Revised Criteria Lead To More Accurate Screen For ROP In Premature Infants

A multicenter group of 41 hospitals led by researchers at Children’s Hospital of Philadelphia has confirmed that an improved method for predicting retinopathy of prematurity (ROP) was able to reduce the number of babies having invasive diagnostic examinations by nearly a third, while raising disease detection up to 100%. If implemented, this screening approach could considerably reduce both unnecessary healthcare costs and physically stressful retinal examinations for premature infants.

The new method described by the study team adds slow weight gain to the existing criteria for ROP screening. Slow growth is a sign of low growth hormones that are involved in the development of ROP. Because nurses routinely measure weight gain in infants, these simple measurements are readily available. The findings of the large, prospective study were published in JAMA Ophthalmology.

ROP is a disorder of the blood vessels of the retina that affects premature babies born with immature retinas. In general, the more premature the baby and the lower the birth weight, the greater the risk for developing ROP. Since the disease has no external signs or symptoms when it first develops, it can only be properly detected through an eye exam. Cases of ROP range in severity, with corrective laser surgery treatment or intraocular injection sometimes required for severe cases to prevent progression and blindness.

Each year in the United States, approximately 70000 infants meet the existing screening criteria and receive examinations for ROP. The current criteria have relatively low specificity for predicting which infants are at risk for severe ROP, with just 5% to 10% of infants screened requiring treatment, and only about half developing ROP. Additionally, while sensitivity for predicting severe ROP is very high under these criteria, it is not 100% with current methods. Therefore, there are opportunities to improve the screening accuracy in multiple ways.

“We developed a new set of criteria that appeared to more accurately predict ROP, but before they could be used in clinical practice, we had to test them thoroughly to ensure that all high-risk infants are examined,” says Gil Binenbaum, MD, MSCE, an attending surgeon in the Division of Ophthalmology and the Richard Shafritz Endowed Chair of Ophthalmology Research at CHOP, chair of the Postnatal Growth and ROP (G-ROP) Study Group that performed the research, and the first author of the study.

In a previous study, Binenbaum and his colleagues developed the new criteria using a hybrid modeling approach that combined birth weight and gestational age criteria, weight gain comparisons to expected growth from infants without ROP, and user-friendly screening criteria. Last year, the study team published the results of a large retrospective study of 7483 babies that they used to develop what they called the “G-ROP criteria.” They found that these criteria were more sensitive than currently used criteria and would greatly reduce the number of infants requiring examinations.

In this latest study, the G-ROP criteria were tested prospectively among 3 981 premature infants at risk of developing ROP across 41 hospitals in the United States and Canada. The researchers found that the G-ROP criteria correctly predicted 219 of 219 cases of type 1 ROP, which requires treatment, while reducing the number of infants undergoing examinations by 36%. When the cohorts from the 2 studies were combined, the G-ROP criteria correctly predicted 677 of 677 type 1 cases, while reducing the number of infants receiving examinations by 33% among the 11464 babies.

“This study successfully validated the accuracy of the G-ROP screening criteria, which now can be used clinically to reduce the number of infants receiving eye examinations for ROP,” Binenbaum says. “Based upon these new findings and the findings of our previous study, we recommend that these criteria are incorporated into national ROP screening guidelines.”

Reference

Binenbaum G, et al. Validation of the postnatal growth and retinopathy of prematurity screening criteria. Published online ahead of print November 14, 2019. JAMA Ophthalmol.