position of the respective contours. The concept of dominant sets clustering is adopted to estimate retinal vessel topology and classify the vessel network into arteries and veins. The proposed segmentation method yields competitive results on three public data sets (STARE, DRIVE, and IOSTAR), and it has superior performance when compared with unsupervised segmentation methods, with accuracy of 0.954, 0.957, and 0.964, respectively. The topology estimation approach has been applied to five public databases (DRIVE,STARE, INSPIRE, IOSTAR, and VICAVR) and achieved high accuracy of 0.830, 0.910, 0.915, 0.928, and 0.889, respectively. The accuracies of arteries/veins classification based on the estimated vascular topology on three public databases (INSPIRE, DRIVE and VICAVR) are 0.90.9, 0.910, and 0.907, respectively. The experimental results show that the proposed framework has effectively addressed crossover problem, a bottleneck issue in segmentation and vascular topology reconstruction. The vascular topology information significantly improves the accuracy on arteries/veins classification. © 2018 American Association of Physicists in Medicine.

  12. Exome sequencing identifies compound heterozygous mutations in CYP4V2 in a pedigree with retinitis pigmentosa.

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    Yun Wang

    Full Text Available Retinitis pigmentosa (RP is a heterogeneous group of progressive retinal degenerations characterized by pigmentation and atrophy in the mid-periphery of the retina. Twenty two subjects from a four-generation Chinese family with RP and thin cornea, congenital cataract and high myopia is reported in this study. All family members underwent complete ophthalmologic examinations. Patients of the family presented with bone spicule-shaped pigment deposits in retina, retinal vascular attenuation, retinal and choroidal dystrophy, as well as punctate opacity of the lens, reduced cornea thickness and high myopia. Peripheral venous blood was obtained from all patients and their family members for genetic analysis. After mutation analysis in a few known RP candidate genes, exome sequencing was used to analyze the exomes of 3 patients III2, III4, III6 and the unaffected mother II2. A total of 34,693 variations shared by 3 patients were subjected to several filtering steps against existing variation databases. Identified variations were verified in the rest family members by PCR and Sanger sequencing. Compound heterozygous c.802-8_810del17insGC and c.1091-2A>G mutations of the CYP4V2 gene, known as genetic defects for Bietti crystalline corneoretinal dystrophy, were identified as causative mutations for RP of this family.

  13. Retinal vascular speed prematurity requiring treatment.

    Science.gov (United States)

    Solans Pérez de Larraya, Ana M; Ortega Molina, José M; Fernández, José Uberos; Escudero Gómez, Júlia; Salgado Miranda, Andrés D; Chaves Samaniego, Maria J; García Serrano, José L

    2018-03-01

    To analyse the speed of temporal retinal vascularisation in preterm infants included in the screening programme for retinopathy of prematurity. A total of 185 premature infants were studied retrospectively between 2000 and 2017 in San Cecilio University Hospital of Granada, Spain. The method of binocular indirect ophthalmoscopy with indentation was used for the examination. The horizontal disc diameter was used as a unit of length. Speed of temporal retinal vascularisation (disc diameter/week) was calculated as the ratio between the extent of temporal retinal vascularisation (disc diameter) and the time in weeks. The weekly temporal retinal vascularisation (0-1.25 disc diameter/week, confidence interval) was significantly higher in no retinopathy of prematurity (0.73 ± 0.22 disc diameter/week) than in stage 1 retinopathy of prematurity (0.58 ± 0.22 disc diameter/week). It was also higher in stage 1 than in stages 2 (0.46 ± 0.14 disc diameter/week) and 3 of retinopathy of prematurity (0.36 ± 0.18 disc diameter/week). The rate of temporal retinal vascularisation (disc diameter/week) decreases when retinopathy of prematurity stage increases. The area under the receiver operating characteristic curve was 0.85 (95% confidence interval: 0.79-0.91) for retinopathy of prematurity requiring treatment versus not requiring treatment. The best discriminative cut-off point was a speed of retinal vascularisation prematurity may be required. However, before becoming a new standard of care for treatment, it requires careful documentation, with agreement between several ophthalmologists.

  14. Estimating retinal vascular permeability using the adiabatic approximation to the tissue homogeneity model with fluorescein videoangiography

    Science.gov (United States)

    Tichauer, Kenneth M.; Osswald, Christian R.; Dosmar, Emily; Guthrie, Micah J.; Hones, Logan; Sinha, Lagnojita; Xu, Xiaochun; Mieler, William F.; St. Lawrence, Keith; Kang-Mieler, Jennifer J.

    2015-06-01

    Clinical symptoms of diabetic retinopathy are not detectable until damage to the retina reaches an irreversible stage, at least by today's treatment standards. As a result, there is a push to develop new, "sub-clinical" methods of predicting the onset of diabetic retinopathy before the onset of irreversible damage. With diabetic retinopathy being associated with the accumulation of long-term mild damage to the retinal vasculature, retinal blood vessel permeability has been proposed as a key parameter for detecting preclinical stages of retinopathy. In this study, a kinetic modeling approach used to quantify vascular permeability in dynamic contrast-enhanced medical imaging was evaluated in noise simulations and then applied to retinal videoangiography data in a diabetic rat for the first time to determine the potential for this approach to be employed clinically as an early indicator of diabetic retinopathy. Experimental levels of noise were found to introduce errors of less than 15% in estimates of blood flow and extraction fraction (a marker of vascular permeability), and fitting of rat retinal fluorescein angiography data provided stable maps of both parameters.

  15. Visual BOLD Response in Late Blind Subjects with Argus II Retinal Prosthesis.

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    E Castaldi

    2016-10-01

    Full Text Available Retinal prosthesis technologies require that the visual system downstream of the retinal circuitry be capable of transmitting and elaborating visual signals. We studied the capability of plastic remodeling in late blind subjects implanted with the Argus II Retinal Prosthesis with psychophysics and functional MRI (fMRI. After surgery, six out of seven retinitis pigmentosa (RP blind subjects were able to detect high-contrast stimuli using the prosthetic implant. However, direction discrimination to contrast modulated stimuli remained at chance level in all of them. No subject showed any improvement of contrast sensitivity in either eye when not using the Argus II. Before the implant, the Blood Oxygenation Level Dependent (BOLD activity in V1 and the lateral geniculate nucleus (LGN was very weak or absent. Surprisingly, after prolonged use of Argus II, BOLD responses to visual input were enhanced. This is, to our knowledge, the first study tracking the neural changes of visual areas in patients after retinal implant, revealing a capacity to respond to restored visual input even after years of deprivation.

  16. Overexpression of Pax6 results in microphthalmia, retinal dysplasia and defective retinal ganglion cell axon guidance

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    Jeffery Glen

    2008-05-01

    Full Text Available Abstract Background The transcription factor Pax6 is expressed by many cell types in the developing eye. Eyes do not form in homozygous loss-of-function mouse mutants (Pax6Sey/Sey and are abnormally small in Pax6Sey/+ mutants. Eyes are also abnormally small in PAX77 mice expressing multiple copies of human PAX6 in addition to endogenous Pax6; protein sequences are identical in the two species. The developmental events that lead to microphthalmia in PAX77 mice are not well-characterised, so it is not clear whether over- and under-expression of Pax6/PAX6 cause microphthalmia through similar mechanisms. Here, we examined the consequences of over-expression for the eye and its axonal connections. Results Eyes form in PAX77+/+ embryos but subsequently degenerate. At E12.5, we found no abnormalities in ocular morphology, retinal cell cycle parameters and the incidence of retinal cell death. From E14.5 on, we observed malformations of the optic disc. From E16.5 into postnatal life there is progressively more severe retinal dysplasia and microphthalmia. Analyses of patterns of gene expression indicated that PAX77+/+ retinae produce a normal range of cell types, including retinal ganglion cells (RGCs. At E14.5 and E16.5, quantitative RT-PCR with probes for a range of molecules associated with retinal development showed only one significant change: a slight reduction in levels of mRNA encoding the secreted morphogen Shh at E16.5. At E16.5, tract-tracing with carbocyanine dyes in PAX77+/+ embryos revealed errors in intraretinal navigation by RGC axons, a decrease in the number of RGC axons reaching the thalamus and an increase in the proportion of ipsilateral projections among those RGC axons that do reach the thalamus. A survey of embryos with different Pax6/PAX6 gene dosage (Pax6Sey/+, Pax6+/+, PAX77+ and PAX77+/+ showed that (1 the total number of RGC axons projected by the retina and (2 the proportions that are sorted into the ipsilateral and

  17. AN EFFICIENT TECHNIQUE FOR RETINAL VESSEL SEGMENTATION AND DENOISING USING MODIFIED ISODATA AND CLAHE

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    Khan Bahadar Khan

    2016-11-01

    Full Text Available Retinal damage caused due to complications of diabetes is known as Diabetic Retinopathy (DR. In this case, the vision is obscured due to the damage of retinal tinny blood vessels of the retina. These tinny blood vessels may cause leakage which affect the vision and can lead to complete blindness. Identification of these new retinal vessels and their structure is essential for analysis of DR. Automatic blood vessels segmentation plays a significant role to assist subsequent automatic methodologies that aid to such analysis. In literature most of the people have used computationally hungry a strong preprocessing steps followed by a simple thresholding and post processing, But in our proposed technique we utilize an arrangement of  light pre-processing which consists of Contrast Limited Adaptive Histogram Equalization (CLAHE for contrast enhancement, a difference image of green channel from its Gaussian blur filtered image to remove local noise or geometrical object, Modified Iterative Self Organizing Data Analysis Technique (MISODATA for segmentation of vessel and non-vessel pixels based on global and local thresholding, and a strong  post processing using region properties (area, eccentricity to eliminate the unwanted region/segment, non-vessel pixels and noise that never been used to reject misclassified foreground pixels. The strategy is tested on the publically accessible DRIVE (Digital Retinal Images for Vessel Extraction and STARE (STructured Analysis of the REtina databases. The performance of proposed technique is assessed comprehensively and the acquired accuracy, robustness, low complexity and high efficiency and very less computational time that make the method an efficient tool for automatic retinal image analysis. Proposed technique perform well as compared to the existing strategies on the online available databases in term of accuracy, sensitivity, specificity, false positive rate, true positive rate and area under receiver

  18. Continuing versus discontinuing antiplatelet drugs, vasodilators, and/or cerebral ameliorators on perioperative total blood loss in total knee arthroplasty without pneumatic tourniquet

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    Sachiyuki Tsukada, MD

    2018-03-01

    Full Text Available Background: Although studies have supported the utility of perioperative continuation of antiplatelet drugs, vasodilators, and cerebral ameliorators in most procedures, no study compared total volume of blood loss after total knee arthroplasty (TKA in patients continuing and discontinuing these drugs. Methods: We retrospectively reviewed 266 consecutive patients undergoing TKA, and included 67 patients (25.2% taking antiplatelet drugs, vasodilators, or cerebral ameliorators in this study. All TKAs were performed without a pneumatic tourniquet. The primary outcome was perioperative total blood loss calculated from blood volume and change in hemoglobin. As subgroup analysis, we compared perioperative total blood loss in patients taking antiplatelet drugs. Results: There was no significant difference between the continuing group (n = 38 and discontinuing group (n = 29 in terms of the perioperative total blood loss (1025 ± 364 vs 1151 ± 327 mL, respectively; mean difference 126 mL; 95% confidence interval −45 to 298 mL; P = .15. No major bleeding or thrombotic events occurred in either group until postoperative 3-month follow-up. In patients taking antiplatelet drugs (n = 51, no significant difference was observed in the total blood loss between the continuing group (n = 30 and discontinuing group (n = 21 (1056 ± 287 vs 1151 ± 305 mL, respectively; mean difference 95 mL; 95% confidence interval −75 to 264 mL; P = .27. Conclusions: No significant differences in terms of perioperative total blood loss were observed between patients continuing and discontinuing study drugs. Continuing these drugs may be preferable in the perioperative period of TKA. Keywords: Knee, Primary arthroplasty, Bleeding events, Thrombotic events, Noncardiac surgery

  19. Retinal vasculitis.

    Science.gov (United States)

    Abu El-Asrar, Ahmed M; Herbort, Carl P; Tabbara, Khalid F

    2005-12-01

    Retinal vasculitis is a sight-threatening intraocular inflammation affecting the retinal vessels. It may occur as an isolated ocular condition, as a manifestation of infectious or neoplastic disorders, or in association with a systemic inflammatory disease. The search for an underlying etiology should be approached in a multidisciplinary fashion based on a thorough history, review of systems, physical examination, and laboratory evaluation. Discrimination between infectious and noninfectious etiologies of retinal vasculitis is important because their treatment is different. This review is based on recently published articles on retinal vasculitis and deals with its clinical diagnosis, its link with systemic diseases, and its laboratory investigation.

  20. Association of systemic risk factors with the severity of retinal hard exudates in a north Indian population with type 2 diabetes

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    Sachdev N

    2010-01-01

    Full Text Available Background: The various risk factors for diabetic retinopathy and its spectrum are still poorly understood in the Indian population. Aims: To study the association of various systemic risk factors with retinal hard exudates in type 2 diabetic north Indian patients and to measure the incidence of dyslipidemia in them. Settings and Design: A tertiary-hospital-based cross-sectional study. Materials and Methods: An observational case-study which included 180 type 2 diabetic patients (180 eyes of nonproliferative diabetic retinopathy (NPDR with clinically significant macular edema (CSME. In these patients the retinal hard exudates were graded on a central 500 fundus picture using modified Airlie House classification and divided into three groups of absent or minimal hard exudates (Group 1, hard exudates present (Group 2 and prominent hard exudates (Group 3. Their association with various risk factors, namely the age of onset of diabetes and its duration, gender, insulin therapy, and various systemic parameters like hypertension, blood hemoglobin, glycosylated hemoglobin, serum (s. creatinine levels, 24-h proteinuria and complete lipid profile including total s. cholesterol, low-density lipoprotein cholesterol (LDL, high-density lipoprotein cholesterol (HDL, very low-density lipoprotein cholesterol (VLDL and s. triglyceride (TG was studied. The incidence of dyslipidemia was also calculated among these groups of patients. Statistical Analysis: ANOVA test, linear regression analysis and Spearman′s correlation test. Results: On univariate analysis, the retinal hard exudates were significantly associated with s. creatinine (P=0.016, systolic blood pressure (P=0.014, s. cholesterol (P < 0.001, s. LDL (P=0.008 and s. TG (P=0.013 levels. While on linear regression analysis, s. cholesterol (P < 0.001 and s. LDL cholesterol (P=0.028 were found to be independent risk factors affecting the density of retinal hard exudates. On Spearman′s correlation test, the

  1. Retinal vessel diameters decrease with macular ganglion cell layer thickness in autosomal dominant optic atrophy and in healthy subjects

    DEFF Research Database (Denmark)

    Rönnbäck, Cecilia; Grønskov, Karen; Larsen, Michael

    2014-01-01

    diameters (central retinal artery equivalent, CRAE, and central retinal vein equivalent, CRVE). Statistical analysis was corrected for age, gender, spherical equivalent refraction, axial length and mean arterial blood pressure (MABP) in a mixed model analysis. RESULTS: Retinal arteries and veins were...... ganglion cell-inner plexiform layer (GC-IPL) thickness (p = 0.0017 and p = 0.0057, respectively). CONCLUSION: Narrow retinal arteries and veins were associated not only with the severity of ADOA but with ganglion cell volume in patients with ADOA and in healthy subjects. This suggests that narrow vessels...

  2. Summarising the retinal vascular calibres in healthy, diabetic and diabetic retinopathy eyes.

    Science.gov (United States)

    Leontidis, Georgios; Al-Diri, Bashir; Hunter, Andrew

    2016-05-01

    Retinal vessel calibre has been found to be an important biomarker of several retinal diseases, including diabetic retinopathy (DR). Quantifying the retinal vessel calibres is an important step for estimating the central retinal artery and vein equivalents. In this study, an alternative method to the already established branching coefficient (BC) is proposed for summarising the vessel calibres in retinal junctions. This new method combines the mean diameter ratio with an alternative to Murray׳s cube law exponent, derived by the fractal dimension,experimentally, and the branch exponent of cerebral vessels, as has been suggested in previous studies with blood flow modelling. For the above calculations, retinal images from healthy, diabetic and DR subjects were used. In addition, the above method was compared with the BC and was also applied to the evaluation of arteriovenous ratio as a biomarker of progression from diabetes to DR in four consecutive years, i.e. three/two/one years before the onset of DR and the first year of DR. Moreover, the retinal arteries and veins around the optic nerve head were also evaluated. The new approach quantifies the vessels more accurately. The decrease in terms of the mean absolute percentage error was between 0.24% and 0.49%, extending at the same time the quantification beyond healthy subjects. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Interventions for asymptomatic retinal breaks and lattice degeneration for preventing retinal detachment.

    Science.gov (United States)

    Wilkinson, Charles P

    2014-09-05

    Asymptomatic retinal breaks and lattice degeneration are visible lesions that are risk factors for later retinal detachment. Retinal detachments occur when fluid in the vitreous cavity passes through tears or holes in the retina and separates the retina from the underlying retinal pigment epithelium. Creation of an adhesion surrounding retinal breaks and lattice degeneration, with laser photocoagulation or cryotherapy, has been recommended as an effective means of preventing retinal detachment. This therapy is of value in the management of retinal tears associated with the symptoms of flashes and floaters and persistent vitreous traction upon the retina in the region of the retinal break, because such symptomatic retinal tears are associated with a high rate of progression to retinal detachment. Retinal tears and holes unassociated with acute symptoms and lattice degeneration are significantly less likely to be the sites of retinal breaks that are responsible for later retinal detachment. Nevertheless, treatment of these lesions frequently is recommended, in spite of the fact that the effectiveness of this therapy is unproven. The objective of this review was to assess the effectiveness and safety of techniques used to treat asymptomatic retinal breaks and lattice degeneration for the prevention of retinal detachment. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 2), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to February 2014), EMBASE (January 1980 to February 2014), PubMed (January 1948 to February 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials

  4. Treatment of Retinal Separation in HIV-infected Patients with Cytomegalovirus Retinitis

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    A. L. Onischenko

    2017-01-01

    Full Text Available HIV infection — is a socially significant problem for many countries, as the infected die in an average of 10-11 years due to the immunodeficiency virus. Up to 20% of patients with AIDS lose their sight because of cytomegalovirus retinitis (CMV retinitis, which occurs in 70% of HIV-infected people. In some patients with HIV infection blindness occurs because of acute retinal necrosis of CMV etiology. The algorithm of CMV retinitis treatment in HIV-infected patients is described in modern manuals (ganciclovir, valganciclovir, foscarnet and others on the background of antiretroviral therapy, but the tactics of treatment of retinal separation in these patients is not clearly defined. It may be “wait and see”, providing conservative treatment with antiviral drugs, and the active tactics — vitreoretinal surgery. In this article the authors present their personal clinical observations of three HIV-infected patients with CMV retinitis at the age of 8 to 36 years with a detailed analysis of the clinical data and the results of the laboratory tests. In particular, the authors give their own results of intravitreal introduction of ganciclovir in patients with CMV retinitis. Given the poor prognosis for the life of these patients, the authors put a deontological question of justification of active treatment of retinal separation in AIDS patients with CMV retinitis.

  5. Aag-initiated base excision repair drives alkylation-induced retinal degeneration in mice.

    Science.gov (United States)

    Meira, Lisiane B; Moroski-Erkul, Catherine A; Green, Stephanie L; Calvo, Jennifer A; Bronson, Roderick T; Shah, Dharini; Samson, Leona D

    2009-01-20

    Vision loss affects >3 million Americans and many more people worldwide. Although predisposing genes have been identified their link to known environmental factors is unclear. In wild-type animals DNA alkylating agents induce photoreceptor apoptosis and severe retinal degeneration. Alkylation-induced retinal degeneration is totally suppressed in the absence of the DNA repair protein alkyladenine DNA glycosylase (Aag) in both differentiating and postmitotic retinas. Moreover, transgenic expression of Aag activity restores the alkylation sensitivity of photoreceptors in Aag null animals. Aag heterozygotes display an intermediate level of retinal degeneration, demonstrating haploinsufficiency and underscoring that Aag expression confers a dominant retinal degeneration phenotype.

  6. Relationship among visual field, blood flow, and neural structure measurements in glaucoma.

    Science.gov (United States)

    Hwang, John C; Konduru, Ranjith; Zhang, Xinbo; Tan, Ou; Francis, Brian A; Varma, Rohit; Sehi, Mitra; Greenfield, David S; Sadda, Srinivas R; Huang, David

    2012-05-17

    To determine the relationship among visual field, neural structural, and blood flow measurements in glaucoma. Case-control study. Forty-seven eyes of 42 patients with perimetric glaucoma were age-matched with 27 normal eyes of 27 patients. All patients underwent Doppler Fourier-domain optical coherence tomography to measure retinal blood flow and standard glaucoma evaluation with visual field testing and quantitative structural imaging. Linear regression analysis was performed to analyze the relationship among visual field, blood flow, and structure, after all variables were converted to logarithmic decibel scale. Retinal blood flow was reduced in glaucoma eyes compared to normal eyes (P flow and structural loss of rim area and retinal nerve fiber layer (RNFL). There was no correlation or paradoxical correlation between blood flow and structure. Multivariate regression analysis revealed that reduced blood flow and structural loss are independent predictors of visual field loss. Each dB decrease in blood flow was associated with at least 1.62 dB loss in mean deviation (P ≤ 0.001), whereas each dB decrease in rim area and RNFL was associated with 1.15 dB and 2.56 dB loss in mean deviation, respectively (P ≤ 0.03). There is a close link between reduced retinal blood flow and visual field loss in glaucoma that is largely independent of structural loss. Further studies are needed to elucidate the causes of the vascular dysfunction and potential avenues for therapeutic intervention. Blood flow measurement may be useful as an independent assessment of glaucoma severity.

  7. Establishing an experimental rat model of photodynamically-induced retinal vein occlusion using erythrosin B

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    Wei Chen

    2014-04-01

    Full Text Available AIM:To develop a reliable, reproducible rat model of retinal vein occlusion (RVO with a novel photosensitizer (erythrosin B and study the cellular responses in the retina.METHODS:Central and branch RVOs were created in adult male rats via photochemically-induced ischemia. Retinal changes were monitored via color fundus photography and fluorescein angiography at 1 and 3h, and 1, 4, 7, 14, and 21d after irradiation. Tissue slices were evaluated histopathologically. Retinal ganglion cell survival at different times after RVO induction was quantified by nuclear density count. Retinal thickness was also observed.RESULTS:For all rats in both the central and branch RVO groups, blood flow ceased immediately after laser irradiation and retinal edema was evident at one hour. The retinal detachment rate was 100% at 3h and developed into bullous retinal detachment within 24h. Retinal hemorrhages were not observed until 24h. Clearance of the occluded veins at 7d was observed by fluorescein angiography. Disease manifestation in the central RVO eyes was more severe than in the branch RVO group. A remarkable reduction in the ganglion cell count and retinal thickness was observed in the central RVO group by 21d, whereas moderate changes occurred in the branch RVO group.CONCLUSION: Rat RVO created by photochemically-induced ischemia using erythrosin B is a reproducible and reliable animal model for mimicking the key features of human RVO. However, considering the 100% rate of retinal detachment, this animal model is more suitable for studying RVO with chronic retinal detachment.

  8. Elevated albumin excretion and retinal changes in children with type 1 diabetes are related to long-term poor blood glucose control

    DEFF Research Database (Denmark)

    Nørgaard, K; Storm, Birgit Kjærside; Graae, M

    1989-01-01

    patients were proteinuric (greater than 300 mg 24 h-1) (2%). Retinal morphology was evaluated by colour fundus photography. Background retinopathy was more frequent in the group with elevated albumin excretion (71%) than in a matched normoalbuminuric group (20%, 2p less than 0.001). Long-term blood glucose......All diabetic children (n = 113) under 19 years old and with more than 2 years of diabetes attending the Steno Memorial Hospital in 1987 were studied. Normal urinary albumin excretion (less than 30 mg 24 h-1) was found in 96 patients (85%), 15 had microalbuminuria (30-300 mg 24 h-1) (13%), and 2...

  9. Total and regional blood flows in vascularized skeletal muscle grafts in rabbits

    International Nuclear Information System (INIS)

    Burton, H.W.; Stevenson, T.R.; Dysko, R.C.; Gallagher, K.P.; Faulkner, J.A.

    1988-01-01

    The transplantation of whole skeletal muscles is a common clinical procedure. Although atypical blood flows have been reported in small free muscle grafts, the blood flow of large neurovascular-intact (NVI) and neurovascular-anastomosed (NVA) grafts have not been measured. Because the maximum specific force (N/cm 2 ) of NVI and NVA grafts is 65% that of control muscles, we hypothesized that total and regional blood flows of NVI and NVA grafts at rest and during twitch contractions are significantly lower than lower flows of control muscles. In rabbits, blood flows of control rectus femoris (RFM) muscles and NVI and NVA grafts of RFM muscles were measured by the radioactive-microsphere technique. Total blood flows in grafts were not different from the control RFM muscle values, except for a higher resting flow in NVA grafts and a lower flow at 3 Hz in NVI grafts. Minor variations in regional flows were observed. We conclude that the operative procedures of grating and repair of blood vessels affect the vascular bed of muscles minimally, and the deficits observed in grafts do not arise from inadequate perfusion

  10. An Automatic Cognitive Graph-Based Segmentation for Detection of Blood Vessels in Retinal Images

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    Rasha Al Shehhi

    2016-01-01

    Full Text Available This paper presents a hierarchical graph-based segmentation for blood vessel detection in digital retinal images. This segmentation employs some of perceptual Gestalt principles: similarity, closure, continuity, and proximity to merge segments into coherent connected vessel-like patterns. The integration of Gestalt principles is based on object-based features (e.g., color and black top-hat (BTH morphology and context and graph-analysis algorithms (e.g., Dijkstra path. The segmentation framework consists of two main steps: preprocessing and multiscale graph-based segmentation. Preprocessing is to enhance lighting condition, due to low illumination contrast, and to construct necessary features to enhance vessel structure due to sensitivity of vessel patterns to multiscale/multiorientation structure. Graph-based segmentation is to decrease computational processing required for region of interest into most semantic objects. The segmentation was evaluated on three publicly available datasets. Experimental results show that preprocessing stage achieves better results compared to state-of-the-art enhancement methods. The performance of the proposed graph-based segmentation is found to be consistent and comparable to other existing methods, with improved capability of detecting small/thin vessels.

  11. Effects of nuclear factor κB expression on retinal neovascularization and apoptosis in a diabetic retinopathy rat model

    Institute of Scientific and Technical Information of China (English)

    Ning; Jiang; Xiao-Long; Chen; Hong-Wei; Yang; Yu-Ru; Ma

    2015-01-01

    AIM: To investigate the expression and role of nuclear factor κB(NF-κB) in diabetic retinopathy(DR) and its relationship with neovascularization and retinal cell apoptosis. METHODS: A total of 80 male Wistar rats were randomly assigned to control(4, 8, 12 and 16 wk, n =10 in each group) and diabetes mellitus(DM) groups(4, 8, 12 and 16wk, n =10 in each group). A diabetic rat model was established by intraperitoneal injection of streptozotocin(60 mg/kg). After 4, 8, 12 and 16 wk, rats were sacrificed.Retinal layers and retinal neovascularization growth were stained with hematoxylin-eosin and examined under light microscopy. Cell apoptosis in the retina was detected by Td T-mediated d UTP nick end labeling, and NF-κB distribution and expression in the retina was determined using immunohistochemistry. RESULTS: DM model success rate up to 100%.Diabetes model at each time point after the experimental groupcompared with the control group, the blood glucose was significantly increased, decreased body weight, each time point showed significant differences compared with the control group(P <0.01). After 12 wk other pathological changes in the retina of diabetic rats were observed; after 16 wk, neovascularization were observed. After 1mo, retinal cell apoptosis was observed.Compared with the control group, NF-κB expression in the DM group significantly increased with disease duration.CONCLUSION: With the prolonging of DM progression,the expression NF-κB increases. NF-κB may be related to retinal cell apoptosis and neovascularization.

  12. Posterior vitreous detachment - prevalence of and risk factors for retinal tears

    Directory of Open Access Journals (Sweden)

    Bond-Taylor M

    2017-09-01

    Full Text Available Martin Bond-Taylor,1 Gunnar Jakobsson,1,2 Madeleine Zetterberg1,2 1Department of Ophthalmology, Sahlgrenska University Hospital, Mölndal, 2Department of Clinical Neuroscience/Ophthalmology, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden Purpose: The present study aimed to describe clinical characteristics of patients with posterior vitreous detachment (PVD, to determine the prevalence of retinal tears in PVD patients, and to find predictors for retinal tears in this patient group. Methods: Retrospective analysis of medical records on patients diagnosed with PVD, retinal tears, or vitreous hemorrhage at the Department of Ophthalmology at Sahlgrenska University Hospital, a tertiary eye center. Results: Between February and July 2009, 365 patients consulted the Department of Ophthalmology for PVD-related symptoms. The incidence of retinal tears was 14.5% (n=53 and that of vitreous and/or retinal hemorrhage was 22.7% (n=83. For analysis of possible predictors for complications to PVD, patients diagnosed with retinal tears or vitreous hemorrhage between May and July 2009 were also included in the study, resulting in a total of 426 patients. Predictors of a retinal tear were symptoms of visual impairment (P=0.024, the presence of vitreous or retinal hemorrhage at examination (P<0.001, and a duration of symptoms for <24 hours (P=0.004. Symptoms of flashes did not constitute an extra risk of retinal tears (P=0.135. Subsequent retinal pathology (follow-up time 4.5 years, including vitreous detachment/hemorrhage or retinal tears/detachment, occurred more often in patients presenting with a retinal tear. For patients with a retinal tear, the relative risk of having a retinal detachment in the same eye during the follow-up time was 17.7 when compared to patients without a retinal tear (risk ratio 17.7, 95% confidence interval 2.2–145. Conclusion: Patients seeking care on the first day have a

  13. Lower Hemoglobin Concentration Is Associated with Retinal Ischemia and the Severity of Diabetic Retinopathy in Type 2 Diabetes.

    Science.gov (United States)

    Traveset, Alicia; Rubinat, Esther; Ortega, Emilio; Alcubierre, Nuria; Vazquez, Beatriz; Hernández, Marta; Jurjo, Carmen; Espinet, Ramon; Ezpeleta, Juan Antonio; Mauricio, Didac

    2016-01-01

    Aims. To assess the association of blood oxygen-transport capacity variables with the prevalence of diabetic retinopathy (DR), retinal ischemia, and macular oedema in patients with type 2 diabetes mellitus (T2DM). Methods. Cross-sectional, case-control study (N = 312) with T2DM: 153 individuals with DR and 159 individuals with no DR. Participants were classified according to the severity of DR and the presence of retinal ischemia or macular oedema. Hematological variables were collected by standardized methods. Three logistic models were adjusted to ascertain the association between hematologic variables with the severity of DR and the presence of retinal ischemia or macular oedema. Results. Individuals with severe DR showed significantly lower hemoglobin, hematocrit, and erythrocyte levels compared with those with mild disease and in individuals with retinal ischemia and macular oedema compared with those without these disorders. Hemoglobin was the only factor that showed a significant inverse association with the severity of DR [beta-coefficient = -0.52, P value = 0.003] and retinal ischemia [beta-coefficient = -0.49, P value = 0.001]. Lower erythrocyte level showed a marginally significant association with macular oedema [beta-coefficient = -0.86, P value = 0.055]. Conclusions. In patients with DR, low blood oxygen-transport capacity was associated with more severe DR and the presence of retinal ischemia. Low hemoglobin levels may have a key role in the development and progression of DR.

  14. Association of the Fractal Dimension of Retinal Arteries and Veins with Quantitative Brain MRI Measures in HIV-Infected and Uninfected Women.

    Directory of Open Access Journals (Sweden)

    Howard A Crystal

    Full Text Available The fractal dimension of retinal arteries and veins is a measure of the complexity of the vascular tree. We hypothesized that retinal fractal dimension would be associated with brain volume and white matter integrity in HIV-infected women.Nested case-control within longitudinal cohort study.Women were recruited from the Brooklyn site of the Women's Interagency HIV study (WIHS; 34 HIV-infected and 21 HIV-uninfected women with analyzable MRIs and retinal photographs were included. Fractal dimension was determined using the SIVA software program on skeletonized retinal images. The relationship between predictors (retinal vascular measures and outcomes (quantitative MRI measures were analyzed with linear regression models. All models included age, intracranial volume, and both arterial and venous fractal dimension. Some models were adjusted for blood pressure, race/ethnicity, and HIV-infection.The women were 45.6 ± 7.3 years of age. Higher arterial dimension was associated with larger cortical volumes, but higher venous dimension was associated with smaller cortical volumes. In fully adjusted models, venous dimension was significantly associated with fractional anisotropy (standardized β = -0.41, p = 0.009 and total gray matter volume (β = -0.24, p = 0.03, and arterial dimension with mean diffusivity (β = -0.33,.p = 0.04 and fractional anisotropy (β = 0.34, p = 0.03. HIV-infection was not associated with any retinal or MRI measure.Higher venous fractal dimension was associated with smaller cortical volumes and lower fractional anisotropy, whereas higher arterial fractal dimension was associated with the opposite patterns. Longitudinal studies are needed to validate this finding.

  15. Association of the Fractal Dimension of Retinal Arteries and Veins with Quantitative Brain MRI Measures in HIV-Infected and Uninfected Women.

    Science.gov (United States)

    Crystal, Howard A; Holman, Susan; Lui, Yvonne W; Baird, Alison E; Yu, Hua; Klein, Ronald; Rojas-Soto, Diana Marcella; Gustafson, Deborah R; Stebbins, Glenn T

    2016-01-01

    The fractal dimension of retinal arteries and veins is a measure of the complexity of the vascular tree. We hypothesized that retinal fractal dimension would be associated with brain volume and white matter integrity in HIV-infected women. Nested case-control within longitudinal cohort study. Women were recruited from the Brooklyn site of the Women's Interagency HIV study (WIHS); 34 HIV-infected and 21 HIV-uninfected women with analyzable MRIs and retinal photographs were included. Fractal dimension was determined using the SIVA software program on skeletonized retinal images. The relationship between predictors (retinal vascular measures) and outcomes (quantitative MRI measures) were analyzed with linear regression models. All models included age, intracranial volume, and both arterial and venous fractal dimension. Some models were adjusted for blood pressure, race/ethnicity, and HIV-infection. The women were 45.6 ± 7.3 years of age. Higher arterial dimension was associated with larger cortical volumes, but higher venous dimension was associated with smaller cortical volumes. In fully adjusted models, venous dimension was significantly associated with fractional anisotropy (standardized β = -0.41, p = 0.009) and total gray matter volume (β = -0.24, p = 0.03), and arterial dimension with mean diffusivity (β = -0.33,.p = 0.04) and fractional anisotropy (β = 0.34, p = 0.03). HIV-infection was not associated with any retinal or MRI measure. Higher venous fractal dimension was associated with smaller cortical volumes and lower fractional anisotropy, whereas higher arterial fractal dimension was associated with the opposite patterns. Longitudinal studies are needed to validate this finding.

  16. Audit on the Efficient Use of Cross-Matched Blood in Elective Total Hip and Total Knee Replacement

    Science.gov (United States)

    Rogers, BA; Johnstone, DJ

    2006-01-01

    INTRODUCTION This prospective audit studies the use of cross-matched blood in 301 patients over a 1-year period undergoing total knee (TKR) and total hip replacement (THR) surgery in an orthopaedic unit. PATIENTS AND METHODS Analysis over the first 6 months revealed a high level of unnecessary cross-matched blood. The following interventions were introduced: (i) to cease routine cross-matching for THR; (ii) all patients to have a check full blood count on day 2 after surgery; and (iii) Hb < 8 g/dl to be considered as the trigger for transfusion in patients over 65 years and free from significant co-morbidity. These changes are in accordance with published national guidelines [Anon. Guidelines for the clinical use of red cell transfusions. Br J Haematol 2001; 113: 24–31]. RESULTS In the next 6 months, the number of units cross-matched but not transfused fell by 96% for THR, and the cross-match transfusion (C:T) ratio reduced from 3.21 to 1.62. Reductions were also observed for the TKR cohort. These results provide evidence of a substantial risk and cost benefit in the use of this limited resource. A telephone survey of 44 hospitals revealed that 20 hospitals routinely cross-matched blood for THR and 11 do so for TKR. CONCLUSIONS Changes can be made to the Maximum Surgical Blood Ordering Schedules (MSBOS) in other orthopaedic units according to national guidelines. PMID:16551419

  17. Chaetomium retinitis.

    Science.gov (United States)

    Tabbara, Khalid F; Wedin, Keith; Al Haddab, Saad

    2010-01-01

    To report a case of Chaetomium atrobrunneum retinitis in a patient with Hodgkin lymphoma. We studied the ocular manifestations of an 11-year-old boy with retinitis. Biomicroscopy, ophthalmoscopy, and fundus photography were done. Magnetic resonance imaging of the brain was performed. A vitreous biopsy was subjected to viral, bacterial, and fungal cultures. Vitreous culture grew C. atrobrunneum. Magnetic resonance imaging showed multiple cerebral lesions consistent with an infectious process. The patient was given intravenous voriconazole and showed improvement of the ocular and central nervous system lesions. We report a case of central nervous system and ocular lesions by C. atrobrunneum. The retinitis was initially misdiagnosed as cytomegaloviral retinitis. Vitreous biopsy helped in the early diagnosis and prompt treatment of a life- and vision-threatening infection.

  18. A confocal scanning laser ophthalmoscope for retinal vessel oximetry

    Science.gov (United States)

    Lompado, Arthur

    Measurement of a person's blood oxygen saturation has long been recognized as a useful metric for the characterizing ailments ranging from chronic respiratory disorders to acute, potentially life threatening, traumas. The ubiquity of oxygen saturation monitors in the medical field, including portable pulse oximeters and laboratory based CO-oximeters, is a testament to the importance of this technique. The work presented here documents the design, fabrication and development of a unique type of oxygen saturation monitor, a confocal scanning retinal vessel oximeter, with the potential to expand the usefulness of the present devices. A large part of the knowledge base required to construct the instrument comes from the consideration of light scattering by red blood cells in a blood vessel. Therefore, a substantial portion of this work is devoted to the process of light scattering by whole human blood and its effects on the development of a more accurate oximeter. This light scattering effect has been both measured and modeled stochastically to determine its contribution to the measured oximeter signal. It is shown that, although well accepted in the published literature, the model only correlates marginally to the measurements due to inherent limitations imposed by the model assumptions. Nonetheless, enough material has been learned about the scattering to allow development of a mathematical model for the interaction of light with blood in a vessel, and this knowledge has been applied to the data reduction of the present oximeter. This data reduction technique has been tested in a controlled experiment employing a model eye with a blood filled mock retinal vessel. It will be shown that the presently developed technique exhibited strong correlation between the known blood oxygen saturation and that calculated by the new system.

  19. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

    DEFF Research Database (Denmark)

    Jørgensen, A; Wiencke, A K; la Cour, M

    1998-01-01

    human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...... induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

  20. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

    DEFF Research Database (Denmark)

    Jørgensen, A; Wiencke, A K; la Cour, M

    1998-01-01

    PURPOSE: The immune privilege of the eye has been thought to be dependent on physical barriers and absence of lymphatic vessels. However, the immune privilege may also involve active immunologic processes, as recent studies have indicated. The purpose of the present study was to investigate whether...... human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...

  1. Combined central retinal artery and vein occlusion in Churg-Strauss syndrome

    DEFF Research Database (Denmark)

    Hamann, Steffen; Johansen, Sven; Hamann, Steffen Ellitsgaard

    2006-01-01

    PURPOSE: To describe a rare case of Churg-Strauss syndrome presenting with severe visual loss due to a combined central retinal vein and artery occlusion. METHODS: A 42-year old man with a medical history of asthma and blood hypereosinophilia developed a sudden loss of vision in his right eye. We...... and dilated and tortuous veins. The diagnosis was confirmed by a fluorescein angiogram showing absence of retinal filling and normal choroidal filling. Churg-Strauss syndrome was diagnosed based on the necessary presence of four of six criteria for the disease proposed by the American College of Rheumatology...... the vascular occlusion and experienced no visual improvement. CONCLUSION: Combined central retinal artery and vein occlusion can occur in Churg-Strauss syndrome. We suggest that regional vasculitis may be the pathological mechanism underlying the vascular occlusions observed in our case. The condition carries...

  2. Tranexamic acid versus aminocaproic acid for blood management after total knee and total hip arthroplasty: A systematic review and meta-analysis.

    Science.gov (United States)

    Liu, Qiuliang; Geng, Peishuo; Shi, Longyan; Wang, Qi; Wang, Pengliang

    2018-06-01

    To compare the efficacy and safety of tranexamic acid and aminocaproic acid for reducing blood loss and transfusion requirements after total knee and total hip arthroplasty. We conduct electronic searches of Medline (1966-2017.11), PubMed (1966-2017.11), Embase (1980-2017.11), ScienceDirect (1985-2017.11) and the Cochrane Library (1900-2017.11). The primary outcomes, including total blood loss, hemoglobin decline and transfusion requirements. Secondary outcomes include length of hospital stay and postoperative complications such as the incidence of deep vein thrombosis and pulmonary embolism. Each outcome is combined and calculated using the statistical software STATA 12.0. Fixed/random effect model is adopted based on the heterogeneity tested by I 2 statistic. A total of 1714 patients are analyzed across three randomized controlled trials (RCTs) and one non-RCT. The present meta-analysis reveals that TXA is associated with a significantly reduction of total blood loss and postoperative hemoglobin drop compared with EACA. No significant differences are identified in terms of transfusion rates, length of hospital stay, and the incidence of postoperative complications. Although total blood loss and postoperative hemoglobin drop are significant greater in EACA groups, there is no significant difference between TXA and EACA groups in terms of transfusion rates. Based on the current evidence available, higher quality RCTs are still required for further research. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  3. High glucose alters retinal astrocytes phenotype through increased production of inflammatory cytokines and oxidative stress.

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    Full Text Available Astrocytes are macroglial cells that have a crucial role in development of the retinal vasculature and maintenance of the blood-retina-barrier (BRB. Diabetes affects the physiology and function of retinal vascular cells including astrocytes (AC leading to breakdown of BRB. However, the detailed cellular mechanisms leading to retinal AC dysfunction under high glucose conditions remain unclear. Here we show that high glucose conditions did not induce the apoptosis of retinal AC, but instead increased their rate of DNA synthesis and adhesion to extracellular matrix proteins. These alterations were associated with changes in intracellular signaling pathways involved in cell survival, migration and proliferation. High glucose conditions also affected the expression of inflammatory cytokines in retinal AC, activated NF-κB, and prevented their network formation on Matrigel. In addition, we showed that the attenuation of retinal AC migration under high glucose conditions, and capillary morphogenesis of retinal endothelial cells on Matrigel, was mediated through increased oxidative stress. Antioxidant proteins including heme oxygenase-1 and peroxiredoxin-2 levels were also increased in retinal AC under high glucose conditions through nuclear localization of transcription factor nuclear factor-erythroid 2-related factor-2. Together our results demonstrated that high glucose conditions alter the function of retinal AC by increased production of inflammatory cytokines and oxidative stress with significant impact on their proliferation, adhesion, and migration.

  4. Tranexamic Acid Reduced the Percent of Total Blood Volume Lost During Adolescent Idiopathic Scoliosis Surgery.

    Science.gov (United States)

    Jones, Kristen E; Butler, Elissa K; Barrack, Tara; Ledonio, Charles T; Forte, Mary L; Cohn, Claudia S; Polly, David W

    2017-01-01

    Multilevel posterior spine fusion is associated with significant intraoperative blood loss. Tranexamic acid is an antifibrinolytic agent that reduces intraoperative blood loss. The goal of this study was to compare the percent of total blood volume lost during posterior spinal fusion (PSF) with or without tranexamic acid in patients with adolescent idiopathic scoliosis (AIS). Thirty-six AIS patients underwent PSF in 2011-2014; the last half (n=18) received intraoperative tranexamic acid. We retrieved relevant demographic, hematologic, intraoperative and outcomes information from medical records. The primary outcome was the percent of total blood volume lost, calculated from estimates of intraoperative blood loss (numerator) and estimated total blood volume per patient (denominator, via Nadler's equations). Unadjusted outcomes were compared using standard statistical tests. Tranexamic acid and no-tranexamic acid groups were similar (all p>0.05) in mean age (16.1 vs. 15.2 years), sex (89% vs. 83% female), body mass index (22.2 vs. 20.2 kg/m2), preoperative hemoglobin (13.9 vs. 13.9 g/dl), mean spinal levels fused (10.5 vs. 9.6), osteotomies (1.6 vs. 0.9) and operative duration (6.1 hours, both). The percent of total blood volume lost (TBVL) was significantly lower in the tranexamic acid-treated vs. no-tranexamic acid group (median 8.23% vs. 14.30%, p = 0.032); percent TBVL per level fused was significantly lower with tranexamic acid than without it (1.1% vs. 1.8%, p=0.048). Estimated blood loss (milliliters) was similar across groups. Tranexamic acid significantly reduced the percentage of total blood volume lost versus no tranexamic acid in AIS patients who underwent PSF using a standardized blood loss measure.Level of Evidence: 3. Institutional Review Board status: This medical record chart review (minimal risk) study was approved by the University of Minnesota Institutional Review Board.

  5. Application of Arterial Spin Labelling in Detecting Retinal Ischemia

    Directory of Open Access Journals (Sweden)

    Ehsan Vaghefi

    2017-12-01

    Full Text Available Purpose: Here, we have tried to quantify the chorioretinal blood perfusion in patients who are clinically identified to be suffering from retinal ischemia using arterial spin labelling (ASL MRI. Method: Four participants, diagnosed with retinal ischemia based on their structural OCT and angiography test, were then scanned using anatomical MRI as well as ASL. We optimized MR parameters to maximize resolution and target fixation, blinking, and breathing ques to minimize motion artifacts. Results: Participants had a maximum of ∼50 mL/100 mL/min of blood perfusion, which is below the normal values of ∼200 mL/100 mL/min. It also appeared that thinning of the choroid contributes more to the measured decreased chorioretinal perfusion, compared to slowed arterial filling time. Conclusion: Decreased chorioretinal perfusion is a multifactorial event and has been implicated in several posterior eye pathologies. Based on our current results, it seems that ischemia of the eye could be due to anatomy (tissue volume and/or functionality (arterial flow.

  6. Novel Computerized Method for Measurement of Retinal Vessel Diameters

    Directory of Open Access Journals (Sweden)

    Hichem Guedri

    2017-03-01

    Full Text Available Several clinical studies reveal the relationship between alterations in the topologies of the human retinal blood vessel, the outcrop and the disease evolution, such as diabetic retinopathy, hypertensive retinopathy, and macular degeneration. Indeed, the detection of these vascular changes always has gaps. In addition, the manual steps are slow, which may be subjected to a bias of the perceiver. However, we can overcome these troubles using computer algorithms that are quicker and more accurate. This paper presents and investigates a novel method for measuring the blood vessel diameter in the retinal image. The proposed method is based on a thresholding segmentation and thinning step, followed by the characteristic point determination step by the Douglas-Peucker algorithm. Thereafter, it uses the active contours to detect vessel contour. Finally, Heron’s Formula is applied to assure the calculation of vessel diameter. The obtained results for six sample images showed that the proposed method generated less errors compared to other techniques, which confirms the high performance of the proposed method.

  7. Evidence of Flicker-Induced Functional Hyperaemia in the Smallest Vessels of the Human Retinal Blood Supply.

    Directory of Open Access Journals (Sweden)

    Angelina Duan

    Full Text Available Regional changes in blood flow are initiated within neural tissue to help fuel local differences in neural activity. Classically, this response was thought to arise only in larger arterioles and venules. However, recently, it has been proposed that a the smallest vessels of the circulation make a comparable contribution, and b the response should be localised intermittently along such vessels, due to the known distribution of contractile mural cells. To assess these hypotheses in human neural tissue in vivo, we imaged the retinal microvasculature (diameters 3-28 μm non-invasively, using adaptive optics, before and after delivery of focal (360 μm patches of flickering visible light. Our results demonstrated a definite average response in 35% of all vessel segments analysed. In these responding vessels, the magnitude of proportional dilation (mean ± SEM for pre-capillary arterioles 13 ± 5%, capillaries 31 ± 8%, and post-capillary venules 10 ± 3% is generally far greater than the magnitudes we and others have measured in the larger retinal vessels, supporting proposition a above. The dilations observed in venules were unexpected based on previous animal work, and may be attributed either to differences in stimulus or species. Response heterogeneity across the network was high; responses were also heterogeneous along individual vessels (45% of vessel segments showed demonstrable locality in their response. These observations support proposition b above. We also observed a definite average constriction across 7% of vessel segments (mean ± SEM constriction for capillaries -16 ± 3.2%, and post-capillary venules -18 ± 12%, which paints a picture of dynamic redistribution of flow throughout the smallest vessel networks in the retina in response to local, stimulus-driven metabolic demand.

  8. LONG-TERM OUTCOMES OF RETINAL DEGENERATIVE DISORDER TREATMENT WITH PEPTIDE BIOREGULATORS

    Directory of Open Access Journals (Sweden)

    M. I. Razumovskiy

    2015-01-01

    Full Text Available Aim. To analyze long-term outcomes and efficacy of retinal degeneration treatment with Retinalamin.Patients and methods. Group I included 20 patients (40 eyes with pigmentary retinal dystrophy (15 patients, 30 eyes and retinal abiotrophy (5 patients, 10 eyes who received treatment with Retinalamin for 5‑7 years. Group II included 11 patients (22 eyes with pigmentary retinal dystrophy (9 patients, 18 eyes and retinal abiotrophy (2 patients, 4 eyes who received treatment with Retinalamin for 23‑25 years. Group III (controls included 15 patients (30 eyes with pigmentary retinal dystrophy (11 patients, 22 eyes and retinal abiotrophy (4 patients, 8 eyes who received traditional treatment (vasodilators, angioprotectors, antisclerotic agents, vitamins for 25 years. Standard ophthalmological examination, i.e., visual acuity measurement, visual field test, refractometry, biomicroscopy, ophthalmoscopy, was performed.Results. First course of treatment with Retinalamin improved vision in 58.1 % of retinal degeneration patients. Visual fields improved in 64.5 % of cases. Repeated treatment courses (1‑2 times a year for 23‑25 years preserved residual vision in 55.6 % of patients and object vision in 11.1 % of cases. In retinal abiotrophy patients, residual vision preserved in 100 % of cases.Conclusions. In retinal degenerations, Retinalamin improves vision and visual fields and decreases total area of absolute scotomas even after the first treatment course as well as preserves vision in prolonged use. 

  9. Supervised retinal vessel segmentation from color fundus images based on matched filtering and AdaBoost classifier.

    Directory of Open Access Journals (Sweden)

    Nogol Memari

    Full Text Available The structure and appearance of the blood vessel network in retinal fundus images is an essential part of diagnosing various problems associated with the eyes, such as diabetes and hypertension. In this paper, an automatic retinal vessel segmentation method utilizing matched filter techniques coupled with an AdaBoost classifier is proposed. The fundus image is enhanced using morphological operations, the contrast is increased using contrast limited adaptive histogram equalization (CLAHE method and the inhomogeneity is corrected using Retinex approach. Then, the blood vessels are enhanced using a combination of B-COSFIRE and Frangi matched filters. From this preprocessed image, different statistical features are computed on a pixel-wise basis and used in an AdaBoost classifier to extract the blood vessel network inside the image. Finally, the segmented images are postprocessed to remove the misclassified pixels and regions. The proposed method was validated using publicly accessible Digital Retinal Images for Vessel Extraction (DRIVE, Structured Analysis of the Retina (STARE and Child Heart and Health Study in England (CHASE_DB1 datasets commonly used for determining the accuracy of retinal vessel segmentation methods. The accuracy of the proposed segmentation method was comparable to other state of the art methods while being very close to the manual segmentation provided by the second human observer with an average accuracy of 0.972, 0.951 and 0.948 in DRIVE, STARE and CHASE_DB1 datasets, respectively.

  10. Quantification of total hexose on dry blood spot by tandem mass spectrometry.

    Science.gov (United States)

    Gong, Zhenhua; Tian, Guoli; Huang, Qiwei; Wang, Yanmin; Ge, Qingwei

    2012-12-01

    Because hypoglycemia and hyperglycemia are harmful and not always associated with overt clinical signs, it is necessary to have methods available to screen for glucose levels to detect hypoglycemia and diabetes as early as possible. A new method for such screening and the clinical determination of blood total hexose on a dry blood spot (DBS) using tandem mass spectrometry (MS/MS) was developed. The serum glucose controls and blood were prepared as DBS and then extracted into a methanol solution containing isotope-labeled internal standards. The methanolic extraction was subjected to HPLC, followed by MS/MS in positive ion mode. Multiple-reaction monitoring of m/z 203.1→23 was used to detect hexose, and m/z 209.0→23 was used for 13C6-D-glucose. The recoveries of blood glucose by MS/MS were 90%-102% with an R(2) value of 0.999 after linear regression (pblood total hexose in neonates aged 3-7 days (6.41±1.46 mmol/L) was lower than that in neonates aged 8-30 days (6.66±1.38 mmol/L), and it was lower in neonates than in children aged 1-72 months (7.19±1.87 mmol/L). Quantification of total hexose on a dry blood spot by MS/MS is accurate, reliable and feasible for screening and clinical tests. Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  11. Retinitis Pigmentosa.

    Science.gov (United States)

    Carr, Ronald E.

    1979-01-01

    The author describes the etiology of retinitis pigmentosa, a visual dysfunction which results from progressive loss of the retinal photoreceptors. Sections address signs and symptoms, ancillary findings, heredity, clinical diagnosis, therapy, and research. (SBH)

  12. Ciclosporine A asxay: RIA or HPLC, plasma or total blood

    International Nuclear Information System (INIS)

    Lapalus, P.; Garraffo, R.; Krebs, B.; Lapalus, F.

    1985-01-01

    The two methods now in force for ciclosporine A assay are radioimmunoassay (RIA) and high pressure liquid chromatography (HPLC) in various biological media (plasma, serum, total blood). The advantages and disadvantages of the two methods are presented [fr

  13. Retinal Layer Abnormalities as Biomarkers of Schizophrenia.

    Science.gov (United States)

    Samani, Niraj N; Proudlock, Frank A; Siram, Vasantha; Suraweera, Chathurie; Hutchinson, Claire; Nelson, Christopher P; Al-Uzri, Mohammed; Gottlob, Irene

    2018-06-06

    Schizophrenia is associated with several brain deficits, as well as visual processing deficits, but clinically useful biomarkers are elusive. We hypothesized that retinal layer changes, noninvasively visualized using spectral-domain optical coherence tomography (SD-OCT), may represent a possible "window" to these abnormalities. A Leica EnvisuTM SD-OCT device was used to obtain high-resolution central foveal B-scans in both eyes of 35 patients with schizophrenia and 50 demographically matched controls. Manual retinal layer segmentation was performed to acquire individual and combined layer thickness measurements in 3 macular regions. Contrast sensitivity was measured at 3 spatial frequencies in a subgroup of each cohort. Differences were compared using adjusted linear models and significantly different layer measures in patients underwent Spearman Rank correlations with contrast sensitivity, quantified symptoms severity, disease duration, and antipsychotic medication dose. Total retinal and photoreceptor complex thickness was reduced in all regions in patients (P layer (P layer (P layer thickness (R = -.47, P = .005). Our novel findings demonstrate considerable retinal layer abnormalities in schizophrenia that are related to clinical features and visual function. With time, SD-OCT could provide easily-measurable biomarkers to facilitate clinical assessment and further our understanding of the disease.

  14. Retinitis Pigmentosa

    Science.gov (United States)

    ... Linked Retinoschisis (XLRS) X-Linked Retinitis Pigmentosa (XLRP) Usher Syndrome Other Retinal Diseases Glossary News & Research News & Research ... degenerate. Forms of RP and related diseases include Usher syndrome, Leber congenital amaurosis, and Bardet-Biedl syndrome, among ...

  15. Retinal Diseases

    Science.gov (United States)

    ... Linked Retinoschisis (XLRS) X-Linked Retinitis Pigmentosa (XLRP) Usher Syndrome Other Retinal Diseases Glossary News & Research News & Research ... central portion of the retina called the macula. Usher Syndrome Usher syndrome is an inherited condition characterized by ...

  16. Acute normovolaemic haemodilution decreases postoperative allogeneic blood transfusion after total knee replacement.

    Science.gov (United States)

    Olsfanger, D; Fredman, B; Goldstein, B; Shapiro, A; Jedeikin, R

    1997-09-01

    We hypothesized that the success of postoperative blood conservation after acute normovolaemic haemodilution (NVHD) is influenced by the extent of intraoperative bleeding and surgical trauma, and the timing of autologous blood transfusion. As total knee replacement is associated with minimal intraoperative but extensive postoperative blood loss, this procedure is ideally suited to acute NVHD. Therefore, to test our hypothesis, 30 patients undergoing elective total knee replacement were enrolled in a prospective, randomized, controlled study. In groups NVHD-2 and NVHD-6, before induction of anaesthesia patients were bled to a target packed cell volume (PCV) of 28-30%, and in the post-anaesthesia care unit autologous blood was transfused over a 2-h period terminating after operation at 2 and 6 h, respectively. In the control group, NVHD was not performed. After operation, platelets, fibrinogen, prothrombin and partial thromboplastin time, and liver function, urea and electrolytes were measured and compared with preoperative baseline values. Significantly (P conservation strategy. However, there was no difference in allogeneic blood administration between the two NVHD groups. Coagulation and liver function, and urea and electrolyte concentrations were unaffected by treatment.

  17. Loss of Melanopsin-Expressing Retinal Ganglion Cells in Patients With Diabetic Retinopathy

    DEFF Research Database (Denmark)

    Obara, Elisabeth Anne; Hannibal, Jens; Heegaard, Steffen

    2017-01-01

    Purpose: Photo-entrainment of the circadian clock is mediated by melanopsin-expressing retinal ganglion cells (mRGCs) located in the retina. Patients suffering from diabetic retinopathy (DR) show impairment of light regulated circadian activity such as sleep disorders, altered blood pressure...

  18. Detection of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa)

    Science.gov (United States)

    Ekawati, ER; Yusmiati, S. N. H.

    2018-01-01

    Blood cockle (Anadara granosa) has high level of zinc and protein, which is beneficial for therapeutic function for malnourished particularly stunting case in children. Zinc in animal foods is more absorbable than that from vegetable food. Blood cockle (Anadara granosa) is rich in nutrient and an excellent environment for the growth of microorganisms. This research aimed to identify the contamination of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa). This was observation research with laboratory analysis. Salmonella sp. and Vibrio sp. were detected from blood cockle. Total plate count was determine of the total amount of the bacteria. Results detected from 20 samples of blood cockle showed that all samples were negative of Salmonella sp. and 1 sample positive Vibrio sp. The result of total plate count bacteria was < 5 x 105 colony/g sample.

  19. Transplanting Retinal Cells using Bucky Paper for Support

    Science.gov (United States)

    Loftus, David J.; Cinke, Martin; Meyyappan, Meyya; Fishman, Harvey; Leng, Ted; Huie, Philip; Bilbao, Kalayaan

    2004-01-01

    A novel treatment for retinal degenerative disorders involving transplantation of cells into the eye is currently under development at NASA Ames Research Center and Stanford University School of Medicine. The technique uses bucky paper as a support material for retinal pigment epithelial (RPE) cells, iris pigment epithelial (IPE) cells, and/or stem cells. This technology is envisioned as a treatment for age-related macular degeneration, which is the leading cause of blindness in persons over age 65 in Western nations. Additionally, patients with other retinal degenerative disorders, such as retinitis pigmentosa, may be treated by this strategy. Bucky paper is a mesh of carbon nanotubes (CNTs), as shown in Figure 1, that can be made from any of the commercial sources of CNTs. Bucky paper is biocompatible and capable of supporting the growth of biological cells. Because bucky paper is highly porous, nutrients, oxygen, carbon dioxide, and waste can readily diffuse through it. The thickness, density, and porosity of bucky paper can be tailored in manufacturing. For transplantation of cells into the retina, bucky paper serves simultaneously as a substrate for cell growth and as a barrier for new blood vessel formation, which can be a problem in the exudative type of macular degeneration. Bucky paper is easily handled during surgical implantation into the eye. Through appropriate choice of manufacturing processes, bucky paper can be made relatively rigid yet able to conform to the retina when the bucky paper is implanted. Bucky paper offers a distinct advantage over other materials that have been investigated for retinal cell transplantation - lens capsule and Descemet's membrane - which are difficult to handle during surgery because they are flimsy and do not stay flat.

  20. Ocular blood flow decreases during passive heat stress in resting humans.

    Science.gov (United States)

    Ikemura, Tsukasa; Miyaji, Akane; Kashima, Hideaki; Yamaguchi, Yuji; Hayashi, Naoyuki

    2013-12-06

    Heat stress induces various physiological changes and so could influence ocular circulation. This study examined the effect of heat stress on ocular blood flow. Ocular blood flow, end-tidal carbon dioxide (P(ET)CO2) and blood pressure were measured for 12 healthy subjects wearing water-perfused tube-lined suits under two conditions of water circulation: (1) at 35 °C (normothermia) for 30 min and (2) at 50 °C for 90 min (passive heat stress). The blood-flow velocities in the superior temporal retinal arteriole (STRA), superior nasal retinal arteriole (SNRA), and the retinal and choroidal vessels (RCV) were measured using laser-speckle flowgraphy. Blood flow in the STRA and SNRA was calculated from the integral of a cross-sectional map of blood velocity. PETCO2 was clamped at the normothermia level by adding 5% CO2 to the inspired gas. Passive heat stress had no effect on the subjects' blood pressures. The blood-flow velocity in the RCV was significantly lower after 30, 60 and 90 min of passive heat stress than the normothermic level, with a peak decrease of 18 ± 3% (mean ± SE) at 90 min. Blood flow in the STRA and SNRA decreased significantly after 90 min of passive heat stress conditions, with peak decreases of 14 ± 3% and 14 ± 4%, respectively. The findings of this study suggest that passive heat stress decreases ocular blood flow irrespective of the blood pressure or arterial partial pressure of CO2.

  1. Lower Hemoglobin Concentration Is Associated with Retinal Ischemia and the Severity of Diabetic Retinopathy in Type 2 Diabetes

    Science.gov (United States)

    Traveset, Alicia; Rubinat, Esther; Ortega, Emilio; Alcubierre, Nuria; Vazquez, Beatriz; Hernández, Marta; Jurjo, Carmen; Espinet, Ramon; Ezpeleta, Juan Antonio; Mauricio, Didac

    2016-01-01

    Aims. To assess the association of blood oxygen-transport capacity variables with the prevalence of diabetic retinopathy (DR), retinal ischemia, and macular oedema in patients with type 2 diabetes mellitus (T2DM). Methods. Cross-sectional, case-control study (N = 312) with T2DM: 153 individuals with DR and 159 individuals with no DR. Participants were classified according to the severity of DR and the presence of retinal ischemia or macular oedema. Hematological variables were collected by standardized methods. Three logistic models were adjusted to ascertain the association between hematologic variables with the severity of DR and the presence of retinal ischemia or macular oedema. Results. Individuals with severe DR showed significantly lower hemoglobin, hematocrit, and erythrocyte levels compared with those with mild disease and in individuals with retinal ischemia and macular oedema compared with those without these disorders. Hemoglobin was the only factor that showed a significant inverse association with the severity of DR [beta-coefficient = −0.52, P value = 0.003] and retinal ischemia [beta-coefficient = −0.49, P value = 0.001]. Lower erythrocyte level showed a marginally significant association with macular oedema [beta-coefficient = −0.86, P value = 0.055]. Conclusions. In patients with DR, low blood oxygen-transport capacity was associated with more severe DR and the presence of retinal ischemia. Low hemoglobin levels may have a key role in the development and progression of DR. PMID:27200379

  2. Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

    Science.gov (United States)

    Park, Susanna S

    2016-04-01

    Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

  3. Intraretinal hyperreflective foci on spectral-domain optical coherence tomographic images of patients with retinitis pigmentosa

    Science.gov (United States)

    Kuroda, Masako; Hirami, Yasuhiko; Hata, Masayuki; Mandai, Michiko; Takahashi, Masayo; Kurimoto, Yasuo

    2014-01-01

    Background The purpose of this study was to observe the characteristic findings of spectral-domain optical coherence tomography (SD-OCT) images in the retinas of patients with retinitis pigmentosa and to evaluate their distribution patterns in the early and advanced stages of the disease. Methods A total of 184 patients (368 eyes) with retinitis pigmentosa were observed using SD-OCT. We studied the presence or absence of continuous inner/outer segment (IS/OS) lines, presence of thinning of the retinal pigment epithelium-Bruch’s membrane complex, and distribution patterns of hyperreflective foci in the inner and outer nuclear layers (INL and ONL). Results The IS/OS junction had partially disappeared in 275 eyes, which were at the early stage of retinitis pigmentosa (group X), whereas the junction had totally disappeared in 93, which were at the advanced stage of retinitis pigmentosa (group Y). Hyperreflective foci in the INL were observed in a significantly larger proportion of the eyes in group X than in group Y (90% versus 61%, Pretinitis pigmentosa and hyperreflective foci in the ONL were more frequently observed in the advanced stage. Hyperreflective foci may be indicative of changes in the retinal structure at each stage of retinitis pigmentosa. PMID:24591813

  4. An Evaluation of Intra‑ and Post‑operative Blood Loss in Total Hip ...

    African Journals Online (AJOL)

    2017-05-18

    May 18, 2017 ... Results: The mean intra‑ and post‑operative blood losses were 1222.7 ... To evaluate blood loss after total hip replacement. 2. To evaluate the .... 12.3. 4.2. 0.1. Median. 400.0. 150.0. 20.0. 3.0. Mode. 400.0. 100.0. 0.0. 3.0. SD.

  5. Investigation of the Protective Effects of Taurine against Alloxan-Induced Diabetic Retinal Changes via Electroretinogram and Retinal Histology with New Zealand White Rabbits

    Directory of Open Access Journals (Sweden)

    Samuel Tung-Hsing Chiang

    2014-01-01

    Full Text Available The purpose of this study was to investigate the protective role of orally administered taurine against diabetic retinal changes via electroretinogram (ERG and retinal histology on rabbits. Rabbits were randomly assigned into groups: Group I (vehicle administration only; Group II (diabetes: induced by 100 mg/kg alloxan injection; Group III (diabetes and fed with 200 mg/kg taurine; and Group IV (diabetes and fed with 400 mg/kg taurine. The body weight and blood glucose levels of the rabbits were monitored weekly. The ERG was measured on weeks 5 and 15. Retinal histology was analyzed in the end of the experiment. Results revealed that a taurine supplement significantly ameliorates the alloxan-induced hyperglycemia and protects the retina from electrophysiological changes. Group II showed a significant (P0.05 between all groups and when compared with those of Group I. Our study provides solid evidences that taurine possesses an antidiabetic activity, reduced loss of body weight, and less electrophysiological changes of the diabetic retina.

  6. Dynamic association between intraocular pressure and spontaneous pulsations of retinal veins.

    Science.gov (United States)

    Golzan, S Mojtaba; Graham, Stuart L; Leaney, John; Avolio, Alberto

    2011-01-01

    The amplitude of spontaneous retinal venous pulsations (SRVP) is known to be affected by intraocular pressure (IOP), retinal venous pressure, and intracranial pressure (ICP). This study characterized SRVPs adjacent to the disc and quantified changes in the amplitude of these pulsations during IOP manipulation in normal subjects. The study included 12 subjects (40 ± 15, 4 females, 8 males). Baseline IOP (range 10-25 mmHg) was measured and SRVP recorded using the dynamic retinal vessel analyzer (DVA). IOP was lowered using aproclonidine 0.5% and measured every 15 min, followed by dynamic recording of SRVP. Two subjects were also tested with timolol 0.5%, and three were treated with a placebo drop. Mean amplitude of SRVP was determined within each sample at the same site. Blood pressure and heart rate were tracked continuously. Amplitude of SRVP decreased in all subjects with reduction of IOP with aproclonidine and timolol. Mean SRVP amplitude was 8.5 ± 6 μm at baseline and reduced to 2.5 ± 1.8 μm after 45 min (p blood pressure, and heart rate did not change significantly from the baseline. Analysis of waveforms showed a slight phase shift only (150 ± 78.5 ms, p = 0.93) between disc veins and adjacent retinal vein. SRVPs in the peripapillary retina have similar waveform characteristics to those at the disc. SRVP amplitudes are reduced by manipulation of IOP downwards with pharmacological intervention. The relationship was consistent in all individuals tested for two classes of drugs and was independent of BP or heart rate changes.

  7. A new strategy for umbilical cord blood collection developed at the first Colombian public cord blood bank increases total nucleated cell content.

    Science.gov (United States)

    Vanegas, Diana; Triviño, Lady; Galindo, Cristian; Franco, Leidy; Salguero, Gustavo; Camacho, Bernardo; Perdomo-Arciniegas, Ana-María

    2017-09-01

    The total nucleated cell dosage of umbilical cord blood (UCB) is an important factor in determining successful allogeneic hematopoietic stem cell transplantation after a minimum human leukocyte antigen donor-recipient match. The northern South American population is in need of a new-generation cord blood bank that cryopreserves only units with high total nucleated cell content, thereby increasing the likelihood of use. Colombia set up a public cord blood bank in 2014; and, as a result of its research for improving high total nucleated cell content, a new strategy for UCB collection was developed. Data from 2933 collected and 759 cryopreserved cord blood units between 2014 and 2015 were analyzed. The correlation of donor and collection variables with cellularity was evaluated. Moreover, blood volume, cell content, CD34+ count, clonogenic capacity, and microbial contamination were assessed comparing the new method, which combines in utero and ex utero techniques, with the conventional strategies. Multivariate analysis confirmed a correlation between neonatal birth weight and cell content. The new collection method increased total nucleated cell content in approximately 26% and did not alter pre-cryopreservation and post-thaw cell recovery, viability, or clonogenic ability. Furthermore, it showed a remarkably low microbial contamination rate (1.2%). The strategy for UCB collection developed at the first Colombian public cord blood bank increases total nucleated cell content and does not affect unit quality. The existence of this bank is a remarkable breakthrough for Latin-American patients in need of this kind of transplantation. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  8. Neovascular Glaucoma Induced by Peripheral Retinal Ischemia in Neurofibromatosis Type 1: Management and Imaging Features

    Directory of Open Access Journals (Sweden)

    Francesco Pichi

    2013-04-01

    Full Text Available Purpose: To report the case of a young patient affected by neurofibromatosis 1 (NF-1 with peripheral retinal ischemia-induced neovascular glaucoma and the peculiar spectral-domain optical coherence tomography (SD-OCT features. Material and Methods: A 13-year-old boy affected by NF-1, as diagnosed according to established criteria, was referred with a diagnosis of hypertensive uveitis in his left eye. He underwent a complete ophthalmic examination and comprehensive blood work with viral and immunological tests. The case was documented with fluorescein angiography (FA and SD-OCT. When the intraocular pressure (IOP of the left eye decreased and the cornea cleared, FA revealed retinal ischemia and leakage from pathologic retinal vessels. SD-OCT revealed foveal hypoplasia secondary to the complete absence of the retinal nerve fiber layer. Results: Peripheral retinal ischemia-induced neovascular glaucoma was diagnosed. The patient underwent Ahmed valve implantation to control his IOP, and subsequent retinal photocoagulation by argon laser and intravitreal bevacizumab injection were performed to control neovascularization. Discussion: Retinal ischemia in NF-1 might lead to neovascular glaucoma: lowering of the IOP with surgical implantation of an Ahmed valve, regression of neovascularization by argon laser panretinal photocoagulation and intravitreal injection of bevacizumab can be a helpful way to control such a complication.

  9. Optical coherence tomography study of retinal changes in normal aging and after ischemia.

    Science.gov (United States)

    Shariati, Mohammad Ali; Park, Joyce Ho; Liao, Yaping Joyce

    2015-05-01

    Age-related thinning of the retinal ganglion cell axons in the nerve fiber layer has been measured in humans using optical coherence tomography (OCT). In this study, we used OCT to measure inner retinal changes in 3-month-, 1-year-, and 2-year-old mice and after experimental anterior ischemic optic neuropathy (AION). We used OCT to quantify retinal thickness in over 200 eyes at different ages before and after a photochemical thrombosis model of AION. The scans were manually or automatically segmented. In normal aging, there was 1.3-μm thinning of the ganglion cell complex (GCC) between 3 months and 1 year (P < 0.0001) and no further thinning at 2 years. In studying age-related inner retinal changes, measurement of the GCC (circular scan) was superior to that of the total retinal thickness (posterior pole scan) despite the need for manual segmentation because it was not contaminated by outer retinal changes. Three weeks after AION, there was 8.9-μm thinning of the GCC (circular scan; P < 0.0001), 50-μm thinning of the optic disc (posterior pole scan; P < 0.0001), and 17-μm thinning of the retina (posterior pole scan; P < 0.0001) in the 3-month-old group. Changes in the older eyes after AION were similar to those of the 3-month-old group. Optical coherence tomography imaging of a large number of eyes showed that, like humans, mice exhibited small, age-related inner retinal thinning. Measurement of the GCC was superior to total retinal thickness in quantifying age-related changes, and both circular and posterior pole scans were useful to track short-term changes after AION.

  10. Retinal Vascular Fractals and Microvascular and Macrovascular Complications in Type 1 Diabetes

    DEFF Research Database (Denmark)

    Grauslund, Jakob; Green, Anders; Kawasaki, Ryo

    2010-01-01

    diabetes. DESIGN: Cross-sectional study. PARTICIPANTS: This was a cross-sectional study of 208 long-term surviving type 1 diabetes patients from a population-based Danish cohort identified in 1973. METHODS: Retinal photographs were obtained at a clinical examination in 2007 or 2008. D(f) was measured......, respectively. Median D(f) was 1.4610 (range, 1.3774-1.5188). After adjustments for age, gender, duration of diabetes, systolic blood pressure, and smoking, persons with lower D(f) were more likely to have proliferative retinopathy (odds ratio [OR], 1.45 per standard deviation [SD] decrease in D(f); 95......PURPOSE: Fractal analysis is a method to quantify the geometric pattern and complexity of the retinal vessels. This study examined the association of retinal fractal dimension (D(f)) and microvascular and macrovascular complications in a population-based cohort of Danish patients with type 1...

  11. Retinal Endovascular Surgery with Tissue Plasminogen Activator Injection for Central Retinal Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Yuta Takata

    2018-06-01

    Full Text Available Purpose: To report 2 cases of central retinal artery occlusion (CRAO who underwent retinal endovascular surgery with injection of tissue plasminogen activator (tPA into the retinal artery and showed a remarkable improvement in visual acuity and retinal circulation. Methods: Standard 25-G vitrectomy was performed under local anesthesia. Simultaneously, tPA (80,000 units/mL solution was injected into the retinal artery of the optic disc for 2–3 min using a microneedle. Changes in visual acuity, fundus photography, optical coherence tomography (OCT, fluorescein angiography, and laser speckle flowgraphy (LSFG results were examined. Results: Both cases could be treated within 12 h after the onset of CRAO. Case 1 was a 47-year-old woman. Her visual acuity improved from counting fingers before operation to 0.08 logMAR 1 month after the surgery. However, thinning of the retina at the macula was observed by OCT. Case 2 was a 70-year-old man. His visual acuity improved from counting fingers to 0.1 logMAR 2 months after the surgery. Both fluorescein angiography and LSFG showed improvement in retinal circulation after the surgery in case 2. Conclusions: Retinal endovascular surgery with injection of tPA into the retinal artery was feasible and may be a way to improve visual acuity and retinal circulation when performed in the acute phase of CRAO.

  12. 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.

  13. Retinitis pigmentosa-associated cystoid macular oedema: pathogenesis and avenues of intervention

    Science.gov (United States)

    Strong, S; Liew, G; Michaelides, M

    2017-01-01

    Hereditary retinal diseases are now the leading cause of blindness certification in the working age population (age 16–64 years) in England and Wales, of which retinitis pigmentosa (RP) is the most common disorder. RP may be complicated by cystoid macular oedema (CMO), causing a reduction of central vision. The underlying pathogenesis of RP-associated CMO (RP-CMO) remains uncertain, however, several mechanisms have been proposed, including: (1) breakdown of the blood-retinal barrier, (2) failure (or dysfunction) of the pumping mechanism in the retinal pigment epithelial, (3) Müller cell oedema and dysfunction, (4) antiretinal antibodies and (5) vitreous traction. There are limited data on efficacy of treatments for RP-CMO. Treatments attempted to date include oral and topical carbonic anhydrase inhibitors, oral, topical, intravitreal and periocular steroids, topical non-steroidal anti-inflammatory medications, photocoagulation, vitrectomy with internal limiting membrane peel, oral lutein and intravitreal antivascular endothelial growth factor injections. This review summarises the evidence supporting these treatment modalities. Successful management of RP-CMO should aim to improve both quality and quantity of vision in the short term and may also slow central vision loss over time. PMID:27913439

  14. Multi-level deep supervised networks for retinal vessel segmentation.

    Science.gov (United States)

    Mo, Juan; Zhang, Lei

    2017-12-01

    Changes in the appearance of retinal blood vessels are an important indicator for various ophthalmologic and cardiovascular diseases, including diabetes, hypertension, arteriosclerosis, and choroidal neovascularization. Vessel segmentation from retinal images is very challenging because of low blood vessel contrast, intricate vessel topology, and the presence of pathologies such as microaneurysms and hemorrhages. To overcome these challenges, we propose a neural network-based method for vessel segmentation. A deep supervised fully convolutional network is developed by leveraging multi-level hierarchical features of the deep networks. To improve the discriminative capability of features in lower layers of the deep network and guide the gradient back propagation to overcome gradient vanishing, deep supervision with auxiliary classifiers is incorporated in some intermediate layers of the network. Moreover, the transferred knowledge learned from other domains is used to alleviate the issue of insufficient medical training data. The proposed approach does not rely on hand-crafted features and needs no problem-specific preprocessing or postprocessing, which reduces the impact of subjective factors. We evaluate the proposed method on three publicly available databases, the DRIVE, STARE, and CHASE_DB1 databases. Extensive experiments demonstrate that our approach achieves better or comparable performance to state-of-the-art methods with a much faster processing speed, making it suitable for real-world clinical applications. The results of cross-training experiments demonstrate its robustness with respect to the training set. The proposed approach segments retinal vessels accurately with a much faster processing speed and can be easily applied to other biomedical segmentation tasks.

  15. The application of optical coherence tomography angiography in retinal diseases.

    Science.gov (United States)

    Sambhav, Kumar; Grover, Sandeep; Chalam, Kakarla V

    Optical coherence tomography angiography (OCTA) is a new, noninvasive imaging technique that generates real-time volumetric data on chorioretinal vasculature and its flow pattern. With the advent of high-speed optical coherence tomography, established enface chorioretinal segmentation, and efficient algorithms, OCTA generates images that resemble an angiogram. The principle of OCTA involves determining the change in backscattering between consecutive B-scans and then attributing the differences to the flow of erythrocytes through retinal blood vessels. OCTA has shown promise in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age-related macular degeneration, and retinal vascular occlusions. It quantifies vascular compromise reflecting the severity of diabetic retinopathy. OCTA detects the presence of choroidal neovascularization in exudative age-related macular degeneration and maps loss of choriocapillaris in nonexudative age-related macular degeneration. We describe principles of OCTA and findings in common and some uncommon retinal pathologies. Finally, we summarize its potential future applications. Its current limitations include a relatively small field of view, inability to show leakage, and a tendency for image artifacts. Further larger studies will define OCTAs utility in clinical settings and establish if the technology may offer its utility in decreasing morbidity through early detection and guide therapeutic interventions in retinal diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Retinal diseases in a reference center from a Western Amazon capital city.

    Science.gov (United States)

    Malerbi, Fernando Korn; Matsudo, Nilson Hideo; Carneiro, Adriano Biondi Monteiro; Lottenberg, Claudio Luiz

    2015-01-01

    To describe retinal diseases found in patients who were waiting for treatment at a tertiary care hospital in Rio Branco, Acre, Brazil. Patients underwent slit lamp biomicroscopy, dilated fundus exam and ocular ultrasound. Patients were classified according to phakic status and retinal disease of the most severely affected eye. A total of 138 patients were examined. The mean age was 51.3 years. Diabetes was present in 35.3% and hypertension in 45.4% of these patients. Cataract was found in 23.2% of patients, in at least one eye. Retinal examination was possible in 129 patients. The main retinal diseases identified were rhegmatogenous retinal detachment (n=23; 17.8%) and diabetic retinopathy (n=32; 24.8%). Out of 40 patients evaluated due to diabetes, 13 (32.5%) had absent or mild forms of diabetic retinopathy and did not need further treatment, only observation. Diabetic retinopathy was the main retinal disease in this population. It is an avoidable cause of blindness and can be remotely evaluated, in its initial stages, by telemedicine strategies. In remote Brazilian areas, telemedicine may be an important tool for retinal diseases diagnosis and follow-up.

  17. Retinal vascular changes in hypertensive patients in Ibadan, Sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Oluleye ST

    2016-08-01

    Full Text Available Sunday Tunji Oluleye,1 Bolutife Ayokunu Olusanya,1 Abiodun Moshood Adeoye2 1Department of Ophthalmology, 2Department of Medicine, College of Medicine, University of Ibadan and University College Hospital, Ibadan, Nigeria Background: Earlier studies in Nigeria reported the rarity of retinal vascular changes in hypertensives. The aim of this study was to describe the various retinal vascular changes in the hypertensive patients of Nigeria.Patients and methods: Nine hundred and three hypertensive patients were studied. This study was approved by the ethical and research committee of the University of Ibadan and University College Hospital, Ibadan, Nigeria. Blood pressure and anthropometric measurements were measured. Cardiac echocardiography was performed on 156 patients. All patients had dilated fundoscopy and fundus photography using the Kowa portable fundus camera and an Apple iPhone with 20 D lens. Statistical analysis was done with Statistical Packages for the Social Sciences (Version 21.Results: The mean age of patients was 57 years with a male:female ratio of 1. No retinopathy was found in 556 (61.5% patients. In all, 175 (19.4% patients had features of hypertensive retinopathy. Retinal vascular occlusion was a significant finding in 121 patients (13.4%, of which branch retinal vein occlusion, 43 (4.7%, and central retinal vein occlusion, 30 (3.3%, were the most prominent ones in cases. Hemicentral retinal vein occlusion, 26 (2.9%, and central retinal artery occlusion, 17 (1.9%, were significant presentations. Other findings included nonarteritic anterior ischemic optic neuropathy in five (0.6% patients, hypertensive choroidopathy in seven (0.8% patients, and hemorrhagic choroidal detachment in five (0.6% patients. Left ventricular (LV geometry was abnormal in 85 (55.5% patients. Concentric remodeling, eccentric hypertrophy, and concentric hypertrophy were observed in 43 (27.6%, 26 (17.2%, and 15 (9.7% patients, respectively. LV

  18. Correlation of structure and function of the macula in patients with retinitis pigmentosa.

    Science.gov (United States)

    Battu, R; Khanna, A; Hegde, B; Berendschot, T T J M; Grover, S; Schouten, J S A G

    2015-07-01

    To correlate the structure of the macula, as measured by spectral-domain optical coherence tomography (SD-OCT) and function, as measured by microperimetry (MAIA) in patients with retinitis pigmentosa (RP) and relatively good visual acuity. Prospective, cross-sectional, non-intervention study. Patients with RP. Thirty patients with RP and good central visual acuity were identified. Each patient underwent SD-OCT of the macula and microperimetry. The images were overlaid using the custom-designed software. The retinal sensitivity by microperimetry was correlated with corresponding retinal thickness, as measured by the SD-OCT. ELM, COST, and IS/OS junction were scored as intact, disrupted, or absent. Comparing the retinal sensitivity on the MAIA with various measurements on the SD-OCT. The retinal sensitivity on the MAIA showed a significant correlation with total retinal thickness and outer retinal thickness on the SD-OCT. There was no association with either the inner retinal thickness or the choroidal thickness. ORT showed a statistically significant correlation with the anatomical classification of ELM (r=-0.76, Pmacula in patients with RP. These studies are important to establish surrogate markers that can be used as end points for various tests in future therapeutic clinical trials.

  19. Correlation between the optical coherence tomography and electroretinogram in retinal vein occlusion macular edema

    Directory of Open Access Journals (Sweden)

    Ya Xu

    2014-11-01

    Full Text Available AIM: To evaluate the correlation between retinal thickness and photopic flash electroretinogram(ERGparameters(Cone a-wave, Cone b-wave, and 30Hz flickerin patients with central retinal vein occlusion(CRVOand macular edema. METHODS: A total of 25 patients(25 CRVO eyes and 25 unaffected fellow eyeswith CRVO underwent the examination of optical coherence tomography(OCTand photopic falsh ERG. The amplitude and implicit time of the ERG parameters were extracted from the ERG traces. Retinal thicknesses were measured by OCT in nine macular subfields. Then the correlations between ERG parameters and macular morphological parameters were analyzed. RESULTS: The Cone b-wave and 30Hz flicker implicit time were correlated with macular retinal thickness in seven out of nine subfields, excluding the temporal subfields. CONCLUSION: The retinal thickness of the macular edema may be associated with inner retinal function in CRVO patients.

  20. Fast vessel segmentation in retinal images using multi-scale enhancement and second-order local entropy

    Science.gov (United States)

    Yu, H.; Barriga, S.; Agurto, C.; Zamora, G.; Bauman, W.; Soliz, P.

    2012-03-01

    Retinal vasculature is one of the most important anatomical structures in digital retinal photographs. Accurate segmentation of retinal blood vessels is an essential task in automated analysis of retinopathy. This paper presents a new and effective vessel segmentation algorithm that features computational simplicity and fast implementation. This method uses morphological pre-processing to decrease the disturbance of bright structures and lesions before vessel extraction. Next, a vessel probability map is generated by computing the eigenvalues of the second derivatives of Gaussian filtered image at multiple scales. Then, the second order local entropy thresholding is applied to segment the vessel map. Lastly, a rule-based decision step, which measures the geometric shape difference between vessels and lesions is applied to reduce false positives. The algorithm is evaluated on the low-resolution DRIVE and STARE databases and the publicly available high-resolution image database from Friedrich-Alexander University Erlangen-Nuremberg, Germany). The proposed method achieved comparable performance to state of the art unsupervised vessel segmentation methods with a competitive faster speed on the DRIVE and STARE databases. For the high resolution fundus image database, the proposed algorithm outperforms an existing approach both on performance and speed. The efficiency and robustness make the blood vessel segmentation method described here suitable for broad application in automated analysis of retinal images.

  1. Postoperative blood salvage versus allogeneic blood transfusion in total knee and hip arthroplasty: a literature review.

    Science.gov (United States)

    Leigheb, Massimiliano; Pogliacomi, Francesco; Bosetti, Michela; Boccafoschi, Francesca; Sabbatini, Maurizio; Cannas, Mario; Grassi, Federico

    2016-04-15

    We aimed to compare Postoperative Blood Salvage (PBS) with Allogeneic Blood Transfusion (ABT) in patients undergoing Total Hip and Knee Arthroplasty (THA, TKA).  A bibliographic research was carried out in order to review the literature dedicated to postoperative blood salvage in major orthopaedic surgery, excluding papers dealing exclusively with preoperative autologous donation, intraoperative blood salvage and ABT. PBS and ABT were compared according to complications, costs and duration of hospitalization. PBS effectiveness in reducing ABT was also assessed. PBS system is useful for reducing the complication rate and the length of hospital stay if compared to ABT. Costs for the reinfusion of unwashed shed blood, washed blood, and allogeneic transfusion are controversial among the different authors. Several papers demonstrate that PBS significantly reduces the need of postoperative ABT in both THA and TKA, while there is low evidence that PBS does not affect the risk of surgical wound complications. To reduce potential risks related to PBS, including non-hemolytic febrile reaction, the reinfusion of saved blood should begin within 4-6 hours after the start of collection through the wound drainage. According to literature, PBS appears to be a valid alternative to ABT, which is the standard treatment for postoperative anemia in THA and TKA. Contraindications to PBS must be ruled out before recommending it to patients undergoing major orthopaedic procedures.

  2. Differential diagnosis of retinal vasculitis.

    Science.gov (United States)

    Abu El-Asrar, Ahmed M; Herbort, Carl P; Tabbara, Khalid F

    2009-10-01

    Retinal vaculitis is a sight-threatening inflammatory eye condition that involves the retinal vessels. Detection of retinal vasculitis is made clinically, and confirmed with the help of fundus fluorescein angiography. Active vascular disease is characterized by exudates around retinal vessels resulting in white sheathing or cuffing of the affected vessels. In this review, a practical approach to the diagnosis of retinal vasculitis is discussed based on ophthalmoscopic and fundus fluorescein angiographic findings.

  3. Retinal pigmentary changes in chronic uveitis mimicking retinitis pigmentosa.

    Science.gov (United States)

    Sevgi, D Damla; Davoudi, Samaneh; Comander, Jason; Sobrin, Lucia

    2017-09-01

    To present retinal pigmentary changes mimicking retinitis pigmentosa (RP) as a finding of advanced uveitis. We retrospectively reviewed charts of patients without a family history of inherited retinal degenerations who presented with retinal pigment changes and signs of past or present intraocular inflammation. Comprehensive eye examination including best-corrected visual acuity, slit-lamp examination and dilated fundus examination was performed on all patients in addition to color fundus photography, optical coherence tomography, fluorescein angiography (FA), and full-field electroretinogram testing. We identified five patients with ages ranging from 33 to 66 years, who presented with RP-like retinal pigmentary changes which were eventually attributed to longstanding uveitis. The changes were bilateral in three cases and unilateral in two cases. Four of five cases presented with active inflammation, and the remaining case showed evidence of active intraocular inflammation during follow-up. This study highlights the overlapping features of advanced uveitis and RP including the extensive pigmentary changes. Careful review of possible past uveitis history, detailed examination of signs of past or present inflammation and ancillary testing, with FA often being most helpful, are required for the correct diagnosis. This is important, because intervention can prevent further damage if the cause of the pigmentary changes is destructive inflammation.

  4. Blood volume, blood pressure and total body sodium: internal signalling and output control

    DEFF Research Database (Denmark)

    Bie, P

    2009-01-01

    Total body sodium and arterial blood pressure (ABP) are mutually dependent variables regulated by complex control systems. This review addresses the role of ABP in the normal control of sodium excretion (NaEx), and the physiological control of renin secretion. NaEx is a pivotal determinant of ABP......, and under experimental conditions, ABP is a powerful, independent controller of NaEx. Blood volume is a function of dietary salt intake; however, ABP is not, at least not in steady states. A transient increase in ABP after a step-up in sodium intake could provide a causal relationship between ABP...... and the regulation of NaEx via a hypothetical integrative control system. However, recent data show that subtle sodium loading (simulating salty meals) causes robust natriuresis without changes in ABP. Changes in ABP are not necessary for natriuresis. Normal sodium excretion is not regulated by pressure. Plasma...

  5. The effect of total blood exchange with PHP solution on cardiac xenotransplantation.

    Science.gov (United States)

    Liu, H; Agishi, T; Suga, H; Hayasaka, Y; Teraoka, S; Ota, K

    1995-04-01

    Prevention of hyperacute rejection is a difficult and unsolved problem in xenotransplantation. Natural antibodies and complement activation have been known to play an important role in the xenotransplantation between discordant species pairs. In the present study, total blood exchange (TBE) was performed with pyridoxalated-hemoglobin-polyoxyethylene conjugate (PHP) solution (Ajinomoto Co., Inc., Kawasaki, Japan) before cardiac xenotransplantation in order to remove the immunoglobulins and prolong xenograft survival time. Guinea pigs and rats were used as the discordant species combination for donor and recipient. Two groups were established: Group 1, untreated control (n = 8) and Group 2, TBT with PHP solution (n = 8). The exchange blood transfusion was carried out at the rate of 15-20 ml/h utilizing PHP solution using a blood pump. After the blood exchange was processed, hematocrit (Ht) levels dropped to 4 or 5%, and a cardiac xenotransplantation was performed within 24 h. The levels of serum IgA, IgM, and IgG were decreased to less than 25, 25, and 10% of the base line, respectively, after blood exchange. A mean xenograft survival time in Group 2 was prolonged to 472 +/- 74 min and to 10.4 +/- 1.8 min in Group 1 (p < 0.01). A titer of the anti-guinea pig lymphocytotoxic antibody in rat serum was decreased to almost nil. The data from this study suggest that total blood exchange with PHP solution may be useful in preoperative removal of xenograft antibodies in xenotransplantation.

  6. Epsilon Aminocaproic Acid to Reduce Blood Loss and Transfusion After Total Hip and Total Knee Arthroplasty.

    Science.gov (United States)

    Hobbs, Juliann C; Welsby, Ian J; Green, Cynthia L; Dhakal, Ishwori B; Wellman, Samuel S

    2018-01-01

    Total hip and knee arthroplasty (THA and TKA) are associated with significant blood loss and some patients require postoperative blood transfusion. While tranexamic acid has been studied extensively among this population, we tested the hypothesis that epsilon aminocaproic acid (EACA) can reduce blood loss and transfusion after joint arthroplasty. In April 2014, our Veterans Affairs Medical Center introduced a protocol to administer EACA during THA and TKA. No antifibrinolytics were used previously. We retrospectively compared blood loss and incidence of transfusion among patients who underwent primary arthroplasty in the year before standardized administration of EACA with patients having the same procedures the following year. Blood loss was measured as delta hemoglobin (preoperative hemoglobin - hemoglobin on postoperative day 1). All patients undergoing primary THA or TKA were included. Patients having revision surgery were excluded. We identified 185 primary arthroplasty patients from the year before and 184 from the year after introducing the EACA protocol. There were no changes in surgical technique or attending surgeons during this period. Delta hemoglobin was significantly lower in the EACA group (2.7 ± 0.8 mg/dL) compared to the control group (3.4 ± 1.1 mg/dL) (P blood transfusion was also significantly lower in the EACA group (2.7%) compared to the control group (25.4%) (P transfusion following introduction of the EACA protocol in patients undergoing primary arthroplasty. EACA offers a lower cost alternative to TXA for reducing blood loss and transfusion in this population. Published by Elsevier Inc.

  7. Maternal blood total oxypurines and erythrocyte 2,3-diphosphoglycerate levels during normal pregnancy.

    Science.gov (United States)

    Mizutani, S; Akiyama, H; Kurauchi, O; Taira, H; Yamada, R; Narita, O; Tomoda, Y

    1985-01-01

    The effects of pregnancy on the levels of maternal plasma total oxypurines (hypoxanthine, xanthine and uric acid) and erythrocyte 2,3-diphosphoglycerate (2,3-DPG) was investigated. With advancing gestation there was a slight increasing tendency in plasma total oxypurines as well as erythrocyte 2,3-DPG in pregnant women. When the ratio of 2,3-DPG to total oxypurines was calculated, the ratio was almost unchanged until week 34. After week 35, the ratio decreased to week 37; the ratios between week 37 and 40 had similar values to cord blood. The above data suggest that the changes of these metabolites in maternal peripheral blood may be indicative for hypoxia with fetoplacental tissue.

  8. A comparison of total amount of blood needed in patients taking autologous or homologous blood transfusion in coronary artery bypass grafting a clinical randomized case control trial

    International Nuclear Information System (INIS)

    Akhlagh, S.H.; Chohedri, A.H.; Bazojoo, A.; Nemati, M.H.

    2007-01-01

    The aim of this clinical case-control trial was to compare the total amount of blood needed in patients taking autologous or homologous blood transfusion in coronary artery bypass grafting (CABG) surgery. Sixty patients scheduled for CABG were randomly allocated to ANH (Acute Normovulemic Hemodynamic) group (A group) or control group (B group). Hematocrit before operation and 24 hours after the operation were checked. The amount of the total blood needed in each group was measured at the end of the operation. There was no significant difference between the two groups as regards post operational hematocrit. The mean total blood infused to the control and ANH group was 2010 ml and 1815 ml respectively. However there was significant difference between the two groups as regards the total amount of the blood needed during operation. Our randomized, double blinded case control study demonstrated that autologous blood, beside carrying lower risks for hemolytic and nonhemolytic transfusion reactions decrease the total amount of blood needed for CABG. However larger studies with more patients are needed to confirm the results. (author)

  9. Repetitive magnetic stimulation improves retinal function in a rat model of retinal dystrophy

    Science.gov (United States)

    Rotenstreich, Ygal; Tzameret, Adi; Levi, Nir; Kalish, Sapir; Sher, Ifat; Zangen, Avraham; Belkin, Michael

    2014-02-01

    Vision incapacitation and blindness associated with retinal dystrophies affect millions of people worldwide. Retinal degeneration is characterized by photoreceptor cell death and concomitant remodeling of remaining retinal cells. Repetitive Magnetic Stimulation (RMS) is a non-invasive technique that creates alternating magnetic fields by brief electric currents transmitted through an insulated coil. These magnetic field generate action potentials in neurons, and modulate the expression of neurotransmitter receptors, growth factors and transcription factors which mediate plasticity. This technology has been proven effective and safe in various psychiatric disorders. Here we determined the effect of RMS on retinal function in Royal College of Surgeons (RCS) rats, a model for retinal dystrophy. Four week-old RCS and control Spargue Dawley (SD) rats received sham or RMS treatment over the right eye (12 sessions on 4 weeks). RMS treatment at intensity of at 40% of the maximal output of a Rapid2 stimulator significantly increased the electroretinogram (ERG) b-wave responses by up to 6- or 10-fold in the left and right eye respectively, 3-5 weeks following end of treatment. RMS treatment at intensity of 25% of the maximal output did not significant effect b-wave responses following end of treatment with no adverse effect on ERG response or retinal structure of SD rats. Our findings suggest that RMS treatment induces delayed improvement of retinal functions and may induce plasticity in the retinal tissue. Furthermore, this non-invasive treatment may possibly be used in the future as a primary or adjuvant treatment for retinal dystrophy.

  10. Rhegmatogenous retinal detachment in an eye of retinoblastoma treated by radiation and cryocoagulation

    International Nuclear Information System (INIS)

    Inoue, Makoto; Tanaka, Yasuhiko; Kawai, Masataka; Nii, Seiji; Katsura, Hiroshi; Kaneko, Akihiro

    1999-01-01

    A 4-month-old female infant was diagnosed as bilateral retinoblastoma. The left eye was treated by enucleation and the right by radiation. The right eye received repeated thermochemotherapy, cryocoagulation and photocoagulation for recurrence. Total retinal detachment was detected after surgery for complicated cataract at the age of 2 years 9 months. Vitreous surgery led to the detection of posterior vitreous detachment and retinal breaks in the coagulated scar areas with vitreoretinal adhesion around the calcified tumor. During the following one year, the retina has been attached with no reoccurrence of the tumor. This case illustrates that rhegmatogenous retinal detachment is a possibility in retinoblastoma treated by radiation or retinal coagulations. (author)

  11. Automated detection of kinks from blood vessels for optic cup segmentation in retinal images

    Science.gov (United States)

    Wong, D. W. K.; Liu, J.; Lim, J. H.; Li, H.; Wong, T. Y.

    2009-02-01

    The accurate localization of the optic cup in retinal images is important to assess the cup to disc ratio (CDR) for glaucoma screening and management. Glaucoma is physiologically assessed by the increased excavation of the optic cup within the optic nerve head, also known as the optic disc. The CDR is thus an important indicator of risk and severity of glaucoma. In this paper, we propose a method of determining the cup boundary using non-stereographic retinal images by the automatic detection of a morphological feature within the optic disc known as kinks. Kinks are defined as the bendings of small vessels as they traverse from the disc to the cup, providing physiological validation for the cup boundary. To detect kinks, localized patches are first generated from a preliminary cup boundary obtained via level set. Features obtained using edge detection and wavelet transform are combined using a statistical approach rule to identify likely vessel edges. The kinks are then obtained automatically by analyzing the detected vessel edges for angular changes, and these kinks are subsequently used to obtain the cup boundary. A set of retinal images from the Singapore Eye Research Institute was obtained to assess the performance of the method, with each image being clinically graded for the CDR. From experiments, when kinks were used, the error on the CDR was reduced to less than 0.1 CDR units relative to the clinical CDR, which is within the intra-observer variability of 0.2 CDR units.

  12. Bilateral patching in retinal detachment: fluid mechanics and retinal "settling".

    Science.gov (United States)

    Foster, William J

    2011-07-20

    When a patient suffers a retinal detachment and surgery is delayed, it is known clinically that bilaterally patching the patient may allow the retina to partially reattach or "settle." Although this procedure has been performed since the 1860s, there is still debate as to how such a maneuver facilitates the reattachment of the retina. Finite element calculations using commercially available analysis software are used to elucidate the influence of reduction in eye movement caused by bilateral patching on the flow of subretinal fluid in a physical model of retinal detachment. It was found that by coupling fluid mechanics with structural mechanics, a physically consistent explanation of increased retinal detachment with eye movements can be found in the case of traction on the retinal hole. Large eye movements increase vitreous traction and detachment forces on the edge of the retinal hole, creating a subretinal vacuum and facilitating increased subretinal fluid. Alternative models, in which intraocular fluid flow is redirected into the subretinal space, are not consistent with these simulations. The results of these simulations explain the physical principles behind bilateral patching and provide insight that can be used clinically. In particular, as is known clinically, bilateral patching may facilitate a decrease in the height of a retinal detachment. The results described here provide a description of a physical mechanism underlying this technique. The findings of this study may aid in deciding whether to bilaterally patch patients and in counseling patients on pre- and postoperative care.

  13. Retinal vascular caliber, iris color, and age-related macular degeneration in the Irish Nun Eye Study.

    Science.gov (United States)

    McGowan, Amy; Silvestri, Giuliana; Moore, Evelyn; Silvestri, Vittorio; Patterson, Christopher C; Maxwell, Alexander P; McKay, Gareth J

    2014-12-18

    To evaluate the relationship between retinal vascular caliber (RVC), iris color, and age-related macular degeneration (AMD) in elderly Irish nuns. Data from 1233 participants in the cross-sectional observational Irish Nun Eye Study were assessed from digital photographs with a standardized protocol using computer-assisted software. Macular images were graded according to the modified Wisconsin Age-related Maculopathy Grading System. Regression models were used to assess associations, adjusting for age, mean arterial blood pressure, body mass index, refraction, and fellow RVC. In total, 1122 (91%) participants had gradable retinal images of sufficient quality for vessel assessment (mean age: 76.3 years [range, 56-100 years]). In an unadjusted analysis, we found some support for a previous finding that individuals with blue iris color had narrower retinal venules compared to those with brown iris color (P < 0.05), but this was no longer significant after adjustment. Age-related macular degeneration status was categorized as no AMD, any AMD, and late AMD only. Individuals with any AMD (early or late AMD) had significantly narrower arterioles and venules compared to those with no AMD in an unadjusted analysis, but this was no longer significant after adjustment. A nonsignificant reduced risk of any AMD or late AMD only was observed in association with brown compared to blue iris color, in both unadjusted and adjusted analyses. Retinal vascular caliber was not significantly associated with iris color or early/late AMD after adjustment for confounders. A lower but nonsignificant AMD risk was observed in those with brown compared to blue iris color. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  14. Liraglutide attenuates the migration of retinal pericytes induced by advanced glycation end products.

    Science.gov (United States)

    Lin, Wen-Jian; Ma, Xue-Fei; Hao, Ming; Zhou, Huan-Ran; Yu, Xin-Yang; Shao, Ning; Gao, Xin-Yuan; Kuang, Hong-Yu

    2018-07-01

    Retinal pericyte migration represents a novel mechanism of pericyte loss in diabetic retinopathy (DR), which plays a crucial role in the early impairment of the blood-retinal barrier (BRB). Glucagon-like peptide-1 (GLP-1) has been shown to protect the diabetic retina in the early stage of DR; however, the relationship between GLP-1 and retinal pericytes has not been discussed. In this study, advanced glycation end products (AGEs) significantly increased the migration of primary bovine retinal pericytes without influencing cell viability. AGEs also significantly enhanced phosphatidylinositol 3-kinase (PI3K)/Akt activation, and changed the expressions of migration-related proteins, including phosphorylated focal adhesion kinase (p-FAK), matrix metalloproteinase (MMP)-2 and vinculin. PI3K inhibition significantly attenuated the AGEs-induced migration of retinal pericytes and reversed the overexpression of MMP-2. Glucagon-like peptide-1 receptor (Glp1r) was expressed in retinal pericytes, and liraglutide, a GLP-1 analog, significantly attenuated the migration of pericytes by Glp1r and reversed the changes in p-Akt/Akt, p-FAK/FAK, vinculin and MMP-2 levels induced by AGEs, indicating that the protective effect of liraglutide was associated with the PI3K/Akt pathway. These results provided new insights into the mechanism underlying retinal pericyte migration. The early use of liraglutide exerts a potential bebefical effect on regulating pericyte migration, which might contribute to mechanisms that maintain the integrity of vascular barrier and delay the development of DR. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. FACTORS ASSOCIATED WITH VISUAL OUTCOME AFTER MACULA-OFF RHEGMATOGENOUS RETINAL DETACHMENT SURGERY.

    Science.gov (United States)

    Park, Dae Hyun; Choi, Kyung Seek; Sun, Hae Jung; Lee, Sung Jin

    2018-01-01

    To evaluate preoperative factors influencing the visual outcome and postoperative factors associated with the changes in visual acuity, after reattachment surgery to treat macula-off rhegmatogenous retinal detachment. A total of 180 eyes of 180 patients who underwent reattachment surgery to treat macula-off rhegmatogenous retinal detachment, and who were followed up for more than 12 months, were reviewed retrospectively. Preoperative and postoperative characteristics, including optical coherence tomography findings, were comprehensively analyzed using univariate and multivariate models to evaluate preoperative factors influencing best-corrected visual acuity 12 months after macula-off rhegmatogenous retinal detachment surgery and postoperative factors associated with changes in best-corrected visual acuity after surgery. Preoperatively, the extent of detachment (P = 0.037), macula-off duration (P macula-off rhegmatogenous retinal detachment surgery were the extent of detachment, macula-off duration, and external limiting membrane integrity. Postoperatively, predictive factors were the outer retinal microstructures, particularly the photoreceptor outer segment layer.

  16. Churg-Strauss syndrome associated with antiphospholipid antibodies in a patient with retinal vasculitis.

    Science.gov (United States)

    Sánchez-Vicente, J L; Gálvez-Carvajal, S; Medina-Tapia, A; Rueda, T; González-García, L; Szewc, M; Muñoz-Morales, A

    2016-11-01

    We present the case of a 69-year-old woman with unilateral retinal vasculitis. Investigations showed asthma, rhinosinusitis, nasal polyposis, peripheral blood eosinophilia, increased sedimentation rate, proteinuria, and antiphospholipid antibodies. Anti-neutrophil cytoplasmic antibodies (ANCA) were negative. Although her anti-neutrophil cytoplasmatic antibody (ANCA) status was negative, taking into account the other clinical and laboratory features, retinal vasculitis was thought to be an ocular manifestation of Churg-Strauss syndrome. Treatment was started with high-dose corticosteroids and anticoagulant therapy. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Fundus Autofluorescence and Optical Coherence Tomography Findings in Branch Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    Tetsuju Sekiryu

    2012-01-01

    Full Text Available Purpose. To describe the findings of fundus autofluorescence (FAF and optical coherence tomography (OCT in patients with branch retinal vein occlusion (BRVO. Methods. In this institutional, retrospective, observational case series, FAF was evaluated in 65 eyes with BRVO in 64 consecutive patients and compared with visual acuity, OCT findings, and other clinical observations. Results. Five types of autofluorescence appeared during the course of BRVO: (1 petaloid-shaped hyperautofluorescence in the area of macular edema and (2 hyperautofluorescence coincident with yellow subretinal deposits. (3 Diffuse hyperautofluorescence appeared within the area of serous retinal detachment (SRD and OCT showed precipitates on the undersurface of the retina in 5/5 of these eyes (100%. (4 The area of vein occlusion showed diffuse hyperautofluorescence after resolution of the retinal bleeding. (5 Hard exudates exhibited hyper- or hypoautofluorescence. OCT indicated that most of the hard exudates with hyperautofluorescence were located on the retinal pigment epithelium. Conclusions. Hyperautofluorescence associated with subretinal fluid or hard exudate appeared in the subretinal space. This type of hyperautofluorescence may be attributed to blood cell or macrophages. FAF and OCT are noninvasive modalities that provide additional information regarding macular edema due to BRVO.

  18. Eriodictyol prevents early retinal and plasma abnormalities in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Bucolo, Claudio; Leggio, Gian Marco; Drago, Filippo; Salomone, Salvatore

    2012-07-01

    Diabetic retinopathy is a complex disease that has potential involvement of inflammatory and oxidative stress-related pathways in its pathogenesis. We hypothesized that eriodictyol, one of the most abundant dietary flavonoids, could be effective against diabetic retinopathy, which involves significant oxidative stress and inflammation. The aim of the present study was to investigate the effects of eriodictyol in early retinal and plasma changes of streptozotocin-induced diabetic rats. The effect of eriodictyol treatment (0.1, 1, 10 mg/kg daily for 10 days) was evaluated by TNF-α, ICAM-1, VEGF, and eNOS protein levels measurement in the retina, plasma lipid peroxidation, and blood-retinal barrier (BRB) integrity. Increased amounts of cytokines, adhesion molecule, and nitric oxide synthase were observed in retina from diabetic rats. Eriodictyol treatment significantly lowered retinal TNF-α, ICAM-1, VEGF, and eNOS in a dose-dependent manner. Further, treatment with eriodictyol significantly suppressed diabetes-related lipid peroxidation, as well as the BRB breakdown. These data demonstrated that eriodictyol attenuates the degree of retinal inflammation and plasma lipid peroxidation preserving the BRB in early diabetic rats. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Ursodeoxycholic Acid Attenuates Endoplasmic Reticulum Stress-Related Retinal Pericyte Loss in Streptozotocin-Induced Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Yoo-Ri Chung

    2017-01-01

    Full Text Available Loss of pericytes, an early hallmark of diabetic retinopathy (DR, results in breakdown of the blood-retinal barrier. Endoplasmic reticulum (ER stress may be involved in this process. The purpose of this study was to examine the effects of ursodeoxycholic acid (UDCA, a known ameliorator of ER stress, on pericyte loss in DR of streptozotocin- (STZ- induced diabetic mice. To assess the extent of DR, the integrity of retinal vessels and density of retinal capillaries in STZ-induced diabetic mice were evaluated. Additionally, induction of ER stress and the unfolded protein response (UPR were assessed in diabetic mice and human retinal pericytes exposed to advanced glycation end products (AGE or modified low-density lipoprotein (mLDL. Fluorescein dye leakage during angiography and retinal capillary density were improved in UDCA-treated diabetic mice, compared to the nontreated diabetic group. Among the UPR markers, those involved in the protein kinase-like ER kinase (PERK pathway were increased, while UDCA attenuated UPR in STZ-induced diabetic mice as well as AGE- or mLDL-exposed retinal pericytes in culture. Consequently, vascular integrity was improved and pericyte loss reduced in the retina of STZ-induced diabetic mice. Our findings suggest that UDCA might be effective in protecting against DR.

  20. Α-Melanocyte-Stimulating Hormone Protects Early Diabetic Retina from Blood-Retinal Barrier Breakdown and Vascular Leakage via MC4R.

    Science.gov (United States)

    Cai, Siwei; Yang, Qianhui; Hou, Mengzhu; Han, Qian; Zhang, Hanyu; Wang, Jiantao; Qi, Chen; Bo, Qiyu; Ru, Yusha; Yang, Wei; Gu, Zhongxiu; Wei, Ruihua; Cao, Yunshan; Li, Xiaorong; Zhang, Yan

    2018-01-01

    Blood-retinal barrier (BRB) breakdown and vascular leakage is the leading cause of blindness of diabetic retinopathy (DR). Hyperglycemia-induced oxidative stress and inflammation are primary pathogenic factors of this severe DR complication. An effective interventional modality against the pathogenic factors during early DR is needed to curb BRB breakdown and vascular leakage. This study sought to examine the protective effects of α-Melanocyte-stimulating hormone (α-MSH) on early diabetic retina against vascular hyperpermeability, electrophysiological dysfunction, and morphological deterioration in a rat model of diabetes and probe the mechanisms underlying the α-MSH's anti-hyperpermeability in both rodent retinas and simian retinal vascular endothelial cells (RF6A). Sprague Dawley rats were injected through tail vein with streptozotocin to induce diabetes. The rats were intravitreally injected with α-MSH or saline at Week 1 and 3 after hyperglycemia. In another 2 weeks, Evans blue assay, transmission electron microscopy, electroretinogram (ERG), and hematoxylin and eosin (H&E) staining were performed to examine the protective effects of α-MSH in diabetic retinas. The expression of pro-inflammatory factors and tight junction at mRNA and protein levels in retinas was analyzed. Finally, the α-MSH's anti-hyperpermeability was confirmed in a high glucose (HG)-treated RF6A cell monolayer transwell culture by transendothelial electrical resistance (TEER) measurement and a fluorescein isothiocyanate-Dextran assay. Universal or specific melanocortin receptor (MCR) blockers were also employed to elucidate the MCR subtype mediating α-MSH's protection. Evans blue assay showed that BRB breakdown and vascular leakage was detected, and rescued by α-MSH both qualitatively and quantitatively in early diabetic retinas; electron microscopy revealed substantially improved retinal and choroidal vessel ultrastructures in α-MSH-treated diabetic retinas; scotopic ERG suggested

  1. 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...

  2. Metabolic Memory Phenomenon and Accumulation of Peroxynitrite in Retinal Capillaries

    Directory of Open Access Journals (Sweden)

    Renu A. Kowluru

    2007-01-01

    Full Text Available Aim. Diabetic retinopathy resists reversal after good glycemic control (GC is reinitiated, and preexisting damage at the time of intervention is considered as the major factor in determining the outcome of the GC. This study is to investigate the role of peroxynitrite accumulation in the retinal capillaries in the failure of retinopathy to reverse after reestablishment of GC, and to determine the effect of this reversal on the activity of the enzyme responsible for scavenging mitochondrial superoxide, MnSOD. Methods. In streptozotocin-diabetic rats, 6 months of poor glycemic control (PC, glycated hemoglobin, GHb>12.0% was followed by 6 additional months of GC (GHb about 6%. The trypsin-digested retinal microvessels were prepared for immunostaining of nitrotyrosine (a measure of peroxynitrite and for counting the number of acellular capillaries (a measure of histopathology. The retina from the other eye was used to quantify nitrotyrosine concentration, MnSOD activity and the total antioxidant capacity. Results. Reversal of hyperglycemia after 6 months of PC had no significant effect on nitrotyrosine concentration in the retina, on the nitrotyrosine-positive retinal capillary cells and on the number of acellular capillaries; the values were similar in PC-GC and PC groups. In the same rats retinal MnSOD activity remained inhibited and the total antioxidant capacity was subnormal 6 months after cessation of PC. Conclusions. Peroxynitrite accumulation in the retinal microvasculature, the site of histopathology, fails to normalize after reversal of hyperglycemia, and superoxide remains inadequately scavenged. This failure of reversal of peroxynitrite accumulation could be, in part, responsible for the resistance of diabetic retinopathy to reverse after termination of PC.

  3. Congenital Retinal Macrovessel and the Association of Retinal Venous Malformations With Venous Malformations of the Brain.

    Science.gov (United States)

    Pichi, Francesco; Freund, K Bailey; Ciardella, Antonio; Morara, Mariachiara; Abboud, Emad B; Ghazi, Nicola; Dackiw, Christine; Choudhry, Netan; Souza, Eduardo Cunha; Cunha, Leonardo Provetti; Arevalo, J Fernando; Liu, T Y Alvin; Wenick, Adam; He, Lingmin; Villarreal, Guadalupe; Neri, Piergiorgio; Sarraf, David

    2018-04-01

    Congenital retinal macrovessel (CRM) is a rarely reported venous malformation of the retina that is associated with venous anomalies of the brain. To study the multimodal imaging findings of a series of eyes with congenital retinal macrovessel and describe the systemic associations. In this cross-sectional multicenter study, medical records were retrospectively reviewed from 7 different retina clinics worldwide over a 10-year period (2007-2017). Patients with CRM, defined as an abnormal, large, macular vessel with a vascular distribution above and below the horizontal raphe, were identified. Data were analyzed from December 2016 to August 2017. Clinical information and multimodal retinal imaging findings were collected and studied. Pertinent systemic information, including brain magnetic resonance imaging findings, was also noted if available. Of the 49 included patients, 32 (65%) were female, and the mean (SD) age at onset was 44.0 (20.9) years. A total of 49 eyes from 49 patients were studied. Macrovessel was unilateral in all patients. Color fundus photography illustrated a large aberrant dilated and tortuous retinal vein in all patients. Early-phase frames of fluorescein angiography further confirmed the venous nature of the macrovessel in 40 of 40 eyes. Optical coherence tomography angiography, available in 17 eyes (35%), displayed microvascular capillary abnormalities around the CRM, which were more evident in the deep capillary plexus. Of the 49 patients with CRM, 39 (80%) did not illustrate any evidence of ophthalmic complications. Ten patients (20%) presented with retinal complications, typically an incidental association with CRM. Twelve patients (24%) were noted to have venous malformations of the brain with associated magnetic resonance imaging. Of these, location of the venous anomaly in the brain was ipsilateral to the CRM in 10 patients (83%) and contralateral in 2 patients (17%), mainly located in the frontal lobe in 9 patients (75%). Our study has

  4. 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...

  5. Frequency of lattice degeneration and retinal breaks in the fellow eye in retinal detachment.

    Science.gov (United States)

    Lorentzen, S E

    1988-04-01

    The fellow eye of 100 consecutively admitted cases of retinal detachment was studied with three-mirror examination for the presence of lattice degeneration and retinal breaks. Lattice degeneration was found in 18% and retinal breaks in 20% of fellow eyes.

  6. Association of Retinopathy and Retinal Microvascular Abnormalities With Stroke and Cerebrovascular Disease.

    Science.gov (United States)

    Hughes, Alun D; Falaschetti, Emanuela; Witt, Nicholas; Wijetunge, Sumangali; Thom, Simon A McG; Tillin, Therese; Aldington, Steve J; Chaturvedi, Nish

    2016-11-01

    Abnormalities of the retinal circulation may be associated with cerebrovascular disease. We investigated associations between retinal microvascular abnormalities and (1) strokes and subclinical cerebral infarcts and (2) cerebral white matter lesions in a UK-based triethnic population-based cohort. A total of 1185 participants (age, 68.8±6.1 years; 77% men) underwent retinal imaging and cerebral magnetic resonance imaging. Cerebral infarcts and white matter hyperintensities were identified on magnetic resonance imaging, retinopathy was graded, and retinal vessels were measured. Higher retinopathy grade (odds ratio [OR], 1.40 [95% confidence interval (95% CI), 1.16-1.70]), narrower arteriolar diameter (OR, 0.98 [95% CI, 0.97-0.99]), fewer symmetrical arteriolar bifurcations (OR, 0.84 [95% CI, 0.75-0.95]), higher arteriolar optimality deviation (OR, 1.16 [95% CI, 1.00-1.34]), and more tortuous venules (OR, 1.20 [95% CI, 1.09-1.32]) were associated with strokes/infarcts and white matter hyperintensities. Associations with quantitative retinal microvascular measures were independent of retinopathy. Abnormalities of the retinal microvasculature are independently associated with stroke, cerebral infarcts, and white matter lesions. © 2016 American Heart Association, Inc.

  7. Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment

    Science.gov (United States)

    Lee, Christine; Tu, Hong Anh; Weir, Mark; Holubowich, Corinne

    2016-01-01

    Background Retinitis pigmentosa is a group of genetic disorders that involves the breakdown and loss of photoreceptors in the retina, resulting in progressive retinal degeneration and eventual blindness. The Argus II Retinal Prosthesis System is the only currently available surgical implantable device approved by Health Canada. It has been shown to improve visual function in patients with severe visual loss from advanced retinitis pigmentosa. The objective of this analysis was to examine the clinical effectiveness, cost-effectiveness, budget impact, and safety of the Argus II system in improving visual function, as well as exploring patient experiences with the system. Methods We performed a systematic search of the literature for studies examining the effects of the Argus II retinal prosthesis system in patients with advanced retinitis pigmentosa, and appraised the evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria, focusing on visual function, functional outcomes, quality of life, and adverse events. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care over a 10-year time horizon. We also conducted a 5-year budget impact analysis. We used a qualitative design and an interview methodology to examine patients’ lived experience, and we used a modified grounded theory methodology to analyze information from interviews. Transcripts were coded, and themes were compared against one another. Results One multicentre international study and one single-centre study were included in the clinical review. In both studies, patients showed improved visual function with the Argus II system. However, the sight-threatening surgical complication rate was substantial. In the base-case analysis, the Argus II system was cost-effective compared with standard care only if willingness-to-pay was more than $207,616 per quality-adjusted life

  8. Ultra-Widefield Steering-Based Spectral-Domain Optical Coherence Tomography Imaging of the Retinal Periphery.

    Science.gov (United States)

    Choudhry, Netan; Golding, John; Manry, Matthew W; Rao, Rajesh C

    2016-06-01

    To describe the spectral-domain optical coherence tomography (SD OCT) features of peripheral retinal findings using an ultra-widefield (UWF) steering technique to image the retinal periphery. Observational study. A total of 68 patients (68 eyes) with 19 peripheral retinal features. Spectral-domain OCT-based structural features. Nineteen peripheral retinal features, including vortex vein, congenital hypertrophy of the retinal pigment epithelium, pars plana, ora serrata pearl, typical cystoid degeneration (TCD), cystic retinal tuft, meridional fold, lattice and cobblestone degeneration, retinal hole, retinal tear, rhegmatogenous retinal detachment, typical degenerative senile retinoschisis, peripheral laser coagulation scars, ora tooth, cryopexy scars (retinal tear and treated retinoblastoma scar), bone spicules, white without pressure, and peripheral drusen, were identified by peripheral clinical examination. Near-infrared scanning laser ophthalmoscopy images and SD OCT of these entities were registered to UWF color photographs. Spectral-domain OCT resolved structural features of all peripheral findings. Dilated hyporeflective tubular structures within the choroid were observed in the vortex vein. Loss of retinal lamination, neural retinal attenuation, retinal pigment epithelium loss, or hypertrophy was seen in several entities, including congenital hypertrophy of the retinal pigment epithelium, ora serrata pearl, TCD, cystic retinal tuft, meridional fold, lattice, and cobblestone degenerations. Hyporeflective intraretinal spaces, indicating cystoid or schitic fluid, were seen in ora serrata pearl, ora tooth, TCD, cystic retinal tuft, meridional fold, retinal hole, and typical degenerative senile retinoschisis. The vitreoretinal interface, which often consisted of lamellae-like structures of the condensed cortical vitreous near or adherent to the neural retina, appeared clearly in most peripheral findings, confirming its association with many low-risk and vision

  9. Raised intraocular pressure and recurrence of retinal detachment as complications of external retinal detachment surgery

    International Nuclear Information System (INIS)

    Jawwad, M.; Khan, B.; Shah, M.A.; Qayyum, I.; Aftab, M.; Qayyum, I.

    2015-01-01

    Patients with Rhegmatogenous retinal detachment may develop raised intraocular pressure and recurrence of retinal detachment when they undergo external retinal detachment surgery. The present study was conducted to determine the postoperative rise in intraocular pressure (IOP) and recurrence of retinal detachment. Methods: The present descriptive study was conducted at Eye department of Lady Reading Hospital, Peshawar on 25 patients of both genders from August 2012 to July 2014. Results: Of the 25 patients, 18 (72%) developed raised IOP in the immediate postoperative period; this figure decreased to 12 (48%) at one week. Following medical or surgical intervention in these 12 cases, there was only 1 (4%) case with mildly raised IOP at two weeks postoperative. Five (20%) cases developed recurrent retinal detachment which later resolved with treatment. There were no significant differences by age or gender. Conclusion: External Retinal Detachment Surgery raised intraocular pressure postoperatively and caused recurrence of retinal detachment. These complications were treated medically and surgically with resolution within two weeks. (author)

  10. Peripheral Retinal Vascular Patterns in Patients with Rhegmatogenous Retinal Detachment in Taiwan

    Science.gov (United States)

    Chen, San-Ni; Hwang, Jiunn-Feng; Wu, Wen-Chuan

    2016-01-01

    This is an observational study of fluorescein angiography (FA) in consecutive patients with rhegmatogenous retinal detachment (RRD) in Changhua Christian Hospital to investigate the peripheral retinal vascular patterns in those patients. All patients had their age, sex, axial length (AXL), and refraction status (RF) recorded. According to the findings in FA of the peripheral retina, the eyes were divided into 4 groups: in group 1, there was a ramified pattern of peripheral retinal vasculature with gradual tapering; in group 2, there was an abrupt ending of peripheral vasculature with peripheral non-perfusion; in group 3, there was a curving route of peripheral vasculature forming vascular arcades or anastomosis; and in group 4, the same as in group 3, but with one or more wedge-shaped avascular notches. Comparisons of age, sex, AXL, and RF, association of breaks with lattice degeneration and retinal non-perfusion, surgical procedures utilized, and mean numbers of operations were made among the four groups. Of the 73 eyes studied, there were 13 eyes (17.8%) in group 1, 3 eyes (4.1%) in group 2, 40 eyes (54.8%) in group 3 and 17 eyes (23.3%) in group 4. Significant differences in age, AXL and RF, and association of retinal breaks to non-perfusion were noted among the four groups. Patients in group 1 had older ages, while younger ages were noted in groups 3 and 4. Eyes in group 1 had the shortest average AXL and were least myopic in contrast to the eyes in groups 3 and 4. Association of retinal breaks and retinal non-perfusion was significantly higher in groups 2, 3 and 4 than in group 1. In conclusion, peripheral vascular anomalies are common in cases with RRD. Patients with peripheral non-perfusion tend to be younger, with longer axial length and have the breaks associated with retinal non-perfusion. PMID:26909812

  11. Patient pain and blood management in total hip and knee arthroplasty

    NARCIS (Netherlands)

    Thomassen, Bregje J.W.

    2014-01-01

    What is already known on this topic: Local infiltration analgesia in combination with a multimodal pain approach helps for adequate postoperative pain control. Blood saving alternatives should be implemented in the process of primary total hip and knee arthroplasties. The endpoint in patient

  12. Optical modulation of transgene expression in retinal pigment epithelium

    Science.gov (United States)

    Palanker, D.; Lavinsky, D.; Chalberg, T.; Mandel, Y.; Huie, P.; Dalal, R.; Marmor, M.

    2013-03-01

    Over a million people in US alone are visually impaired due to the neovascular form of age-related macular degeneration (AMD). The current treatment is monthly intravitreal injections of a protein which inhibits Vascular Endothelial Growth Factor, thereby slowing progression of the disease. The immense financial and logistical burden of millions of intravitreal injections signifies an urgent need to develop more long-lasting and cost-effective treatments for this and other retinal diseases. Viral transfection of ocular cells allows creation of a "biofactory" that secretes therapeutic proteins. This technique has been proven successful in non-human primates, and is now being evaluated in clinical trials for wet AMD. However, there is a critical need to down-regulate gene expression in the case of total resolution of retinal condition, or if patient has adverse reaction to the trans-gene products. The site for genetic therapy of AMD and many other retinal diseases is the retinal pigment epithelium (RPE). We developed and tested in pigmented rabbits, an optical method to down-regulate transgene expression in RPE following vector delivery, without retinal damage. Microsecond exposures produced by a rapidly scanning laser vaporize melanosomes and destroy a predetermined fraction of the RPE cells selectively. RPE continuity is restored within days by migration and proliferation of adjacent RPE, but since the transgene is not integrated into the nucleus it is not replicated. Thus, the decrease in transgene expression can be precisely determined by the laser pattern density and further reduced by repeated treatment without affecting retinal structure and function.

  13. Racial differences in retinal vessel geometric characteristics: a multiethnic study in healthy Asians.

    Science.gov (United States)

    Li, Xiang; Wong, Wan Ling; Cheung, Carol Yim-Lui; Cheng, Ching-Yu; Ikram, Mohammad Kamran; Li, Jialiang; Chia, Kee Seng; Wong, Tien Yin

    2013-05-01

    To investigate potential racial/ethnic differences in retinal vascular geometric parameters in a multiethnic Asian population (Chinese, Malay, and Indian) free of clinical diseases. A series of retinal vascular parameters were measured from retinal photographs using a computer-assisted program following a standardized protocol. Healthy participants were defined as nonsmokers, the absence of diabetes mellitus, uncontrolled hypertension, obesity, stroke, heart disease, glaucoma, and retinopathy. THERE WERE SIGNIFICANT DIFFERENCES IN MEASUREMENTS OF RETINAL VASCULAR CALIBER, TORTUOSITY, AND FRACTAL DIMENSION AMONG THE THREE ETHNIC GROUPS. IN MULTIPLE LINEAR REGRESSION MODEL CONTROLLING FOR AGE, SEX, BODY MASS INDEX, SYSTOLIC BLOOD PRESSURE, CHOLESTEROL, AND GLUCOSE LEVELS, INDIANS HAD THE LARGEST ARTERIOLAR AND VENULAR CALIBERS (ARTERIOLES [SE]: 158.94 μm [1.00]; venules: 228.26 μm [1.53]), followed by Malays (arterioles: 138.31 μm [0.74]; venules: 204.26 μm [1.13]), and then Chinese (arterioles: 131.20 μm [0.84]; venules: 195.09 μm [1.28]). Chinese had the largest arteriolar and venular tortuosity (arterioles [× $${10}^{5}$$]: 7.20 [0.08] VENULES [ $${10}^{5}$$]: 9.09 [0.10]), and venular fractal dimension (1.244 [0.003]). There were no statistically significant differences in other retinal vascular parameters after correcting multiple comparisons by the method of modified false discovery rate. We found that among ethnic groups composed of healthy Chinese, Malay, and Indians, there were statistically significant differences in several retinal parameters. There exist racial influences in retinal vascular parameters and other yet unknown or unmeasured environmental factor or lifestyle habits and genetic variations not related to race that may also contribute to these differences.

  14. Investigation of retinal morphology alterations using spectral domain optical coherence tomography in a mouse model of retinal branch and central retinal vein occlusion.

    Directory of Open Access Journals (Sweden)

    Andreas Ebneter

    Full Text Available Retinal vein occlusion is a leading cause of visual impairment. Experimental models of this condition based on laser photocoagulation of retinal veins have been described and extensively exploited in mammals and larger rodents such as the rat. However, few reports exist on the use of this paradigm in the mouse. The objective of this study was to investigate a model of branch and central retinal vein occlusion in the mouse and characterize in vivo longitudinal retinal morphology alterations using spectral domain optical coherence tomography. Retinal veins were experimentally occluded using laser photocoagulation after intravenous application of Rose Bengal, a photo-activator dye enhancing thrombus formation. Depending on the number of veins occluded, variable amounts of capillary dropout were seen on fluorescein angiography. Vascular endothelial growth factor levels were markedly elevated early and peaked at day one. Retinal thickness measurements with spectral domain optical coherence tomography showed significant swelling (p<0.001 compared to baseline, followed by gradual thinning plateauing two weeks after the experimental intervention (p<0.001. Histological findings at day seven correlated with spectral domain optical coherence tomography imaging. The inner layers were predominantly affected by degeneration with the outer nuclear layer and the photoreceptor outer segments largely preserved. The application of this retinal vein occlusion model in the mouse carries several advantages over its use in other larger species, such as access to a vast range of genetically modified animals. Retinal changes after experimental retinal vein occlusion in this mouse model can be non-invasively quantified by spectral domain optical coherence tomography, and may be used to monitor effects of potential therapeutic interventions.

  15. Modern Diagnostic Techniques for the Assessment of Ocular Blood Flow in Myopia: Current State of Knowledge.

    Science.gov (United States)

    Grudzińska, Ewa; Modrzejewska, Monika

    2018-01-01

    Myopia is the most common refractive error and the subject of interest of various studies assessing ocular blood flow. Increasing refractive error and axial elongation of the eye result in the stretching and thinning of the scleral, choroid, and retinal tissues and the decrease in retinal vessel diameter, disturbing ocular blood flow. Local and systemic factors known to change ocular blood flow include glaucoma, medications and fluctuations in intraocular pressure, and metabolic parameters. Techniques and tools assessing ocular blood flow include, among others, laser Doppler flowmetry (LDF), retinal function imager (RFI), laser speckle contrast imaging (LSCI), magnetic resonance imaging (MRI), optical coherence tomography angiography (OCTA), pulsatile ocular blood flowmeter (POBF), fundus pulsation amplitude (FPA), colour Doppler imaging (CDI), and Doppler optical coherence tomography (DOCT). Many researchers consistently reported lower blood flow parameters in myopic eyes regardless of the used diagnostic method. It is unclear whether this is a primary change that causes secondary thinning of ocular tissues or quite the opposite; that is, the mechanical stretching of the eye wall reduces its thickness and causes a secondary lower demand of tissues for oxygen. This paper presents a review of studies assessing ocular blood flow in myopes.

  16. Retinal Imaging and Image Analysis

    Science.gov (United States)

    Abràmoff, Michael D.; Garvin, Mona K.; Sonka, Milan

    2011-01-01

    Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships. PMID:22275207

  17. Extracellular space, blood volume, and the early dumping syndrome after total gastrectomy

    Energy Technology Data Exchange (ETDEWEB)

    Miholic, J.; Reilmann, L.; Meyer, H.J.; Koerber, H.K.; Kotzerke, J.; Hecker, H. (Medzinische Hochschule Hannover (Germany, F.R.))

    1990-10-01

    Extracellular space and blood volume were measured using 82Br dilution and 51Cr-tagged erythrocytes in 24 tumor-free patients after total gastrectomy. Eleven of the patients suffered from early dumping. Age, blood volume, and extracellular space were significantly smaller in dumpers (P less than 0.05). The dumping score could be predicted by a multiple regression model considering blood volume per lean body mass and extracellular space (r = 0.637; P = 0.0039). Rapid (t1/2 less than 360 seconds) emptying of the gastric substitute, assessed using a 99Tc-labeled solid test meal, was significantly associated with dumping in addition to extracellular space and blood volume (r = 0.876; P = 0.0018). Both rapid emptying and a narrow extracellular space seem to contribute to the early dumping syndrome.

  18. [Peripheral retinal degenerations--treatment recommendations].

    Science.gov (United States)

    Joussen, A M; Kirchhof, B

    2004-10-01

    This report reviews the clinical appearance of degenerative diseases of the peripheral retina in relationship to the risk of developing a rhegmatogenous retinal detachment. We present recommendations for preventive treatment in eyes at increased risk of developing retinal detachment. Retinal degenerations are common lesions involving the peripheral retina but most of them are clinically insignificant. Lattice degeneration, degenerative retinoschisis, cystic retinal tufts, and very rarely zonular traction tufts can result in rhegmatogenous retinal detachment. Therefore, these lesions have been considered for prophylactic treatment; however, adequate studies have not been performed to date. Most of the peripheral retinal degenerations may not require treatment except in rare, high-risk situations. According to current knowledge there is no higher incidence of secondary pucker or other side effects after laser coagulation. Therefore, generous laser indication is recommended if risk factors apply.

  19. Rhegmatogenous retinal detachment and conventional surgical treatment.

    Science.gov (United States)

    Golubovic, M

    2013-01-01

    The aim of the paper was to present the efficacy and indications for application of conventional surgical treatment of retinal detachment by using external implants, that is,application of encircling band and buckle. This study comprised patients from the University Eye Clinic in Skopje. A total of 33 patients were diagnosed and surgically treated in the period between May 2010 and August 2011. Conventional surgery was applied in smaller number of patients whose changes of the vitreous body were manifested by detachment of posterior hyaloid membrane, syneresis, with appearance of a small number of pigment cells in the vitreous body and synchysis, and the very retina was with fresh detachment without folds or epiretinal changes (that is, PVR A grade). There were a larger number of patients with more distinct proliferative changes of the vitreous body and of the retina, grades PVR B to C1-C2, and who also underwent the same surgical approach. Routine ophthalmologic examinations were performed, including: determination of visual acuity by Snellen's optotypes, determination of eye pressure with Schiotz's tonometer, examination of anterior segment on biomicroscopy, indirect biomicroscopy of posterior eye segment (vitreous body and retina) and examination on biomicroscopy with Goldmann prism, B scan echography of the eyes before and after surgical treatment. Conventional treatment was used by external application of buckle or application of buckle and encircling band. In case of one break, radial buckle was applied and in case of multiple breaks in one quadrant limbus parallel buckle was applied. Besides buckle, encircling band was applied in patients with total or subtotal retinal detachment with already present distinct changes in the vitreous body (PVR B or C1-C2) and degenerative changes in the vitreous body. Breaks were closed with cryopexy. The results obtained have shown that male gender was predominant and that the disease was manifested in younger male adults

  20. Regorafenib-induced retinal and gastrointestinal hemorrhage in a metastatic colorectal cancer patient with liver dysfunction

    Science.gov (United States)

    Tsuchihashi, Kenji; Shimokawa, Hozumi; Takayoshi, Kotoe; Nio, Kenta; Aikawa, Tomomi; Matsushita, Yuzo; Wada, Iori; Arita, Shuji; Ariyama, Hiroshi; Kusaba, Hitoshi; Sonoda, Koh-Hei; Akashi, Koichi; Baba, Eishi

    2017-01-01

    Abstract Rationale: Regorafenib is effective for metastatic colorectal cancer but its toxicity such as hemorrhage should be considered. The safety of regorafenib for the patient with the liver disease is not known. Patient concerns: Seventy-one-year old man of colon cancer had myodesopsia and blood stool after 14 days from the initiation of regorafenib administration with 50% dose reduction due to liver dysfunction. Diagnoses: Fundus examination revealed hemorrhage of the retinal vein. Interventions: Regorafenib treatment was discontinued and observational therapy was pursued. Outcomes: Retinal and gastrointestinal hemorrhage resolved in 1 week. Lessons: Retinal hemorrhage should be considered as the differential diagnosis of myodesopsia in the patient treated by regorafenib. Safety and pharmacokinetic of continuous regorafenib administration for patients with liver dysfunction remains to be clarified. PMID:29049226

  1. Novel Retinal Lesion in Ebola Survivors, Sierra Leone, 2016.

    Science.gov (United States)

    Steptoe, Paul J; Scott, Janet T; Baxter, Julia M; Parkes, Craig K; Dwivedi, Rahul; Czanner, Gabriela; Vandy, Matthew J; Momorie, Fayiah; Fornah, Alimamy D; Komba, Patrick; Richards, Jade; Sahr, Foday; Beare, Nicholas A V; Semple, Malcolm G

    2017-07-01

    We conducted a case-control study in Freetown, Sierra Leone, to investigate ocular signs in Ebola virus disease (EVD) survivors. A total of 82 EVD survivors with ocular symptoms and 105 controls from asymptomatic civilian and military personnel and symptomatic eye clinic attendees underwent ophthalmic examination, including widefield retinal imaging. Snellen visual acuity was Ebola virus, permitting cataract surgery. A novel retinal lesion following the anatomic distribution of the optic nerve axons occurred in 14.6% (97.5% CI 7.1%-25.6%) of EVD survivors and no controls, suggesting neuronal transmission as a route of ocular entry.

  2. Quantitative measurement of total cerebral blood flow using 2D phase-contrast MRI and doppler ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Keum Soo; Choi, Sun Seob; Lee, Young Il [Dong-A Univ., College of Medicine, Busan (Korea, Republic of)

    2001-12-01

    To compare of quantitative measurement of the total cerebral blood flow using two-dimensional phase-contrast MR imaging and Doppler ultrasound. In 16 volunteers (mean age, 26 years; mean body weight, 66 kg) without abnormal medical histories, two-dimensional phase-contrast MR imaging was performed at the level of the C2-3 inter vertebral disc for flow measurement of the internal carotid arteries and the vertebral arteries. Volume flow measurements using Doppler ultrasound were also performed at the internal carotid arteries 2cm above the carotid bifurcation, and at the vertebral arteries at the level of the upper pole of the thyroid gland. Flows in the four vessels measured by the two methods were compared using Wilcoxon's correlation analysis and the median score. Total cerebral blood flows were calculated by summing these four vessel flows, and mean values for the 16 volunteers were calculated. Cerebral blood flows measured by 2-D phase-contrast MR imaging and Doppler ultrasounds were 233 and 239 ml/min in the right internal carotid artery, 250 and 248 ml/min in the left internal carotid artery, 62 and 56 ml/min in the right vertebral artery, and 83 and 68 ml/min in the left vertebral artery. Correlation coefficients of the blood flows determined by the two methods were 0.48, 0.54, 0.49, and 0.62 in each vessel, while total cerebral blood flows were 628{+-}68 (range, 517 to 779) ml/min and 612{+-}79 (range, 482 to 804)ml/min, respectively. Total cerebral blood flow was easily measured using 2-D phase-contrast MR imaging and Doppler ultrasound, and the two noninvasive methods can therefore be used clinically for the measurement of total cerebral blood flow.

  3. Tlx acts as a proangiogenic switch by regulating extracellular assembly of fibronectin matrices in retinal astrocytes.

    Science.gov (United States)

    Uemura, Akiyoshi; Kusuhara, Sentaro; Wiegand, Stanley J; Yu, Ruth T; Nishikawa, Shin-ichi

    2006-02-01

    In response to hypoxia, hypoxia-inducible factors act as the primary proangiogenic triggers by regulating transcription levels of target genes, including VEGF. However, little is known about the specific factors that control other components of the angiogenic process, particularly formation of matrix scaffolds that promote adhesion and migration of endothelial cells. We show that in the postnatal mouse retina, the orphan nuclear receptor tailless (Tlx) is strongly expressed in the proangiogenic astrocytes, which secrete VEGF and fibronectin. Tlx expression by retinal astrocytes is controlled by oxygen concentration and rapidly downregulated upon contact with blood vessels. In mice null for Tlx, retinal astrocytes maintain VEGF expression; however, the extracellular assembly of fibronectin matrices by astrocytes is severely impaired, leading to defective scaffold formation and a complete failure of normal retinal vascular development. This work identifies Tlx as an essential component of the molecular network involved in the hypoxia-inducible proangiogenic switch in retinal astrocytes.

  4. Retinal ischemic injury rescued by sodium 4-phenylbutyrate in a rat model.

    Science.gov (United States)

    Jeng, Yung-Yue; Lin, Nien-Ting; Chang, Pen-Heng; Huang, Yuan-Ping; Pang, Victor Fei; Liu, Chen-Hsuan; Lin, Chung-Tien

    2007-03-01

    Retinal ischemia is a common cause of visual impairment for humans and animals. Herein, the neuroprotective effects of phenylbutyrate (PBA) upon retinal ischemic injury were investigated using a rat model. Retinal ganglion cells (RGCs) were retrograde labeled with the fluorescent tracer fluorogold (FG) applied to the superior collicoli of test Sprague-Dawley rats. High intraocular pressure and retinal ischemia were induced seven days subsequent to such FG labeling. A dose of either 100 or 400 mg/kg PBA was administered intraperitoneally to test rats at two time points, namely 30 min prior to the induction of retinal ischemia and 1 h subsequent to the cessation of the procedure inducing retinal ischemia. The test-rat retinas were collected seven days subsequent to the induction of retinal ischemia, and densities of surviving RGCs were estimated by counting FG-labeled RGCs within the retina. Histological analysis revealed that ischemic injury caused the loss of retinal RGCs and a net decrease in retinal thickness. For PBA-treated groups, almost 100% of the RGCs were preserved by a pre-ischemia treatment with PBA (at a dose of either 100 or 400 mg/kg), while post-ischemia treatment of RGCs with PBA did not lead to the preservation of RGCs from ischemic injury by PBA as determined by the counting of whole-mount retinas. Pre-ischemia treatment of RGCs with PBA (at a dose of either 100 or 400 mg/kg) significantly reduced the level of ischemia-associated loss of thickness of the total retina, especially the inner retina, and the inner plexiform layer of retina. Besides, PBA treatment significantly reduced the ischemia-induced loss of cells in the ganglion-cell layer of the retina. Taken together, these results suggest that PBA demonstrates a marked neuroprotective effect upon high intraocular pressure-induced retinal ischemia when the PBA is administered prior to ischemia induction.

  5. Ocular neovascularization in eyes with a central retinal artery occlusion or a branch retinal artery occlusion

    Directory of Open Access Journals (Sweden)

    Mason lll JO

    2015-06-01

    Full Text Available John O Mason III,1,2 Shyam A Patel,1 Richard M Feist,1,2 Michael A Albert Jr,1,2 Carrie Huisingh,1 Gerald McGwin Jr,1,3 Martin L Thomley1,2 1Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, AL, USA; 2Retina Consultants of Alabama, Callahan Eye Foundation Hospital, Birmingham, AL, USA; 3Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA Purpose: To investigate the ocular neovascularization (ONV rate in eyes with a branch retinal artery occlusion (BRAO or a central retinal artery occlusion (CRAO, and to study factors that may influence the ONV rate secondary to CRAO.Methods: This was a retrospective case series of consecutive patients (286 total eyes: 83 CRAOs and 203 BRAOs who were diagnosed with a retinal artery occlusion from 1998 to 2013 at the Retina Consultants of Alabama and University of Alabama at Birmingham, Birmingham, AL, USA. Generalized estimating equations were used to evaluate the association between hypothesized risk factors and ONV development.Results: Twelve (14.5% of the 83 eyes with a CRAO developed ONV. Eleven of 12 eyes (91.7% had iris neovascularization, ten of 12 eyes (83.3% had neovascular glaucoma, and two of 12 eyes (16.7% had neovascularization of the optic disc. The average time for ONV development secondary to CRAO was 30.7 days, ranging from the date of presentation to 137 days. Only two (<1.0% of the 203 eyes with a BRAO developed iris neovascularization. Diabetes mellitus type 2 was a risk factor for ONV development following a CRAO with an adjusted odds ratio of 5.2 (95% confidence interval: 1.4–19.8 (P=0.02.Conclusion: ONV is an important complication of CRAO and is a less-frequent complication of BRAO. Patients with a CRAO, especially those with diabetes mellitus type 2, should be closely monitored for the first 6 months for ONV. Keywords: neovascularization, neovascular glaucoma, retinal artery occlusion, central

  6. Risk factor profile in retinal detachment

    Directory of Open Access Journals (Sweden)

    Azad Raj

    1988-01-01

    Full Text Available 150 cases of retinal detachment comprising 50 patients each of bilateral retinal detachment, unilateral retinal detachment without any retinal lesions in the fellow eve and unilateral retinal detachment with retinal lesions in the fellow eye were studied and the various associated risk factors were statistically analysed. The findings are discussed in relation to their aetiological and prognostic significance in the different types of retinal detachment. Based on these observations certain guidelines are offered which may be of value in decision making, in prophylactic detachment surgery. Tractional breaks in the superior temporal quadrant especially when symptomatic. mandate prophylactic treatment. Urgency is enhanced it′ the patient is aphakic. Associated myopia adds to the urgency. The higher incidence of initial right e′ e involvement in all groups suggests a vascular original possibly ischaemic.

  7. Cytomegalovirus retinitis after central retinal vein occlusion in a patient on systemic immunosuppression: does venooclusive disease predispose to cytomegalovirus retinitis in patients already at risk?

    Directory of Open Access Journals (Sweden)

    Welling JD

    2012-04-01

    Full Text Available John D Welling, Ahmad B Tarabishy, John ChristoforidisDepartment of Ophthalmology, Havener Eye Institute, Ohio State University, Columbus, OH, USAAbstract: Cytomegalovirus (CMV retinitis remains the most common opportunistic ocular infection in immunocompromised patients. Patients with immunocompromising diseases, such as acquired immunodeficiency syndrome, inherited immunodeficiency states, malignancies, and those on systemic immunosuppressive therapy, are known to be at risk. Recently, it has been suggested that patients undergoing intravitreal injection of immunosuppressive agents may also be predisposed. One previous case report speculated that there may be an additional risk for CMV retinitis in acquired immunodeficiency syndrome patients with venoocclusive disease. This case study presents a case of CMV retinitis following central retinal vein occlusion in a patient on systemic immunosuppressants.Keywords: cytomegalovirus retinitis, central retinal vein occlusion, immunosuppression, solid organ transplant, venous stasis, risk factor

  8. WIDEFIELD SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY IMAGING OF PERIPHERAL ROUND RETINAL HOLES WITH OR WITHOUT RETINAL DETACHMENT.

    Science.gov (United States)

    Casswell, Edward J; Abou Ltaif, Sleiman; Carr, Thomas; Keane, Pearse A; Charteris, David G; Wickham, Louisa

    2018-03-02

    To describe the widefield spectral-domain optical coherence tomography features of peripheral round retinal holes, with or without associated retinal detachment (RD). Retrospective, observational study of 28 eyes with peripheral round retinal holes, with and without RD. Patients underwent imaging with a widefield 50-degree spectral-domain optical coherence tomography (Heidelberg Engineering, Germany) and Optos ultra-widefield imaging systems (Optos, United Kingdom). Vitreous attachment at the site of the retinal hole was detected in 27/28 (96.4%) cases. Cases were split into three groups: RHs with RD (n = 12); RHs with subretinal fluid (n = 5), and flat RHs (n = 11), with minimal or no subretinal fluid. 91.6% retinal holes associated with subretinal fluid or RD had vitreous attachment at the site of the hole. Eighty percent had vitreous attachment at both edges of the retinal hole, in a U-shape configuration, which appeared to exert traction. By contrast, flat retinal holes had visible vitreous attachment only at one edge of the retinal hole in 45.4%. Vitreous attachment was commonly seen at the site of round retinal holes. Vitreous attachment at both edges of the retinal hole in a U-shape configuration was more commonly seen at holes associated with subretinal fluid or RD.

  9. Automatic detection of retinal anatomy to assist diabetic retinopathy screening

    Science.gov (United States)

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

    2007-01-01

    Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening.

  10. Automatic detection of retinal anatomy to assist diabetic retinopathy screening

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Alan D [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Goatman, Keith A [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom); Philip, Sam [Grampian Diabetes Retinal Screening Programme, Woolmanhill Hospital, Aberdeen, AB25 1LD (United Kingdom); Olson, John A [Grampian Diabetes Retinal Screening Programme, Woolmanhill Hospital, Aberdeen, AB25 1LD (United Kingdom); Sharp, Peter F [Biomedical Physics, University of Aberdeen, Aberdeen, AB25 2ZD (United Kingdom)

    2007-01-21

    Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening.

  11. Automatic detection of retinal anatomy to assist diabetic retinopathy screening

    International Nuclear Information System (INIS)

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

    2007-01-01

    Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening

  12. Automatic detection of retinal anatomy to assist diabetic retinopathy screening.

    Science.gov (United States)

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

    2007-01-21

    Screening programmes for diabetic retinopathy are being introduced in the United Kingdom and elsewhere. These require large numbers of retinal images to be manually graded for the presence of disease. Automation of image grading would have a number of benefits. However, an important prerequisite for automation is the accurate location of the main anatomical features in the image, notably the optic disc and the fovea. The locations of these features are necessary so that lesion significance, image field of view and image clarity can be assessed. This paper describes methods for the robust location of the optic disc and fovea. The elliptical form of the major retinal blood vessels is used to obtain approximate locations, which are refined based on the circular edge of the optic disc and the local darkening at the fovea. The methods have been tested on 1056 sequential images from a retinal screening programme. Positional accuracy was better than 0.5 of a disc diameter in 98.4% of cases for optic disc location, and in 96.5% of cases for fovea location. The methods are sufficiently accurate to form an important and effective component of an automated image grading system for diabetic retinopathy screening.

  13. Use of tranexamic acid in primary total knee replacement: effects on perioperative blood loss.

    Science.gov (United States)

    Volquind, Daniel; Zardo, Remi Antônio; Winkler, Bruno Costamilan; Londero, Bruno Bertagnolli; Zanelatto, Natália; Leichtweis, Gisele Perondi

    2016-01-01

    The use of tranexamic acid in primary total knee replacement surgeries has been the subject of constant study. The strategies to reduce bleeding are aimed at reducing the need for blood transfusion due to the risks involved. In this study we evaluated the use of tranexamic acid in reducing bleeding, need for blood transfusion, and prevalence of postoperative deep vein thrombosis in primary total knee replacement. 62 patients undergoing primary total knee replacement were enrolled in the study, from June 2012 to May 2013, and randomized to receive a single dose of 2.5g of intravenous tranexamic acid (Group TA) or saline (Group GP), 5min before opening the pneumatic tourniquet, respectively. Hemoglobin, hematocrit, and blood loss were recorded 24h after surgery. Deep vein thrombosis was investigated during patient's hospitalization and 15 and 30 days after surgery in review visits. There was no demographic difference between groups. Group TA had 13.89% decreased hematocrit (p=0.925) compared to placebo. Group TA had a decrease of 12.28% (p=0.898) in hemoglobin compared to Group GP. Group TA had a mean decrease of 187.35mL in blood loss (25.32%) compared to group GP (p=0.027). The number of blood transfusions was higher in Group GP (p=0.078). Thromboembolic events were not seen in this study. Tranexamic acid reduced postoperative bleeding without promoting thromboembolic events. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  14. Agmatine protects retinal ganglion cells from hypoxia-induced apoptosis in transformed rat retinal ganglion cell line

    Directory of Open Access Journals (Sweden)

    Kim Chan

    2007-10-01

    Full Text Available Abstract Background Agmatine is an endogenous polyamine formed by the decarboxylation of L-arginine. We investigated the protective effects of agmatine against hypoxia-induced apoptosis of immortalized rat retinal ganglion cells (RGC-5. RGC-5 cells were cultured in a closed hypoxic chamber (5% O2 with or without agmatine. Cell viability was determined by lactate dehydrogenase (LDH assay and apoptosis was examined by annexin V and caspase-3 assays. Expression and phosphorylation of mitogen-activated protein kinases (MAPKs; JNK, ERK p44/42, and p38 and nuclear factor-kappa B (NF-κB were investigated by Western immunoblot analysis. The effects of agmatine were compared to those of brain-derived neurotrophic factor (BDNF, a well-known protective neurotrophin for retinal ganglion cells. Results After 48 hours of hypoxic culture, the LDH assay showed 52.3% cell loss, which was reduced to 25.6% and 30.1% when agmatine and BDNF were administered, respectively. This observed cell loss was due to apoptotic cell death, as established by annexin V and caspase-3 assays. Although total expression of MAPKs and NF-κB was not influenced by hypoxic injury, phosphorylation of these two proteins was increased. Agmatine reduced phosphorylation of JNK and NF-κB, while BDNF suppressed phosphorylation of ERK and p38. Conclusion Our results show that agmatine has neuroprotective effects against hypoxia-induced retinal ganglion cell damage in RGC-5 cells and that its effects may act through the JNK and NF-κB signaling pathways. Our data suggest that agmatine may lead to a novel therapeutic strategy to reduce retinal ganglion cell injury related to hypoxia.

  15. Agmatine protects retinal ganglion cells from hypoxia-induced apoptosis in transformed rat retinal ganglion cell line

    Science.gov (United States)

    Hong, Samin; Lee, Jong Eun; Kim, Chan Yun; Seong, Gong Je

    2007-01-01

    Background Agmatine is an endogenous polyamine formed by the decarboxylation of L-arginine. We investigated the protective effects of agmatine against hypoxia-induced apoptosis of immortalized rat retinal ganglion cells (RGC-5). RGC-5 cells were cultured in a closed hypoxic chamber (5% O2) with or without agmatine. Cell viability was determined by lactate dehydrogenase (LDH) assay and apoptosis was examined by annexin V and caspase-3 assays. Expression and phosphorylation of mitogen-activated protein kinases (MAPKs; JNK, ERK p44/42, and p38) and nuclear factor-kappa B (NF-κB) were investigated by Western immunoblot analysis. The effects of agmatine were compared to those of brain-derived neurotrophic factor (BDNF), a well-known protective neurotrophin for retinal ganglion cells. Results After 48 hours of hypoxic culture, the LDH assay showed 52.3% cell loss, which was reduced to 25.6% and 30.1% when agmatine and BDNF were administered, respectively. This observed cell loss was due to apoptotic cell death, as established by annexin V and caspase-3 assays. Although total expression of MAPKs and NF-κB was not influenced by hypoxic injury, phosphorylation of these two proteins was increased. Agmatine reduced phosphorylation of JNK and NF-κB, while BDNF suppressed phosphorylation of ERK and p38. Conclusion Our results show that agmatine has neuroprotective effects against hypoxia-induced retinal ganglion cell damage in RGC-5 cells and that its effects may act through the JNK and NF-κB signaling pathways. Our data suggest that agmatine may lead to a novel therapeutic strategy to reduce retinal ganglion cell injury related to hypoxia. PMID:17908330

  16. Quantifying Blood Loss and Transfusion Risk After Primary vs Conversion Total Hip Arthroplasty.

    Science.gov (United States)

    Newman, Jared M; Webb, Matthew R; Klika, Alison K; Murray, Trevor G; Barsoum, Wael K; Higuera, Carlos A

    2017-06-01

    Primary total hip arthroplasty (THA) and conversion THA may result in substantial blood loss, sometimes necessitating transfusion. Despite the complexities of the latter, both are grouped in the same category for quality assessment and reimbursement. This study's purpose was to compare both blood loss and transfusion risk in primary and conversion THA and identify their associated predictors. A total of 1616 patients who underwent primary and conversion THA at a single hospital from 2009-2013 were reviewed (primary THA = 1575; conversion THA = 41). Demographics, comorbidities, and perioperative data were collected from electronic records. Blood loss was calculated using a validated method. Transfusion triggers were based on standardized criteria. Separate multivariable regression models for blood loss and transfusion were performed. Conversion THA patients were younger (P = .002), had lower age-adjusted Charlson scores (P = .006), longer surgeries (P quantified in the present study and showed consistent results between the 2 metrics. The differences between these procedures should be addressed during quality assurance because conversion THA is associated with higher resource utilization, which is important in the allocation of resources and tiered reimbursement strategies. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Retinal detachment following endophthalmitis.

    Science.gov (United States)

    Nelsen, P T; Marcus, D A; Bovino, J A

    1985-08-01

    Fifty-five consecutive patients with a clinical diagnosis of bacterial endophthalmitis were reviewed. All patients were treated with systemic, periocular, topical, and intravitreal antibiotics. In addition, 33 of the patients underwent a pars plana vitrectomy. Nine retinal detachments occurred within six months of initial diagnosis. The higher frequency of retinal detachment in the vitrectomy group (21%) as compared to those patients managed without vitrectomy (9%) may be explained by a combination of surgical complications and the increased severity of endophthalmitis in the vitrectomy group. The two patients who developed retinal detachment during vitrectomy surgery rapidly progressed to no light perception. Conversely, the repair of retinal detachments diagnosed postoperatively had a good prognosis.

  18. Effect of pharmacologically induced retinal degeneration on retinal autofluorescence lifetimes in mice.

    Science.gov (United States)

    Dysli, Chantal; Dysli, Muriel; Zinkernagel, Martin S; Enzmann, Volker

    2016-12-01

    Fluorescence lifetime imaging ophthalmoscopy (FLIO) was used to investigate retinal autofluorescence lifetimes in mouse models of pharmacologically induced retinal degeneration over time. Sodium iodate (NaIO 3 , 35 mg/kg intravenously) was used to induce retinal pigment epithelium (RPE) degeneration with subsequent loss of photoreceptors (PR) whereas N-methyl-N-nitrosourea (MNU, 45 mg/kg intraperitoneally) was employed for degeneration of the photoreceptor cell layer alone. All mice were measured at day 3, 7, 14, and 28 after the respective injection of NaIO 3 , MNU or NaCl (control). Fluorescence lifetime imaging was performed using a fluorescence lifetime imaging ophthalmoscope (Heidelberg Engineering, Heidelberg, Germany). Fluorescence was excited at 473 nm and fluorescence lifetimes were measured in a short and a long spectral channel (498-560 nm and 560-720 nm). Corresponding optical coherence tomography (OCT) images were consecutively acquired and histology was performed at the end of the experiments. Segmentation of OCT images and histology verified the cell type-specific degeneration process over time. Retinal autofluorescence lifetimes increased from day 3 to day 28 in mice after NaIO 3 treatment. Finally, at day 28, fluorescence lifetimes were prolonged by 8% in the short and 61% in the long spectral channel compared to control animals (p = 0.21 and p = 0.004, respectively). In mice after MNU treatment, the mean retinal autofluorescence lifetimes were already decreased at day 3 and retinal lifetimes were finally shortened by 27% in the short and 51% in the long spectral channel at day 28 (p = 0.0028). In conclusion, degeneration of the RPE with subsequent photoreceptor degeneration by NaIO 3 lead to longer mean fluorescence lifetimes of the retina compared to control mice, whereas during specific degeneration of the photoreceptor layer induced by MNU shorter lifetimes were measured. Therefore, short retinal fluorescence lifetimes may originate

  19. Peripheral Retinal Vascular Patterns in Patients with Rhegmatogenous Retinal Detachment in Taiwan.

    Directory of Open Access Journals (Sweden)

    San-Ni Chen

    Full Text Available This is an observational study of fluorescein angiography (FA in consecutive patients with rhegmatogenous retinal detachment (RRD in Changhua Christian Hospital to investigate the peripheral retinal vascular patterns in those patients. All patients had their age, sex, axial length (AXL, and refraction status (RF recorded. According to the findings in FA of the peripheral retina, the eyes were divided into 4 groups: in group 1, there was a ramified pattern of peripheral retinal vasculature with gradual tapering; in group 2, there was an abrupt ending of peripheral vasculature with peripheral non-perfusion; in group 3, there was a curving route of peripheral vasculature forming vascular arcades or anastomosis; and in group 4, the same as in group 3, but with one or more wedge-shaped avascular notches. Comparisons of age, sex, AXL, and RF, association of breaks with lattice degeneration and retinal non-perfusion, surgical procedures utilized, and mean numbers of operations were made among the four groups. Of the 73 eyes studied, there were 13 eyes (17.8% in group 1, 3 eyes (4.1% in group 2, 40 eyes (54.8% in group 3 and 17 eyes (23.3% in group 4. Significant differences in age, AXL and RF, and association of retinal breaks to non-perfusion were noted among the four groups. Patients in group 1 had older ages, while younger ages were noted in groups 3 and 4. Eyes in group 1 had the shortest average AXL and were least myopic in contrast to the eyes in groups 3 and 4. Association of retinal breaks and retinal non-perfusion was significantly higher in groups 2, 3 and 4 than in group 1. In conclusion, peripheral vascular anomalies are common in cases with RRD. Patients with peripheral non-perfusion tend to be younger, with longer axial length and have the breaks associated with retinal non-perfusion.

  20. Advances in Retinal Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Andrea S Viczian

    2013-01-01

    Full Text Available Tremendous progress has been made in recent years to generate retinal cells from pluripotent cell sources. These advances provide hope for those suffering from blindness due to lost retinal cells. Understanding the intrinsic genetic network in model organisms, like fly and frog, has led to a better understanding of the extrinsic signaling pathways necessary for retinal progenitor cell formation in mouse and human cell cultures. This review focuses on the culture methods used by different groups, which has culminated in the generation of laminated retinal tissue from both embryonic and induced pluripotent cells. The review also briefly describes advances made in transplantation studies using donor retinal progenitor and cultured retinal cells.

  1. Regorafenib-induced retinal and gastrointestinal hemorrhage in a metastatic colorectal cancer patient with liver dysfunction: A case report.

    Science.gov (United States)

    Tsuchihashi, Kenji; Shimokawa, Hozumi; Takayoshi, Kotoe; Nio, Kenta; Aikawa, Tomomi; Matsushita, Yuzo; Wada, Iori; Arita, Shuji; Ariyama, Hiroshi; Kusaba, Hitoshi; Sonoda, Koh-Hei; Akashi, Koichi; Baba, Eishi

    2017-10-01

    Regorafenib is effective for metastatic colorectal cancer but its toxicity such as hemorrhage should be considered. The safety of regorafenib for the patient with the liver disease is not known. Seventy-one-year old man of colon cancer had myodesopsia and blood stool after 14 days from the initiation of regorafenib administration with 50% dose reduction due to liver dysfunction. Fundus examination revealed hemorrhage of the retinal vein. Regorafenib treatment was discontinued and observational therapy was pursued. Retinal and gastrointestinal hemorrhage resolved in 1 week. Retinal hemorrhage should be considered as the differential diagnosis of myodesopsia in the patient treated by regorafenib. Safety and pharmacokinetic of continuous regorafenib administration for patients with liver dysfunction remains to be clarified.

  2. Sector retinitis pigmentosa.

    Science.gov (United States)

    Van Woerkom, Craig; Ferrucci, Steven

    2005-05-01

    Retinitis pigmentosa (RP) is one of the most common hereditary retinal dystrophies and causes of visual impairment affecting all age groups. The reported incidence varies, but is considered to be between 1 in 3,000 to 1 in 7,000. Sector retinitis pigmentosa is an atypical form of RP that is characterized by regionalized areas of bone spicule pigmentation, usually in the inferior quadrants of the retina. A 57-year-old Hispanic man with a history of previously diagnosed retinitis pigmentosa came to the clinic with a longstanding symptom of decreased vision at night. Bone spicule pigmentation was found in the nasal and inferior quadrants in each eye. He demonstrated superior and temporal visual-field loss corresponding to the areas of the affected retina. Clinical measurements of visual-field loss, best-corrected visual acuity, and ophthalmoscopic appearance have remained stable during the five years the patient has been followed. Sector retinitis pigmentosa is an atypical form of RP that is characterized by bilateral pigmentary retinopathy, usually isolated to the inferior quadrants. The remainder of the retina appears clinically normal, although studies have found functional abnormalities in these areas as well. Sector RP is generally considered a stationary to slowly progressive disease, with subnormal electro-retinogram findings and visual-field defects corresponding to the involved retinal sectors. Management of RP is very difficult because there are no proven methods of treatment. Studies have shown 15,000 IU of vitamin A palmitate per day may slow the progression, though this result is controversial. Low vision rehabilitation, long wavelength pass filters, and pedigree counseling remain the mainstay of management.

  3. Total Artificial Heart Implantation Blood Pressure Management as Resolving Treatment for Massive Hemolysis following Total Artificial Heart Implantation.

    Science.gov (United States)

    Ghodsizad, Ali; Koerner, Michael M; El-Banayosy, A; Zeriouh, Mohamed; Ruhparwar, Arjang; Loebe, Matthias

    2016-10-21

    The SynCardia Total Artificial Heart (TAH) has been used for patients with biventricular failure, who cannot be managed with implantation of a left ventricular (LV) assist device. Following TAH implantation, our patient developed severe hemolysis, which could only be managed successfully by aggressive blood pressure control [Ohashi 2003; Nakata 1998].

  4. Cone dysfunctions in retinitis pigmentosa with retinal nerve fiber layer thickening.

    Science.gov (United States)

    Sobacı, Güngör; Ozge, Gökhan; Gündoğan, Fatih Ç

    2012-01-01

    To investigate whether or not thicker retinal nerve fiber layer (RNFL) in retinitis pigmentosa (RP) patients relates to functional abnormalities of the photoreceptors. Optical coherence tomography-based RNFL thickness was measured by Stratus-3™ (Zeiss, Basel, Switzerland) optical coherence tomography and electroretinogram (ERG) recordings made using the RETI-port(®) system (Roland, Wiesbaden, Germany) in 27 patients with retinitis pigmentosa and in 30 healthy subjects. Photopic ERG b-wave amplitude, cone ERG b-wave latency, 30 Hz flicker amplitude, and 30 Hz flicker latency had significant correlations to the RNFL-temporal (r = -0.55, P = 0.004, r = 0.68, P = 0.001, r = -0.65, P = 0.001, and r = -0.52, P = 0.007, respectively). Eyes with thicker RNFL (ten eyes) differed significantly from those with thinner RNFL (eight eyes) regarding cone ERG b-wave latency values only (P = 0.001). Thicker RNFL in patients with retinitis pigmentosa may be associated with functional abnormality of the cone system.

  5. Vessel Segmentation in Retinal Images Using Multi-scale Line Operator and K-Means Clustering.

    Science.gov (United States)

    Saffarzadeh, Vahid Mohammadi; Osareh, Alireza; Shadgar, Bita

    2014-04-01

    Detecting blood vessels is a vital task in retinal image analysis. The task is more challenging with the presence of bright and dark lesions in retinal images. Here, a method is proposed to detect vessels in both normal and abnormal retinal fundus images based on their linear features. First, the negative impact of bright lesions is reduced by using K-means segmentation in a perceptive space. Then, a multi-scale line operator is utilized to detect vessels while ignoring some of the dark lesions, which have intensity structures different from the line-shaped vessels in the retina. The proposed algorithm is tested on two publicly available STARE and DRIVE databases. The performance of the method is measured by calculating the area under the receiver operating characteristic curve and the segmentation accuracy. The proposed method achieves 0.9483 and 0.9387 localization accuracy against STARE and DRIVE respectively.

  6. Flow patterns on spectral-domain optical coherence tomography reveal flow directions at retinal vessel bifurcations

    DEFF Research Database (Denmark)

    Willerslev, Anne; Li, Xiao Q; Munch, Inger C

    2014-01-01

    PURPOSE: To study intravascular characteristics of flowing blood in retinal vessels using spectral-domain optical coherence tomography (SD-OCT). METHODS: Examination of selected arterial bifurcations and venous sites of confluence in 25 healthy 11-year-old children recruited as an ad hoc subsample...

  7. Isolation of Microarray-Grade Total RNA, MicroRNA, and DNA from a Single PAXgene Blood RNA Tube

    DEFF Research Database (Denmark)

    Kruhøffer, Mogens; Andersen, Lars Dyrskjøt; Voss, Thorsten

    2007-01-01

    We have developed a procedure for isolation of microRNA and genomic DNA in addition to total RNA from whole blood stabilized in PAXgene Blood RNA tubes. The procedure is based on automatic extraction on a BioRobot MDx and includes isolation of DNA from a fraction of the stabilized blood...... and recovery of small RNA species that are otherwise lost. The procedure presented here is suitable for large-scale experiments and is amenable to further automation. Procured total RNA and DNA was tested using Affymetrix Expression and single-nucleotide polymorphism GeneChips, respectively, and isolated micro......RNA was tested using spotted locked nucleic acid-based microarrays. We conclude that the yield and quality of total RNA, microRNA, and DNA from a single PAXgene blood RNA tube is sufficient for downstream microarray analysis....

  8. Retinal thickness as a marker of disease progression in longitudinal observation of patients with Wolfram syndrome.

    Science.gov (United States)

    Zmyslowska, Agnieszka; Fendler, Wojciech; Waszczykowska, Arleta; Niwald, Anna; Borowiec, Maciej; Jurowski, Piotr; Mlynarski, Wojciech

    2017-11-01

    Wolfram syndrome (WFS) is a recessively inherited monogenic form of diabetes coexisting with optic atrophy and neurodegenerative disorders with no currently recognized markers of disease progression. The aim of the study was to evaluate retinal parameters by using optical coherence tomography (OCT) in WFS patients after 2 years of follow-up and analysis of the parameters in relation to visual acuity. OCT parameters and visual acuity were measured in 12 WFS patients and 31 individuals with type 1 diabetes. Total thickness of the retinal nerve fiber layer (RNFL), average retinal thickness and total retinal volume decreased in comparison with previous OCT examination. Significant decreases were noted for RNFL (average difference -17.92 µm 95% CI -30.74 to -0.10; p = 0.0157), macular average thickness (average difference -5.38 µm 95% CI -10.63 to -2.36; p = 0.0067) and total retinal volume (average difference -0.15 mm 3 95% CI -0.30 to -0.07; p = 0.0070). Central thickness remained unchanged (average difference 1.5 µm 95% CI -7.61 to 10.61; p = 0.71). Visual acuity of WFS patients showed a strong negative correlation with diabetes duration (R = -0.82; p = 0.0010). After division of WFS patients into two groups (with low-vision and blind patients), all OCT parameters except for the RNFL value were lower in blind WFS patients. OCT measures structural parameters and can precede visual acuity loss. The OCT study in WFS patients should be performed longitudinally, and serial retinal examinations may be helpful as a potential end point for future clinical trials.

  9. SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY REVEALS INTERNAL LIMITING MEMBRANE PEELING ALTERS DEEP RETINAL VASCULATURE.

    Science.gov (United States)

    Michalewska, Zofia; Nawrocki, Jerzy

    2018-04-30

    To describe morphology of retinal and choroidal vessels in swept-source optical coherence tomography angiography before and after vitrectomy with the temporal inverted internal limiting membrane (ILM) flap technique for full-thickness macular holes. Prospective, observational study of 36 eyes of 33 patients with full-thickness macular holes swept-source optical coherence tomography angiography was performed in patients before and 1 month after vitrectomy. Vitrectomy with the temporal inverted ILM flap technique was performed. In this method, ILM is peeled only at one side of the fovea. An ILM flap is created to cover the macular hole. Comparison of retina vasculature in the areas of ILM peeling vs. no ILM peeling at 1 and 3 months after successful vitrectomy was performed. The study demonstrated lower density of vessels in the deep retinal plexus in the area where ILM was peeled as compared to the rest of the fovea. Visual acuity and central retinal thickness 1 month after surgery correlates with fovea avascular zone diameter in deep retinal layers at the same time point (P = 0.001). This study confirmed that ILM peeling might alter blood flow in deep retinal vessels below the peeling area in the early postoperative period. The area of the fovea avascular zone corresponds to functional results at the same time point.

  10. Evaluation of Blood Hemodynamics in Vascular Grafts after Total Arterial Coronary Revascularization

    Directory of Open Access Journals (Sweden)

    Ahmad Ali Amirghofran

    2016-07-01

    Full Text Available Arterial grafting has increasingly been advocated for the treatment of coronary artery disease in an attempt to improve the long-term results. In the quest to perform routine total arterial revascularization, composite Y graft methods are gaining popularity. The aim of our study was to evaluate whether blood flow in the left internal thoracic artery can provide sufficient perfusion to the entire cardiac muscle per se. Twenty patients with severe coronary artery stenosis who underwent complete arterial coronary revascularization using a composite graft entered our study. Blood flow in thoracic trunk was evaluated in three phases: cross-clamp on, cross-clamp off, and after weaning the patient from cardiopulmonary bypass. Mean arterial blood pressure in the thoracic trunk in these various positions was 62.7±3.7. left internal thora cic artery can provide sufficient blood flow to the cardiac muscles for both rest and exercise conditions.

  11. Total lymphoid irradiation in multiple sclerosis: blood lymphocytes and clinical course

    International Nuclear Information System (INIS)

    Cook, S.D.; Devereux, C.; Troiano, R.; Zito, G.; Hafstein, M.; Lavenhar, M.; Hernandez, E.; Dowling, P.C.

    1987-01-01

    We have found a significant relationship between blood lymphocyte count and prognosis in 45 patients receiving either total lymphoid irradiation or sham irradiation for chronic progressive multiple sclerosis. Patients with sustained lymphocyte counts less than 900 mm-3 for prolonged periods after treatment showed less rapid progression over the ensuing 3 years than did patients with multiple sclerosis who had lymphocyte counts above this level (p less than 0.01). Our results suggest that a simple laboratory test, the absolute blood lymphocyte count, may serve as a valuable barometer for monitoring the amount of immunosuppressive therapy needed to prevent progression in patients with multiple sclerosis, and possibly other autoimmune diseases

  12. Relationships among Ocular Blood Flow Shown by Laser Speckle Flowgraphy, Retinal Arteriosclerotic Change, and Chorioretinal Circulation Time Obtained by Fluorescein Angiography

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    Hironori Osamura

    2017-01-01

    Full Text Available Purpose. To determine the correlations among the mean blur rate (MBR in the optic nerve head (ONH shown by laser speckle flowgraphy (LSFG, retinal arteriosclerosis, and the circulation time obtained by fluorescein angiography (FA. Method. We evaluated 118 patients and assessed their time of choroidal flush, arm-to-retina time, and early and late phases of retinal circulation time (RT: sec obtained by FA. The severity of retinal arteriosclerosis was classified according to the Scheie classification. The MBR values throughout the ONH (MBR-A, in the tissue (MBR-T, and in the vessels (MBR-V were analyzed. Results. Patients with retinal vein occlusion (RVO showed prolonged early and late phases of RT compared to other ocular diseases. Single and multiple regression analyses showed that the MBR-V and Scheie classification were significantly associated with both the choroidal flush and arm-to-retina times. The incidences of RVO and MVR-V were significantly associated with the early phase of RT, and the incidences of RVO, MBR-V, Scheie classification, and gender were revealed to be factors independently contributing to the late phase of RT. Conclusion. MBR-V in the ONH and retinal arteriosclerosis are important contributing factors for the circulation time of each stage obtained by FA.

  13. Retinal Detachment

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    Adnan Riaz, MD

    2018-04-01

    Full Text Available History of present illness: A 58-year-old female presented to the emergency department reporting six days of progressive, atraumatic left eye vision loss. Her symptoms started with the appearance of dark spots and “spider webs,” and then progressed to darkening of vision in her left eye. She reports mild pain since yesterday. Her review of symptoms was otherwise negative. Ocular physical examination revealed normal external appearance, intact extraocular movements, and visual acuities of 20/25 OD and light/dark sensitivity OS. Fluorescein uptake was negative and slit lamp exam was unremarkable. Significant findings: Bedside ocular ultrasound revealed a serpentine, hyperechoic membrane that appeared tethered to the optic disc posteriorly with hyperechoic material underneath. These findings are consistent with retinal detachment (RD and associated retinal hemorrhage. Discussion: The retina is a layer of organized neurons that line the posterior portion of the posterior chamber of the eye. RD occurs when this layer separates from the underlying epithelium, resulting in ischemia and progressive photoreceptor degeneration, with potentially rapid and permanent vision loss if left untreated.1 Risk factors include advanced age, male sex (60%, race (Asians and Jews, and myopia and lattice degeneration.2 Bedside ultrasound (US performed by emergency physicians provides a valuable tool that has been used by ophthalmologists for decades to evaluate intraocular disease.1,3 Findings on bedside ultrasound consistent with RD include a hyperechoic membrane floating in the posterior chamber. RD usuallyremain tethered to the optic disc posteriorly and do not cross midline, a feature distinguishing them from posterior vitreous detachments. Associated retinal hemorrhage, seen as hyperechoic material under the retinal flap, can often be seen.1,2 US can also distinguish between “mac-on” and “mac-off” detachments. If the retina is still attached to the

  14. Peripapillary retinal thermal coagulation following electrical injury

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    Manjari Tandon

    2013-01-01

    Full Text Available In this study, we have presented the case report of a 20 year old boy who suffered an electric injury shock, following which he showed peripapillary retinal opacification and increased retinal thickening that subsequently progressed to retinal atrophy. The fluorescein angiogram revealed normal retinal circulation, thus indicating thermal damage to retina without any compromise to retinal circulation.

  15. Automatic detection and classification of malarial retinopathy- associated retinal whitening in digital retinal images

    International Nuclear Information System (INIS)

    Akram, M.U.; Alvi, A.B.N.; Khan, S.A.

    2017-01-01

    Malarial retinopathy addresses diseases that are characterized by abnormalities in retinal fundus imaging. Macular whitening is one of the distinct signs of cerebral malaria but has hardly been explored as a critical bio-marker. The paper proposes a computerized detection and classification method for malarial retinopathy using retinal whitening as a bio-marker. The paper combines various statistical and color based features to form a sound feature set for accurate detection of retinal whitening. All features are extracted at image level and feature selection is performed to detect most discriminate features. A new method for macula location is also presented. The detected macula location is further used for grading of whitening as macular or peripheral whitening. Support vector machine along with radial basis function is used for classification of normal and malarial retinopathy patients. The evaluation is performed using a locally gathered dataset from malarial patients and it achieves an accuracy of 95% for detection of retinal whitening and 100% accuracy for grading of retinal whitening as macular or non-macular. One of the major contributions of proposed method is grading of retinal whitening into macular or peripheral whitening. (author)

  16. Evolution of Outer Retinal Folds Occurring after Vitrectomy for Retinal Detachment Repair

    NARCIS (Netherlands)

    Dell'Omo, Roberto; Tan, H. Stevie; Schlingemann, Reinier O.; Bijl, Heico M.; Lesnik Oberstein, Sarit Y.; Barca, Francesco; Mura, Marco

    2012-01-01

    PURPOSE. To assess the evolution of outer retinal folds (ORFs) occurring after repair of rhegmatogenous retinal detachment (RRD) using spectral domain-optical coherence tomography (sd-OCT) and fundus autofluorescence (FAF), and to discuss their pathogenesis. METHODS. Twenty patients were operated on

  17. Retinitis pigmentosa, Coats disease and uveitis.

    Science.gov (United States)

    Solomon, A; Banin, E; Anteby, I; Benezra, D

    1999-01-01

    To study the anamnestic immune response to retinal specific antigens of two patients suffering from a rare triad of retinitis pigmentosa, Coats disease and uveitis. 17-year-old girl presented with an acute episode of panuveitis, and her 19-year-old brother suffered from chronic uveitis. On examination, both patients showed retinal vascular changes and subretinal exudations typical of Coats disease, with bone-spicule pigmentary changes as observed in retinitis pigmentosa. All routine examinations were unrevealing. However, the peripheral lymphocytes from these two siblings gave a specific anamnestic response to retinal antigens in vitro. A stimulation index of 4.6 was obtained when the sister's lymphocytes were stimulated with interphotoreceptor binding protein, IRBP--during the acute stage of the uveitis. The brother's lymphocytes showed a stimulation index of 2.7 towards S-Ag during the chronic phase of his uveitic condition. These results indicate that autoimmunity towards retinal antigens may play some role in specific types of retinitis pigmentosa. Whether these autoimmune reactions are a primary pathological mechanism or are secondary to the extensive destruction of the photoreceptor layer resulting from the retinitis pigmentosa remains debatable.

  18. Effects of sciatic-conditioned medium on neonatal rat retinal cells in vitro

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    Torres P.M.M.

    1998-01-01

    Full Text Available Schwann cells produce and release trophic factors that induce the regeneration and survival of neurons following lesions in the peripheral nerves. In the present study we examined the in vitro ability of developing rat retinal cells to respond to factors released from fragments of sciatic nerve. Treatment of neonatal rat retinal cells with sciatic-conditioned medium (SCM for 48 h induced an increase of 92.5 ± 8.8% (N = 7 for each group in the amount of total protein. SCM increased cell adhesion, neuronal survival and glial cell proliferation as evaluated by morphological criteria. This effect was completely blocked by 2.5 µM chelerythrine chloride, an inhibitor of protein kinase C (PKC. These data indicate that PKC activation is involved in the effect of SCM on retinal cells and demonstrate that fragments of sciatic nerve release trophic factors having a remarkable effect on neonatal rat retinal cells in culture.

  19. The Ins2Akita mouse as a model of early retinal complications in diabetes.

    Science.gov (United States)

    Barber, Alistair J; Antonetti, David A; Kern, Timothy S; Reiter, Chad E N; Soans, Rohit S; Krady, J Kyle; Levison, Steven W; Gardner, Thomas W; Bronson, Sarah K

    2005-06-01

    This study tested the Ins2(Akita) mouse as an animal model of retinal complications in diabetes. The Ins2(Akita) mutation results in a single amino acid substitution in the insulin 2 gene that causes misfolding of the insulin protein. The mutation arose and is maintained on the C57BL/6J background. Male mice heterozygous for this mutation have progressive loss of beta-cell function, decreased pancreatic beta-cell density, and significant hyperglycemia, as early as 4 weeks of age. Heterozygous Ins2(Akita) mice were bred to C57BL/6J mice, and male offspring were monitored for hyperglycemia, beginning at 4.5 weeks of age. After 4 to 36 weeks of hyperglycemia, the retinas were analyzed for vascular permeability, vascular lesions, leukostasis, morphologic changes of micro- and macroglia, apoptosis, retinal degeneration, and insulin receptor kinase activity. The mean blood glucose of Ins2(Akita) mice was significantly elevated, whereas the body weight at death was reduced compared with that of control animals. Compared with sibling control mice, the Ins2(Akita) mice had increased retinal vascular permeability after 12 weeks of hyperglycemia (P microglia, but no changes in expression of Muller cell glial fibrillary acidic protein. Increased apoptosis was identified by immunoreactivity for active caspase-3 after 4 weeks of hyperglycemia (P cell bodies in the retinal ganglion cell layer (P retinal complications of diabetes.

  20. Retinal Biocompatibility of Brilliant Blue G with Deuterated Water for Chromovitrectomy

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    Emmerson Badaró

    2014-01-01

    Full Text Available Purpose: To investigate the retinal biocompatibility of Brilliant Blue G with deuterated water (BBG-D2O as a vital dye for chromovitrectomy. Methods: In this animal study, 0.05 mL of 0.25 g/L Brilliant Blue G (BBG associated with 0.13 mL/mL of deuterium oxide (D2O was injected intravitreally in the right eye and the same amount of balanced salt solution (BSS was injected similarly in the left eye of rabbits. Clinical examination and histology with light microscopy were performed after seven days. Retinal cell layers were evaluated for morphologic alterations. Electroretinographic (ERG changes were also assessed at baseline and 7 days after the injections. Results: A total of 6 rabbits were included in the study. The gross histopathologic appearance of the retina, choroid, sclera and optic nerve was within normal limits without any sign of severe retinal necrosis or cystic degeneration. Light microscopy showed that BBG-D2O caused no substantial alterations in retinal layers as compared to control eyes. The injection of BBG-D2O did not induce considerable functional ERG alterations. Conclusion: Intravitreal injection of BBG-D2O 0.25 g/L seems to induce no retinal toxicity as documented by lack of functional and histological changes.

  1. Novel Localization of Peripherin 2, the Photoreceptor-Specific Retinal Degeneration Slow Protein, in Retinal Pigment Epithelium

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    Patrizia B. Uhl

    2015-01-01

    Full Text Available Retinal pigment epithelium (RPE builds the outer blood-retinal barrier of the eye. Since one typical feature of the autoimmune disease, equine recurrent uveitis (ERU, is the breakdown of this barrier, we recently performed comparative analysis of healthy and uveitic RPE. We identified for the first time peripherin 2, which is responsible for visual perception and retina development, to be localized in RPE. The purpose of this study was therefore to validate our findings by characterizing the expression patterns of peripherin 2 in RPE and retina. We also investigated whether peripherin 2 expression changes in ERU and if it is expressed by the RPE itself. Via immunohistochemistry, significant downregulation of peripherin 2 in uveitic RPE compared to the control was detectable, but there was no difference in healthy and uveitic retina. A further interesting finding was the clear distinction between peripherin 2 and the phagocytosis marker, rhodopsin, in healthy RPE. In conclusion, changes in the expression pattern of peripherin 2 selectively affect RPE, but not retina, in ERU. Moreover, peripherin 2 is clearly detectable in healthy RPE due to both phagocytosis and the expression by the RPE cells themselves. Our novel findings are very promising for better understanding the molecular mechanisms taking place on RPE in uveitis.

  2. The effect of intravitreal bevacizumab on ocular blood flow in diabetic retinopathy and branch retinal vein occlusion as measured by laser speckle flowgraphy

    Directory of Open Access Journals (Sweden)

    Nitta F

    2014-06-01

    Full Text Available Fumihiko Nitta,1 Hiroshi Kunikata,1,2 Naoko Aizawa,1 Kazuko Omodaka,1 Yukihiro Shiga,1 Masayuki Yasuda,1 Toru Nakazawa1–31Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan; 2Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, Japan; 3Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, JapanBackground: This study evaluated the effect of intravitreal injection of bevacizumab (IVB on macular edema associated with diabetic retinopathy (DME or branch retinal vein occlusion (BRVOME using laser speckle flowgraphy.Methods: A comparative interventional study of 25 eyes from 22 patients with macular edema (DME group: 12 eyes; BRVOME group: 13 eyes who underwent IVB. Mean blur rate (MBR was measured in the retinal artery, retinal vein, optic nerve head (ONH, and choroid before and after IVB. Results: In the BRVOME group, there was no significant change in MBR in the retinal artery, retinal vein or ONH, but choroidal MBR decreased significantly (P=0.04. In the DME group, the MBR in the retinal artery, retinal vein, ONH, and choroid decreased significantly (P=0.02, P=0.04, P<0.001, and P=0.04, respectively. In the DME group, pre-IVB MBR in the ONH was significantly correlated with post-IVB foveal thickness (R= -0.71, P=0.002. There was no such correlation in the BRVOME group in the ONH.Conclusion: IVB had a suppressive effect on circulation in eyes with DME but not in those with BRVOME. This suggests that this noninvasive and objective biomarker may be a useful part of pre-IVB evaluations and decision-making in DME.Keywords: macular edema, mean blur rate, optic nerve head, biomarker, ocular circulation

  3. Contacting co-culture of human retinal microvascular endothelial cells alters barrier function of human embryonic stem cell derived retinal pigment epithelial cells.

    Science.gov (United States)

    Skottman, H; Muranen, J; Lähdekorpi, H; Pajula, E; Mäkelä, K; Koivusalo, L; Koistinen, A; Uusitalo, H; Kaarniranta, K; Juuti-Uusitalo, K

    2017-10-01

    Here we evaluated the effects of human retinal microvascular endothelial cells (hREC) on mature human embryonic stem cell (hESC) derived retinal pigment epithelial (RPE) cells. The hESC-RPE cells (Regea08/017, Regea08/023 or Regea11/013) and hREC (ACBRI 181) were co-cultured on opposite sides of transparent membranes for up to six weeks. Thereafter barrier function, small molecule permeability, localization of RPE and endothelial cell marker proteins, cellular fine structure, and growth factor secretion of were evaluated. After co-culture, the RPE specific CRALBP and endothelial cell specific von Willebrand factor were appropriately localized. In addition, the general morphology, pigmentation, and fine structure of hESC-RPE cells were unaffected. Co-culture increased the barrier function of hESC-RPE cells, detected both with TEER measurements and cumulative permeability of FD4 - although the differences varied among the cell lines. Co-culturing significantly altered VEGF and PEDF secretion, but again the differences were cell line specific. The results of this study showed that co-culture with hREC affects hESC-RPE functionality. In addition, co-culture revealed drastic cell line specific differences, most notably in growth factor secretion. This model has the potential to be used as an in vitro outer blood-retinal barrier model for drug permeability testing. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Volume-dependent hemodynamic effects of blood collection in canine donors - evaluation of 13% and 15% of total blood volume depletion

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    RUI R.F. FERREIRA

    2015-03-01

    Full Text Available Background: There is no consensus regarding the blood volume that could be safely donated by dogs, ranging from 11 to 25% of its total blood volume (TBV. No previous studies evaluated sedated donors.Aim: To evaluate the hemodynamic effects of blood collection from sedated and non-sedated dogs and to understand if such effects were volume-dependent.Materials and Methods: Fifty three donations of 13% of TBV and 20 donations of 15% TBV were performed in dogs sedated with diazepam and ketamine. Additionally, a total of 30 collections of 13% TBV and 20 collections of 15% TBV were performed in non-sedated dogs. Non-invasive arterial blood pressures and pulse rates were registered before and 15 min after donation. Results: Post-donation pulse rates increased significantly in both sedated groups, with higher differences in the 15% TBV collections. Systolic arterial pressures decreased significantly in these groups, while diastolic pressures increased significantly in 13% TBV donations. Non-sedated groups revealed a slight, but significant, SBP decrease. No clinical signs related to donations were registered.Conclusion: These results suggest that the collection of 15% TBV in sedated donors induces hemodynamic variations that may compromise the harmlessness of the procedure, while it seems to be a safe procedure in non-sedated dogs.

  5. Regulation of Taurine transporter activity in cultured rat retinal ganglion cells and rat retinal Muller Cells

    International Nuclear Information System (INIS)

    Eissa, Laila A.; Smith, Sylvia B.; El-sherbeny, Amira A.

    2006-01-01

    Diabetic retinopathy is one of the most common complications of diabetes. The amino acid taurine is believed to play an antioxidant protective role in diabetic retinopathy through the scavenging of the reactive species. It is not well established whether taurine uptake is altered in retina cells during diabetic conditions. Thus, the present study was designed to investigate the changes in taurine transport in cultures of rat retinal Muller cells and rat retinal ganglion cells under conditions associated with diabetes. Taurine was abundantly taken up by retinal Muller cells and rat retinal ganglion cells under normal glycemic condition. Taurine was actively transported to rat Muller cells and rat retinal ganglion cells in a Na and Cl dependant manner. Taurine uptake further significantly elevated in both type of cells after the incubation with high glucose concentration. This effect could be attributed to the increase in osmolarity. Because Nitric Oxide (NO) is a molecule implicated in the pathogenesis of diabetes, we also determined the activity of taurine transporter in cultured rat retinal Muller cells and rat retinal ganglion cells in the presence of the NO donors, SIN-1 and SNAP. Taurine uptake was elevated above control value after 24-h incubation with low concentration of NO donors. We finally investigated the ability of neurotoxic glutamate to change taurine transporter activity in both types of cells. Uptake of taurine was significantly increased in rat retinal ganglion cells when only incubated with high concentration of glutamate. Our data provide evidence that taurine transporter is present in cultured rat retinal ganglion and Muller cells and is regulated by hyperosmolarity. The data are relevant to disease such as diabetes and neuronal degeneration where retinal cell volume may dramatically change. (author)

  6. Outcomes in bullous retinal detachment

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    Sarah P. Read

    2017-06-01

    Conclusions and importance: GRTs are an uncommon cause of retinal detachment. While pars plana vitrectomy with tamponade is standard in GRT management, there is variability in the use of scleral buckling and PFO in these cases. This is in contrast to retinal dialysis where scleral buckle alone can yield favorable results. Though a baseball ocular trauma is common, retinal involvement is rare compared to other sports injuries such as those occurring with tennis, soccer and golf. Sports trauma remains an important cause of retinal injury and patients should be counseled on the need for eye protection.

  7. Influence of transverse mode on retinal spot size and retinal injury effect: A theoretical analysis on 532-nm laser

    Directory of Open Access Journals (Sweden)

    Jia-Rui Wang

    2014-05-01

    Full Text Available The fundamental transverse mode (TEM00 is preferable for experimental and theoretical study on the laser-induced retinal injury effect, for it can produce the minimal retinal image and establish the most strict laser safety standards. But actually lasers with higher order mode were frequently used in both earlier and recent studies. Generally higher order mode leads to larger retinal spot size and so higher damage threshold, but there are few quantitative analyses on this problem. In this paper, a four-surface schematic eye model is established for human and macaque. The propagation of 532-nm laser in schematic eye is analyzed by the ABCD law of Gaussian optics. It is shown that retinal spot size increases with laser transverse mode order. For relative lower mode order, the retinal spot diameter will not exceed the minimum laser-induced retinal lesion (25 ~ 30 μm in diameter, and so has little effect on retinal damage threshold. While for higher order mode, the larger retinal spot requires more energy to induce injury and so the damage threshold increases. When beam divergence is lowered, the retinal spot size decreases correspondingly, so the effect of mode order can be compensated. The retinal spot size of macaque is slightly smaller than that of human and the ratio between them is independent of mode order. We conclude that the laser mode order has significant influence on retinal spot size but limited influence on the retinal injury effect.

  8. Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid.

    Science.gov (United States)

    Sanie-Jahromi, Fatemeh; Ahmadieh, Hamid; Soheili, Zahra-Soheila; Davari, Maliheh; Ghaderi, Shima; Kanavi, Mozhgan Rezaei; Samiei, Shahram; Deezagi, Abdolkhalegh; Pakravesh, Jalil; Bagheri, Abouzar

    2012-04-10

    Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers) during treatment of human retinal pigment epithelium (RPE) cells with amniotic fluid (AF), RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1) confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells.

  9. Applying photoacoustics to quantification of melanin concentration in retinal pigment epithelium (Conference Presentation)

    Science.gov (United States)

    Shu, Xiao; Zhang, Hao F.; Liu, Wenzhong

    2016-03-01

    The melanin in the retinal pigment epithelium (RPE) protects retina and other ocular tissues by photo-screening and acting as antioxidant and free radical scavenger. It helps maintain normal visual functions since human eye is subjected to lifelong high oxygen stress and photon exposure. Loss of the RPE melanin weakens the protection mechanism and jeopardizes ocular health. Local decrease in the RPE melanin concentration is believed to be both a cause and a sign of early-stage age-related macular degeneration (AMD), the leading blinding disease in developed world. Current technology cannot quantitatively measure the RPE melanin concentration which might be a promising marker in early AMD screening. Photoacoustic ophthalmoscopy (PAOM), as an emerging optical absorption-based imaging technology, can potentially be applied to measure the RPE melanin concentration if the dependence of the detectable photoacoustic (PA) signal amplitudes on the RPE melanin concentrations is verified. In this study, we tested the feasibility of using PA signal ratio from RPE melanin and the nearby retinal blood vessels as an indicator of the RPE melanin variation. A novel whole eye optical model was designed and Monte Carlo modeling of light (MCML) was employed. We examined the influences on quantification from PAOM axial resolution, the depth and diameter of the retinal blood vessel, and the RPE thickness. The results show that the scheme is robust to individual histological and illumination variations. This study suggests that PAOM is capable of quantitatively measuring the RPE melanin concentration in vivo.

  10. The implication of omega-3 polyunsaturated fatty acids in retinal physiology

    Directory of Open Access Journals (Sweden)

    Acar Niyazi

    2007-05-01

    Full Text Available Neuronal tissues such as the retina and the brain are characterized by their high content in phospholipids. In the retina, phospholipids can account for until 80% of total lipids and are mainly composed by species belonging to phosphatidyl-choline and phosphatidyl-ethanolamine sub-classes. Within fatty acids esterified on retinal phospholipids, omega-3 PUFAs are major components since docosahexaenoic acid (DHA can represent until 50% of total fatty acids in the photoreceptor outer segments. For long time, DHA is known to play a major role in membrane function and subsequently in visual processes by affecting permeability, fluidity, thickness and the activation of membrane-bound proteins. Today, more and more studies show that PUFAs from the omega-3 series may also operate as protective factors in retinal vascular and immuno-regulatory processes, in maintaining the physiologic redox balance and in cell survival. They may operate within complex systems involving eicosanoids, angiogenic factors, inflammatory factors and matrix metalloproteinases. This new and emerging concept based on the interrelationship of omega-3 PUFAs with neural and vascular structure and function appears to be essential when considering retinal diseases of public health significance such as age-related macular degeneration.

  11. Blood loss associated with Ring uncemented total knee replacement: comparison between continuous and intermittent suction drainage.

    Science.gov (United States)

    Wittmann, F W; Ring, P A

    1984-01-01

    In a retrospective comparison of blood loss following uncemented total knee replacement, in which either continuous or intermittent suction drainage was used, measured blood loss was significantly greater with continuous drainage. However, a method of calculating actual blood loss demonstrated no significant difference. With intermittent drainage, more blood remains undetected around the knee joint; this technique should therefore be abandoned in favour of continuous suction drainage. PMID:6747978

  12. Tranexamic acid for control of blood loss in bilateral total knee replacement in a single stage

    Directory of Open Access Journals (Sweden)

    Mandeep S Dhillon

    2011-01-01

    Full Text Available Background: Tranexamic acid (TEA reduces blood loss and red cell transfusions in patients undergoing unilateral total knee arthroplasty (TKA. However, there is not much literature regarding the use of TEA in patients undergoing bilateral TKA in a single stage and the protocols for administration of TEA in such patients are ill-defined. Materials and Methods: We carried out a case control study evaluating the effect of TEA on postoperative hemoglobin (Hb, total drain output, and number of blood units transfused in 52 patients undergoing bilateral TKA in a single stage, and compared it with 56 matched controls who did not receive TEA. Two doses of TEA were administered in doses of 10 mg / kg each (slow intravenous (IV infusion, with the first dose given just before tourniquet release of the first knee and the second dose three hours after the first one. Results: A statistically significant reduction in the total drain output and requirement of allogenic blood transfusion in cases who received TEA, as compared to the controls was observed. The postoperative Hb and Hb at the time of discharge were found to be lower in the control group, and this result was found to be statistically significant. Conclusion: TEA administered in patients undergoing single stage bilateral TKA helped reduce total blood loss and decreased allogenic blood transfusion requirements. This might be particularly relevant, where facilities such as autologous reinfusion might not be available.

  13. Acute retinal ischemia caused by controlled low ocular perfusion pressure in a porcine model. Electrophysiological and histological characterisation

    DEFF Research Database (Denmark)

    Kyhn, Maria Voss; Warfvinge, Karin; Scherfig, Erik

    2009-01-01

    The purpose of this study was to establish, and characterize a porcine model of acute, controlled retinal ischemia. The controlled retinal ischemia was produced by clamping the ocular perfusion pressure (OPP) in the left eye to 5 mm Hg for 2 h. The OPP was defined as mean arterial blood pressure...... of the amplitudes obtained in the experimental, left eye, and the control, right eye. Quantitative histology was performed to measure the survival of ganglion cells, amacrine cells and horizontal cells 2-6 weeks after the ischemic insult. An OPP of 5 mm Hg for 2h induced significant reductions in the amplitudes...... the ischemic insult. This model seems to be suitable for investigations of therapeutic initiatives in diseases involving acute retinal ischemia....

  14. Onlay bone augmentation on mouse calvarial bone using a hydroxyapatite/collagen composite material with total blood or platelet-rich plasma.

    Science.gov (United States)

    Ohba, Seigo; Sumita, Yoshinori; Umebayashi, Mayumi; Yoshimura, Hitoshi; Yoshida, Hisato; Matsuda, Shinpei; Kimura, Hideki; Asahina, Izumi; Sano, Kazuo

    2016-01-01

    The aim of this study was to assess newly formed onlay bone on mouse calvarial bone using a new artificial bone material, a hydroxyapatite/collagen composite, with total blood or platelet-rich plasma. The hydroxyapatite/collagen composite material with normal saline, total blood or platelet-rich plasma was transplanted on mouse calvarial bone. The mice were sacrificed and the specimens were harvested four weeks after surgery. The newly formed bone area was measured on hematoxylin and eosin stained specimens using Image J software. The hydroxyapatite/collagen composite materials with total blood or platelet-rich plasma induced a significantly greater amount of newly formed bone than that with normal saline. Moreover, bone marrow was observed four weeks after surgery in the transplanted materials with total blood or platelet-rich plasma but not with normal saline. However, there were no significant differences in the amount of newly formed bone between materials used with total blood versus platelet-rich plasma. The hydroxyapatite/collagen composite material was valid for onlay bone augmentation and this material should be soaked in total blood or platelet-rich plasma prior to transplantation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Oxygen delivery to the fish eye: root effect as crucial factor for elevated retinal PO2.

    Science.gov (United States)

    Waser, W; Heisler, N

    2005-11-01

    successively with standardized red blood cell (RBC) suspensions in Ringer, using trout (with Root) and human (lacking any Root effect) RBC suspension. To optimize perfusate conditions for maximal Root effect, the Root effect of trout RBCs was determined in vitro via graded acidification of individual samples equilibrated with standardized gas mixtures. During perfusion with trout RBC, PO2 at the outer retinal limit was 99 mmHg (13.2 kPa), but fell by a factor of 3.3 upon perfusion with human RBC in spite of higher total oxygen content (TO2 2.8 for trout vs 3.9 mmol l-1 for human RBC). Upon reperfusion with trout RBC, PO2 was restored immediately to the original value. This regularly observed pattern indicated a highly significant difference (P=0.003) between perfusion with trout (with Root effect; high retinal PO2) and perfusion with human (no Root effect; low retinal PO2) RBC suspension, thus clearly demonstrating that the Root effect is directly involved and a crucial prerequisite for the enhancement of PO2 in the retina of the teleost eye.

  16. Retinal protein synthesis in relationship to environmental lighting

    International Nuclear Information System (INIS)

    Hollyfield, J.G.; Anderson, R.E.

    1982-01-01

    A series of in vivo and in vitro experiments using Xenopus laevis juvenile toads was conducted to probe the relationship between environmental lighting and protein synthesis in the retina. Autoradiographic and biochemical analyses indicated that measurable changes in protein synthesis did not occur during a normal diurnal cycle when animals were conditioned to 12 hr light followed by 12 hr darkness each day (LD). However, when retinas from animals maintained in continuous darkness (DD) for 3 days were incubated with 3 H-leucine, there was a 40% reduction in the specific radioactivity of total retinal proteins compared with retinas from animals maintained in continuous light (LL) for 3 days or on the LD cycle. Retinas from DD animals injected with 3 H-leucine showed a 48% reduction in protein synthesis compared with retinas of LL animals. In autoradiographs of retinas from in vivo or in vitro experiments, grain counts were 40% lower in the total retinas of the DD animals compared with retinas of LL animals. This reduction occurred throughout the entire retina and was not restricted to any specific cell type. There was also a 35% reduction in the rate of radioactive band displacement in the rod outer segments of DD animals, although the percent of 3 H-leucine incorporated into opsin relative to total retinal protein was the same for both groups. We conclude from these studies that fluctuations in the rate of protein synthesis during the normal light-dark cycle are not detectable. However, major differences in protein synthesis are evident when animals are stressed with continuous darkness for several days. This effect is not restricted to any particular retinal layer but occurs throughout the entire retina. Moreover, prolonged darkness affects protein synthesis in extraocular tissues as well

  17. Biomonitoring of Lead, Cadmium, Total Mercury, and Methylmercury Levels in Maternal Blood and in Umbilical Cord Blood at Birth in South Korea

    Science.gov (United States)

    Kim, Yu-Mi; Chung, Jin-Young; An, Hyun Sook; Park, Sung Yong; Kim, Byoung-Gwon; Bae, Jong Woon; Han, Myoungseok; Cho, Yeon Jean; Hong, Young-Seoub

    2015-01-01

    With rising concerns of heavy metal exposure in pregnancy and early childhood, this study was conducted to assess the relationship between the lead, cadmium, mercury, and methylmercury blood levels in pregnancy and neonatal period. The study population included 104 mothers and their children pairs who completed both baseline maternal blood sampling at the second trimester and umbilical cord blood sampling at birth. The geometric mean maternal blood levels of lead, cadmium, total mercury, and methylmercury at the second trimester were 1.02 ± 1.39 µg/dL, 0.61 ± 1.51 µg/L, 2.97 ± 1.45 µg/L, and 2.39 ± 1.45 µg/L, respectively, and in the newborns, these levels at birth were 0.71 ± 1.42 µg/dL, 0.01 ± 5.31 µg/L, 4.44 ± 1.49 µg/L, and 3.67 ± 1.51 µg/L, respectively. The mean ratios of lead, cadmium, total mercury, and methylmercury levels in the newborns to those in the mothers were 0.72, 0.04, 1.76, and 1.81, respectively. The levels of most heavy metals in pregnant women and infants were higher in this study than in studies from industrialized western countries. The placenta appears to protect fetuses from cadmium; however, total mercury and methylmercury were able to cross the placenta and accumulate in fetuses. PMID:26516876

  18. Giant Retinal Tear With Retinal Detachment in Regressed Aggressive Posterior Retinopathy of Prematurity Treated by Laser.

    Science.gov (United States)

    Chandra, Parijat; Tewari, Ruchir; Salunkhe, Nitesh; Kumawat, Devesh; Kumar, Vinod

    2017-06-29

    Rhegmatogenous retinal detachment after successfully regressed retinopathy of prematurity is a rare occurrence. Late onset rhegmatogenous retinal detachment has been reported infrequently. The authors report a case of aggressive posterior retinopathy of prematurity that underwent uneventful regression after laser photocoagulation and later developed an inoperable closed funnel retinal detachment due to a giant retinal tear. This case represents the earliest development of such complications in regressed aggressive posterior retinopathy of prematurity treated by laser. Development of a giant retinal tear has also not been previously reported after laser treatment. This case highlights that successful regression of severe retinopathy of prematurity does not safeguard against future complications and requires frequent long-term follow-up. [J Pediatr Ophthalmol Strabismus. 2017;54:e34-e36.]. Copyright 2017, SLACK Incorporated.

  19. Updated cannulation technique for tissue plasminogen activator injection into peripapillary retinal vein for central retinal vein occlusion.

    Science.gov (United States)

    van Overdam, Koen A; Missotten, Tom; Spielberg, Leigh H

    2015-12-01

    To update the surgical technique in which a vitrectomy is performed and a retinal branch vein is cannulated and infused with recombinant tissue plasminogen activator (RTPA) to treat central retinal vein occlusion (CRVO) in patients who present with very low visual acuity (VA). Twelve consecutive patients (12 eyes) with CRVO and low VA (logMAR >1.00) at presentation were treated using this method. Cannulation of a peripapillary retinal vein and stable injection of RTPA was successfully performed without surgery-related complications in all 12 eyes. At 12 months after surgery, 8 of the 12 patients (67%) experienced at least one line of improvement in best corrected visual acuity; 6 of the 12 (50%) improved ≥5 lines and 2 (17%) improved ≥8 lines. After additional grid laser and/or subconjunctival or intravitreal corticosteroids, the mean decrease in central foveal thickness was 260 μm, and the mean total macular volume decreased from 12.10 mm(3) to 9.24 mm(3) . Four patients received panretinal photocoagulation to treat either iris neovascularization (n = 2) or neovascularization of the retina and/or disc (n = 2). Administration of RTPA via a peripapillary vein using this updated technique provides an alternative or additional treatment option for patients with very low VA after CRVO. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  20. Thickening of inner retinal layers in the parafovea after bariatric surgery in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Brynskov, Troels; Laugesen, Caroline S; Floyd, Andrea K

    2016-01-01

    . METHODS: We examined 51 patients with T2D 2 weeks before and 1, 3, 6 and 12 months after bariatric surgery. Retinal thickness was measured with optical coherence tomography and automated segmentation in the fovea, parafovea and perifovea in each retinal layer. Retinal vessels were semiautomatically...... measured in a zone 0.5-1 disc diameters from the optic disc. RESULTS: The total macula thickened with a peak after 6 months in both univariate (2.7 ± 0.4 μm, p

  1. Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid

    Directory of Open Access Journals (Sweden)

    Sanie-Jahromi Fatemeh

    2012-04-01

    Full Text Available Abstract Background Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers during treatment of human retinal pigment epithelium (RPE cells with amniotic fluid (AF, RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Results Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1 confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Conclusion Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells.

  2. Screening for retinitis in children with probable systemic ...

    African Journals Online (AJOL)

    CMV retinitis may be prevented by timely diagnosis and treatment. This study aimed to .... retinitis are: 'a fulminant picture of retinal vasculitis and vascular sheathing with areas of yellow-white, full thickness, retinal necrosis producing retinal oedema associated ... and intravenous foscarnet as alternatives.[4] Although CMV- ...

  3. Bioelectronic retinal prosthesis

    Science.gov (United States)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  4. Retinal ganglion cells in the eastern newt Notophthalmus viridescens: topography, morphology, and diversity.

    Science.gov (United States)

    Pushchin, Igor I; Karetin, Yuriy A

    2009-10-20

    The topography and morphology of retinal ganglion cells (RGCs) in the eastern newt were studied. Cells were retrogradely labeled with tetramethylrhodamine-conjugated dextran amines or horseradish peroxidase and examined in retinal wholemounts. Their total number was 18,025 +/- 3,602 (mean +/- SEM). The spatial density of RGCs varied from 2,100 cells/mm(2) in the retinal periphery to 4,500 cells/mm(2) in the dorsotemporal retina. No prominent retinal specializations were found. The spatial resolution estimated from the spatial density of RGCs varied from 1.4 cycles per degree in the periphery to 1.95 cycles per degree in the region of the peak RGC density. A sample of 68 cells was camera lucida drawn and subjected to quantitative analysis. A total of 21 parameters related to RGC morphology and stratification in the retina were estimated. Partitionings obtained by using different clustering algorithms combined with automatic variable weighting and dimensionality reduction techniques were compared, and an effective solution was found by using silhouette analysis. A total of seven clusters were identified and associated with potential cell types. Kruskal-Wallis ANOVA-on-Ranks with post hoc Mann-Whitney U tests showed significant pairwise between-cluster differences in one or more of the clustering variables. The average silhouette values of the clusters were reasonably high, ranging from 0.52 to 0.79. Cells assigned to the same cluster displayed similar morphology and stratification in the retina. The advantages and limitations of the methodology adopted are discussed. The present classification is compared with known morphological and physiological RGC classifications in other salamanders.

  5. Tractional retinal detachment in Usher syndrome type II.

    Science.gov (United States)

    Rani, Alka; Pal, Nikhil; Azad, Raj Vardhan; Sharma, Yog Raj; Chandra, Parijat; Vikram Singh, Deependra

    2005-08-01

    Retinal detachment is a rare complication in patients with retinitis pigmentosa. A case is reported of tractional retinal detachment in a patient with retinitis pigmentosa and sensorineural hearing loss, which was diagnosed as Usher syndrome type II. Because of the poor visual prognosis, the patient refused surgery in that eye. Tractional retinal detachment should be added to the differential diagnoses of visual loss in patients with retinitis pigmentosa.

  6. Inherited Retinal Degenerative Disease Registry

    Science.gov (United States)

    2017-09-13

    Eye Diseases Hereditary; Retinal Disease; Achromatopsia; Bardet-Biedl Syndrome; Bassen-Kornzweig Syndrome; Batten Disease; Best Disease; Choroidal Dystrophy; Choroideremia; Cone Dystrophy; Cone-Rod Dystrophy; Congenital Stationary Night Blindness; Enhanced S-Cone Syndrome; Fundus Albipunctatus; Goldmann-Favre Syndrome; Gyrate Atrophy; Juvenile Macular Degeneration; Kearns-Sayre Syndrome; Leber Congenital Amaurosis; Refsum Syndrome; Retinitis Pigmentosa; Retinitis Punctata Albescens; Retinoschisis; Rod-Cone Dystrophy; Rod Dystrophy; Rod Monochromacy; Stargardt Disease; Usher Syndrome

  7. Outcomes of macular hole surgery in patients treated intraoperatively for retinal breaks and/or lattice degeneration.

    Science.gov (United States)

    Hwang, John; Escariao, Paulo; Iranmanesh, Reza; Tosi, Gian Marco; Chang, Stanley

    2007-01-01

    To assess the outcome of macular hole surgery in patients treated intraoperatively for retinal breaks and/or lattice degeneration. Retrospective review of patients who underwent macular hole surgery from September 1998 to August 2005. Outcomes in eyes that received intraoperative endolaser photocoagulation for retinal breaks and/or lattice degeneration were compared to outcomes in a case-matched control group without retinal breaks or lattice degeneration. A total of 235 consecutive macular hole surgery cases were reviewed. Twenty-four eyes from 24 patients received intraoperative endolaser photocoagulation for retinal breaks and/or lattice degeneration. Macular hole closure occurred in all case and control eyes without any incidence of postoperative retinal detachment. Best-corrected visual acuity improvement of at least three Snellen lines occurred in 100% of case eyes and 92% of control eyes. Outcomes of macular hole surgery in patients with retinal breaks and/or lattice degeneration are similar to outcomes in the overall population when these conditions are treated with intraoperative endolaser photocoagulation. Postoperative retinal detachment does not appear to be correlated with treated retinal tears and greater attention should focus on detecting and managing intraoperative breaks. In our hands, routine use panoramic viewing has replaced indirect ophthalmoscopy, by saving time, and reducing the risk of contamination.

  8. Retinal Vessels Segmentation Techniques and Algorithms: A Survey

    Directory of Open Access Journals (Sweden)

    Jasem Almotiri

    2018-01-01

    Full Text Available Retinal vessels identification and localization aim to separate the different retinal vasculature structure tissues, either wide or narrow ones, from the fundus image background and other retinal anatomical structures such as optic disc, macula, and abnormal lesions. Retinal vessels identification studies are attracting more and more attention in recent years due to non-invasive fundus imaging and the crucial information contained in vasculature structure which is helpful for the detection and diagnosis of a variety of retinal pathologies included but not limited to: Diabetic Retinopathy (DR, glaucoma, hypertension, and Age-related Macular Degeneration (AMD. With the development of almost two decades, the innovative approaches applying computer-aided techniques for segmenting retinal vessels are becoming more and more crucial and coming closer to routine clinical applications. The purpose of this paper is to provide a comprehensive overview for retinal vessels segmentation techniques. Firstly, a brief introduction to retinal fundus photography and imaging modalities of retinal images is given. Then, the preprocessing operations and the state of the art methods of retinal vessels identification are introduced. Moreover, the evaluation and validation of the results of retinal vessels segmentation are discussed. Finally, an objective assessment is presented and future developments and trends are addressed for retinal vessels identification techniques.

  9. Relationship between target organ damage and blood pressure, retinal vessel calibre, oxidative stress and polymorphisms in VAV-2 and VAV-3 genes in patients with hypertension: a case-control study protocol (LOD-Hipertension).

    Science.gov (United States)

    Gomez-Marcos, Manuel A; Gonzalez-Sarmiento, Rogelio; Recio-Rodríguez, José I; Agudo-Conde, Cristina; Gamella-Pozuelo, Luis; Perretta-Tejedor, Nuria; Martínez-Salgado, Carlos; García-Ortiz, Luis

    2014-04-03

    Target organ damage (TOD) is associated with increased cardiovascular risk. The study objectives were to analyse the relationship of TOD to blood pressure, size of retinal arteries and veins, oxidative stress and different polymorphisms in the VAV-2 and VAV-3 genes in participants with hypertension. A case-control study to analyse the relationship between clinical, biochemical and genetic parameters and presence of cardiac, vascular and renal TOD in 486 patients with hypertension. Participants with TOD will be considered as cases, and those without TOD will be enrolled as controls. This will be a collaborative study conducted by the groups of Primary Care, Cardiovascular and Metabolic and Degenerative Diseases of the Instituto de Investigación Biomédica of Salamanca (IBSAL). Assessment of cardiac, renal and vascular TOD. Measurement of peripheral and central blood pressure, size of eye fundus arteries and veins, and oxidative stress, and polymorphisms in the VAV-2 and VAV-3 genes. The study will be conducted after approval is obtained from the Ethics Committee of Hospital Clínico Universitario of Salamanca. All study participants will sign an informed consent to agree to participate in the study, and another consent to agree on the genetic study, in compliance with the Declaration of Helsinki and the WHO standards for observational studies. The results of this study will allow for an understanding of the relationship of the different TODs with blood pressure, retinal artery and vein diameters, oxidative stress and polymorphisms in VAV-2 and VAV-3 genes. Clinical Trials. gov Identifier: NCT02022618.

  10. Allogenic blood transfusion following total hip arthroplasty: results from the nationwide inpatient sample, 2000 to 2009.

    Science.gov (United States)

    Saleh, Anas; Small, Travis; Chandran Pillai, Aiswarya Lekshmi Pillai; Schiltz, Nicholas K; Klika, Alison K; Barsoum, Wael K

    2014-09-17

    The large-scale utilization of allogenic blood transfusion and its associated outcomes have been described in critically ill patients and those undergoing high-risk cardiac surgery but not in patients undergoing elective total hip arthroplasty. The objective of this study was to determine the trends in utilization and outcomes of allogenic blood transfusion in patients undergoing primary total hip arthroplasty in the United States from 2000 to 2009. An observational cohort of 2,087,423 patients who underwent primary total hip arthroplasty from 2000 to 2009 was identified in the Nationwide Inpatient Sample. International Classification of Diseases, Ninth Revision, Clinical Modification procedure codes 99.03 and 99.04 were used to identify patients who received allogenic blood products during their hospital stay. Risk factors for allogenic transfusions were identified with use of multivariable logistic regression models. We used propensity score matching to estimate the adjusted association between transfusion and surgical outcomes. The rate of allogenic blood transfusion increased from 11.8% in 2000 to 19.0% in 2009. Patient-related risk factors for receiving an allogenic blood transfusion include an older age, female sex, black race, and Medicaid insurance. Hospital-related risk factors include rural location, smaller size, and non-academic status. After adjusting for confounders, allogenic blood transfusion was associated with a longer hospital stay (0.58 ± 0.02 day; p conservation methods. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

  11. Evaluation of the contribution of smoking to total blood polonium-210 in Saudi population

    Energy Technology Data Exchange (ETDEWEB)

    Shabana, E.I. E-mail: eshabana@kacst.edu.sa; Elaziz, M.A. Abd; Al-Arifi, M.N.; Al-Dhawailie, A.A.; Al-Bokari, M.M-A

    2000-01-01

    A preliminary study of {sup 210}Po concentrations in the blood of some smokers and nonsmokers is presented in order to evaluate the contribution of smoking to total blood {sup 210}Po in Saudi population. Blood samples were collected from 30 volunteers and analyzed by high resolution {alpha}-spectrometry using a radiochemical technique. The technique is based on the separation of polonium from other components of the sample by wet ashing with an HNO{sub 3}/H{sub 2}O{sub 2} oxidizing mixture and spontaneous deposition on a silver disc under the relevant conditions for {alpha}-particle counting. The results indicated that a significant fraction (about 30%) of blood {sup 210}Po is related to smoking.

  12. Na,K-ATPase alpha isoforms at the blood-cerebrospinal fluid-trigeminal nerve and blood-retina interfaces in the rat.

    Science.gov (United States)

    Arakaki, Xianghong; McCleary, Paige; Techy, Matthew; Chiang, Jiarong; Kuo, Linus; Fonteh, Alfred N; Armstrong, Brian; Levy, Dan; Harrington, Michael G

    2013-03-14

    Cerebrospinal fluid (CSF) sodium concentration increases during migraine attacks, and both CSF and vitreous humor sodium increase in the rat migraine model. The Na,K-ATPase is a probable source of these sodium fluxes. Since Na,K-ATPase isoforms have different locations and physiological roles, our objective was to establish which alpha isoforms are present at sites where sodium homeostasis is disrupted. Specific Na,K-ATPase alpha isoforms were identified in rat tissues by immunohistochemistry at the blood-CSF barrier at the choroid plexus, at the blood-CSF-trigeminal barrier at the meninges, at the blood-retina barrier, and at the blood-aqueous barrier at the ciliary body. Calcitonin gene-related peptide (CGRP), occludin, or von Willibrand factor (vWF) were co-localized with Na,K-ATPase to identify trigeminal nociceptor fibers, tight junctions, and capillary endothelial cells respectively. The Na,K-ATPase alpha-2 isoform is located on capillaries and intensely at nociceptive trigeminal nerve fibers at the meningeal blood-CSF-trigeminal barrier. Alpha-1 and -3 are lightly expressed on the trigeminal nerve fibers but not at capillaries. Alpha-2 is expressed at the blood-retina barriers and, with alpha-1, at the ciliary body blood aqueous barrier. Intense apical membrane alpha-1 was associated with moderate cytoplasmic alpha-2 expression at the choroid plexus blood-CSF barrier. Na,K-ATPase alpha isoforms are present at the meningeal, choroid plexus, and retinal barriers. Alpha-2 predominates at the capillary endothelial cells in the meninges and retinal ganglion cell layer.

  13. Dendrobium chrysotoxum Lindl. Alleviates Diabetic Retinopathy by Preventing Retinal Inflammation and Tight Junction Protein Decrease

    Science.gov (United States)

    Yu, Zengyang; Gong, Chenyuan; Lu, Bin; Yang, Li; Sheng, Yuchen; Ji, Lili; Wang, Zhengtao

    2015-01-01

    Diabetic retinopathy (DR) is a serious complication of diabetes mellitus. This study aimed to observe the alleviation of the ethanol extract of Dendrobium chrysotoxum Lindl. (DC), a traditional Chinese herbal medicine, on DR and its engaged mechanism. After DC (30 or 300 mg/kg) was orally administrated, the breakdown of blood retinal barrier (BRB) in streptozotocin- (STZ-) induced diabetic rats was attenuated by DC. Decreased retinal mRNA expression of tight junction proteins (including occludin and claudin-1) in diabetic rats was also reversed by DC. Western blot analysis and retinal immunofluorescence staining results further confirmed that DC reversed the decreased expression of occludin and claudin-1 proteins in diabetic rats. DC reduced the increased retinal mRNA expressions of intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor α (TNFα), interleukin- (IL-) 6, and IL-1β in diabetic rats. In addition, DC alleviated the increased 1 and phosphorylated p65, IκB, and IκB kinase (IKK) in diabetic rats. DC also reduced the increased serum levels of TNFα, interferon-γ (IFN-γ), IL-6, IL-1β, IL-8, IL-12, IL-2, IL-3, and IL-10 in diabetic rats. Therefore, DC can alleviate DR by inhibiting retinal inflammation and preventing the decrease of tight junction proteins, such as occludin and claudin-1. PMID:25685822

  14. Central retinal artery occlusion in a patient with ANCA-negative Churg-Strauss syndrome

    Science.gov (United States)

    Kumano, Yuji; Yoshida, Noriko; Fukuyama, Satoru; Miyazaki, Masanori; Enaida, Hiroshi; Matsui, Takaaki

    2012-01-01

    Ocular involvement in Churg-Strauss syndrome is infrequent. We describe the case of a 54-year-old woman with eosinophilia and involvement of the respiratory tract, skin, and peripheral nervous system, fulfilling the American College of Rheumatology criteria for Churg-Strauss syndrome. The patient presented with acute, painless vision loss in her right eye. Central retinal artery occlusion (CRAO) without accompanying retinal vasculitis was diagnosed by angiographic findings and funduscopic findings of retinal whitening with a cherry-red spot. Although her antineutrophil cytoplasmic antibody (ANCA) status was negative, CRAO was thought to be an ocular manifestation of Churg-Strauss syndrome, and appropriate treatment was planned. She was treated with high-dose corticosteroids and anticoagulant therapy. Her macular edema improved, but visual recovery was poor. Specific therapy to alter inflammation, blood coagulation, and rheology reportedly plays an important role in ANCA-positive patients with Churg-Strauss syndrome who develop CRAO. Regardless of ANCA status, high-dose corticosteroids should be considered for CRAO in patients with Churg-Strauss syndrome, as discussed in this case. PMID:22927731

  15. Concentric retinitis pigmentosa: clinicopathologic correlations.

    Science.gov (United States)

    Milam, A H; De Castro, E B; Smith, J E; Tang, W X; John, S K; Gorin, M B; Stone, E M; Aguirre, G D; Jacobson, S G

    2001-10-01

    Progressive concentric (centripetal) loss of vision is one pattern of visual field loss in retinitis pigmentosa. This study provides the first clinicopathologic correlations for this form of retinitis pigmentosa. A family with autosomal dominant concentric retinitis pigmentosa was examined clinically and with visual function tests. A post-mortem eye of an affected 94 year old family member was processed for histopathology and immunocytochemistry with retinal cell specific antibodies. Unrelated simplex/multiplex patients with concentric retinitis pigmentosa were also examined. Affected family members of the eye donor and patients from the other families had prominent peripheral pigmentary retinopathy with more normal appearing central retina, good visual acuity, concentric field loss, normal or near normal rod and cone sensitivity within the preserved visual field, and reduced rod and cone electroretinograms. The eye donor, at age 90, had good acuity and function in a central island. Grossly, the central region of the donor retina appeared thinned but otherwise normal, while the far periphery contained heavy bone spicule pigment. Microscopically the central retina showed photoreceptor outer segment shortening and some photoreceptor cell loss. The mid periphery had a sharp line of demarcation where more central photoreceptors were near normal except for very short outer segments and peripheral photoreceptors were absent. Rods and cones showed abrupt loss of outer segments and cell death at this interface. It is concluded that concentric retinitis pigmentosa is a rare but recognizable phenotype with slowly progressive photoreceptor death from the far periphery toward the central retina. The disease is retina-wide but shows regional variation in severity of degeneration; photoreceptor death is severe in the peripheral retina with an abrupt edge between viable and degenerate photoreceptors. Peripheral to central gradients of unknown retinal molecule(s) may be defective

  16. Lattice degeneration of the retina and retinal detachment.

    Science.gov (United States)

    Semes, L P

    1992-01-01

    Lattice retinal degeneration is considered the most significant peripheral retinal disorder potentially predisposing to retinal breaks and retinal detachment. Lattice degeneration affects the vitreous and inner retinal layers with secondary changes as deep as the retinal pigment epithelium and perhaps the choriocapillaris. Variations in clinical appearance are the rule; geographically, lattice lesions favor the vertical meridians between the equator and the ora serrata. Lattice degeneration begins early in life and has been reported in sequential generations of the same family. Along with its customary bilateral occurrence, lattice shares other characteristics of a dystrophy. The association between the vitreous and retina in lattice lesions may be responsible for the majority of lattice-induced retinal detachments. The tumultuous event of posterior vitreous separation in the presence of abnormally strong vitreoretinal adherence is the trigger for a retinal tear that, in turn, may lead to retinal detachment. Although retinal holes in young patients with lattice degeneration may play a role in the evolution of retinal detachment, the clinical course of lattice degeneration seems to be one of dormancy rather than of progressive change. This discussion outlines the pathophysiology of lattice retinal degeneration and the relationship of pathophysiology to clinical presentation. The epidemiology of lattice degeneration is summarized, as are the possible precursors to retinal detachment. A clinical characterization of the natural history of lattice degeneration is offered, and interventions for complications are described. To conclude, management strategies from a primary-care standpoint are reviewed.

  17. Bilateral acute retinal necrosis-A case report

    Directory of Open Access Journals (Sweden)

    Prasad Palimar

    1992-01-01

    Full Text Available A 42 year old man presented with acute bilateral uveitis and necrotizing retinitis. Systemic investigations including test for AIDS and CMV retinitis were negative. Despite oral Acyclovir, both eyes progressed rapidly to retinal detachment with loss of vision. Early recognition is necessary to diagnose the bilateral acute retinal necrosis syndrome and initiate treatment. Bilateral acute retinal necrosis (BARN is a term first coined by Young and Bird in 1978 although the syndrome had been originally described by Urayama et al as an unilateral condition. This syndrome is characterized by the triad of acute confluent peripheral necrotizing retinitis, moderate to severe vasculitis and vitritis in an otherwise healthy individual. Rhegmatogenous retinal detachment occurs within two to three months of the onset of the disease and the second eye is involved in 36% of patients, usually within 6 weeks. We herein report a patient who presented with simultaneous BARN leading to retinal detachment in a matter of days. Also, to our knowledge this is the first report of this condition in India.

  18. Non-syndromic retinitis pigmentosa

    NARCIS (Netherlands)

    Verbakel, S.K. (Sanne K.); R.A.C. van Huet (Ramon A. C.); C.J.F. Boon (Camiel); A.I. Hollander (Anneke); R.W.J. Collin (Rob); C.C.W. Klaver (Caroline); C. Hoyng (Carel); R. Roepman (Ronald); B.J. Klevering (Jeroen)

    2018-01-01

    textabstractRetinitis pigmentosa (RP) encompasses a group of inherited retinal dystrophies characterized by the primary degeneration of rod and cone photoreceptors. RP is a leading cause of visual disability, with a worldwide prevalence of 1:4000. Although the majority of RP cases are non-syndromic,

  19. Retinal Image Preprocessing: Background and Noise Segmentation

    Directory of Open Access Journals (Sweden)

    Usman Akram

    2012-09-01

    Full Text Available Retinal images are used for the automated screening and diagnosis of diabetic retinopathy. The retinal image quality must be improved for the detection of features and abnormalities and for this purpose preprocessing of retinal images is vital. In this paper, we present a novel automated approach for preprocessing of colored retinal images. The proposed technique improves the quality of input retinal image by separating the background and noisy area from the overall image. It contains coarse segmentation and fine segmentation. Standard retinal images databases Diaretdb0, Diaretdb1, DRIVE and STARE are used to test the validation of our preprocessing technique. The experimental results show the validity of proposed preprocessing technique.

  20. Automatic Vessel Segmentation on Retinal Images

    Institute of Scientific and Technical Information of China (English)

    Chun-Yuan Yu; Chia-Jen Chang; Yen-Ju Yao; Shyr-Shen Yu

    2014-01-01

    Several features of retinal vessels can be used to monitor the progression of diseases. Changes in vascular structures, for example, vessel caliber, branching angle, and tortuosity, are portents of many diseases such as diabetic retinopathy and arterial hyper-tension. This paper proposes an automatic retinal vessel segmentation method based on morphological closing and multi-scale line detection. First, an illumination correction is performed on the green band retinal image. Next, the morphological closing and subtraction processing are applied to obtain the crude retinal vessel image. Then, the multi-scale line detection is used to fine the vessel image. Finally, the binary vasculature is extracted by the Otsu algorithm. In this paper, for improving the drawbacks of multi-scale line detection, only the line detectors at 4 scales are used. The experimental results show that the accuracy is 0.939 for DRIVE (digital retinal images for vessel extraction) retinal database, which is much better than other methods.

  1. [Preventive treatment of retinal detachment in aphakic eyes].

    Science.gov (United States)

    Regnault, F; Bregeat, P

    1977-01-01

    We have examined 243 cases with retinal detachment occurring within 6 months following cataract surgery. In 92 of them retinal tear was due to lattice degeneration, in 66 to snail track degeneration and in 17 to equatorial degeneration. 290 other patients had preventive treatments. In this group, there were only 10 cases of retinal detachment. 9 out of 22 patients who had no preventive treatment suffered retinal detachments. There are two reasons for the occurrence of this retinal detachment in the 6 months following cataract surgery in eyes where retinal degenerations are found: (1) surgical trauma even with cryoextraction is responsible for traction of the vitreous base, (2) rapid disappearance of the hyaluronic acid in the aphakic vitreous is responsible for the degradation of the vitreous with formation of large zones of liquid vitreous. When adhesion between the vitreous and the retinal degeneration area remains, the traction is responsible for retinal tear or retinal detachment. The importance of the preventive treatment of retinal lesions prior to cataract surgery should be stressed.

  2. Risk of progression in macula-on rhegmatogenous retinal detachment.

    Science.gov (United States)

    Callizo, Josep; Pfeiffer, Sebastian; Lahme, Eva; van Oterendorp, Christian; Khattab, Mohammed; Bemme, Sebastian; Kulanga, Miroslav; Hoerauf, Hans; Feltgen, Nicolas

    2017-08-01

    To identify factors that may lead to a rapid progression in macula-on rhegmatogenous retinal detachment (RRD), in particular, those that may lead to macular involvement. Observational, prospective, single-center study. Patients referred for surgery due to primary rhegmatogenous retinal detachment with the macula on between 2009 and 2013 were included. Relevant factors analyzed included age, time delay until surgery, lens status, myopia, the detachment's location and configuration as well as number, size and type of retinal breaks. Eyes underwent optical coherence tomography to detect macular detachment. A multivariate analysis was performed to investigate the effect of several factors in the progression of retinal detachment. A total of 116 eyes of 116 patients were included. Mean time delay between admission and surgery was 1.8 ± 1.4 days. Progression was observed in 19.8% of the eyes. Of those, 47.8% presented macular detachment. Ten of the 11 (90.9%) eyes presenting progression involving the macula also exhibited a bullous configuration, which was the only parameter that correlated significantly with detachment progression in patients with (p = 0.0036) and without (p = 0.0014) macular involvement. For the first time in a prospective trial, a bullous configuration was found to be a highly significant predictor for progression in macula-on detachments. Our data support prompt surgery in patients diagnosed with bullous macula-on RRD.

  3. Inner Retinal Oxygen Extraction Fraction in Response to Light Flicker Stimulation in Humans

    Science.gov (United States)

    Felder, Anthony E.; Wanek, Justin; Blair, Norman P.; Shahidi, Mahnaz

    2015-01-01

    Purpose Light flicker has been shown to stimulate retinal neural activity, increase blood flow, and alter inner retinal oxygen metabolism (MO2) and delivery (DO2). The purpose of the study was to determine the change in MO2 relative to DO2 due to light flicker stimulation in humans, as assessed by the inner retinal oxygen extraction fraction (OEF). Methods An optical imaging system, based on a modified slit lamp biomicroscope, was developed for simultaneous measurements of retinal vascular diameter (D) and oxygen saturation (SO2). Retinal images were acquired in 20 healthy subjects before and during light flicker stimulation. Arterial and venous D (DA and DV) and SO2 (SO2A and SO2V) were quantified within a circumpapillary region. Oxygen extraction fraction was defined as the ratio of MO2 to DO2 and was calculated as (SO2A − SO2V)/SO2A. Reproducibility of measurements was assessed. Results Coefficients of variation and intraclass correlation coefficients of repeated measurements were <5% and ≥0.83, respectively. During light flicker stimulation, DA, DV , and SO2V significantly increased (P ≤ 0.004). Oxygen extraction fraction was 0.37 ± 0.08 before light flicker and significantly decreased to 0.31 ± 0.07 during light flicker (P = 0.001). Conclusions Oxygen extraction fraction before and during light flicker stimulation is reported in human subjects for the first time. Oxygen extraction fraction decreased during light flicker stimulation, indicating the change in DO2 exceeded that of MO2. This technology is potentially useful for the detection of changes in OEF response to light flicker in physiological and pathological retinal conditions. PMID:26469748

  4. Analysis of retinal function using chromatic pupillography in retinitis pigmentosa and the relationship to electrically evoked phosphene thresholds.

    Science.gov (United States)

    Kelbsch, Carina; Maeda, Fumiatsu; Lisowska, Jolanta; Lisowski, Lukasz; Strasser, Torsten; Stingl, Krunoslav; Wilhelm, Barbara; Wilhelm, Helmut; Peters, Tobias

    2017-06-01

    To analyse pupil responses to specific chromatic stimuli in patients with advanced retinitis pigmentosa (RP) to ascertain whether chromatic pupillography can be used as an objective marker for residual retinal function. To examine correlations between parameters of the pupil response and the perception threshold of electrically evoked phosphenes. Chromatic pupillography was performed in 40 patients with advanced RP (visual acuity Chromatic pupillography demonstrated a significant decrease in outer retinal photoreceptor responses but a persisting and disinhibited intrinsic photosensitive retinal ganglion cell function in advanced RP. These phenomena may be useful as an objective marker for the efficacy of any interventional treatment for hereditary retinal diseases as well as for the selection of suitable patients for an electronic retinal implant. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  5. Retinal detachment in black South Africans

    African Journals Online (AJOL)

    low incidence of retinal detachment in black patients is not known. ... a retinal break. Predisposing factors include peripheral retinal degenerations, myopia, aphakia and trauma. Delay in presentation increases the difficulty in achieving adequate surgical ... On examination, note was taken of the visual acuity in both eyes, the ...

  6. Enface Thickness Mapping and Reflectance Imaging of Retinal Layers in Diabetic Retinopathy.

    Science.gov (United States)

    Francis, Andrew W; Wanek, Justin; Lim, Jennifer I; Shahidi, Mahnaz

    2015-01-01

    To present a method for image segmentation and generation of enface thickness maps and reflectance images of retinal layers in healthy and diabetic retinopathy (DR) subjects. High density spectral domain optical coherence tomography (SDOCT) images were acquired in 10 healthy and 4 DR subjects. Customized image analysis software identified 5 retinal cell layer interfaces and generated thickness maps and reflectance images of the total retina (TR), inner retina (IR), outer retina (OR), and the inner segment ellipsoid (ISe) band. Thickness maps in DR subjects were compared to those of healthy subjects by generating deviation maps which displayed retinal locations with thickness below, within, and above the normal 95% confidence interval. In healthy subjects, TR and IR thickness maps displayed the foveal depression and increased thickness in the parafoveal region. OR and ISe thickness maps showed increased thickness at the fovea, consistent with normal retinal anatomy. In DR subjects, thickening and thinning in localized regions were demonstrated on TR, IR, OR, and ISe thickness maps, corresponding to retinal edema and atrophy, respectively. TR and OR reflectance images showed reduced reflectivity in regions of increased thickness. Hard exudates appeared as hyper-reflective spots in IR reflectance images and casted shadows on the deeper OR and ISe reflectance images. The ISe reflectance image clearly showed the presence of focal laser scars. Enface thickness mapping and reflectance imaging of retinal layers is a potentially useful method for quantifying the spatial and axial extent of pathologies due to DR.

  7. Automated detection and classification of major retinal vessels for determination of diameter ratio of arteries and veins

    Science.gov (United States)

    Muramatsu, Chisako; Hatanaka, Yuji; Iwase, Tatsuhiko; Hara, Takeshi; Fujita, Hiroshi

    2010-03-01

    Abnormalities of retinal vasculatures can indicate health conditions in the body, such as the high blood pressure and diabetes. Providing automatically determined width ratio of arteries and veins (A/V ratio) on retinal fundus images may help physicians in the diagnosis of hypertensive retinopathy, which may cause blindness. The purpose of this study was to detect major retinal vessels and classify them into arteries and veins for the determination of A/V ratio. Images used in this study were obtained from DRIVE database, which consists of 20 cases each for training and testing vessel detection algorithms. Starting with the reference standard of vasculature segmentation provided in the database, major arteries and veins each in the upper and lower temporal regions were manually selected for establishing the gold standard. We applied the black top-hat transformation and double-ring filter to detect retinal blood vessels. From the extracted vessels, large vessels extending from the optic disc to temporal regions were selected as target vessels for calculation of A/V ratio. Image features were extracted from the vessel segments from quarter-disc to one disc diameter from the edge of optic discs. The target segments in the training cases were classified into arteries and veins by using the linear discriminant analysis, and the selected parameters were applied to those in the test cases. Out of 40 pairs, 30 pairs (75%) of arteries and veins in the 20 test cases were correctly classified. The result can be used for the automated calculation of A/V ratio.

  8. Effects of exercise and respiration on blood flow in total cavopulmonary connection

    DEFF Research Database (Denmark)

    Hjortdal, V E; Emmertsen, K; Stenbøg, E

    2003-01-01

    BACKGROUND: Little is known about blood flow and its relationship to respiration during exercise in patients with total cavopulmonary connection (TCPC). METHODS AND RESULTS: We studied 11 patients 12.4+/-4.6 years (mean+/-SD) of age 5.9+/-2.8 years (mean+/-SD) after TCPC operation. Real-time MRI...

  9. Safety of retransfusing shed blood after local infiltration analgesia in total knee arthroplasty

    NARCIS (Netherlands)

    Thomassen, B.J.; Pool, L.; Van Der Flier, R.; Stienstra, R.; in 't Veld, B.A.

    2012-01-01

    We investigated the safety of LIA (local infiltration analgesia) combined with retransfusion of drained blood. Total knee arthroplasty patients received two peri-articular injections during surgery followed by continuous infusion, both with ropivacaine (567 mg). Ropivacaine plasma concentrations

  10. Tomographic Structural Changes of Retinal Layers after Internal Limiting Membrane Peeling for Macular Hole Surgery.

    Science.gov (United States)

    Faria, Mun Yueh; Ferreira, Nuno P; Cristóvao, Diana M; Mano, Sofia; Sousa, David Cordeiro; Monteiro-Grillo, Manuel

    2018-01-01

    To highlight tomographic structural changes of retinal layers after internal limiting membrane (ILM) peeling in macular hole surgery. Nonrandomized prospective, interventional study in 38 eyes (34 patients) subjected to pars plana vitrectomy and ILM peeling for idiopathic macular hole. Retinal layers were assessed in nasal and temporal regions before and 6 months after surgery using spectral domain optical coherence tomography. Total retinal thickness increased in the nasal region and decreased in the temporal region. The retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and inner plexiform layer (IPL) showed thinning on both nasal and temporal sides of the fovea. The thickness of the outer plexiform layer (OPL) increased. The outer nuclear layer (ONL) and outer retinal layers (ORL) increased in thickness after surgery in both nasal and temporal regions. ILM peeling is associated with important alterations in the inner retinal layer architecture, with thinning of the RNFL-GCL-IPL complex and thickening of OPL, ONL, and ORL. These structural alterations can help explain functional outcome and could give indications regarding the extent of ILM peeling, even though peeling seems important for higher rate of hole closure. © 2017 S. Karger AG, Basel.

  11. Measures of total stress-induced blood pressure responses are associated with vascular damage.

    Science.gov (United States)

    Nazzaro, Pietro; Seccia, Teresa; Vulpis, Vito; Schirosi, Gabriella; Serio, Gabriella; Battista, Loredana; Pirrelli, Anna

    2005-09-01

    The role of cardiovascular reactivity to study hypertension, and the assessment methods, are still controversial. We aimed to verify the association of hypertension and vascular damage with several measures of cardiovascular response. We studied 40 patients with normal-high (132 +/- 1/87 +/- 1 mm Hg) blood pressure (Group 1) and 80 untreated hypertensive subjects. Postischemic forearm vascular resistance (mFVR) served to differentiate hypertensive subjects (142 +/- 2/92 +/- 1 mm Hg v 143 +/- 2/94 +/- 2 mm Hg, P = NS) with a lower (Group 2) and higher (Group 3) hemodynamic index of vascular damage (4.8 +/- .05 v 6.3 +/- .09, P blood pressure, heart rate, forearm blood flow, and vascular resistance. Reactivity measures included: a) change from baseline, b) residualized score, c) cumulative change from baseline and residualized score, and d) total reactivity as area-under-the-curve (AUC), including changes occurring during baseline and recovery phases. The AUC of systolic blood pressure, diastolic blood pressure, and mFVR progressively increased in the groups (P AUC of SBP, DBP, and forearm blood flow and resistance demonstrated the highest (P AUC of SBP (beta = 0.634) and forearm blood flow (beta = -0.337) were predictive (P blood pressure stress response, as AUC, including baseline and recovery phases, was significantly better associated with hypertension and vascular damage than the other reactivity measures studied.

  12. Prevalence of generalized retinal dystrophy in Denmark

    DEFF Research Database (Denmark)

    Bertelsen, Mette; Jensen, Hanne; Bregnhøj, Jesper F

    2014-01-01

    of this study was to examine the prevalence and diagnostic spectrum of generalized retinal dystrophy in the Danish population. METHODS: A population-based cross-sectional study with data from the Danish Retinitis Pigmentosa Registry that comprises all patients in Denmark with generalized retinal......PURPOSE: Generalized retinal dystrophy is a frequent cause of visual impairment and blindness in younger individuals and a subject of new clinical intervention trials. Nonetheless, there are few nation-wide population-based epidemiological data of generalized retinal dystrophy. The purpose...... and chorioretinal dystrophies from the 19th century to the present. Among 3076 registered cases, the primary diagnosis of generalized retinal dystrophy was assessed by chart review, including fundus photographs and electroretinograms. Demographic data on the Danish population were retrieved from Statistics Denmark...

  13. Anomalous coagulation factors in non-arteritic anterior ischemic optic neuropathy with central retinal vein occlusion: A case report.

    Science.gov (United States)

    Kim, Ji Hong; Kang, Min Ho; Seong, Mincheol; Cho, Heeyoon; Shin, Yong Un

    2018-04-01

    Non-arteritic anterior ischemic optic neuropathy (NAION) is characterized by sudden, painless visual loss and optic disc edema. NAION occurs mainly in the presence of cardiovascular disease and hypercoagulability, mainly in patients over 50 years of age. We experienced a case of NAION associated with central retinal vein occlusion (CRVO) in a young man with no underlying disease. A 46-year-old man was referred to our clinic following a sudden loss of vision in his right eye. The patient exhibited no underlying disease and reported no ongoing medication. Significant visual loss and visual disturbance of the right eye were observed. The pupil of the right eye was enlarged and an afferent pupillary defect was observed. On fundus examination, retinal hemorrhage was observed in the peripheral retina; macular edema was observed in optical coherence tomography analysis. However, optic disc edema was not evident. No abnormal findings were found in routine blood tests for hypercoagulability. After 3 days of steroid intravenous injection, macular edema disappeared and visual acuity was improved, but optic disc edema began to appear. One week later, optic disc edema was evident and visual acuity was significantly reduced; thus, the patient was diagnosed with NAION. In fluorescein angiography, peripheral retinal ischemia was observed, suggesting that CRVO was complicated. Blood tests, including analysis of coagulation factors, were performed again, showing that coagulation factors IX and XI were increased. Anomalous coagulation factors in non-arteritic anterior ischemic optic neuropathy with central retinal vein occlusion. Systemic steroids were administered. One month later, optic disc edema and retinal hemorrhage gradually diminished and eventually disappeared; however, visual acuity did not recover. In young patients without underlying disease, cases of NAION require careful screening for coagulation disorders. Even if there is no abnormality in the test for routine

  14. Zingiber officinale attenuates retinal microvascular changes in diabetic rats via anti-inflammatory and antiangiogenic mechanisms

    Science.gov (United States)

    Dongare, Shirish; Mathur, Rajani; Saxena, Rohit; Mathur, Sandeep; Agarwal, Renu; Nag, Tapas C.; Srivastava, Sushma; Kumar, Pankaj

    2016-01-01

    Purpose Diabetic retinopathy is a common microvascular complication of long-standing diabetes. Several complex interconnecting biochemical pathways are activated in response to hyperglycemia. These pathways culminate into proinflammatory and angiogenic effects that bring about structural and functional damage to the retinal vasculature. Since Zingiber officinale (ginger) is known for its anti-inflammatory and antiangiogenic properties, we investigated the effects of its extract standardized to 5% 6-gingerol, the major active constituent of ginger, in attenuating retinal microvascular changes in rats with streptozotocin-induced diabetes. Methods Diabetic rats were treated orally with the vehicle or the ginger extract (75 mg/kg/day) over a period of 24 weeks along with regular monitoring of bodyweight and blood glucose and weekly fundus photography. At the end of the 24-week treatment, the retinas were isolated for histopathological examination under a light microscope, transmission electron microscopy, and determination of the retinal tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB), and vascular endothelial growth factor (VEGF) levels. Results Oral administration of the ginger extract resulted in significant reduction of hyperglycemia, the diameter of the retinal vessels, and vascular basement membrane thickness. Improvement in the architecture of the retinal vasculature was associated with significantly reduced expression of NF-κB and reduced activity of TNF-α and VEGF in the retinal tissue in the ginger extract–treated group compared to the vehicle-treated group. Conclusions The current study showed that ginger extract containing 5% of 6-gingerol attenuates the retinal microvascular changes in rats with streptozotocin-induced diabetes through anti-inflammatory and antiangiogenic actions. Although precise molecular targets remain to be determined, 6-gingerol seems to be a potential candidate for further investigation. PMID:27293376

  15. Early interventions to prevent retinal vasculopathy in diabetes: a review

    Directory of Open Access Journals (Sweden)

    Harrison WW

    2015-08-01

    Full Text Available Wendy W Harrison, Vladimir YevseyenkovArizona College of Optometry, Midwestern University, Glendale, AZ, USAAbstract: Diabetic eye disease is a public health concern in all areas of the world as a leading cause of blindness in the working aged to elderly populations. Diabetes damages the lining of the microvasculature throughout the body through prolonged exposure to hyperglycemic conditions. The ocular changes are progressive with very little recourse for improvement once damage begins. Current treatments for the eye focus mainly on the late stages of the disease when neovascularization or edema threatens sight. Early interventions for diabetic vasculopathy involve metabolic therapy to improve blood glucose and blood pressure control. Technology improvements have a large part to play in advancing diagnosis of diabetic eye disease. These new technologies offer both structural and functional means for assessment of retinal health. This review focuses on current treatments for diabetic eye disease at all stages with an emphasis on new and early interventions. It also details established and emerging technologies used for earlier detection of diabetic eye disease, which is vital to the development and approval of much needed treatments targeted at earlier stages of diabetic retinopathy. Possible future treatments should be aimed to prevent retinal vasculopathy from progressing. This review will explore current research on this topic and what is needed moving forward.Keywords: diabetes, diabetic retinopathy, vascular disease

  16. Novel method for edge detection of retinal vessels based on the model of the retinal vascular network and mathematical morphology

    Science.gov (United States)

    Xu, Lei; Zheng, Xiaoxiang; Zhang, Hengyi; Yu, Yajun

    1998-09-01

    Accurate edge detection of retinal vessels is a prerequisite for quantitative analysis of subtle morphological changes of retinal vessels under different pathological conditions. A novel method for edge detection of retinal vessels is presented in this paper. Methods: (1) Wavelet-based image preprocessing. (2) The signed edge detection algorithm and mathematical morphological operation are applied to get the approximate regions that contain retinal vessels. (3) By convolving the preprocessed image with a LoG operator only on the detected approximate regions of retinal vessels, followed by edges refining, clear edge maps of the retinal vessels are fast obtained. Results: A detailed performance evaluation together with the existing techniques is given to demonstrate the strong features of our method. Conclusions: True edge locations of retinal vessels can be fast detected with continuous structures of retinal vessels, less non- vessel segments left and insensitivity to noise. The method is also suitable for other application fields such as road edge detection.

  17. 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/.

  18. Clinically undetected retinal breaks causing retinal detachment: A review of options for management.

    Science.gov (United States)

    Gupta, Deepak; Ching, Jared; Tornambe, Paul E

    2017-08-12

    The successful detection of retinal breaks is a critical step in rhegmatogenous retinal detachment surgery in order to prevent persistent/recurrent retinal detachments. Not all retinal breaks causing retinal detachments are obvious. Retinal breaks may be obscured by opacities that are either anterior segment related, lens related, or posterior segment related. Rules to identify breaks based on subretinal fluid configuration are more difficult to apply in pseudophakic, aphakic, and scleral buckle encircled eyes-and in eyes with repeat detachments and those with proliferative vitreoretinopathy. Exudative detachments exhibit characteristic features and must be ruled out. A thorough clinical examination preoperatively is important even if a vitrectomy is planned. We review the incidence and causes of undetected breaks, along with preoperative/clinical issues that may hinder break detection. We review the literature with respect to investigative approaches and techniques that are available to the vitreoretinal surgeon when primary breaks remain clinically undetected during the preoperative examination. We broadly divide the surgical approaches into ones where the surgeon utilizes techniques to pursue actively a search for breaks versus adopting a purely speculative approach. Advantages and disadvantages of various techniques are appraised. Intuitively one might argue that an encircling scleral buckle combined with vitrectomy would give higher single operation success than pars plana vitrectomy alone because "undetected" retinal breaks would be addressed by a 360° plombage. We could not confirm this concept. Newer techniques, such as pars plana vitrectomy augmented with dye extrusion or endoscopic-assisted pars plana vitrectomy, show encouraging results. Technological advances such as intraoperative optical coherence tomography will also help to broaden the vitreoretinal surgeon's armamentarium. At this time, there is no gold standard in terms of the recommended

  19. Comparison of clinical characteristics of rhegmatogenous retinal detachment in pseudophakic and phakic Eyes

    International Nuclear Information System (INIS)

    Mukhtar, M. A.; Ishaq, M.; Mehboob, M. A.; Islam, Q. U.

    2017-01-01

    Objective: To compare the clinical profile, systemic risk factors, and characteristics of rhegmatogenous retinal detachment (RRD) in pseudophakic and phakic eyes. Study Design: Cross-sectional comparative study. Place and Duration of Study: Armed Forces Institute of Ophthalmology, Rawalpindi from August 2013 to August 2015. Methodology: A total of 164 eyes (96 pseudophakic patients and 68 phakic patients) with RRD were analyzed. Demographic data and associated known risk factors of study population were acquired. Retinal examination was done by single experienced retinal surgeon using indirect ophthalmoscopy for type of retinal break, location and number of retinal breaks, status of macula, morphological extent of RRD and retinal degenerations. All the findings were endorsed on a pre-devised proforma. Results: Mean age of patients in pseudophakic and phakic groups was 61.18+-10.39 and 59.27+-9.57 years, respectively. Frequency of male patients in pseudophakic and phakic groups was 74% and 57.4%, respectively. Mean axial length in pseudophakic and phakic groups was 23.13+-2.18 mm and 21.9+-2.01 mm, respectively. Difference in axial length and gender distribution between two groups was statistically significant (p < 0.05). Difference in frequency of patients with history of hypertension and myopia between two groups was statistically significant (p < 0.05). Characteristics of RRD (type, location and number of retinal breaks, macula status, and extent of RRD) between groups were not statistically significant. Conclusion: RRD is more common in pseudophakic patients with male gender, increased axial length, myopia, and hypertension. (author)

  20. Short-term poor glycemic control and retinal microvascular changes in pediatric Type 1 Diabetes patients in Singapore: a pilot study.

    Science.gov (United States)

    Li, Ling-Jun; Lamoureux, Ecosse; Wong, Tien Yin; Lek, Ngee

    2017-06-15

    Poor glycemic control in Type 1 Diabetes (T1D) patients is strongly associated with an increased risk of diabetes-related microvascular complications later in life, but it is unclear whether short period of poor glycemic control in children with T1D can cause evident microvascular morphological changes long before any pathological manifestation. Our study aimed to investigate the longitudinal association between poor glycemic control and subsequent changes in retinal microvasculature, in a pilot study of 55 pediatric T1D patients from Singapore after a one-year follow-up. This is a hospital-based, exposure-matched and retrospective longitudinal study. A total of 55 T1D patients were included from Singapore KK Women's and Children Hospital, 28 of whom had poor glycemic control (average glycated hemoglobin [HbA1c] ≥8% during the year) while the other 27 age- and gender-matched subjects had good glycemic control (HbA1c Singapore I Vessel Assessment [SIVA], version 4.0, Singapore Eye Research Institute, Singapore) and a spectrum of retinal vascular parameters (e.g. caliber, tortuosity, branching angle and fractal dimension) were measured quantitatively from 0.5 to 2.0 disc diameters. There was no significant difference in ethnicity, duration of T1D, blood pressure, body mass index (BMI) and low-density cholesterol lipoprotein (LDL) between the two groups. Retinal imaging was obtained at the end of 1 year of glycemic control assessment. In multiple linear regression adjusting for ethnicity, BMI, LDL and duration of T1D, patients with poor glycemic control tended to have marginally wider retinal arteriolar caliber (6.0 μm, 95% CI: -0.9, 12.8) and had significantly larger retinal arteriolar branching angle (10.1 degrees, 95% CI: 1.4, 18.9) compared with their age- and gender- matched counterparts with good glycemic control. Our findings showed that abnormal retinal microvascular morphology was evident in pediatric patients with T1D after one-year's poor glycemic

  1. Macular Retinal Vessel Oxygen Saturation Elevation in Chinese Central Serous Chorioretinopathy

    Directory of Open Access Journals (Sweden)

    Cheng Li

    2017-01-01

    Full Text Available Purpose. To evaluate the retinal vessel oxygen saturation in central serous chorioretinopathy (CSC cases among the Chinese. Methods. Relative oxygen saturation of retinal blood vessels was measured in 33 Chinese patients with single-eye CSC using the Oxymap T1 retinal oximeter. The contralateral eyes were the control. The mean saturation of the retinal arteriole (AS and venule (VS, arteriovenous difference (AVS, and arteriole and venule diameters (AD, VD was analyzed in the optic disc area and macular region. Results. In the optic disc area, the inferotemporal quadrant (TI AS (93.2 ± 10.2% and inferonasal quadrant (NI VS (61.3 ± 7.3% were higher in the affected eyes than in the contralateral eyes (88.7 ± 7.7% and 56.9 ± 6.5% and AVS in NI (36.7 ± 10.4% decreased compared to the contralateral eyes (41.5 ± 11.2%. The VD in TI was expanded (19.9 ± 2.5 pixels versus 18.1 ± 3.4 pixels. Around the macular region, AS was 93.6 ± 7.6%, higher than in the contralateral eyes (89.5 ± 6.3%. No other significant changes were found. Conclusions. AS increased in the TI, and VS decreased in the NI in the eyes with CSC. In addition, AS also increased around the macular region, suggesting that these are contributors to CSC pathophysiology.

  2. Incidence and Pattern of Retinal Detachment in a Tertiary Eye ...

    African Journals Online (AJOL)

    retinal detachment symptoms, the predisposing/precipitating factors and the need ... Sebastian N. N. Nwosu, Guinness Eye Center, PMB 1534, Onitsha, Anambra ... the temporal retina and are all associated with total ... Table 2 shows the ocular risk factors. ..... Olurin O. Refractive errors in Nigerians: A hospital clinic study.

  3. Retinal findings in membranoproliferative glomerulonephritis

    Directory of Open Access Journals (Sweden)

    Ahmad M. Mansour

    2017-09-01

    Conclusions and importance: Drusen remain the ocular stigmata for MPGN occuring at an early age. The retinal disease is progressive with gradual thickening of Bruch's membrane and occurrence of retinal pigment epithelium detachment.

  4. Risk Factors for Central and Branch Retinal Vein Occlusion: A Meta-Analysis of Published Clinical Data

    Directory of Open Access Journals (Sweden)

    Petr Kolar

    2014-01-01

    Full Text Available Retinal vein occlusion (RVO is a major cause of vision loss. Of the two main types of RVO, branch retinal vein occlusion (BRVO is 4 to 6 times more prevalent than central retinal vein occlusion (CRVO. A basic risk factor for RVO is advancing age. Further risk factors include systemic conditions like hypertension, arteriosclerosis, diabetes mellitus, hyperlipidemia, vascular cerebral stroke, blood hyperviscosity, and thrombophilia. A strong risk factor for RVO is the metabolic syndrome (hypertension, diabetes mellitus, and hyperlipidemia. Individuals with end-organ damage caused by diabetes mellitus and hypertension have greatly increased risk for RVO. Socioeconomic status seems to be a risk factor too. American blacks are more often diagnosed with RVO than non-Hispanic whites. Females are, according to some studies, at lower risk than men. The role of thrombophilic risk factors in RVO is still controversial. Congenital thrombophilic diseases like factor V Leiden mutation, hyperhomocysteinemia and anticardiolipin antibodies increase the risk of RVO. Cigarette smoking also increases the risk of RVO as do systemic inflammatory conditions like vasculitis and Behcet disease. Ophthalmic risk factors for RVO are ocular hypertension and glaucoma, higher ocular perfusion pressure, and changes in the retinal arteries.

  5. Retinal Prosthesis System for Advanced Retinitis Pigmentosa: A Health Technology Assessment Update

    Science.gov (United States)

    Lee, Christine; Tu, Hong Anh; Wells, David; Holubowich, Corinne

    2017-01-01

    Background Retinitis pigmentosa is a group of inherited disorders characterized by the degeneration of the photoreceptors in the retina, resulting in progressive vision loss. The Argus II system is designed to restore partial functional vision in patients with profound vision loss from advanced retinitis pigmentosa. At present, it is the only treatment option approved by Health Canada for this patient population. In June 2016, Health Quality Ontario published a health technology assessment of the Argus II retinal prosthesis system for patients with advanced retinitis pigmentosa. Based on that assessment, the Ontario Health Technology Advisory Committee recommended against publicly funding the Argus II system for this population. It also recommended that Health Quality Ontario re-evaluate the evidence in 1 year. The objective of this report was to examine new evidence published since the 2016 health technology assessment. Methods We completed a health technology assessment, which included an evaluation of clinical benefits and harms, value for money, and patient preferences related to the Argus II system. We performed a systematic literature search for studies published since the 2016 Argus II health technology assessment. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care, and we calculated incremental cost-effectiveness ratios over a 20-year time horizon. We also conducted a five-year budget impact analysis. Finally, we interviewed people with retinitis pigmentosa about their lived experience with vision loss, and with the Argus II system. Results Four publications from one multicentre international study were included in the clinical review. Patients showed significant improvements in visual function and functional outcomes with the Argus II system, and these outcomes were sustained up to a 5-year follow-up (moderate quality of evidence). The safety profile was generally acceptable. In

  6. [Single intravenous tranexamic acid dose to reduce blood loss in primary total knee replacement].

    Science.gov (United States)

    Sanz-Reig, J; Parra Ruiz, B; Ferrández Martínez, J; Martínez López, J F

    2016-01-01

    To evaluate the effectiveness and safety of a single intravenous dose of tranexamic acid in order to reduce blood loss in total knee replacement. Prospective observational study of the administration of tranexamic acid in patients undergoing primary total knee arthroplasty from November 2013 to February 2015, in which an autologous blood recovery system was used. The study included 98 patients, distributed into two groups of 49 patients according to whether or not they received intravenous tranexamic acid. The primary endpoint was the number of patients requiring autologous transfusion from the recovery system autologous blood recovery system. No drop-outs were recorded during follow-up. There were no significant differences between groups as regards the preoperative and hospital variables. The mean preoperative haemoglobin and haematocrit at 24 and 48 hours postoperatively were similar in both groups. The average volume of bleeding in the autologous blood recovery system and estimated average blood loss was lower in patients who had been administered tranexamic acid, with significant differences. No patients in the group that was administered tranexamic acid required blood autotransfusion. The transfusion rate was zero in the two groups. No adverse events related to the administration of tranexamic acid were recorded. Intravenous administration of tranexamic acid, according to the described protocol, has presented a non-autotransfusion or allo-transfusion rate of 100%, with no increased incidence of thrombotic events. Thus, its use in this group of patients is recommended. The indication should be individualized, its use justified in the patient medical records, and informed consent is mandatory. Copyright © 2015 SECOT. Published by Elsevier Espana. All rights reserved.

  7. Stem Cell-Based Therapeutic Applications in Retinal Degenerative Diseases.

    OpenAIRE

    Huang Yiming; Enzmann Volker; Ildstad Suzanne T

    2011-01-01

    Retinal degenerative diseases that target photoreceptors or the adjacent retinal pigment epithelium (RPE) affect millions of people worldwide. Retinal degeneration (RD) is found in many different forms of retinal diseases including retinitis pigmentosa (RP), age-related macular degeneration (AMD), diabetic retinopathy, cataracts, and glaucoma. Effective treatment for retinal degeneration has been widely investigated. Gene-replacement therapy has been shown to improve visual function in inheri...

  8. Retinal Cell Degeneration in Animal Models

    Directory of Open Access Journals (Sweden)

    Masayuki Niwa

    2016-01-01

    Full Text Available The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl2-induced, autoimmune (experimental autoimmune encephalomyelitis, mechanical stress (optic nerve crush-induced, light-induced and ischemia (transient retinal ischemia-induced. The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insight into the underlying mechanisms of the disease, and will facilitate the development of novel effective therapeutic drugs to treat retinal cell damage.

  9. [Tibolone's effect on retinal and ophthalmic arteries flowmetry].

    Science.gov (United States)

    Souza, Marco Aurélio Martins de; Geber, Selmo

    2008-11-01

    to evaluate the effect of tibolone use on doppler-velocimetric parameters of ophthalmic and retinal arteries. clinical, prospective, longitudinal, randomized, placebo-controlled, triple-blind study, in which among 100 menopausal women, 50 have used 2.5 mg of the active principle tibolone (Tib Group) and 50, placebo as a means to form the control-group (Plac Group). In the Tib Group, 44 of the 50 women returned after 84 days to finish the exams, and in the Plac Group, 47. The ophthalmic and retinal arteries were studied to determine the resistance index (RI), the pulsatility index (PI) and the systole/diastole ratio (S/D). Assessments have been done before and 84 days after medication. The t-Student test has been used for the comparison of means between the groups in independent samples, as well as for within-group comparisons in dependent samples. in both groups, the women's characteristics were similar in age, menopause duration, body mass index, arterial blood pressure, deliveries and cardiac rate. The Tib Group presented the following values in the ophthalmic artery: RI(pre)=0.71+/-0.05, RI(post)0.72+/-0.08 (p=0.43); PI(pre)=1.29+/-0.22, PI(post)=1.30+/-0.25 (p=0.4) and S/D(pre)=3.49+/-0.77, SD(post)=3.65+/-0.94 (p=0.32). In the retinal artery, the following values have been found: RI(pre)=0.67+/-0.09, RI(post)=0.69+/-0.10 (p=0.7); PI(pre)=1.20+/-0.29, PI(post)=1.22+/-0.3 (p=0.2) and SD(pre)=3.29+/-0.95, SD(post)=3.30+/-1.07 (p=0.3). Also, the tibolone and control groups did not show any significant difference in regard to the above indexes in the end of the study. the 2.5 mg dose of tibolone had no effect on the Doppler velocimetry indexes of the ophthalmic and retinal arteries.

  10. Tranexamic acid reduces blood loss and blood transfusions in primary total hip arthroplasty: a prospective randomized double-blind study in 40 patients

    DEFF Research Database (Denmark)

    Husted, Henrik; Blønd, Lars; Sonne-Holm, Stig

    2003-01-01

    INTRODUCTION: We performed a prospective, randomized, double-blind study on 40 patients scheduled for primary total hip arthroplasty due to arthrosis or osteonecrosis to determine the effect of tranexamic acid on per- and postoperative blood losses and on the number of blood transfusions needed....... PATIENTS AND METHODS: 40 patients were randomized to tranexamic acid (10 mg/kg given as a bolus intravenous injection, followed by a continuous infusion of 1 mg/kg/hour for 10 hours) or placebo (20 mL saline given intravenously) 15 minutes before the incision. We recorded the peroperative and postoperative...... blood losses at removal of the drain 24 hours after the operation and the number of blood transfusions. RESULTS: Patients receiving tranexamic acid had a mean peroperative blood loss of 480 mL versus 622 mL in patients receiving placebo (p = 0.3), a postoperative blood loss of 334 mL versus 609 mL (p...

  11. Novel cellular bouton structure activated by ATP in the vascular wall of porcine retinal arterioles.

    Science.gov (United States)

    Misfeldt, Mikkel Wölck; Aalkjaer, Christian; Simonsen, Ulf; Bek, Toke

    2010-12-01

    The retinal blood flow is regulated by the tone of resistance arterioles, which is influenced by purinergic compounds such as adenosine and adenosine 5'-triphosphate (ATP) released from the retinal tissue. However, it is unknown what cellular elements in the perivascular retina are responsible for the effect of purines on the tone of retinal arterioles. Porcine retinal arterioles were loaded with the calcium-sensitive fluorophore Oregon green. The vessels were mounted in a confocal myograph for simultaneous recordings of tone and calcium activity in cells of the vascular wall during stimulation with ATP and adenosine, with and without modifiers of these compounds. Additionally, immunohistochemistry was used to localize elements with calcium activity in the vascular wall. Hyperfluorescence indicating calcium activity was recorded in a population of abundant round boutons interspersed in a network of vimentin-positive processes located immediately external to the smooth muscle cell layer but internal to the perivascular glial cells. These structures showed calcium activity when the vessel was relaxed with ATP but not when it was relaxed with adenosine. Ryanodine reduced calcium activity in the boutons, whereas the ATP antagonist adenosine-5'-O-(α, β- methylene diphosphate) reduced calcium activity in both the boutons and vascular tone. The vasodilating effect of purines in porcine retinal tissue involves ATP-dependent calcium activity in a layer of cellular boutons located external to the vascular smooth muscle cells and internal to the perivascular glial cells.

  12. The Impact of Macronutrients on Retinal Microvasculature among Singapore Pregnant Women during the Mid-Late Gestation.

    Science.gov (United States)

    Li, Ling-Jun; Ong, Peng Guan; Colega, Marjorelee T; Han, Chad Yixian; Chen, Ling Wei; Man Eyn Kidd, Ryan; Lamoureux, Ecosse; Gluckman, Peter; Kwek, Kenneth; Chong, Yap Seng; Saw, Seang Mei; Godfrey, Keith M; Wong, Tien Yin; Chong Foong-Fong, Mary

    2016-01-01

    Imbalanced macronutrient intakes can induce impairment of endothelial and vascular function, and further lead to metabolic and cardiovascular disease. However, little is known about the influence of such diets on endothelial and vascular dysfunction in pregnant women, even though high-fat diet is a known risk for pregnancy complications such as gestational diabetes and pre-eclampsia. We aimed to assess the association between maternal macronutrient intakes (protein, fat and carbohydrates), dietary quality and retinal microvascular changes in a multi-ethnic Asian mother-offspring cohort. Pregnant women (n = 614) with singleton pregnancies were recruited during their first trimester from June 2009 to Sep 2010. Maternal diet quality and macronutrient intakes, expressed as a percentage of total energy during pregnancy, were ascertained using 24 hr recalls and 3 d food diaries at 26-28 weeks gestation. Retinal examination was completed at the same clinic visit. Dietary quality was assessed and scored using the Health Eating Index in Asian Pregnant women (HEI-AP), while macronutrients intakes ware expressed as percentages of total energy and further log transformed for analysis. Associations were examined cross-sectionally by substitution models with the use of multiple linear regression. In adjusted model, each 20 points decrease in HEI-AP score was associated with a significant increase of 1.70 μm (p<0.05) in retinal venular calibre. Each 0.1 log increase in percentage of total fat intake was associated with a significant increment of 1.84 μm (p<0.05) in retinal venular caliber. Additionally, each 0.1 log increase in percentage of mono-unsaturated fat intake was associated with an increment of 1.84 μm (p<0.01) in retinal venular caliber. In this cross-sectional study, we found that women with higher fat and lower protein intakes, and lower diet quality tended to have wider retinal venular caliber, which is suggestive of suboptimal microvasculature.

  13. Influence of Clinical Factors and Magnification Correction on Normal Thickness Profiles of Macular Retinal Layers Using Optical Coherence Tomography

    Science.gov (United States)

    Higashide, Tomomi; Ohkubo, Shinji; Hangai, Masanori; Ito, Yasuki; Shimada, Noriaki; Ohno-Matsui, Kyoko; Terasaki, Hiroko; Sugiyama, Kazuhisa; Chew, Paul; Li, Kenneth K. W.; Yoshimura, Nagahisa

    2016-01-01

    Purpose To identify the factors which significantly contribute to the thickness variabilities in macular retinal layers measured by optical coherence tomography with or without magnification correction of analytical areas in normal subjects. Methods The thickness of retinal layers {retinal nerve fiber layer (RNFL), ganglion cell layer plus inner plexiform layer (GCLIPL), RNFL plus GCLIPL (ganglion cell complex, GCC), total retina, total retina minus GCC (outer retina)} were measured by macular scans (RS-3000, NIDEK) in 202 eyes of 202 normal Asian subjects aged 20 to 60 years. The analytical areas were defined by three concentric circles (1-, 3- and 6-mm nominal diameters) with or without magnification correction. For each layer thickness, a semipartial correlation (sr) was calculated for explanatory variables including age, gender, axial length, corneal curvature, and signal strength index. Results Outer retinal thickness was significantly thinner in females than in males (sr2, 0.07 to 0.13) regardless of analytical areas or magnification correction. Without magnification correction, axial length had a significant positive sr with RNFL (sr2, 0.12 to 0.33) and a negative sr with GCLIPL (sr2, 0.22 to 0.31), GCC (sr2, 0.03 to 0.17), total retina (sr2, 0.07 to 0.17) and outer retina (sr2, 0.16 to 0.29) in multiple analytical areas. The significant sr in RNFL, GCLIPL and GCC became mostly insignificant following magnification correction. Conclusions The strong correlation between the thickness of inner retinal layers and axial length appeared to result from magnification effects. Outer retinal thickness may differ by gender and axial length independently of magnification correction. PMID:26814541

  14. Influence of Clinical Factors and Magnification Correction on Normal Thickness Profiles of Macular Retinal Layers Using Optical Coherence Tomography.

    Directory of Open Access Journals (Sweden)

    Tomomi Higashide

    Full Text Available To identify the factors which significantly contribute to the thickness variabilities in macular retinal layers measured by optical coherence tomography with or without magnification correction of analytical areas in normal subjects.The thickness of retinal layers {retinal nerve fiber layer (RNFL, ganglion cell layer plus inner plexiform layer (GCLIPL, RNFL plus GCLIPL (ganglion cell complex, GCC, total retina, total retina minus GCC (outer retina} were measured by macular scans (RS-3000, NIDEK in 202 eyes of 202 normal Asian subjects aged 20 to 60 years. The analytical areas were defined by three concentric circles (1-, 3- and 6-mm nominal diameters with or without magnification correction. For each layer thickness, a semipartial correlation (sr was calculated for explanatory variables including age, gender, axial length, corneal curvature, and signal strength index.Outer retinal thickness was significantly thinner in females than in males (sr2, 0.07 to 0.13 regardless of analytical areas or magnification correction. Without magnification correction, axial length had a significant positive sr with RNFL (sr2, 0.12 to 0.33 and a negative sr with GCLIPL (sr2, 0.22 to 0.31, GCC (sr2, 0.03 to 0.17, total retina (sr2, 0.07 to 0.17 and outer retina (sr2, 0.16 to 0.29 in multiple analytical areas. The significant sr in RNFL, GCLIPL and GCC became mostly insignificant following magnification correction.The strong correlation between the thickness of inner retinal layers and axial length appeared to result from magnification effects. Outer retinal thickness may differ by gender and axial length independently of magnification correction.

  15. Influence of Clinical Factors and Magnification Correction on Normal Thickness Profiles of Macular Retinal Layers Using Optical Coherence Tomography.

    Science.gov (United States)

    Higashide, Tomomi; Ohkubo, Shinji; Hangai, Masanori; Ito, Yasuki; Shimada, Noriaki; Ohno-Matsui, Kyoko; Terasaki, Hiroko; Sugiyama, Kazuhisa; Chew, Paul; Li, Kenneth K W; Yoshimura, Nagahisa

    2016-01-01

    To identify the factors which significantly contribute to the thickness variabilities in macular retinal layers measured by optical coherence tomography with or without magnification correction of analytical areas in normal subjects. The thickness of retinal layers {retinal nerve fiber layer (RNFL), ganglion cell layer plus inner plexiform layer (GCLIPL), RNFL plus GCLIPL (ganglion cell complex, GCC), total retina, total retina minus GCC (outer retina)} were measured by macular scans (RS-3000, NIDEK) in 202 eyes of 202 normal Asian subjects aged 20 to 60 years. The analytical areas were defined by three concentric circles (1-, 3- and 6-mm nominal diameters) with or without magnification correction. For each layer thickness, a semipartial correlation (sr) was calculated for explanatory variables including age, gender, axial length, corneal curvature, and signal strength index. Outer retinal thickness was significantly thinner in females than in males (sr2, 0.07 to 0.13) regardless of analytical areas or magnification correction. Without magnification correction, axial length had a significant positive sr with RNFL (sr2, 0.12 to 0.33) and a negative sr with GCLIPL (sr2, 0.22 to 0.31), GCC (sr2, 0.03 to 0.17), total retina (sr2, 0.07 to 0.17) and outer retina (sr2, 0.16 to 0.29) in multiple analytical areas. The significant sr in RNFL, GCLIPL and GCC became mostly insignificant following magnification correction. The strong correlation between the thickness of inner retinal layers and axial length appeared to result from magnification effects. Outer retinal thickness may differ by gender and axial length independently of magnification correction.

  16. Transcorneal Electrical Stimulation Therapy for Retinal Disease

    Science.gov (United States)

    2012-05-03

    Retinitis Pigmentosa; Macula Off; Primary Open Angle Glaucoma; Hereditary Macular Degeneration; Treated Retina Detachment; Retinal Artery Occlusion; Retinal Vein Occlusion; Non-Arthritic-Anterior-Ischemic Optic-Neuropathy; Hereditary Autosomal Dominant Optic Atrophy; Dry Age Related Macular Degeneration; Ischemic Macula Edema

  17. Transplantation of rat embryonic stem cell-derived retinal progenitor cells preserves the retinal structure and function in rat retinal degeneration.

    Science.gov (United States)

    Qu, Zepeng; Guan, Yuan; Cui, Lu; Song, Jian; Gu, Junjie; Zhao, Hanzhi; Xu, Lei; Lu, Lixia; Jin, Ying; Xu, Guo-Tong

    2015-11-09

    Degenerative retinal diseases like age-related macular degeneration (AMD) are the leading cause of blindness. Cell transplantation showed promising therapeutic effect for such diseases, and embryonic stem cell (ESC) is one of the sources of such donor cells. Here, we aimed to generate retinal progenitor cells (RPCs) from rat ESCs (rESCs) and to test their therapeutic effects in rat model. The rESCs (DA8-16) were cultured in N2B27 medium with 2i, and differentiated to two types of RPCs following the SFEBq method with modifications. For rESC-RPC1, the cells were switched to adherent culture at D10, while for rESC-RPC2, the suspension culture was maintained to D14. Both RPCs were harvested at D16. Primary RPCs were obtained from P1 SD rats, and some of them were labeled with EGFP by infection with lentivirus. To generate Rax::EGFP knock-in rESC lines, TALENs were engineered to facilitate homologous recombination in rESCs, which were cotransfected with the targeting vector and TALEN vectors. The differentiated cells were analyzed with live image, immunofluorescence staining, flow cytometric analysis, gene expression microarray, etc. RCS rats were used to mimic the degeneration of retina and test the therapeutic effects of subretinally transplanted donor cells. The structure and function of retina were examined. We established two protocols through which two types of rESC-derived RPCs were obtained and both contained committed retina lineage cells and some neural progenitor cells (NPCs). These rESC-derived RPCs survived in the host retinas of RCS rats and protected the retinal structure and function in early stage following the transplantation. However, the glia enriched rESC-RPC1 obtained through early and longer adherent culture only increased the b-wave amplitude at 4 weeks, while the longer suspension culture gave rise to evidently neuronal differentiation in rESC-RPC2 which significantly improved the visual function of RCS rats. We have successfully differentiated

  18. Densiron® 68 as an intraocular tamponade for complex inferior retinal detachments

    Directory of Open Access Journals (Sweden)

    Hussain RN

    2011-05-01

    Full Text Available Rumana N Hussain, Somnath BanerjeeLeicester Royal Infirmary, Leicester, UKIntroduction: Densiron® 68 is a high-density liquid used to tamponade inferior retinal detachments. We present a case series of 12 patients treated with Densiron as an intraocular tamponade agent.Methods: A retrospective analysis of 12 eyes in 12 patients was carried out. The primary endpoint was anatomic reattachment of the retina following removal of Densiron oil.Results: All patients had inferior detachments; 33% had associated proliferative vitreoretinopathy (PVR. Densiron was utilized as a primary agent in five patients (42%; the remaining patients had prior unsuccessful surgery for retinal reattachment, including pars plana vitrectomy, cryotherapy, laser, encirclement, gas (C3F8 or C2F6, or silicone oil. Eleven patients (91% had successful reattachment of the retina at 3 months following removal of Densiron; one patient had extensive PVR, total retinal detachment, preretinal macula fibrosis, and chronic hypotony, and surgical intervention was unsuccessful. Six patients (50% had raised intraocular pressure (IOP, resolving in the majority of cases following Densiron removal; two patients had long-term raised IOP requiring topical or surgical therapy. Of the six phakic patients, 50% developed significant cataract in the operated eye. Of those with successful retinal reattachment, visual outcome was variable, with 36% patients gaining two to four lines on Snellen, 27% remaining objectively the same, and 36% losing one to two lines.Conclusion: The anatomic success rate is high (91% in patients requiring Densiron tamponade for inferior retinal detachments with or without evidence of PVR either as a primary or secondary intervention. A common complication is raised IOP; however, this most often resolves following removal of the oil.Keywords: intraocular tamponade, silicone oil, retinal detachment, retinal reattachments

  19. Retinal Structure Measurements as Inclusion Criteria for Stem Cell-Based Therapies of Retinal Degenerations.

    Science.gov (United States)

    Jacobson, Samuel G; Matsui, Rodrigo; Sumaroka, Alexander; Cideciyan, Artur V

    2016-04-01

    We reviewed and illustrated the most optimal retinal structural measurements to make in stem cell clinical trials. Optical coherence tomography (OCT) and autofluorescence (AF) imaging were used to evaluate patients with severe visual loss from nonsyndromic and syndromic retinitis pigmentosa (RP), ABCA4-Stargardt disease, and nonneovascular age-related macular degeneration (AMD). Outer nuclear layer (ONL), rod outer segment (ROS) layer, inner retina, ganglion cell layer (GCL), and nerve fiber layer (NFL) thicknesses were quantified. All patients had severely reduced visual acuities. Retinitis pigmentosa patients had limited visual fields; maculopathy patients had central scotomas with retained peripheral function. For the forms of RP illustrated, there was detectable albeit severely reduced ONL across the scanned retina, and normal or hyperthick GCL and NFL. Maculopathy patients had no measurable ONL centrally; it became detectable with eccentricity. Some maculopathy patients showed unexpected GCL losses. Autofluorescence imaging illustrated central losses of RPE integrity. A hypothetical scheme to relate patient data with different phases of retinal remodeling in animal models of retinal degeneration was presented. Stem cell science is advancing, but it is not too early to open the discussion of criteria for patient selection and monitoring. Available clinical tools, such as OCT and AF imaging, can provide inclusion/exclusion criteria and robust objective outcomes. Accepting that early trials may not lead to miraculous cures, we should be prepared to know why-scientifically and clinically-so we can improve subsequent trials. We also must determine if retinal remodeling is an impediment to efficacy.

  20. Total contribution of airborne lead to blood lead.

    OpenAIRE

    Manton, W I

    1985-01-01

    A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone.

  1. Retinal Oximetry with Scanning Laser Ophthalmoscope in Infants.

    Directory of Open Access Journals (Sweden)

    Wouter B Vehmeijer

    Full Text Available Dual wavelength retinal oximetry has been developed for adults, but is not available for infants. Retinal oximetry may provide insight into the pathophysiology of oxygen-mediated diseases like retinopathy of prematurity. More insight in the oxygen metabolism of the retina in infants may provide valuable clues for better understanding and subsequent prevention or treatment of the disease. The measurements of oxygen saturation are obtained with two fundus images simultaneously captured in two different wavelengths of light. The comparison in light absorption of oxygenated and deoxygenated hemoglobin can be used to estimate the oxygen saturation within the retinal vessels by means of a software algorithm. This study aims to make retinal oximetry available for neonates. The first step towards estimating retinal oxygen saturation is determining the optical density ratio. Therefore, the purpose of this study is to image healthy newborn infants with a scanning laser ophthalmoscope and determine the optical density ratio for retinal oximetry analysis.Images of the retina of full-term healthy infants were obtained with an SLO, Optomap 200Tx (Optos, with two laser wavelengths (532nm and 633nm. The infant lay face down on the lower arm of the parent, while the parent supported the chest and chin with one hand, and stabilized the back with the other hand. No mydriatics or eyelid specula were used during this study. The images were analyzed with modified Oxymap Analyzer software for calculation of the Optical Density Ratio (ODR and vessel width. The ODR is inversely and approximately linearly related to the oxygen saturation. Measurements were included from the superotemporal vessel pair. A paired t-test was used for statistical analysis.Fifty-nine infants, (58% female, were included with mean gestational age of 40 ± 1.3 weeks (mean ± SD and mean post-natal age of 16 ± 4.8 days. A total of 28 images were selected for retinal oximetry analysis. The ODR was

  2. Retinal photography: A window into the cardiovascular-brain link in adolescent bipolar disorder.

    Science.gov (United States)

    Naiberg, Melanie R; Hatch, Jessica K; Selkirk, Beth; Fiksenbaum, Lisa; Yang, Victor; Black, Sandra; Kertes, Peter J; Goldstein, Benjamin I

    2017-08-15

    The burden of cardiovascular disease in bipolar disorder (BD) exceeds what can be explained by traditional cardiovascular risk factors (CVRFs), lifestyle, and/or medications. Moreover, neurocognitive deficits are a core feature of BD, and are also related to CVRFs. We examined retinal vascular photography, a proxy for cerebral microvasculature, in relation to CVRFs, peripheral microvascular function, and neurocognition among BD adolescents. Subjects were 30 adolescents with BD and 32 healthy controls (HC). Retinal photography was conducted using a Topcon TRC 50 DX, Type IA camera, following pupil dilation. Retinal arteriolar and venular caliber was measured, from which the arterio-venular ratio (AVR) was computed. All measures were conducted masked to participant diagnosis. Peripheral arterial tonometry measured endothelial function. Neurocognition was assessed using the Cambridge Neuropsychological Tests Automated Battery. AVR was not significantly different between groups (Cohen's d=0.18, p=0.103). Higher diastolic blood pressure (BP) was associated with lower (worse) AVR in BD (r=-0.441, p=0.015) but not HC (r=-0.192, p=0.293). Similarly, in the BD group only, higher (better) endothelial function was associated with higher AVR (r=0.375, p=0.041). Hierarchical regression models confirmed that, independent of covariates, retinal vascular caliber was significantly associated with diastolic BP and endothelial function in BD. Within the BD group, mood scores were significantly negatively correlated with AVR (β=-0.451, p=0.044). This study's limitations include a small sample size, a cross-sectional study design, and a heterogeneous sample. Retinal photography may offer unique insights regarding the cardiovascular and neurocognitive burden of BD. Larger longitudinal studies are warranted. Copyright © 2017. Published by Elsevier B.V.

  3. [Intra-Articular Application of Tranexamic Acid Significantly Reduces Blood Loss and Transfusion Requirement in Primary Total Knee Arthroplasty].

    Science.gov (United States)

    Lošťák, J; Gallo, J; Špička, J; Langová, K

    2016-01-01

    PURPOSE OF THE STUDY The aim of this prospective study was to investigate the effect of topical application of tranexamic acid (TXA, Exacyl) on the amount of post-operative blood loss, and blood transfusion requirement in patients undergoing primary total knee arthroplasty (TKA). Attention was paid to early complications potentially associated with TXA administration, such as haematoma, wound exudate, or knee swelling. In addition, the economic benefit of TXA treatment was also taken into account. MATERIAL AND METHODS The study included 238 patients (85 men and 153 women) who underwent primary total knee arthroplasty (TKA) at our department between January 2013 and November 2015. A group of 119 patients (41 men and 78 women) received intraarticular TXA injections according to the treatment protocol (TXA group). A control group matched in basic characteristics to the TXA group also consisted of 119 patients. The average age in the TXA group was 69.8 years, and the most frequent indication for TKA surgery was primary knee osteoarthritis (81.5%). In each patient, post-operative volume of blood lost from drains and total blood loss including hidden blood loss were recorded, as well as post-operative haemoglobin and haematocrit levels. On discharge of each patient from hospital, the size and site of a haematoma; wound exudate, if present after post-operative day 4; joint swelling; range of motion and early revision surgery, if performed, were evaluated. Requirements of analgesic drugs after surgery were also recorded. RESULTS In the TXA group, blood losses from drains were significantly lower than in the control group (456.7 ± 270.8 vs 640.5 ±448.2; p = 0.004). The median value for blood losses from drains was lower by 22% and the average value for total blood loss, including hidden losses, was also lower than in the control group (762.4 ± 345.2 ml vs 995.5 ± 457.3 ml). The difference in the total amount of blood loss between the two groups was significant (p = 0

  4. Total contribution of airborne lead to blood lead.

    Science.gov (United States)

    Manton, W I

    1985-01-01

    A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone. PMID:3970881

  5. Anti vascular endothelial growth factor (bevacizumab) in central retinal vein occlusion: an interventional case series

    International Nuclear Information System (INIS)

    Jan, S.; Khan, M.N.; Karim, S.; Khan, M.T.; Hussain, Z.; Khan, S.; Nazim, M.

    2010-01-01

    Vascular endothelial growth factor plays major role in ocular angio genesis and retinal edema production and is a step forward in the management of ocular neovascularization and retinal edematous pathologies. To determine the efficacy and safety of intra-vitreal Avastin (Bevacizumab) in cases having central retinal vein occlusion. All patients with central retinal occlusion occurring in the past 3 months and seen between the study period were included in the study. Diagnosis of central retinal vein occlusion was made clinically by slit lamp biomicroscopy with 78D examination Patients who had received any treatment for and eyes which already had developed Anterior Segment Neovascularization, Neovascularization elsewhere or Neovascularization on disc at presentation were excluded. Dose of 0.05 ml (1.25mg) of Avastin (Bevacizumab) was used as intra vitreal injection every month for 3 months in cases that presented within a month of occlusion and less injections were given in dose presenting later. Follow-up was done at 30th, 60th, 90th and 120th day after the onset of disease. Visual outcome was defined as Snellen's or LogMar Best Corrected Visual Acuity at final follow up, of 120th day, compared to the visual acuity at presentation. Data were analyzed by SPSS version 17. Total of 17 eyes of 17 patients were included in this study. Eleven (64.7%) patients were males while 6(35.3%) were females. Total of 40 intra-vitreal injections of Avastin were given to patients with a mean of 2.35 injections per eye. Good visual outcome was achieved in 10(58.8%) eyes, while 7(41.2%) had stable visual outcome. Mean initial Best Corrected Visual Acuity (LogMar) in all 17 eyes was 1.79(SD+0.87) which significantly improved to a mean of 1.18 (SD+0.77) at final follow up. Mean improvement in Best Corrected Visual Acuity (LogMar) after paired sample test in all patients at final follow up on day 120 was 0.61(SD+0.84). Retinal hemorrhages and macular edema decreased clinically on

  6. Safety of iPhone retinal photography.

    Science.gov (United States)

    Hong, Sheng Chiong; Wynn-Williams, Giles; Wilson, Graham

    2017-04-01

    With the advancement in mobile technology, smartphone retinal photography is becoming a popular practice. However, there is limited information about the safety of the latest smartphones used for retinal photography. This study aims to determine the photobiological risk of iPhone 6 and iPhone 6 plus when used in conjunction with a 20Diopter condensing lens for retinal photography. iPhone 6 and iPhone 6 plus (Apple, Cupertino, CA) were used in this study. The geometrical setup of the study was similar to the indirect ophthalmoscopy technique. The phone was set up at one end of the bench with its flash turned on at maximal brightness; a 20 Dioptre lens was placed 15 cm away from the phone. The light that passes through the lens was measured with a spectroradiometer and an illuminance probe at the other end to determine the spectral profile, spatial irradiance, radiant power emitted by the phone's flash. Trigonometric and lens formula were applied to determine the field of view and retinal surface in order to determine the weighted retinal irradiance and weighted retinal radiant exposure. Taking ocular transmission and the distribution of the beam's spatial irradiance into account, the weighted retinal irradiance is 1.40 mW/cm 2 and the weighted retinal radiant exposure is 56.25 mJ/cm 2 . The peak weighted foveal irradiance is 1.61 mW/cm 2 . Our study concluded that the photobiological risk posed by iPhone 6 indirect ophthalmoscopy was at least 1 order of magnitude below the safety limits set by the ISO15004-2.2.

  7. [Evaluation of the arterial blood flow parameters in the eye of myopic patients].

    Science.gov (United States)

    Mrugacz, Małgorzata; Bryl, Anna

    2013-04-01

    Myopia is a common refractive defect. Has a good vision from near and deterioration of vision with increasing distance. The main reason for its occurrence is too long axis of the eyeball. The consequence of elongation of the eyeball is the development of degenerative changes in the retina. Despite much research has failed to clearly identify the causes of degenerative changes in those short-sighted. The aim of the study was to evaluate the maximum and minimum speed in arterial blood vessels of the eye in people with myopia. The study included 70 patients (138 eyes), 53 women and 17 men, aged from 18 to 79 years, with myopia of -0.25 to -18.0 Dsph and length of the eyeball from 22.61 to 33.36 mm. Depending on the kind and the degree of the progress of degenerative changes, patients were divided in 4 groups: I - without degenerative changes on the fundus (n=32; K-23, M-9); II- with the short-sighted sickle (n=20; K-14, M-6); Ill - with the structure thinned down of the retina, accompanying the short-sighted sickle (n = 8; K-6, M-2); IV - with extensive choroidal-retina disappearances in the fundus (n = 10; K-7, M-3). In all individuals enrolled underwent Color Doppler ultrasound with apparatus SSA 770A Toshiba Aplio with linear probe frequency 12 MHz, judging maximum (Vmax) and minimum (Vmin) speed in the arteries of the eye: ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCA) located on the nasal and temporal side of the optic disc. The results were statistically analyzed. No statistically significant relationship between the nature of degenerative changes of the eye, and blood velocity in the OA. There was a increase in Vmax and Vmin blood in OA in Group IV, but these changes were not statistically significant. Statistically significant correlation was observed while in the CRA. With a decrease in Vmax and Vmin of blood flowing through a vessel exacerbation of retinal degeneration. Vmax and Vmin changes in the blood did

  8. Effect of total lymphoid irradiation and pretransplant blood transfusion on pancreatic islet allograft survival

    International Nuclear Information System (INIS)

    Mendez-Picon, G.; McGeorge, M.

    1983-01-01

    Total lymphoid irradiation (TLI) has been shown to have a strong immunosuppressive effect both experimentally and clinically. Pretransplant blood transfusions have also been shown to have a strong beneficial effect in the outcome of organ transplantation. A study was made of the effect of TLI and pretransplant blood transfusions, alone and in combination, as an immunosuppressive modality in the isolated pancreatic islet transplant in the rat model. Donor rats (Fischer RT1v1) were kept on a 50% DL-ethionine supplemented diet for 4-6 weeks prior to pancreas removal. Recipient rats (Lewis RT1) were made diabetics prior to transplantation by iv injection of streptozotocin (45 mg/kg). Transfusion protocol consisted of a biweekly transfusion of 2 ml of either donor specific or third party transfusions. Total lymphoid irradiation was carried out by daily administration of 200 rads during one week prior to transplantation. Transplantation of the isolated islets was performed by intraportal injection. Syngeneic transplant of one and a half donor pancreata in each recipient reverted the diabetic condition indefinitely (greater than 100 days). Untreated allogenic grafts had a mean survival time (MST) of 5.2 days. Total lymphoid irradiation in dosages of 800, 1000, and 1200 rads, as the only immunosuppressive regimen, prolonged the MST of allografts to 15.3, 16.5, and 21.8 days, respectively (P less than .05). Pretransplant third party blood transfusion had no effect on allograft survival (MST 6.0). When donor specific blood transfusions were given, the MST was prolonged to 25.3 days (P less than .05). When TLI was administered to recipients of donor specific transfusions, the MST of the allografts did not show any statistical significant difference when compared with untreated animals. This abrogation of the beneficial effect of specific blood transfusion was observed in all dosages of TLI employed: 800 rad (MST 3.0), 1000 rad (MST 8.0), 1200 rad (MST 5.18)

  9. [Effects of pressure induced retinal ischemia on ERG in rabbit].

    Science.gov (United States)

    Song, G; Yang, X; Zhang, Z; Zhang, D

    2001-12-01

    To observe the effects of pressure induced retinal ischemia on electroretinogram(ERG) in rabbit. Retinal ischemia was induced in rabbits by increasing intraocular pressure at 30 mmHg, 60 mmHg, 90 mmHg, 120 mmHg for 45 minutes, and retinal function was monitored by eletroretinography. There was no difference on ERG before or after the experiment both in 30 mmHg group and control one. In 60 mmHg pressure induced ischemia eyes, the amplitudes of the b-wave and OPs wave reduced significantly. Four hours after reperfusion, they were totally recovered. After an ischemic insult of 90 mmHg or 120 mmHg for 45 minutes, there was no response of ERG. Four hours later, the amplitudes of the b-wave and OPs wave were 66.912 +/- 20.157 and 16.423 +/- 3.965 the former, 38.852 +/- 23.438 and 8.610 +/- 12.090 the latter, respectively. These results suggest that higher intraocular pressure causes more severe retina ischemic damage, and less recovery ability.

  10. Functional Response of Tumor Vasculature to PaCO2: Determination of Total and Microvascular Blood Volume by MRI

    Directory of Open Access Journals (Sweden)

    Scott D. Packard

    2003-07-01

    Full Text Available In order to identify differences in functional activity, we compared the reactivity of glioma vasculature and the native cerebral vasculature to both dilate and constrict in response to altered PaCO2. Gliomas were generated by unilateral implantation of U87MGdEGFR human glioma tumor cells into the striatum of adult female athymic rats. Relative changes in total and microvascular cerebral blood volume were determined by steady state contrast agent-enhanced magnetic resonance imaging for transitions from normocarbia to hypercarbia and hypocarbia. Although hypercarbia induced a significant increase in both total and microvascular blood volume in normal brain and glioma, reactivity of glioma vasculature was significantly blunted in comparison to normal striatum; glioma total CBV increased by 0.6±0.1%/mm Hg CO2 whereas normal striatum increased by 1.5±0.2%/mm Hg CO2, (P < .0001, group t-test. Reactivity of microvascular blood volume was also significantly blunted. In contrast, hypocarbia decreased both total and microvascular blood volumes more in glioma than in normal striatum. These results indicate that cerebral blood vessels derived by tumor-directed angiogenesis do retain reactivity to CO2. Furthermore, reduced reactivity of tumor vessels to a single physiological perturbation, such as hypercarbia, should not be construed as a generalized reduction of functional activity of the tumor vascular bed.

  11. Automated detection of retinal disease.

    Science.gov (United States)

    Helmchen, Lorens A; Lehmann, Harold P; Abràmoff, Michael D

    2014-11-01

    Nearly 4 in 10 Americans with diabetes currently fail to undergo recommended annual retinal exams, resulting in tens of thousands of cases of blindness that could have been prevented. Advances in automated retinal disease detection could greatly reduce the burden of labor-intensive dilated retinal examinations by ophthalmologists and optometrists and deliver diagnostic services at lower cost. As the current availability of ophthalmologists and optometrists is inadequate to screen all patients at risk every year, automated screening systems deployed in primary care settings and even in patients' homes could fill the current gap in supply. Expanding screens to all patients at risk by switching to automated detection systems would in turn yield significantly higher rates of detecting and treating diabetic retinopathy per dilated retinal examination. Fewer diabetic patients would develop complications such as blindness, while ophthalmologists could focus on more complex cases.

  12. Advances in Retinal Optical Imaging

    Directory of Open Access Journals (Sweden)

    Yanxiu Li

    2018-04-01

    Full Text Available Retinal imaging has undergone a revolution in the past 50 years to allow for better understanding of the eye in health and disease. Significant improvements have occurred both in hardware such as lasers and optics in addition to software image analysis. Optical imaging modalities include optical coherence tomography (OCT, OCT angiography (OCTA, photoacoustic microscopy (PAM, scanning laser ophthalmoscopy (SLO, adaptive optics (AO, fundus autofluorescence (FAF, and molecular imaging (MI. These imaging modalities have enabled improved visualization of retinal pathophysiology and have had a substantial impact on basic and translational medical research. These improvements in technology have translated into early disease detection, more accurate diagnosis, and improved management of numerous chorioretinal diseases. This article summarizes recent advances and applications of retinal optical imaging techniques, discusses current clinical challenges, and predicts future directions in retinal optical imaging.

  13. Variation in Use of Blood Transfusion in Primary Total Hip and Knee Arthroplasties.

    Science.gov (United States)

    Menendez, Mariano E; Lu, Na; Huybrechts, Krista F; Ring, David; Barnes, C Lowry; Ladha, Karim; Bateman, Brian T

    2016-12-01

    There is growing clinical and policy emphasis on minimizing transfusion use in elective joint arthroplasty, but little is known about the degree to which transfusion rates vary across US hospitals. This study aimed to assess hospital-level variation in use of allogeneic blood transfusion in patients undergoing elective joint arthroplasty and to characterize the extent to which variability is attributable to differences in patient and hospital characteristics. The study population included 228,316 patients undergoing total knee arthroplasty (TKA) at 922 hospitals and 88,081 patients undergoing total hip arthroplasty (THA) at 606 hospitals from January 1, 2009 to December 31, 2011 in the Nationwide Inpatient Sample database, a 20% stratified sample of US community hospitals. The median hospital transfusion rates were 11.0% (interquartile range, 3.5%-18.5%) in TKA and 15.9% (interquartile range, 5.4%-26.2%) in THA. After fully adjusting for patient- and hospital-related factors using mixed-effects logistic regression models, the average predicted probability of blood transfusion use in TKA was 6.3%, with 95% of the hospitals having a predicted probability between 0.37% and 55%. For THA, the average predicted probability of blood transfusion use was 9.5%, with 95% of the hospitals having a predicted probability between 0.57% and 66%. Hospital transfusion rates were inversely associated with hospital procedure volume and directly associated with length of stay. The use of blood transfusion in elective joint arthroplasty varied widely across US hospitals, largely independent of patient case-mix and hospital characteristics. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Retinal shows its true colours

    DEFF Research Database (Denmark)

    Coughlan, N. J.A.; Adamson, B. D.; Gamon, L.

    2015-01-01

    Retinal is one of Nature's most important and widespread chromophores, exhibiting remarkable versatility in its function and spectral response, depending on its protein environment. Reliable spectroscopic and photochemical data for the isolated retinal molecule are essential for calibrating theor...

  15. Paediatric retinal detachment: aetiology, characteristics and outcomes.

    Science.gov (United States)

    McElnea, Elizabeth; Stephenson, Kirk; Gilmore, Sarah; O'Keefe, Michael; Keegan, David

    2018-01-01

    To provide contemporary data on the aetiology, clinical features and outcomes of paediatric retinal detachment. A retrospective review of all those under 16y who underwent surgical repair for retinal detachment at a single centre between the years 2008 and 2015 inclusive was performed. In each case the cause of retinal detachment, the type of detachment, the presence or absence of macular involvement, the number and form of reparative surgeries undertaken, and the surgical outcome achieved was recorded. Twenty-eight eyes of 24 patients, 15 (62.5%) of whom were male and 9 (37.5%) of whom were female, their mean age being 11.6y and range 2-16y developed retinal detachment over the eight year period studied. Trauma featured in the development of retinal detachment in 14 (50.0%) cases. Retinal detachment was associated with other ocular and/or systemic conditions in 11 (39.3%) cases. A mean of 3.0 procedures with a range of 1-9 procedures per patient were undertaken in the management of retinal detachment. Complex vitrectomy combined with scleral buckling or complex vitrectomy alone were those most frequently performed. Mean postoperative visual acuity was 1.2 logMAR with range 0.0-3.0 logMAR. In 22 of 26 (84.6%) cases which underwent surgical repair the retina was attached at last follow-up. Aggressive management of paediatric retinal detachment including re-operation increases the likelihood of anatomical success. In cases where the retinal detachment can be repaired by an external approach alone there is a more favourable visual outcome.

  16. Retrobulbar optic neuritis and rhegmatogenous retinal detachment in a fourteen-year-old girl with retinitis pigmentosa sine pigmento.

    Science.gov (United States)

    Hatta, M; Hayasaka, S; Kato, T; Kadoi, C

    2000-01-01

    A 14-year-old girl complained of a sudden decrease in right visual acuity. The patient had night blindness, a mottled retina but no pigments, extinguished scotopic electroretinographic response, central scotoma in the right eye and rhegmatogenous retinal detachment. She had initially received laser photocoagulation around the retinal tear and then corticosteroid therapy, cryoretinopexy and segmental buckling. Her right visual acuity increased to 1.0. The association of retinitis pigmentosa sine pigmento, retrobulbar optic neuritis and rhegmatogenous retinal detachment, as demonstrated in our patient, may be uncommon. Copyright 2000 S. Karger AG, Basel

  17. Concentration of total proteins in blood plasma of chickens hatched from irradiated eggs with low dose gamma radiation

    International Nuclear Information System (INIS)

    Vilic, M.; Kraljevic, P.; Miljanic, S.; Simpraga, M.

    2005-01-01

    It is known that low-dose ionising radiation may have stimulating effects on chickens. Low doses may also cause changes in the concentration of blood plasma total proteins, glucose and cholesterol in chickens. This study investigates the effects of low dose gamma-radiation on the concentration of total proteins in the blood plasma of chickens hatched from eggs irradiated with a dose of 0.15 Gy on incubation days 7 and 19. Results were compared with the control group (chickens hatched from non-irradiated eggs). After hatching, all other conditions were the same for both groups. Blood samples were drawn from the heart, and later from the wing vein on days 1, 3, 5, 7,10, 20, 30 and 42. The concentration of total proteins was determined spectrophotometrically using Boehringer Mannheim GmbH optimised kits. The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 7 showed a statistically significant decrease on the sampling day 3 (P less than 0.05) and 7 (P less than 0.01). The concentration of total proteins in blood plasma in chickens hatched from eggs irradiated with 0.15 Gy on incubation day 19 showed a statistically significant increase only on sampling day 1 (P less than 0.05). These results suggest that exposure of eggs to 0.15 Gy of gamma-radiation on the 7th and 19th day of incubation could produce different effects on the protein metabolism in chickens.(author)

  18. Thrombophilic screening in retinal artery occlusion patients

    Directory of Open Access Journals (Sweden)

    Valeria Nagy

    2008-10-01

    Full Text Available Valeria Nagy1, Lili Takacs1, Zita Steiber1, György Pfliegler2, Andras Berta11Department of Ophthalmology, 2Division of Rare Diseases, University of Debrecen Medical and Health Science Center, Debrecen, HungaryBackground: Retinal artery occlusion (RAO is an ischemic vascular damage of the retina, which frequently leads to sudden, mostly irreversible loss of vision. In this study, blood thrombophilic factors as well as cardiovascular risk factors were investigated for their relevance to this pathology. Thrombophilic risk factors so far not evaluated were included in the study.Patients and methods: 28 RAO patients and 81 matched control subjects were examined. From blood samples, protein C, protein S, antithrombinopathy, and factor V (Leiden mutation (FV, factor II gene polymorphism, factor VIII C level, plasminogen activity, lipoprotein(a and fibrinogen levels, hyperhomocysteinemia and presence of anticardiolipin – antiphospholipid antibodies were investigated. Possibly relevant pathologies such as diabetes mellitus, hypertension, and ischemic heart disease were also registered. Statistical analysis by logistic regression was performed with 95% confidence intervals.Results: In the group of patients with RAO only the incidence of hypertension (OR: 3.33, 95% CI: 1.30–9.70, p = 0.014 as an average risk factor showed significant difference, but thrombophilic factors such as hyperfibrinogenemia (OR: 2.9, 95% CI: 1.29–6.57, p = 0.010 and the presence of FV (Leiden mutation (OR: 3.9, 95% CI: 1.43–10.96, p = 0.008 increased the chances of developing this disease.Conclusions: Our results support the assumption that thrombophilia may contribute to the development of RAO besides vascular damage due to the presence of cardiovascular risk factors. Further studies are needed, however, to justify the possible use of secondary prophylaxis in form of anticoagulant/antiplatelet therapy.Keywords: retinal arterial occlusion, risk factors, thrombophilia

  19. Genomic analysis of mouse retinal development.

    Directory of Open Access Journals (Sweden)

    Seth Blackshaw

    2004-09-01

    Full Text Available The vertebrate retina is comprised of seven major cell types that are generated in overlapping but well-defined intervals. To identify genes that might regulate retinal development, gene expression in the developing retina was profiled at multiple time points using serial analysis of gene expression (SAGE. The expression patterns of 1,051 genes that showed developmentally dynamic expression by SAGE were investigated using in situ hybridization. A molecular atlas of gene expression in the developing and mature retina was thereby constructed, along with a taxonomic classification of developmental gene expression patterns. Genes were identified that label both temporal and spatial subsets of mitotic progenitor cells. For each developing and mature major retinal cell type, genes selectively expressed in that cell type were identified. The gene expression profiles of retinal Müller glia and mitotic progenitor cells were found to be highly similar, suggesting that Müller glia might serve to produce multiple retinal cell types under the right conditions. In addition, multiple transcripts that were evolutionarily conserved that did not appear to encode open reading frames of more than 100 amino acids in length ("noncoding RNAs" were found to be dynamically and specifically expressed in developing and mature retinal cell types. Finally, many photoreceptor-enriched genes that mapped to chromosomal intervals containing retinal disease genes were identified. These data serve as a starting point for functional investigations of the roles of these genes in retinal development and physiology.

  20. Which Route of Tranexamic Acid Administration is More Effective to Reduce Blood Loss Following Total Knee Arthroplasty?

    Science.gov (United States)

    Keyhani, Sohrab; Esmailiejah, Ali Akbar; Abbasian, Mohammad Reza; Safdari, Farshad

    2016-01-01

    The most appropriate route of tranexamic acid administration is controversial. In the current study, we compared the efficacy of intravenous (IV) and topical intra-articular tranexamic acid in reducing blood loss and transfusion rate in patients who underwent primary total knee arthroplasty. One hundred twenty 120 patients were scheduled to undergo primary total knee arthroplasty. Patients were randomly allocated to three equal groups: IV tranexamic acid (500 mg), topical tranexamic acid (3 g in 100 mL normal saline) and the control. In the topical group, half of the volume was used to irrigate the joint and the other half was injected intra-articularly. The volume of blood loss, hemoglobin (Hb) level at 24 hours postoperative, and rate of transfusion was compared between groups. The blood loss and Hb level were significantly greater and lower in the control group, respectively (P=0.031). Also, the rate of transfusion was significantly greater in the control group (P=0.013). However, IV and topical groups did not differ significantly in terms of measured variables. No patient experienced a thromboembolic event in our study. Tranexamic acid is a useful antifibrinolytic drug to reduce postoperative blood loss, Hb drop, and rate of blood transfusion in patients undergoing total knee arthroplasty. The route of tranexamic acid administration did not affect the efficacy and safety.

  1. Vitreo-retinal eye surgery robot : sustainable precision

    NARCIS (Netherlands)

    Meenink, H.C.M.

    2011-01-01

    Vitreo-retinal eye surgery encompasses the surgical procedures performed on the vitreous humor and the retina. A procedure typically consists of the removal of the vitreous humor, the peeling of a membrane and/or the repair of a retinal detachment. Vitreo-retinal surgery is performed minimal

  2. Astrocytes and Müller Cell Alterations During Retinal Degeneration in a Transgenic Rat Model of Retinitis Pigmentosa

    Science.gov (United States)

    Fernández-Sánchez, Laura; Lax, Pedro; Campello, Laura; Pinilla, Isabel; Cuenca, Nicolás

    2015-01-01

    Purpose: Retinitis pigmentosa includes a group of progressive retinal degenerative diseases that affect the structure and function of photoreceptors. Secondarily to the loss of photoreceptors, there is a reduction in retinal vascularization, which seems to influence the cellular degenerative process. Retinal macroglial cells, astrocytes, and Müller cells provide support for retinal neurons and are fundamental for maintaining normal retinal function. The aim of this study was to investigate the evolution of macroglial changes during retinal degeneration in P23H rats. Methods: Homozygous P23H line-3 rats aged from P18 to 18 months were used to study the evolution of the disease, and SD rats were used as controls. Immunolabeling with antibodies against GFAP, vimentin, and transducin were used to visualize macroglial cells and cone photoreceptors. Results: In P23H rats, increased GFAP labeling in Müller cells was observed as an early indicator of retinal gliosis. At 4 and 12 months of age, the apical processes of Müller cells in P23H rats clustered in firework-like structures, which were associated with ring-like shaped areas of cone degeneration in the outer nuclear layer. These structures were not observed at 16 months of age. The number of astrocytes was higher in P23H rats than in the SD matched controls at 4 and 12 months of age, supporting the idea of astrocyte proliferation. As the disease progressed, astrocytes exhibited a deteriorated morphology and marked hypertrophy. The increase in the complexity of the astrocytic processes correlated with greater connexin 43 expression and higher density of connexin 43 immunoreactive puncta within the ganglion cell layer (GCL) of P23H vs. SD rat retinas. Conclusions: In the P23H rat model of retinitis pigmentosa, the loss of photoreceptors triggers major changes in the number and morphology of glial cells affecting the inner retina. PMID:26733810

  3. Astrocytes and Müller cells changes during retinal degeneration in a transgenic rat model of retinitis pigmentosa.

    Directory of Open Access Journals (Sweden)

    Laura eFernández-Sánchez

    2015-12-01

    Full Text Available Purpose: Retinitis pigmentosa includes a group of progressive retinal degenerative diseases that affect the structure and function of photoreceptors. Secondarily to the loss of photoreceptors, there is a reduction in retinal vascularization, which seems to influence the cellular degenerative process. Retinal macroglial cells, astrocytes and Müller cells provide support for retinal neurons and are fundamental for maintaining normal retinal function. The aim of this study was to investigate the evolution of macroglial changes during retinal degeneration in P23H rats. Methods: Homozygous P23H line-3 rats aged from P18 to 18 months were used to study the evolution of the disease, and SD rats were used as controls. Immunolabeling with antibodies against GFAP, vimentin, and transducin were used to visualize macroglial cells and cone photoreceptors. Results: In P23H rats, increased GFAP labeling in Müller cells was observed as an early indicator of retinal gliosis. At 4 and 12 months of age, the apical processes of Müller cells in P23H rats clustered in firework-like structures, which were associated with ring-like shaped areas of cone degeneration in the outer nuclear layer. These structures were not observed at 16 months of age. The number of astrocytes was higher in P23H rats than in the SD matched controls at 4 and 12 months of age, supporting the idea of astrocyte proliferation. As the disease progressed, astrocytes exhibited a deteriorated morphology and marked hypertrophy. The increase in the complexity of the astrocytic processes correlated with greater connexin 43 expression and higher density of connexin 43 immunoreactive puncta within the ganglion cell layer of P23H versus SD rat retinas. Conclusions: In the P23H rat model of retinitis pigmentosa, the loss of photoreceptors triggers major changes in the number and morphology of glial cells affecting the inner retina.

  4. Detection and classification of retinal lesions for grading of diabetic retinopathy.

    Science.gov (United States)

    Usman Akram, M; Khalid, Shehzad; Tariq, Anam; Khan, Shoab A; Azam, Farooque

    2014-02-01

    Diabetic Retinopathy (DR) is an eye abnormality in which the human retina is affected due to an increasing amount of insulin in blood. The early detection and diagnosis of DR is vital to save the vision of diabetes patients. The early signs of DR which appear on the surface of the retina are microaneurysms, haemorrhages, and exudates. In this paper, we propose a system consisting of a novel hybrid classifier for the detection of retinal lesions. The proposed system consists of preprocessing, extraction of candidate lesions, feature set formulation, and classification. In preprocessing, the system eliminates background pixels and extracts the blood vessels and optic disc from the digital retinal image. The candidate lesion detection phase extracts, using filter banks, all regions which may possibly have any type of lesion. A feature set based on different descriptors, such as shape, intensity, and statistics, is formulated for each possible candidate region: this further helps in classifying that region. This paper presents an extension of the m-Mediods based modeling approach, and combines it with a Gaussian Mixture Model in an ensemble to form a hybrid classifier to improve the accuracy of the classification. The proposed system is assessed using standard fundus image databases with the help of performance parameters, such as, sensitivity, specificity, accuracy, and the Receiver Operating Characteristics curves for statistical analysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. [Indications for Retinal Laser Therapy Revisited].

    Science.gov (United States)

    Enders, P; Schaub, F; Fauser, S

    2017-02-10

    Background Laser therapy is an important treatment option in retinal diseases, especially in cases of vascular involvement. Most approaches are based on coagulation of retinal structures. As there is increasing use of agents targetting vascular endothelial growth factor in the treatment of macular diseases, indications for the use of laser treatment need to be reviewed carefully, especially with respect to their significance in first line therapy. This article explains recent strategies and treatment protocols. Materials and Methods Review of current literature in PubMed as well as synopsis of relevant guidelines. Results and Conclusion Retinal laser therapy is still widely used within retinal opthalmology and covers a large spectrum of indications. Despite the success of medical approaches, retinal laser therapy remains an indispensable treatment option for proliferative diabetic retinopathy, central or peripheral vein occlusion and less frequent pathologies, such as retinopathy of prematurity or Coats's disease. Georg Thieme Verlag KG Stuttgart · New York.

  6. Effects of simvastatin on CAT-1-mediated arginine transport and NO level under high glucose conditions in conditionally immortalized rat inner blood-retinal barrier cell lines (TR-iBRB).

    Science.gov (United States)

    Tun, Temdara; Kang, Young-Sook

    2017-05-01

    Hyperglycemia causes the breakdown of the blood-retinal barrier by impairing endothelial nitric oxide synthase (eNOS) function. Statins have many pleiotropic effects such as improving endothelial barrier permeability and increasing eNOS mRNA stability. The objective of this study was to determine effect of simvastatin on l-arginine transport and NO production under high-glucose conditions in conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB). Changes in l-arginine transport uptake and, expression levels of cationic amino acid transporter 1 (CAT-1) and eNOS mRNA were investigated after pre-treatment with simvastatin and NOS inhibitors (l-NMMA and l-NAME) under high-glucose conditions using TR-iBRB, an in vitro model of iBRB. The NO level released from TR-iBRB cells was examined using Griess reagents. Under high glucose conditions, [ 3 H]l-arginine uptake was decreased in TR-iBRB cells. Simvastatin pretreatment elevated [ 3 H]l-arginine uptake, the expression levels of CAT-1 and eNOS mRNA, and NO production under high-glucose conditions. Moreover, the co-treatment with simvastatin and NOS inhibitors reduced [ 3 H]l-arginine uptake compared to pretreatment with simvastatin alone. Our results suggest that, in the presence of high-glucose levels, increased l-arginine uptake due to simvastatin treatment was associated with increased CAT-1 and eNOS mRNA levels, leading to higher NO production in TR-iBRB cells. Thus, simvastatin might be a good modulator for diabetic retinopathy therapy by increasing of the l-arginine uptake and improving endothelial function in retinal capillary endothelial cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Retinitis pigmentosa

    Directory of Open Access Journals (Sweden)

    Hamel Christian

    2006-10-01

    Full Text Available Abstract Retinitis pigmentosa (RP is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Prevalence of non syndromic RP is approximately 1/4,000. The most common form of RP is a rod-cone dystrophy, in which the first symptom is night blindness, followed by the progressive loss in the peripheral visual field in daylight, and eventually leading to blindness after several decades. Some extreme cases may have a rapid evolution over two decades or a slow progression that never leads to blindness. In some cases, the clinical presentation is a cone-rod dystrophy, in which the decrease in visual acuity predominates over the visual field loss. RP is usually non syndromic but there are also many syndromic forms, the most frequent being Usher syndrome. To date, 45 causative genes/loci have been identified in non syndromic RP (for the autosomal dominant, autosomal recessive, X-linked, and digenic forms. Clinical diagnosis is based on the presence of night blindness and peripheral visual field defects, lesions in the fundus, hypovolted electroretinogram traces, and progressive worsening of these signs. Molecular diagnosis can be made for some genes, but is not usually performed due to the tremendous genetic heterogeneity of the disease. Genetic counseling is always advised. Currently, there is no therapy that stops the evolution of the disease or restores the vision, so the visual prognosis is poor. The therapeutic approach is restricted to slowing down the degenerative process by sunlight protection and vitaminotherapy, treating the complications (cataract and macular edema, and helping patients to cope with the social and psychological impact of blindness. However, new therapeutic strategies are emerging from intensive research (gene therapy, neuroprotection, retinal prosthesis.

  8. Visual Acuity is Related to Parafoveal Retinal Thickness in Patients with Retinitis Pigmentosa and Macular Cysts

    Science.gov (United States)

    Brockhurst, Robert J.; Gaudio, Alexander R.; Berson, Eliot L.

    2008-01-01

    Purpose To quantify the prevalence and effect on visual acuity of macular cysts in a large cohort of patients with retinitis pigmentosa. Methods In 316 patients with typical forms of retinitis pigmentosa, we measured visual acuities with Early Treatment Diabetic Retinopathy Study (ETDRS) charts, detected macular cysts with optical coherence tomography (OCT), and quantified retinal thicknesses by OCT. We used the FREQ, LOGISTIC, and GENMOD procedures of SAS to evaluate possible risk factors for cyst prevalence and the MIXED procedure to quantify the relationships of visual acuity to retinal thickness measured at different locations within the macula. Results We found macular cysts in 28% of the patients, 40% of whom had cysts in only one eye. Macular cysts were seen most often in patients with dominant disease and not at all in patients with X-linked disease (p = 0.006). In eyes with macular cysts, multiple regression analysis revealed that visual acuity was inversely and independently related to retinal thickness at the foveal center (p = 0.038) and within a ring spanning an eccentricity of 5° to 10° from the foveal center (p = 0.004). Conclusions Macular cysts are a common occurrence in retinitis pigmentosa, especially among patients with dominantly-inherited disease. Visual acuity is influenced by edema in the parafovea, as well as in the fovea. PMID:18552390

  9. ACCELERATED ONSET OF RETINAL TOXICITY FROM HYDROXYCHLOROQUINE USE WITH CONCOMITANT BREAST CANCER THERAPY.

    Science.gov (United States)

    Sharma, Aman; Maiz, Alejandra M; Tucker, William R; Cukras, Catherine

    2018-05-16

    To report a case of accelerated retinal toxicity due to hydroxychloroquine (HCQ) use for treatment of Sjögren syndrome in a patient treated with concomitant chemotherapy for breast cancer. Observational case report. A 56-year-old white woman using 400 mg HCQ (7.1 mg/kg real body weight) daily for a total of 2 years and 10 months for treatment of Sjögren syndrome with concomitant use of docetaxel and cyclophosphamide therapy (21-day cycle, 4 cycles) followed by anastrozole for breast cancer, presented with visual complaints and findings of severe HCQ toxicity. Concomitant breast cancer therapy may have a synergistic effect with HCQ leading to accelerated retinal toxicity. As such potential acceleration is poorly understood, patients on HCQ who are treated with concomitant chemotherapy should be considered for more frequent retinal screenings to maximize safety and preservation of vision.

  10. Paediatric retinal detachment: aetiology, characteristics and outcomes

    Directory of Open Access Journals (Sweden)

    Elizabeth McElnea

    2018-02-01

    Full Text Available AIM: To provide contemporary data on the aetiology, clinical features and outcomes of paediatric retinal detachment. METHODS: A retrospective review of all those under 16y who underwent surgical repair for retinal detachment at a single centre between the years 2008 and 2015 inclusive was performed. In each case the cause of retinal detachment, the type of detachment, the presence or absence of macular involvement, the number and form of reparative surgeries undertaken, and the surgical outcome achieved was recorded. RESULTS: Twenty-eight eyes of 24 patients, 15 (62.5% of whom were male and 9 (37.5% of whom were female, their mean age being 11.6y and range 2-16y developed retinal detachment over the eight year period studied. Trauma featured in the development of retinal detachment in 14 (50.0% cases. Retinal detachment was associated with other ocular and/or systemic conditions in 11 (39.3% cases. A mean of 3.0 procedures with a range of 1-9 procedures per patient were undertaken in the management of retinal detachment. Complex vitrectomy combined with scleral buckling or complex vitrectomy alone were those most frequently performed. Mean postoperative visual acuity was 1.2 logMAR with range 0.0-3.0 logMAR. In 22 of 26 (84.6% cases which underwent surgical repair the retina was attached at last follow-up. CONCLUSION: Aggressive management of paediatric retinal detachment including re-operation increases the likelihood of anatomical success. In cases where the retinal detachment can be repaired by an external approach alone there is a more favourable visual outcome.

  11. 10B-NMR determination of 10B-BPA, 10B-BPA–fructose complex and total 10B in blood for BNCT

    International Nuclear Information System (INIS)

    Yoshino, K.; Yabe, T.; Hattori, T.; Saito, K.; Ishikawa, A.; Ohki, H.

    2014-01-01

    First spontaneous, noninvasive determination method of 10 B-BPA, 10 B-BPA–fructose complex, and total 10 B in blood is described. 10 B-NMR measurement with 100,000 FT accumulation enables us to obtain the result within 100 min/sample. The detection limits for the simultaneous analysis were 3 ppm, 3 ppm and 6 ppm for 10 B-BPA, 10 B-BPA–fructose complex and total 10 B respectively in this study. By this method, we can actually discuss behavior of the 10 B-BPA–fructose complex in blood. - Highlights: • First 10 B-NMR determination of 10 B-BPA and 10 B-BPA–fructose complex in blood. • Total 10 B concentration in blood could be obtained by this method • The detection limit was 3 ppm for total 10 B

  12. A method for volumetric retinal tissue oxygen tension imaging.

    Science.gov (United States)

    Felder, Anthony E; Wanek, Justin; Teng, Pang-Yu; Blair, Norman P; Shahidi, Mahnaz

    2018-01-01

    Inadequate retinal oxygenation occurs in many vision-threatening retinal diseases, including diabetic retinopathy, retinal vascular occlusions, and age-related macular degeneration. Therefore, techniques that assess retinal oxygenation are necessary to understand retinal physiology in health and disease. The purpose of the current study is to report a method for the three-dimensional (3D) imaging of retinal tissue oxygen tension (tPO 2 ) in rats. Imaging was performed in Long Evans pigmented rats under systemic normoxia (N = 6) or hypoxia (N = 3). A vertical laser line was horizontally scanned on the retina and a series of optical section phase-delayed phosphorescence images were acquired. From these images, phosphorescence volumes at each phase delay were constructed and a 3D retinal tPO 2 volume was generated. Retinal tPO 2 volumes were quantitatively analyzed by generating retinal depth profiles of mean tPO 2 (M tPO2 ) and the spatial variation of tPO 2 (SV tPO2 ). The effects of systemic condition (normoxia/hypoxia) and retinal depth on M tPO2 and SV tPO2 were determined by mixed linear model. Each 3D retinal tPO 2 volume was approximately 500 × 750 × 200 μm (horizontal × vertical × depth) and consisted of 45 en face tPO 2 images through the retinal depth. M tPO2 at the chorioretinal interface was significantly correlated with systemic arterial oxygen tension (P = 0.007; N = 9). There were significant effects of both systemic condition and retinal depth on M tPO2 and SV tPO2 , such that both were lower under hypoxia than normoxia and higher in the outer retina than inner retina (P < 0.001). For the first time, 3D imaging of retinal tPO 2 was demonstrated, with potential future application for assessment of physiological alterations in animal models of retinal diseases.

  13. The surface morphology of retinal breaks and lattice retinal degeneration. A scanning electron microscopic study.

    Science.gov (United States)

    Robinson, M R; Streeten, B W

    1986-02-01

    In 14 of 110 eye bank eyes, lesions characteristic of peripheral retinal surface pathology were examined by scanning electron microscopy (SEM). These included operculated and flap tears, trophic round holes, lattice degeneration with holes, and paravascular retinal "pitting" degeneration. By SEM, the edges of the retinal breaks were covered by smooth cellular membranes, merging peripherally with a meshwork of vitreous fibrils. The membrane cells had poorly defined borders, a pitted surface, and variable numbers of microvilli consistent with glia. Lattice surfaces and foci of paravascular retinal degeneration were covered by similar membrane, but showed characteristic differences. It appears that breaks in the internal limiting membrane always stimulate proliferation of preretinal glial membranes. Similar cellular morphology of the membranes associated with breaks is consistent with a common cell of origin. Limited proliferation of these membranes suggests that surface gliosis is normally inhibited when the cells contact either intact basement membrane or vitreous.

  14. Retinal glia promote dorsal root ganglion axon regeneration.

    Directory of Open Access Journals (Sweden)

    Barbara Lorber

    Full Text Available Axon regeneration in the adult central nervous system (CNS is limited by several factors including a lack of neurotrophic support. Recent studies have shown that glia from the adult rat CNS, specifically retinal astrocytes and Müller glia, can promote regeneration of retinal ganglion cell axons. In the present study we investigated whether retinal glia also exert a growth promoting effect outside the visual system. We found that retinal glial conditioned medium significantly enhanced neurite growth and branching of adult rat dorsal root ganglion neurons (DRG in culture. Furthermore, transplantation of retinal glia significantly enhanced regeneration of DRG axons past the dorsal root entry zone after root crush in adult rats. To identify the factors that mediate the growth promoting effects of retinal glia, mass spectrometric analysis of retinal glial conditioned medium was performed. Apolipoprotein E and secreted protein acidic and rich in cysteine (SPARC were found to be present in high abundance, a finding further confirmed by western blotting. Inhibition of Apolipoprotein E and SPARC significantly reduced the neuritogenic effects of retinal glial conditioned medium on DRG in culture, suggesting that Apolipoprotein E and SPARC are the major mediators of this regenerative response.

  15. Toward high-resolution optoelectronic retinal prosthesis

    Science.gov (United States)

    Palanker, Daniel; Huie, Philip; Vankov, Alexander; Asher, Alon; Baccus, Steven

    2005-04-01

    It has been already demonstrated that electrical stimulation of retina can produce visual percepts in blind patients suffering from macular degeneration and retinitis pigmentosa. Current retinal implants provide very low resolution (just a few electrodes), while several thousand pixels are required for functional restoration of sight. We present a design of the optoelectronic retinal prosthetic system that can activate a retinal stimulating array with pixel density up to 2,500 pix/mm2 (geometrically corresponding to a visual acuity of 20/80), and allows for natural eye scanning rather than scanning with a head-mounted camera. The system operates similarly to "virtual reality" imaging devices used in military and medical applications. An image from a video camera is projected by a goggle-mounted infrared LED-LCD display onto the retina, activating an array of powered photodiodes in the retinal implant. Such a system provides a broad field of vision by allowing for natural eye scanning. The goggles are transparent to visible light, thus allowing for simultaneous utilization of remaining natural vision along with prosthetic stimulation. Optical control of the implant allows for simple adjustment of image processing algorithms and for learning. A major prerequisite for high resolution stimulation is the proximity of neural cells to the stimulation sites. This can be achieved with sub-retinal implants constructed in a manner that directs migration of retinal cells to target areas. Two basic implant geometries are described: perforated membranes and protruding electrode arrays. Possibility of the tactile neural stimulation is also examined.

  16. Prevalence of comorbid retinal disease in patients with glaucoma at an academic medical center

    Directory of Open Access Journals (Sweden)

    Griffith JF

    2015-07-01

    Full Text Available Joseph F Griffith,1 Jeffrey L Goldberg2 1Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, 2Shiley Eye Center, University of California San Diego, La Jolla, CA, USA Background: Patients with various retinal diseases and patients who have undergone retinal procedures and surgeries have an increased risk of developing ocular hypertension and glaucoma. Little is known about the epidemiology of comorbid retinal diseases in glaucoma patients. This study evaluated the prevalence of retinal comorbidities in a population of patients with five types of glaucoma.Methods: A longitudinal, retrospective study was conducted using International Classification of Disease (ICD-9 billing records from 2003 to 2010 at an academic medical center. Patients were classified as having primary open-angle glaucoma (POAG, low tension open-angle glaucoma (NTG, pigmentary open-angle glaucoma, chronic-angle closure glaucoma (CACG, or pseudoexfoliation glaucoma (PXG if they had at least three clinic visits with the same ICD-9 code. Patients were classified as having a retinal comorbidity if they had two visits with the same code. Variables were analyzed with the independent t-test, χ2 test, analysis of variance, or Fisher’s exact test.Results: A total of 5,154 patients had glaucoma, and 14.8% of these had a retinal comorbidity. The prevalence of comorbid retinal disease was higher in patients with POAG (15.7% than in those with NTG (10.7%, PXG (10.1%, or pigmentary open-angle glaucoma (3.7%; P<0.05. Two hundred and two patients had diabetic retinopathy, with POAG patients (4.5% having a higher prevalence than those with CACG (1.4% or PXG (0.6%; P<0.001. There were 297 patients who had macular degeneration and both POAG (2.0% and PXG patients (2.9% had a higher prevalence of nonexudative macular degeneration than those with CACG (0%; P<0.01. Patients with comorbid retinal disease had a higher prevalence of blindness and low vision than those without comorbid

  17. Silver nano - a trove for retinal therapies.

    Science.gov (United States)

    Kalishwaralal, Kalimuthu; Barathmanikanth, Selvaraj; Pandian, Sureshbabu Ram Kumar; Deepak, Venkatraman; Gurunathan, Sangiliyandi

    2010-07-14

    Pathological retinal angiogenesis (neovascularization) is one of the most feared complications among retinal diseases, leading to visual impairment and irreversible blindness. Recent findings made by us on therapeutic applications of biologically synthesized silver nanoparticles (AgNPs) against VEGF induced retinal endothelial cells, elucidates the effectual inhibitory activities of AgNPs over the downstream signaling pathways (Src and AKT/PI3K) leading to retinal angiogenesis. The current review focuses on the imperative role of VEGF induced angiogenesis in the development of retinal neovascularization and despite the fact that several VEGF targeting ocular drugs are available; the review examines the need for a cost economic alternative, thereby suggesting the role of AgNPs as an emerging economic ocular drug for retinal therapies. The current technologies available for the development of targeted and controlled release of drugs is being discussed and a model has been proposed for the amenable targeting mechanism, by which Poly gamma glutamic acid (PGA) capsulated AgNPs conjugated to cyclic RGD peptides carry out a sustained controlled release specifically targeting the neovascularization cells and induce apoptosis unaffecting the normal retinal cells. These constructs consequently affirm the futuristic application of silver nanoparticles as a boon to ocular therapies. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  18. White centered retinal hemorrhages in vitamin b(12) deficiency anemia.

    Science.gov (United States)

    Zehetner, Claus; Bechrakis, Nikolaos E

    2011-05-01

    To report a case of severe vitamin B(12) deficiency anemia presenting with white centered retinal hemorrhages. Interventional case report. A 40-year-old man, general practitioner himself, presented with a 1-day history of diminished left visual acuity and a drop-shaped central scotoma. The corrected visual acuities were 20/20, OD and 20/100, OS. Ophthalmic examination revealed bilaterally pale tarsal conjunctiva, discretely icteric bulbar conjunctiva and disseminated white centered intraretinal hemorrhages with foveal involvement. OCT imaging through these lesions revealed a retinal thickening caused by a sub-ILM accumulation of hyperreflective and inhomogeneous deposits within the nerve fiber layer. Immediate laboratory work-up showed severe megaloblastic anemia caused by vitamin B(12) deficiency requiring erythrocyte transfusions. Most reports of white centered retinal hemorrhages have been described in patients with leukemic retinopathy and bacterial endocarditis. It is interesting that this case of vitamin B(12) deficiency anemia retinopathy has a clinically indistinguishable fundus appearance. This is probably due to the common pathology of capillary disruption and subsequent hemostatic fibrin plug formation. In megaloblastic anemia, direct anoxia results in endothelial dysfunction. The loss of impermeability allows extrusion of whole blood and subsequent diffusion from the disrupted site throughout and above the nerve fiber layer. Therefore the biomicroscopic pattern of white centered hemorrhages observed in anemic retinopathy is most likely due to the clot formation as the reparative sequence after capillary rupture.

  19. White Centered Retinal Hemorrhages in Vitamin B12 Deficiency Anemia

    Directory of Open Access Journals (Sweden)

    Claus Zehetner

    2011-05-01

    Full Text Available Background: To report a case of severe vitamin B12 deficiency anemia presenting with white centered retinal hemorrhages. Methods: Interventional case report. Results: A 40-year-old man, general practitioner himself, presented with a 1-day history of diminished left visual acuity and a drop-shaped central scotoma. The corrected visual acuities were 20/20, OD and 20/100, OS. Ophthalmic examination revealed bilaterally pale tarsal conjunctiva, discretely icteric bulbar conjunctiva and disseminated white centered intraretinal hemorrhages with foveal involvement. OCT imaging through these lesions revealed a retinal thickening caused by a sub-ILM accumulation of hyperreflective and inhomogeneous deposits within the nerve fiber layer. Immediate laboratory work-up showed severe megaloblastic anemia caused by vitamin B12 deficiency requiring erythrocyte transfusions. Discussion: Most reports of white centered retinal hemorrhages have been described in patients with leukemic retinopathy and bacterial endocarditis. It is interesting that this case of vitamin B12 deficiency anemia retinopathy has a clinically indistinguishable fundus appearance. This is probably due to the common pathology of capillary disruption and subsequent hemostatic fibrin plug formation. In megaloblastic anemia, direct anoxia results in endothelial dysfunction. The loss of impermeability allows extrusion of whole blood and subsequent diffusion from the disrupted site throughout and above the nerve fiber layer. Therefore the biomicroscopic pattern of white centered hemorrhages observed in anemic retinopathy is most likely due to the clot formation as the reparative sequence after capillary rupture.

  20. The Role of Gene Therapy in the Treatment of Retinal Diseases: A Review.

    Science.gov (United States)

    Campa, C; Gallenga, C E; Bolletta, E; Perri, P

    2017-01-01

    Gene therapy represents the therapeutic delivery of nucleic acid polymers into patient cells with the aim of treating an underlying disease. Over the past 2 decades this new therapy has made substantial progress owing to better understanding of the pathobiologic basis of various diseases coupled with growth of gene transfer biotechnologies. The eye, in particular, represents a suitable target for such therapy due to the immune privilege provided by the blood-ocular barrier, the ability to directly visualize, access and locally treat the cells and the minimal amount of vector needed given the size of this organ. It is not surprising therefore that several clinical trials are now ongoing in this field. The purpose of this review was to provide an update on gene therapy for retinal diseases, discussing differences in treatment strategies, vector designs and surgical techniques. Research was performed on PubMed, ClinicalTrials.gov, and Home Genetic Reference. We additionally utilized the internet database for genetics of retinal diseases, the portal for rare diseases and orphan drugs and the NCBI database Online Mendelian Inheritance in Man. No restriction was applied on the language of publications. We present the available results of current active clinical trials for inherited retinal disease such as Leber's congenital amaurosis type 2, choroideremia, Stargardt disease, achromatopsia and juvenile X-linked retinoschisis. We also illustrate a new approach of this therapy for the treatment of much more common ocular diseases such as age-related macular degeneration and diabetic retinopathy. Gene therapy represents an emerging and promising therapeutic approach for the treatment not only of rare inherited retinal diseases but also much more common retinal pathologies. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. A novel method for retinal optic disc detection using bat meta-heuristic algorithm.

    Science.gov (United States)

    Abdullah, Ahmad S; Özok, Yasa Ekşioğlu; Rahebi, Javad

    2018-05-09

    Normally, the optic disc detection of retinal images is useful during the treatment of glaucoma and diabetic retinopathy. In this paper, the novel preprocessing of a retinal image with a bat algorithm (BA) optimization is proposed to detect the optic disc of the retinal image. As the optic disk is a bright area and the vessels that emerge from it are dark, these facts lead to the selected segments being regions with a great diversity of intensity, which does not usually happen in pathological regions. First, in the preprocessing stage, the image is fully converted into a gray image using a gray scale conversion, and then morphological operations are implemented in order to remove dark elements such as blood vessels, from the images. In the next stage, a bat algorithm (BA) is used to find the optimum threshold value for the optic disc location. In order to improve the accuracy and to obtain the best result for the segmented optic disc, the ellipse fitting approach was used in the last stage to enhance and smooth the segmented optic disc boundary region. The ellipse fitting is carried out using the least square distance approach. The efficiency of the proposed method was tested on six publicly available datasets, MESSIDOR, DRIVE, DIARETDB1, DIARETDB0, STARE, and DRIONS-DB. The optic disc segmentation average overlaps and accuracy was in the range of 78.5-88.2% and 96.6-99.91% in these six databases. The optic disk of the retinal images was segmented in less than 2.1 s per image. The use of the proposed method improved the optic disc segmentation results for healthy and pathological retinal images in a low computation time. Graphical abstract ᅟ.

  2. A Method for Combined Retinal Vascular and Tissue Oxygen Tension Imaging.

    Science.gov (United States)

    Felder, Anthony E; Wanek, Justin; Tan, Michael R; Blair, Norman P; Shahidi, Mahnaz

    2017-09-06

    The retina requires adequate oxygenation to maintain cellular metabolism and visual function. Inner retinal oxygen metabolism is directly related to retinal vascular oxygen tension (PO 2 ) and inner retinal oxygen extraction fraction (OEF), whereas outer retinal oxygen consumption (QO 2 ) relies on oxygen availability by the choroid and is contingent upon retinal tissue oxygen tension (tPO 2 ) gradients across the retinal depth. Thus far, these oxygenation and metabolic parameters have been measured independently by different techniques in separate animals, precluding a comprehensive and correlative assessment of retinal oxygenation and metabolism dynamics. The purpose of the current study is to report an innovative optical system for dual oxyphor phosphorescence lifetime imaging to near-simultaneously measure retinal vascular PO 2 and tPO 2 in rats. The use of a new oxyphor with different spectral characteristics allowed differentiation of phosphorescence signals from the retinal vasculature and tissue. Concurrent measurements of retinal arterial and venous PO 2 , tPO 2 through the retinal depth, inner retinal OEF, and outer retinal QO 2 were demonstrated, permitting a correlative assessment of retinal oxygenation and metabolism. Future application of this method can be used to investigate the relations among retinal oxygen content, extraction and metabolism under pathologic conditions and thus advance knowledge of retinal hypoxia pathophysiology.

  3. Retinal layer measurements after successful macula-off retinal detachment repair using optical coherence tomography.

    Science.gov (United States)

    Menke, Marcel N; Kowal, Jens H; Dufour, Pascal; Wolf-Schnurrbusch, Ute E; Ceklic, Lala; Framme, Carsten; Wolf, Sebastian

    2014-09-04

    Optical coherence tomography (OCT) was used to analyze the thickness of various retinal layers of patients following successful macula-off retinal detachment (RD) repair. Optical coherence tomography scans of patients after successful macula-off RD repair were reanalyzed with a subsegmentation algorithm to measure various retinal layers. Regression analysis was performed to correlate time after surgery with changes in layer thickness. In addition, patients were divided in two groups. Group 1 had a follow-up period after surgery of up to 7 weeks (range, 21-49 days). In group 2, the follow-up period was >8 weeks (range, 60-438 days). Findings were compared to a group of age-matched healthy controls. Correlation analysis showed a significant positive correlation between inner nuclear-outer plexiform layer (INL-OPL) thickness and time after surgery (P=0.0212; r2=0.1551). Similar results were found for the ellipsoid zone-retinal pigment epithelium complex (EZ-RPE) thickness (P=0.005; r2=0.2215). Ganglion cell-inner plexiform layer thickness (GCL-IPL) was negatively correlated with time after surgery (P=0.0064; r2=0.2101). For group comparison, the retinal nerve fiber layer in both groups was thicker compared to controls. The GCL-IPL showed significant thinning in group 2. The outer nuclear layer was significantly thinner in groups 1 and 2 compared to controls. The EZ-RPE complex was significantly thinner in groups 1 and 2 compared to controls. In addition, values in group 1 were significantly thinner than in group 2. Optical coherence tomography retinal layer thickness measurements after successful macular-off RD repair revealed time-dependent thickness changes. Inner nuclear-outer plexiform layer thickness and EZ-RPE thickness was positively correlated with time after surgery. Ganglion cell-inner plexiform layer thickness was negatively correlated with time after surgery. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  4. Gene Correction Reverses Ciliopathy and Photoreceptor Loss in iPSC-Derived Retinal Organoids from Retinitis Pigmentosa Patients

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    Wen-Li Deng

    2018-04-01

    Full Text Available Summary: Retinitis pigmentosa (RP is an irreversible, inherited retinopathy in which early-onset nyctalopia is observed. Despite the genetic heterogeneity of RP, RPGR mutations are the most common causes of this disease. Here, we generated induced pluripotent stem cells (iPSCs from three RP patients with different frameshift mutations in the RPGR gene, which were then differentiated into retinal pigment epithelium (RPE cells and well-structured retinal organoids possessing electrophysiological properties. We observed significant defects in photoreceptor in terms of morphology, localization, transcriptional profiling, and electrophysiological activity. Furthermore, shorted cilium was found in patient iPSCs, RPE cells, and three-dimensional retinal organoids. CRISPR-Cas9-mediated correction of RPGR mutation rescued photoreceptor structure and electrophysiological property, reversed the observed ciliopathy, and restored gene expression to a level in accordance with that in the control using transcriptome-based analysis. This study recapitulated the pathogenesis of RPGR using patient-specific organoids and achieved targeted gene therapy of RPGR mutations in a dish as proof-of-concept evidence. : Jin and colleagues demonstrate that patient-specific iPSC-derived 3D retinae can recapitulate disease progress of retinitis pigmentosa through presenting defects in photoreceptor morphology, gene profile, and electrophysiology, as well as the defective ciliogenesis in iPSCs, iPSC-RPE, and 3D retinae. CRISPR/Cas9-mediated gene correction can rescue not only photoreceptor structure and electrophysiological property but also observed ciliopathy. Keywords: RPGR, photoreceptor, electrophysiology, retinitis pigmentosa, patient-derived iPSCs, retinal organoid, RPE cells, cilium, ciliopathy, disease modeling

  5. A clinical approach to the diagnosis of retinal vasculitis.

    Science.gov (United States)

    El-Asrar, Ahmed M Abu; Herbort, Carl P; Tabbara, Khalid F

    2010-04-01

    Retinal vasculitis is a sight-threatening inflammatory eye condition that involves the retinal vessels. Detection of retinal vasculitis is made clinically, and is confirmed with the help of fundus fluorescein angiography. Active vascular disease is characterized by exudates around retinal vessels resulting in white sheathing or cuffing of the affected vessels. In this review, a practical approach to the diagnosis of retinal vasculitis is discussed based on ophthalmoscopic and fundus fluorescein angiographic findings.

  6. MR detection of retinal hemorrhages: correlation with graded ophthalmologic exam

    International Nuclear Information System (INIS)

    Beavers, Angela J.; Allbery, Sandra M.; Stagner, Anna M.; Hejkal, Thomas W.; Lyden, Elizabeth R.; Haney, Suzanne B.

    2015-01-01

    Dilated fundoscopic exam is considered the gold standard for detecting retinal hemorrhage, but expertise in obtaining this exam is not always immediately available. MRI can detect retinal hemorrhages, but correlation of the grade or severity of retinal hemorrhage on dilated fundoscopic exam with retinal hemorrhage visibility on MRI has not been described. To determine the value of standard brain protocol MRI in detecting retinal hemorrhage and to determine whether there is any correlation with MR detection of retinal hemorrhage and the dilated fundoscopic exam grade of hemorrhage. We conducted a retrospective chart review of 77 children <2 years old who were seen for head trauma from April 2007 to July 2013 and had both brain MRI and dilated fundoscopic exam or retinal camera images. A staff pediatric radiologist and radiology resident reviewed the MR images. Retinal hemorrhages were graded by a chief ophthalmology resident on a 12-point scale based on the retinal hemorrhage type, size, location and extent as seen on review of retinal camera images and detailed reports by ophthalmologists. Higher scores indicated increased severity of retinal hemorrhages. There was a statistically significant difference in the median grade of retinal hemorrhage examination between children who had retinal hemorrhage detected on MRI and children who did not have retinal hemorrhage detected on MRI (P = 0.02). When examination grade was categorized as low-grade (1-4), moderate-grade (5-8) or high-grade (>8) hemorrhage, there was a statistically significant association between exam grade and diagnosis based on MRI (P = 0.008). For example, only 14% of children with low-grade retinal hemorrhages were identified on MRI compared to 76% of children with high-grade hemorrhages. MR detection of retinal hemorrhage demonstrated a sensitivity of 61%, specificity of 100%, positive predictive value of 100% and negative predictive value of 63%. Retinal hemorrhage was best seen on the gradient

  7. Relationship between target organ damage and blood pressure, retinal vessel calibre, oxidative stress and polymorphisms in VAV-2 and VAV-3 genes in patients with hypertension: a case–control study protocol (LOD-Hipertensión)

    Science.gov (United States)

    Gomez-Marcos, Manuel A; Gonzalez-Sarmiento, Rogelio; Recio-Rodríguez, José I; Agudo-Conde, Cristina; Gamella-Pozuelo, Luis; Perretta-Tejedor, Nuria; Martínez-Salgado, Carlos; García-Ortiz, Luis

    2014-01-01

    Introduction Target organ damage (TOD) is associated with increased cardiovascular risk. The study objectives were to analyse the relationship of TOD to blood pressure, size of retinal arteries and veins, oxidative stress and different polymorphisms in the VAV-2 and VAV-3 genes in participants with hypertension. Methods and analysis A case–control study to analyse the relationship between clinical, biochemical and genetic parameters and presence of cardiac, vascular and renal TOD in 486 patients with hypertension. Participants with TOD will be considered as cases, and those without TOD will be enrolled as controls. This will be a collaborative study conducted by the groups of Primary Care, Cardiovascular and Metabolic and Degenerative Diseases of the Instituto de Investigación Biomédica of Salamanca (IBSAL). Assessment of cardiac, renal and vascular TOD. Measurement of peripheral and central blood pressure, size of eye fundus arteries and veins, and oxidative stress, and polymorphisms in the VAV-2 and VAV-3 genes. Ethics and dissemination The study will be conducted after approval is obtained from the Ethics Committee of Hospital Clínico Universitario of Salamanca. All study participants will sign an informed consent to agree to participate in the study, and another consent to agree on the genetic study, in compliance with the Declaration of Helsinki and the WHO standards for observational studies. The results of this study will allow for an understanding of the relationship of the different TODs with blood pressure, retinal artery and vein diameters, oxidative stress and polymorphisms in VAV-2 and VAV-3 genes. Trial registration number Clinical Trials. gov Identifier: NCT02022618. PMID:24699462

  8. Free Amino Acids in the Blood Plasma of Pigs during Total Starvation

    Energy Technology Data Exchange (ETDEWEB)

    Cuperlovic, M.; Jovanovic, M.; Stosic, D. [Institute for the Application of Nuclear Energy in Agriculture, Veterinary Medicine and Forestry, Belgrade, Yugoslavia (Serbia)

    1968-07-01

    From the nutritional point of view it is interesting to establish whether the level of free amino acids in the blood plasma can be used as an indicator of protein anabolism and catabolism. Investigations to date have given no answer to this question. It is known that numerous exogenous and endogenous factors affect protein metabolism. These effects also vary with the level of protein intake and make the relationship between the quantitative and qualitative composition of the free amino acids pool and the total protein metabolism even more complicated. To reduce some of these factors, these investigations were done under the conditions of complete exclusion of exogenous nutrition. Piglets, aged 8-10 weeks, were subjected to total starvation in the course of 28 d. During this period, the body weight, serum protein content, plasma amino acid concentration and plasma urea concentration were followed. During the whole experimental period the body weight decreased, rapidly at the beginning and more slowly towards the end. The mean total body weight loss was 44.6 % of the first day's weight. The serum protein content increased slightly at the beginning of starvation and then, towards the end of the experiment, decreased, reaching a value that was only a little lower than the protein content determined before the onset of starvation. Changes of the quantitative composition.of the free amino acid pool did not follow the changes of the serum protein content. At the beginning of starvation, concentrations of a great number of amino acids increased in accordance with some earlier results. After long periods of starvation, however, differences between individual amino acids become more clear. Concentrations of some amino acids, e.g. lysine, increased continually during the whole period, while concentrations of most of the other amino acids remained for some time at high levels and only in the last week of starvation decreased to the values similar to those observed at the

  9. Combined Intra-Articular and Intravenous Tranexamic Acid Reduces Blood Loss in Total Knee Arthroplasty

    DEFF Research Database (Denmark)

    Nielsen, Christian Skovgaard; Jans, Øivind; Ørsnes, Thue

    2016-01-01

    BACKGROUND: In total knee arthroplasty, both intravenous (IV) and intra-articular (IA) administration of tranexamic acid (TXA) have been shown to reduce blood loss in several randomized controlled trials, although routine use of systemic TXA is considerably more common. However, to our knowledge...

  10. A robust technique based on VLM and Frangi filter for retinal vessel extraction and denoising.

    Directory of Open Access Journals (Sweden)

    Khan Bahadar Khan

    Full Text Available The exploration of retinal vessel structure is colossally important on account of numerous diseases including stroke, Diabetic Retinopathy (DR and coronary heart diseases, which can damage the retinal vessel structure. The retinal vascular network is very hard to be extracted due to its spreading and diminishing geometry and contrast variation in an image. The proposed technique consists of unique parallel processes for denoising and extraction of blood vessels in retinal images. In the preprocessing section, an adaptive histogram equalization enhances dissimilarity between the vessels and the background and morphological top-hat filters are employed to eliminate macula and optic disc, etc. To remove local noise, the difference of images is computed from the top-hat filtered image and the high-boost filtered image. Frangi filter is applied at multi scale for the enhancement of vessels possessing diverse widths. Segmentation is performed by using improved Otsu thresholding on the high-boost filtered image and Frangi's enhanced image, separately. In the postprocessing steps, a Vessel Location Map (VLM is extracted by using raster to vector transformation. Postprocessing steps are employed in a novel way to reject misclassified vessel pixels. The final segmented image is obtained by using pixel-by-pixel AND operation between VLM and Frangi output image. The method has been rigorously analyzed on the STARE, DRIVE and HRF datasets.

  11. Retinal astrocytoma in a dog.

    Science.gov (United States)

    Kuroki, Keiichi; Kice, Nathan; Ota-Kuroki, Juri

    2017-09-01

    A miniature schnauzer dog presenting with hyphema and glaucoma of the right eye had a retinal neoplasm. Neoplastic cells stained positively for glial fibrillary acidic protein, vimentin, and S-100 and largely negatively for oligodendrocyte transcription factor 2 by immunohistochemistry. The clinical and histopathological features of canine retinal astrocytomas are discussed.

  12. Retinal oxygen saturation before and after glaucoma surgery.

    Science.gov (United States)

    Nitta, Eri; Hirooka, Kazuyuki; Shimazaki, Takeru; Sato, Shino; Ukegawa, Kaori; Nakano, Yuki; Tsujikawa, Akitaka

    2017-08-01

    This study compared retinal vessel oxygen saturation before and after glaucoma surgery. Retinal oxygen saturation in glaucoma patients was measured using a non-invasive spectrophotometric retinal oximeter. Adequate image quality was found in 49 of the 108 consecutive glaucoma patients recruited, with 30 undergoing trabeculectomy, 11 EX-PRESS and eight trabeculotomy. Retinal oxygen saturation measurements in the retinal arterioles and venules were performed at 1 day prior to and at approximately 10 days after surgery. Statistical analysis was performed using a Student's t-test. After glaucoma surgery, intraocular pressure (IOP) decreased from 19.8 ± 7.7 mmHg to 9.0 ± 5.7 mmHg (p glaucoma surgery had an effect on the retinal venous oxygen saturation. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  13. Risk of Retinal Detachment After Pediatric Cataract Surgery

    DEFF Research Database (Denmark)

    Haargaard, Birgitte; Andersen, Elisabeth W; Oudin, Anna

    2014-01-01

    PURPOSE: To determine the long-term risk of retinal detachment following pediatric cataract surgery and to identify risk factors for retinal detachment. METHODS: We included all children (aged 0 to 17 years) who during the time period of 1977 to 2005 underwent pediatric cataract surgery in Denmark...... was based on medical chart review. RESULTS: Among 1043 eyes of 656 children undergoing surgery for pediatric cataract, 25 eyes (23 children) developed retinal detachment at a median time of 9.1 years after surgery. The overall 20-year risk of retinal detachment was 7% (95% confidence interval [CI]: 3...... (16% [95% CI: 6%-24%]). CONCLUSIONS: The estimated overall risk of retinal detachment 20 years after pediatric cataract surgery was 7%, but only 3% for isolated cataract. Particularly high risks of retinal detachment after cataract surgery were associated with mental retardation and having other...

  14. Gene therapy for inherited retinal and optic nerve degenerations.

    Science.gov (United States)

    Moore, Nicholas A; Morral, Nuria; Ciulla, Thomas A; Bracha, Peter

    2018-01-01

    The eye is a target for investigational gene therapy due to the monogenic nature of many inherited retinal and optic nerve degenerations (IRD), its accessibility, tight blood-ocular barrier, the ability to non-invasively monitor for functional and anatomic outcomes, as well as its relative immune privileged state.Vectors currently used in IRD clinical trials include adeno-associated virus (AAV), small single-stranded DNA viruses, and lentivirus, RNA viruses of the retrovirus family. Both can transduce non-dividing cells, but AAV are non-integrating, while lentivirus integrate into the host cell genome, and have a larger transgene capacity. Areas covered: This review covers Leber's congenital amaurosis, choroideremia, retinitis pigmentosa, Usher syndrome, Stargardt disease, Leber's hereditary optic neuropathy, Achromatopsia, and X-linked retinoschisis. Expert opinion: Despite great potential, gene therapy for IRD raises many questions, including the potential for less invasive intravitreal versus subretinal delivery, efficacy, safety, and longevity of response, as well as acceptance of novel study endpoints by regulatory bodies, patients, clinicians, and payers. Also, ultimate adoption of gene therapy for IRD will require widespread genetic screening to identify and diagnose patients based on genotype instead of phenotype.

  15. [To cognize retinitis pigmentosa with scientific view].

    Science.gov (United States)

    Li, Gen-lin

    2009-03-01

    Retinitis pigmentosa (RP) is the most common inherited eye disease that usually leads into blind, and is high simplex and clinical heterogeneity. Recent years, some new hereditary forms have been found, such as digenic RP, mitochondrial RP, incomplete dominant inheritance RP. The phenotype of RP is multiplicity. Incompatible phenomenon between genotype and phenotypes was shown in some genes such as peripherin/RDS, RHO, RP2 and RP3. The complicated phenotype was shown in the rare RP forms, such as centricity RP, stemma RP, retinitis pigmentosa sine pigmento, and retinal degeneration slow. Retinal transplantation, retinal implantation, drug and neurotrophic factor therapy, and gene therapy have been well studied worldwide and presented some hopeful efficacy. Ophthalmologists and practitioners should cognize the new advance and new knowledge on RP therapy with a scientific view for better serving the RP patients.

  16. The relationship between total arterial revascularization and blood transfusion following coronary artery bypass grafting.

    Science.gov (United States)

    Djordjevic, Jasmina; Ngaage, Dumbor L

    2015-05-01

    Blood transfusion adversely affects the outcome of coronary artery bypass grafting (CABG), yet blood transfusion after CABG is still common. Total arterial revascularisation (TAR) is increasingly used in current practice but its impact on postoperative blood transfusion is not known. We reviewed the cardiothoracic and blood bank databases and collected data for isolated primary CABG patients from July 2007 to June 2012, excluding patients who had a single graft (n = 148). Perioperative variables of TAR patients (n = 745) were compared with patients who had one or more venous grafts (SVG, n = 1,761) for first-time isolated CABG. The conduits used in TAR patients were predominantly left internal thoracic and radial arteries. Matched group comparison of TAR and SVG patients was performed. The association of TAR with blood transfusion was investigated using multivariate and matched analysis. Of 2,506 patients, the 745 (29.7 %) that had TAR were generally younger, with less complex coronary artery disease and less often diabetic. After correcting for these by 1:1 matching, the mean chest tube drainage and rates of blood transfusion remained significantly lower (p transfused in TAR patients. By multivariate analysis, TAR had an independent effect on reducing blood transfusion after CABG [odds ratio (OR) 0.67, 95 % confidence interval (CI) 0.47-0.97, p = .03]. TAR achieved predominantly with left internal thoracic and radial arteries substantially reduced blood transfusion rates after primary CABG. Further studies are warranted.

  17. Retinitis pigmentosa, pigmentary retinopathies, and neurologic diseases.

    Science.gov (United States)

    Bhatti, M Tariq

    2006-09-01

    Retinitis pigmentosa (RP) refers to a group of inherited retinal diseases with phenotypic and genetic heterogeneity. The pathophysiologic basis of the progressive visual loss in patients with RP is not completely understood but is felt to be due to a primary retinal photoreceptor cell degenerative process mainly affecting the rods of the peripheral retina. In most cases RP is seen in isolation (nonsyndromic), but in some other cases it may be a part of a genetic, metabolic, or neurologic syndrome or disorder. Nyctalopia, or night blindness, is the most common symptom of RP. The classic fundus appearance of RP includes retinal pigment epithelial cell changes resulting in retinal hypo- or hyperpigmentation ("salt-and-pepper"), retinal granularity, and bone spicule formation. The retinal vessels are often narrowed or attenuated and there is a waxy pallor appearance of the optic nerve head. Electroretinography will demonstrate rod and cone photoreceptor cell dysfunction and is a helpful test in the diagnosis and monitoring of patients with RP. A detailed history with pedigree analysis, a complete ocular examination, and the appropriate paraclinical testing should be performed in patients complaining of visual difficulties at night or in dim light. This review discusses the clinical manifestations of RP as well as describing the various systemic diseases, with a special emphasis on neurologic diseases, associated with a pigmentary retinopathy.

  18. A new topical hemostatic agent TT-173 reduces blood loss in a sheep model of total knee arthroplasty.

    Science.gov (United States)

    Centeno, Alberto; Rojas, Santiago; Arias, Belén; Miquel, Ignasi; Sánchez, Pilar; Ureta, Claudia; Rincón, Esther; López, Ramón; Murat, Jesús

    2017-12-01

    Total knee arthroplasty is associated with blood loss during the intervention and may require allogenic blood transfusion. Treatments such as tranexamic acid and fibrin sealants improved the bleeding control in several clinical trials, but the hemorrhage associated with the intervention is still significant. Thus far, very few studies have evaluated hemostatic treatments in animal models of total knee arthroplasty. This work describes a sheep model of bleeding associated with total knee arthroplasty and investigates a new class of hemostatic treatment based on recombinant tissue factor. Sheep were treated with the anticoagulant heparin, and the joint was accessed by a paramedial incision. Ligaments and menisci were eliminated and femoral condyles and tibia plateau were sectioned exposing the trabecular bone. An intra-articular drain was used to recover and quantify the blood loss during the 90-min period after treatment. The efficacy of one milligram and three milligrams of TT-173 was evaluated and compared with tranexamic acid. The occurrence of analytical alterations and systemic absorption was also investigated. Treatment with TT-173 reduced the blood loss in comparison with control or tranexamic acid. No significant differences were observed between the two doses evaluated. Moreover, a dose of six milligrams of TT-173 did not induce any clinical or analytical alteration, and significant systemic absorption was not observed. Data obtained strongly suggest that TT-173 could be useful in reducing the blood loss associated with total knee arthroplasty and without safety concerns derived from the systemic absorption of the product. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Cytomegalovirus retinitis

    Science.gov (United States)

    ... have weakened immune systems as a result of: HIV/AIDS Bone marrow transplant Chemotherapy Drugs that suppress the immune system Organ transplant Symptoms Some people with CMV retinitis have no symptoms. ...

  20. Retinal vascular and structural dynamics during acute hyperglycaemia

    DEFF Research Database (Denmark)

    Klefter, Oliver N; Lauritsen, Tina Vilsbøll; Knop, Filip K

    2015-01-01

    PURPOSE: To compare retinal vascular dynamics during acute hyperglycaemia in patients with type 2 diabetes and healthy volunteers. METHODS: Twenty-one patients with type 2 diabetes and 27 healthy controls were examined with fundus photographic measurement of retinal vessel diameters, retinal...

  1. Relationship of retinal morphology and retinal sensitivity in the treatment of neovascular age-related macular degeneration using aflibercept.

    Science.gov (United States)

    Sulzbacher, Florian; Roberts, Philipp; Munk, Marion R; Kaider, Alexandra; Kroh, Maria Elisabeth; Sacu, Stefan; Schmidt-Erfurth, Ursula

    2014-12-11

    To relate the functional response to distinct morphological features of the retina during aflibercept treatment for neovascular AMD (nAMD). A total of 726 retinal locations in 22 consecutive eyes presenting with treatment-naive nAMD underwent a standardized examination with spectral-domain optical coherence tomography (SD-OCT) and topographic microperimetry (MP) at baseline, after 3 and 12 months of continuous intravitreal aflibercept therapy. The retinal sensitivity at each stimulus location was registered to the corresponding location on SD-OCT morphology. Subsequently, the microperimetric responses were evaluated with respect to the following underlying SD-OCT features: neovascular complex (NVC), subretinal fluid (SRF), intraretinal fluid (IRF), intraretinal cystoid space (IRC), serous pigment epithelium detachment (sPED), and fibrovascular pigment epithelium detachment (fPED). Baseline sensitivity was reduced to mean values of 1.8 dB in NVC, 2.2 dB in IRC, 2.8 dB in IRF, 2.6 dB in sPED, 3.6 dB in SRF, and 4.6 dB in fPED. Improvements in retinal sensitivity were most pronounced during the initial 3-month interval, when significant recovery was documented for SRF and sPED with +4.0/5.5 dB (P 0.05 for each category). Significant functional benefits following intravitreal aflibercept treatment could be detected over all defined morphological pathologies. The level of improvement varied dependent on the associated feature with the best prognosis for visual improvement in SRF and sPED and least with intraretinal fluid and particularly intraretinal cysts. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  2. Study of retinal neurodegeneration and maculopathy in diabetic Meriones shawi: A particular animal model with human-like macula.

    Science.gov (United States)

    Hammoum, Imane; Benlarbi, Maha; Dellaa, Ahmed; Szabó, Klaudia; Dékány, Bulcsú; Csaba, Dávid; Almási, Zsuzsanna; Hajdú, Rozina I; Azaiz, Rached; Charfeddine, Ridha; Lukáts, Ákos; Ben Chaouacha-Chekir, Rafika

    2017-09-01

    The purpose of this work was to evaluate a potentially useful animal model, Meriones shawi (M.sh)-developing metabolic X syndrome, diabetes and possessing a visual streak similar to human macula-in the study of diabetic retinopathy and diabetic macular edema (DME). Type 2 diabetes (T2D) was induced by high fat diet administration in M.sh. Body weights, blood glucose levels were monitored throughout the study. Diabetic retinal histopathology was evaluated 3 and 7 months after diabetes induction. Retinal thickness was measured, retinal cell types were labeled by immunohistochemistry and the number of stained elements were quantified. Apoptosis was determined with TUNEL assay. T2D induced progressive changes in retinal histology. A significant decrease of retinal thickness and glial reactivity was observed without an increase in apoptosis rate. Photoreceptor outer segment degeneration was evident, with a significant decrease in the number of all cones and M-cone subtype, but-surprisingly-an increase in S-cones. Damage of the pigment epithelium was also confirmed. A decrease in the number and labeling intensity of parvalbumin- and calretinin-positive amacrine cells and a loss of ganglion cells was detected. Other cell types showed no evident alterations. No DME-like condition was noticed even after 7 months. M.sh could be a useful model to study the evolution of diabetic retinal pathology and to identify the role of hypertension and dyslipidemia in the development of the reported alterations. Longer follow up would be needed to evaluate the potential use of the visual streak in modeling human macular diseases. © 2017 Wiley Periodicals, Inc.

  3. Basis and Design of a Randomized Clinical Trial to Evaluate the Effect of Levosulpiride on Retinal Alterations in Patients With Diabetic Retinopathy and Diabetic Macular Edema.

    Science.gov (United States)

    Robles-Osorio, Ma Ludivina; García-Franco, Renata; Núñez-Amaro, Carlos D; Mira-Lorenzo, Ximena; Ramírez-Neria, Paulina; Hernández, Wendy; López-Star, Ellery; Bertsch, Thomas; Martínez de la Escalera, Gonzalo; Triebel, Jakob; Clapp, Carmen

    2018-01-01

    Diabetic retinopathy (DR) and diabetic macular edema (DME) are potentially blinding, microvascular retinal diseases in people with diabetes mellitus. Preclinical studies support a protective role of the hormone prolactin (PRL) due to its ocular incorporation and conversion to vasoinhibins, a family of PRL fragments that inhibit ischemia-induced retinal angiogenesis and diabetes-derived retinal vasopermeability. Here, we describe the protocol of an ongoing clinical trial investigating a new therapy for DR and DME based on elevating the circulating levels of PRL with the prokinetic, dopamine D2 receptor blocker, levosulpiride. It is a prospective, randomized, double-blind, placebo-controlled trial enrolling male and female patients with type 2 diabetes having DME, non-proliferative DR (NPDR), proliferative DR (PDR) requiring vitrectomy, and DME plus standard intravitreal therapy with the antiangiogenic agent, ranibizumab. Patients are randomized to receive placebo (lactose pill, orally TID) or levosulpiride (75 mg/day orally TID) for 8 weeks (DME and NPDR), 1 week (the period before vitrectomy in PDR), or 12 weeks (DME plus ranibizumab). In all cases the study medication is taken on top of standard therapy for diabetes, blood pressure control, or other medical conditions. Primary endpoints in groups 1 and 2 (DME: placebo and levosulpiride), groups 3 and 4 (NPDR: placebo and levosulpiride), and groups 7 and 8 (DME plus ranibizumab: placebo and levosulpiride) are changes from baseline in visual acuity, retinal thickness assessed by optical coherence tomography, and retinal microvascular abnormalities evaluated by fundus biomicroscopy and fluorescein angiography. Changes in serum PRL levels and of PRL and vasoinhibins levels in the vitreous between groups 5 and 6 (PDR undergoing vitrectomy: placebo and levosulpiride) serve as proof of principle that PRL enters the eye to counteract disease progression. Secondary endpoints are changes during the follow-up of health

  4. Blood Transfusion During Total Ankle Arthroplasty Is Associated With Increased In-Hospital Complications and Costs.

    Science.gov (United States)

    Ewing, Michael A; Huntley, Samuel R; Baker, Dustin K; Smith, Kenneth S; Hudson, Parke W; McGwin, Gerald; Ponce, Brent A; Johnson, Michael D

    2018-04-01

    Total ankle arthroplasty (TAA) is an increasingly used, effective treatment for end-stage ankle arthritis. Although numerous studies have associated blood transfusion with complications following hip and knee arthroplasty, its effects following TAA are largely unknown. This study uses data from a large, nationally representative database to estimate the association between blood transfusion and inpatient complications and hospital costs following TAA. Using the Nationwide Inpatient Sample (NIS) database from 2004 to 2014, 25 412 patients who underwent TAA were identified, with 286 (1.1%) receiving a blood transfusion. Univariate analysis assessed patient and hospital factors associated with blood transfusion following TAA. Patients requiring blood transfusion were more likely to be female, African American, Medicare recipients, and treated in nonteaching hospitals. Average length of stay for patients following transfusion was 3.0 days longer, while average inpatient cost was increased by approximately 50%. Patients who received blood transfusion were significantly more likely to suffer from congestive heart failure, peripheral vascular disease, hypothyroidism, coagulation disorder, or anemia. Acute renal failure was significantly more common among patients receiving blood transfusion ( P < .001). Blood transfusions following TAA are infrequent and are associated with multiple medical comorbidities, increased complications, longer hospital stays, and increased overall cost. Level III: Retrospective, comparative study.

  5. Retinal complications of gout: a case report and review of the literature.

    Science.gov (United States)

    Jiang, Ying; Brenner, Jason E; Foster, William J

    2018-01-19

    There have been few reported findings of posterior segment complications of gout. While exudative lesions, an increased risk of macular degeneration, and vascular occlusions have been previously reported, to our knowledge, refractile macular lesions have not been reported in a patient with chronic uncontrolled gout. Highly refractile, crystal-like lesions were found in the macula of a 62 year old male patient with chronically uncontrolled gout. The lesions appeared at the termination of retinal arterioles and were located at the level of the retinal pigment epithelium. The lesions did not stain with fluorescein and were associated with larger areas geographic atrophy. Review of the patient's blood tests revealed well-controlled vasculopathic risk factors. Fundus appearance and best-corrected visual acuity remained stable over 12 months of follow-up during which the uric acid levels were well controlled. Retinopathy may be associated with chronically uncontrolled gout and patients with visual complaints should undergo a dilated examination in addition to the typical anterior segment slit-lamp exam.

  6. Retinal pigment epithelium culture;a potential source of retinal stem cells.

    Science.gov (United States)

    Akrami, Hassan; Soheili, Zahra-Soheila; Khalooghi, Keynoush; Ahmadieh, Hamid; Rezaie-Kanavi, Mojgan; Samiei, Shahram; Davari, Malihe; Ghaderi, Shima; Sanie-Jahromi, Fatemeh

    2009-07-01

    To establish human retinal pigment epithelial (RPE) cell culture as a source for cell replacement therapy in ocular diseases. Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered.

  7. Progress toward the maintenance and repair of degenerating retinal circuitry.

    Science.gov (United States)

    Vugler, Anthony A

    2010-01-01

    Retinal diseases such as age-related macular degeneration and retinitis pigmentosa remain major causes of severe vision loss in humans. Clinical trials for treatment of retinal degenerations are underway and advancements in our understanding of retinal biology in health/disease have implications for novel therapies. A review of retinal biology is used to inform a discussion of current strategies to maintain/repair neural circuitry in age-related macular degeneration, retinitis pigmentosa, and Type 2 Leber congenital amaurosis. In age-related macular degeneration/retinitis pigmentosa, a progressive loss of rods/cones results in corruption of bipolar cell circuitry, although retinal output neurons/photoreceptive melanopsin cells survive. Visual function can be stabilized/enhanced after treatment in age-related macular degeneration, but in advanced degenerations, reorganization of retinal circuitry may preclude attempts to restore cone function. In Type 2 Leber congenital amaurosis, useful vision can be restored by gene therapy where central cones survive. Remarkable progress has been made in restoring vision to rodents using light-responsive ion channels inserted into bipolar cells/retinal ganglion cells. Advances in genetic, cellular, and prosthetic therapies show varying degrees of promise for treating retinal degenerations. While functional benefits can be obtained after early therapeutic interventions, efforts should be made to minimize circuitry changes as soon as possible after rod/cone loss. Advances in retinal anatomy/physiology and genetic technologies should allow refinement of future reparative strategies.

  8. Adaptive Optics Technology for High-Resolution Retinal Imaging

    Science.gov (United States)

    Lombardo, Marco; Serrao, Sebastiano; Devaney, Nicholas; Parravano, Mariacristina; Lombardo, Giuseppe

    2013-01-01

    Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging. PMID:23271600

  9. Scutellaria barbata attenuates diabetic retinopathy by preventing retinal inflammation and the decreased expression of tight junction protein

    Directory of Open Access Journals (Sweden)

    Xi-Yu Mei

    2017-06-01

    Full Text Available AIM: To observe the attenuation of ethanol extract of Herba Scutellaria barbata (SE against diabetic retinopathy (DR and its engaged mechanism. METHODS: C57BL/6J mice were intraperitoneally injected with streptozotocin (STZ, 55 mg/kg for 5 consecutive days to induce diabetes. The diabetic mice were orally given with SE (100, 200 mg/kg for 1mo at 1mo after STZ injection. Blood-retinal barrier (BRB breakdown was detected by using Evans blue permeation assay. Real-time polymerase chain reaction (RT-PCR, Western blot and immunofluorescence staining were used to detect mRNA and protein expression. Enzyme-linked immunosorbent assay (ELISA was used to detect serum contents of tumor necrosis factor-α (TNF-α and interleukin (IL-1β. RESULTS: SE (100, 200 mg/kg reversed the breakdown of BRB in STZ-induced diabetic mice. The decreased expression of retinal claudin-1 and claudin-19, which are both tight junction (TJ proteins, was reversed by SE. SE decreased the increased serum contents and retinal mRNA expression of TNF-α and IL-1β. SE also decreased the increased retinal expression of intercellular cell adhesion molecule-1 (ICAM-1. SE reduced the increased phosphorylation of nuclear factor kappa B (NFκB p65 and its subsequent nuclear translocation in retinas from STZ-induced diabetic mice. Results of Western blot and retinal immunofluorescence staining of ionized calcium-binding adapter molecule 1 (Iba1 demonstrated that SE abrogated the activation of microglia cells in STZ-induced diabetic mice. CONCLUSION: SE attenuates the development of DR by inhibiting retinal inflammation and restoring the decreased expression of TJ proteins including claudin-1 and claudin-19.

  10. Suppressed retinal degeneration in aged wild type and APPswe/PS1ΔE9 mice by bone marrow transplantation.

    Directory of Open Access Journals (Sweden)

    Yue Yang

    Full Text Available Alzheimer's disease (AD is an age-related condition characterized by accumulation of neurotoxic amyloid β peptides (Aβ in brain and retina. Because bone marrow transplantation (BMT results in decreased cerebral Aβ in experimental AD, we hypothesized that BMT would mitigate retinal neurotoxicity through decreased retinal Aβ. To test this, we performed BMT in APPswe/PS1ΔE9 double transgenic mice using green fluorescent protein expressing wild type (wt mice as marrow donors. We first examined retinas from control, non-transplanted, aged AD mice and found a two-fold increase in microglia compared with wt mice, prominent inner retinal Aβ and paired helical filament-tau, and decreased retinal ganglion cell layer neurons. BMT resulted in near complete replacement of host retinal microglia with BMT-derived cells and normalized total AD retinal microglia to non-transplanted wt levels. Aβ and paired helical filament-tau were reduced (61.0% and 44.1% respectively in BMT-recipient AD mice, which had 20.8% more retinal ganglion cell layer neurons than non-transplanted AD controls. Interestingly, aged wt BMT recipients also had significantly more neurons (25.4% compared with non-transplanted aged wt controls. Quantitation of retinal ganglion cell layer neurons in young mice confirmed age-related retinal degeneration was mitigated by BMT. We found increased MHC class II expression in BMT-derived microglia and decreased oxidative damage in retinal ganglion cell layer neurons. Thus, BMT is neuroprotective in age-related as well as AD-related retinal degeneration, and may be a result of alterations in innate immune function and oxidative stress in BMT recipient mice.

  11. Rapid glutamate receptor 2 trafficking during retinal degeneration

    Directory of Open Access Journals (Sweden)

    Lin Yanhua

    2012-02-01

    Full Text Available Abstract Background Retinal degenerations, such as age-related macular degeneration (AMD and retinitis pigmentosa (RP, are characterized by photoreceptor loss and anomalous remodeling of the surviving retina that corrupts visual processing and poses a barrier to late-stage therapeutic interventions in particular. However, the molecular events associated with retinal remodeling remain largely unknown. Given our prior evidence of ionotropic glutamate receptor (iGluR reprogramming in retinal degenerations, we hypothesized that the edited glutamate receptor 2 (GluR2 subunit and its trafficking may be modulated in retinal degenerations. Results Adult albino Balb/C mice were exposed to intense light for 24 h to induce light-induced retinal degeneration (LIRD. We found that prior to the onset of photoreceptor loss, protein levels of GluR2 and related trafficking proteins, including glutamate receptor-interacting protein 1 (GRIP1 and postsynaptic density protein 95 (PSD-95, were rapidly increased. LIRD triggered neuritogenesis in photoreceptor survival regions, where GluR2 and its trafficking proteins were expressed in the anomalous dendrites. Immunoprecipitation analysis showed interaction between KIF3A and GRIP1 as well as PSD-95, suggesting that KIF3A may mediate transport of GluR2 and its trafficking proteins to the novel dendrites. However, in areas of photoreceptor loss, GluR2 along with its trafficking proteins nearly vanished in retracted retinal neurites. Conclusions All together, LIRD rapidly triggers GluR2 plasticity, which is a potential mechanism behind functionally phenotypic revisions of retinal neurons and neuritogenesis during retinal degenerations.

  12. Retinal Detachment

    Science.gov (United States)

    ... to your brain. It provides the sharp, central vision needed for reading, driving, and seeing fine detail. A retinal detachment lifts or pulls the retina from its normal position. It can occur at ...

  13. Coincidence of retinitis pigmentosa and pseudoexfoliative glaucoma

    Directory of Open Access Journals (Sweden)

    Božić Marija

    2017-01-01

    Full Text Available Introduction. This is an observational case report presenting retinitis pigmentosa associated with pseudoexfoliative glaucoma. Case outline. A 69-year-old man presented with retinitis pigmentosa. On examination, pseudoexfoliative material was detected on anterior segment structures, and intraocular pressure was 26 mmHg in the right and 24 mmHg in the left eye. The patient was commenced on topical antiglaucomatous therapy (timolol + dorzolamide twice daily, latanoprost once in the evening to both eyes. Conclusion. To the best of our knowledge, this is the first reported case of retinitis pigmentosa associated with pseudoexfoliative glaucoma. Although rare, retinitis pigmentosa and glaucoma can occur in the same eye.

  14. A PEDF-Derived Peptide Inhibits Retinal Neovascularization and Blocks Mobilization of Bone Marrow-Derived Endothelial Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Richard Longeras

    2012-01-01

    Full Text Available Proliferative diabetic retinopathy is characterized by pathological retinal neovascularization, mediated by both angiogenesis (involving mature endothelial cells and vasculogenesis (involving bone marrow-derived circulating endothelial progenitor cells (EPCs. Pigment epithelium-derived factor (PEDF contains an N-terminal 34-amino acid peptide (PEDF-34 that has antiangiogenic properties. Herein, we present a novel finding that PEDF-34 also possesses antivasculogenic activity. In the oxygen-induced retinopathy (OIR model using transgenic mice that have Tie2 promoter-driven GFP expression, we quantified Tie2GFP+ cells in bone marrow and peripheral blood by fluorescence-activated cell sorting (FACS. OIR significantly increased the number of circulating Tie2-GFP+ at P16, correlating with the peak progression of neovascularization. Daily intraperitoneal injections of PEDF-34 into OIR mice decreased the number of Tie2-GFP+ cells in the circulation at P16 by 65% but did not affect the number of Tie2-GFP+ cells in the bone marrow. These studies suggest that PEDF-34 attenuates EPC mobilization from the bone marrow into the blood circulation during retinal neovascularization.

  15. Exact and Heuristic Solutions to Minimize Total Waiting Time in the Blood Products Distribution Problem

    Directory of Open Access Journals (Sweden)

    Amir Salehipour

    2012-01-01

    Full Text Available This paper presents a novel application of operations research to support decision making in blood distribution management. The rapid and dynamic increasing demand, criticality of the product, storage, handling, and distribution requirements, and the different geographical locations of hospitals and medical centers have made blood distribution a complex and important problem. In this study, a real blood distribution problem containing 24 hospitals was tackled by the authors, and an exact approach was presented. The objective of the problem is to distribute blood and its products among hospitals and medical centers such that the total waiting time of those requiring the product is minimized. Following the exact solution, a hybrid heuristic algorithm is proposed. Computational experiments showed the optimal solutions could be obtained for medium size instances, while for larger instances the proposed hybrid heuristic is very competitive.

  16. Inherited Retinal Degenerative Clinical Trial Network. Addendum

    Science.gov (United States)

    2013-10-01

    inherited orphan retinal degenerative diseases and dry age-related macular degeneration (AMD) through the conduct of clinical trials and other...design and conduct of effective and efficient clinical trials for inherited orphan retinal degenerative diseases and dry AMD; • Limited number and...linica l trial in the NEER network for autosomal dominant retinitis pigmentosa, and the ProgSTAR studies for Stargardt disease ) . As new interventions b

  17. Inner neural retina loss in central retinal artery occlusion.

    Science.gov (United States)

    Ikeda, Fumiko; Kishi, Shoji

    2010-09-01

    To report morphologic retinal changes and visual outcomes in acute and chronic central retinal artery occlusion (CRAO). We reviewed ten eyes of ten patients with CRAO (age, 65.3 ± 10.2 years) and measured retinal thicknesses at the central fovea and the perifovea using optical coherence tomography (OCT) over 8 ± 4 months. During the acute phase (within 10 days), the mean inner retinal thicknesses were 148% and 139% of normal values at 1 mm nasal and temporal to the fovea. They decreased to 22% and 11% of normal inner retinal thickness during the chronic phase (3 months or later). The retinal thickness at the perifovea decreased linearly until 3 months but was stable during the chronic phase. In contrast, the foveal thickness increased slightly in the acute phase but was equivalent to the normal level during the chronic phase. As a result of inner retinal atrophy, the foveal pit was shallow during the chronic phase. The final visual acuity was correlated positively with retinal thickness at the perifovea during the chronic CRAO phase. OCT showed that inner retinal necrosis with early swelling and late atrophy occurred in CRAO. The fovea and outer retina appeared to be excluded from ischemic change. The residual inner retina at the perifovea determined the final visual outcomes.

  18. Multiple evanescent white dot syndrome associated with retinal vasculitis

    Directory of Open Access Journals (Sweden)

    Takahashi A

    2015-09-01

    Full Text Available Akihiro Takahashi, Wataru Saito, Yuki Hashimoto, Susumu Ishida Department of Ophthalmology, Hokkaido University Graduate School of Medicine, Sapporo, Japan Purpose: A recent study revealed thickening of the inner retinal layers in acute stage of multiple evanescent white dot syndrome (MEWDS; however, the pathogenesis is still unknown. We report two cases with MEWDS whose funduscopy showed obvious retinal vasculitis. Methods: Case reports. Results: Healthy myopic 16- and 27-year-old women were the cases under study. In both cases, funduscopic examination revealed multiple, faint, small, subretinal white dots at the posterior pole to the midperiphery and macular granularity oculus dexter. Retinal vascular sheathing was also observed at midperiphery. Late-phase fluorescein angiography revealed leakages corresponding to the vascular sheathing. Enhanced depth imaging optical coherence tomography revealed the discontinuity of the ellipsoid zone corresponding to the white dots and increased macular choroidal thickness. One month later, these white dots and retinal sheathing spontaneously resolved in both cases. Three months later, impairments of the outer retinal morphology and the visual acuity were restored. Conclusion: These results suggest that retinal vasculitis possibly plays a role in the pathogenesis of thickened inner retinal layers in acute stage of MEWDS. Keywords: enhanced depth imaging optical coherence tomography, choroidal thickness, inner retinal layer, retinal vascular sheathing

  19. Mitochondrial dysfunction underlying outer retinal diseases

    DEFF Research Database (Denmark)

    Lefevere, Evy; Toft-Kehler, Anne Katrine; Vohra, Rupali

    2017-01-01

    Dysfunction of photoreceptors, retinal pigment epithelium (RPE) or both contribute to the initiation and progression of several outer retinal disorders. Disrupted Müller glia function might additionally subsidize to these diseases. Mitochondrial malfunctioning is importantly associated with outer...

  20. Intra-articular injection of tranexamic acid via a drain plus drain-clamping to reduce blood loss in cementless total knee arthroplasty

    Directory of Open Access Journals (Sweden)

    Mutsuzaki Hirotaka

    2012-09-01

    Full Text Available Abstract Background Patients undergoing cementless total knee arthroplasty (TKA sometimes suffer large blood loss. In a retrospective study, we explored whether postoperative intra-articular retrograde injection of tranexamic acid (TA and leaving a drain clamp in place for 1 h reduced blood loss. Patients and methods Patients (n = 140 treated with unilateral primary cementless TKA (posterior cruciate ligament retained were divided into two groups: those who had an intra-articular injection of TA (1000 mg and drain clamping for 1 h postoperatively (study group, n = 70 and those who were not given TA and did not undergo clamping of their drains (control group, n = 70. Postoperative total blood loss, volume of drainage, hemoglobin level, transfusion amounts and rates, D-dimer level at postoperative day (POD 7, and complications were recorded. Results Total blood loss, total drainage, mean transfusion volume, and transfusion rates were lower in the study group than in controls (P P P  Conclusions Immediately postoperative intra-articular retrograde injection of TA and 1 h of drain-clamping effectively reduced blood loss and blood transfusion after cementless TKA. We believe that this method is simple, easy, and suitable for these patients.