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“We struggle so hard to keep these babies alive and then they lose their sight. It’s really a tragedy,” said Dr. Kenneth Wright, director of the DEF Infant’s and Children’s Program.

Ironically, better technology is behind the rise of ROP. Hospital intensive care units have gained the technical ability to sustain very low birth-weight babies. Assisted fertilization procedures have also increased the number of multiple, low-weight births. Thankfully, Dr. Wright and the team at the Cedars-Sinai Neonatal Intensive Care Unit appear to have found a low-tech solution for a high-tech problem.

Preliminary study data indicate that too much oxygen may be the main cause of ROP in premature infants. Results from this concept were originally presented in a paper published in Pediatrics in 2003. This landmark publication was co-authored by Dr. Wright and supported by DEF. Results showed that severe ROP could be dramatically reduced by carefully controlling the oxygen dosage.

“Premies really are not babies, they are fetuses out of the womb,” Wright said. “By recreating womb-like oxygen levels, we can facilitate more appropriate eye growth.”

Conventional wisdom tells many hospitals to feed enough oxygen to babies to turn their skin pink. Doctors still worry that lower oxygen levels could cause insufficient development of the lungs and other organ systems, as well as cerebral palsy.

However, for 6 years Cedars-Sinai Medical Center has been delivering oxygen levels to premies that are 5 to 15 percent below what a normal person should receive. As a result, the hospital has seen ROP decline from 7.6 to 0.6 percent. Only three babies have had severe ROP requiring laser surgery, and no babies were blinded.

Blood vessels in the retina and other body tissues of premature babies are not fully developed. Sudden exposure to higher levels of oxygen aborts the normal growth of those vessels, according to Wright.

After a while, retinal tissue with no blood vessels sends out molecular signals demanding blood vessel growth. Instead of normal growth, however, fragile blood vessels sprout inappropriately, starting a cascade of events that can lead to retinal detachment and blindness.

“Once premies lose their sight in this process, they don’t get it back,” Wright said. The best that doctors can do is try to save what sight is left by using lasers that can stop aberrant vessel growth. About half of babies treated this way end up legally blind.

Wright said that at Cedars-Sinai, no statistically significant differences have been observed in mortality or in cerebral palsy among the children getting low oxygen compared with those babies treated with standard levels. However, he is seeking approval to conduct a study to prove this result by collecting data about the developmental outcomes of babies treated with the protocol some two years ago.

Since Wright helped start the low-oxygen protocol at Cedars-Sinai Medical Center, the County Hospital at USC, Good Samaritan Hospital and Singapore National Hospital have adopted it with very good results. Many more hospitals are following suit. Many doctors still believe, however, that a highly oxygenated, pink baby is less susceptible to developmental problems.

For now, Dr. Wright suggests that parents ask hospitals if they will follow a low-oxygen protocol in the interests of preventing ROP. “We haven’t completed all our studies,” says Wright, “but at this point it appears that an ounce of prevention is worth any known treatment for ROP.”