What is Glaucoma
Glaucoma is a group of eye diseases where the optic nerve, which connects the eye to your brain, is damaged due to the pressure of the fluid inside your eye.This may be because the pressure is higher than normal, or because the nerve is more susceptible to the damage from the pressure. This can affect one or both eyes. There are two main types of Glaucoma: Chronic Glaucoma, which happens slowly and gradually and Acute Glaucoma which comes on suddenly. Chronic Glaucoma is much more common than acute glaucoma.
Who is at risk?
Anyone can develop chronic glaucoma the risk increases if you:
Are ages over 40
Are very short-sighted
Are of African or Caribbean origin
Are closely genetically related to someone with chronic glaucoma (Parents or siblings)
If you are 40 or over The NHS will fund an NHS Test or you. If you have raised pressure within your eye. This is called Ocular HyperTension (OHT)
How can chronic glaucoma be detected?
The early stages of chronic glaucoma do not manifest symptoms. The best way to detect glaucoma early is to have regular eye examinations, so the condition can be managed.
A glaucoma patient may observe a reduced blurred field of vision. This is when the condition is established and the sensitive nerve endings in the back of the eye have lost their sensitivity. To avoid, ensure you book a regular Eye Examination and Sight Test. Ring 01704831117 to book an appointment.
Some people buy “Off the shelf” Ready Made magnifiers, which they refer to as “Reading Glasses”. They are not prescribed glasses to an accurate prescription, which makes allowances for the individual prescription in each eye and the optical alignment of the lenses to your eyes. This in itself is not harmful to an adults eye, although it will not correct your vision accurately and give the best comfort. The main course for our concern is that you bypass the vital role of the Eye Examination and health check when you pick up a pair of magnifiers from the garage or sweetshop. You could still do this if you elect to, but ensure a regular test.
There are three main procedures to evaluate if you have chronic glaucoma.
The first one is where we look at the Optic Nerve at the back of the eye with an ophthalmoscope, it looks like a handheld torch or a slit lamp, which is a type of illuminated microscope. The light shines into your eye so we can see through your pupil to the back of your eye. We may also take a photograph or a scan of the Optic Nerve. This can be useful for future visits. We can build up an ocular history of the vital parts at the back of your eye, so we can store the images to make future comparisons and monitor any changes.
The second test is where we measure the pressure inside your eye. This may be conducted by using a non-contact tonometer which doesn’t make contact with your eye, but gently blows a puff of air on your eye. Or by giving you an aesthetic eye drop which desensitises the eye so we can gently be pressing an instrument called a tonometer against the cornea. The test is comfortable and painless and only lasts moments.
The third test is where we measure how extensive field of vision is – how far you can see around you when you are looking straight ahead. Sometimes you can have chronic glaucoma even if you have normal pressure, which is why we perform all of these tests and on occasions repeat them on a different day if needs be.
Some people have raised interocular pressure but they do not have Glaucoma. Some people naturally have pressure that is above the “normal range”. This is just a physiological anomaly. The pressure does not cause any damage to their eyes.
This means that they do not have glaucoma. However, they are more likely to develop chronic glaucoma, so will advise you how often you should return to have this monitored.
How can chronic glaucoma be treated
If we suspect that you may have glaucoma, you will be referred to you to an Ophthalmologist. If you have chronic glaucoma, you may be given eye drops to use every day, or you may require surgical intervention. The drops will reduce the pressure and help control the build-up of any fluid. It is paramount that you take them and ensure that they go into your eye properly. Poor compliance will reduce your chance of halting the condition.
You will not feel different in any way, so you will not be able to tell that the treatment is working. This is why it is very important to go to your follow-up appointments and keep on using the drops.
If you find it hard to use the eye drops, call into the practice and tell us about it. We can help you with techniques or advise on special bottles or holders to make inserting the drops easier. Currently, there isn’t a cure for chronic glaucoma but it can be treated very effectively, generally with eye drops. Any pre-treatment eye damage will probably be permanent, but your sight could get much worse if you stop the treatment. It is vital that you use the eye drops every day, even if you don’t think that they are helping.
Driving when diagnosed with Glaucoma
If you drive and you have been diagnosed with glaucoma in both eyes, then this will reduce your field of vision. It is not just about what your visual acuity is. i.e. The lowest line on the chart you can read when corrected with a spectacle prescription. The issue is how far to the right/left up and down can you see when looking straight ahead. This is called your visual field. The law says that you must tell the DVLA (Driver and Vehicle Licensing Authority). The DVLA may require you to take another Visual Field test which satisfies their specific fitness to drive criteria tests. Many people are given an extended licence to allow them to continue to drive for a further period before being recalled to be monitored again.
Some people have to have their driving licence revoked because they could become a danger to themselves and others. In our experience, many patients initially resent this and are in denial of the reality of the facts. They soon accept a change in lifestyle and recognise that taxis and public transport works out less than running a car and often family and friends will support them where they can.
Acute Glaucoma is where the drainage system in your eye is blocked in some way. This causes the pressure inside your eye to increase rapidly. It can be caused due to trauma to the eye or head. Regular Eye Examinations are key to maintaining and monitoring
Good Eye Health
Do not neglect your Eye Care. Even if you do not wear glasses or feel you do not have any visual problems book in for a comprehensive Eye Examination and Sight Test. Even if you use magnifiers it is important not to bypass the Test especially if you are 40 or over and not been tested before.
In some cases increased interocular pressure can drop and spike and some people get short moments of pain and/or discomfort coupled with blurred vision. This sometimes happens when your pupils (dilate) get bigger, at night or when you are in a dark area (like the theatre ) or if you are reading.
Some other symptoms are aches in your eye which are transient, red eyes, or seeing coloured rings around white lights, or some describe it’s looking through a haze or mist. If you get any symptoms it is important to act quickly, even if your symptoms go away. Your vision may be damaged each time the symptoms occur. Do not ignore it. If you have these symptoms but they have gone away you should book an appointment with us, as soon as possible, explaining your specific symptoms.
If you have constant symptoms that have not subsided you should go to the accident and emergency department immediately so that the pain and the pressure in the eye can be relieved and continued damage to your eye can be halted. You may think this laughable, but over the many years we have been in practice we had people say the reason they didn’t go immediately to the hospital was because they were going to the hairdressers! Or they had to walk the dog! It’s astonishing that such tasks take priority over saving your own sight from deteriorating.
Who is at risk?
People who are more likely to get acute glaucoma are if you are over the age of 40, female people of East Asian or South Asian origin, people with a family history of closed-angle glaucoma or people who are long-sighted.
For more information on Glaucoma, look up glaucoma on the NHS choices website www.nhs.uk or phone sightline on 01233 648170 or visit www.glaucoma-association.com
For more information, ring us on 01704 831117 or call into the Practice