Retinal Venous Pressure and ET-1 in Patients With Diabetes Mellitus
Measurement of the circulation in patients with diabetes mellitus and establish a link between retinal venous pressure (RVP) and endothelin (ET-1)levels.
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||Measurement of Retinal Venous Pressure and Endothelin-1 in Patients With Diabetes Mellitus|
- Quantification of retinal venous pressure (RVP) [ Time Frame: 30 minutes ] [ Designated as safety issue: No ]
- Quantification of ET-1 in correlation with RVP [ Time Frame: 30 minutes ] [ Designated as safety issue: No ]
|Study Start Date:||August 2011|
|Study Completion Date:||November 2012|
|Primary Completion Date:||September 2012 (Final data collection date for primary outcome measure)|
Patients with diabetes mellitus type I + II, without diabetic retinopathy
Diabetic retinopathy and maculopathy are the main causes of visual loss. Hyperglycemia as the main risk factor of diabetic retinopathy induced damage to retinal capillaries. These in turn lead to hypoxia in the tissue and promote the release of VEGF (vascular endothelial growth factor) , which in turn increases the vascular pathology. Simultaneously, there is an increased expression of endothelin (ET-1). Endothelin increases vascular tone and regulates the micro-and macro-vascular remodeling.
In ocular blood flow perfusion pressure plays an important role. While in healthy eyes a spontaneous retinal venous pulsation is frequently observed, this is significantly less frequent in diseased eyes. An increased venous pressure lowers the ocular perfusion pressure, and increases the transmural pressure. A measurement of the retinal venous pressure and the hormone ET-1 in the blood will give us a better knowledge of the circulatory changes and their relationship to diabetes.
|University of Basel, Dept. of Ophthalmology|
|Basel, Switzerland, 4031|
|Study Director:||Josef Flammer, MD||University of Basel, Dept. of Ophthalmology|