Clinical Assessment of Accommodative Esotropia

ABSTRACT

Accommodative esodeviation is the result of either the need to clear the blurred vision caused by hypermetropia or a high accommodative convergence to accommodation(AC/A) ratio. In 1958, Parks showed that there were three origins of accommodative convergence to accommodation(AC/A), and a combination of the two. The authors experienced 71 cases of accommodative esotropia which were treated with hyperopic glasses, executive bifocals, and surgery on nonaccommodative component. Accommodative esotropia was subdivided into 3 types as refractive, nonrefractive and combined type. The refractive type was 59.1%, nonrtfractive type 8.5%, and combined type 32.4%. Among all 71cases, partially accommodative esotropia was 32.4%. The onset was at the age between 2 and 4 years in 50.8%. In most cases the sphero-equivalent of refractive error was +4.00 to less than +6.00 D in the refractive type with a normal AC/A ratio, less than +2.00 D in the nonrefractive type with a high AC/A ratio, and +2.00 to less than +4.00 D in the combined type with a high AC/A ratio. The cases with a normal AC/A ratio showed more hypermetropia. The amount of esodeviation controlled by hyperopic glasses was 24.4 to 25.0 delta at distance; by executive bifocals 26.2 delta in the nonrefractive type and 18.6 delta in the combined type at near. Stereoacuity was tested in 34 cases who understood the test, was better in the refractive type with normal AC/A ratio than in nonrefractive and combined type with a high AC/A ratio, and was absent in 26.4%. In many cases without stereopsis, the interval between onset and institution of therapy was too long and the age at treatment was too old. The longer the eyes are not aligned the greater chance for the development of amblyopia and sensory motor misalignant. Therefore early recognition and early initiation of treatment should be emphasized.