Retinopathy of prematurity (ROP) is a disease in which aggressive new blood vessels form (neovascularization) in the retina that can lead to blindness in premature infants of low birth-weight and possibly progress to retinal detachment. Dr Ann Ranelle, a specialist in pediatric ophthalmology, will monitor high risk premature infants during their stay in a neonatal care unit.
Retinopathy of Prematurity (ROP) in Premature Infants
Retinopathy of prematurity is a condition that affects premature infants. Retinopathy of prematurity can potentially blind patients due to abnormal developments in retinal blood vessels. The retina is the inner part of the eye that receives light and converts it into visual messages, which it then sends to the brain. In premature babies, the blood vessels can grow abnormally, and the condition can cause the retina to pull away or fully detach from the wall of the eye causing blindness. Most cases of retinopathy of prematurity are resolved without any permanent damage to the retina, however, babies at highest risk of this condition are those that are born before the 31 week mark.
How many infants suffer from ROP?
Of the 3.9 million babies born in the USA each year, 14,000 will suffer from ROP to differing degrees. 90% of these infants affected by ROP will only suffer mildly from the condition. The remaining 1,100-1,500 infants will undergo medical treatment for a severe case of ROP and a further 400-600 infants will become legally blind.
Diagnosis of Retinopathy of Prematurity (ROP)
Pediatric ophthalmologists who are skilled and experienced in infant evaluation will test the eyes. The examination will require drops that dilate the pupils. Due to the high rate of infants suffering from retinopathy of prematurity, ophthalmologists now conduct this test on any infant under the 31 week gestational age or weighing less than 3.3 lbs.
How is retinopathy of prematurity described?
ROP is first described by the location in the eye (the zone), the severity of the disease (the stage) and then by the appearance of the retina vessels.
Stage 1: Demarcation line showing differentiation between normal and premature retina
Stage 2: Retina shows a ridge with height and width
Stage 3: Growth of new abnormal blood vessels
Stage 4: Blood vessel growth is severely abnormal and the retina is partially detached
Stage 5: Complete retinal detachment occurs
As retinopathy of prematurity worsens, the blood vessels may swell and become twisted.
Treatment for Retinopathy of Prematurity
At a certain stage of severity, retinopathy of prematurity poses a great enough risk for permanent vision loss that it warrants the option of laser treatment. In most cases, the laser treatment for ROP causes the abnormal blood vessels to disappear and resolves the disease entirely. However, there are cases where, despite best practice, the ROP worsens and the retina eventually pulls away from the back of the eye. In this case, one of two procedures can be completed:
- Vitrectomy: Surgery to remove an amount of the vitreous humor (clear gel between the lens and retina of the eyeball) from the eye
- Scleral buckle: A procedure to repair a full retinal detachment where a scleral buckle can be used to close the gap
There is some significant development in medications that can stunt the growth of abnormal blood vessels, which are usually suggested as an addition or alternative to laser treatment. Research on the use of these medications for retinopathy of prematurity is still being conducted.
Postoperative Treatment for Retinopathy of Prematurity
After surgery for retinopathy of prematurity, it is important in all circumstances that eye exams are continued after discharge from the hospital, especially when the ROP has not been resolved prior to hospital discharge.
Premature infants are also at risk of amblyopia (lazy eye), strabismus (eye misalignment), the need for glasses and cortical visual impairment (a problem in brain to eye function). In light of this, it is important for all premature infants to have long-term care and check-ups with a pediatric ophthalmologist.