What is Glaucoma?

Glaucoma is a disease where the nerves in the eye die causing tunnel vision and in the worst case blindness. Early detection of glaucoma can lead to better control and less optic nerve damage so it is less likely to cause blindness.

Glaucoma is believed to be caused by the pressure of the fluid in the eye being higher than what the nerves in the eye can handle. Some people have higher pressures without showing signs of glaucoma, and other people have glaucoma with lower intra-ocular pressures.

The intra-ocular pressure is measured as part of a standard optometric exam in everyone over forty years of age. Visual field testing is performed when the intra-ocular pressures are high or if there are other reasons to suspect glaucoma. Visual field testing detects early signs of tunnel vision.

Diagnosing Glaucoma

Glaucoma can often be difficult to diagnose at the early stages. Tests for glaucoma include measurement of intra-ocular pressure, visual field testing, assessment of the optic nerves, and Optical Coherence Tomography.

In many cases, none of these tests gives a definite result at the early stages of glaucoma. Often worsening of the optic nerve appearance or of the visual fields needs to be documented to prove the existence of glaucoma. Ophthalmologists are unlikely to start treatment if there is any doubt about whether glaucoma is present. It is common for people who are being investigated for glaucoma to be reviewed every few months to try to show if there is glaucoma, or if there is no damage occuring.

Once it is shown that optic nerve damage has occured or that the visual fields have a defect, then treatment is commenced by the ophthalmologist. Treatment consists mainly of reducing the pressure in the eyes to stop damage to the optic nerves.

The main form of treatment is with eye drops to reduce the pressure. The eye drops only work whilst they are being used, so the treatment is required for the rest of the patient’s life. This is why ophthalmologists will not start treatment unless it is proven to be necessary. If drops do not work to reduce the presssure then surgery or laser surgery can be performed by an ophthalmologist who specialises in glaucoma.

For further information, please visit Glaucoma Australia