[Delayed development of binocular function in the long postoperative period of infantile esotropia]

Long-term observation of binocular function was carried out in 30 postoperative cases of infantile esotropia. The period of observation was 5 to 12 years and the targets used for evaluation were deviating angle and stereo acuity. In the successful group, 20 cases out of 30 (67%) achieved a stereo acuity of 60 seconds or better. Among the remainder, partial improvement was seen in 20% and no improvement in 13%. Preexisting amblyopia and ARC improved in the successful group, and the final deviating angle was a mean of 2.3 prism diopter. There were 2 types of cure processes in the successful group. The first group achieved a good binocular function in a relatively early postoperative stage (7 cases), while the second group had delayed development of binocular function over a period of several years (13 cases). The former cases had sufficient orthoptic treatment during admission and the latter showed a gradual improvement of stereo acuity accompanied by good eye position. It has been generally accepted that the rate of binocular function recovery is very poor among cases of infantile esotropia, but our study revealed that skillful orthoptics administered by a selected member of our team over an extended period enabled the achievement of good binocular function in infantile esotropia.