Could an X- ray damage your
child's future brainpower?
Mail Jan2, 2004
X-RAYING the heads of children could damage their brainpower when they grow up, according to research.
The study is the first to suggest that medical X-rays to the head could harm the development of the brain in later life.
It found that adults whose brains were exposed to ionising radiation during infancy grew up to be less intelligent with fewer educational achievements than those who had not.
The study also has implications for children today, who are increasingly given CT scans to check for injury after a minor head trauma.
A CT scan uses a computer linked to an X-ray machine to create detailed images of the inside of the body.
The research shows that one CT scan contains enough radiation to adversely affect a child's intellectual potential.
Professor Per Hall, who carried out the study at the Karolinska Institute, Stockholm, Sweden, said the findings are 'alarming'.
He said they are based on children who had head X-rays before the age of 18 months. But he feared there might be damaging effects even in older children. 'There is no doubt CT scans can be a fantastic lifesaving tool that will be helping doctors for years to come and we are not saying they should never be used,' he added.
'However, the use of CT scans has become sloppy. They are routinely used for minor cases of head trauma, possibly for legal and financial considerations, because we have not been aware of the potential risks and this practice needs to be re-evaluated.
'If a baby falls off his nappy-changing table, or a two-year-old comes off a bike and bangs her head, but there is no loss of consciousness, vision problems or vomiting, then it may be prudent not to use a CT scan.
'It is a different matter if the child is knocked unconscious and is sick.'
The study involved 3,094 men who had received radiation therapy before the age of 18 months between 1930 and 1959 for minor birthmarks called haemangioma.
At the time, X-ray therapy was recommended even though most of these birthmarks spontaneously disappear. At the ages of 18 and 19, the intellectual capacity of the men was tested and their attendance at high school recorded, says a report in today's British Medical Journal.
The proportion of boys who attended high school fell as the amounts of radiation they were exposed to on the front and back of the brain increased.
Those exposed to head irradiation were 50 per cent less likely to stay on at school, with one in three boys not exposed to head X-rays attending secondary school compared with one in six of those who had.
Boys who had received head X-rays were less able at intelligence tests showing learning ability and logical reasoning.
Professor Hall said that, on | average, children in the study were exposed to the same amount of radiation contained in a single CT scan.
He called for radiologists to use the lowest possible dose when taking CT scans of children.
Manufacturers of CT scanning equipment should also respond to the findings, he added.
'Breast X-ray machines now use 50-100 times less radiation than they used to, because the potential dangers to women having regular mammograms had been recognised' he said.