Abstract
Purpose :
To analyze the changes of foveal avascular zone (FAZ) and macular vasculature in type 2 diabetic patients without diabetic retinopathy using optical coherence tomography angiography (OCT-A).
Methods :
The prospective observational study was designed including 21 diabetic eyes (21 subjects) and age- and sex-matched 20 control eyes (20 subjects). In the 6x6mm OCT-A images of macula, we used imageJ software to measure the area/circularity of FAZ and vascular density (VD)/perfusion index (PI) in the superficial and deep capillary plexus (SCP and DCP) separately.
Results :
The area of FAZ revealed no significant difference between the diabetic and control eyes (SCP: 0.35 vs. 0.40, p=.31 and DCP: 0.69 vs. 0.69, p=.92). There was also no significant difference in the circularity of FAZ in both SCP (0.82 vs. 0.78; p=.16) and DCP (0.79 vs. 0.80; p=.76). Diabetic eyes showed significantly decreased VD (18.99 vs. 21.05 p=.031) and PI (0.30 vs. 0.33 p=.019) compared with control in SCP. In DCP, VD was significantly lower in diabetic eyes than control (24.06 vs. 24.85; p=.025), however PI showed no meaningful difference (0.38 vs. 0.41; p=.198). Duration of diabetes was negatively correlated with vessel densities of superficial (r=-0.47, p=.002) and deep (r=-0.41, p=.009) capillary layers.
Conclusions :
Even in the stage without diabetic retinopathy, the type 2 diabetic eye shows a decrease in the macular vasculature compared to the normal eye.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.