About Retinopathy of Prematurity
Retinopathy of prematurity (ROP) is a disease of the eyes that occurs only in premature infants. A premature child is born before 37 weeks of gestation. ROP, however, is most common in preterm babies born between 24 and 31 weeks.
During pregnancy, the blood vessels in the retina grow very slowly and are only fully developed around the date of the expected delivery (i.e. “full term”). The retina is the layer that lines the inside of the eye like wallpaper and can receive light signals. If a child is born preterm, the blood vessels in the retina are not fully developed. Areas of the retina without blood vessels produce a growth factor (VEGF) that stimulates blood vessels to grow into these areas. This may lead to full coverage of the retina with normal blood vessels not causing any problems. However, when too much VEGF is produced, the blood vessels can grow uncontrolled and partially out of the retina into the vitreous (the viscous substance between the retina and the front of the eye). When this happens, the retina can detach from the underlying tissue, which can ultimately lead to permanent vision loss and even blindness. The aim of the Ophthalmologist screening for ROP is to detect such developments and intervene before this happens.
The two major risk factors for developing ROP are low birth weight and very preterm birth. Especially babies born before 31 weeks and with a birth weight of less than 1500g are at a higher risk for ROP. But even in this group of extremely small babies not all develop a form of ROP that requires treatment. In order to identify each baby that needs treatment, screening for ROP is very important. When a stage of ROP that needs treatment is seen during the screening process, then treatment often needs to take place within a few days, sometimes even on the next day.
Regular screening for ROP is extremely important!
Until a few years ago almost all babies who developed a stage of ROP that required treatment were treated with laser coagulation. Retinal tissue treated with laser can no longer produce the growth factor VEGF that stimulates the blood vessels to grow misdirected into the vitreous and retinal detachment can in most cases be prevented. Laser therapy is a useful and validated treatment option with good long-term data. A newer treatment option is offered by agents (called VEGF inhibitors) that are injected into the vitreous. The injected molecules bind and inactivate VEGF. The bound growth factor can then no longer stimulate the blood vessels to grow misdirected into the vitreous and retinal detachment can in most cases be prevented.
With these two treatment options (laser or injection), the vast majority of stages of ROP can be treated. Only very advanced (and rare) stages need to be treated by surgery. Both laser and injection have their specific advantages and disadvantages, which your treating Neonatologists and Ophthalmologists will take into account and discuss with you in order to find the best treatment for your child.