Congenital and traumatic cataract. The effect on ocular axial length.

Elongation of the eye is one of the drawbacks of implanting intraocular lenses in children. To evaluate possible effects of cataract and aphakia on eye elongation, we measured the axial length in children with unilateral aphakia (15 children with congenital cataract and 27 with traumatic cataract) and in children with bilateral congenital cataract (operated on in 14 cases and not operated on in eight cases). In all cases of unilateral aphakia, the aphakic eye was consistently longer than the normal fellow eye. Excessive eye elongation was related to corresponding reduction in visual acuity. The presumed rate of elongation was quantitatively expressed using the time elapsed since surgery and the age of the child. In bilateral congenital cataract, the axial length measured in aphakic eyes that were operated on was similar to that in eyes that were not operated on. We suggest that unilateral cataract or aphakia is associated with excessive eye elongation of affected eyes. Eye elongation seems to be related to amblyopia and poor vision rather than to aphakia.