Abstract
Purpose :
It has been reported that foveal avascular zone (FAZ) could be enlarged during the progression of diabetic retinopathy. Our purpose in this study was to evaluate the retinal capillary dropout of macular area excepting FAZ enlargement in patients with diabetic retinopathy using optical coherence tomography angiography (OCTA).
Methods :
This retrospective case control study included diabetic patients (18 NDR eyes, 19 NPDR eyes, 4 PDR eyes) and 28 healthy control subjects who underwent OCTA examination (RTVue XR Avanti: Optovue Inc, Fremont, California, USA). Retinal capillary densities of the whole 3x3 mm area as well as four divided areas (superior, inferior, lateral, nasal) excepting FAZ area were measured in 3x3 mm OCT angioflow images centered on the fovea using NI Vision Builder (National Instruments, Texas, USA).
Results :
Retinal capillary densities of the whole 3x3 mm superficial OCTA images in healthy control, NDR, NPDR and PDR eyes were 45.6%, 39.7%, 37.7% and 34.2%, respectively. These of deep OCTA images were 59.7%, 51.6%, 42.8% and 34.2%, respectively. Retinal capillary densities of superficial as well as deep OCTA image in diabetic eye was significantly lower than these of healthy eyes (p<0.05, p<0.01, respectively). In superficial and deep OCTA images, there were no significant differences among the four areas (superior, inferior, lateral, nasal) in healthy, NDR, NPDR, and PDR eyes, respectively.
Conclusions :
Retinal capillary dropout could be caused independently of FAZ enlargement and spatially evenly in the macular area of diabetic eyes.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.