In a MRI-guided breast core biopsy, MRI technology is used to guide the biopsy instrument to the abnormality in your breast. Once the instrument is in the right place, the radiologist performs the biopsy while you are outside the magnet but still on the MRI table in the same position. Breast MRI does not use ionizing radiation (used in X-rays).
This procedure is used when abnormalities cannot be sampled by other simpler imaging methods, such as stereotactic core biopsy or ultrasound guided biopsy. Stanford employs a state of the art MRI-compatible custom biopsy table, equipment and grid system to make this technique as easy as possible for our patients
For this procedure, patients lie flat on their stomach on the MRI biopsy table. With the breast placed in a special platform, the MRI machine is used to locate the mass to be biopsied. After local anesthetic is applied to minimize pain a small incision (about 1/4 inches long or 6 millimeters) is made, through which a hollow biopsy needle is inserted into the breast to remove core samples of the mass detected in the MRI. The radiologist guides the needle to the suspicious area and takes several samples of this breast tissue. These samples will be sent to the pathologist who performs microscope analysis and makes a diagnosis. This procedure takes about 45 minutes on the table for each area of concern sampled.
In some cases, a small permanent metal marker measuring 1/8 inches (2 mm or less) is placed at the site of the abnormality to help guide a surgeon in case surgery is needed at a later time. The marker is made of safe metal used in other implantable devices and will not set off metal detectors.
After the biopsy, pressure is applied to the incision site to control the small amount of bleeding that may occur. After bandages are applied, the radiologist will explain after-procedure care and follow-up to the patient.