on Friday, February 17, 2012
While most people know about refractive errors of the eye such as nearsightedness or farsightedness, some eye care patients may ask, “What is astigmatism?” after their eye exam with an eye care practitioner. Astigmatism is a common refractive error that causes vision to be out of focus because the cornea is abnormally curved. While it is not known what causes astigmatism, it is typically present from birth and accompanied with other refractive errors such as nearsightedness or farsightedness. It can even occur after specific types of eye surgery such as cataract surgery.
Astigmatism is commonly diagnosed early in life, so it is important to make sure to be aware of the symptoms and schedule eye exams for younger children. Symptoms that can occur with astigmatism are blurred vision, headaches or eye strain after prolonged tasks such as reading. Astigmatism can be detected during a simple eye exam. The test for astigmatism that an eye practitioner uses is known as a retinoscopy. However, this test is slowly being replaced with an automated refraction.
Astigmatism can be treated in three ways: traditional glasses, surgery and contact lenses. While astigmatism had to be treated with hard contact lenses in the past, it can now be treated with soft toric lenses such as CooperVision’s Biofinity Toric line. CooperVision has created this toric lens for patients with astigmatism with two major benefits. It is made from silicon hydrogel which allows for more oxygen to pass through the eye. It is also our most stable toric design. When a patient with astigmatism wears a toric lens, it is essential that the lens is stable so that when the patient blinks, the lens doesn’t move too much. A toric lens needs to stay in place because there are two different powers in the lens versus a traditional spherical lens which is all one power. Toric lenses must remain in position on the patient’s eye for optimal visual acuity.
Remember, astigmatism is common and simple to detect. So if you want to learn more about astigmatism, ask your eye care professional. For more information on CooperVision’s Biofinity Toric lenses, visit our product page here .