Vitreous body
Corpus vitreum
Definition
The vitreous body (vitreous humour) is a transparent, gel-like substance that occupies the vitreous (or postremal) chamber within the posterior segment of the eyeball. It lies between the posterior surface of the lens anteriorly and the retina posteriorly, and constitutes approximately four-fifths of the volume of the eye.
The vitreous body is composed mainly of water, together with collagen fibres and hyaluronic acid, which together maintain its gel-like consistency and transparency. It is enclosed externally by a thin layer called the hyaloid membrane (a.k.a. the vitreous membrane or vitreous cortex).
Functional correlates
Functionally, the vitreous body helps maintain the spherical shape of the eyeball, supports the retina against the choroid, absorbs mechanical shock, and permits the transmission of light to the retina with minimal scattering. Anteriorly, it is related to the posterior lens capsule through Wiegers ligament, while posteriorly it is closely applied to the internal surface of the retina.
References
Standring, S. (Ed.). (2015). Eye (Chapter 42). In Gray's anatomy: The anatomical basis of clinical practice (41st ed., pp. ). Churchill Livingstone.
