Ocular And Systemic Associations of Against-the-rule Astigmatism in Children Presenting to a Tertiary Referral Hospital

1. Peter Kim
2. Salma KCRai
3. Maryam Aroichane
4. Jane A. Gardiner
5. Christopher J. Lyons

British Columbia Children's Hospital, Vancouver, Canada

Purpose: To determine the ocular and systemic associations of against-the-rule (ATR) astigmatism in children presenting to a tertiary referral hospital.

Design: Case control study

Methods: Retrospective study of patients with ATR astigmatism on cycloplegic refraction presenting to the British Columbia Children's Hospital from 1995 to 2009. Control subjects were randomly selected from the clinical records.

Results: A total of 19405 clinical records were reviewed of which 281 subjects (1.4%) with ATR astigmatism were identified. 281 control subjects were randomly selected. The mean logMAR visual acuities in the ATR astigmatism and control groups were 0.2 (20/32) and 0.11 (20/26) respectively (p<0.0001). There was a myopic tendency in the ATR astigmatism group (p=0.0007). High myopia (p=0.006) and high astigmatism (p=0.008) were more common in patients with ATR astigmatism.

Significant systemic associations for ATR astigmatism included global developmental delay (p<0.0001), prematurity (p=0.001), hearing impairment (p=0.001), genetic/syndromal disorders (p=0.001), and neurological abnormalities (p=0.003). Ocular colobomas (p=0.033) and microphthalmia (p=0.025) were the only significant ocular associations.

Conclusions: ATR astigmatism was an uncommon finding in this clinical pediatric population. ATR astigmatism was found to have numerous ocular and systemic associations, in particular, global developmental delay. Clinicians should note the axis as well as magnitude of astigmatism on cycloplegic refraction.