Abstract
Purpose :
To understand factors related to longitudinal change refraction and biometry of children with hyperopia: do they reach emmetropia?
Methods :
In the Sydney Myopia Study and Sydney Adolescent Vascular Eye Study, 892 of the younger cohort aged 6 years at baseline and 1211 of the older cohort aged 12, were followed up 5 years later. All children had a comprehensive eye examination including cycloplegic (1% cyclopentolate) autorefraction (RK-F1, Canon, Japan). Spherical equivalent refraction (SER) was calculated and 92 younger and 32 older children with significant hyperopia ≥+2 diopters (D) were identified. Ocular biometry was measured by IOLMaster (Carl Ziess Meditec, Germany) and the axial length to corneal radius ratio (AL/CR) calculated.
Results :
Of the younger cohort 78% and 47% of the older cohort had a SER change of ≥-0.50D and only 3 younger children had a 5 year change ≥-2.50D. None of the older cohort reached emmetropia and 75% remained significantly hyperopic. One younger child became emmetropic and another mildly myopic, 57.7% were mildly hyperopic and 40.2% remained significantly hyperopic. Those with hyperopia <2.00D at follow-up were significantly less hyperopic at baseline (younger cohort p<.001, older cohort p=.007). Conversely for those whose baseline SER was ≥3.50D, 55% in the younger and 81.8% in the older cohort remained significantly hyperopic (r=.643, p<.001 and r=.724, p<.001, respectively). The younger children whose decrease in SER was ≥0.50D were significantly less hyperopic at baseline (mean= 2.75D) compared to those who had negligible decrease in SER (mean= 3.33D, p=.038) but this relationship was not significant in the older children. Overall, the younger cohort had a greater mean refractive change (mean= -0.80D) than the older cohort (mean= -0.43D, p=.048). Similarly, decrease in SER (p<.001), increase in axial length (p=.001) and AL/CR (p<.001) were significantly greater in younger children with a SER <2.00D at follow-up than those who remained significantly hyperopic. In the older cohort there was a similar trend but only decrease in SER was significant for children who had an SER <2.00D at follow-up (p=.007).
Conclusions :
The majority of children with significant hyperopia remained hyperopic. This was particularly evident for those who had high hyperopia at baseline. For the older children, reduction in hyperopic refractive error was less evident possibly due to slowing of axial elongation with age.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.