A prevailing theory is that the immature retina produces a chemical that stimulates growth of blood vessels. Why the ailment does not develop earlier than a month alter birth is not well understood. ROP is the new name for what was called retrolental fibroplasia about 30 years ago. At that time, doctors detected the condition in its most severe form, alter the retina had detached. Doctors also discovered that blindness resulted from a baby's being given excessive oxygen.
Doctors still believe that oxygen plays a role but they can better control the amount.
And they know that laser and freezing can prevent the retinal detachment. The test to detect infants whose eyes show the most severe, abnormal growth patterns begins with a drop of a dilating drug in each eye. An hour later, the ophthalmologist adds a drop of local anesthetic to minimize the infant's discomfort during the examination. Looking through an ophthalmoscope, Dr. Coats determines the maturity of the retina by examining the optic nerve, which is a direct extension of the brain, and other areas. Then he looks at the blood vessels, studying their width and growth pattern and looking at how far they have spread.