How are mr scan and a ct scan different?

Contrast difference: Ct uses a combination of xrays shot from multiple directions to look at differences in tissue density. Mri uses strong magnetic fields instead of xrays to differentiate tissues and gives much better contrast than ct. Ct is typically used in the acute setting to see if there is blood or major abnormalities. Mri is a more specific exam to differentiate abnormalities such as stroke or tumor.