Visual impairment (VI) refers to a significant functional loss of vision that cannot be corrected by medication, surgical operation, or ordinary optical lenses such as spectacles.

Visual impairment can be classified into three levels:

Mild VI:

  • Can read relatively larger characters
  • No difficulty in identifying shapes, colours and brightness contrasts

Moderate VI:

  • Can tell shapes and colours of objects and can distinguish between brightness and darkness
  • Can only read characters with larger size and broader strokes

Severe VI:

  • Can only distinguish more obvious changes in brightness and darkness
  • May not see anything (completely blind)Symptoms of visual impairmentDuring infancy:
    • Lack of eye contact
    • No blinking to bright light
    • Do not look at his/her hands
    • Do not visually follow moving objects in front of his/her face
    • Slow response to voiceless toys or parents’ faces; respond only to sound
    • No imitation of others’ expressions and actions
    • Do not actively reach out for his/her favorite toys
    • Fear of gross motor activities, such as crawling

     During early childhood:

    • Often keep his/her head down; lack eye contact with others
    • Limited facial expression and body language
    • Tend to hold objects very close to the eyes when looking at them
    • Abnormal responses to bright light (gazing at light excessively or trying to avoid it)
    • Often bump into objects or fall over, and get confused with directions
    • Search for his/her way using hands
    • May press on eyeballs with fingers
    • Jerky movements of the eyeballs

    Causes of visual impairment

    • Infections during pregnancy, e.g. rubella infection
    • Congenital eye diseases, e.g. congenital cataract
    • Factors during delivery, e.g. asphyxia, retinal problems of prematurity
    • Acquired eye diseases, e.g. corneal infection, tumour of eyeball


    early assessment and treatment

    Parents can understand their child’s developmental problems at an early stage and provide appropriate and timely support to maximize the potentials of their child

    • Visual impairment or even blindness can be avoided if eye diseases such as glaucoma and cataract are detected and managed at an early stage
    • Secondary problems on areas including emotion, behaviour and learning can be prevented
    1. Basic principles for training children with visual impairment

    Overall Cognition

    • Encourage children with VI to touch physical objects more frequently and use simple verbal descriptions, to strengthen conceptual understanding of objects and events

    Sensory Training

    • Strengthen sensory training on senses other than vision, e.g. the sense of touch,hearing, smell and taste

    Residual Vision

    • Assist children with VI in protecting and making good use of their residual vision

    Personal Experience

    • Encourage children with VI to participate actively in activities so as to enrich life experience. Avoid helping them on everything and allow them learn independently as appropriate