Complex heart tests raise cancer risk

Radiation from standard X-rays do not significantly raise cancer risks for young children, in general, but children undergoing more complex procedures with higher radiation have higher risks, says a study.

"Cancer risk overall is relatively low, but we hope that this awareness will encourage providers to limit radiation exposure in children, when alternative procedures can offer the same benefit with less radiation," said Jason Johnson, an assistant professor at the University of Tennessee Health Science Center in the US.

Researchers reviewed medical records to find the most common imaging procedures, calculated how much radiation organs absorb during each procedure and then used a report from National Academy of Sciences in the US to analyse lifetime cancer risks based on the amounts of each procedure's exposure.

lifetime cancer risk increases ranged from 0.002 percent for chest X-rays to 0.4 percent for complex CT scans and cardiac catheterisations.

The study appeared in the journal Circulation.