Dimensions of the foveal avascular zone using the Heidelberg retinal angiogram-2 in normal eyes

Abstract

Purpose:The purpose was to study the dimensions of the foveal avascular zone (FAZ) using Heidelberg Retinal Angiogram-2 (HRA-2; Heidelberg Engineering GmBH, Dossenheim, Germany).Materials and Methods:An observational study of the FAZ area and circumference was done with fundus fluorescein angiography (FFA) using HRA-2 in 31 normal individuals. The FAZ was studied using both contrast-adjusted and nonadjusted methods. Contrast adjustment was done to obtain better visualization of the finer capillaries around the fovea enabling more precise measurements of the FAZ in normal eyes.Results:The mean area of the FAZ calculated by the contrast-adjusted method was 0.2753 mm2 (±0.074) and the mean circumference was 2.22 mm (±0.048). By the conventional method, the area and circumference of the FAZ were 0.6241 mm2 (±0.177) and 3.23 mm (±0.454), respectively.Conclusion:The measurements of area and circumference of FAZ using contrast-adjusted methods were significantly smaller than the conventional method.

Reproducibility and repeatability of foveal avascular zone measurements in healthy subjects by optical coherence tomography angiography

“…Recently, John et al 18 hypothesised that the use of the contrast-adjusted method could be a better tool for studying digital angiogram pictures. They found that the FAZ area outlined by the conventional method was larger than by the contrast-adjusted method (0.6241±0.177 mm 2 vs 0.2753±0.074 mm 2 , respectively).…”

Normative Data for Vascular Density in Superficial and Deep Capillary Plexuses of Healthy Adults Assessed by Optical Coherence Tomography Angiography

“…Its size as measured by fluorescein angiography reflects the status of the microcapillary circulation in the foveal area. [29][30][31][32] Also, the FAZ area has a strong positive correlation with the degree of capillary nonperfusion in diabetic retinopathies. 33,34 We observed that the FAZ area was larger (P < 0.001) in the DCP than in the SCP.…”

Measurement of Foveal Avascular Zone Dimensions and its Reliability in Healthy Eyes Using Optical Coherence Tomography Angiography

“…Various methods including histology, immunohistochemistry, fluorescein angiography (FA), and indocyanine green angiography (ICGA) have been used to evaluate the retinal vasculature 1 . Such in vivo and in vitro assessments show variations in the dimensions of the FAZ in normal eyes 2,3 . An accurate and reliable method of measuring FAZ dimensions could serve an important role in the diagnosis and management of various retinal vascular diseases that affect the FAZ, such as diabetic retinopathy or retinal vein occlusions.…”