Farsightedness

Farsightedness causes blurry near vision due to an abnormality in the shape of the eye or its components.

Farsightedness or hyperopia is a refractive error that causes nearby objects to look blurry.

For normal vision, when light enters the eye:

• The cornea (the front of the eye) and the lens (an inner part of the eye that helps the eye focus) with curvature bend (refract) sharply focus the image directly on the surface of the retina (lining of the back of the eye containing light-sensing cells).
• The retina then sends a signal to the brain that allows seeing clearly.

Farsightedness occurs when the eye’s abnormally shaped cornea or lens focuses light behind the retina instead of on its surface. An individual with this condition may have one eye more farsighted than the other. People can typically see distant objects more clearly than close ones (reading or using a computer becomes difficult).

Farsightedness is a common vision abnormality or an eye-focusing disorder.

The cause of farsightedness is either of the following:

• The eye is not bending light properly
• Abnormal shape of the cornea or lens
• The eyeball could be shorter than normal (from front to back)
• The cornea has too little curvature

These problems make the eye focus light behind the retina, instead of on it, making nearby objects look blurry.

Hereditary factors (being born with the problem) and having other farsighted family members (first-degree relatives) can increase the risk significantly.

Most children with hyperopia do not have symptoms because of the flexibility of the lens, which makes accommodation (changing focus between distances) easier.

Common signs of hyperopia include:

• Difficulty concentrating
• Trouble seeing close things
• Excess tearing
• Squinting
• Frequent blinking
• Difficulty keeping a clear focus on near objects
• Eye strain
• Fatigue
• Problems with hand-eye coordination
• Headache after close work or reading
• Aching or burning eyes
• Irritability or nervousness after sustained concentration

Other refractive errors include:

• Myopia (nearsightedness): A blurry appearance for distant objects occurring when the eyeball is longer than normal or the cornea is curved steeply.
• Astigmatism: Blurred distance and near visions occur when the cornea or lens is curved more steeply in one direction than it is in another.

Apart from a refraction assessment and a routine eye health examination, the ophthalmologist (eye specialist) checks for farsightedness by conducting a comprehensive eye examination.

For younger children, the ophthalmologist may use a retinoscope to measure where light reaches inside the eye.

In mild cases of farsightedness, the most common treatments are eyeglasses or contact lenses. In moderate cases, a doctor often prescribes eyeglasses or contact lenses that alter the way the light enters the eyes, allowing the person to see close objects.

In severe cases, doctors can use surgery to treat farsightedness in adults. This surgery changes the shape of the cornea so that it can focus light optimally.

Refractive surgery

• Refractive laser surgery: A laser reshapes the cornea to adjust the light traveling through it.
  • Laser in-situ keratomileusis
  • Photorefractive keratectomy
• Refractive lens exchange: The natural lens is replaced with an intraocular lens (artificial lens) that helps correct farsightedness.

Children with severe farsightedness are at an increased risk of developing other eye conditions, such as amblyopia (lazy eye) and strabismus (eyes that are misaligned). Both conditions can lead to significant visual impairment.

Older adults may develop presbyopia (difficulty seeing things closely). Presbyopia occurs due to thickening and decreased flexibility of the lens of the eye as the person ages and the muscles surrounding the lens weaken.