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November 13, 2024

What Does an MRI Show, and How Does It Work?

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What Does an MRI Show, and How Does It Work?

Key takeaways:

  • MRI is a medical imaging modality that creates detailed images of soft tissues.
  • An MRI scan shows the distribution of protons within the water in your body, situated in the scanner’s field of view.
  • MRI scanning enables the anatomical and functional characterization of your organs
  • MRI does not use ionizing radiation.

Magnetic Resonance Imaging (MRI)

MRI is a conventional medical imaging modality that uses a combination of magnetic fields and radio waves. It creates exact images of the soft tissues in your body.

MRI enables you to see inside your body without using ionizing radiation. Unlike computed tomography (CT) exams, MRI does not use ionizing radiation.

You would think that what you see on MRI scans is like photography of the organ, but it is not. MRI actually images the protons within the water in your tissue

How Does an MRI Work?

The strong magnetic field will temporarily align all the protons of the part of your body in the same direction, as a compass would point north.

When a radio wave interference is introduced and then stopped, the protons get back to their original position and faint radio waves. This signal is picked up and transformed by a computer to create detailed internal images of your body.

On the MRI scan, you can clearly see the inside of your body and any related abnormalities. The computer generates an image that a  radiologist can interpret

What Does an MRI Show?

Radiologists use different MRI sequences depending on what they are looking for. Sequences called T1, T2, and DWI are the most commonly employed.

What Does an MRI Show in T1-Weighted Scans?

On a T1-weighted MRI scan, fat appears bright, and water appears dark. In other words, bright spots on the pictures could be slowly flowing blood, protein-rich fluid, or fatty acids.

In contrast, dark spots could be edema, tumor, infarction, inflammation, infection, hemorrhage, calcification, or a void of flow.

What Does an MRI Show in T2-Weighted Scans?

On a T2-weighted image, fat and water will both appear bright. This is the most basic sequence used in MRI. In this setting, an edema, tumor, infarction, inflammation, and infection will be displayed as dark regions while flow void, fibrosis, calcification, and protein-rich fluid appear bright.

What Does an MRI Show in DWI Scans?

On a diffusion-weighted image (DWI), tissue with a high density in cells and swollen cells appear dark because of their low diffusion coefficient.

DWI is a series of T2-weighted sequences to image the motion of water in molecules. The DWI sequences can help detect tumors and brain ischemia.

Indeed, an expert radiologist interprets the scans and helps you understand what you see.

Different Types of MRI Machines

MRI machines come in different models. The two main models are closed and open depending on their shapes.

1. Closed MRI

Such an MRI scanner is shaped like a short or long tube and a sliding bed in the middle. Closed MRI is commonly used to get high-resolution images. Usually, the closer the detectors are to your body, the more radio waves will be received. Therefore, the images will be more detailed.

2. Open MRI

This type of machine has a clearly different shape than the closed MRI described above. An open MRI scanner is designed for people with claustrophobia. The open setting decreases anxiety as patients are not in an enclosed space.

At ezra, your comfort and well-being is our priority. Our MRI machines use 70cm (wider) bores for your full-body scan.

MRI Scan Indications

What does an MRI show: MRI scan indications

Your doctor will prescribe an MRI exam to “see” the cause of symptoms. At ezra, we believe it’s important to not wait for symptoms to appear.

If you’ve ever wondered, “What does an MRI show at ezra?”, our full-body MRI can screen 13 organs (brain, spine, thyroid, liver, gallbladder, pancreas, spleen, kidney, adrenal glands, bladder, ovaries, uterus, and prostate).

What Are the Contraindications of an MRI Exam?

Overall, an MRI exam is safe and non-invasive. However, because MRI uses powerful magnets, you can’t undergo an MRI exam if you carry any metallic or electronic items that are not MRI-compatible, such as:

  • Pacemaker
  • Aneurysm clips
  • Artificial heart valves
  • Artificial joints
  • Body piercing that can’t be removed
  • Cochlear implant
  • Dental work, including metal
  • Metal implants
  • Metal fragments in your body like shrapnel
  • Tattoos made with metallic ink

Ready for Your MRI Exam? Here Is What To Expect

Woman with short dyed blond hair looking at camera

At ezra, our technologists will ask you to remove any metallic or electronic objects before entering the MRI machine room. The magnets of the MRI are powerful. We want you to stay safe when around the equipment.

These metallic or electronic objects can be:

  • Smartphones
  • Glasses
  • Earrings, bracelets, and necklace (Pieces of jewelry in general)
  • Belt, wired bras
  • Hairpins

Before the MRI Scan

Before the start of the scan, you will need to change into our comfortable ezra pajamas.

Then as you enter the MRI room, the technologist will ask you to lay down on your back on the sliding bed.

Learn more on what to expect before your ezra screening.

During the MRI Scan

As soon as the scan starts, you will notice the noise coming from the magnet. So, for your comfort, ezra will provide earplugs with your favorite Spotify playlist.

Learn more on what to expect during your ezra screening.

After the MRI Scan

After the scan, the technologist will help you out of the sliding bed. You will exit the MRI scanner room and dress.

You will receive the MRI scan results within 5 business days. Your ezra medical provider will guide you through the results. At your request, we can also share the results with your primary care physician.

What Are the Limits of MRI?

An MRI exam has limitations that you should be aware of:

  • Distortion of the image, also called artifact, occurs if the patient moves during the scan. Breathing and bowel motion also create artifacts.
  • Cancerous tissue can be difficult to discriminate from edema, as inflammation also occurs near tumors. MRI is not recommended for pregnant women until at least the third trimester.
  • If using contrast dye to explore medical conditions related to blood vessels, there could be a risk of an allergic reaction to the contrast material. (Note: Ezra does not use contrast dye for the ezra full-body MRI.)
  • Ask your doctor about your kidney function if your screening will involve contrast dye. The contrast agent gadolinium has been related to renal issues. Note that ezra does not use any contrast material.

What Does an MRI Show at ezra?

Our full-body MRI scan will provide information about 13 organs. Our clinician will also talk you through actionable and easy-to-interpret findings.

If you’d like to know more about your risk of developing cancer, take our five-minute questionnaire. You can then decide if a full-body MRI scan at ezra is the right fit for you.