Amblyopia after unilateral infantile cataract extraction after six weeks of age.

Purpose: To determine interocular grating acuity difference in children treated for unilateral infantile cataract.

Methods: A group of 27 children previously treated for unilateral infantile cataract, had their monocular visual acuity measured by sweep visual evoked potentials. Interocular grating acuity difference was calculated as the absolute subtraction of monocular acuity scores. Lens status, opacity severity and eye alignment were considered for analysis.

Results: Mean interocular grating acuity difference obtained from unilateral cataract patients was 0.58 +/- 0.20 logMAR. This result was significantly larger than 0.10 logMAR used as normative data. Children with severe opacities had a more pronounced amblyopia than the moderate ones. No significant correlation between amblyopia and strabismus or aphakia was found.

Conclusions: Interocular acuity difference in this group of unilateral congenital cataract was more pronounced than previous reports, mainly because of delay in diagnosis, surgery and optical correction.