I learned this from watching House. I am certain that it's true, but I also kind of wonder how much backpressure there is against this kind of thing because the scanners are also insanely expensive to run per minute.
The backpressure on x-rays is because dosing yourself with radiation on a regular basis is a really great way to generate health problems in the course of trying to find some. There's a reason x-ray operators and anyone in the room with the patient get given lead lined aprons to wear while the machine is active.