It’s a mystery. An eye disease known as retinopathy of prematurity (ROP) can lead to permanent blindness if untreated. However, there are significant differences in how often Norwegian hospitals actually provide this treatment.
“These differences between hospitals are inexplicable,” says Dordi Oosteng.
Osteng is a professor in the Department of Neurology and Exercise Sciences at the Norwegian University of Science and Technology (NTNU). In fact, the proportion of newborns who develop this condition should be the same across the country.
There should be no difference between hospitals in the proportion of premature infants who develop the disease and therefore require treatment. But there is. ”
Dordi Ostenng, Professor, Department of Neurology and Exercise Sciences, NTNU
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But the unexplainable often requires thorough investigation before it becomes explainable, and that is exactly the kind of study that Osteng and colleagues conducted.
Norwegian ophthalmologists conducted tests to find out whether these may be the cause of regional differences in eye disease among premature babies.
Are there differences in ophthalmologists depending on the hospital? And is that variation simply due to ophthalmologists deciding that the eye disease is so serious that it requires treatment?
“In our study, Norwegian ophthalmologists were tested to find out whether Norwegian ophthalmologists were responsible for regional differences in eye disease in premature infants,” Åsteng said.
All 15 ophthalmologists in Norway who examine children and decide whether to treat them participated in the study. The question was whether the specialists at some hospitals were more strict than others.
First, a little bit about the state.
Stevie Wonder had this disease
“Incubator blindness” is an old name for an eye disease. Today, experts most often use the abbreviation ROP, which stands for retinopathy of prematurity. This condition usually affects premature babies.
“The blood vessels in the retina that line the inside of the eye are not fully developed in premature babies. The earlier a baby is born and the more treatments such as oxygen are given, the greater the risk that the blood vessels will grow incorrectly,” said Thora Sand Moken, a professor in the Ophthalmology Research Group.
Stevie Wonder was born early. He was an incubator baby in the early 1950s when he went blind due to this very eye disease.
“Fortunately, very few children today go blind because they are examined weekly by a specialist ophthalmologist and treated if they are at risk of vision loss,” Moken says.
Most treatments where doctors were the most strict
However, it is important to get diagnosed. Therefore, a thorough examination by a hospital specialist is required.
“Doctors logged on to the website and completed tests that our colleagues in the United States helped us prepare,” Oosteng said.
Therefore, when the treatment was the most common, doctors made this diagnosis less often.
The result was a very unexpected answer.
“The results showed that the local ophthalmologists who treated the most children made the most limited diagnoses of ROP that required treatment,” Oosteng said.
Therefore, when treatments were most common, doctors made diagnoses less frequently.
“This is exactly the opposite of what you would expect if ophthalmologists overtreated children,” Oosteng says.
So, what is the reason for these differences between hospitals?
Is it because of survival rates or lung disease?
“Unfortunately, we don’t know the answer yet,” Oosteng said, but he said there are several possible reasons.
Survival rates may vary depending on the hospital.
“We know that premature babies are more susceptible to the disease. As a result, a higher proportion of children have eye disease and more severe eye disease that requires treatment may occur,” she says.
Other risk factors include infections and lung diseases that require oxygen therapy. The incidence and treatment of these illnesses may vary between hospitals. Research groups are still working to figure this out.
Kyrre Moljord is a PhD student participating in a project launched by the group together with Professor Olaf Dammann. Daman is an epidemiologist at Tufts University in Boston and a visiting professor at NTNU.
looking for other opportunities
“The next step is to scrutinize the data collected on children at the Norwegian Neonatal Network,” Oosteng said.
This network contains records of all neonatal illnesses and treatments received from health care providers.
“We hope to find more answers this year. What we now know is that the differences are probably not due to variations in the diagnosis of ROP that requires treatment,” Oosteng said.
sauce:
Norwegian University of Science and Technology (NTNU)
Reference magazines:
Austeng, D. others. (2026). Interobserver variability is unlikely to explain regional differences in retinopathy of prematurity in Norway. acta ophthalmology. DOI: 10.1111/aos.70146. https://onlinelibrary.wiley.com/doi/10.1111/aos.70146

