How is astigmatism treated?

Persons with astigmatism have several options available to regain clear vision. They include:

• eyeglasses
• contact lenses
• orthokeratology
• laser and other refractive surgery procedures

Eyeglasses are a common form of correction for persons with astigmatism.

Eyeglasses are the primary choice of correction for persons with astigmatism. They will contain a special cylindrical lens prescription to compensate for the astigmatism. This provides for additional lens power in only specific meridians of the lens. An example of a prescription for astigmatism for one eye would be -1.00 -1.25 X 180. The middle number (-1.25) is the lens power for correction of the astigmatism. The "X 180" designates the placement (axis) of the lens power. The first number (-1.00) indicates that this prescription also includes a correction for nearsightedness in addition to astigmatism.

Generally, a single vision lens is prescribed to provide clear vision at all distances. However, for patients over about age 40 who have the condition called presbyopia, a bifocal or progressive addition lens may be needed. These provide different lens powers to see clearly in the distance and to focus effectively for near vision work.

A wide variety of lens types and frame designs are now available for patients of all ages. Eyeglasses are no longer just a medical device that provides needed vision correction. Eyeglass frames are available in a many shapes, sizes, colors and materials that not only allow for correction of vision, but also enhance appearance.

For some individuals, contact lenses can offer better vision than eyeglasses. They may provide clearer vision and a wider field of view. However, since contact lenses are worn directly on the eyes, they require regular cleaning and care to safeguard eye health.

Soft contact lenses conform to the shape of the eye, therefore standard soft lenses may not be effective in correcting astigmatism. However, special toric soft contact lenses are available to provide a correction for many types of astigmatism. Because rigid gas permeable contact lenses maintain their regular shape while on the cornea, they offer an effective way to compensate for the cornea’s irregular shape and improve vision for persons with astigmatism and other refractive errors.

Orthokeratology (Ortho-K) involves the fitting of a series of rigid contact lenses to reshape the cornea, the front outer cover of the eye. The contact lenses are worn for limited periods, such as overnight, and then removed. Persons with moderate amounts of astigmatism may be able to temporarily obtain clear vision without lenses for most of their daily activities. Orthokeratology does not permanently improve vision and if you stop wearing the retainer lenses, your vision may return to its original condition.

Astigmatism can also be corrected by reshaping the cornea using a highly focused laser beam of light. Two commonly used procedures are photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK).

PRK removes tissue from the superficial and inner layers of the cornea. LASIK does not remove tissue from the surface of the cornea, but only from its inner layer. To do this, a section of outer corneal surface is cut and folded back to expose the inner tissue. Then a laser is used to remove the precise amount of tissue needed and the flap of outer tissue is placed back in position to heal. Both procedures allow light to focus on the retina by altering the shape of the cornea.

Individuals with astigmatism have a wide range of options to correct their vision problem. In consultation with your optometrist, you can select the treatment that best meets your visual and lifestyle needs.