What is retinopathy of prematurity?
Retinopathy of prematurity (ROP) is a potentially blinding eye disorder that primarily affects premature infants that are born before 30-35 weeks of gestation, and most of whom also have low – very low birth weight. A full-term pregnancy has a gestation of 38–42 weeks. The smaller a baby is at birth, the more likely that baby is to develop ROP. This disorder—which usually develops in both eyes—is one of the most common causes of visual loss in childhood and can lead to lifelong vision impairment and blindness.
Frequently Asked Questions about Retinopathy of Prematurity
How many infants have retinopathy of prematurity?
Today, with advances in neonatal care, smaller and more premature infants are being saved. These infants are at a much higher risk for ROP. Not all babies who are premature develop ROP. The disease improves and leaves no permanent damage in milder cases of ROP. About 90 percent of all infants with ROP are in the milder category and may not need treatment. However, infants with more severe disease can develop impaired vision or even blindness. have Most babies who develop ROP have stages I or II. However, in a small number of babies, ROP worsens, sometimes very rapidly. Untreated ROP threatens to destroy vision. Hence all premature babies need to be examined by a retinal surgeon as soon as they are stable for examination.
Can ROP cause other complications?
Yes. Infants with ROP are at higher risk for developing certain eye problems later in life, such as retinal detachment, myopia (near sightedness), strabismus (crossed eyes), amblyopia (lazy eye), and glaucoma. In many cases, these eye problems can be treated or controlled.
Causes and Risk Factors
What causes ROP?
ROP occurs when abnormal blood vessels grow and spread throughout the retina, the tissue that lines the back of the eye. These abnormal blood vessels are fragile and can leak, scarring the retina and pulling it out of position. This causes a retinal detachment. Retinal detachment is the main cause of visual impairment and blindness in ROP.
Several complex factors may be responsible for the development of ROP. The eye starts to develop at about 16 weeks of pregnancy, when the blood vessels of the retina begin to form at the optic nerve in the back of the eye. The blood vessels grow gradually toward the edges of the developing retina, supplying oxygen and nutrients. During the last 12 weeks of a pregnancy, the eye develops rapidly. When a baby is born full-term, the retinal blood vessel growth is mostly complete (The retina usually finishes growing a few weeks to a month after birth). But if a baby is born prematurely, before these blood vessels have reached the edges of the retina, normal vessel growth may stop. The edges of the retina at the periphery may not get enough oxygen and nutrients.
Scientists believe that the periphery of the retina then sends out signals to other areas of the retina for nourishment. As a result, new abnormal vessels begin to grow. These new blood vessels are fragile and weak and can bleed, leading to retinal scarring. When these scars shrink, they pull on the retina, causing it to detach from the back of the eye.
Are there other risk factors for ROP?
In addition to birth weight and how early a baby is born, other factors contributing to the risk of ROP include anemia, blood transfusions, infections, respiratory distress, breathing difficulties, and the overall health of the newborn child.
How is ROP treated?
The most effective proven treatments for ROP are laser therapy and intravitreal injection of anti-VEGF agents.
Laser therapy “burns away” the periphery of the retina, which has no normal blood vessels. Laser treatment destroys the peripheral areas of the retina, slowing or reversing the abnormal growth of blood vessels. Unfortunately, the treatment also destroys some side vision. This is done to save the most important part of our sight the sharp, central vision we need for “straight ahead” activities such as reading, sewing, and driving.
Intravitreal injection of anti VEGF agents are comparatively newer modality of treatment which is reserved for “plus disease” or more severely affected retina (in which the blood vessel growth is very minimal).
More severe stages of ROP do require surgery.
In any case, a newborn born prematurely needs regular screening visits by a VitreoRetinal specialist to determine if he/she is suffering from ROP and/or whether he/she requires treatment for the same.
