The<unk>  pierces the eyeball close to the optic nerve, sending branches over the internal surface of the<unk>  and these terminal branches are the only blood supply to the larger part of it. The<unk>  part of the<unk> where the light rays are focused after passing through the pupil and the lens is a circular area called the macula. The center of this circular area is the fovea. The fovea and a small area surrounding it are not supplied by the<unk>  or its branches, but instead by the choroid. The<unk>  is approximately 160 micrometres in diameter. Variation In some cases - approximately 20% of the population - there is a branch of the ciliary circulation called the cilio-retinal artery which supplies the<unk> between the macula and the optic nerve, including the nerve fibers from the foveal photoreceptors. If this artery is present, the<unk>  vision will be preserved even in case of<unk>  occlusion <unk> O). Development The<unk>  is formed from the proximal part of the hyaloid artery after atrophy of its distal part has formed the hyaloid canal.
Central retinal artery
Ophthalmic artery
Internal carotid artery
Pontine arteries
Trigeminal artery
Lacrimal groove
Oculomotor nerve
Lacrimal sac