Foveal avascular zone

Foveal avascular zone (FAZ) is a region in the eye's retina where there are no blood vessels. It is located in the center of the macula, an area of the retina responsible for sharp, central vision. The FAZ is crucial for maintaining optimal visual acuity.

Anatomy

The FAZ is a circular area with a diameter of approximately 0.5 mm. It is located in the center of the macula, surrounded by the fovea, the area of the retina with the highest concentration of cone cells, which are responsible for color vision and fine detail. The absence of blood vessels in the FAZ allows for unobstructed passage of light to the photoreceptors, contributing to high-resolution vision.

Function

The primary function of the FAZ is to provide an unimpeded path for light to reach the photoreceptors. By lacking blood vessels, the FAZ ensures that there is no scattering or absorption of light before it reaches the photoreceptors. This is crucial for maintaining high visual acuity and sensitivity to detail.

Clinical significance

Changes in the size or shape of the FAZ can be indicative of various eye diseases, including diabetic retinopathy, macular degeneration, and retinal vein occlusion. These changes can be detected using imaging techniques such as optical coherence tomography (OCT) and fluorescein angiography.

In diabetic retinopathy, for example, the FAZ can become enlarged due to the death of retinal cells caused by high blood sugar levels. In macular degeneration, the FAZ may become distorted or irregular due to the growth of abnormal blood vessels under the retina.

See also

• Fovea centralis
• Macula of retina
• Retina
• Diabetic retinopathy
• Macular degeneration