J Korean Ophthalmol Soc.  2010 Jul;51(7):988-991. 10.3341/jkos.2010.51.7.988.

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

• Lee DC
• Park JH
• Lee YC
• Lee SY

• KMID: 2213779
• DOI: http://doi.org/10.3341/jkos.2010.51.7.988

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.

Keyword

Ratio of accommodative-convergence to accommodation; Refractive accommodative esotropia

MeSH Terms

Child
Esotropia
Eye
Humans
Refractive Errors

Reference

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