R.O.P.

Known then as retrolental fibroplasia, it is now called retinopathy of prematurity, or R.O.P.

While in training, Dr. Patz observed 21 infants who had developed severe R.O.P. after receiving continuous oxygen therapy delivered through a cone made from folded X-ray film.

Four of the children showed a narrowing of the blood vessels in the retina that seemed to lead to R.O.P.

At the time, doctors were puzzled about why R.O.P. had quickly become the most common cause of childhood blindness in the United States and other countries, counting among its victims Stevie Wonder.

In the first report on the test, in 1952, the research team found that 7 of 28 infants receiving high doses of oxygen experienced severe R.O.P., compared with none in the group receiving low doses.