What is Astigmatism?
As unpleasant as the word may sound, it’s not a deadly disorder and it is very common. Most people have some degree of astigmatism.
Astigmatism is simply an irregularly shaped cornea. Often, the comparison of astigmatism is likened to a football-shaped eye rather than a cylindrical, basketball-shaped eye. The irregular shape of the eye prevents light from being focused evenly at a single point thus resulting in distorted, blurry vision.
Often we are asked by patients, “Can LASIK treat astigmatism?” Absolutely. In fact, in 1999, Dr. Iskander himself had LASIK performed on his left eye with no refractive error, just astigmatism.
Astigmatism does not go away on its own, and may worsen with age. It is usually corrected by glasses, contacts or surgical intervention. Refractive surgery is an option once the vision is stable and unchanging. If astigmatism gradually worsens, it may be a condition called keratoconus.
How is Astigmatism Measured?
Astigmatism is measured in diopters. Anything less than 0.75D (diopters) is generally tolerated by patients. Up to 2D, you have a small degree of astigmatism. Between 2-4D you have a moderate amount of astigmatism. Above 4D is considered a significant amount of astigmatism.
- Cylindermeasures what degree of astigmatism, or the flatness or irregularity of the cornea.
- Axis is measured in degrees, and refers to where on the cornea the astigmatism is located. Axis ranges from 0 to 180 degrees.
How is Astigmatism Treated?
Unlike glasses and contacts that can superficially remedy astigmatism, laser vision correction surgery, such as LASIK, can permanently reshape the cornea and change the curvature of the eye thereby treating the astigmatism. LASIK is a great option for people with active lifestyles that don’t want to bother with contacts and glasses. Some people develop an intolerance to contact lenses with time and may develop corneal abrasions or even worse, corneal ulcers.
LASIK is not the only surgical intervention for astigmatism. For the elderly population that need cataract removal, Limbal Relaxing Incisions (LRI’s) and Toric Lenses are viable options.
LRI’s are miniscule manual incisions made by the surgeon around the corneal edge, called the limbus, to release tension on the cornea which causes distortion of vision. LRI’s are typically done during cataract removal procedures. LRI’s work well to treat up to 1.25D of astigmatism. They are cost effective and eliminate the need for glasses after cataract surgery.
However, for patients having higher amounts of astigmatism, toric lenses treat up to 4.75 with a greater level of predictability. While toric lenses are not a covered expense by insurance carriers, they are worth the value as they correct astigmatism and eliminate the inconvenience of glasses or contact lenses post cataract surgery.
On June 9th, 2020, Dr. Iskander was privileged to be the first ophthalmologist in San Antonio, and South Texas to implant the Johnson & Johnson multifocal toric Tecnis II lens. This much anticipated lens not only treats astigmatism, but the multifocal component helps people see near, intermediate and distance vision. Before this time, multifocal toric lenses correcting both astigmatism and presbyopia were used internationally and the United States awaited FDA approval.
Dr. Iskander is a fellowship-trained refractive surgeon with over 20 years surgical experience. He continuously researches and implements proven technology and surgical techniques to enhance the quality of lives of his patients to achieve their best corrected vision, independent of glasses and contacts, whenever possible.
Schedule your complimentary refractive consultation and discover your visual options. For your eyes…Don’t Compromise!