Digital Retinal Images (digital + retinal_image)

Distribution by Scientific Domains


Selected Abstracts


Microvascular lesions in the brain and retina: The age, gene/environment susceptibility,Reykjavik study,

ANNALS OF NEUROLOGY, Issue 5 2009
Chengxuan Qiu MD
Objective To investigate whether the severity and location of cerebral white matter hyperintensities (WMHs) and brain infarcts are correlated with the signs of retinal microvascular abnormalities in the elderly. Methods The study included 4,176 men and women (mean age, 76 years) who participated in the Age, Gene/Environment Susceptibility (AGES),Reykjavik Study. Digital retinal images of both dilated eyes were taken and evaluated for the presence of retinal focal arteriolar signs (focal arteriolar narrowing and arteriovenous nicking) and retinopathy lesions (retinal blot hemorrhages and microaneurysms). Brain magnetic resonance imaging scans were acquired and evaluated for the presence and distribution of cerebral infarcts and WMHs. Logistic and multinomial logistic models were constructed to estimate the association of retinal microvascular signs to brain lesions. Results Controlling for demographic and major cardiovascular risk factors, we found that retinal focal arteriolar signs, but not retinopathy lesions, were significantly associated with an increasing load of subcortical and periventricular WMHs. The strongest association was found between retinal arteriolar signs and a heavier WMH load, specifically in the subcortical frontal lobe, and periventricular frontal and parietal caps. There was a tendency toward bilateral retinal focal arteriolar narrowing being more strongly associated with the heavier load of subcortical WMHs. Arteriovenous nicking was significantly associated with subcortical infarcts. Interpretation In older adults, retinal focal arteriolar signs, but not retinopathy lesions, are correlated with the load of diffuse WMHs, particularly those located in the subcortical frontal lobe, and the periventricular frontal and parietal caps of the brain. Ann Neurol 2009;65:569,576 [source]


Feasibility of using the TOSCA telescreening procedures for diabetic retinopathy

DIABETIC MEDICINE, Issue 10 2004
S. Luzio
Abstract Aims The TOSCA project was set up to establish a tele-ophthalmology service to screen for diabetic retinopathy (DR) in Europe. The aim of this study was to determine the feasibility of establishing telemedicine-based digital screening for detecting DR and to evaluate the satisfaction of both patients and healthcare professionals with the screening procedures used within the TOSCA project. Methods The study was a non-randomized, multicentre study carried out in four different countries over a period of 3 months. Patients (n = 390) with diabetes aged > 12 years were included. Two digital retinal images per eye (macular and nasal) were taken and exported to a central server. Patients were asked to complete a questionnaire to assess satisfaction. Accredited graders carried out grading remotely and the results were reported back to the referring centre. Previously graded patient data chosen randomly to represent examples of both DR and no DR were also sent anonymously to the grading centre at a frequency of approximately every 10 patients. Results Most (99%) of the images were assessable enabling a retinopathy grade to be assigned to the patient. Patients found the retinal photography procedures acceptable; only 6% in one centre would not recommend the procedure. Healthcare professionals (photographers and graders) were also satisfied with the overall procedures. The average time taken to grade each patient was approximately 5 min. Conclusions This study demonstrated that it is feasible to electronically transmit and grade retinal images remotely using the TOSCA process. Built-in quality assurance procedures proved acceptable. [source]


Frequency of Fish Consumption, Retinal Microvascular Signs and Vascular Mortality

MICROCIRCULATION, Issue 1 2008
Shweta Kaushik BMed (Hons)
ABSTRACT Objective: Fish consumption has established cardiovascular and cerebrovascular benefits, but its effects on microvascular structure have not been examined in population-based studies. We investigated this association, in relation to vascular mortality in an Australian cohort (1992,2004). Methods: Of 3654 participants aged 49+ years, 2683 (73%) with available data were included. Retinal arteriolar and venular diameters were measured, and signs of arterio-venous nicking and retinopathy were assessed from digital retinal images. Fish consumption was evaluated using a food frequency questionnaire. Results: Both wider mean arteriolar diameter (p = 0.002) and narrower venular diameter (p = 0.02) were associated with increasing frequency of consuming any or oily fish, after adjusting for cardiovascular risk factors, diet, inflammatory factors and socioeconomic status. This association was mainly present in persons with hypertension. Greater frequency of fish consumption was associated with a reduced prevalence of arterio-venous nicking and a borderline significant trend for reduced retinopathy prevalence. Ten year stroke-related mortality was significantly lower in persons consuming fish at least once per week compared to less frequent consumption (hazard ratio 0.57, 95% CI: 0.35 to 0.93). Conclusions: Recent evidence shows that narrower arterioles and wider venules may predict vascular events. Our new findings suggest that the vascular protective effects of consuming fish could act, in part, by preventing pathological microvasculature change. [source]


Retinal arterioles have impaired reactivity to hyperoxia in type 1 diabetes

ACTA OPHTHALMOLOGICA, Issue 4 2010
Birgitte L. Justesen
Abstract. Purpose:, Diabetes has adverse effects on the retinal microvasculature. The purpose of this study was to compare the effects of inhalation of hypoxic, hyperoxic and normoxic,hypercapnic gas mixtures on retinal vessel diameter in people with and without diabetes. Methods:, Sixty-one participants (aged 24,50 years) 29 with (male : female ratio 2.6 : 1) and 32 without (male : female ratio 0.7 : 1) diabetes, inhaled hypoxic, hyperoxic and normoxic,hypercapnic gas mixtures for 3,5 mins. The diameters of arterioles and venules were measured using digital retinal images taken before and after gas inhalation. Results:, There was no significant difference in the diameters of arterioles and venules prior to gas inhalation in people with and without diabetes. Inhalation of the hyperoxic gas mixture caused a statistically significant decrease in arteriolar and venular diameters without altering mean arterial pressure significantly. Arteriolar vasoconstriction in response to the hyperoxic gas mixture was significantly reduced in people with diabetes (3.95% versus 7.75%; p = 0.04), but venular vasoconstriction did not differ significantly. A hypoxic gas mixture caused increased arteriolar and venular diameter and a normoxic,hypercapnic gas mixture had no significant effect on vessel diameter. Responses to hypoxic and normoxic,hypercapnic gas did not differ significantly between diabetes and non-diabetes subjects. Conclusions:, Type 1 diabetes impairs retinal arteriolar responses to hyperoxia. Abnormalities in retinal arteriolar reactivity in response to oxygen may play a role in the development of diabetic retinopathy and this technique may represent a simple means of identifying early abnormalities in the reactivity of retinal arterioles in diabetes. [source]