Validation of the 'TWO-ROP' algorithm in a tertiary Care Centre in Greece

The TWO-ROP algorithm is a modified screening protocol based on US data for low-risk infants that limits screening to a single outpatient exam at 38 or 40 weeks to reduce the retinopathy of prematurity (ROP) screening burden without compromising safety. The aim of this study was to validate the algorithm on an external data set outside the United States.

This is a retrospective study of premature infants screened for ROP at a tertiary centre in Greece. Infants with higher birth weight (BW) and greater gestational age (GA) were included and stratified into three groups: group 1 (BW < 1500 g, GA ≥ 32 weeks), group 2 (BW ≥ 1500 g, GA < 32 weeks) and group 3 (BW ≥ 1500 g, GA ≥ 32 weeks). The rate of ROP and type 1 ROP were evaluated.

Five hundred and fifty-three of the 1251 infants (44.2%) met the inclusion criteria. Groups 1, 2 and 3 had 139 (25.1%), 283 (51.2%) and 131 (23.7%) patients. Fourteen patients (2.5%) had ROP, including 7 in group 1, 7in group 2 and 0 in group 3 (p < 0.001). No patient met the criteria for type 1 ROP. No cases of treatment warranted ROP (TW-ROP) were observed in the cohort, indicating no missed cases under the TWO-ROP algorithm. When applying the algorithm, 14.3%-14.9% (mean 14.6%) of ROP examinations were saved.

The TWO-ROP algorithm can reduce examinations while ensuring safety in Greece when using the local screening guidelines. This is the first ex-US validation and supports the potential for risk-stratified screening globally to optimize resources while maintaining safety.