Retinopathy of Prematurity
Understanding Retinopathy of Prematurity
Retinopathy of prematurity is a disease that affects the retina, the light-sensitive tissue at the back of the eye. In premature babies, the blood vessels that supply the retina may not finish growing properly. This can lead to abnormal blood vessel growth and, in severe cases, scarring or retinal detachment.
The condition occurs because the retina's blood vessels normally finish developing during the last few weeks of pregnancy. When a baby is born early, this development is interrupted.
In the womb, a baby's retinal blood vessels grow from the center of the retina outward toward the edges. This process usually completes around the time of full-term birth. When a baby is born prematurely, the blood vessels have not yet reached the outer areas of the retina.
After birth, these vessels may continue to grow normally, or they may grow abnormally. Abnormal growth can cause the vessels to become twisted, leaky, or form scar tissue that pulls on the retina.
We classify ROP into five stages based on how severe the abnormal blood vessel growth has become. Stage 1 is the mildest form, where a thin line separates the normal retina from the area without blood vessels. Stage 2 shows a raised ridge at this boundary.
Stage 3 involves abnormal blood vessels growing from the ridge into the center of the eye. Stage 4 means the retina has begun to detach partially, and Stage 5 indicates complete retinal detachment. Early stages often improve without treatment, but advanced stages require prompt intervention.
Plus disease is a term we use to describe additional signs of severe ROP. When plus disease is present, the blood vessels in the central retina become very dilated and twisted. This indicates that the ROP is more aggressive and may need treatment sooner.
- Plus disease can occur at any stage of ROP
- It signals increased risk of rapid progression
- Aggressive posterior ROP is a rare, fast-moving form that appears in the back of the retina
- These findings often change our treatment timeline
ROP can develop in one eye or both eyes, though it typically affects both. The severity may differ between the two eyes. One eye might have mild ROP that resolves on its own, while the other eye may progress to a stage that requires treatment.
We examine both eyes carefully during each screening visit to monitor how the condition is developing in each eye separately.
Risk Factors and Who Needs Screening
The biggest risk factors for ROP are being born very early and having a very low birth weight. Babies born before 31 weeks of pregnancy or weighing less than 3 pounds 5 ounces at birth have the highest risk. The earlier and smaller a baby is at birth, the greater the chance of developing ROP.
These babies have the least mature retinal blood vessels, giving them more time and opportunity for abnormal vessel growth to occur.
Premature babies often need extra oxygen and other intensive care treatments to survive and thrive. While these treatments are life-saving, they can contribute to ROP development. Oxygen levels that are too high or fluctuate significantly may play a role in abnormal vessel growth.
- Breathing problems and lung disease increase risk
- Blood transfusions and anemia may be contributing factors
- Infections and other complications can raise the likelihood of ROP
- Overall health instability in the NICU is associated with higher rates
We recommend ROP screening for all babies born at or before 30 weeks gestational age. We also screen babies born weighing 2.75 pounds or less. In some cases, babies who fall slightly outside these guidelines may also need screening if they had an unstable medical course.
Your baby's neonatologist and our eye doctor will work together to determine if screening is appropriate based on your baby's specific situation.
The first ROP screening exam typically happens between 4 and 6 weeks after birth, or at 31 weeks postmenstrual age, whichever comes later. Postmenstrual age refers to the gestational age at birth plus the number of weeks since birth. The timing is chosen to catch ROP when it first starts to develop.
Starting too early would not show meaningful changes, while waiting too long could miss the window when treatment is most effective.
Screening and Diagnosis
During an ROP screening exam, we use special eye drops to dilate your baby's pupils so we can see the entire retina. We gently hold the eyelids open with a small instrument and use a light and magnifying lens to examine the retina thoroughly. The exam takes about 10 to 15 minutes.
While the exam is not harmful, some babies find it uncomfortable. The NICU team may give your baby pain relief medication, a pacifier, or sugar solution to reduce discomfort during the examination.
Our eye doctor carefully examines each zone of the retina, looking for the line between the vascularized area and the avascular area where blood vessels have not yet grown. We assess the location, stage, and extent of any abnormal findings. We also check for plus disease by examining the blood vessels near the optic nerve.
- We map the entire retina in a systematic pattern
- We document the clock hours affected by abnormal vessels
- We may use digital imaging to record findings for comparison
- We assign a classification that guides the follow-up schedule
After the exam, we will explain what we found using the zone, stage, and plus disease classification system. Zone 1 is the central retina, Zone 2 is the middle area, and Zone 3 is the outer edge. The zone tells us where the abnormal growth is located, which helps predict how serious it might become.
The stage and presence of plus disease tell us how severe the condition is right now. We will discuss whether your baby needs treatment, more frequent monitoring, or can continue with routine screening.
The frequency of follow-up exams depends on what we find during each visit. If the retina looks normal or shows only mild changes, we may recheck every 1 to 2 weeks. If we see more concerning findings, we may examine your baby more often, sometimes every few days.
We continue screening until the retinal blood vessels have fully grown to the edge of the retina or until we determine that treatment is needed. Even after ROP resolves, some babies need ongoing eye exams to watch for other vision problems.
Treatment Options for Retinopathy of Prematurity
We recommend treatment when ROP reaches a threshold level where the risk of vision loss becomes significant. This typically happens at Stage 3 ROP in Zone 1 with plus disease, or Stage 2 or 3 in Zone 1 without plus disease in certain configurations. We also treat aggressive posterior ROP promptly.
The goal of treatment is to stop the abnormal blood vessel growth before it causes retinal detachment. Treatment is most effective when performed at the right time, which is why close monitoring is so important.
Laser photocoagulation is a proven treatment for ROP that has been used successfully for many years. During this procedure, we apply laser energy to the avascular part of the retina, the area where blood vessels have not grown. This reduces the retina's oxygen demand and stops the abnormal vessel growth.
- The procedure is performed in the NICU or operating room
- Your baby receives anesthesia or sedation for comfort
- We place hundreds to thousands of tiny laser spots in the avascular retina
- The treated area will not develop normal vision, but the central retina is preserved
- Results are usually seen within days to weeks
Anti-VEGF injections are a newer treatment option that became more common in the 2010s and continues to be refined. We inject a medication into the eye that blocks a protein called vascular endothelial growth factor, which drives abnormal blood vessel growth. This allows the normal vessels to continue developing.
As of 2025, we use anti-VEGF therapy selectively, most often for Zone 1 ROP where preserving peripheral vision is especially valuable. The injections may allow more normal vessel growth to continue compared to laser, but they require careful long-term follow-up to watch for reactivation of ROP.
When ROP progresses to Stage 4 or 5 with retinal detachment, we may recommend surgery to try to reattach the retina. A vitrectomy involves removing the vitreous gel and scar tissue pulling on the retina. A scleral buckle is a band placed around the eye to help the retina settle back into place.
These surgeries are complex and are typically reserved for cases where earlier treatments were not possible or did not succeed. Even with surgery, the visual outcome in advanced ROP can be limited, which is why early detection and treatment are so important.
Each treatment option has benefits and considerations. Laser treatment has a long track record of success and does not require ongoing monitoring for reactivation as frequently. Anti-VEGF injections may preserve more peripheral retina and peripheral vision, but the medication can enter the bloodstream, and there are theoretical concerns about effects on other developing organs.
We may recommend one approach over another based on the zone and severity of ROP, your baby's overall health, and the ability to ensure close follow-up. In some cases, we might use a combination of treatments.
Recovery, Follow-Up Care, and Long-Term Outlook
After laser treatment, the eye may appear red or swollen for a few days. Your baby might receive eye drops or pain medication to keep them comfortable. After anti-VEGF injection, the eye typically looks normal within a day or two. Most babies recover well from either procedure and can resume normal activities quickly.
We will examine your baby shortly after treatment to make sure the ROP is responding appropriately. It can take several weeks to see the full effect of treatment.
After treatment, we monitor your baby's eyes closely to ensure the ROP is regressing and not progressing. For laser-treated eyes, we typically recheck weekly at first, then space out visits as the retina stabilizes. For injection-treated eyes, we may examine your baby every 1 to 2 weeks for several months because there is a risk of ROP reactivation.
- Early exams confirm the treatment is working
- We watch for any new areas of abnormal vessel growth
- After ROP resolves, exams continue on a less frequent schedule
- Long-term follow-up is needed throughout childhood and beyond
Even when ROP treatment is successful and the retina remains attached, children who had ROP face higher risks for other eye problems. These include an increased chance of nearsightedness, farsightedness, and astigmatism. Strabismus, or eye misalignment, is also more common in children who had ROP.
There is also a higher risk of retinal problems later in life, such as retinal tears or detachments during adolescence or adulthood, even many years after the ROP has resolved.
We recommend that all children who had ROP, whether treated or not, continue regular eye exams throughout childhood. We check for refractive errors such as nearsightedness, farsightedness, and astigmatism, which can develop or change over time. If we find significant refractive errors, we may prescribe glasses.
Amblyopia, or lazy eye, can occur if one eye sees more clearly than the other or if the eyes are not aligned properly. Early detection and treatment with glasses, patching, or other therapies can help maximize your child's vision development.
As your child grows, certain symptoms should prompt you to seek eye care right away. These include a sudden change in how the eyes look or move, a white reflection in the pupil instead of the normal red reflex, eyes that cross or drift more than usual, or signs that your child is not seeing well.
- Contact us if your child complains of flashing lights or floaters
- Sudden vision loss or a curtain over part of the vision requires immediate attention
- Eye pain, redness, or discharge that does not improve should be evaluated
- Any concern about your child's vision or eye health warrants a phone call to our office
Frequently Asked Questions
The screening exam itself does not hurt the eye, but babies often dislike having their eyes held open and the bright light shining in. The NICU staff will do everything possible to keep your baby comfortable, including using pain-relieving measures and allowing you to comfort your baby immediately afterward.
Yes, many cases of ROP, especially milder stages, improve and resolve without any treatment as the retinal blood vessels finish growing normally. About 90 percent of babies with ROP have mild disease that does not require intervention. Only the most severe cases need laser, injections, or surgery.
No, ROP does not always cause vision loss. When ROP is mild and resolves on its own, or when more serious ROP is caught early and treated successfully, many children develop good functional vision. However, all children who had ROP should be monitored long-term because they have higher risks of vision problems even with favorable ROP outcomes.
Children with a history of ROP have higher rates of needing glasses than children born at full term. Nearsightedness is particularly common. Regular eye exams will help us detect refractive errors early so we can prescribe glasses if needed to support clear vision and healthy visual development.
Unfortunately, there is no way for parents to prevent ROP, as it is related to prematurity and the medical care needed to keep premature babies healthy. The best thing you can do is make sure your baby receives all recommended ROP screenings and follow-up exams so that any problems are caught and treated at the right time.
Getting Help for Retinopathy of Prematurity
If your baby is at risk for ROP or has been diagnosed with this condition, our eye doctor is here to provide expert screening, monitoring, and treatment as needed. We work closely with your baby's NICU team to ensure your child receives timely, coordinated care. Please do not hesitate to ask questions or share concerns at any point during your baby's eye care journey.