What is Retinopathy of Prematurity?
Retinopathy of Prematurity (ROP) is an eye condition that affects premature babies, where abnormal blood vessels grow in the retina. If not detected and treated early, it can lead to vision problems or even permanent blindness.
Retinopathy of Prematurity in India: Understanding the Condition and Treatment
When a baby is born too early, the retinal blood vessels have not finished growing. In a full-term pregnancy, the vessels complete their journey to the edges of the retina just before birth. In a premature baby, that process is interrupted. After delivery, in an environment with more oxygen than the womb, abnormal blood vessels can start growing in place of the normal ones. These vessels are fragile. They leak. They can pull on the retina and, in severe cases, detach it entirely.
This is retinopathy of prematurity, or ROP. It affects babies born before 31 weeks of gestation or those weighing less than 1,500 grams at birth. Not every affected baby develops serious disease; mild ROP often resolves on its own as the retina catches up. But a significant proportion of affected infants have disease severe enough to require treatment, and without it, permanent visual impairment or blindness is the outcome.
The condition is classified in five stages based on severity, combined with descriptions of which retinal zone is affected and whether disease is present. Plus disease refers to a pattern of dilated, tortuous blood vessels near the optic disc that signals aggressive vascular activity. When plus disease is present, urgency increases significantly.
The genuinely reassuring aspect of ROP is that when it is caught at the right stage and treated promptly, sight-threatening disease can be halted in the majority of cases. The tragedy is when babies are not screened at all, or when parents do not bring them back for follow-up.
India’s neonatal medicine has advanced considerably over the past two decades. More premature and very-low-birth-weight babies are surviving now than ever before. That progress has a consequence that not everyone anticipated: a larger population of infants at risk for ROP. Published Indian data suggests that between 38% and 52% of screened infants in neonatal units have some form of ROP, with sight-threatening disease present in roughly 5 to 15% of those screened.
The screening infrastructure has not kept pace with the clinical need. Many neonatal units in tier-2 and tier-3 cities do not have a systematic ROP programme. Babies are discharged from the NICU without ever being examined by an ophthalmologist. By the time they arrive at a specialist, weeks or months later, the opportunity for early intervention has passed. Some arrive with retinas already detached.
Stages of Retinopathy of Prematurity
| Stage | Description | Management |
|---|---|---|
| Stage 1 | Thin demarcation line between vascular and avascular retina | Observation; most cases regress spontaneously |
| Stage 2 | Raised ridge at the boundary between vascular and avascular retina | Observation; some cases progress and need monitoring |
| Stage 3 | Abnormal fibrovascular growth extending into the vitreous | Treatment indicated when threshold criteria are met |
| Stage 4 | Partial retinal detachment (4A: fovea spared; 4B: fovea involved) | Surgical intervention required |
| Stage 5 | Total retinal detachment in a funnel configuration | Surgery; prognosis for vision is poor |
| APROP | Aggressive Posterior ROP: rapidly progressing in zone I or posterior zone II | Urgent treatment within 48 hours of diagnosis |
Retinopathy of Prematurity: How Screening and Treatment Work
ROP screening is done with indirect ophthalmoscopy. The baby’s pupils are dilated with drops and the ophthalmologist examines the peripheral retina using a headband-mounted light and a scleral depressor to see the far edges. The examination is done in the neonatal unit or outpatient clinic and findings are recorded by stage and zone.
Indian screening guidelines recommend examining babies with a birth weight below 2,000 grams or a gestational age below 34 weeks. The first examination is timed at 3 to 4 weeks postnatal age or 31 weeks post-conceptional age, whichever is later. How often the baby is re-examined after that depends on what is found.
Laser photocoagulation is the standard treatment for type 1 ROP. The laser is applied to the avascular peripheral retina under general anaesthesia, destroying it and removing the biochemical signal that was driving the abnormal vessel growth. Anti-VEGF injections (bevacizumab or ranibizumab) given directly into the vitreous are particularly effective for APROP and zone I disease, where the response to laser alone can be incomplete. Stages 4 and 5 require surgery: vitrectomy, scleral buckle, or both.
When is ROP Treatment Necessary?
Treatment is indicated for type 1 ROP and for APROP. The definitions come from the International Classification of ROP:
- Zone I, any stage with plus disease
- Zone I, stage 3 without plus disease
- Zone II, stage 2 or 3 with plus disease
- APROP: treatment within 48 hours of diagnosis, no exceptions
ROP produces no symptoms the parents or nursing staff can observe. The baby does not cry differently, does not behave unusually, and does not appear unwell. Screening is the only way to know. If your baby has been in a NICU and you have not been told about an ROP examination, ask the neonatologist today.
ROP Treatment: Step-by-Step Procedure
- Screening scheduled: Based on birth weight and gestational age, the first examination is timed appropriately.
- Pupil dilation: Dilating drops are instilled in the NICU well before the examination.
- Retinal examination: Indirect ophthalmoscopy with scleral depression to visualise the peripheral retina. Findings recorded by stage and zone.
- Treatment decision: If type 1 ROP or APROP is present, treatment is arranged urgently.
- Laser photocoagulation (under general anaesthesia): Laser is applied to the avascular retina through the dilated pupil.
- Anti-VEGF injection (if applicable): Intravitreal injection given under sterile conditions.
- Post-treatment monitoring: Re-examination at 1 week and 2 weeks to confirm regression and catch any reactivation.
How Much Does ROP Treatment Cost in India?
| Procedure | Approximate Cost Range (INR) |
|---|---|
| ROP Screening Examination | ₹500 – ₹2,000 per visit |
| Laser Photocoagulation (both eyes) | ₹20,000 – ₹50,000 |
| Anti-VEGF Intravitreal Injection (per eye) | ₹15,000 – ₹40,000 |
| Vitrectomy for Stage 4 or 5 ROP (per eye) | ₹60,000 – ₹1,50,000 |
Government hospital rates may be substantially lower.
ROP: Post-Treatment Care and Recovery
What to Expect After Treatment?
After laser, the treated retina takes two to three weeks to fully scar and suppress the abnormal vessel growth. The baby’s eyes may look red for a few days. Multiple re-examinations are done during this period to confirm the treatment is working.
After anti-VEGF injection, the abnormal vessels regress quickly, often visibly so within a week. However, the peripheral retina remains avascular after injection alone, which means the follow-up schedule extends further into childhood than after laser. Reactivation of ROP after anti-VEGF is a known phenomenon and is the reason long-term surveillance matters so much for these children.
Post-Treatment Care Tips for Parents
- Bring your baby to every scheduled follow-up examination without exception. ROP can reactivate
- Administer prescribed eye drops exactly as instructed after any procedure
- As your child grows, watch for signs of vision difficulty: not following faces, not making eye contact by 3 months, squinting
- Children with a history of ROP need regular vision assessments throughout childhood. They are at higher risk of myopia, squint, and amblyopia
- Share the full ROP history with every paediatrician and eye care provider your child sees in future
References
Cleveland Clinic. Retinopathy of Prematurity. https://my.clevelandclinic.org/health/diseases/17430-retinopathy-of-prematurity
PMC, NCBI. ROP in India: Epidemiology and Management. 2019. https://pmc.ncbi.nlm.nih.gov/articles/PMC6874220/
EyeWiki, AAO. Retinopathy of Prematurity. https://eyewiki.org/Retinopathy_of_Prematurity
Frequently Asked Questions
Not necessarily. Many premature babies have no ROP at all, and many who do develop it have only mild disease that resolves without treatment. What we cannot predict in advance is which baby will progress to sight-threatening stages. That is why every baby meeting the screening criteria needs to be examined, regardless of how well they appear clinically.
The first examination is typically at 3 to 4 weeks postnatal age, or 31 to 32 weeks post-conceptional age, whichever comes later. Subsequent examinations are scheduled based on what is found at each visit.
The dilation drops cause brief stinging, and the examination using the scleral depressor causes some discomfort. The baby may cry. It is brief, and it is genuinely necessary. The consequences of undetected ROP are far worse than the discomfort of the screening examination.
In the majority of cases treated at the right stage, laser or anti-VEGF therapy arrests the disease and prevents further progression. The final visual outcome depends on how advanced the ROP was at the time of treatment, how promptly treatment was given, and whether any retinal detachment had already occurred.
Many babies who receive timely treatment for type 1 ROP achieve useful vision. The outcome varies significantly with the stage and zone of disease. Stage 4 and 5 ROP carry a poorer prognosis even with surgery. Honest discussions with the treating ophthalmologist are important for setting realistic expectations.
Aggressive Posterior ROP is the most dangerous form. It progresses rapidly and affects the posterior zones of the retina, closest to the macula and optic disc. Treatment must happen within 48 hours of diagnosis. It tends to affect the most premature babies and those with the lowest birth weights.
Yes. Reactivation after laser occurs in a small proportion of cases. It is more common after anti-VEGF injection because the peripheral avascular retina persists and can generate renewed stimulus for abnormal vessel growth. Follow-up is not optional.
Historically, high-dose supplemental oxygen was directly linked to ROP. Modern neonatal care manages oxygen saturation targets carefully to balance the baby’s respiratory needs against retinal risk. Being born prematurely is the fundamental risk factor, and even babies with carefully managed oxygen levels can develop ROP if they are premature enough.
Children with a history of ROP are at higher risk of myopia, squint, amblyopia, and retinal detachment in later childhood and adult life. Regular ophthalmic follow-up through the school years is important, not just in infancy.
Yes. If your baby has been or is currently in a NICU, contact Vasan Eye Care directly or ask your neonatologist to arrange a referral.
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References
Cleveland Clinic. Retinopathy of Prematurity. https://my.clevelandclinic.org/health/diseases/17430-retinopathy-of-prematurity
PMC, NCBI. ROP in India: Epidemiology and Management. 2019. https://pmc.ncbi.nlm.nih.gov/articles/PMC6874220/
EyeWiki, AAO. Retinopathy of Prematurity. https://eyewiki.org/Retinopathy_of_Prematurity
