Effects on Vision

Girl being fitted for glasses
Of all the problems affecting premature babies, vision problems are among the most common. Although some premature babies may end up blind or functionally blind, it is a rare event. For most, vision problems are correctable with glasses or contact lenses.

Retinopathy of prematurity (ROP), a condition in which the blood vessels in the eye grow abnormally, can cause sometimes vision problems that have lasting effects. While many babies with ROP will go on to have excellent or near excellent vision, a severe case of ROP can cause the retina to detach or partially detach, which will result in profound and probably permanent vision loss.

Milder cases of ROP usually resolve themselves. Severe cases may require laser or other forms of surgery to correct vision problems.

Some cases of ROP may leave a child with conditions reducing vision either in the form of sharpness of vision, known as acuity, or a visual field deficit affecting the ability to see within a full field of view. Although not only caused by ROP, these conditions may include:

  • Short-sightedness, also called myopia. Having this condition means that the eye cannot focus on distant objects. Many adults have this condition, which is usually corrected with glasses. It can sometimes be corrected, or diminished, with laser surgery when older.
  • Strabismus. This condition is sometimes referred to as being “cross eyed.” One or both eyes may turn in or out. Sometimes this eye turn can be corrected with corrective glasses. If this is not possible, surgery on the eye muscles may be performed to achieve eye alignment. 
  • Astigmatism. This is a condition where the cornea is asymmetrical, which makes focusing difficult. Astigmatism is very common; many people are born with astigmatism and have it to some degree without significant vision problems. The condition also appears with either short- or long-sightedness. Special lenses may be required to help correct the problem.

All premature babies should have their eyes checked regularly. Parents can be on the look out for eye problems. Common signs of eye problems include:

  • not being able to follow an object at six weeks corrected age and beyond
  • a constant jiggling movement of the eyes
  • frequent eye crossing beyond three months corrected age
  • not blinking when flash photography is used
  • an aversion to normal lighting

With regular check-ups and parents on the look out for trouble in between medical visits, many vision problems can be treated. It is important to identify these problems early as some of these conditions are best treated while the child is very young. Indeed, some of these conditions have a “window of opportunity” in that they can only be effectively treated when the patient is young.

Nasrin Najm-Tehrani, MD, MB BCh, MSc, FRCS Ed (Ophthalmology)