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Published on: March 24, 2020
Neonatal ocular misalignments reflect vergence development but rarely become esotropia
1Orthoptic Department, Royal Berkshire Hospital, London, UK. a.m.harwood@reading.ac.uk
Insights
Neonatal misalignment (NMs) in infants often indicates a developing vergence system, appearing in the first two months. Frequent NMs may correlate with later achievement of constant alignment but earlier convergence attempts.
Area of Science:
- Ophthalmology and Vision Science
- Developmental Pediatrics
- Orthoptics
Background:
- Study followed 214 infants of orthoptist mothers for up to 15 years.
- Investigated relationship between neonatal misalignment (NMs) and convergence development.
- Examined NMs in context of later childhood ocular abnormalities.
Purpose of the Study:
- To characterize neonatal misalignment (NMs) behavior in infants.
- To correlate NM patterns with the onset of convergence and prism response.
- To assess the link between early NMs and subsequent ocular development.
Main Methods:
- Prospective postal survey design.
- Orthoptist mothers observed and reported on their own infants' ocular behavior.
- Data collected on alignment, visual development, and ocular abnormalities during early life.
Main Results:
- Confirmed known characteristics of NMs.
- More frequent NMs were associated with longer misalignment duration (p <0.01) and delayed constant alignment (p <0.001).
- Infants with frequent NMs showed earlier first convergence attempts (p = 0.03), with peak NM frequency near convergence onset (p = 0.0002).
Conclusions:
- Neonatal misalignments (NMs) occur within the first two months of life.
- NMs typically signify a normally developing vergence system and early convergence attempts.
- Infantile esotropia is clinically indistinguishable from frequent NMs before two months of age.
Background:
214 orthoptists' infants have been followed for up to 15 years, relating neonatal misalignment (NMs) behaviour to onset of convergence and 20 Delta base out prism response, and also to later childhood ocular abnormalities.
Methods:
In a prospective postal survey, orthoptist mothers observed their own infants during the first months of life and regularly reported ocular behaviour and alignment, visual development, and any subsequent ocular abnormalities.
Results:
Results confirm previously reported characteristics of NMs. Infants who were misaligned more frequently were misaligned for longer periods (p <0.01) and were later to achieve constant alignment (p <0.001) but were earlier to attempt first convergence (p = 0.03). Maximum NM frequency was usually found at or before the onset of first convergence (p = 0.0002).
Conclusions:
NMs occur in the first 2 months of life and usually reflect a normally developing vergence system. They appear to represent early attempts at convergence to near targets. Emerging infantile esotropia is indistinguishable from frequent NMs before 2 months.
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