The eye movements of newborns are very inaccurate. They have fast and jerky movements, without the smooth coordination of normal visual fixation. During the first several weeks after birth, infants develop accurate, smooth pursuant eye movements and central fixation. A key developmental milestone for normal infants is the ability to fixate and accurately follow small objects by 2 to 3 months of age. Normal infants may occasionally show delayed visual maturation; however, poor fixation past 6 months of age is usually pathologic, and should be fully investigated with a complete ophthalmologic examination.
Visual acuity is just one accept of eye development. The alignment of the eyes also changes after birth. Eye alignment at birth is variable with approximately 70% of infants showing a small variable exotropia, 30% having essentially straight eyes, and esotropia is considered rare. Majority of normally developing infants have established proper alignment by 2-3 months of age. Therefore, the persistence of a strabismus after 2 months of age may indicate ocular pathology, and these patients should be referred for ophthalmologic evaluation.
|Birth to 2 months||Pupillary response
Jerky eye movements in response to visual stimuli
Poor sporadic fix and follow
Variable alignment: XT 70%, Straight 30%, ET rare
|2-6 months||Blink and responds to visual threat
Accurate fixation on visual target
Central fix and follow
Precise smooth eye movements
Properly aligned eyes (straight)
Accommodation, binocular fusion and stereopsis
|6 months – 2 years||Central fixation, accurate & smooth pursuit eye movements|
|3-4 years||VA 20/40 & not more than 2 line difference between the 2 eyes|
|5-6 years||VA 20/30 & not more than 2 line difference between the 2 eyes|
|7-9 years||VA 20/25 to 20/20 & not more than 2 line difference between the 2 eyes|
Any deviation from the above mentioned eye developmental milestones warrant an ophthalmologic evaluation.