11 January 2022
What is glaucoma?
January is Glaucoma Awareness Month so we are taking the opportunity to discuss all things glaucoma and to share more about the condition. Glaucoma begins with a problem with your eye’s drainage. Without working drainage, the fluid and pressure in your eye begins to build up, in turn damaging the optic nerve. The optic nerve is the part of your eye which transmits visual signals from your retina to your brain, allowing you to see. When the optic nerve is damaged and doesn’t function properly, your vision becomes impaired and, if left untreated for a long period, it can cause permanent loss of vision. In fact, glaucoma is the second most common cause of blindness worldwide, following cataracts. The condition is most common in people aged 70+.
Up to 5% of people aged over 40 in the UK have high intraocular pressure (eye pressure) which, if left untreated, can be a major risk factor for developing glaucoma. There are different types of glaucoma, the most common of which is called open-angle glaucoma. This occurs when small deposits build up in your eye’s drainage passages, gradually becoming blocked over subsequent months or years.
Another type of glaucoma is closed-angle glaucoma. This occurs very suddenly and develops as a result of the angle between your iris and cornea being too narrow. Again, this leads to your drainage canals becoming blocked, raising your intraocular eye pressure. The third type of glaucoma is normal-tension glaucoma which doesn’t always have an obvious cause. There can be optic nerve damage similar to that which you would see in a case of glaucoma, even if the patient has normal eye pressure.
10% of glaucoma patients end up with some degree of visual impairment and, more worryingly, 5% of glaucoma cases result in the patient being blind.
What is at risk of developing glaucoma?
Glaucoma is primarily caused by high blood pressure which is linked to lots of different factors such as diet, exercise and genetics. Glaucoma is often hereditary so if you’re from a family in which people suffer with glaucoma, it’s advisable to get checked regularly for any changes to your optic nerve. Diabetic patients are twice as likely to develop glaucoma so this is another risk factor to take into account when assessing your probability of developing glaucoma.
If you are long-sighted (hyperopic), you are actually at a greater risk of developing closed angle glaucoma, where the angle between your iris and cornea is too narrow. Contrastingly, if you are short-sighted (myopic), your chance of developing open angle glaucoma is greater. Your risk factor for glaucoma also increases with age, with the NHS stating that adults in their 70s and 80s suffer with it most commonly.
There has also been research into the link between ethnicity and likelihood of developing glaucoma and it has been found that African Americans and Latinos are much more likely to get glaucoma than other races. These groups typically also suffer with glaucoma symptoms earlier than other ethnic groups do. Asian and Inuit populations have also been seen to be more at risk of developing closed angle glaucoma.
What are the symptoms of glaucoma?
Glaucoma nearly always occurs in both eyes. If you don’t regularly attend eye tests during which they assess your eye pressure, your glaucoma might not be detected until you notice some vision loss. Glaucoma first affects your peripheral vision but, if you’re only seeking treatment at this point, any vision already lost cannot be restored.
Closed-angle glaucoma, which comes on very quickly, can arrive with the following symptoms:
- Blurry vision
- Severe eye pain
- Halos appearing around lights
- Red eyes
- Light sensitivity
If you experience the above symptoms, you should seek medical assistance as soon as possible.
You should attend an eye test every two years in order to ensure that changes to the optic nerve are picked up before your vision has deteriorated beyond repair. Glaucoma is often diagnosed at a routine eye test before many patients even realise that they have the condition.
How can you treat glaucoma?
Before glaucoma can be treated, a range of examinations need to be performed to provide an accurate diagnosis. You can expect to have your pupils dilated to allow the optometrist to examine the back of your eye, including the optic nerve. There will also be an examination called a gonioscopy whereby the angle between your iris and cornea are checked, in order to ensure fluid can pass between them. You will also have your eye pressure measured to make sure it isn’t raised, as well as a visual field test to check your peripheral vision hasn’t been affected. Deteriorating peripheral vision is an indicator of glaucoma.
There are a number of treatment options available for patients who have been diagnosed with glaucoma. Although the treatments can slow the progression of visual damage, any vision which has already been lost can’t be restored. If your ophthalmologist recommends it, you could have surgery to reduce your eye pressure, preventing further damage to your optic nerve. There is also a type of laser treatment (different to the refractive laser eye surgery we offer at Optimax) which helps the aqueous fluid drain from the eye. There are two types of laser treatment for glaucoma; trabeculoplasty for open angle glaucoma, and iridotomy for closed angle glaucoma.
For a non-surgical approach, there are also a number of eye drops which can increase the drainage in your eye, thereby decreasing pressure built up by too much fluid. The type of treatment you are recommended will depend on which type of glaucoma you have and how advanced the condition is. The main takeaway from this blog post is simply to attend regular eye tests in order for you to monitor your eye health properly. With glaucoma, you require treatment before any vision has been lost, so don’t delay your next eye test!