Eyecare Tips

Orthokeratology in Myopia Control

2018/07/23

WHAT IS ORTHOKERATOLOGY

• is a non-surgical procedure, thus free from any risks or side effects related to surgery.
• Using high oxygen transmitted lenses to alter the shape of the cornea in order to decrease myopia; images can then be formed back on the retina. It can also be used to slow down the progression of myopia
• Lenses are to be worn overnight, during sleeping hours and be removed on awakening. Orthokeratology lens wearer can have dear vision and be free of any spectacle aids during most waking hours. It’s safer and more convenient for those playing sports.
• Changes in corneal curvature are only temporal. The cornea will always return to its original shape if lens wear is stopped.
• According to previous researches done by The Centre for Myopia Research of the Hong Kong Polytechnic University, the progression of myopia is decreased by 50% on those children wearing orthokeratology lens, compared to those wearing normal glasses

Who is suitable for orthokeratology?

• Myopia under-4.50DS; astigmatism under -1.50DC or those who want to control the progression of myopia.

SPECIAL CAUTION

• Proper lens insertion, removal and cleaning regimen are essential to minimize the risk of infection.
• Kids wearing orthokeratology lenses should be monitored/ supervised by parents for hygienic purpose.
• Lenses should be thoroughly cleaned and disinfected everyday. Protein removal has to be done on a regular basis.
• The outcome of orthokeratology varies from individuals. A low power prescription glasses might be needed during the day.

Interested in orthokeratology lenses?

• Those who are interested should undergo a comprehensive eye care examination and an orthokeratology assessment Regular aftercares will be performed by optometrists during lens wearing period; lenses will be changed according to corneal changes to ensure a healthy cornea.
• All optometrists in PolyVision, registered Part I optometrists, are able to use diagnostic drugs to perform a comprehensive eye examination before any orthokeratology begins. All centres are well equipped and available for all the assessment, trial lens fitting, lens ordering (2-4 weeks), lens wearing and follow up service.

FREQUENT ASKED QUESTIONS

Q1 Can myopia be decreased to zero by wearing orthokeratology lenses?

• Orthokeratology lenses can only slow down the progression of myopia; existing myopia prescription cannot be treated or cured

Q2 Is orthokeratology lenses safe to wear?

• There are potential risks for any contact lens wear. If patients can follow the given instructions in lens wearing schedule and lens cleaning, orthokeratology lenses will cause no harm. In case of any discomfort during lens wear or after lens removal, please stop lens wear and contact the optometrist. Those having eye diseases, dry eye syndrome, eyes allergy or non-regular sleeping hours are not suitable.

Q3 Can orthokeratology lenses improve our eyesight?

• Outcome varies from individuals. Whether one can have good vision after lens removal depends on individual, factors include:

– Degrees of myopia and astigmatism

– Corneal curvatures and corneal stiffness

– Lens centration (any eyes rubbing causing lens dislocation during sleep)

– Wearing time (sleeping hours)

– Tears adequacy

• Non-ideal corneal curvature change or residue myopia will end up with mildly blurry vision during the day or later in the afternoon, glasses might be needed to help accordingly.

Q4 Will eyes rubbing during sleeping hours affect the outcome or the health of the eyes?

• If orthokeratology lens is dislocated from eyes rubbing, vision might be affected in the morning and the cornea might be scratched. Minor corneal injury will be recovered few hours after lens removal. Serious corneal injury must cease lens wear and/or refer to the Ophthalmologist.

Q5 Is frequent lens change necessary during the lens wearing period?

• Lens change depends on the power of myopia and astigmatism, corneal reaction and outcome. Same lens might be used if there is no residue myopia and fitting is optimal. Optometrist might need to have minor adjustments with the orthokeratology lens if there is any residue myopia in waking hours. Since the high oxygen transmitted orthokeratology lenses can easily be scratched or have an accumulation of deposits, yearly lens replacement is suggested to maximize hygiene and corneal health.

Q6 Do I still need to do follow up or wear lenses after few years of orthokeratology?

• If orthokeratology lens is a replacement for spectacles or contact lenses, you have to keep wearing the lenses in order to stabilize the daytime vision. If orthokeratology lens is used to control the progression of myopia, procedure can be ceased after puberty. Patients can then choose to wear spectacles or contact lenses, or continue with orthokeratology lenses. Since hygiene, lens quality and wearing time are crucial in orthokeratology, patients should follow all the instructions given by the optometrist, regular checkups every 3-6 months, never skip any follow up appointments.