Coupling of Neural Activity and Retinal Blood Flow in Diabetes
The prevalence of diabetes is increasing and the management of the disease is nowadays considered a major challenge. Affected patients have increased mortality and morbidity as well as a significant drop in the quality of life. The complications of diabetes can be classified as microvascular (e.g. nephropathy, neuropathy or retinopathy) or macrovascular (e.g. cardiovascular or cerebrovascular).
Several large-scale epidemiologic studies indicating that wider retinal venous caliber is strongly associated with the fasting glucose level as well as with diabetes. Another retinal vascular abnormality that is associated with diabetes is an abnormal retinal vascular response to flicker stimulation. Retinal vessel dilatation in response to stimulation with diffuse flicker light occurs due to a phenomenon called neurovascular coupling. This means that increased activity of neurons is associated with an increased retinal metabolism. This leads to a release of endogenous vasodilator substances and increased blood flow. However, previous studies were limited by the fact that retinal vessel diameters and blood flow were not measured simultaneously.
The present study aims to investigate whether the response of retinal vessel diameters and blood flow velocities to flicker stimulation is altered in patients with diabetes. Both parameters will be measured in real time using Fourier Domain Doppler OCT.
|Study Design:||Observational Model: Case Control
Time Perspective: Prospective
- Retinal vessel diameters [ Time Frame: 18 months ] [ Designated as safety issue: No ]
- Retinal blood flow velocities [ Time Frame: 18 months ] [ Designated as safety issue: No ]
|Study Start Date:||March 2013|
|Estimated Study Completion Date:||January 2016|
|Estimated Primary Completion Date:||December 2015 (Final data collection date for primary outcome measure)|
Patients with early insulin dependent diabetes and no or mild non-proliferative retinopathy
healthy control subjects
Please refer to this study by its ClinicalTrials.gov identifier: NCT01375166
|Contact: Gerhard Garhöfer, MD||0043 1 40400 ext firstname.lastname@example.org|
|Department of Clinical Pharmacology||Recruiting|
|Vienna, Austria, 1090|
|Principal Investigator:||Gerhard Garhöfer, MD||Department of Clinical Pharmacology, Medical University of Vienna|