Premature babies born with severe
forms of the potentially blinding eye condition retinopathy of prematurity (ROP) should be treated promptly after diagnosis because
they continue to benefit from early therapy well into their preschool years, according
to a nationwide study conducted at Johns
Hopkins Children’s Center and 25 other pediatric hospitals.
ROP, a disorder affecting about 15,000
U.S. babies each year, is marked by abnormal growth of blood vessels in the eyes
that causes scarring and detachment of the light-collecting retina.
The new study, to appear online on
April 12 in the Archives of Ophthalmology, builds
on research published by the same group in 2003, which found that earlier
surgery in infants to remove abnormal blood vessels improved outcomes to age 2
in the youngest children with severe forms of the disease, defined by dilated
blood vessels in the retina growing in a twisted pattern. Such children are
treated with laser surgery or cryotherapy (freezing), both of which involve
destroying the chaotically growing blood vessels to prevent further retinal
damage and vision loss. Until the first study, however, the standard treatment
for such infants was to hold surgery until the risk of retinal detachment
reached 50 percent, but with early treatment, children with severe forms of the
disease undergo surgery before they reach the 50 percent threshold.
In the second phase just reported,
the researchers followed 370 of the original 401 patients through age 6 and not
only confirmed the early findings, but also showed that high-risk children
continue to do well at age 6 if they received the early treatment.
The team also confirmed results from
the first study that children with milder forms of ROP do not benefit from
early treatment and more than half improve without it. These findings, the
researchers say, underscore the importance of careful monitoring rather than
aggressive treatment of those low-risk children.
“Our new findings have answered the
most vexing question — do the benefits persist — after the original study and
in doing so further highlight how critical it is to tailor treatment decisions
to each individual patient’s risk and overall medical condition,” said study
X. Repka, M.D., of the Johns
Hopkins Wilmer Eye Institute and deputy
director of ophthalmology at Johns Hopkins Children’s.
In the follow-up study, nearly 75
percent in the high-risk group had good visual acuity after early treatment,
compared to 67 percent among those who received standard treatment. Also, 15
percent of high-risk eyes treated under the standard protocol had substantial retinal
damage, compared with only 9 percent of high-risk eyes treated early.
These findings should help pediatric
ophthalmologist move away from one-size-fits-all medicine toward more
individualized therapy, the investigators say.
long-term study has given clinicians evidence that infants with ROP should be treated with different strategies
based on an infant’s risk for a severe form of the disease, which can be
determined through an exam at the bedside,” said lead investigator William V.
Good, M.D., of Smith-Kettlewell Eye Research Institute in San Francisco.
caution that not all children who qualified as high risk benefited from early
therapy, and some of them developed vision loss despite their treatment. The
finding emphasizes the critical importance of ROP
prevention, the researchers say, because even with proper and timely treatment,
some children do not do well.
The majority of babies born with ROP have a mild form of the disease that does not
require treatment, but those with more severe forms tend to develop visual
impairment, even blindness. Up to 600 infants become legally blind each year in
the United States because of ROP,
the investigators estimate.
The research was funded by the National Eye Institute.