Astigmatism is a refractive error of the eye (like myopia and hyperopia). Refractive errors are the result of the shape and size of the eye (as opposed to a developing disease or condition) and must be corrected physically.
Refractive errors are quite common, with nearly half the Canadian population wearing some type of corrective lens (either eyeglasses or contact lenses) to correct them.
Astigmatism is a result of the eye being irregularly shaped; this shape influences how light enters the eye and where its focal point is.
In a “normal” eye, the focal point of the inbound light is directly on top of the retina. In someone with astigmatism, the focal point can be both in front and behind the retina. This irregularity results in impeded vision for both near and far objects,
Like other refractive errors, astigmatism is diagnosed during a comprehensive eye exam. The Optometrist will perform several tests that will indicate the presence of astigmatism, including a visual acuity test, and testing performed via an autorefractor.
Refractive errors are physical abnormalities of the eye and can not be treated with oral medications or eye drops.
Corrective lenses are the simplest and most affordable way to correct astigmatism. Other options, such as laser refractive surgery, are also effective (albeit more expensive).
The most common method of treatment for astigmatism is the use of corrective lenses via eyeglasses. The lenses will correct the refractive error and influence how light enters the eye. In so doing, they correct the problem and facilitate improved vision.
Similar to eyeglasses in method, but different in form, contact lenses alter the way light enters the eye and thus correct the refractive error. Unlike eyeglasses, contact lenses do not change your appearance and are preferred by many as a result.
Strong cases of astigmatism can also be effectively treated with gas-permeable contact lenses. These lenses, which are rigid (as opposed to being soft like a traditional contact lens) temporarily reshape the cornea and correct the astigmatism. These lenses require a longer adaptation period compared to normal contact lenses.
Laser Eye Surgery
Laser refractive surgery4 is a safe and effective way to correct astigmatism. These surgeries are heavily advertised as “LASIK”, “LASEK”, or “PRK”, which are names of various versions of the procedure.
During the surgery, the surgeon uses a powerful laser to correct the refractive error. The result of a successful procedure is the elimination of the need to use corrective lenses. In most cases, correction is long-term and often permanent.
In some cases, your eye may regress back into a state of refractive error. This can usually be corrected via a second procedure.