What are corneal ulcers?

Do you wear contact lenses? Do you ever swim or shower in your contact lenses? If you answered ‘yes’ to both of these questions, then your risk of developing a corneal ulcer is significantly raised. Corneal ulcers are painful sores that develop on the cornea (the transparent layer on the front of the eye that covers the pupil, iris and anterior chamber). Professor Parwez Hossain, a leading ophthalmologist, details what this eye condition is and why they are important to be aware of. Whilst corneal ulcers are dangerous to our vision, they are not all that uncommon either.

What does a corneal ulcer look like?

A corneal ulcer is a general deficit of the front surface of the eye (the cornea), usually going through the very superficial layers (the corneal epithelium) and the normal light reflex that comes off the eye, the lustre of someone’s eye gets lost. When someone sees an ulcer in the early stages, the smooth surface of the cornea is lost and the light reflex becomes very regular. In more advanced cases of corneal ulcers, the cornea and ulcer look white, so the patient ends up having a white eye with the pupil and iris features difficult to see.

What do they feel like?

Corneal ulcers are extremely painful. The cornea is one of the most innovative parts of the body and is ultra-sensitive to any irritation. An example or comparison of that could be when you have a grain of sand on your finger, and that same grain of sand is in your eye. You can see that there is a huge difference in the sensation of the same grain of sand. Hence, a corneal ulcer is extremely painful and vision often becomes blurred and also, the eye becomes very light-sensitive.

Are corneal ulcers contagious?

Quite often a corneal ulcer is due to an infection. Infection is usually transmitted by something externally, or from contact lens use. Once an infection is established in the cornea, it is unlikely that it can be transmitted to another person, unless that person is sharing the same contact lenses, or sharing their contact lens solution. Generally, therefore, corneal ulcers are not contagious.

Are they dangerous?

Corneal ulcers can be extremely dangerous. The cornea is only half a millimetre thick and when there is a deficit in the cornea, then the cornea can become thinner and thinner and it can perforate, releasing the contents within the eye out through it. This would constitute a medical emergency, especially in the presence of infection. Infections of the Pseudomonas bacteria can proliferate very quickly in the ulcer area, causing more tissue damage, further ulceration and thinning of the cornea resulting in perforation.

Who is at risk of developing corneal ulcers?

Corneal ulcers in the UK predominantly result from contact lens wear. All contact lens hygiene is a major factor in developing these. Therefore, any contact lens wearer, particularly if they are soft contact lens wearers, if they’re showering or swimming in lenses are particularly at risk of developing a corneal ulcer. Also, patients who are wearing contact lenses who have dry eye syndrome can develop corneal ulcers. Anybody who has poor levels of contact lens hygiene is at risk of developing corneal ulcers.

In addition to that, there are patients who don’t wear contact lenses who develop corneal ulcers and these are patients who may have had trauma to the eye, may have ocular surface diseases, such as severe corneal dryness or they may have problems such as irritation to the eye from an ingrowing eyelash, and often that can lead to a corneal ulcer developing.

How can I avoid them?

Contact lens use is the cause of the majority of cases of corneal ulcers in the UK, so this can be avoided by practising good contact lens hygiene, as well as:

• Wearing the right or appropriate lenses.
• Avoiding showering or swimming in contact lenses.
• Making sure that you follow the instructions as advised by the optometrist in terms of limiting the wear of contact lenses.
• Dealing with the issues of dry eyes that might coexist if somebody is wearing contact lenses, especially if over the age of 45.
• Trying to seek attention when the eye becomes uncomfortable or painful from an ophthalmologist or an optometrist to check for the presence of ulceration on their cornea.
• Trying to avoid ocular trauma to the eye by wearing suitable protection during work, DIY or in places where there is a high chance of getting items in the eyes. Eye protection is usually provided at places of work where it is deemed necessary.

Anybody who receives trauma to the eye is at risk of developing corneal ulceration, so if there is any pain, discomfort, irritation in the eye and sensitivity to light or anyone who is concerned that they are developing ulceration in their eye, should seek urgent ophthalmic medical advice.