Retinopathy of Prematurity Screening Protocol

According to the ROP screening, preterm infants included in the study (≤ 33 weeks of gestational age, ≤ 1800 g of birth weight or assessed by the neonatologist as at high risk of ROP) [14 (link)] underwent a series of eye fundus examinations with binocular indirect ophthalmoscopy. The examinations started from the 4th week of chronological age and were performed every 7–10 days, depending on retinal vascularization and the presence of fundus lesions. The diagnosis of ROP was made when ROP vascular features were found at the junction of vascularized and avascular retina. In accordance with the International Classification of Retinopathy of Prematurity (ICROP), they were classified as ROP stages, including demarcation line (stage 1), ridge (stage 2), extraretinal neovascular proliferation (stage 3), then partial or total retinal detachment (stage 4 and 5) [15 ], [16 ]. Additionally, other important features were described in ROP cases, including zone and presence of plus disease.
According to the Early Treatment for Retinopathy of Prematurity guidelines, patients diagnosed with ROP were qualified for treatment in the case of any stage of ROP in zone I with plus disease, stage 3 ROP with no plus disease in zone I, or stage 2 or 3 ROP with the plus disease in zone II [17 ]. These patients were treated by laser photocoagulation of the peripheral avascular retina or intravitreal administration of anti-VEGF antibody (ranibizumab), within 72 h after the diagnosis. In one patient (2 eyes), anti-VEGF therapy was used as the second line of treatment after laser photocoagulation.
The screening was finished in patients with retinal vascularization reaching zone III or regression of ROP on at least two examinations.