Natural History of Accommodative Esotropia with a High AC/A Ratio
Margaret M. Reynolds; Nancy N. Diehl; Brian G. Mohney
Rochester, Minnesota USA
Introduction: To report the natural history of high accommodative convergence/accommodation (AC/A) ratio among a population-based cohort of children with accommodative esotropia (AET).
Methods: The medical records of all patients < 19 years diagnosed with accommodative esotropia with a high AC/A ratio from January 1, 1975, through December 31, 2004, were retrospectively reviewed.
Results: A total of 517 patients were diagnosed with AET during the 30-year study period, of which 106 (20.5%) had a high AC/A ratio. Of the 93 (87.7%) high AC/A patients managed with bifocals, 50 (53.8%) were able to discontinue their use after a mean of 58.7 (range, 0 to 229) months. The Kaplan-Meier rate of discontinuing bifocals was 24.5% at 3 years, 36.4% at 5 years and 61.4% at 10 years. Patients who did discontinue bifocals were significantly more likely to have had surgery (44% vs. 18.6%, p=0.009) than those who did not discontinue bifocals. The high AC/A patients managed with bifocals were slightly less likely to undergo strabismus surgery compared to those managed without bifocals (p=0.13).
Discussion: The use of bifocals among esotropic children with high AC/A ratio is relatively temporary for most patients and not associated with an increased need for surgery.
Conclusion: In this cohort of children with high AC/A accommodative ET, bifocal use was discontinued in most children within 10 years, and more commonly among those who underwent strabismus surgery. The use of bifocals, however, did not increase the likelihood of undergoing surgery compared to those who did not use them.
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