Medical Optics

Dry Eye

Dry eye is a common condition that is experienced by very many people. It can vary from as little as mild dry eye with no visual effects to a severe form of keratoconjunctivitis sicca that can cause blurring of vision and occasionally blindness. However, the vast majority of cases of dry eye are not serious and can be managed or self treated by simple means.

Symptoms usually described by patients are grittiness, stinging or discomfort of the eyes. These symptoms occur or get worse in drier situations such as warm kitchens, centrally heated rooms, poorly controlled air conditioning, heated cars, airline flights, very dry weather and in fact any situation that reduces the humidity of the surrounding air.

Treatment

Sufferers should try and control their environment whenever this is feasible. For example if you are baking a cake in the kitchen you could consider boiling some water in a pot to allow steam to permeate the room thereby increasing the humidity of the air. Symptoms of dry eye can sometimes develop when individuals are reading, working on a computer or watching the television. The reason this occurs is that concentration often reduces the blink rate thereby causing the symptoms of dry eye. It is helpful to blink more frequently if you can develop this habit. Youngsters playing computer games for a prolonged period often end up with red eyes from the dryness caused by reduced blinking while concentrating. They never seem get red eyes get while doing their homework.

If simple measures do not help your symptoms then you may have to resort to the use of lubricating eye drops in certain situations. There are many companies manufacturing these drops and your pharmacist will tell you of the more popular brands.

Dry eye is also sometimes associated with certain medical conditions and can be the initial presenting symptom occasionally. If you find yourself using lubricating eye drops at an increasing rate then you should seek a medical opinion from your GP or eye doctor. Dry eye can also be associated with other eye conditions such as meibomitis and blepharitis (both eyelid conditions) and advice from your eye doctor on the treatment of these conditions is advisable.

More severe cases of dry eye are difficult to control but there are certain treatments that can be recommended by your eye doctor such as a strict lubricating regime, conjunctival inserts, punctal plugs, punctal surgery and lid surgery where indicated.

It is my experience that most patients with dry eyes do not use enough lubricating eye drops. Sometimes it is a good idea to use eye drops very frequently for example every 15 minutes while watching the television, working on your computer or reading. Make sure you use preservative free eye drops when instilling drops very frequently.

Pink (Red) Eye

Pink or red eye is a term used to describe inflammation of the conjunctiva and the medical description of this in one word is ‘conjunctivitis’. The term conjunctivitis is a word used to describe any inflammation of the conjunctiva and does not necessarily mean that there is an infection present. Most cases of red or pink eye are not contagious. The conjunctiva is the epithelial protective covering of the white of the eye and also covers the inside surfaces of the eyelids.

The causes of pink eye are many and varied. The red or pink colour is due to the dilation of blood vessels within the conjunctiva. Blood vessels dilate in a response to assaults of various kinds. For instance if the eye becomes dry it will appear as a pink eye. An example of this would be a child who plays computer games and will not blink in case he loses the game. After a while due to lack of lubrication the eye will react by becoming red in colour. The cornea is the front transparent surface of the eye and if it becomes dry it will be affected by dry spots which in turn cause redness. Any infection of the cornea or conjunctiva will cause redness.

Typical causes of conjunctivitis include

The relatively common condition called adenoviral conjunctivitis that cause bilateral pink or red eye. The red eye caused by this virus can be quite dramatic looking and the eyes can be quite irritated, watery and sticky. It is highly contagious and can sometimes be associated with a cold or flu-like symptoms. This condition spreads rapidly through class rooms and often teachers suffer from this condition as well as other people who care for children. The treatment for this condition is “supportive” as antibiotics will not help so lubricants and cool compresses can help the symptoms, usually the condition resolves within a week or two but occasionaly this condition can still cause pink or red eye for months after the infectious stage.

Sometimes bacterial infection form a cold or sinusitis or from contact with another person with bacterial conjunctivitis can be the cause of a red eye. In addition to red or pink eye, bacterial conjunctivitis can also be associated with a sticky mucus, or even yellow pus, which has often to be wiped off in the mornings (Picture 1). These cases should be treated with antibiotic eye drops that your doctor will prescribe.

Picture 1: Bacterial conjunctivitis associated with sticky mucus, or even yellow pus

Sore red eyes from over-wearing your contact lenses, such as sleeping in them, can be a cause for concern. If you have a red eye from this cause the contact lens should be immediately removed and medical help should be sought if the condition doesn’t settle within a few hours.

‘Dry eyes’ is a very common cause of pink eye due to inadequate tear production and lubricant eye drops can be very useful in treating this condition. If you suffer from persistent dry eyes then you should visit your doctor who will refer you on to an ophthalmologist (eye doctor) if this is indicated.

Dry eyes are often associated with the skin condition rosacea. This condition is very common in Irish people and red or pink eye is often the result (Picture 2). In this photo you can see not only the red eye but also the red skin ‘rosacea’.

Picture 2: Red or pink eye with rosacea skin condition

Warnings:

• If the eye is pink or red and associated with pain then it is essential that you seek medical help
• If you have a red or pink eye associated with contact lens wear then medical help should be sought immediately
• A more serious condition causing red or pink is iritis or uveitis. This condition is associated with deep pain in the eye and an eye doctor should be consulted
• A foreign body in the eye will cause irritation as well as pink or red eye and this needs to be diagnosed and treated by your own doctor or an eye doctor