Thursday, June 08, 2006

New LASIK technology reduces post-operation side effects

A new LASIK technology for myopia has been developed to reduce the side effects of such surgery, and it will cost only 10 percent more than the standard procedure.

LASIK is becoming a popular procedure to correct myopia.

While it promises near perfect vision for all, about 5 percent of those who went for the treatment experienced side effects such as glare, halos and night vision problems.

This is because in standard LASIK surgery, the shape of the patient's cornea is slightly altered to correct myopia, affecting the naturally elliptical shape that allows better contrast and clarity, especially in dim light.

Doctors say that currently this can be corrected through prescription glasses or wavefront surgery.

But the new Zyoptix Aspheric LASIK Technology (from Bausch and Lomb) promises to reduce such side effects.

Dr Chan Wing Kwong, Head, Refractive Surgery Service, Singapore National Eye Centre, explained, "In patients with high myopia, sometimes with the excessive flattening of the high cornea in the highly myopic patients you do induce some problems like night time vision, glare and halo, and some patients who have large pupils...will feel (these) effects more. So if you flatten the cornea too much in a conventional treatment, these are some of the problems you'll get. Zyoptix Aspheric LASIK understands that there is a problem like that and its specific laser algorithm will try to preserve the ideal shape better.

"There is no way not to correct the myopia without flattening the cornea, but in this new way of lasering the cornea, it tries to flatten the cornea while preserving the good shape of the cornea, so that you have less risks of night time vision problems."
Doctors say that this technology is best suited for those with very high myopia, thin corneas and large pupils.


A clinical trial on the new technology, involving 85 patients from three Asian countries, including Singapore, was carried out from September to December last year.

97 percent of patients who had the Aspheric LASIK surgery attained perfect vision.

More significantly, nearly half or 47 percent could see better at night or in low light conditions, compared to only 27 percent of patients who underwent standard LASIK surgery.

Zyoptix Aspheric better preserves the corneal shape which translates into better visual performance for the patient, with changes in corneal curvature reduced by 60 percent.
Forty of those patients were from The Eye Institute at Tan Tock Seng Hospital and the Singapore National Eye Centre.


Doctors say that Singapore was chosen to be involved in the study as it has one of the highest myopia rates in the world - with more than 10,000 LASIK surgeries done here every year.
The other two centres involved were the Rutnin Hospital in Bangkok, Thailand and the Asian Eye Institute in Manila, the Philippines.


The new LASIK technology will be launched during an international eye conference in Singapore this weekend.

It will be made available at all major eye centres, in Singapore and worldwide, soon after.

Source : Channel News Asia