However, it is important to realise that most of these abnormalities are harmless.
The study, which was carried out in Rotterdam on healthy volunteers, and which was led by Dr Meike Vernooij, an associate professor of radiology at the Erasmus MC University Medical Center in Rotterdam, found that 7.2% of the MRIs showed evidence of a brain clot, 1.8% had cerebral aneurysms, and 1.6% had benign brain tumours.
The brain clots were too small to cause symptoms and seemed to be more common in older people. However, aneurysms were as common in younger people as they were in older people. Most of the aneurysms detected were so small that no follow-up treatment was required.