A magnetic resonance imaging (MRI) scan is a non-invasive diagnostic procedure commonly used around the world.
An MRI scan can be performed on the brain, breast, bones, heart, and other parts of the body to determine any anomalies that are related to a diseaseBut how do you read an MRI scan?
Verify the image and patient information first
Before you can start reading an MRI scan, you need to verify if the images are from the correct patient first. Technicians will label images with the name of the patient and the time and date of the scan, which will help you locate the most up-to-date images if you’re looking at a series of scans.
It would also be helpful to look for previous scans if there are any. You should also verify if you’re looking at the correct body part or the correct side if you’re dealing with the upper or lower limbs.
Check for the T2 and T1 images
There are basically two major types of MRI images: T2 and T1 weighted images. These images both represent different tissues based on the timing of the RF pulses. T1 means one bright tissue that’s mostly composed of fat while T2 means two bright tissues composed of fat and water.
Between these two images, T2 is more commonly used while T1 is utilized for analyzing anatomical structures or to compare between fat and water bright signals.
When reading the MRI, check the T2 weighted images first for any abnormal signals across different planes. Carefully work through the anatomy of the area that you want to examine to make sure that all planes are covered.
If you find any abnormal signals, take note of their size, location, intensity and shape, and compare both sides of the image if available.
You can use T1 or fat-sensitive images as a comparison against your T2 or water-sensitive images. This will allow you to determine some anomalies like the presence of inflammation or ischemia. Aside from these images, you can also look into different MRI sequences including:
- Short tau inversion recovery (STIR). This sequence is based on a T2 weighted image that’s manipulated in a way that nullifies fat and other materials with the same signals.
- Fluid attenuated inversion recovery (FLAIR). This is similar to T2 weighted images but it nullifies the cerebrospinal fluid (CSF) signal, making it useful for evaluating parts of the central nervous system.
Look out for abnormal MRI signals
As you look at the different images from various MRI sequences and modalities, it’s very important to check for abnormalities in the MRI signal.
Be on the lookout out for the nature of signal change and the size, shape, and anatomical location of the abnormality. It also helps to compare different scans to determine how much fat and water are present within that body part.
Correlate the images
To get a better picture of your scan, you can correlate the MRI images to any previous imaging or other modalities. For instance, you can compare X-ray images with those you’ve seen on the MRI to confirm the presence of an abnormality.
You should also look into the condition in question and look into the correlation of the physical signs and symptoms to the diagnostic results from the MRI and other procedures. This will help you come up with a good diagnosis and plan treatments according to what a patient needs.
Remember that while the MRI scan will reveal the exact position and size of an abnormality, you will still need the clinical history of the patient to really determine the right diagnosis for his condition.
Of course, don’t forget to always compare both sides of a scan and be methodical with your analysis to come up with the best results.
An MRI scan is definitely one of the best tools out there for diagnosing different medical conditions, especially when used in correlation with other medical procedures.