A CT scan, which is used for imaging and diagnosis throughout the body, exposes a patient to at least 150 times the level of radiation generated from a single chest x-ray. America's National Cancer Institute has estimated that the scans are responsible for around 29,000 new cases of cancer every year in the US.
Researchers at Stanford University analysed blood samples of 67 patients who had had a CT scan for their heart problems. All the samples showed DNA damage and cell death, which repaired in most cases. But a small percentage failed to repair and died, they found. The results could well have been worse in patients who have had multiple scans.
Although CT scans provide a useful role, radiologists should use lower doses, have newer and better machines and technology, and give patients some protective covering, the researchers say.
(Source: Stanford University Medical Centre)