Difference between CT scan, MRI and PET scan

All these three are types of scans that are used for diagnosis of different diseases. MRI, CT scan and PET scan are all indicative apparatuses to non-intrusively impression inside the body. They are altogether in light of the way that specific things occur to atoms in bodies when they ingest energy. Resonance alludes to the level of assimilation accomplished by regulating the frequency of radiation.

CT scan

A CT scan (computed tomography) makes utilization of computer prepared combinations of numerous X-rays pictures taken from various points to create cross-sectional pictures of particular ranges of a filtered object, permitting the client to see inside the body without cutting. It is frequently alluded to as CAT scan that is abbreviation of computer aided tomography. CT scan is usually done when we want to scan our head for internal injury.


MRI which is abbreviation of “magnetic resonance imaging” is a restorative imaging strategy utilized as a part of radiology to frame images of the life structures and the physiological procedures of the body. MRI scanners utilize powerful magnetic fields to produce pictures of within the body.

PET scan

PET is abbreviation of “Positron emission tomography”. It is an atomic pharmaceutical, utilitarian imaging system that is utilized to watch metabolic procedures in the body. The framework recognizes sets of gamma beams discharged in a roundabout way by a positron-emitting radionuclide, which is brought into the body on a naturally dynamic particle.

CT scan VS MRI VS PET Scan

In article we are going to give you a clear understanding about these terms by discussing the difference between them.

  • Purpose:

The main purpose of CT scan is to have a more intensive look at the delicate tissues, organs, blood vessels and infection in your body.

MRIs are normally utilized for purpose to analyze any irregularities all through the body, for example, tumors and mind aneurysms.

The main purpose of PET scan is to figure out normal brain and function of heart and it is valuable in cancer research.

  • Time:

A CT scan almost take 5 minutes to take a picture, as it requires less time to take images.

MRIs can take about thirty minutes by and large as speedy will be done in 15 minutes whereas long can go to 2 hours, to take a picture.

There is an hour long resting period before PET scan, and your genuine scan will requires around 15-35 minutes.

  • Radiation:

CT scan includes radiation, which is more often than not in the surrounding area of 2 and 10 mSv.

X-rays don’t include any ionizing radiation at all, which is the motivation behind why they are a superior decision in such a variety of circumstances.

PET scan also includes some radiation which is of 370 to 555 megabequerels.

  • Limitations:

You will most likely be unable to fit into a traditional CT scanner in case you’re heavier than 450 lbs.

You can’t get MRIs in the event that you have metal embeds in your body.

In PET scan, radiation is biggest risk so pregnant women can’t go for this scan. This scan is also very expensive which is not acceptable for everyone.


From the above article we can conclude that MRI is far better than CT scan and PET scan because of no radiations but CT scan and PET scan are good for tumors and cancers. CT scan is very important in identification of cancer or any other fatal disease. As the radiations in MRI are very less as compared to CT scan and PET consequently the side effects are also less.