Foveal avascular zone

Within the fovea is a region devoid of retinal vessels known as the foveal avascular zone (FAZ). The geometric centre of the FAZ is often taken to be the centre of the macula and thus the point of fixation. It is an important landmark in Fluorescein angiography. It's diameter is 0.5mm (the central 1.5 degrees of an individual's Visual field.

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