Search results for "Retinal Vessels"

Endothelial Dab1 signaling orchestrates neuro-glia-vessel communication in the central nervous system.

2018

Developing the bloodbrain barrier During development, signals need to be dynamically integrated by endothelial cells, neurons, and glia to achieve functional neuro-glia-vascular units in the central nervous system. During cortical development, neuronal Dab1 and ApoER2 receptors respond to a guidance cue called reelin. Studying mice, Segarra et al. found that Dab1 and ApoER2 are also expressed in endothelial cells (see the Perspective by Thomas). The integration of reelin signaling in endothelial cells and neurons facilitates the communication between vessels, glia, and neurons that is necessary for the correct positioning of neurons during cortical development. This integration is also impo…

Accurate estimation of retinal vessel width using bagged decision trees and an extended multiresolution Hermite model.

2012

We present an algorithm estimating the width of retinal vessels in fundus camera images. The algorithm uses a novel parametric surface model of the cross-sectional intensities of vessels, and ensembles of bagged decision trees to estimate the local width from the parameters of the best-fit surface. We report comparative tests with REVIEW, currently the public database of reference for retinal width estimation, containing 16 images with 193 annotated vessel segments and 5066 profile points annotated manually by three independent experts. Comparative tests are reported also with our own set of 378 vessel widths selected sparsely in 38 images from the Tayside Scotland diabetic retinopathy scre…

Retinal vessel analysis and heart rate variability

2014

Heart rate variability (HRV) is used to index the vegetative nervous system and is linked with cardiovascular and nervous diseases [1]. Funduscopic assessment of the retinal vasculature can be utilized to evaluate the health status of microcirculation and to assess the predisposition of major vascular diseases [2]. The purpose of this study was, for the first time, to examine the influence of HRV on microcirculation as an early marker of cardiovascular alteration. The study population was comprised of apparently healthy employees of a high-tech company in Germany. The participants spanned the entire age of the work force (18–65 years) and all levels of socioeconomic status. A total of 292 s…

Computer assisted evaluation of retinal vessels tortuosity in Fabry disease.

2012

. Purpose:  Fabry Disease (FD) is a rare X-linked metabolic disorder characterized by diffuse deposition of sphingolipids in many tissues. Retinal vessel tortuosity is a common ocular manifestation in FD and may represent a useful marker for the disease. Unfortunately its clinical evaluation is poorly reproducibile and alternative means of evaluation may be of interest. We tested a new semi-automatic software measuring retinal vessel tortuosity from eye fundus digital images in a group of FD patients. Methods:  Observational case-control study evaluating four mathematical parameters describing tortuosity (relative length, sum of angle metric [SOAM], product of angle distance [PAD], triangul…

Immunohistochemical analysis of cellular adhesion molecules (ICAM-1, VCAM-1) and VEGF in fibrovascular membranes of patients with proliferative diabe…

2009

Abstract Purpose Diabetic fibrovascular membranes are the main pathological changes of proliferative diabetic retinopathy that can cause serious complications leading to blindness. Since the mechanism of fibrovascular membrane development is still unknown, the aim of our study was to identify potential biomarkers for this pathology. To this end, we analyzed the simultaneous expression of ICAM-1, VCAM-1 and VEGF within tissues of diabetic fibrovascular membranes. Patients and methods Fibrovascular membranes were taken from nine diabetic patients with proliferative diabetic retinopathy. The fibrovascular membrane specimens were analyzed by immunohistochemistry to determine ICAM-1, VCAM-1 and …

Birthweight and its association with retinal vessel equivalents – Results from the population‐based German Gutenberg Health Study

2020

Associations of cardiovascular risk factors and retinal vessel dimensions at present and their evolution over time in a healthy working population.

2019

Purpose The aim of this study was to investigate whether an association between retinal vessel diameters with blood pressure and other risk factors exists in a healthy working population and whether current risk factors can be used as predictors for retinal vessel changes over time. Methods Retinal photographs and medical data were obtained during a voluntary work health check in 2010 and 2013. The central retinal arterial equivalent (CRAE) and central retinal venular equivalent (CRVE) were assessed using a semi-automated software. Linear regression analysis was carried out to determine associations with systemic parameters and cardiovascular risk factors. Results A total of 1685 participan…

Pilot study for the evaluation of morphological and functional changes in retinal blood flow in patients with insulin resistance and/or type 2 diabet…

2012

Background: The aim of this study was to investigate early morphological and functional pathology in the retinal micro-circulation in patients with insulin resistance and/or type 2 diabetes mellitus (T2DM). Methods: Fifty-four subjects, without features of retinopathy under ophthalmological investigation, were recruited for study participation and were classifed into three study groups according to their metabolic staging: (1) Group C comprised nondiabetic, insulin-sensitive subjects with a BMI <28kg/m2; (2) Group IR comprised nondiabetic, insulin-resistant, obese subjects with a BMI ≥28 kg/m2; and (3) Group DM comprised patients with manifested T2DM. Retinal microvascular blood flow was…

A retinal snap shot may indicate individual risk for cardiovascular disease — The MIPH Eye&Health Study

2014

Examination of retinal vasculature can be used to non-invasively quantify changes within the microvasculature of the human body and might be a predictor of cardiovascular disease. This study evaluates associations of the structure of the retinal vasculature with established risk factors for cardiovascular disease.A cross-sectional study was performed in a working age population. Several systemic cardiovascular parameters were analyzed and PROCAM- and SCORE-risk estimates were calculated. A quantitative ophthalmological examination including digital fundus imaging has taken place. Central retinal arterial/venous equivalents (CRAE/CRVE) and arterio-venous ratio (AVR) were analyzed using valid…

Microalbuminuria, renal dysfunction and cardiovascular complication in essential hypertension

1996

To evaluate the prevalence of microalbuminuria (albumin excretion rate, AER) in a wide hypertensive population, and to evaluate any relationship with cardiovascular damage and renal dysfunction.A transversal study.In 383 hospitalized Caucasian essential hypertensives (198 men, 185 women) of mean age 44 +/- 0.5 years and mean clinic blood pressure 170.3 +/- 0.95/ 103.4 +/- 0.47 mmHg, metabolic parameters, serum creatinine level (Cs), creatinine clearance rate (Ccs), 24 AER and plasma renin activity (PRA) were measured. Furthermore, each patient underwent 24 h ambulatory blood pressure monitoring (ABPM) and echocardiography to measure left ventricular mass, which was indexed both by body surf…