TOKYO -- Many young Japanese women are as happy to change their eye colour as to change their shoes, but the government may slap restrictions on the sale of the trendy coloured contact lenses they use, after a series of cases of eye damage.In a study backed by the industry ministry, optometrists reported about 170 cases of eye damage over a two-and-a-half year period among those who used non-prescription coloured contacts.
Several cases required the patients to stay overnight in hospital and some users risked losing their eyesight, according to a statement from the National Institute of Technology and Evaluation.
Coloured contacts are sold in many countries, but millions of pairs are in circulation in Japan, where young women often use them to try to make their eyes look larger. They are currently sold in cosmetics stores and over the Internet, rather than by licensed opticians.
"We see foreigners who have many different eye colours, but Japanese people only have brown or black eyes," said Kanako Tsutsumi, a 20-year-old student who used to wear the lenses.
"I liked coloured contacts because I had black hair and I thought grey contacts would look more fashionable," she said.
She stopped using them after she found they hurt her eyes.
"People assume that if non-prescription lenses are made by the same companies that make regulated prescription contacts, they are applying the same standard to coloured contacts," said Satoshi Nagata, a researcher at NITE. "The results of this study showed otherwise," he said.
The health ministry and the ministry of industry have both decided to regulate coloured lenses under pharmaceutical law within this year, he said.
Under the present law, opticians have to supervise any sale of prescription contact lenses in Japan. However, non-prescription coloured contacts are not subject to such restrictions because they are classified as "beauty goods."
About 30 of the total 170 cases of eye damage in the study were caused by quality problems, such as colour leaking from the lenses. Most of the cheaper colour contacts sold in Japan are imported from South Korea, Singapore, and Taiwan.
Report On Colored Contact Lenses
Colored contact lenses will be placed under similar regulations to lenses for correcting eyesight after a string of reports that colored lenses have damaged some people's eyes, The Yomiuri Shimbun has learned.
The Health, Labor and Welfare Ministry plans to revise the Pharmaceutical Affairs Law to regulate quality and vending of the fashionable lenses as medical equipment.
Colored lenses alter the color of pupils and are available without a doctor's prescription.
About 5 million such lenses--many coming from South Korea or Singapore--are sold annually.
Under the plan, vendors will require permission from prefectural governors to sell colored lenses. Stores would also be required to have supervisors give customers information on the risks involved in using such lenses.
Survey
At least 167 people's eyes have been damaged by colored contact lenses in the past 2-1/2 years, according to a report released Thursday by the National Institute of Technology and Evaluation (NITE).
Only 145 out of about 13,000 opticians surveyed nationwide responded to the NITE survey. Despite the low response rate, 21 people were found to have seriously damaged their eyes and 146 were found to have suffered minor damage from wearing colored lenses.
"Because only a few opticians responded [to the survey], there must be many more cases of people damaging [their eyes]," a NITE spokesman said.
The spokesman also suggested the ministry should regulate colored lenses in a similar way to corrective lenses by making it obligatory for vendors to give customers explanations of risks involved.
After comparing approval regulations for 10 brands of colored lenses with those of corrective lenses, NITE found that colored lenses did not meet thickness standards and--even within the same brand--lens curvature and diameter were inconsistent.
NITE is an independent administrative body that provides technological evaluations of consumer products.
Contact lenses that boost your sight while you sleep
For anyone who wears contact lenses, the rule is simple: remove them before going to bed, or risk a nasty eye infection.
Now there are new contact lenses designed to be worn only at night.
What's more, the lenses promise to correct your sight overnight, so you won't need to wear contact lenses or glasses the next day.
The lenses, designed for people with short sight, work by gently pressing on the eye to restore it to the shape of someone with normal vision.
Around 12 million people in the UK are short-sighted - where distant objects appear blurred - and of them, three million wear contact lenses.
In people with normal vision, light rays pass into the eye through the cornea - the transparent front part of the eye that covers the iris and pupil. The light passes through the lens (responsible for focusing) and towards the retina at the back of the eye.
The retina then transforms this light into image-forming signals which are sent to the brain.
With short-sighted people, the cornea is either too curved, or the eyeball too long. This means the light rays from distant objects focus in front of the retina, rather than directly on it, making objects seem fuzzy.
Overnight lenses are made from a special hard type of plastic lens, called gas permeable. These are already available as day lenses, but most people wear soft lenses as these are more comfortable.
The harder, overnight lenses work for both types of short-sightedness by gently pressing on the cornea, reducing its curvature, and thereby refocusing the light directly on to the retina. It also effectively shortens the eyeball.
The reshaping is temporary, however, because the cornea will gradually spring back to its original shape, so the lenses must be worn every night. (The lenses aren't suitable for people who are long-sighted - where nearby objects are blurred - as their corneas are too flat.)
To get the right pressure, the curvature of the eye is measured - a procedure known as corneal topography. The lenses are then shaped to these contours, so pressure is applied evenly over the front of the eye.
The cornea is usually flattened slightly more than it needs to be. 'By overcompensating, this avoids sight deteriorating past perfect vision during the day as the cornea springs back to its original shape,' says Shelley Bansal, an independent optician in Middlesex, who advises one overnight lens manufacturer.
It's thought the Chinese slept with small weights on their eyelids to reduce short-sightedness
The lenses are also made to the patient's prescription in case they wake up in the night and need to see.
Although they should be worn every night, it takes a few days for the effects to wear off completely. In theory, you could avoid wearing them for a night or two, although your vision would gradually deteriorate.
This technique, known as orthokeratology, has existed for centuries. It's thought the Chinese slept with small weights or sandbags on their eyelids to reduce short-sightedness.
'But until recently,' says Dr Susan Blakeney, optometric adviser to the College of Optometrists, 'it has been considered unreliable, as there was never any guarantee the lenses would work.
'Since then, techniques such as corneal topography - where the curve of the cornea is measured - have developed. This means lenses can be made to fit the curve of each person's eye very accurately.'
An independent review of overnight lenses in general, published in the prestigious journal Clinical And Experimental Optometry, found the new generation of overnight lenses can improve vision by around 70 per cent after one night, often correcting sight fully within a week.
Short-sightedness is usually picked up in childhood or the early teenage years, so it is hoped overnight lenses could at least prevent further deterioration. There are even hopes that, over time, such lenses could permanently repair vision in children.
This comes after scientists at the Hong Kong Polytechnic University suggested these lenses could actually slow the elongation of the eyeball associated with short-sightedness.
One of the latest types of overnight lens is called i-GO, which are said to treat a larger area of the eye than previous designs, meaning sight can be corrected more accurately.
'If this is the case, it's good news,' says Professor David Gartry, consultant ophthalmic surgeon at Moorfields Eye Hospital and The London Clinic.
'Essentially this is a rehash on an existing principle - but if they flatten more of the cornea, the lens will be more effective.'
Overnight lenses are not suitable for diabetics, long-sighted people or those with eye diseases. They are also suitable only for people with a prescription of -5 or less, which accounts for 65 per cent of short-sighted people.
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