No surgery
Contact lenses cure shortsightedness


By J. Chun

Wearing orthokeratology lenses is a new and safe way to cure shortsightedness without undergoing surgery.

These lenses cure shortsightedness by reshaping and flattening the corneas of eyes to reduce the focusing power.

To have an accurate control of the amount of flattening, a registered optometrist first utilizes videokeratography, a computerized imaging technology, to determine the shapes of a patient’s corneas prior to treatment.

The optometrist determines the suitable type of orthokeratoloy for the patient based on the information from the videokeratography.

After that, the patient needs to consult the optometrist regularly to prevent potential problems. The consultation period normally lasts for half year.

In addition, the orthokeratology lenses should be worn overnight to continuously reshape the corneas.

Otherwise, the level of shortsightedness rises back to the original level in one or two days.

Edwin Wong, a registered optometrist for Eye-Care Pro Optometry Clinic, said, “The main advantage of orthokeratology lenses is to reduce people’s dependency on wearing glasses.

“And the risk is low because it is a non-surgical process.”

However, recent news articles have reported that orthokeratology lenses lead to diseases and permanent damage to eyes.

The Department of Ophthalmology and Visual Sciences at The Chinese University of Hong Kong has found at least six cases of cornea ulceration due to the use of orthokeratology lenses.

A corneal ulceration results from a pitting of the cornea, generally from an infection by bacteria, fungi, viruses and sometimes from an injury.
In one case, a 9-year-old girl lost 50 percent of the eyesight in her left eye.

On the other hand, Prof. George Woo, dean of the Faculty of Health and Social Sciences and chair professor of Optometry at The Hong Kong Polytechnic University, said that proper use of orthokeratology lenses does not cause any problems to eyes.

The unsuccessful cases are not representative. They constitute no more than 1 percent in over 5,000 users.

Mr. Wong said, “Frequent and thorough communication between patients and optometrists can minimize the damage to eyes.

“Patients play the most important role in the follow-up regular checking.

“They should take the initiative to consult an optometrist.”

Daisy Ho is a Year 3 student in The Nethersole School of Nursing at the Chinese University. She has used orthokeratology lenses for three years.

“At the beginning, I had an inflammation of the eyes after starting to wear orthokeratology lenses.

“Later I consulted the optometrist regularly, and it was soon discovered that I had used the wrong cleaner solution to clean the lenses,” said she.

Prof. Woo also agrees that the “patient-compliance” of consultation is the most essential factor to keep eyes healthy.

However, he said there is a problem in the qualifications of optometrists.

“Not all optometrists in Hong Kong are eligible for fitting contact lenses for customers,” said he.

In Hong Kong, registered optometrists range from Part I to Part IV. Optometrists in the Part I category are the most qualified.

Prof. Woo said, “Nearly half of the registered optometrists in the category of Part IV are not allowed by law to fit contact lenses for customers.”

There are nearly 1,900 optometrists in Hong Kong, among which about 700 are not qualified for fitting contact lenses for customers.

Therefore, customers should pay attention to the qualifications of optometrists when they buy contact lenses.

The words “Restricted to refraction only” appear on the optometrist’s certificate if he is not allowed to fit contact lenses for customers.

“Actually the main cause of diseases and damages to eyes relates to the quality of optometrists instead of orthokeratology lenses,” said Prof. Woo.

Moreover, The main competitor of orthokeratology lenses is “Laser in-Situ-Keratomileusis”, or LASIK.

This laser surgery changes the curvature of corneas by removing tissues within them.

Concerning prices, orthokeratology lenses range from $8,000 to $14,000 while LASIK costs $14,000 on average.

“Because the cost of LASIK has been decreasing in recent years, it is becoming increasingly attractive to people,” said Mr. Wong.

Also, LAISK is a once-and-for-all operation that involves no continual consultation as orthokeratology does.

But there is a risk of LASIK because it removes tissues from the corneas.

Nevertheless, Mr. Wong does not expect orthokeratology lenses to sharply capture a greater market share in the near future.

He said, “The lowering cost of LASIK draws potential customers away from orthokeratology lenses.

“Besides, services of the lenses are highly individualized, requiring optometrists to show intensively care to each patient.”

However, there is a lack of qualified optometrists to meet large-scale demand.

Added he: “Proper training is inadequate because additional courses for further qualifications require enrollment fee.

“As a result, students are usually deterred from taking these courses.”

Orthokeratology lenses face both challenges and difficulties in the Hong Kong market.

Orthokeratology lenses cure shortsightedness by reshaping and
flattening the corneas of the eyes.