Evaluation of aggressive posterior retinopathy of prematurity (AP-ROP) in the German Retina.net ROP registry

Purpose Aggressive (posterior) retinopathy of prematurity (A-ROP/AP-ROP) may progress rapidly into tractional retinal detachment if not treated timely. Fortunately, this type of treatment-warranted ROP is rare in developed countries. As a consequence, data on risk factors for development of this aggressive form of ROP is sparse. In this study, we aim to analyse the risk factors for the development of AP-ROP using data from the German Retina.net ROP registry and report functional outcomes of patients treated for AP-ROP. Methods We assessed the observational German Retina.net ROP registry for infants born between 2011 and 2020 and treated for unilateral or bilateral aggressive posterior ROP (AP-ROP) ( N = 21). These infants were compared to infants treated for ROP without AP-ROP (control group; N = 329) regarding demographics, neonatal parameters, ROP management and functional outcomes. Results Of 350 infants treated for any ROP, 21 (6%) were diagnosed with unilateral or bilateral AP-ROP [38 of 686 eyes (5.5%)], predominantly in zone I (77%). Infants with AP-ROP were born at a significantly younger gestational age (24.3 vs. 25.4 weeks; p = 0.0001) and with a lower birth weight (595 vs. 697 g; p = 0.0262). Treatment occurred at a significantly lower postmenstrual age (PMA) and postnatal age (PNA). Treatment consisted mainly of intravitreal anti-VEGF therapy (79% of eyes) [compared to laser photocoagulation for controls (60%)]. Eyes with AP-ROP required more retreatments (39% vs. 15%; p = 0.0002). At follow-up of approximately 12 months PNA, 12/15 eyes with AP-ROP had central fixation and 6/15 eyes exhibited strabismus. Median spherical equivalent of eyes with AP-ROP ( N = 16) was 0.0 dpt (interquartile range: −2.6 to 1.0 dpt). One child developed complete retinal detachment in 1 eye and 1 child partial retinal detachment in 1 eye. Conclusion Our study confirmed known risk factors for the development of AP-ROP such as low GA and low birth weight, whereas other previously reported risk factors such as male sex and certain comorbidities were not observed in our cohort. Our data provide additional insight into AP-ROP treatment patterns including earlier time of treatment, higher risk for retreatment, and therapy preference for intravitreal anti-VEGF therapy.