Vision Training

Vision training helps those with a weakness in the coordination of the two eyes. Treatment for coordination problems typically requires a series of vision training exercises. Vision training may also benefit children with “lazy eyes”. Many of these vision training exercises can be done at home.
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Children Visual Problems

Refractive errors, strabismus and amblyopia are the common visual problems in children

Refractive Errors

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Refractive errors occur when there is a mismatch between the length of the eyeball and these focusing organs so that vision becomes blurry. Hyperopia, Myopia and Astigmatism are common types of refractive error in children.
1. Hyperopia
Hyperopia refers to the condition when the eyeball is too short that light rays from a distance object focus behind the retina leading to blurry vision. Most infants are born with hyperopic eyes. Hong Kong infants was found to have around +2.50D of hyperopia by the age of 11 weeks and reduced rapidly to less than +1.00D by the age of 9 months.
2. Myopia
Myopia refers to the condition when the eyeball is too long that light rays from a distance object focus in front of the retina leading to blurry vision. The prevalence of myopia among Hong Kong Chinese children increased from 18% at 6 years old to around 60% at 12 years old. Most of the increase in myopia was noted between 6 to 10 years old.
3. Astigmatism
Astigmatism refers to the condition when the curvature of the cornea is unequal at different meridians. Light rays passing through such cornea focuses unevenly on the retina leading to blurry vision. More than half of the infants are born with above -0.75D of astigmatism. One-fourth of infants with astigmatism of -2.00D or more by age of 10 weeks. The astigmatism reduced rapidly with age and leaving only 2% have such high amount of astigmatism by age of 10 months. Although it is very common for infants to born with some degree of refractive error, abnormally high refractive errors if left untreated can lead to long term negative impacts including amblyopia and strabismus.


Strabismus HD
Strabismus is another common visual problem in children which causes may include eye muscle imbalance, significant refractive errors like high degree of long-sightedness or a big difference in refractive error between two eyes. Untreated strabismus may cause:
  • Amblyopia
  • Occasional double vision
  • Hindrance to the development of depth perception
  • Poor eye-hand coordination
  • Eyestrain or headaches when reading
With the increasing demand on visual ability for schoolwork, symptoms of strabismus may be more noticeable in schoolchildren. Treatment of strabismus may include wearing spectacles, prism lenses, vision training or eye surgery.

Fitting procedures of

eye patching
Lazy eye often occurs in children who has significant uncorrected refractive errors, anisometropia and strabismus. No clear image to stimulate visual area of the brain will result in adverse visual development of eye or eyes. Amblyopia affects 2.67% preschool children in Hong Kong. Conditions that cause amblyopia include:
  • Improper correction of refractive errors
  • Anisometropia
  • Strabismus
  • Congenital cataract
  • Drooping eyelids
These conditions may be coexist.
Amblyopia is not only a matter of reduced visual acuity, but also results in:
  • Poorer accommodative response
  • Reduced contrast sensitivity
  • Poorer fine motor and visuomotor skill such as grasping objects, walking, driving and reading
Amblyopia may be treated with wearing spectacles, patching and/or vision training. However, the effectiveness of vision improvement significantly reduced in children whom are older than 8 years of age. Vision has been developed very rapidly during the first 8 years; visual problems may affect their development in academic, social and athletic areas. Early detection, prevention and treatment are the key factors for preventing the life-long ocular disorders for our children.
(Information provided by The Hong Kong Polytechnic University Optometry Clinic)