WHAT IS GLAUCOMA
The proper definition of glaucoma is a characterised visual field defect caused by damage to the nerves at the back of the eye.
Glaucoma is often mis-defined as high pressure of the eye. High, or raised, intra-ocular pressure (IOP) is a risk factor for glaucoma and is often one of the earliest signs of the condition, though the presence of high IOP does not necessarily mean that there is glaucoma.
Glaucoma usually affects both eyes, though one eye may develop it sooner and quicker than the other. Most cases of glaucoma occur due to an increase of pressure in the eye, which can then ultimately damage the optic nerve (which connects the eye to the brain).
As our understanding of the condition improves, and as the technology that allows us to detect it improves, we are able to find glaucoma at earlier stages than ever before. This is of great benefit when it comes to treatment.
WILL I NOTICE?
It is unlikely that you will notice any signs of glaucoma yourself, unless it has been present and untreated for many years, or unless you have a more rapid type of glaucoma. Glaucoma affects your peripheral vision and so you will not notice that your vision is getting worse in the early stages of glaucoma. This emphasises the importance of regular eye examinations, and the benefits of using the latest technology with each visit, as your optometrist will be able to pick up any signs before you know about it yourself.
HOW CAN GLAUCOMA BE DETECTED?
Your optometrist will check the appearance of the optic nerve at every eye examination and will check the pressure in your eyes using one of a few techniques. In addition every eye examination includes retinal photographs and OCT scans as standard, alongside Optomap imaging. This allows a far more detailed assessment of the structure of the nerve and therefore earlier detection of changes or irregularities.
Visual fields testing (peripheral vision tests) are also available when your optometrist feels this is required.
OCULAR HYPERTENSION
It is possible to have a raised eye pressure and not have glaucoma. It is however a risk-factor for glaucoma, and one that may require the same treatment as glaucoma.
WHAT TREATMENT IS ABAILABLE?
Initial treatment for glaucoma usually involves being prescribed eye-drops to try and gradually lower the pressure. If the pressure is very high then it may be decided that it is better to undergo surgery. Nowadays a different initial option is some laser treatment called SLT (Selective Laser Trabeculoplasty). This is a quick, safe and non-invasive treatment that helps improve the drainage of the fluid within the eye and therefore lower the pressure.
If the above treatments do not have the desired effect then other surgical procedures become an option.
Whatever the course of treatment it should be known that the treatment will not repair any existing damage. The treatment is given to hopefully slow down any further progression of the condition or to ideally stop it progressing completely
HOW OFTEN SHOULD I GET MY EYES TESTED?
A routine, standard eye examination should take place every 2 years at most. This will allow any changes to the pressure or optic nerve to be detected and any necessary action to be taken.
However, if there is an immediate family history of glaucoma (parent, sibling or child) then it may be advised to have the tests done on a more regular basis.