Retinopathy of Prematurity

Definition | Symptoms |  Treatment |  Clinic Information

Definition
Retinopathy of prematurity (ROP) occurs in premature babies when abnormal blood vessels and scar tissue grow over the retina. The retina is the light detecting layer of cells at the back of the eye that allows us to see. Abnormal blood vessels and scar tissue can grow over the retina in premature babies with ROP. An ophthalmologist can detect ROP during an examination of your baby's dilated eyes in the neonatal intensive care unit (NICU) or nursery.

The causes of ROP are not completely understood. The retinal blood vessels in some very small, premature babies seem to develop abnormally during the therapy necessary for the infant's survival. It was once thought that oxygen, given to almost all premature babies, was entirely responsible for all cases of ROP, but newer evidence indicates this is not true. How premature your baby is and their birthweight are factors which appear to influence ROP. For example, a baby who weighs 3 pounds at birth has about a 5% chance of developing ROP; an infant weighing less than 2 pounds has a 40% chance of developing ROP.

Will ROP Affect Vision?
It is difficult to predict whether vision will be affected. In many infants, the abnormal blood vessels shrink or go away without affecting vision. In other infants with more extensive disease, bleeding and scar tissue may lead to distortion or detachment of the retina. This may result in moderate to severe loss of vision. Only a very small percentage of babies become blind. Nearsightedness (myopia) is common in children with ROP. Glasses may improve the vision of these children, unless the eye is badly damaged.

Can ROP be Prevented?
Unfortunately, clinical research has not yet found a way to prevent ROP in all babies. The sophisticated medical care provided in modern neonatal intensive care units has improved the survival chances of very small babies. Because more premature infants survive, ROP has become more common.

Symptoms
Premature infants do not have symptoms. External signs develop only after disease has become severe or progressed to retianl detachmetns. Timely detection of ROP depends upon examination by an ophthalmologist experienced in the examination of premature infants.

Treatment
Most babies' eyes with ROP do well without any treatment. In more severe cases, cryotherapy (freezing) and/or laser surgery may be used. The pen-like tip of the cryotherapy instrument, a cryoprobe, can briefly freeze side areas of the retina through the outer wall of the eye. Laser photocoagulation surgery may also be used to treat the side areas of the retina. These treatments can slow down or reverse the abnormal growth of blood vessels and scar tissue in more severe ROP. It may be necessary for your ophthalmologist to examine a baby frequently while the infant is in the NICU or nursery before a treatment can be recommended. Important factors in the decision include where ROP is located in the eye, how severe it is, and how it is progressing.

Even with treatment, there is still a definite risk of serious vision loss. The long-term effects of cryotherapy and laser surgery for ROP are not known. If severe ROP disease pulls the retina out of place, more complex surgical procedures can sometimes restore limited vision. Other ROP complications such as glaucoma and misaligned eyes may also require surgery later in life. Periodic eye examinations will be necessary as your baby grows, to ensure that the child's vision is developing as normally as possible.

Clinic Information
For more information, see the Retina, Uveitis & Ocular Oncology Clinic at the U-M Kellogg Eye Center.