MRI-Guided Breast Biopsy

What is it?

For this procedure, magnetic resonance imaging (MRI) is used to guide the radiologist’s instrument to the site of abnormal growth. Once suspicious area is identified, an instrument moves the biopsy needle in position and removes the tissue. Because this type of biopsy uses a needle, damage to nearby tissue is minimal.

What is it for?

An MRI-guided breast biopsy is used when an MRI scan indicates an unusual mass, growth, distorted area or an area with abnormal tissue.

How to prepare

  • You will be given special instructions on what to eat and drink prior to the exam
  • Talk to your health care provider about your medical history, current medical condition, medicines you are taking and any allergies you have
  • You will be asked if you have any implanted medical devices. Implanted medical devices can malfunction or cause problems during an MRI.


  • An allergic reaction may occur from the use of a contrast material (dye)
  • The strong magnetic fields can cause pacemakers and other implants to malfunction
  • Metal inside your body may be moved or shifted slightly because of the magnetic fields
  • An MRI is not recommended if you are pregnant, as it can cause a harmful increase in the temperature of the amniotic fluid
  • There is a risk of bleeding and infection at the biopsy site

What happens during?

  • The procedure usually takes 45 minutes and is done on an outpatient basis. You will be awake during the biopsy.
  • You will lie face down on a moveable examination table
  • An I.V. line is made into your hand or arm for the contrast material. Contrast material assists in seeing precise images
  • Your breast is gently pressed between two compression plates. Using computers, the radiologist determines the exact position of the needle placement
  • It’s important to remain still during the procedure
  • An anesthetic is injected into the breast for numbing
  • A small incision is made in the skin where the biopsy needle will be placed
  • The needle is inserted and moved to the area of the abnormality and imaging is used to validate the position
  • Tissue samples are removed
  • The needle is removed, pressure is applied to stop the bleeding and the skin is covered with a dressing

What happens after?

  • You should avoid strenuous activity for 24 hours following the procedure. After that, you should be able to go back to your normal activities.
  • The removed tissue will be examined and a diagnosis will be made. Sometimes the results will be given to you at the facility and other times the results might be given to your referring physician who will share the results with you at a later time.

Side effects

Contact your doctor if you have bleeding, drainage, redness, swelling or warmth in the breast after going home.

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