Obese Foveal Avascular Zone Assessed by Optical Coherence Tomography Angiography of the Retina: Is There a Relation to Comorbities?

Abstract

Purpose: To investigate the foveal avascular zone (FAZ) in obese by optical coherence tomography angiography (OCT-A) and to evaluate the findings of structural optical coherence tomography (OCT) and their relations with comorbidities. Methods: It was included 35 obese (study group) and 30 normal individuals (control group). Patients with retinal diseases and retinal treatments were excluded. The images were obtained using the Topcon ® . Results: The mean areas of FAZ in superficial plexus (FAZ-SP) and deep plexus (FAZ-DP) were significantly greater in the study group: FAZ-SP was 405.0 ± 136.4 µm 2 in the obese group and 307.3 ± 78.6 µm 2 in the control group and in the left eye (LE) 477.1 ± 124.4 µm 2 in the obese group and 384.0 ± 88.7 µm 2 in the control group. This difference was statistically significant (RE: p = 0.0014 and LE: p = 0.0012). The mean area of the FAZ-DP was 491.0 ± 124.4 µm 2 (Right eye-RE) in the obese group and 384.4 ± 88.7 µm 2 in the control group and in the left eye (LE) was 497.9 ± 124.1 µm 2 in the obese group and 484.9 ± 92.7 µm 2 in the control group. There were no correlations regarding FAZ-SP and FAZ-DP in both eyes with fasting blood glucose, glycated hemoglobin, total cholesterol and fractions and triglycerides. A significant association between enlargement of FAZ-DP and type 2 diabetes mellitus (p = 0.0160) was observed. Conclusion: The FAZ areas in superficial and deep plexus achieved significantly greater values in the study group. There was a significant association between a larger deep FAZ area and type 2 diabetes mellitus. It is necessary an evaluation with a larger sample size to corroborate the findings.

Investigation of factors that may affect the foveal avascular zone: An optical coherence tomography angiography study

“…To date, very little research has been carried out, investigating the relationship between the foveal avascular zone area and overweight/obesity. One study, involving a smaller cohort (n = 35 obese, n = 30 control subjects), reported a significantly larger foveal avascular zone area in the superficial and deep plexus in obese subjects (>30 kg/m 2 ) 24 . Furthermore, a significant association between a larger foveal avascular zone area in the deep plexus and type 2 diabetes was observed 24 .…”

“…One study, involving a smaller cohort (n = 35 obese, n = 30 control subjects), reported a significantly larger foveal avascular zone area in the superficial and deep plexus in obese subjects (>30 kg/m 2 ) 24 . Furthermore, a significant association between a larger foveal avascular zone area in the deep plexus and type 2 diabetes was observed 24 . Overweight/obesity is considered an important factor in the etiology of type 2 diabetes 25 .…”

“…24 Furthermore, a significant association between a larger foveal avascular zone area in the deep plexus and type 2 diabetes was observed. 24 Overweight/obesity is considered an important factor in the etiology of type 2 diabetes. 25 Changes in lipid metabolism, low blood flow, oxidative stress, and inflammation, all associated with overweight/ obesity and diabetes, can result in capillary dropout and damage to the retinal vasculature.…”

Investigation of Factors Associated with Retinal Oxidative Stress and Inflammation that affect the Foveal Avascular Zone in Healthy Eyes: An Optical Coherence Tomography Angiography Study

“…Reduced vessel density and perfusion, lower CMT and high BMI/ trunk fat % are all associated with in ammatory conditions and with a larger FAZ area. [21], [52], [64], [66], [67] In ammation is associated with oxidative stress, which can cause retinal damage over time. Furthermore, in the current study, larger FAZ area was associated with lower MP status and, therefore, antioxidant status in a young, healthy population.…”

“…However, one small study, (n = 65) found a larger FAZ area in obese subjects. [52] Obesity is associated with oxidative stress, which in turn; is linked with capillary dropout and damage to the retinal vasculature. [53] Overweight/obesity is also considered an important factor in the aetiology of Type 2 diabetes.…”