You're confusing CT scans with conventional x-ray images. CT scans deliver the radiation equivalent of hundreds of conventional x-ray images. The radiation dose is high enough to epidemiologically significant (meaning higher cancer rates in people who have been scanned, especially children).
Believe me, I'm not confusing them - I just think it's significantly less risky than the parent does. And yes, there can be higher cancer rates in people who have a _lot_ of CT scans done e.g. because of a serious illness.
