Retinopathy prematurity (ROP) is a blinding disease of premature babies where abnormal blood vessels grow in the developing retina. (the innermost light sensitive layer of the eye)
The blood vessels grow along the surface of the developing retina and reach termination in a full term baby. In babies born prematurely the growth is incomplete and the vessels may grow abnormally. These abnormal blood vessels are fragile, and can bleed easily. Repeated bleeding can cause scarring. As this scar tissue contracts it pulls on the immature retina leading to retinal detachment
ROP is asymptomatic. Blindness in the infant is often recognized by the parents only at the age of 6-8 months or sometimes even later. So screening is very important for premature babies.
Less severe forms of ROP may be associated with:
It is categorized into 5 stages: ROP goes through 5 stages of increasing severity. Stage 1 and 2 may sometimes regress. Stage 3 (sight threatening ROP) usually needs treatment. Stage 4 and 5 are the most severe and often have poor visual outcomes despite treatment. Plus disease is a term that indicates a more severe ROP.
The infant retina is divided into 3 zones from inward out with Zone 1 being most critical for vision, zone 2 requiring treatment in stages 3 and beyond, and zone 3 disease usually requiring no treatment.
Laser photocoagulation is the mainstay of treatment of sight threatening ROP. Stage 3 and Plus disease ROP requires treatment .Stages 4 and 5 require surgery either scleral buckling or vitrectomy. In select cases of Zone 1 disease especially in very sick babies who cannot tolerate laser photocoagulation injection of anti VEGF agents may be given.
Babies born earlier than 34 weeks and weighing less than 2 kg should be screened for ROP by the first 28 days of life. This is usually done by an ophthalmologist trained in the same. Serial examination at weekly or two weekly intervals are done till the growth is complete or to detect if sight threatening ROP is developing
Written by: Dr. Jyothsna Rajagopalan – Consultant Ophthalmologist, Coles Road
3rd Floor, Buhari Towers, No.4, Moores Road, Off Greams Road, Near Asan Memorial School, Chennai – 600006, Tamilnadu