Agreement between grating acuity at age 1 year and snellen acuity at age 5% yiears in the preterm child

Purpose. To examine the relation between grating acuity at age 1 yr and Snellen acuity at 5V4 yrs in preterm children with birth weights <1251 g. Methods Subjects were participants in the multicenter study of cryotherapy for retinopathy of prematurity who had visual acuity measured at age 1 yr with Teller acuity cards and at age 5Yx yrs with the ETDRS chart. Data are presented for 523 eyes that were sighted and 93 eyes that were blind at 1 yr. 63 eyes that developed pathology between 1 and 5% years were excluded. Grating acuity was categorized as favorable if acuity was in the normal range (>1.6 cpd) or <1 octave below normal (>0.8 cpd). Snellen acuity was categorized as favorabl 3 if acuity was in the normal (20/40 or better) or below normal (worse than 20/40 to better than 20/200) range. Results Of eyes that were sighted at 1 yr, 99.2% had grating acuity at 1 yr and Snellen acuity at 5H yrs that were in the same category (favorable/unfavorable). All eyes that were blind at 1 yr had acuity in the unfavorable category at 5Vi yrs. Among eyes with normal or below normal acuity at 1 yr, 86.6% had Snellen acuity at 5y> yrs in the same category (normal/below normal). Correlation analysis indicated a limited ability to make quantitative predictions of Snellen acuity at 5Vs yr from grating acuity at 1 yr. Conclusions. Grating acuity at ace 1 yr allows categorical, but not highly quantitative, prediction of Snellen acuity at 5V4 yrs in preterm children.