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Lee, Park, Lee, and Lee: A Ratio of Accommodative-Convergence to Accommodation in Patients With Refractive Accommodative Esotropia
Original Article

J Korean Ophthalmol Soc 2010;51(7):988-991.

Published online: 31 August 2010

DOI: https://doi.org/10.3341/jkos.2010.51.7.988

A Ratio of Accommodative-Convergence to Accommodation in Patients With Refractive Accommodative Esotropia

Dong-Cheol Lee, MD1, Ji-Hyun Park, MD3, Young-Chun Lee, MD2, Se-Youp Lee, MD1

1Department of Ophthalmology, Keimyung University School of Medicine, Daegu, Korea

2Department of Ophthalmology, The Catholic University of Korea School of Medicine, Seoul, Korea

3Department of Ophthalmology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea

Address reprint requests to Se-Youp Lee, MD, Department of Ophthalmology, Keimyung University Dongsan Medical Center #194 Dongsan-dong, Jung-gu, Daegu 700-712, Korea Tel: 82-53-250-7720, 7707, Fax: 82-53-250-7705, E-mail: lsy3379@dsmc.or.kr

Received 19 February 2010       Accepted 18 May 2010

Copyright © 2010 Korean Ophthalmological Society

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Purpose

The goals of the present study were to measure a ratio of accommodative-convergence to accommodation (AC/A ratio) in child patients with refractive accommodative esotropia (RAET) and to compare it to the ratio in normal children.

Methods

Patient age, gender, and refractive errors were examined. The deviation angles were measured at near and distance using a prism cover test and were followed by the measurement of the interpupillary distance. The AC/A ratio was calculated using a heterophoria and a gradient method.

Results

The present study consisted of 59 patients, 38 patients with RAET and 21 normal children. The mean ages were 9.6 years in patients with RAET and 9.0 years in the normal children. The refractive errors in spherical equivalent were shown to be 4.6D in the right eye and 4.5D in the left eye in patients with RAET and −0.4D and −0.5D in the normal children. The mean values of the AC/A ratio using a gradient method were 1.8 in patients with RAET and 2.2 in the normal children(p=0.44). According to the heterophoria method, the AC/A ratio was 6.2 in patients with RAET and was 5.4 in the normal children(p=0.04). Conclusions: The AC/A ratio of child patients with RAET was higher than that of normal children when using a heterophoria method. However, there was no difference in the AC/A ratio between the normal children and RAET child patients when using gradient method.

Keywords: Ratio of accommodative-convergence to accommodation, Refractive accommodative esotropia

References

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Table 1.
The gender and number of patients of both groups
Groups Gender Number of patients
RAET* Male 16
  Female 22
Control Male 7
  Female 14
Total   59

* RAET=refractive accommodative esotropia.

Table 2.
The average deviation after correction of refractive error
  RAET* Control
Near +§3.6±3.69△† −‡0.5±4.60△
Far +1.6±2.33△ −0.1±1.61△

* RAET=refractive accommodative esotropia

† △=prism diopters

‡ -=exodeviation

§ +=esodeviation.

Table 3.
The average ratio of accommodative-convergence to accommodation of both groups
  RAET* Control P value
Heterophoria method 6.21±1.31 5.4±1.31 0.04
Gradient method 1.80±1.34 2.2±1.10 0.44

* RAET=refractive accommodative esotropia.

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