12-18 June: National Glaucoma Awareness Week

Glaucoma has often been referred to as ‘the silent thief of sight’ as it can be a painless condition without symptoms until it has reached an advanced stage.

Glaucoma refers to a group of conditions that can cause damage to the optic nerve at the point in which it leaves the eye^1^. In the main, the damage occurs due to a build up of pressure,  caused by poor drainage of fluids at the front of the eye.

It is important that there is a normal pressure within the eye. The anterior segment (Image 1) is the space behind the cornea where clear fluids enter and leave continually. In this example, there is an ‘open angle’ where the cornea and iris (coloured part of eye) meet, and it is through this angle that the fluid leaves and drains. If the fluid drains slowly the pressure can begin to rise to a level that can cause damage to the optic nerve^2^. The optic nerve is responsible for carrying visual information from the eye to the brain, so damage here can lead to defective vision, and sadly, any vision that is lost to glaucoma cannot be recovered.

There are several different types of glaucoma:

• Chronic open angle glaucoma
• Acute closed angle glaucoma
• Secondary glaucoma
• Normal tension glaucoma

To read more about each type click here.

Even though glaucoma can affect children and teenagers, this is considered to be uncommon. According to the International Glaucoma Association (IGA), an estimation of more than 600,000 people suffer from glaucoma in the UK. But due to the lack of symptoms in the early stages, there could be many more people that are as yet undiagnosed^3^.

Who is most at risk?

• Older population

Chronic open angle glaucoma becomes more common as the eye ages and therefore is the most common form of glaucoma^4^.

• Family history

According to the IGA, there is at least a 4 times increased risk if you are a close/immediate relative of someone diagnosed with glaucoma i.e. father, mother, brother or sister^4^.

• Ethnicity

The different types of glaucoma can affect different ethnic groups around the world. For example, open angle glaucoma tends to affect more African/Caribbean people and unfortunately at a younger age too. Whereas, people of Asian origin tend to be at more risk of developing closed angle glaucoma^4^. 

It is vitally important that people over 40 and those that are in a higher risk factor group have a regular sight test with their Optometrist. As well as vision and other health checks being tested, the eye pressure and visual fields are measured. The Optometrist would also examine the head of the optic nerve very carefully and if they are concerned, they will refer you to a hospital appointment via your GP.  

In the UK, anyone over the age of 40 who is a direct family member of someone with glaucoma qualifies for a free NHS sight test. 

If diagnosed with glaucoma, one of the main treatments will be to use specific eye drops. If drops are prescribed, it is very important that these are administered correctly and at the required times. 

Here are some hints and tips of applying drops into the eye:

• Always make sure hands are washed and dry before applying drops
• Either sitting or standing, the head can be tipped back with the eyes looking upwards and the lower lid should be pulled down. Once the bottle is squeezed the drop should fall into the gap between the pulled lower lid and the eye. Alternatively, a mirror can be used for guidance with the head in a normal position, and the drop squeezed into the same gap as mentioned above
• After the drop has been applied, the eye should remain closed with a finger gently pressing on the inside corner for about a minute so that minimal wastage occurs. This ensures the drop is absorbed sufficiently
• If any other drops are prescribed in addition, it is best to wait at least 5 minutes before applying these
• Contact lens wearers should apply drops at least 15-20 mins before they apply contact lenses to the eye
• Always follow the advice and instructions given to you by your prescriber
• Be careful not to touch the tip of the bottle (nozzle) onto the eye surface to help avoid contamination
• Never use drops after the expiry date printed on the bottle. Always discard the bottle once open after the recommended time from opening (usually 4 weeks)
• You should be advised accordingly if the drops need to be refrigerated

Author: Serena Kalsi, Professional Relations Consultant - Bausch + Lomb UK