Saturday, August 28, 2010

Trabecular Meshwork

The trabecular meshwork is an area of tissue lying around the base of the eye cornea, near the ciliary body. It is responsible for draining the aqueous humor from the eye via the anterior chamber (the chamber on the front of the eye covered by the cornea). The trabecular meshwork is spongy and lined by trabeculocytes, allowing fluid to drain into a set of tubes called Schlemm's canal flowing into the blood system.

The trabecular meshwork is made up of three parts: 1) inner uveal meshwork, which contains thin cord-like trabeculae, orientated predominantly in a radial fashion, enclosing trabeculae spaces larger than the corneoscleral meshwork; 2) corneoscleral meshwork, which contains a large amount of elastin, arranged as a series of thin, flat, perforated sheets arranged in a laminar pattern; 3) juxtacanalicular tissue, which lies immediately adjacent to Schlemm's canal, composed of connective tissue ground substance full of glycoaminoglycans and glycoproteins.

The trabecular meshwork is assisted to a small degree in the drainage of aqueous humour by a second outflow pathway, the uveo-scleral pathway (5-10% of outflow occurs this way). The uveo-scleral pathway is increased with the use of glaucoma drugs such as prostaglandins.