The analysis of AC/A ratio in nonrefractive accommodative esotropia treated with bifocal glasses.
OBJECTIVE
To report the long term results of bifocal treatment in nonrefractive accommodative esotropia and to analyze the changes of accommodative convergence to accommodation (AC/A) ratio.


METHODS
Sixteen patients treated with bifocal glasses for at least 5 years were evaluated retrospectively. Angle of deviation at near and distance, refractive error, and AC/A ratio by the lens gradient method were analyzed. The changes of AC/A ratios were also compared after dividing the patients according to continuation or cessation of bifocal therapy.


RESULTS
Six patients (38%; bifocal stop group, BSG) were able to stop using bifocal glasses at an average age of 10.8 years (range, 6.5 to 15.4 years) during their follow-up. However, the other ten patients (62%; bifocal continue group, BCG) had to continue using bifocal glasses until the final visit, which was 13.8 years on average (range, 11.3 to 18.5 years). The AC/A ratio decreased from time of bifocal prescription to the last visit in both groups, from 4.4 to 2.7 in the BSG and from 5.9 to 4.5 in the BCG. AC/A ratios were significantly higher (p = 0.03) in the BCG than that of the BSG from the beginning of bifocal treatment and this difference was persistent until the final visit (p = 0.03).


CONCLUSIONS
The AC/A ratio decreased with age in both groups but was significantly higher throughout the entire follow-up period in the BCG. AC/A ratio at bifocal prescription could be an important factor in predicting response to bifocal treatment.
B&VIIT Eye Center, Seoul, Korea.
Wook Kyum
WK
Kim
Sung Yong
SY
Kang
Soolienah
S
Rhiu
Seung Ah
SA
Chung
Jong Bok
JB
Lee
D000065:Accommodation, Ocular / Q000502:physiology*; D000293:Adolescent; D002648:Child; D003519:Cyclopentolate / Q000008:administration & dosage; D004948:Esotropia / Q000503:physiopathology* / Q000628:therapy*; D005139:Eyeglasses; D005260:Female; D006801:Humans; D008297:Male; D010656:Phenylephrine / Q000008:administration & dosage; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D014331:Tropicamide / Q000008:administration & dosage
D010656:Phenylephrine; D003519:Cyclopentolate; D014331:Tropicamide