No sight for sore eyes

Perfect vision is a blessing enjoyed by very few. Most people need help to see clearly.

That support usually comes in the form of a corrective lens, and for increasing numbers of people, that means a contact lens.

However, while these delicately crafted, thin optical discs bring clarity to the blurred vision of millions around the world, many of them could also be putting their vision at risk.

A recent survey by Biotrue contact lens solution found that more than 90 per cent of contact lens wearers regularly wear them for longer than recommended by their optometrist. And one in five confess they’ve worn their lenses for a full 24 hours longer than advised.

While wearing lenses for too long can cause discomfort and make vision blurry, it can also lead to more serious infections, especially if coupled with unhygienic care of your lenses.

Optometrist Brian Tompkins explains: “If you don’t take proper advice about contact lens wear, the worst case scenario is a nasty microbial infection that

can lead to the loss of an eye.

“The bugs eat the cornea and destroy the vision, if you’re not careful.” Such infections are rare. Far more common problems are those associated with not enough oxygen and moisture getting to the eye.

Dr Susan Blakeney, clinical adviser at the College of Optometrists, explains that keeping the eye moist with tears is particularly important for contact lens wearers, firstly to create a smooth optical surface for light to pass through for clear vision, and secondly to keep soft lenses hydrated.

“If you haven’t got enough tears, the lens dries out and that can make it uncomfortable, as well as not doing your vision any good,” she says. Office-based jobs can exacerbate the problem. Staring at a computer all day reduces blinking, which makes the eye drier, and air-conditioning can also make lenses uncomfortable.

Tompkins says there are options other than removing lenses and wearing glasses though. Taking a break from staring at a computer, and rolling the eyes help. The meibomian glands around the eyelid, which secrete the oily layer of tear film, can also be massaged, and sometimes heated, to help produce tears more efficiently, or artificial tears can be put into the eye.

In extreme cases, a tiny punctal plug can be inserted into the eye’s tear duct to block it and prevent liquid draining out. As the eye gets most of its oxygen from the air, it’s important that lenses let oxygen through. Most modern lenses are extremely permeable, says Blakeney, but if worn for longer than the recommended time over a prolonged period, blood vessels in the white of the eye can start to grow into the cornea over the front of the eye.

“It’s a long-term complication that can occur over months or years,” she warns.

“If the blood vessels do that, it won’t do your vision any good, and it’ll affect your ability to wear contact lenses.”

Very few people are unable to wear contact lenses, agree Blakeney and Tompkins, and with the advice of an optometrist, there’s a huge selection to choose from, ranging from lenses that can be disposed of every day, week or month, to bifocals, lenses you can sleep in, and lenses that change the shape of the eye during the night and are not worn during the day.

Some people buy lenses off the internet after having their eyes tested by an optometrist and getting a prescription. However, Blakeney warns: “If you do get

lenses online, it’s really important to ensure you only get the same type of lens that’s in your contact lens prescription.

“Don’t be fobbed off with a cheaper type - you might be saving yourself money but storing up problems, as they might not be suitable at all.”

The key to healthy eyes is to follow the wear time and hygiene advice given by your contact lens practitioner, says Blakeney. After all, it’s there for a reason and it’s better to be safe than sorry.