Do brain MRI's cause dangerous radiation exposure? Why or why not? Dexa Testing?

Question

How does an MRI differ from things such as DEXA testing? Thanks.

Answer 1

MRIs do not use ionizing radiation, but a magnetic field and RF pulses. So there is ZERO exposure to radiation involved. MRIs are used to image nearly every body part, from the head to the feet.

A DEXA is a specialized imaging study used ONLY to dermine a person's risk of osteoporosis. It uses a very low level of radiation to get an image of the spine and hip (sometimes the wrist). The images are not diagnostic (for example, to try to figure out why your hip or back hurts). A computer uses this image to determine a person's bone density. Any time you see an imaging technologist sit in the room, without a lead vest/apron, you can be assured that the dose is very low!

The following website shows doses from different x-ray studies. A single DEXA image will expose a patient to about 2.5 milliSieverts. A chest x-ray is between 10-50 millisieverts and an examination of the lower back is 1,300 - 2,700.

http://homepage.mac.com/kieranmaher/digrad/DRPapers/DEXA_Dosimetry.html#BMD

Answer 2

MRI uses a magnetic field to take the picture. While it doesn't use radiation, you should avoid exposure to it if you are pregnant as the magnetic pull can harm your unborn baby(I had to miss my son's MRI on the day of his neurosurgery to remove a brain tumor due to that and it ripped my heart out not to be with him in there, as that is the last place we could see him before the operation took place. I'm not totally sure was DEXA testing is, but there's a test used to look at things closer where they inject a radioactive dye into the person and it highlights the path that they are trying to evaluate. My son also had the radioactive dye injection which I was advised to miss because I was pregnant at the time, but neither hurts worse than the other....it's just the dye injection is a little better at actually isolating the problem where as the MRI gives you a big broad picture.

Answer 3

The MRI is a big magnet that is used to take the pictures. It's best for things like soft tissue injuries such as can occur with arthritis or problems with the nerves. The dexa scan uses radiation but the dosage is much different than what would be used for a CT Scan (another type of x-ray testing).

Answer 4

MRI does not work with radiation. It works with strong magnetic fields. It trys to pull electrons of your body out of their orbit. Electrons will vibrate according to their orbit and where in your body they are. these differences in vibration makes the image of MRI. Magnetic Resonance Imaging.