What is a MRI Guided Breast Biopsy?
A MRI-guided breast biopsy is used to take tiny samples of your breast tissue that can be studied under a microscope. During this procedure, an MRI machine is used to locate the tissue to be removed. This biopsy may prevent the need for an open (surgical) biopsy.
The total appointment, including pre- and post-biopsy counseling and paperwork, as well as a post non-compression mammogram, will take about two hours. The MRI-guided breast biopsy does involve mild breast compression, which makes it similar to a mammogram. It also requires the injection of a contrast material through a vein in the arm and will necessitate an IV be started. MRI-guided biopsy is a safe procedure, however it does have some rare risks. These include bleeding, infection and failure to remove the right tissue from the biopsy site as well as mild side effects or reaction to the contrast material.
When having an MRI-guided biopsy, you will be asked to undress from the waist up and remove any other clothing that contains metal such as snaps or zippers as well as jewelry and hair clips or pins. An IV will be started in your arm in order to inject contrast at the appropriate time. While lying on your stomach, your breast will be guided into an opening in the coil used to image it and mild compression with a special grid will be applied. You will be moved inside the MRI scanner and a number of scans will be performed including the injection of the contrast material through the IV in your arm. You will be brought back out of the scanner and the radiologist will calculate the location of the area to be biopsied based on these images. Areas of skin on your breast will be cleansed with alcohol through the grid compressing it. The area will then be numbed with a local anesthetic so you will not feel pain. This may sting slightly initially. A small incision is made into the skin surface and a plastic guide is inserted into your breast at the exact location and depth the radiologist calculated based on the scans just completed. You will be moved back into the MR scanner and another scan will be done to verify that the guide is in the correct location and depth. Once that is done, the table will be brought back out of the scanner and the radiologist will insert the special biopsy needle into your breast using the guide for placement. The needle is used to remove small samples of breast tissue. A tiny clip is then inserted into the site where the tissue was removed. This is to mark the area of the biopsy internally and also serves as a marker for future reference. You will, once again, be moved back into the scanner for one more scan. After that scan, the table will be moved back out of the scanner. The guide will be taken out of your breast, the grid compression removed and mild pressure will be applied to your breast until the bleeding stops. An antiseptic ointment is applied to the skin, it will be bandaged and the IV removed from your arm. A non-compression mammogram will be done to verify the location of the marker clip that was inserted. You will then be able to get dressed and go home soon after.