Foveal Avascular Zone and Its Associations - An Analysis Using OCTA: Results From the Gutenberg Health Study

The aim of this study was to describe the distribution and ocular and systemic associations of the foveal avascular zone (FAZ) area in Caucasians in a population-based setting.

We included 1004 participants (aged 59.91 ± 9.39 years; 49.3% female) of the 10-year follow-up of the Gutenberg Health Study, a population-based, prospective cohort Study in Mainz, Germany, with gradable optical coherence tomography angiography of the macula. The FAZ area of the total retina was measured manually. Linear regression analysis was conducted to evaluate the associations of the FAZ area with ocular and systemic factors.

The mean FAZ area was 0.27 ± 0.12 mm2. It was associated with female sex (B-estimate 0.04; 95% confidence interval [CI], 0.03-0.06; P < 0.001) and inversely with axial length (B-estimate -0.02; 95% CI, -0.03 to -0.01; P < 0.001). Multivariable analysis of the FAZ area confirmed the associations with sex and axial length. No association was found with age, body mass index, blood pressure, diabetes, smoking, chronic kidney disease, socioeconomic status, or best-corrected visual acuity.

The FAZ area was larger in females and in participants with a shorter axial length indicating that both ocular and anthropometric factors may influence FAZ size.

This study provides normative data of the foveal avascular zone area in an adult Caucasian population and describes the ocular and systemic associations that have to be taken into account when interpreting optical coherence tomography angiography data in Caucasians.