Developmental timelines of Amblyopia

This table is taken and completed with information from the book “Applied Concepts in Vision Therapy” by Leonard Press.

“Critical period: birth to 6 months

• aggressive treatment required: critical to provide child with clear visual input
• lack of treatment results in legal blindness and nystagmus
• untreated infantile cataract is an extreme model of consequences of deprivation during early visual development. They exhibit dense, irreversible amblyopia with nystagmus
• infantile cataract is most treatable amblyogenic factor at this age
• other amblyogenic factors are maximally influential at this age

Sensitive period: 6 months to age 8

• upper age limit for onset of amblyopia
• aggressive treatment required
• lack of treatment results in visual impairment
• child remains vulnerable to the onset of amblyopia, however long term effects are less severe
• amblyopia can be reversed, assuming optimal patient compliance with therapy
• can recur if original amblyogenic factor has not been eliminated -> address binocular and refractive anomalies

Susceptible period: age 8 to age 18

• aggressive treatment indicated if patient is compliant
• if amblyogenic factor is still present, amblyopia can recur
• recurrences of amblyopia are possible as late as the teens
• the most common conditions that cause recurrence of amblyopia are unilateral strabismus and non-compliance with spectacle or contact lens wear in refractive amblyopia

Residual plasticity period: age 18 trhough adulthood

• treatment can be successful if patient compliant and prognosis optimal
• amblyopia not likely to recur even if amblyogenic factors still present”
  

Also read:
– What other visual anomalies do amblyopes have aside from reduced acuity and stereo vision?
– Redefining amblyopia as a disorder of vision development