Journal List > J Korean Ophthalmol Soc > v.55(2) > 1009888

J Korean Ophthalmol Soc. 2014 Feb;55(2):267-270. Korean.
Published online February 17, 2014.  https://doi.org/10.3341/jkos.2014.55.2.267
Copyright © 2014 The Korean Ophthalmological Society
The Ratio of Accommodative-Convergence to Accommodation in Patients with Nonrefractive Accommodative Esotropia
Rebecca Kim, MD and Se Youp Lee, MD, PhD
Department of Ophthalmology, Keimyung University School of Medicine, Daegu, Korea.

Address reprint requests to Se Youp Lee, MD, PhD. Department of Ophthalmology, Keimyung University Dongsan Medical Center, #56 Dalseong-ro, Jung-gu, Daegu 700-712, Korea. Tel: 82-53-250-8400, Fax: 82-53-250-7705, Email: lsy3379@dsmc.or.kr
Received March 29, 2013; Revised June 25, 2013; Accepted December 20, 2013.

Abstract

Purpose

To measure the ratio of accommodative-convergence to accommodation (AC/A ratio) in patients with nonrefractive accommodative esotropia in comparison to refractive accommodative esotropia and normal groups.

Methods

A total of 43 subjects were divided into 3 groups: the nonrefractive accommodative esotropia group (group 1), the refractive accommodative esotropia group (group 2) and the normal group (group 3). Age, sex, age of onset, and refractive errors were recorded. The deviation angle was measured near and at distance by using a prism cover test. The AC/A ratio was calculated using a gradient method.

Results

Refractive errors were 2.3 ± 1.7 D (OD) and 2.4 ± 2.1 D (OS) in group 1, 4.8 ± 0.9 D (OD) and 4.6 ± 1.1 D (OS) in group 2, and -0.3 ± 1.5 D (OD) and -0.5 ± 1.5 D (OS) in group 3. Group 2 had higher mean refractive errors than groups 1 and 3, while the difference in refractive error between group 1 and group 3 was not statistically significant. The AC/A ratio was 5.5 in group 1, 2.1 in group 2 and 2.2 in group 3; there was no significant difference between groups 2 and 3, while group 1 had a significantly higher AC/A ratio than both of these groups.

Conclusions

AC/A ratio in patients with nonrefractive accommodative esotropia is higher than that of refractive accommodative esotropia or normal children. It could be used for bifocal lens as non-surgical treatment.

Keywords: Nonrefractive accommodative esotropia; Ratio of accommodative-convergence to accommodation; Refractive accommodative esotropia

Tables


Table 1
Subject and subgroup demographics
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Table 2
Comparison of refraction error and AC/A ratio in each group
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Table 3
Comparison of esodeviation angle in group 1 and group 2
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Notes

This study was presented as a narration at the 108th Annual Meeting of the Korean Ophthalmological Society 2012.

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