What is Astigmatism?
Astigmatism is a common vision disorder that causes distorted and blurred eyesight. It is a refractive error and occurs when the cornea or the lens have irregularities in shape or curvature. When the refractive error is due to the cornea, is called corneal astigmatism; when it is due to the lens it is called lenticular astigmatism.
When light enters the eye, it refracts, or bends. The cornea–the transparent layer that covers the front of the eye–and the lens are responsible for focusing light precisely on to the retina. The retina then converts the light into signals, which are transmitted to the brain via the optic nerve. The brain interprets these signals in order to form an image. If the cornea or lens are imperfectly shaped, the incoming light will bend more in one direction or another, causing blurred vision.
In most cases, astigmatism is an eye condition that is present at birth and its presence is related to genetics. Sometimes astigmatism can arise due to an injury or trauma to the eye. Other common refractive errors are nearsightedness (myopia) and farsightedness (hyperopia).
Symptoms & Diagnosis of Astigmatism
The common symptoms of astigmatism include:
- Images are stretched out, blurry or distorted
- Difficulty with night vision
To diagnose astigmatism, Dr. Semaan will conduct a comprehensive eye examination, which includes:
- Visual acuity test: an eye chart test that evaluates clarity of vision
- Refraction test: a test where different lenses are placed in front of your eyes to determine the appropriate strength for corrective eyewear
- Keratometry: a test to measure the curvature of the cornea
Astigmatism can be mild enough that an individual does not notice any significant effect on the eyesight. In cases where vision is markedly distorted, corrective measures can be taken.
Astigmatism is most commonly treated with corrective lenses (glasses or contacts). Prescription eyewear is a straight-forward solution that can make an immediate difference in the quality of vision.
Astigmatism can also be corrected with refractive surgery, or laser eye surgery. Refractive surgery is a safe and effective procedure that permanently modifies the shape of the cornea. Refractive surgery is a popular option for patients who would like to have clear vision without having to use glasses or contacts.
Your Consultation with Dr. Semaan, Orange County, CA
If you have been diagnosed with astigmatism, it is important to have your eyes checked regularly for any changes in vision. If you are due for a routine eye exam visit, Dr. Semaan of Beach Eye Medical Group, Huntington Beach. Contact the Beach Eye office to make an appointment.