Purchase this article with an account.
Richard Donald Bavier, Moataz M Razeen, Alexander Gan, Alexander Pinhas, Nishit Shah, Eric Cheang, Chun Lin Liu, Toco Yuen Ping Chui, Alfredo Dubra, Richard B Rosen; In Vivo Microscopic Assessment Of Perfused Foveal Capillary Lumen Diameters In Diabetic Retinopathy Versus Healthy Controls. Invest. Ophthalmol. Vis. Sci. 2014;55(13):2602.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To measure the lumen diameter of perfused capillaries surrounding the foveal avascular zone (FAZ) and assess the variability in diabetic retinopathy (DR) versus healthy control eyes.
Offset Pinhole (OP) Adaptive Optics scanning light ophthalmoscopy(AOSLO) imaging was performed on 5 subjects with DR (mean age 47, 35-61 years old) and 4 healthy controls (mean age 29, 25-37 years old). OP AOSLO used a 790 nm light source and a 1.5° field-of-view. Whenever used, AOSLO FA was performed using simultaneous reflectance (790 nm) and fluorescence (488 nm) image sequences with a 1.75° field-of-view after consumption of oral fluorescein. After sinusoidal distortion and eye motion correction, respective registered averages were stitched together to create structural (OP AOSLO) and perfusion (AOSLO FA) maps. Structural and perfusion maps were compared to identify the perfused capillaries surrounding the FAZ (Fig. 1). To ensure equal distribution of measurements, structural maps were divided into equiangular octants and segments 15° apart centered at the fovea. Lumen diameter measurements on perfused capillaries in OP AOSLO structural maps were then performed manually on 3 segments per octant.
Results are presented as mean diameters± SD, and statistical significance was assessed using a two-tail t-test with a p-value <0.05. DR eyes had statistically significant higher perifoveal perfused capillary lumen diameters than those of control eyes (5.5 ± 2.2 μm vs. 4.2 ± 0.89 μm; t(204) = 5.2, p < 0.0001). Also, DR eyes exhibited greater lumen diameter variability with a larger coefficient of variation compared to that of control eyes (0.34 vs. 0.24).
The ability to quantify changes to the FAZ capillary lumen diameter in subjects with DR may have clinical value for early detection of microvascular changes, enabling interventions prior to capillary decompensation.
This PDF is available to Subscribers Only