The risk associated with medical imaging procedures refers to possible long-term or short-term side effects. Most imaging procedures have a relatively low risk. Plus, hospitals and imaging centers practice ALARA (As Low As Reasonably Achievable). This means they make every effort to decrease radiation risk. It is important to remember that a person is at risk if the doctor cannot accurately diagnose an illness or injury. Therefore, it could be said that the benefit from medical imaging (an accurate diagnosis) is greater than the small risk that comes with using it. The 12 ct scans that you have taken is likely to have been done over a long duration of time.