Analysis of foveal avascular zone by using spectral-domain optical coherence tomography angiography in healthy Indian eyes

Abstract

Purpose: To analyze FAZ superficial (s) and deep (d) area and dimensions by using spectral-domain optical coherence tomography angiography (OCTA) in healthy eyes and to assess effect of age, gender, axial length (AL), central foveal thickness (CFT), and central choroidal thickness (CCT) on FAZ. We aimed to study FAZ dimensions with OCTA in healthy Indian eyes with the purpose of creating a normative database.

Settings and design: Observational cross-sectional study.

Methods: In total, 200 healthy eyes in the age group of 20-60 years having best corrected visual acuity better than 6/12 (Snellen's) with no systemic illness/intraocular surgery were included. FAZ parameters were calculated using OCTA, and the same was evaluated for any correlation with different ocular parameters mentioned above. The data were reported as frequencies/percentages and mean ± SD. The association between quantitative variables was evaluated using Pearson's correlation coefficient.

Results: The dFAZ area (0.56 ± 0.12 mm 2 ) was larger than the sFAZ area (0.42 ± 0.13 mm 2 ). Females had larger FAZ than males. AL and CFT had a negative correlation, whereas CCT had a positive correlation with FAZ. Age did not influence FAZ. sFAZ and dFAZ varied significantly in healthy eyes.

Conclusion: FAZ parameters calculated using OCTA in healthy Indian eyes suggested that the area and dimensions in both SCP and DCP are larger in individuals from the Indian subcontinent when compared to other parts of the world. FAZ area and dimensions, when compared to previous studies, were variable. Thus, there is a need to establish normative data for ethnicity for proper interpretation of FAZ using OCTA.