alexa Interaction between flicker-induced vasodilatation and pressure autoregulation in early retinopathy of Type 2 diabetes
Ophthalmology

Ophthalmology

Journal of Clinical & Experimental Ophthalmology

Author(s): Bek T, Hajari J, Jeppesen P

Abstract Share this page

Background Diabetic retinopathy is accompanied with changes in the autoregulation of retinal blood flow secondary to changes in the systemic blood pressure and the retinal metabolism. In the present study we tested the working hypothesis that there is an interaction between these mechanisms that might be relevant for understanding and treating flow disturbances in diabetic retinopathy. Methods Fifty-four persons divided into three age and sex matched groups were studied: Group 1: twenty normal persons. Group 2: fourteen patients with type 2 diabetes mellitus and no diabetic retinopathy. Group 3: twenty type 2 diabetic patients with minimal diabetic retinopathy and a diabetes duration similar to that of the patients in group 2. Using the Retinal Vessel Analyzer (RVA) the diameter response of retinal arterioles was studied in all groups after an increase in the blood pressure by isometric exercise, during exposition to 8 Hz flickering light, and during simultaneous exposition to both stimulus conditions. Results The increased blood pressure induced by isometric exercise induced a non-significant vasoconstriction in the normal persons and in the diabetic patients without retinopathy (p = 0.10 and p = 0.84 respectively), and a non-significant vasodilatation in the diabetic patients with mild retinopathy (p = 0.10). The flicker stimulus elicited a significant vasodilatation of retinal arterioles that decreased significantly from the normal persons to the diabetic patients without and with retinopathy (linear regression, p < 0.01). The flicker-induced vasodilatation was not significantly affected by a simultaneous increase in the arterial blood pressure in normal persons (p = 0.85). Conversely, in the diabetic patients the reduced diameter response during flicker was counteracted by a simultaneous increase in the blood pressure, to a level not differing significantly from the response of normal persons (p = 0.75). Conclusions Intervention studies aimed at modifying perfusion in retinal disease should consider the interaction between different mechanisms for autoregulating retinal blood flow. New treatment modalities for retinal vascular disease might need to target several mechanisms of tone control in retinal arterioles simultaneously.

This article was published in Graefe's Archive for Clinical and Experimental Ophthalmology and referenced in Journal of Clinical & Experimental Ophthalmology

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords