Comparative study of visual functions in premature pre-school children with and without retinopathy of prematurity

Purpose: Observe whether there are differences in visual functions among pre-mature infants with treated retinopathy of prematurity (ROP) in relation to preterm infants with ROP and spontaneous regression; and among these two groups with ROP and the control group without ROP. Methods: Cross-sectional observational no blind study. Premature infants were born between 06/1992-06/2006 and were exam between 06/2009-12/2010; registered in data of Hospital de Olhos Sandalla Amin Ghanem; with gestational age less than or equal to 32 weeks and 1,599 g born weigh; without ROP and ROP stages II or III, in one of the eyes, with spontaneous regression or with treatment; at least three visits during the selection period at maximum 6 months in the first exam and minimum 4 years of age in reassessment (chronological age) were include. Premature that did not respond or were not located for reassessment and those that did not have conditions to do the exams were exclude. Study's groups: G1-ROP post-treatment; G2-ROP post-spontaneous regression; G3-without ROP (control). Visual function evaluated with visual acuity (VA), contrast sensitivity test (CST), color test (CT), eye movement, stereopsis. Results: Overall, there were 24 premature infants and 48 eyes. Normal VA: 64.28% (G1), 87.5% (G2) and 100% (G3); Normal CST: 66.67% (G1), 100% (G2) and 55.56% (G3); Normal Ishihara CT: 100% (G1 and G2) and 86% (G3); Normal Farnsworth CT: 20% (G1), 75% (G2) and 50% (G3). Normal stereoacuity: 0.00% (G1); 25% (G2) and 3.5% (G3). Strabismus: 37% (G2), 0.00% (G1 and G3). The prevalent tendency for lower response in CST and CT between the premature children in group G3 and Farnsworth color test in G1 is a curious result of this work and more study is necessary about these visual functions in older premature children. Conclusion: The visual functions showed no statistically significant difference among the groups studied.