Abstract
Purpose: :
To report the prevalence of amblyopia in right or left eyes of children 3 to <18 years of age.
Methods: :
The Pediatric Eye Disease Investigator Group has conducted 9 prospective randomized treatment trials of amblyopia in children between 3 and <18 years of age across North America. 2694 children were enrolled with visual acuity in the amblyopic eye, 20/40 to 20/400. We compared the proportion of right and left eyes affected by amblyopia and examined the influence of baseline and demographic factors on the distribution.
Results: :
Overall, left eyes were more frequently affected by amblyopia than right eyes (56.6% vs 43.4%, p<0.001). This association was independent of age (p=0.46), race (p=0.28), and severity of amblyopic eye visual acuity (p=0.27), but was related to anisometropia as the underlying cause of amblyopia (p<0.001). Among patients with cause of amblyopia defined as anisometropia alone or combined mechanism (anisometropia and strabismus), left eyes were more frequently affected by amblyopia than right eyes (59.5% vs 40.5%, p<0.001). Among patients with cause of amblyopia defined as strabismus alone 50.3% were affected by amblyopia in the left eye compared to 49.7% in the right (p=0.89).
Conclusions: :
Anisometropia (with or without strabismus) was strongly associated with the predominance of amblyopia in left eyes. Further study is needed to determine whether there are factors which predispose to the development of greater hypermetropia in left eyes.
Clinical Trial: :
www.clinicaltrials.gov NCT00001864
Keywords: amblyopia • strabismus • refractive error development