Astigmatism in visually immature child with strabismus.

Astigmatic refractive errors may develop late in the visual maturity period of strabismic children. Seventeen strabismic children who had surgery and ten strabismic children who did not have surgery are discussed; none had astigmatic error at the initial refraction. Significant astigmatism developed in both groups at age 4 years and two years after the initial refraction. The ophthalmologist should be aware that late-developing astigmatism can cause a recurrence or deterioration of strabismus. The best response is serial refractions and appropriate correction of all strabismus patients during the visual maturity period.