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Retinopathy of prematurity in extremely premature infants
Ronald G W Teed1, Richard A Saunders
1Storm Eye Institute, Medical University of South Carolina, Department of Ophthalmology, Charleston, South Carolina 29425-6760, USA. teed@musc.edu
Insights
Extremely premature infants (<25 weeks estimated gestational age) show higher rates of retinopathy of prematurity (ROP), including severe Type 1 ROP. However, the overall incidence may be lower than previously thought, with birth weight not significantly impacting Type 1 ROP risk in this group.
Area of Science:
- Ophthalmology
- Neonatology
- Perinatal Medicine
Background:
- Retinopathy of prematurity (ROP) remains a significant concern in extremely premature infants.
- Increasing survival rates of infants born before 27 weeks estimated gestational age (EGA) necessitate updated ROP incidence and severity data.
- Previous ROP studies may not reflect current outcomes in the most vulnerable premature populations.
Purpose of the Study:
- To compare the incidence and characteristics of ROP in infants born <25 weeks EGA versus those born 25 to 27 weeks EGA.
- To evaluate the development of Type 1 ROP in these distinct extremely premature infant groups.
- To assess the influence of birth weight and postmenstrual age on ROP development.
Main Methods:
- Retrospective chart review of 231 infants born before 27 weeks EGA.
- Infants categorized into two groups: <25 weeks EGA and 25 to 27 weeks EGA.
- Analysis of ROP incidence, Type 1 ROP development, and associated factors like birth weight and postmenstrual age.
Main Results:
- ROP developed in 87% of infants <25 weeks EGA compared to 62% in the 25 to 27 weeks EGA group.
- Type 1 ROP occurred in 23% of infants <25 weeks EGA versus 9% in the 25 to 27 weeks EGA group.
- Lower birth weight predicted Type 1 ROP risk in the 25-27 weeks EGA group, but not in the <25 weeks EGA group; no difference in diagnosis age.
Conclusions:
- Extremely premature infants (<25 weeks EGA) have a higher likelihood of developing ROP and severe Type 1 ROP.
- The incidence of ROP in this cohort may be lower than previously reported.
- Birth weight and postmenstrual age do not appear to be significant predictors for Type 1 ROP in the <25 weeks EGA group.
Introduction:
The incidence and severity of retinopathy of prematurity (ROP) in extremely premature infants have not been reported since publication of the Early Treatment of ROP study results. The survival rate of these infants continues to increase. We sought to determine the characteristics of ROP in a group of surviving infants <25 weeks estimated gestational age (EGA) at birth compared to a group 25 to 27 weeks EGA at birth.
Methods:
Retrospective review of infants born prior to 27 weeks EGA between January 2003 and July 2007 at a level-3 nursery at a regional academic medical center.
Results:
A total of 231 medical records were reviewed and found to have analyzable data. Of 79 infants <25 weeks EGA, 69 (87%) developed ROP, compared to 95 of 152 (62%) infants 25 to 27 weeks EGA. Type 1 ROP developed in 23% of infants in the <25 weeks EGA group, compared to 9% of infants in the 25 to 27 weeks EGA group. There was no difference in mean postmenstrual age when type 1 ROP was diagnosed. Lower birth weight predicted increased risk of type 1 ROP in the 25 to 27 weeks EGA group, but not in the <25 weeks EGA group.
Conclusions:
Extremely premature infants are more likely to develop ROP and type 1 ROP, but the incidence may be lower than previously reported. Birth weight may not influence the incidence of type 1 ROP in this group of infants. Type 1 ROP does not develop at an earlier postmenstrual age in the extremely premature infant.
