Hyaloid canal is a small transparent canal running through the vitreous body from the optical nerve disc to the lens

Lens (anatomy)

The crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a...

; in the fetus

Fetus

A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...

 it contains a prolongation of the central artery of the retina, the hyaloid artery

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...

. Other names: Cloquet's canal, Stilling's canal.

The function of the canal is to provide an adjustable reservoir of mobile liquid which may be easily and rapidly displaced backwards in positive accommodation, forwards in negative accommodation.