Prevalence of ROP severities in a multinational cohort of infants treated for ROP – data from the European ROP registry (EU-ROP)

Abstract

Purpose : In 2021, the third iteration of the International Classification of Retinopathy Of Prematurity (ICROP3) was published. We investigated the prevalence of ROP severities in the recently established European ROP registry (EU-ROP), which collects real-life data of infants treated for ROP in Europe.

Methods : We analyzed data from the first consecutive 203 infants in the EU-ROP registry. These infants were treated at 30 centers in 8 countries located in geographical Europe. The EU-ROP registry collects data exclusively for infants with ROP requiring treatment; data from infants undergoing ROP screening without treatment is not captured. Descriptive statistics were used to analyze demographic parameters (birthweight, gestational age (GA), gender and plurality), as well as ROP severities (stage of ROP, zone and plus disease) at time of first ROP treatment.

Results : Median birthweight was 727g (range: 250 to 2.470g), median GA was 25.9 weeks (range: 22 to 34 weeks). 47.5% of infants were female and 22% were twins. Of the 203 infants 190 were treated bilaterally (93.6%). In two infants the left and right eye were treated at different time points (23 and 92 days apart). Zone II stage 3 with plus disease was the most prevalent disease severity amongst all eyes treated for ROP (43.2%; N=84 eyes). In this disease category, posterior and anterior zone II was almost equally represented (IIp: 40, IIa: 44). The second most prevalent ROP severity was zone II, stage 3 without plus disease in 12.5% (N=26) eyes, again about equally distributed between posterior and anterior zone II (IIp: 14, IIa: 12). In 22 of these eyes (85%) a pre-plus disease was documented. Aggressive ROP (A-ROP) was documented in 10.7% (N=42) of all eyes. Amongst the A-ROP eyes, 64% (N=27) had zone I disease, of which 7 eyes were zone I secondary to notch and 36% (N=15) A-ROP eyes had posterior zone II disease. All other ROP stages were documented in less than 10% of eyes.

Conclusions : This analysis from the EU-ROP registry gives an overview of ROP characteristics present in a real-world cohort of treatment-requiring ROP in Europe. Additional analyses will follow to investigate treatment approaches, complications and outcomes.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.