What Is Astigmatism and How Can It Be Corrected?

DR. AJAY SHARMA December 7, 2023

Astigmatism is a common type of refractive error. It is a medical term that means some parts of your eye, especially the cornea or the clear front part of the eyeball, are more curved than they should be. An eyeball should be shaped like a perfectly round ball. This altered eye shape can make your vision blurry.

It is expected to have astigmatism along with farsightedness (hyperopia) or nearsightedness (myopia). These three eye conditions are referred to as refractive errors because they include how your eyes bend (refract) light. An eye doctor can easily treat astigmatism with contact lenses such as glasses, contacts, or surgery.

What are the Types of Astigmatism?

Astigmatism, known as corneal astigmatism by eye care specialists, is usually caused by the cornea’s irregular shape.

You can also have lenticular astigmatism, where the lens in your eye is distinctive. Cataracts often cause lenticular astigmatism.

Some people can have both corneal and lenticular astigmatism.

Who can be affected by Astigmatism?

Anyone can develop astigmatism at any point in their life. Some people are born with it, but many develop it as children or young adults. Some people may develop it after an eye injury, trauma, or surgery. Among three people, 1 has astigmatism. It is widespread and can get better or worse over time.

What are the Symptoms and Causes?

• Symptoms
  One of the common symptoms of astigmatism is blurred vision. It also makes it hard to see details of an object, like letters on a road sign in the distance or the words printed on a menu in front of you. Other symptoms include:
  • Seeing a glare or halos around lights
  • Squinting to see clearly
  • Headaches
  • Fatigue
  • Eye strain

  Even though some people are experiencing symptoms, they are unaware of anything wrong with their vision. So, it will be better to consult an eye care provider if you notice any change in your vision, such as itching, strain, or frequent headaches.

• Causes
  Astigmatism is generally hereditary, which means it is a condition that can be passed down by the biological parents to their children or have a family history of astigmatism. It also can be caused by your eyelids putting too much pressure on your cornea.Generally, it is not caused by any health conditions; however, some conditions that can cause astigmatism include
  • Eye injuries
  • Keratoconus
  • Complications after eye surgery

Can It Be Corrected?

Yes, wearing glasses or contact lenses can correct your vision, but it can’t change the shape of your eye. Vision correction surgeries (such as LASIK eye surgery and photorefractive keratectomy or PRK eye surgery) use lasers to fix vision problems. These surgeries help to reduce astigmatism and improve your vision.

Whether you receive a prescription for glasses or contacts, cylindrical lenses can effectively correct your astigmatism, unlike spherical lenses. These lenses work by refracting light onto a singular point on the retina, providing proper correction for astigmatism.
Various eye vision treatment options to correct astigmatism are discussed below. Still, the primary key point is that astigmatism correction parallels other refractive errors achievable through glasses, contacts, or surgical interventions.

1. Prescription Glasses
   Wearing eyeglasses is one of the effective ways to treat astigmatism. After diagnosing your astigmatism, your doctor can determine your eye prescription and fit lenses into the frames of your choice.  People with severe astigmatism may be better suited for eyeglasses instead of contacts.

2. Specialty Contact Lenses
   Similar to glasses, contact lenses can correct astigmatism, but they rest directly on the surface of your eye. Various types of lenses are available to treat astigmatism, including soft lenses, gas-permeable contact lenses, and hybrid lenses.

• Soft Contact Lens: Toric lenses, a specific soft contact designed for astigmatism, are weighted to ensure proper eye alignment. They incorporate varying powers in different meridians (the imaginary perpendicular lines in your eye) to effectively correct your vision.
• Gas Permeable Contact Lens: Also referred to as RGP or GP contact lenses, this lens type is more rigid to maintain its shape on the eye. While rigid lenses can contribute to sharper vision, the fit and sensation may not suit everyone.
• Hybrid Contact Lenses: These lenses utilize rigid gas permeable lens material for the center of the contact, surrounded by a soft material.

3. Refractive Surgery
   Laser surgery is a procedure that alters the cornea to correct refractive errors, and there are two primary options: LASIK and photorefractive keratectomy (PRK). The critical distinction between LASIK and PRK lies in how eye surgeons access the cornea.

• LASIK surgery employs an ultrafast femtosecond laser, utilizing small pulses of light to create a flap folded back during the procedure so the ophthalmologist can access the cornea. Subsequently, an excimer laser reshapes the cornea, smoothing out distortions to eliminate refractive errors.
• PRK surgery involves removing the outer surface of the cornea, known as the epithelium, before using a laser to reshape the inner cornea. The epithelium naturally regrows after the surgery. PRK is an alternative to LASIK, particularly suitable for individuals with dry eyes or thin corneas.