Astigmatism is a normal vision problem due to an error in the shape of the cornea. With this, the lens of the eye or the cornea, which is the front surface of the eye, has an irregular curve which can change the way light passes, or refracts to your retina. This leads to blurry, fuzzy or distorted vision. Farsightedness and nearsightedness are two other problems given the way light passes to your retina. Farsightedness is called hyperopia whereas nearsightedness is called myopia.

Types

The two major types of astigmatism are corneal and lenticular. A corneal one happens when your cornea is misshapen. A lenticular one happens when your lens is misshapen.

Causes

It’s not well-known what causes astigmatism although genetics is a big factor. It’s often present at birth, but it may develop later in life. This astigmatism may also happen as a result of an injury to the eye or post eye surgery. It often occurs with either nearsightedness or farsightedness. Thus, it can occur in children and adults.

Symptoms

The symptoms of astigmatism may vary in each person. Also, some people don’t have any symptoms at all. The symptoms of this type of blurry vision include:

  • Blurry, deformed or fuzzy vision at all distances (nearby and far away)
  • Difficulty seeing at night
  • Eyestrain
  • Squinting
  • Eye irritation
  • Headaches

Go to a doctor if you have symptoms of astigmatism. Notably, some symptoms may also be due to other health or vision problems.

How is astigmatism diagnosed?

An optometrist or ophthalmologist diagnoses this through a thorough eye examination. There are various tests optometrists and ophthalmologists may employ during your eye examination to diagnose astigmatism. 

Treatments

Mild cases of astigmatism may not require treatment. Hence, your doctor may treat the one that causes vision problems by using one of the following methods:

Corrective lenses

Corrective eyeglasses and contact lenses prescribed by a doctor are the most common and least invasive treatments.

Orthokeratology (Ortho-K)

Orthokeratology (Ortho-K) is a treatment that uses rigid contact lenses to temporarily correct the irregular curvature of your cornea. You’ll wear rigid contact lenses for a limited period of time. You may wear them at the time of sleep and then take them off during the day. Although, some people have clear vision during the day without corrective lenses when undergoing Ortho-K. The benefits of Ortho-K are only present when using it. However, your vision will return to its previous state after stopping Ortho-K.

Surgery

Your doctor may recommend refractive surgery if you have a severe case. This type of surgery uses lasers or small knives to alter your cornea. Thus, this will permanently correct your astigmatism. The three common surgeries for astigmatism are laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), and radial keratotomy (RK). All surgeries carry some risks. Talk to your doctor about the risks and benefits before getting this surgery.

What is the long-term outlook?

Corrective lenses or surgery can generally bring back your vision to normal. However, there’s no known way to prevent astigmatism from coming up.