Effect of bilirubin on visuocortical development in preterm infants.

Objective: To determine if visuocortical development in premature infants with high bilirubin levels is more adversely affected than that in full-term infants.

Study Design: 57 preterm infants were managed using institutional guidelines for hyperbilirubinemia. At 12-months corrected age, Vernier acuity, contrast sensitivity, and grating acuity measured using the sweep visual evoked potential (sVEP) were correlated to total serum/plasma bilirubin (TSB) levels in the first week of life.

Result: As TSB levels increased, Vernier acuity worsened in infants <34 weeks' gestation compared with those >34 to <37 weeks' gestation (p < 0.001). Contrast sensitivity varied as a function of TSB levels (Spearman correlation 0.63, p < 0.001). Grating acuity was unaffected.

Conclusion: Vernier acuity in preterm infants <34 weeks' gestation is more vulnerable to the effects of bilirubin, suggesting that the extrastriate visual cortex is primarily affected by bilirubin. Therefore, guidelines for management of hyperbilirubinemia in preterm infants (<34 weeks' gestation) should be revised.