By Eyecare NGTypes | Complications | Contraindications
“I don’t like glasses and I am scared of inserting contact lenses, what other options are available for me”?
“Are there other options for the correction of refractive errors apart from glasses and contact lens?”
The quotes above are about the most common questions most eye doctors encounter in and out of their clinics. Some people who have refractive errors do not like wearing glasses especially those whose refractive errors are significantly high and are offered thick lenses.
Refractive errors are optical defects that prevent light rays that enter the eye from focusing exactly on the retina. This results in blurry vision along with other symptoms. Learn more about refractive errors.
Refractive errors are traditionally corrected with spectacle lenses (eyeglasses) and contact lenses. With advancements in eye care, they can now be corrected permanently with surgery. Therefore, people who do not want to wear eyeglasses or contact lenses can opt for surgery if it is indicated for them.
It is, however, important to note that some refractive surgeries are irreversible and sometimes they do not completely eliminate the need for eyeglasses or contact lenses. Depending on the nature of refractive error and outcome of the refractive surgery, there may be a need for low power lenses to supplement distance vision. If surgery is done before age 40, as presbyopia sets in with age, reading glasses may become necessary.
There are different types of refractive surgeries. They generally involve reshaping the surface of the cornea or implanting an artificial lens (intraocular lenses) in the eye. Examples include:
Laser-assisted in-situ Keratomileusis (LASIK)
This is the most common laser refractive surgery done all over the world. It reshapes the surface of the cornea using laser. This procedure can be used to correct myopia, hyperopia and astigmatism. Recovery from the LASIK surgery is known to be fast with fewer complications.
Photorefractive keratectomy (PRK)
Just like LASIK, this is a laser refractive surgery. It is used to correct myopia. Compared to LASIK, recovery from photorefractive keratectomy takes a longer time.
Phakic intraocular lens (IOL) implantation
This is a refractive lens surgery in which an intraocular lens is implanted into the eye while the natural lens is still in place. The intraocular lens is placed behind the iris (the coloured part of the eye) and in front of the natural lens. It is often used to treat high myopia. The advantage of this type of refractive surgery is that it is reversible.
Refractive lens exchange
This is also known as lens replacement surgery. It involves the removal of the natural lens as is done in cataract surgeries and its replacement with an intraocular lens. Unlike cataract surgery, the natural lens, in this case, is still clear. This refractive surgery is done for people who have high hyperopia or presbyopia and want to reduce their dependence on reading glasses or bifocals.
Complications can result from refractive surgeries; though they are becoming minimal as eye surgeons perfect their skills and techniques. Some complications include:
- Dry eyes: This is a very common complication, especially for LASIK surgery.
- Protrusion of the cornea (keratectasia)
- Corneal haze or scarring
- Cystoid macular oedema – Swelling of the macula (the most sensitive part of the retina responsible for central vision). Can occur with refractive lens exchange
- Eye infection
- Posterior capsule opacification: This can also occur after refractive lens exchange
Contraindications for refractive surgeries
Generally, refractive surgeries are contraindicated in conditions where the refractive error is unstable or in cases where there are corneal abnormalities or in people that have uncontrolled eye diseases or health conditions that affect the eyes. Some specific situations where refractive surgeries are contraindicated include:
- Age less than 18 years: The younger a person, the higher the probability of changes in the degree of refractive errors as the person grows. The probability for significant change reduces from 18 years.
- Uncontrolled glaucoma
- Exudative macular degeneration
- Very thin cornea
- Corneal diseases like keratoconus and Herpes keratitis
- Systemic conditions such as rheumatoid arthritis
- Immuno-compromised people
- Dry eyes