Glaucoma is a condition of the optic nerve, the nerve at the back of your eye that sends
your vision to your brain. Traditionally, we always thought of glaucoma as a high-pressure,
the pressure in the eye being too high and that damaging the optic nerve and causing
you to lose your sight. We’ve recently learned that although pressure plays a role, it doesn't
necessarily have to be high out of the abnormal range to cause the damage. It’s just too
high for your eye and we need to lower the pressure and we know that lowering the pressure
lowers the risk of you developing glaucoma so it’s very important that you get the
pressure checked and make sure your eyes nerves stays healthy.
Glaucoma is caused by many factors some of them are unknown. The biggest factor for glaucoma
is the pressure in the eye, the intra ocular pressure. That is the one single factor that
we can try to treat and control and that's how we manage glaucoma by keeping the pressure
down. There is a genetic component to glaucoma so if you have a family history of glaucoma,
you’re much more likely to develop the disease and certain people with certain conditions
within the eye or generally such as diabetic or short-sighted people are more likely to
get glaucoma.
We diagnose glaucoma traditionally with the
three important items that we need to look at. The first being the intraocular pressure,
we’re going to look at the pressure within the eye and make sure that’s normal. If
it's high then that increases your risk of developing glaucoma. The second thing we look
at is the visual field, looking at the peripheral visual field of vision, and traditionally,
that test is done on each individual eye separately and it maps out your field of vision and tells
us if there’s anything going on that needs treatment.
Normally, glaucoma affects your peripheral vision before it affects your central vision
so we need to test the peripheral vision. Then most importantly, we need to look at
the optic nerve at the back of your eye in detail. The optic nerve gets damaged from
the pressure will make it thinner and you lose nerve axon fibers. We need to detect
that and treat it and stop it from getting any worse.
We have scanners now that can scan your nerve and look at the invisible layers and tell
us exactly what is going on with the optic nerve and before we can even see a thing,
the scanner will pick it up and tell us your risks and it will actually look at your nerve
and compare it to a healthy individual of the same age. We also have measurements of
the wall of the eye to make sure that your wall isn’t thin which is an independent
risk factor for glaucoma and we have little tools that we use nowadays to look within
the eye looking at the drainage system so we can accurately assess that and look and
see whether there was any blockage going on for example.
Broadly speaking, there are three different categories of treatment for glaucoma. One
is the eye drops. The eye drops work very well but they do rely on the patient having
to put them in everyday. They can give you local and systemic side effects so we do watch
out for those and they can also stop working from time to time and occasionally, we need
to use combination eye drops to get the pressure down because all of these medications work
in slightly different ways either by increasing our drainage or decreasing the amount of fluid
the eye makes. The second is lasers. The lasers have been around quite a while but nowadays
the newer generation of lasers are very effective and very, very safe and are painless and quick.
Some of my patients will be very suitable for laser treatment to lower the pressure.
Some of these lasers work by removing the cells that make the fluid in the eye and then
some of these lasers work by increasing the drainage system the space within the eye to
allow the fluid to drain better and keep your pressure down. And these are nowadays outpatient
procedures with no downtime for the patient. Thirdly, is surgery. Surgery is very effective but it
is invasive. The gold standard trabeculectomy operation works very well and is still one
of the go-to procedures when we really need to get the pressure down and save someone's
sight. There are newer techniques which work just
as well nowadays which are less invasive and quicker and obviously kinder to the eye as
well. For example, I can do a trabeculectomy in about 20-30 minutes, but I can do the same
thing with the newer microtube XEN procedures which do exactly the same in under 5 minutes
with no major cut or stitches to the eye. There are lots and lots of new surgical techniques
on the market now and we’re evaluating them all and looking at what is suitable for each
individual person.