Assessing visual function in children younger than 1 1/2 years with normal and subnormal vision: evaluation of methods.

ABSTRACT

PURPOSE: Methods for detecting subnormal vision early in life are needed to adequately diagnose the condition and begin treatment and rehabilitation. METHODS: Forty-six children ages 1 month to 1 1/2 years with either assumed normal vision, visual impairment due to eye disease, or strabismus were examined with the following tests Stycar rolling balls; preferential looking (Teller acuity cards); and the ability to detect raisins, puffed rice, and sugar strands on two different backgrounds, one white and one black. RESULTS: Children with visual impairment and strabismus often showed normal values for their age, and children with assumed normal vision sometimes had values below those established for normal development of vision with the Stycar rolling balls and the Teller acuity cards. CONCLUSIONS: It is not possible to use these tests to reliably differentiate among normal vision, visual impairment, or strabismus in children younger than 1 1/2. Not until recognition acuity, symbols, or letters can be tested can reliable results be obtained. However, the tests are useful to estimate the general visual function of children in this age group.