Summary

The optic nerve carries information from our eye to our brain. The amount of fluid and jelly matter in our eye determines the pressure. Fluid is constantly produced inside the eye and if it's outflow is restricted, the pressure inside the eye will increase and it can damage the optic nerve (Glaucoma).

Detailed Explanation

Glaucoma is characterised by elevated intraocular pressure associated with optic cupping and visual field loss. In the majority of cases, there is no associated ocular disease (primary glaucoma).

Glaucoma is the leading cause of preventable blindness in Australia.

The mechanism of raised intraocular pressure in glaucoma is impaired outflow of aqueous resulting from abnormalities within the drainage system of the anterior chamber angle (open-angle glaucoma) or impaired access of aqueous to the drainage system (closed-angle glaucoma). Treatment is directed toward reducing the intraocular pressure and, when possible, correcting the underlying pathogenis.

Reducing aqueous production is a method of reducing intraocular pressure. Several medications/eye drops reduce aqueous production. Surgical procedures that reduce production are available but are generally used only after medical treatment has failed.

The most common surgical procedure performed is a trabeculectomy. This surgery creates a bypass to the normal drainage mechanism, allowing direct access of aqueous from the anterior chamber to the subconjunctival or orbital tissues.

The surgery is generally performed under a local anaesthetic block and the patient is given relaxing drugs.