What is the diffrence in a MRI, a x-ray and a cat scan?

Question

Not how they work but what they do

Answer 1

Magnetic resonance imaging (MRI) is a noninvasive, usually painless medical test that helps physicians diagnose and treat medical conditions.

MR imaging uses a powerful magnetic field, radio waves and a computer to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. The images can then be examined on a computer monitor or printed. MRI does not use ionizing radiation (x-rays).


CT imaging uses special x-ray equipment to produce multiple images or pictures of the inside of the body and a computer to join them together in cross-sectional views of the area being studied. The images can then be examined on a computer monitor or printed.

CT scans of internal organs, bone, soft tissue and blood vessels provide greater clarity than conventional x-ray exams.


An x-ray (radiograph) is a painless medical test that helps physicians diagnose and treat medical conditions. Radiography involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging. Used to be imposed onto photographic film, now most X-rays are imposed on a digitizer and stored / viewed electronically.

A bone x-ray makes images of any bone in the body, including the hand, wrist, arm, foot, ankle, knee, leg or spine.

Answer 2

I need to correct Drew M, who said "a mri scan is when you have your whole body scanned cat scan just scans the head"

This is incorrect. Both MRIs and CTs are done of the parts in question. For example, you can have an abdominal CT, or a brain MRI, etc.

Answer 3

An MRI uses powerful magnets to image the body using the hydrogen nuclei in water. You are mostly water, so this is good for imaging soft tissues. Gadolinium is the contrast medium used for this type of scan, and does not involve exposure to radiation.
A CT or computed tomography scan is a series of x-rays taken for very brief intervals using a computer to recreate 3-dimensional images. Uses a contrast medium to enhance images of soft tissue by increasing the contrast between bone and soft structures with compounds based on barium or iodine. This does involve radiation exposure.
An x-ray is eposure to the ionizing radiation from electrons beamed from a source, in a vacuum onto a metal plate. Your bones show up well in x-rays due to their density and the Calcium molecules which make up their crystalline matrix. Barium sulfate is used as a contrast medium for x-rays. X-rays are not good for visualizing soft tissue damage.

Answer 4

a mri scan is when you have your whole body scanned
cat scan just scans the head and a x-ray take negative photos of your bones

Answer 5

MRI (magnetic resonance imaging), uses high speed A.C resonating magnetic pulses with a receiver at the point of inspection,

Answer 6

A cat scan can see all on your inner organs....i had one done on my spleen; you drink stuff to make your insides glow and they take about 1000 pictures; it found that my inner abdomen was bruised....and xray takes pictures of bones