Objective: To study the incidence and risk factors predisposing to retinopathy of prematurity (ROP) and to assess the outcome after laser photocoagulation.
Design: Prospective cohort observational study.
Setting: Infants admitted to a neonatal intensive care unit of a referral hospital between 2000-2006 and followed up till the age of 3 years.
Methods: Preterm infants with birthweight<1500 g and gestation<or=32 weeks were screened for ROP at 4 weeks after birth or 31-33 post conceptional age, whichever was later. Infants with birthweight>or=1500 g and gestation>32 weeks were screened only if they had additional risk factors. Those found to have threshold disease ROP had laser photocoagulation. They were recalled at 3 years and had a complete ophthalmic check up.
Results: The incidence of ROP in the 552 infants who were screened was 22.3%. No ROP was found in infants weighing>or=2000 g or with a gestational age more than 36 weeks. Risk factors predisposing to ROP were septicemia (P<0.001), apnea (P=0.0001) and oxygen therapy (P=0.031). Out of the 123 infants who had ROP, 41 (33.6%) needed laser photocoagulation. Twenty two (53.6%) were seen at 3 years of age. Ten children had myopia, 1 had amblyopia and 9 children had completely normal structural and visual outcome. Only two (9%) children were blind due to retinal detachment.
Conclusion: One third of the infants with ROP needed laser photocoagulation, the outcome of which was good. Risk factors predisposing to ROP were septicemia, apnea, oxygen therapy and use of blood products.