Abstract
Purpose :
Purpose: To investigate the size and shape of the foveal avascular zone (FAZ) which was determined by optical coherence tomography angiography (OCTA) and the relationship of the size and shape to the clinical findings in normal subjects.
Methods :
Methods: Seventy eyes of 70 healthy volunteers underwent OCTA of their eyes. The size of the superficial FAZ was assessed by its area, perimeter, and Feret’s diameter, and the shape by the circularity, aspect ratio, roundness, and solidity. The coefficients of variation (CV) of each parameter were calculated. The correlations between each parameter and the clinical findings were determined.
Results :
Results: The CV of the parameters of the size of the FAZ were higher than that of the parameters of the shape of the FAZ. The area, perimeter, and Feret’s diameter of the FAZ were significantly larger in women than in men (P<0.01 for each). The spherical equivalent was weakly but significantly correlated with Feret’s diameter (R=0.242 P=0.043). The axial length was significantly correlated with the area (R=-0.395, P<0.001), perimeter (R= -0.395, P=0.001), and Feret’s diameter (R= -0.424, P<0.001). The central macular thickness (CMT) was significantly correlated with all parameters (area, R=-0.756 P<0.001; perimeter, R=-0.704 P<0.001; Feret’s diameter, R=-0.708 P<0.001; circularity, R=-0.304 P=0.011; axial ratio, R=0.299 P=0.012; roundness, R=-0.272 P=0.022; and solidity, R=-0.380 P<0.001). Multiple linear regression analysis showed that the CMT was strongly correlated with all parameters
Conclusions :
Conclusions: Although the CMT was a critical factor that was significantly correlated with the size and shape characteristics of the FAZ in normal subjects, the shape might be a better factor for characterizing the FAZ than the size because of the low CV of the measures of the shape and the characteristics are less affected by the other ocular factors.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.