What is Retinopathy of Prematurity?

When a child is born prematurely, the child is at risk for several conditions related to the lack of development of the body in the womb. Among those conditions is retinopathy of prematurity.

What Constitutes a Premature Birth?

A full-term birth is considered to be at forty weeks but any birth after week thirty-nine is typically included in the full term grouping as opposed to premature.

Any child born before thirty-nine weeks of gestation is at a risk of developing retinopathy of prematurity, however, if the child also has a low birth weight or requires extended supplemental oxygen is considered high risk.

How does Retinopathy of Prematurity Occur?

Retinopathy of prematurity is a condition that affects the blood vessels in the back of the eye, the retina.

In retinopathy of prematurity, these blood vessels do not fully form before the birth and as a result some portion of the retina will not have blood supply or oxygen.

Since the blood vessels develop late in gestation, it is common for a premature child to have some portion of the retinal vasculature not developed.

The blood vessels develop from the center of the optic nerve outwards to the periphery of the retina.

As the blood vessels develop from the center outward, there is a variety of stages and zones of retinopathy of prematurity.

What are the Stages of Retinopathy of Prematurity?

There are five stages of retinopathy of prematurity, each given a number from one to five.

Stage 1 of retinopathy of prematurity occurs when a pigment demarcation line is present to separate the vascularized retina from the avascular retina.

This stage is a very mild presentation and can be monitored for any changes.

Stage 2 of retinopathy of prematurity occurs when the line of separation is raised or becomes a ridge.

Just like with stage 1 of retinopathy of prematurity, this stage can be monitored for changes.

Stage 3 of retinopathy of prematurity occurs when there is proliferation or growth of new vessels into the avascular zone.

This stage may also have hemorrhages or other visible changes to the retina and may require treatment as opposed to being monitored only.

Stage 4 of retinopathy of prematurity occurs when there is a partial retinal detachment located at the base of the separation between the vascular and avascular regions.

This stage will always require a treatment to attempt to preserve the remaining attached retina.

Stage 5 of retinopathy of prematurity occurs when there is total retinal detachment located between the regions of vascular and avascular retina.

What are the Zones of Retinopathy of Prematurity?

There are three zones in retinopathy of prematurity. These zones indicate how far into the periphery the blood vessels have developed.

Zone 1 is the most central, zone 2 more peripheral, and zone 3 is the furthest developed into the periphery.

How is Retinopathy of Prematurity Treated?

The biggest concern with retinopathy of prematurity is a tractional retinal detachment.

A retinal detachment can occur in retinopathy of prematurity and separate the retina from the underlying structures.

A retinal detachment can be prevented with laser treatments in stage 3 of retinopathy of prematurity.

If the retinal detachment is already occurring, there are laser and surgical treatment options available to reattach the retina.

When to Have a Child Screened for Retinopathy of Prematurity

Today, almost all newborns are screened for retinopathy of prematurity in the hospital days or weeks after birth.

If your child was born premature, the child should be evaluated regularly to ensure that there is no progression or other developments.