Treatment of retinopathy of prematurity (ROP) outside International Classification of ROP (ICROP) guidelines

Aim To evaluate the incidence and clinical indications for which eyes were treated for retinopathy of prematurity (ROP) outside the guidelines set by International Classification of ROP (ICROP). Methods Medical records of the patients treated at a single tertiary care ophthalmology hospital for ROP from January 2016 to December 2019 were retrospectively analysed to evaluate the indications for which they were treated. Results Out of 241 eyes, 33 eyes (13.7%) were treated outside the guidelines. The reasons for the treatment outside the guidelines were structural changes ( n = 24, 72.7%), persistent stage 3 ROP that did not show any sign of regression for 6 weeks ( n = 7, 21.2%) and active ROP with fellow eye being treated ( n = 2, 6.1%). The recorded specific structural changes were tangential traction with temporal vessel straightening concerning for macular distortion and ectopia ( n = 5, 15.2%), and stage 3 neovascularisation or ridge with anteroposterior traction with risk of progression to stage 4 disease ( n = 19, 57.6%). Pre-plus disease was present in 11 eyes (33.3%).After the treatment, ROP stages regressed and retinal vessels grew either until the ora or at least into zone III in all the treated eyes. None of the eyes showed worsening of structural changes after treatment. The mean follow-up of the patients was 12.4 ± 11.7 months. Conclusion Experts occasionally recommend treatment in eyes with disease milder than type 1 ROP. This study may help paediatric retinal practitioners in decision-making in borderline cases.