ROP screening worthwhile for extremely premature infants

COS 2012, July 4 - Extremely premature infants with gestational age of 25 weeks or under have a greater risk of developing type 1 retinopathy of prematurity (ROP) than those with older gestational age. This is important because type 1 ROP requires treatment.

Using data from the Canadian Neonatal Network, researchers investigated ROP screening data of 207 infants whose gestational age was ≤ 27 weeks and who were admitted to a neonatal intensive care unit (NICU) between July 2006 and July 2010. Type 1 ROP was defined according to criteria from the Early Treatment for Retinopathy of Prematurity Study.

Infants were divided into two groups: one with gestational age ≤ 25 weeks (86 infants) and a second group with infants whose gestational age was 26 or 27 weeks (121 infants). Incidence and severity of ROP were assessed for the total screened population and between groups.

There was an overall incidence of ROP of 64.7%, with 88% incidence in the younger group 1 infants and 48% in group 2. There was an overall incidence of 11.6% of type 1 ROP. However, group 1 infants had a significantly higher rate of type 1 ROP (24.4%) compared with group 2 (2.5%), said Dr. Sourabh Arora, currently at the University of Alberta.

There was no association between postmenstrual age at the time of ROP onset with development of type 1 ROP. Earlier presentation of ROP did not predict progression to type 1 ROP.

None of the infants whose gestational age was > 26 weeks or whose birth weight was > 1,000 g developed type 1 ROP. Limiting screening of infants with lower gestational age might suffice to identify those requiring treatment, but more study is needed to confirm this approach.