Breast MRI is a sophisticated technology that uses a computer, magnetic field and radio waves instead of x-rays to produce images of the soft tissues in the body. This non-invasive procedure helps better evaluate the breast in special circumstances. When used in conjunction with screening and diagnostic mammography, it can provide valuable information for the detection and characterization of breast disease.
If MRI is used, it should be in addition to, not instead of, a screening mammogram. While an MRI is more likely to detect cancer than a mammogram, it may still miss some cancers that a mammogram would detect. MRI also has a higher false positive rate (where the test finds things that turn out to not be cancer), which would result in unneeded biopsies and other tests if performed on a large portion of women.
An MR-guided biopsy is the latest development and an important advance in diagnosing breast cancer. It is most useful when an ultrasound or stereotactic-guided biopsy is not appropriate because the area of concern is not well seen by mammogram or ultrasound, but is discovered or is most conspicuous on MRI.
What Should I Expect?
During an MR-guided biopsy, a local anesthetic is injected into the breast to numb it and contrast material is given intravenously. You will be positioned face down on your stomach and your breast(s) will be positioned into a cushioned opening containing a special breast-imaging coil. Using computer software, the radiologist determines the position and depth of the lesion for biopsy. When the tissue sampling is complete, a small marking clip may be left at the site of biopsy, so it can be easily located for future follow up if surgery becomes necessary.
You will be asked to remove all jewelry, since these items disturb MRI signals. It is very important that any prior breast films (mammograms, ultrasound or MRI) be available to the radiologist for comparison. If you have had these at a facility other than Iowa Clinic Medical Imaging, please let us know so we may obtain the films for comparison or bring them with you on the day of your appointment.
Many of these items are contraindications to having an MRI as they are not compatible with the magnetic field present around all MRI machines. If you have any of the items listed below, call 515.875.9740 so we can make arrangements for you before your appointment.
- Cardiac Pacemaker
- Artificial heart valve prostheses
- Aneurysm clips
- Eye implants or metal ear implants or any metal implants activated electronically, magnetically or mechanically
- Copper 7 IUD
- Shrapnel or non-removed bullet
- Weight over 350 lbs
- Any metal puncture(s) or fragment(s) in eye