Neurovascular Coupling in Patients With Early Stage Diabetes Retinopathy
Summary
A variety of studies demonstrate that ocular blood flow is altered in diabetes and retinal perfusion abnormalities have been proposed to contribute to the pathogenesis of diabetic retinopathy.
Various animal and human studies have demonstrated that retinal and optic nerve blood flow increase in response to diffuse luminance flicker. Based on studies with ERG, this effect has been attributed to augmented activity in the retinal ganglion cells and associated axons indicating a coupling mechanism between neuronal activity and retinal blood flow. Whereas a variety of studies describe the effects of flickering light on retinal and optic nerve head blood flow, the knowledge about this coupling in the diabetic retina is sparse.
In view of the fact that neural activity and blood flow are strongly coupled in the human retina, one could hypothesize that neurodegenerative changes in the retina could contribute to the vascular dysregulation and in turn lead to changes of ocular perfusion. The investigators set out to investigate whether the coupling of neural activity and blood flow is impaired in patients with early stage diabetic retinopathy compared to those in healthy volunteers.
Study Design
N/A
Conditions
Diabetic Retinopathy
Intervention
Ocular blood flow measurements
Location
Department of Clinical Pharmacology, Medical University of Vienna
Vienna
Austria
1090
Status
Recruiting
Source
Medical University of Vienna
Results (where available)
Links
- Source: http://clinicaltrials.gov/show/NCT00712842
- Information obtained from ClinicalTrials.gov on July 15, 2010
Medical and Biotech [MESH] Definitions
Fluorophotometry
Measurement of light given off by fluorescein in order to assess the integrity of various ocular barriers. The method is used to investigate the blood-aqueous barrier, blood-retinal barrier, aqueous flow measurements, corneal endothelial permeability, and tear flow dynamics.
Vitreoretinal Surgery
Specialized ophthalmic technique used in the surgical repair and or treatment of disorders that include retinal tears or detachment; MACULAR HOLES; hereditary retinal disease; AIDS-related retinal infections; ocular tumors; MACULAR DEGENERATION; DIABETIC RETINOPATHY; and UVEITIS.
Calcium Dobesilate
A drug used to reduce hemorrhage in diabetic retinopathy.
Vitrectomy
Removal of the whole or part of the vitreous body in treating endophthalmitis, diabetic retinopathy, retinal detachment, intraocular foreign bodies, and some types of glaucoma.
Diabetic Neuropathies
Peripheral, autonomic, and cranial nerve disorders that are associated with DIABETES MELLITUS. These conditions usually result from diabetic microvascular injury involving small blood vessels that supply nerves (VASA NERVORUM). Relatively common conditions which may be associated with diabetic neuropathy include third nerve palsy (see OCULOMOTOR NERVE DISEASES); MONONEUROPATHY; mononeuropathy multiplex; diabetic amyotrophy; a painful POLYNEUROPATHY; autonomic neuropathy; and thoracoabdominal neuropathy. (From Adams et al., Principles of Neurology, 6th ed, p1325)
Clinical Trials
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Octreotide Acetate in Microspheres in Patients With Diabetic Retinopathy
The most common ocular disease in patients with diabetes, diabetic retinopathy, is present in approximately 40% of diabetic patients; about 8% of diabetic patients have vision threatening...
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Effects of Moxaverine and Placebo on Ocular Blood Flow
A number of common eye diseases such as retinal artery and vein occlusion, diabetic retinopathy, age-related macular degeneration, glaucoma and anterior ischemic optic neuropathy are assoc...
PubMed Articles
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We evaluated tele-ophthalmology for diabetic retinopathy screening in a primary care setting. Four general practitioners (GPs) were taught to assess non-mydriatic retinography images of patients with...
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Aldose Reductase / Polyol Inhibitors For Diabetic Retinopathy.
Diabetic retinopathy is the most common microvascular complication of diabetes and the most severe of diabetic ocular complications. This review describes retinal changes at different stages of diabet...
