Optical coherence tomography fast versus regular macular thickness mapping in diabetic retinopathy

Objective: The purpose of the study was to investigate if absolute values and reproducibility of thickness maps obtained from 2 optical coherence tomography (OCT) scanning protocols, regular high-resolution and fast low-density mode, differ in patients with diabetic macular edema. Methods: A total of 26 consecutive patients undergoing fluorescein angiography and Stratus OCT scanning for the evaluation of diabetic macular edema at the Departments of Ophthalmology in Munich and Vienna were included. Results: Retinal thickness of the central field of the thickness map measured by fast retinal thickness protocol was 287 +/- 97 and 290 +/- 113 mu m by the regular protocol. This difference as well as that for all other fields was not statistically significant. Three times repeated measurements applying both OCT scanning modes in 10 patients yielded very good intrasession correlation coefficients between 0.70 and 0.99, with corresponding intrasession standard deviations ranging between 6 and 16 mu m. The fast mode yielded slightly less reproducible values than the regular mode. Visual acuity did not influence the results. Conclusion: In practice both scanning modes caninterchanged and absolute values can be compared directly. Best reproducibility is obtained with higher sampling density even in patients with reduced visual acuity due to diabetic macular edema. Copyright (C) 2008 S. Karger AG, Basel

Minocycline is cytoprotective in human corneal endothelial cells and induces anti-apoptotic B-cell CLL/lymphoma 2 (Bcl-2) and X-linked inhibitor of apoptosis (XIAP)

Introduction Loss of corneal endothelial cells (CECs) is one major factor limiting transplant clarity and survival after keratoplasty. Amongst other factors, apoptosis due to cellular stress is responsible for these problems. This study investigates the possible anti-apoptotic and cytoprotective effects of minocycline on a human corneal endothelial cell line (HCEC-SV40) cultured under oxidative stress and with transforming growth factor beta (TGF-beta). Methods CECs were treated with 1-150 mM minocycline. Cell viability and the median inhibitory concentration (IC(50)) were evaluated after 48 h and after H(2)O(2) treatment (tetrazolium dye reduction assay and liveedead assay). Expression of B-cell CLL/lymphoma 2 (Bcl-2) and X-linked inhibitor of apoptosis (XIAP) and their mRNA were assessed by reverse transcriptase (RT)-PCR and western blot analysis after treatment with minocycline alone and consecutive incubation with 200 mM H(2)O(2) and TGF-beta 2. A quantitative detection of histone-associated DNA fragmentation by ELISA was performed. Results Minocycline concentrations from 1-50 mM showed no toxic effects on CECs. Pre-treatment with 10-40 mM minocycline led to an increase in viability after H(2)O(2) treatment. In addition, minocycline pretreatment attenuated the increase of histone-associated DNA fragmentation after treatment with H(2)O(2) and TGF-beta 2 significantly. When CECs were treated with minocycline and then consecutively with H(2)O(2) or TGF-beta 2, RT-PCR and western blot analysis yielded an overexpression of Bcl-2 and XIAP. Conclusion In this study minocycline prevented apoptotic cell death in cultured CECs in vitro. Our results suggest that minocycline might offer cytoprotective properties that might help to prevent loss of corneal endothelial cells in vivo

Comparison of Intravitreal Bevacizumab versus Triamcinolone for the Treatment of Diffuse Diabetic Macular Edema

Background: Our purpose was to compare the effect of triamcinolone and bevacizumab (Avastin) on the retinal thickness and functional outcome in patients with diabetic macular edema. Methods and Materials: A collective of 32 patients, who had been treated by a single 4.0-mg intravitreal triamcinolone injection (group 1), was matched to 32 patients ('matched pairs'), who had received 3 injections of 1.25 mg of bevacizumab within 3 months in 4-week intervals (group 2). The outcome variables were changes in best corrected visual acuity (VA) and central retinal thickness 3 months after therapy. Results: Both groups did not differ regarding preoperative VA and central retinal thickness measured by optical coherence tomography. The baseline mean VA was 0.72 +/- 0.39 logMAR in group 1 and 0.73 +/- 0.39 logMAR in group 2 (p = 0.709). The mean central retinal thickness measured by optical coherence tomography was 548 +/- 185 mu m in group 1 and 507 +/- 192 mu m in group 2. While the patients in group 1 experienced a slight increase in VA of on average 0.7 lines following a single triamcinolone injection to a mean of 0.64 +/- 0.40 logMAR (p = 0.066) after 3 months, the patients in group 2 showed almost no effect on VA with an average increase of 0.2 lines to a mean VA of 0.72 +/- 0.30 logMAR (p = 0.948) following 3 intravitreal injections of bevacizumab. Comparing the effect on VA between both groups no statistically significant difference (p = 0.115) was noted. Concerning decrease in central retinal thickness both therapies were highly effective (p < 0.001 each), again, without statistically significant difference between the groups (p < 0.128). Conclusion: Our data suggest that a single triamcinolone injection may be as effective as a 3 times repeated intravitreal administration of bevacizumab for the treatment of diabetic macular edema. Further prospective trials should be performed. Copyright (C) 2010 S. Karger AG, Base

Obesity and the microvasculature

Overweight and obesity are thought to significantly influence a person's risk of cardiovascular disease, possibly via its effect on the microvasculature. Retinal vascular caliber is a surrogate marker of microvascular disease and a predictor of cardiovascular events. The aim of this systematic review and meta-analysis was to determine the association between body mass index (BMI) and retinal vascular caliber. Relevant studies were identified by searches of the MEDLINE and EMBASE databases from 1966 to August 2011. Standardized forms were used for data extraction. Among over 44,000 individuals, obese subjects had narrower arteriolar and wider venular calibers when compared with normal weight subjects, independent of conventional cardiovascular risk factors. In adults, a 1 kg/m(2) increase in BMI was associated with a difference of 0.07 μm [95% CI: -0.08; -0.06] in arteriolar caliber and 0.22 μm [95% CI: 0.21; 0.23] in venular caliber. Similar results were found for children. Higher BMI is associated with narrower retinal arteriolar and wider venular calibers. Further prospective studies are needed to examine whether a causative relationship between BMI and retinal microcirculation exists

Obesity and the Microvasculature: A Systematic Review and Meta-Analysis

10.1371/journal.pone.0052708PLoS ONE82

Association between overweight (BMI between 25.0 and 29.9 kg/m²) and CRAE (<i>A</i>), and CRVE (<i>B</i>) in adults (maximum level of adjustment).

<p>Association between overweight (BMI between 25.0 and 29.9 kg/m²) and CRAE (<i>A</i>), and CRVE (<i>B</i>) in adults (maximum level of adjustment).</p

Flow-chart identifying eligible studies.

<p>Flow-chart identifying eligible studies.</p

Association between obesity (BMI >30.0 kg/m²) and CRAE (<i>A</i>), and CRVE (<i>B</i>) in adults (maximum level of adjustment).

<p>Association between obesity (BMI >30.0 kg/m²) and CRAE (<i>A</i>), and CRVE (<i>B</i>) in adults (maximum level of adjustment).</p

Characteristics of studies included in the meta-analysis.

<p>Characteristics of studies included in the meta-analysis.</p