News and Events Eye Care Center Appointments

Refractive Errors

Refractive errors are common vision issues affecting how light enters the eye. They can result in blurred or distorted vision and often require eyeglasses, contacts, or laser vision therapy such as LASIK to restore clarity.

What Are Refractive Errors?

Refractive errors are common vision problems caused by an imperfection in the shape of the eye, which prevents light from focusing directly on the retina. The retina is the tissue at the back of the eye that transmits signals to the brain, allowing you to see. When the light doesn’t focus properly on the retina, it can result in blurred or distorted vision.

Astigmatism (Blurry Vision)

Astigmatism occurs when the cornea (the front part of the eye) or the lens (located inside the eye) is irregular. Because light focuses unevenly, this condition leads to blurred or distorted vision at any distance.

Presbyopia (Old Eyes)

Presbyopia is an age-related condition in which the eye’s lens loses its flexibility over time. This makes focusing on close-up objects difficult and requires reading glasses. It usually becomes noticeable around 40 and is a normal aging process.

Hyperopia (Farsightedness)

Hyperopia occurs when the eyeball is too short or the cornea has too slight curvature. This causes light to focus behind the retina rather than directly on it. Close-up objects appear blurry, while distant objects may be seen more clearly.

Myopia (Nearsightedness)

Myopia is the opposite of hyperopia. In this condition, the eyeball is too long, or the cornea is too curved. As a result, light focuses in front of the retina, causing distant objects to appear blurry. In contrast, close-up objects are seen more clearly.

Know the Difference

Both presbyopia and hyperopia make it challenging to see things up close. Still, the difference is in how and when they occur. Presbyopia is an age-related condition that causes near-vision loss due to the hardening of the eye’s lens, typically arising in patients over 40. Hyperopia is due to the eyeball’s shape, which can be present from birth or worsen over time.

Symptoms of Refractive Errors

Refractive errors are caused by several factors, including genetics, eye disease or injury, surgery, or even environmental conditions like reading in low light or too much screen time. Common symptoms of refractive errors include:


  • Eyestrain
  • Squinting
  • Headaches
  • Eye Discomfort
  • Difficulty Seeing in Low Light
  • Difficulty Seeing Close Objects (Farsightedness and Presbyopia)
  • Difficulty Seeing Distant Objects (Nearsightedness)
    Blurry Vision (Astigmatism)

How Are Refractive Errors Treated?

Refractive errors are common and can often be corrected with eyeglasses, contact lenses, or refractive surgery.

Eyeglasses & Contacts

Prescription eyeglasses and contacts are the most common and effective methods to correct refractive errors. Specifically designed lenses compensate for issues caused by eye shape irregularities. They are available in different types and strengths depending on the condition of the eye.


LASIK, or laser-assisted in situ keratomileusis, is a popular surgical procedure for correcting refractive errors. During LASIK, your surgeon uses a laser to reshape the cornea, altering the curvature to improve the eye’s ability to focus.

Laser Surgery

In addition to LASIK, other laser surgery techniques may be employed to correct refractive errors, including photorefractive keratectomy (PRK), which is similar to LASIK and involves reshaping the cornea using a laser.

Learn More

At Chicago Eye Surgeons, we understand the significance of your vision. We are committed to providing advanced eye care and vision correction treatments to enhance your quality of life. If you have less-than-perfect vision, schedule an eye exam and discover your options today.