Early visual acuity measurements appear a misleading predictor of long-term acuity in extremely low birth weight infants

Reinforcing the need for continued long-term follow-up in extremely low birth weight infants, researchers have shown in a prospective, longitudinal study of 139 babies weighing less than 1001 g that early measurements of visual acuity, especially a result within the normal tolerance limits, may be misleading as a predictor of long-term visual prognosis. Over a third of the children with normal grating acuity before seven months of age had abnormal long-term recognition acuity.

The most predictive factor of a poor late visual acuity was the rate of development, as calculated by the slope - from two or three Teller acuity measurements during the first 24 months of life - of the early visual acuity measurements.

An abnormal slope of visual acuity maturation during the first two years of life results in a 5.5 times greater chance of abnormal long-term recognition acuity outcome.