New laser treatment will have smile in eyes soonerLocal | Carain Yeung 15 Nov 2016
A new laser eye surgery technique called SMILE shortens recovery time and reduces dry eyes by half compared to the traditional LASIK surgery, doctors said.
LASIK surgery has been widely used to correct myopia, hyperopia, and astigmatism, but ophthalmology specialist Jeff Hui Yung-lam said patients have to use eye drops to ease the dry eye condition for months after the procedure.
This is due to about a 20-millimeter cut at the cornea created for the ablation process to shape the corneal curvature to correct sight, Hui said, adding that the cut affects the nerves at the structure and as a result tear production.
Natalie Mitchell, a TV host, has been troubled by myopia and astigmatism for years. Since she started her job seven to eight years ago, Mitchell said she had been suffering from inflammation two to three times a year.
"I sometimes get off work very late and have to wake up very early in the morning.
"Whenever I work, I have to wear contact lens and makeup and that sometimes go for 10 days straight when I get busy."
Many Hongkongers share the pain as ophthalmology specialist Teresa Lau Tze-yan said about 70 to 90 percent of young people have myopia and contact lens have become a more popular choice.
Lau said the contact lens cover the cornea directly and therefore trapped away the oxygen, which reduces tear production.
She said tear serves antiseptic and lubricating functions and therefore those who suffer from dry eyes are also likely to suffer from inflammation.
With a more advanced laser system, Hui said a lenticule is created in the cornea to be removed through a two to four mm long cut to correct the sight problems.
Only five minutes is needed for both eyes with the new technology, while LASIK takes about 15 minutes, Hui said.
"Patients will feel like having sand in their eye the day of the surgery," Hui said, adding that the mild discomfort normally goes away the following day.
Citing a 2015 US study, Hui said 80 percent of the patients who underwent the latest SMILE surgery do not have to use eye drops for dry eyes six months post surgery, while 57 percent of those who took the traditional LASIK surgery have to do so.
A big contrast is also noticed in the recovery period of the two generation of laser eye surgery, with SMILE taking days and LASIK taking weeks or even months, Hui said.
Lau said the chances of infection for the latest surgery is also lower, with the cut smaller and opened at the top of the cornea covered by the eyelids.
SMILE, introduced to Hong Kong since June 2014, costs HK$30,000, about 1.5 times of LASIK, Lau said.