Refractive development in children with Down's syndrome: a population based, longitudinal study

Area of Science:

• Ophthalmology
• Genetics
• Developmental Biology

Background:

• Down syndrome is associated with a high prevalence of refractive errors, including hypermetropia and astigmatism.
• Understanding the longitudinal refractive development in children with Down syndrome is crucial for early intervention and management.

Purpose of the Study:

• To longitudinally investigate refractive development in children with Down syndrome.
• To identify correlations between refractive status, accommodation, and astigmatism in this population.

Main Methods:

• A cohort of 60 children with Down syndrome underwent repeated retinoscopies under cycloplegia for over two years.
• Accommodation was assessed using dynamic retinoscopy.
• Refractive categories included stable hypermetropia, increasing hypermetropia (hypermetropic shift), and decreasing hypermetropia/myopic shift.

Main Results:

• Three refractive categories were observed: stable hypermetropia (n=34), increasing hypermetropia (n=11), and decreasing hypermetropia/myopic shift (n=9).
• Accommodation weakness was present in 55% of children and was less frequent in stable, low-grade hypermetropia.
• Astigmatism (>/=1.0 D) was found in 57% of eyes, predominantly with-the-rule, and oblique astigmatism showed specific axis directions for right and left eyes.

Conclusions:

• Stable, low-grade hypermetropia in children with Down syndrome is significantly correlated with normal accommodation.
• Accommodation weakness may play an etiological role in the high frequency of refractive errors observed.
• The specific axis direction in oblique astigmatism suggests mechanical factors related to palpebral fissures may contribute to its development.