Abstract
Purpose :
To ask whether arterial wall thickening is consequent to local diabetic retinal conditions.Thickening of the arteriolar walls occur as a function of aging, hypertension and diabetes. Because diabetes and hypertension often occur in a single patient, we ask whether there is an additional change to arteriolar walls attributable to diabetes by comparing retinal vascular changes between more and less affected areas within the same retina
Methods :
Diabetic subjects (12) were selected based on having local areas of diabetic retinal change. All subjects signed an approved informed consent. All patients were dilated and received a clinical examination and an SD-OCT (Spectralis, Heidelberg, Germany). All patients were imaged using the Indiana AOSLO
A series of small, 528-microns x 600-microns, regions were imaged. Imaged regions were then divided into 2 groups for each subject. Group1 regions included involved areas that showed more than 1 sign of clinically detectable diabetic retinopathy (microaneurysms, hard and soft exudates, hemorrhage and/or neovascularization) or non clinically detectable but AOSLO visible signs of diabetic retinopathy (focal capillary closure, microaneurysms or other microvascular abnormalities). Group2 regions appeared normal by the above criteria
All images were uploaded to Photoshop and at each vessel location five measurements of vascular lumen and overall diameter were averaged and wall-to-lumen ratio (WLR) was calculated. A total of 58 arterioles were identified in group1 and 31 in group2. The vessels were then divided into small(< 50 microns) and large(> 50 microns)subgroups. For ANOVA analysis vessel averages for each patient's subgroups were computed and then the averges for each patients were compared
Results :
Arterioles in Group1 had more abnormalities in their vascular walls, including local wall thickning. Group 1 WLR’s were 0.91 and 1.1(larger and smaller respectively) and Group2 WLR’s were 0.32 and 0.68. These differed significantly (ANOVA p<0.05)
Conclusions :
The thickening of vascular walls measured in diabetes seems to include a local component with the walls being relatively thicker in involved regions. This suggests that the vascular consequences of diabetes are not uniform throughout the retina. The question remains as to whether these findings of local vascular wall changes are the cause of these surrounding compromised areas or the consequence of it
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.