What Is an MRI?

MRI stands for magnetic resonance imaging. It is an imaging technology that creates 3-D images of the body’s internal anatomy using strong magnetic fields and radio waves, not X-rays.

An MRI allows your healthcare team to view the structures of the brain, if a tumor is present, and details about the tumor that can help in determining the best course of treatment.

Medulloblastoma will show up on an MRI as a solid mass in the back of the brain.

After diagnosis of a medulloblastoma tumor, it is normal for a patient to also have a full MRI of the spinal cord. This will help your care team determine if the cancer has spread.

What Is It Like to Have an MRI?

Having an MRI involves lying down in an MRI scanner, which is a large machine usually in the shape of a tube. You have to lie still while the pictures are taken. Getting an MRI does not hurt. The scanner can make a loud banging sound during the procedure. Young children are often given anesthesia to have an MRI, as it is hard for them to lie still for the length of time needed to complete the scan.

An MRI can take anywhere from 20-90 minutes to complete.

What Does MRI “with Contrast” Mean?

Sometimes an MRI will be done with something called a “contrast medium.” This is a special dye that’s given to the patient before the MRI. The contrast helps create a clearer picture. It is a safe drug that is usually given by intravenous (IV) injection in the patient’s hand or arm.

The Use of CT Scans in Medulloblastoma

CT stands for computed tomography. This is an imaging technique that takes pictures of the inside of the body using X-rays from different angles. CT scans can help in measuring the size of the tumor. A contrast medium, explained above, is sometimes also used during a CT scan.

CT scans are a good option when a patient is unable to undergo an MRI.

While CT scans are sometimes used when diagnosing medulloblastoma, MRI is the preferred imaging tool because it doesn’t use radiation, and for its ability to provide detailed, clear images of the soft tissues that form the brain.