Related Experiment Video
Updated: Feb 15, 2026

Doppler Optical Coherence Tomography of Retinal Circulation
Published on: September 18, 2012
Foveal Avascular Zone in Normal Tension Glaucoma Measured by Optical Coherence Tomography Angiography
Maja Zivkovic1,2, Volkan Dayanir3, Tolga Kocaturk4
1Medical Faculty, Department of Ophthalmology, University of Nis, Nis, Serbia.
Aim:
To measure diameter of foveal avascular zone (FAZ), FAZ area, and vessel density using Optical Coherence Tomography Angiography (OCT-A) in patients with normal tension glaucoma (NTG) and to establish the possible role of OCT-A in diagnosis and follow-up of patients with NTG.
Methods:
Twenty-one eyes of 21 patients with NTG and 30 eyes of 30 healthy subjects underwent complete ophthalmic examination as well as OCT-A on ZEISS AngioPlex. 3 × 3 macula scans were used to measure vertical, horizontal, and maximum diameter of FAZ by two graders. Mean values and interobserver variability were analyzed. Image J was used for analysis of FAZ area and vessel density.
Results:
Mean vertical diameter (t = 5.58, p < 0.001), horizontal diameter (t = 3.59, p < 0.001), maximum diameter (t = 5.94, p < 0.001), and FAZ area (t = 5.76, p < 0.001) were statistically significantly enlarged in the NTG group compared to those in the control group. Vessel density (t = -5.80, p < 0.001) was statistically significantly decreased in the NTG group compared to that in the control group.
Conclusion:
OCT-A could have an important role in the future in diagnosis of patients with NTG. In patients with NTG, there is larger FAZ area, while the vessel density is reduced in comparison to the control group.
More Related Videos
Related Concept Videos
Hybrid Zones
Tension
Surface Tension, Capillary Action, and Viscosity
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
Glaucoma: Overview
Zones of Protection
Protective zones are defined by closed dashed lines, containing one or more components. A key characteristic of these zones is the strategic placement of...
Transition Zone

