About Retinopathy of Prematurity
Retinopathy of prematurity (ROP) is a disease that occurs in premature babies. It causes abnormal blood vessels to grow in the retina, the layer of nerve tissue in the eye that enables us to see. This growth can cause the retina to detach from the back of the eye, leading to blindness.
Some cases of ROP are mild and correct themselves, but others require surgery to prevent vision loss or blindness. Surgery involves using a laser or other means to stop the growth of the abnormal blood vessels, making sure they don't pull on the retina.
Because there are varying degrees of ROP, the surgical approach used can differ for each case. The more you know about retinopathy of prematurity and your baby's surgery, the easier the experience is likely to be for you.
Causes of ROP
Retinopathy of prematurity causes blood vessels to grow abnormally and randomly in the eye. These abnormal vessels tend to leak or bleed, which leads to scarring of the retina. When the scars shrink, they pull on the retina, causing it to detach from the back of the eye.
Since the retina is a vital part of vision, its detachment will cause blindness.
Blood vessels grow from the center of a developing baby's retina 16 weeks into the mother's pregnancy, and then branch outward and reach the edges of the retina 8 months into the pregnancy. In babies born prematurely, normal retinal vessel growth may be disrupted and abnormal vessels can develop, which can cause leaking and bleeding in the eye.
ROP can stop or reverse itself at any point, so it often resolves as the baby grows. Sometimes, though, the disease may progress to cause scarring, which pulls the retina away from the rest of the eye.
ROP has no signs or symptoms. The only way to detect it is through an eye examination by an ophthalmologist.
ROP surgery is used to stop the growth of abnormal blood vessels by focusing treatment on the peripheral retina (the sides of the retina) to preserve the central retina (the most important part of the retina). ROP surgery involves scarring areas on the peripheral retina to stop the abnormal growth and eliminate pulling on the retina.
Since surgery focuses treatment on the peripheral retina, these areas will be scarred and some amount of peripheral vision may be lost. However, by preserving the central retina, the eye will still be able to perform vital functions like seeing straight ahead, distinguishing colors, reading, etc.
The most frequently used methods of ROP surgery are:
- laser surgery, the most common type of ROP surgery, in which small laser beams are used to scar the peripheral retina (also called laser therapy or photocoagulation). This procedure lasts about 30-45 minutes for each eye.
- cryotherapy, where freezing temperatures are used to scar the peripheral retina to stop abnormal blood vessel growth. For many years, cryotherapy (also called cryosurgery) was the accepted method of ROP surgery, but it has been all but replaced by laser therapy.
For more-advanced cases of ROP where retinal detachment has occurred, these methods are used:
- scleral buckling, which involves placing a flexible band, usually made of silicone, around the circumference of the eye. The band is placed around the sclera, or the white of the eye, causing it to push in, or "buckle." This, in turn, causes the torn retina to push closer to and remain against the outer wall of the eye. This surgery takes 1-2 hours.
- vitrectomy, a complex surgery that involves replacing the vitreous, or the clear gel in the center of the eye, with a saline (salt) solution. Removing the vitreous allows for the removal of scar tissue and eases tugging on the retina, which stops it from pulling away. Vitrectomy can take several hours.
Your baby's ophthalmologist will determine and discuss with you which ROP surgery method is best.
Your baby's pediatric ophthalmologist will describe the procedure and answer your questions. This is a good time to ask questions about anything that you don't understand.
ROP surgery is usually performed with a patient under either general anesthesia (medication that induces a deep sleep-like state) or deep sedation (medication that makes the patient unaware of the procedure but not as deeply sedated as with general anesthesia).
Although there is no cutting or stitching involved in laser surgery or cryotherapy, all surgical procedures for retinopathy of prematurity require that the baby be given sedation and pain medication or general anesthesia.
Laser surgery and cryotherapy are usually done at the child's bedside with sedation and pain medication. Because scleral buckle and vitrectomy surgeries require general anesthesia, they are done in an operating room. For all procedures, your baby's breathing and heart rate will be closely watched during the surgery.
Your child will receive eye drops to dilate the pupil(s) before each procedure. During the surgery, a tool called an eyelid speculum will be gently inserted under the eyelids to keep them from closing.
The eye will be covered with a patch after scleral buckling and vitrectomy, but not after laser or cryotherapy. Whether a hospital stay is required will depend on the child's medical condition and age at the time of surgery.
Caring for Your Child
If admission to the hospital isn't necessary, you'll be able to take your child home about an hour after the procedure. Follow-up care for ROP surgery includes giving your child eye drops (to prevent infection) for at least a week.
To make sure the eyes are healing properly and that ROP hasn't returned, eye exams should be scheduled based on instructions from the ophthalmologist. This is usually every 1-2 weeks. For scleral buckling, the ophthalmologist must examine the buckle every 6 months to account for your child's growing eye.
The goal of surgery for retinopathy of prematurity is to stop the progression of the disease and prevent blindness. Although ROP surgery has a good success rate, not all babies respond to treatment. Up to 25% of babies who have ROP surgery might still lose some or all vision.
Keep in mind that for all types of ROP surgery, a degree of your child's peripheral (side) vision will be lost. And even if the ROP has stopped progressing, vision still can be affected.
Since some vision loss and complications can occur, any child who has had ROP surgery should have regular, yearly eye exams well into adulthood.