Hyaloid canal (Cloquet's canal and Stilling's canal) is a small transparent canal running through the

vitreous body The vitreous body (''vitreous'' meaning "glass-like"; , ) is the clear gel that fills the space between the lens and the retina of the eyeball (the vitreous chamber) in humans and other vertebrates. It is often referred to as the vitreous humor ...

from the

optic nerve In neuroanatomy, the optic nerve, also known as the second cranial nerve, cranial nerve II, or simply CN II, is a paired cranial nerve that transmits visual system, visual information from the retina to the brain. In humans, the optic nerve i ...

disc to the

lens A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ...

. It is formed by an invagination of the

hyaloid membrane The vitreous membrane (or hyaloid membrane or vitreous cortex) is a layer of collagen separating the vitreous humour from the rest of the eye. At least two parts have been identified anatomically. The posterior hyaloid membrane separates the rear ...

, which encloses the vitreous body. In the

fetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal deve ...

, the hyaloid canal contains a prolongation of the

central artery of the retina The central retinal artery (retinal artery) branches off the ophthalmic artery, running inferior to the optic nerve within its dural sheath to the eyeball. Structure The central retinal artery pierces the eyeball close to the optic nerve, sendin ...

, the

hyaloid artery The hyaloid artery is a branch of the ophthalmic artery, which is itself a branch of the internal carotid artery. It is contained within the optic stalk of the eye and extends from the optic disc through the vitreous humor to the lens. Usually f ...

, which supplies blood to the developing lens. Once the lens is fully developed the hyaloid artery retracts and the hyaloid canal contains

lymph Lymph (from Latin, , meaning "water") is the fluid that flows through the lymphatic system, a system composed of lymph vessels (channels) and intervening lymph nodes whose function, like the venous system, is to return fluid from the tissues to ...

. The hyaloid canal appears to have no function in the adult eye, though its remnant structure can be seen. Contrary to initial belief, the hyaloid canal does not facilitate changes in the volume of the lens. The lens volume changes by less than 1% over its range of accommodation. Furthermore, lymph, being liquid, is incompressible, so even if the volume of the lens did change, the hyaloid canal could not compensate for it.

References

{{Authority control Human eye anatomy de:Arteria hyaloidea

See also

References