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Breast MRI
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Introduction
Magnetic resonance breast imaging (MRI, MR) has been approved by the U.S. Food and Drug Administration (FDA) since 1991
for use as a supplemental tool, in addition to mammography, to help diagnose breast cancer. Breast MRI is an excellent problem
solving technology. It is often used to investigate breast concerns first detected with mammography, physical exam, or other
imaging exams.
MRI is also excellent at imaging the augmented breast, including both the breast implant itself and the breast tissue surrounding
the implant (abnormalities or signs of breast cancer can sometimes be obscured by the implant on a mammogram). MRI is also
useful for staging breast cancer, determining the most appropriate treatment, and for the patient follow-up after breast cancer
treatment.
Not A Screening Exam
Breast MRI is not a “screening” exam. Mammography remains the screening method of choice, and is recommended as such by
the American Cancer Society, American Medical Association, and other medical specialty organizations. While mammography is
effective in about 85% of cases, it is not perfect, and in approximately 15% of cases additional information is needed in order to
form a diagnosis. In these cases, a breast ultrasound might be ordered, or a breast MRI.
Breast MRI: Clinical Indications for Exam
Magnetic Resonance Imaging, MRI, of the breast has proven to be an extremely valuable adjunct to physical examination, mammography,
and ultrasound techniques in the evaluation of breast disease. The sensitivity (the capacity to find abnormalities) for detection of invasive
breast cancers as small as 3mm is reported to be greater than 95%, and in combination with other imaging methods, most but not all
invasive cancers, may be detected at the earliest possible stage.
The indications for breast MRI continue to expand, and include the areas of detection, staging, neo-adjunct therapy monitoring and localization
for surgical procedures. Specific indications include the following:
Breast Augmentation – unequivocally, the most accurate study for implant
complications
Indeterminate Mammogram – differentiation of benign from potentially malignant
lesions
Dense Breasts – mammograms and ultrasound may not detect lesions in these
patients
High Risk Patients – breast cancer gene carriers and history of lymphoma and
Hodgkins disease
Pregnant Patients – MRI is acceptable and effective with no ionizing radiation
Preoperative Staging – extent of disease and determination if other cancers are
present in either breast
Postoperative Evaluation – MRI can reliably differentiate post –surgical scar
from recurrent cancer
Neo-adjunct Chemotherapy – monitor response and place metallic tumor markers
for future reference
Occult Breast Cancer – patients with abnormal lymph nodes or tumor markers with
negative studies
Close or Positive Surgical Margins – MRI may locate residual or additional
tumor foci
Undetected Multiple or Bilateral Cancers – additional malignancies have been
detected in several patients not seen on other imaging modalities in our
experience at Inland Imaging
Limitations of Breast MRI
MRI has significant promise as a supplemental tool to mammography in the diagnosis of breast cancer. However, MRI still has additional hurdles
to undergo in order to gain wide spread acceptance and use. First, MRI cannot always distinguish between cancerous and non-cancerous abnormalities.,
which can lead to unnecessary breast biopsies.
Another drawback of breast MRI is that it is unable to image calcifications; tiny calcium deposits that can indicate breast cancer. Mammography, on the
other hand, can reliably image calcifications, which are often associated with early-stage breast cancers such as ductal carcinoma in situ (DCIS). Also,
MRI has been shown to produce a moderate amount of false-positive results. In other words, the results of an MRI sometimes show that a suspicious
abnormality is present in the breast when in fact, cancer is not present.
MRI is a relatively expensive exam. An average MRI of the breasts costs about $1,200 versus about $100 for a screening mammogram.
The Exam
Unlike mammography which uses low dose x-rays to image the breast, MRI uses powerful magnetic fields and radio waves to create images of the breast.
MRI is able to achieve views in any plane and from any orientation while x-ray mammography requires re-orientation of the breast and mammography
system for each view desired. The typical breast MRI exam takes 30 to 40 minutes following the injection of a non-ionic contrast material called Gadolinium
which is injected into a vein in the arm before or during the exam, and which helps improve the quality of the images. This contrast agent helps produce
stronger and clearer images and ‘highlight’ any abnormalities.
Patients undergoing a breast MRI exam lie face down on the MRI imaging table which is specially configured so that the breasts are positioned to hang freely
through two openings called breast coils. These so called coils, are the devices through which image acquisition is obtained.
CADSTREAM
Every Breast MRI performed at Inland Imaging is read by a radiologist. In addition, Inland Imaging processes every breast MRI on a special computer
workstation and software called CadStream. This software acts as a second set of eyes, scanning minute detail in the images for potential abnormalities, and
flagging any that it finds. This computer aided detection is very helpful to radiologists in assisting with the diagnosis.
Scheduling An Exam
You should discuss with your personal doctor whether you should schedule a Breast MRI exam. Insurance coverage is dependent upon medical necessity,
and meeting your plan guidelines. If after consultation with your physician you decide to schedule a Breast MRI, and have obtained a referral, you may schedule
your exam at any of the following three Inland Imaging locations:
At a center convenient to you:
Inland Imaging at Sacred Heart Doctors Building
Inland Imaging at Holy Family
Inland Imaging Valley Center
For insurance information contact: Denise Stone, 363-7748
To schedule a Breast MRI or obtain additional information: Paula Taylor, 363-7633
You may fax Paula at 363-7095
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| Tuesday, September 07, 2010 |
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© 2005 Inland Imaging
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