All About Laser Refractive Treatment
The information given to you here allows you to make an informed decision about having excimer laser refractive surgery for your short-sightedness (myopia), long-sightedness (hyperopia) astigmatism. Please take your time to consider this information carefully. If you feel the information is incomplete or you do not understand it fully, we ask that you question your eye care professional on any aspect of the procedure that is unclear. We would like all your queries answered to your satisfaction and to the best of our knowledge before you sign the form.
LASIK (Laser In-Situ Keratomileusis)
* Laser In-situ Keratomileusis (LASIK), in use since 1991, has become the accepted standard form of refractive surgery internationally. It is used to correct higher degrees of short-sightedness (myopia), long-sightedness (hyperopia) astigmatism and presbyopia. To help you understand the above terms it might be helpful to refer to the GLOSSARY
A thin flap is created in the front of the cornea using the highly accurate Visumax femrosecond laser.
The flap is lifted and the Mel 90 excimer laser used to precisely reshape the underlying corneal bed to change the focus of the eye. The flap is then replaced and correctly re-positioned over the modified corneal bed, conforming to the new shape. LASIK offers quicker visual recovery and minimal post-operative discomfort.
PRK (Photo Refractive Keratectomy)
Is an earlier form of laser refractive surgery. No corneal flap is made. The corneal epithelium (front cell layer of the cornea) is removed, the cornea then reshaped with the excimer laser. It takes approximately three days for the epithelium to heal. During that time one can experience mild pain, or moderate discomfort and the vision will be blurred for a week or more.
PRK was first performed in 1988. It is a procedure that produces good results that has been superseded by LASIK but in certain cases may be a preferred treatment.
SMILE (Small Incision Lenticule Removal)
SMILE was first pioneered some 10 years ago with over a million procedures now performed worldwide. The Visumax laser separates a thin convex shaped lenticule within the cornea that is then extracted through a small incision. SMILE is now replacing LASIK as the preferred procedure for low to moderate degrees of myopia.
Other Refractive Options
In deciding to have excimer laser surgery, you should understand that there are other successful methods of restoring useful vision to patients with short-sightedness, long-sightedness, and/or astigmatism. These are:
- GLASSES: glasses have been and still are the most common method of correcting vision for patients affected by short-sightedness, long-sightedness and/or astigmatism.
- CONTACT LENSES: contact lenses are available for the correction of short-sightedness, long-sightedness, and/or astigmatism as either gas-permeable hard lenses, soft lenses or disposable lenses.
Bifocal contact lenses are now available for presbyopia. Not everyone is able to wear contact lenses and this may be for a variety of reasons.
With both the above methods of treating short-sightedness, long-sightedness, and/or astigmatism, the treatment is only effective during the period the patient wears the glasses or contact lenses.
- RADIAL KERATOTOMY(RK): RK was widely used in the 1980s and early 90s but has now been superseded by laser refractive options. A series of controlled deep cuts are placed in the cornea resulting in it flattening out correcting lower degrees of myopia.
- I.C.L'S: (Phakic) A contact lens is inserted inside the eye, no corneal tissue is removed. This is a more invasive procedure - normally for those not suitable for laser surgery.
- INTRACORNEAL RINGS: Intracorneal rings: Rigid ring segments are inserted into the peripheral corneal stroma to strengthen and stabilise it typically used for Keratconus and in conjunction with corneal cross-linking.
- KERATOPLASTY: Pulses of radio frequency energy heat and shrink the outer edges of corneal tissue to reshape the centre of the cornea. Treatment most commonly used for hyperopes. Now been replaced by more stable and reliable laser treatments.
- LASEK: A modification of PRK where a corneal epithelial is created and acts as a tempory dressing for the cornea.
- ORTHOKERATOLOGY: A rigid contact lens is worn at night with the aim of changing the shape of the cornea so no lens will be needed during the day. The effect is limited and unpredictable.
- INTRACORNEAL INLAYS:Either a small disc with a central “pinhole” to increase depth of field for reading “Kamra” (no longer in use) or a small lenticule to create a bifocal cornea. Although removable the foreign body affect is not reversible.
- LENS EXTRACTION: Cataract extraction and replacement of the cloudy lens with an artificial lens (IOL) is the most commonly preformed operation in the western world. In some cases Laser Refractive surgery may not be the best option with removal of the biological lens and replacement with an IOL is a better option. Measurements and calculations are carried out pro-operatively and an IOL selected to correct refractive errors including astigmatism and presbyopia (see Symfony IOLs)