Astigmatism is when the cornea, the clear dome-shaped tissue on the front of the eye, is not perfectly round. Astigmatism is often compared to the shape of a football where one side is much more curved than that of the other side. The majority of people have some degree of astigmatism and it is rare to find someone with a perfectly round-shaped cornea.
What causes Astigmatism?
Astigmatism is genetic in nature and a natural variance among people like hair color or height. It is not a sight threatening condition and can easily be corrected with glasses, contacts, etc.
Symptoms of Astigmatism
Blurred vision, often in both eyes.
Glasses and contact lenses: Lenses are made to mirror the shape of the cornea since the differences in curvature will cause a need for different powers to see clearly. It is a common misconception that those with astigmatism cannot wear contact lenses. This is most surely not the case due to modern advancements in contact lens technology. However, it does not mean that some people may be more difficult to fit than others and therefore more lenses may need to be tried and different types used in order to find the best fit to provide optimal vision.
Orthokeratology: This is a process that incorporates the wear of specially made rigid gas permeable lenses to flatten the cornea at night. This allows the patient to be able to see clearly during the day without the use of any corrective lenses. Eye care professionals who fit specialty contact lenses can determine if you are a good candidate for orthokeratology lenses.
**It is important to note that these lenses were specifically designed to wear at night and have undergone FDA approval for such wear and in no way implies that all contacts can be worn as such.**
Laser Surgery: With lasers, it is possible to re-shape the cornea in a way that glasses or contacts will no longer be needed to see clearly. A good candidate needs to have a thick cornea and a mild prescription which may include some degree of astigmatism. The surgery is relatively fast and safe and often leaves the patient with great vision where the need for glasses would be minimal. To determine if you are a good candidate, contact your eye care professional.
Intraocular lens implants (IOLs): Intraocular lens implant surgery involves removing the current lens in the eye and replacing it with a new one. Since this requires invasive surgery into the eye, an IOL is not often the first choice for correcting astigmatism on its own with other safer options available. However, when the lens forms a cataract and causes blurred vision, this warrants the benefit of the surgery and the new lens that is used to replace it can be made to correct your astigmatism. The IOLs that correct for astigmatism are "toric" IOLs and cost slightly more than a spherical IOL since they are more difficult to manufacture.
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