With World Glaucoma Week running from March 11 to 18, Dr Zak stresses the importance of regular eye checks

OF all the five senses, arguably your sight is the most important to independent living. However figures from a leading high street optician show that up to a third of individuals had not been for a routine vision test in the last two years, despite four fifths of those asked being aware that such a simple assessment could prevent sight loss.

Glaucoma is one of the leading causes of blindness worldwide, with an estimated two per cent of the UK population older than 40 having the disease.

The eye constantly produces a fluid which needs to drain away at a steady rate to maintain a healthy pressure in the eye. Blockage of drainage channels prevents this from happening.

The excess fluid causes increased pressure within the eye, with damage to the nerve at the back of the eye, known as the optic nerve. This is responsible for sending signals from the eye to the brain, which processes them into the images we see.

As blockage of the drainage channels often happens over several years, you may not initially notice any deterioration in your sight at all or there may be subtle changes, most often blurring of your peripheral vision. Most people are diagnosed in their 70s and 80s.

Acute glaucoma is a very different picture, and occurs when the drainage channels become obstructed suddenly and the pressure in the eye rises rapidly.

The hallmarks are an immediately painful, red eye and blurred vision.

Typically sufferers will be unwell with nausea, vomiting and headache. This is a medical emergency and anyone with these symptoms must get themselves to the nearest Accident and Emergency or Eye Casualty Department immediately.

THERE isn’t a cause as such for glaucoma, but we know that persons of Asian, African and Caribbean origin are at greater risk.

Similarly a family history of glaucoma, other sight problems, diabetes and high blood pressure also play a part in developing the disease.

Treatment for chronic glaucoma starts with eye drops to lower the pressure in the eye. If this is unsuccessful, laser treatment or surgery may be needed to open up the drainage tubes. The second two methods may also be needed for acute glaucoma.

However, with prevention better than cure, the take home message is to attend regular sight tests.

These last no more than an hour during which photographs of your optic nerves will be taken and your eyesight including peripheral vision tested.

In addition, the pressures inside your eye will be measured. None of these procedures are painful and if you have a family history of glaucoma, you may qualify for this service free of charge.

Regular checks will not only detect glaucoma, but also other diseases which may not have any obvious symptoms at an early stage.

Timely recognition and treatment is important to maintain vision, as once it is lost, sight cannot be recovered.

If you haven’t had a test in the last two years, please make this one of your priorities.