Purchase this article with an account.
Lee-Anne Khuu, Olena Puzyeyeva, John G. Flanagan, Chris Hudson; Retinal Vascular Regulation and Intraocular Pressure in Non-Proliferative Diabetic Retinopathy. Invest. Ophthalmol. Vis. Sci. 2011;52(14):1290.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To evaluate the association between functional vascular regulation in the retinal arterioles and baseline IOP in healthy controls and patients with type 2 diabetes and non-proliferative diabetic retinopathy (NPDR).
The sample consisted of 11 control subjects (mean age 55±10yrs) and 33 patients with type 2 diabetes and NPDR. Diabetic patients were divided into mild-to-moderate (n=23, 61±8yrs) and moderate-to-severe (n=10, 64±9yrs) NPDR. Goldmann IOP was measured prior to evaluation of retinal hemodynamics. Arteriolar diameter, velocity and blood flow were assessed in the supero-temporal arteriole using the Canon Laser Blood Flowmeter. Vascular regulation was assessed using an isocapnic hyperoxic provocation. Retinal vascular reactivity (VR) was quantified as the difference in hemodynamic parameters between baseline and isocapnic hyperoxic provocation and expressed as percentage change from baseline.
There were no significant differences between groups in terms of the VR response in diameter, blood velocity and blood flow. IOP was not significantly different between groups (ANOVA p=0.14). A1c significantly increased across the 3 groups (ANOVA p<0.01). Bivariate Pearson correlation showed that the magnitude of VR in terms diameter was weakly associated with IOP (r=-0.32, p=0.03) across all groups and showed a similar weak relationship across the 2 diabetic groups (r=-0.39, p=0.02). Within the mild-to-moderate NPDR group, VR in terms of vessel diameter and blood velocity was moderately associated with IOP (diameter: r=-0.46, p=0.02; velocity: r=0.40, p=0.05).
The results of this study suggest vascular dysregulation and IOP are moderately associated in patients with mild-to-moderate NPDR. The retinal vessels constrict less to hyperoxic provocation with increasing IOP and, as a result, reduction in velocity is not as great with increasing IOP.
This PDF is available to Subscribers Only