Retinopathy of prematurity (ROP), a vasoproliferative disorder of the retina occurring principally in new born preterm infants is a major cause of childhood blindness in the world and is increasing in incidence throughout the world. ROP is closely linked to the degree of prematurity with severe ROP being more common in infants of extremely young gestational ages, and is caused by oxygen-induced damage to the developing retinal vasculature, resulting in hyperoxia-induced vaso-obliteration and subsequent delayed retinal vascularization and hypoxia-induced pathological neovascularization. The pathogenesis of ROP consists of an initial phase of low vascular endothelial growth factor (VEGF) levels and beginning with delayed retinal vascular growth after premature birth, followed by phase II when phase I-induced hypoxia releases VEGF to stimulate new blood vessel growth. The use of supplemental oxygen, oxygen concentration and duration are among the most frequently identified risk factors. Supplemental oxygen should be given in small preterm infants less than 28 weeks to maintain oxygen saturations via pulse oximeter in the range of 90-94% until 36 weeks post-menstrual age. Inadequate nutrition, poor postnatal growth, infections, and red blood cell transfusions are the other important predisposing factors. Although there is strong evidence for a genetic predisposition to ROP, specific genetic variants with strong association with ROP have not been detected. Early detection and timely intervention makes screening an important aspect of ROP. A simple screening test done within a few weeks after birth by an ophthalmologist can avoid this preventable cause of blindness. Although screening guidelines and protocols are strictly followed in the developed nations this is lacking in developing countries, which have the highest number of preterm deliveries in the world. In addition, severe ROP is increasingly seen in more mature infants in low/middle-income countries, especially when compared with their counterparts in developed countries. Therefore, it is recommended that each country develops and employs its own specific criteria appropriate for its local population. Treatment with laser photocoagulation should be implemented as soon as possible, at least within 72 hours of determining the presence of this treatable disease, in order to minimize the risk of retinal detachment. Anti-VEGF treatment may hold great promise in the treatment of selected severe cases, but is associated with the unintended effects on delayed eye growth and retinal vasculature development of preterm infants. The therapeutic potential of stem cells in ROP is evident in animal studies, but not in humans. However, delayed cord clamping after birth, and then breastfeeding are accompanied by an increase supply of valuable stem and progenitor cells which makes them natural stem cell transplants for tiny preterm infants. This review would help the pediatricians to update their current knowledge on ROP.

Anahtar Kelimeler: prematurity, pathogenesis, prevention, screening, therapy