Abstract
Abstract: :
Purpose: To report long term changes in visual acuity and refractive error for strabismic, anisometropic, and isoametropic amblyopes. Methods: Records of patients with strabismic amblyopia (SA), anisometropic amblyopia (AA), and isoametropic amblyopia (IA) treated from 1983-1991 were reviewed. Excluded were patients having ocular or neurological disease, developmental delay, and follow-up less than 4 years after treatment cessation. Data included best corrected visual acuity (VA) and spherical equivalent refractive error (RE) of the amblyopic and non-amblyopic eye at pretreatment, posttreatment, and long term follow-up. Results: Records for 61 patients met the inclusion criteria. For SA (n=22) mean VA in the amblyopic and non-amblyopic eyes improved 0.34 and 0.05 logMAR units after a mean treatment time of 1 year. At long term follow-up(mean=9.3 years following treatment), VA in the amblyopic eye regressed 0.10 and VA in the non-amblyopic eye improved 0.03 logMAR units. For AA (n=27) mean VA in the amblyopic and non-amblyopic eyes improved 0.30 and 0.02 logMAR units after a mean treatment period of 1.1 years. At long term follow-up visit (mean =7 years following treatment), VA in the amblyopic eye regressed 0.09 and VA in the non-amblyopic eye improved 0.04 logMAR units. Repeated measures ANOVA showed no significant effect of type of amblyopia on the VA of the amblyopic eye and a significant effect of visit (F(2,90)=34.457, p=.00000)due to treatment and not regression. The changes in VA in the non-amblyopic eye with visit were significant (F(2,90)=26.488, p=.00000) and interacted with type (F(2,90)=5.6644, p=.00482), the changes being larger in SA. For SA, the mean RE in the amblyopic and non-amblyopic eye changed from +1.73 D and +1.64 D initially to +0.03 D and +0.29 D at the follow-up visit. For AA, the mean RE in the amblyopic and non-amblyopic eye changed from +1.06 D and +0.12 D initially to +0.28 D and -0.92 D at the follow-up visit. The effect of visit on the amblyopic and non-amblyopic RE was significant (F(2,40)=8.1016, p=.00111 and F(2,40) =8.2951, P=.00097, respectively). For IA (n=12), VA in the right and left eye initially was 0.43 and 0.38 logMAR units and improved to 0.14 logMAR units in each eye after a mean follow-up of 8 years. RE in the right and left eye changed from -1.35 D and -1.05 D to -2.77 D and -2.79 D. Conclusion: After treatment and with long term follow-up, VA regresses but not significantly in the amblyopic eye in SA and AA. At the same time, VA in the non-amblyopic eye improves slightly. VA also improves significantly over time in IA. The RE of both amblyopic and non-amblyopic eyes tends to show a myopic shift regardless of the type of amblyopia.
Keywords: amblyopia • visual acuity • refractive error development