Difference between MRI and Ultrasound
By Theydiffer - September 28, 2015

MRI, or magnetic resonance imaging, is the technique that uses a magnetic field to provide the images of the insides of the human organism. MRI is recognized as the most efficient technique in modern medicine when it comes to researching the pathologies of soft tissues in the human organism. Ultrasound is the technique that utilizes sound waves. The ultrasound machine sends sound waves and  the sound waves that come back are monitored. There are several differences between MRI and ultrasound techniques and equipment, and we will take a closer look at those.


MRI, or magnetic resonance imaging, is able to align molecules in the human organism with the help of magnetic fields. Thus, the machine is able to scan the rate of change of the molecules’ orientation. This analysis provides the MRI machine with the basis for creating relevant images of what is going inside the human body.

An ultrasound machine works via utilizing  sound waves. The principle of operation of ultrasound apparatus is relatively simple. The machine emits sound waves into the desired part of the body and checks those sound waves that are returned. Based on this data, ultrasound apparatus is able to create an image of the relevant process inside the human organism.

Comparison chart

MRI machines are massive and they cost a lotSmall and relatively cheap
Provides a static imageCreates a real time visualization
Is able to look through a boneIs not able to look through a bone

MRI vs Ultrasound

What is the difference between MRI and ultrasound? Let’s compare them by the size of the equipment, the type of resulting images and the ability to look deep into the human organism.

  • The machines that provide MRI scans are massive. Besides, they cost much more than tiny ultrasound gadgets.
  • Due to the specifics of the technological process, the images resulted in an MRI scan are static. With the series of static images the MRI apparatus creates a three-dimensional image of the process it is focused on. The output image of the ultrasound apparatus is completely different. Ultrasound allows for a real time motion image of the object the medical specialist is examining.
  • The MRI scanning machine is very powerful and can actually see through the bone of the human body. Ultrasound technique is less powerful than MRI, and is not able to see through human bones. Therefore, a scanning procedure that requires examination of the bones may be impossible with ultrasound.