Abstract
Purpose :
To evaluate the clinical implications of periarteral capillary free zone (paCFZ) in normal retina measured by optical coherence tomography angiography (OCTA) and compare its’ association with severe non-proliferative diabetic retinopathy (NPDR).
Methods :
Spectral-domain OCTA was acquired with a Cirrus prototype. Two independent graders measured the diameter and area of paCFZ and adjacent large artery in each peripapillary quadrant in a concentric circles (half to one disc diameter from the optic disc margin). A total of 148 normal subjects (148 eyes)and 115 patients (115 eyes) with severe NPDR were recruited in this study.
Results :
The maximum width of paCFZ in the inferior temporal quadrant (168.53±19.32um) was smaller than the other three quadrants (Ps=0.00). The area of paCFZ in the superior quadrant was significantly larger than in the inferior quadrant (P<0.05). The ratio of maximum width and area of paCFZ to artery inner caliber was much larger in the nasal quadrant than in the temporal quadrant (P<0.05). In patients with severe NPDR, the maximum width and area of paCFZ became significant larger, and the retinal artery inner diameters became significant smaller in each quadrant than normal subjects (Ps <0.05). The ratio of maximum width and area of paCFZ to adjacent inner artery became significant greater than normal subjects (Ps<0.05).
Conclusions :
OCTA provides an ability to noninvasively and quantitatively assess paCFZ. The maximum width and area of paCFZ, and their ratio to adjacent inner artery width and areaare correlated with severe NPDR.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.