In premature babies the blood supply of peripheral retina is not fully developed. This avascular retina stimulates growth of abnormal new blood vessels, which cause shrinkage of the retina and can ultimately lead to retinal detachment, and permanent blindness. This abnormal vascularisation and its sequelae is called Retinopathy of Prematurity (ROP).
All babies with a birth weight of less than 1700 gms, those born at less than 35 weeks of pregnancy, or any pre-term baby who has had problems like infection, breathing trouble etc should undergo ROP screening. The initial retinal examination should be done within one month of birth, followed by weekly or fortnightly checkup depending on the retinal status. The retina is checked with the help of Indirect Ophthalmoscopy.
ROP needs to be treated as soon as it reaches a critical stage called Threshold ROP. The simple treatment is with laser or cryotherapy (freezing) helps in preventing sight threatening complication in most of these children. Untreated ROP may lead to marked visual loss. All premature babies need regular eye examination till they start going to school, for delayed complications like myopia.