Eye patching and visual evoked potential acuity in children four months to eight years old.

The monocular visual acuities of six children aged 4 months to 8 years were measured using visual evoked potentials (VEP's) before and during patching therapy. A seventh child had both Snellen and VEP monocular acuities determined before patching. In a cooperative child, it was estimated that VEP acuity was within 0.25 octaves (one line on an eye chart) of Snellen acuity. In the four children less than 3 years of age, patching resulted in a 1.8-octave decrease in acuity of the patched eye and a 2.0-octave improvement in the unpatched eye. After cessation of patching therapy, acuity of the previously patched eye improved 2.0 octaves and that of the abnormal eye declined 1.75 octaves. In the two children older than 4 years, patching resulted in 1.25-octave acuity decrease in the patched eye. Cessation of patching resulted in a 1.25-octave improvement in acuity of the patched eye. No permanent deleterious effects of patching on acuity were observed.