What is the difference between an MRI and a CT scan?

Both MRI and CT scans make cross-sectional images (slices) of almost any area of the body using a sophisticated computer system. The major difference is that an MRI uses a large magnet and radio waves to produce images while a CT scanner uses x-rays. Therefore, with the MRI studies, there is no exposure to x-rays. Both systems complement each other well as they both have their inherent strengths and weaknesses; however, CT usually can only directly acquire transverse (or crosswise) images, whereas MRI can directly acquire slices in any plane. In addition, MRI is superior when it comes to soft tissue contrast, and there are no known side effects. The ability to view pictures from multiple directions, high tissue contrast, and absence of x-rays make MRI a very powerful and increasingly popular imaging tool.

The main difference in how CT and MRI scanners acquire images is in the form of radiation that is employed. CT uses ionizing radiation in the form of x-rays. The x-rays re directed through the body as a thin beam and then into a detector and are reconstructed into an image with a computer. A CT scanner will only acquire images in one plane. These images can then be manipulated via computer after the scan to obtain more information. MRI scanners use non-ionizing radiation in the form of radio waves (in approx. the fm radio range). These radio waves are directed at the body in the presence of a strong magnetic field. These interact with the plentiful hydrogen protons found in our tissues. The result of this interaction is a signal that is detected by the scanner and then reconstructed by a computer. These radio waves and magnetic fields can be manipulated and varied to obtain many different planes and many different types of images.  more

Both MRI and CT scans provide detailed pictures of areas of the body that used to be inaccessible by conventional x-rays. They use a sophisticated computer system to make cross-sectional pictures of areas of the body being scanned. The major difference between CT and MRI, is that an MRI uses a large magnet and radio waves to produce images, whereas a CT scanner uses x-rays. There is, therefore, no exposure to x-rays in an MRI scan. Because MRI scanning is very sensitive to movement during the scanning procedure, CT scanning can be preferable in some circumstances if the patient is unable to stay still.  more

Both MRI and CT scans make cross-sectional images (slices) of pretty much any area of the body using a sophisticated computer system. The major difference is that an MRI uses a large magnet and radio waves to produce images while a CT scanner uses x-rays. Therefore, with the MRI studies, there is no exposure to x-rays. Both systems complement each other well as they both have their inherent strengths and weaknesses; however, CT usually can only directly acquire transverse (or crosswise) images, whereas MRI can directly acquire slices in any plane. In addition, MRI is superior when it comes to soft tissue contrast, and there are no known side effects. The ability to view pictures from multiple directions, high tissue contrast, and lack of x-rays make MRI a very powerful and increasingly popular imaging tool. Please note, MRI is very sensitive to motion during the acquisition of pictures and, in some instances, CT is preferable if the patient is unable to stay still. Watch a Video.  more

Both MRI and CT scans make cross-sectional images (slices) of pretty much any area of the body using a sophisticated computer system. The major difference is that an MRI uses a large magnet and radio waves to produce images while a CT scanner uses x-rays. Therefore, with MRI examinations there is no exposure to x-rays. Both systems complement each other well as they both have their inherent strengths and weaknesses; however, CT usually can only directly acquire transverse (or crosswise) images, whereas MRI can directly acquire slices in any plane. In addition, MRI is superior when it comes to soft tissue contrast, and there are no known side effects. The ability to view pictures from multiple directions, high tissue contrast, and lack of x-rays make MRI a very powerful and increasingly popular imaging tool. Please note, MRI is very sensitive to motion during the acquisition of pictures and, in some instances, CT is preferable if the patient is unable to keep still.  more

A CT scan uses ionizing radiation to obtain the information whereas MRI uses the magnet and Radiofrequency waves. For most types of organs and diseases MRI is preferred because it provides superior images with better definition than CT scanning.

Both MRI and CT scans make cross-sectional images (slices) of pretty much any area of the body using a sophisticated computer system. The major difference is that an MRI uses a large magnet and radio waves to produce images while a CT scanner uses x-rays. Therefore, with the MRI studies, there is no exposure to x-rays. Both systems complement each other well as they both have their inherent strengths and weaknesses; however, CT usually can only directly acquire transverse (or crosswise) images, whereas MRI can directly acquire slices in any plane. In addition, MRI is superior when it comes to soft tissue contrast, and there are no known side effects. The ability to view pictures from multiple directions, high tissue contrast, and lack of x-rays make MRI a very powerful and increasingly popular imaging tool. Please note, MRI is very sensitive to motion during the acquisition of pictures and, in some instances, CT is preferable if the patient is unable to hold still.  more

I'm not an expert-- my understanding is that a CT scan uses X-rays to generate a 3-model of the internals. The MRI uses really really powerful magnets to vibrate the water molecules to model the insides.  more

A CT scan is a specialized type of X-ray. The results are translated into images that look like a "slice" of the body part. Contrast, which is iodine-based is sometimes used. CT scans are also good for imaging bone. The major difference is that an MRI uses a large magnet and radio waves to produce images while a CT scanner uses X-rays. Therefore, with the MRI studies, there is no exposure to X-rays. Contrast agents are also used in MRI however they do NOT contain iodine agents. MRI is superior when it comes to soft tissue contrast, and there are no known side effects.  more

Both MRI and CT scans make cross-sectional images (slices) of areas of the body using a sophisticated computer system. The major difference is that an MRI uses a large magnet and radio waves to produce images, whereas a CT scanner uses x-rays. There is, therefore, no exposure to x-rays in an MRI scan. MRI scanning is very sensitive to motion during the scanning procedure, in some instances, CT scanning is therefore preferable if the patient is unable to stay still.  more