Understanding Differences Between MRI And MRA

If you need to go through some sort of diagnostic imaging to help your physician identify a disorder or illness, then there are a variety of tests that your doctor can order. MRIs and MRAs are both common, and while both of these types of imaging scans seem as though they might be the same thing, they are not. Keep reading to learn about some of the differences between an MRI and an MRA.


An MRA is a magnetic resonance angiography test that allows for a clear image of the body. Like a traditional MRI, the testing is completed to create clear images of the tissues in the body. This is completed in cross-sectional views so abnormalities can be noted. 

While the typically MRI can be quite good at showing tumors, degraded tissues, and damage to joints and organs, they are not particularly good at showing damage to blood vessels. This is where the MRA comes in. During this type of imaging, a contrast dye is injected into the body. This dye flows through the blood vessels and it then shows up on the imaging test as a white areas of the scan. 

The dye is tracked to see where dye cannot reach or where the contract medium can only move through a blood vessel partially. This is how blockages can be seen. This is especially important when it comes to tracing arteries that feed into or away from the heart. It is also used to locate bleeds in stroke victims.


Since the MRA requires an extra step with the injection of the contrast dye, you can expect the procedure to take a bit longer. In general, an MRI can take up to one hour, especially if the entire body is scanned. Very little preparation is needed before the test takes place. With the MRA, it can take up to two hours. This means that an additional hour is required to allow the dye to move through the body. 

You can expect the dye to be introduced into the body using an IV. The dye is typically a gadolinium variety that is removed naturally from the body within about 24 hours. 

You should know that there are very few side effects associated with the dye, but you may experience a headache or other mild issues. Allergies and more serious reactions are extremely rare.

If you want to know more about MRIs, MRAs, and the possible imaging tests that you need, speak with your physician.