Alternatives to Laser Eye Surgery : Laser Eye Surgery
Regular laser eye surgery may not be fully effective on very severe forms of myopia, hyperopia or astigmatism. Each clinic and surgeon will set their own limits on the severity they will treat, and this may also depend on individual circumstances and the patient’s history. In general they are unlikely to perform laser surgery on patients with myopia over -10.00 diopter, or with hyperopia or astigmatism over +5.00. For these patients, other treatment options are available to research and choose from:
Intraocular Lens Implant
In this procedure, intraocular lenses (IOL) are implanted into the eye to replace the natural crystalline lens. While most commonly used to free the lens from a cataract, IOL surgery is also used to improve optical focus when there is a refractive error. Multiple types of lenses are available, some of which only offer near or far focus, whereas others provide clearer vision at all distances. The surgeon uses a very small incision which eliminates the need for stitches, with a patient recovery time of around 2 or 3 weeks. Certain risks are associated with the treatment, as with all surgeries, and you should speak to a qualified opthamologist about your specific refractive error.
A non-surgical alternative to an IOL implant is inserting intraocular contact lenses; these allow similar correction without replacing the original lens. However, this leaves you in a position of wearing lenses once again.
Photorefractive Keratectomy (PRK)
PRK, and also LASEK (Laser-Assisted Sub-Epithelial Keratectomy), are forms of laser eye surgery that differ from the norm. Both of these treatments are essentially the same procedure. PRK can treat myopia up to -12.00 diopter, which is significantly better than average laser treatment. This is achieved by permanently altering the anterior central cornea in shape. An excimer laser removes a little bit of tissue from the corneal stroma near the front of the eye, and precisely corrects the error. In contrast to normal laser surgery, PRK does not leave a permanent flap in the deep corneal layers, helping to maintain structural integrity. No knife or microkeratome is used, but more pain is common.
Conductive Keratoplasty (CK)
This is a non-laser technique which is ideal for those over the age of 40. CK treats astigmatism, hyperopia and also presbyopia (farsightedness with aging). The latter cannot be treated with regular laser eye surgery, as presbyopia does not affect the cornea. CK steepens the cornea by utilizing the heat from radio frequency waves.
Astigmatic Keratoplasty (AK)
AK seeks to change the cornea to its natural and intended spherical shape. Very small incisions to the cornea allow alteration of the corneal curvature. This is most effective on mild astigmatism, but can also be a necessary additional treatment after regular or PRK laser eye surgery.
Orthokeratoplasty
Orthokeratoplasty is particularly useful for young children who do not qualify for laser eye surgery and whose eyes are still developing. Rigid gas permeable contact lenses are implemented to reshape the cornea, usually during a night’s sleep. A timetable of wear is set out depending on the specifics of each case. After removing these lenses, vision is temporarily fixed.