Breast Mass Protocol
Overview
Currently
breast MRI has five primary purposes; evaluation for breast implant rupture, as
diagnostic tool in the evaluation of known or suspected breast cancer, imaging
of the axillary region in cases of axillary lymphadenopathy with unknown
primary, monitoring response to post-surgical primary chemotherapy, and
pre-surgical evaluation of residual disease following neo-adjuvant
chemotherapy.
The
following protocol is designed for evaluation
of patients with known or suspected breast cancer and not for breast implant
rupture.
Gadolinium
(Gd) enhanced imaging is the mainstay of breast MRI in evaluation of a known or
suspected breast tumor, extent of disease in patients with known breast
malignancy, and recurrence of tumor after treatment. Post-contrast high
spatial resolution images are ideal for evaluating lesion morphology.
Post-contrast high temporal resolution images generally have lower spatial
resolution but allow analysis of enhancement kinetics in any lesion. The
sequences described below are optimized for a spatial resolution sufficient to
allow lesion morphology analysis and for a temporal resolution sufficient to
evaluate the enhancement kinetics. Currently the highest specificity can
be attained evaluating both lesion morphology and the kinetic enhancement
pattern of the lesion on dynamic 3D spoiled gradient echo (SPGR) with fat
saturation study.
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IMAGING PARAMETERS |
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Plane |
3 plane |
Sagittal |
Axial |
Axial |
Sagittal |
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Mode |
2D |
2D |
2D |
3D |
3D |
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Pulse Sequence |
Localizer |
SE |
IR |
SPGR |
SPGR |
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Imaging Options |
None |
NPW |
Fast,NPw,seq,VBw |
Fast, ZIPx2,MPh |
Fast, ZIPx2 |
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SCAN TIMING |
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# of Echoes |
1 |
1 |
1 |
1 |
1 |
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TE |
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Min Full |
102 |
Minimum |
Minimum |
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TR |
|
500 |
4000 |
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Flip Angle |
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30 |
30 |
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Bandwidth |
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31.25 |
31.25 |
31.25 |
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ADDITIONAL PARAMETERS (see attached
instructions) |
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SAT |
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Fat |
Fat |
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ACQUISITION TIMING |
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Freq |
256 |
256 |
256 |
512 |
512 |
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Phase |
128 |
160 |
160 |
192 |
192 |
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NEX |
1 |
2 |
3 |
1 |
1 |
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Phase FOV |
1 |
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1 |
1 |
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Locs Before Pause |
-- |
-- |
0 |
1 |
1 |
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Freq DIR |
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A/P |
R/L |
A/P |
A/P |
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Water |
Peak |
Peak |
Water |
Water |
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Auto Shim |
Yes |
Yes |
Yes |
Yes |
No |
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Contrast |
No |
No |
No |
Yes |
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Phase Correct |
No |
No |
Yes |
No |
No |
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SCANNING RANGE |
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FOV |
48 |
24 |
34 |
34 |
18 |
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Slice Thickness |
10 |
5 |
5 |
5(2.5) |
5(2.5) |
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Spacing |
20 |
Interleave |
1 |
-- |
-- |
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Start - End |
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Graphic |
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Graphic |
Graphic |
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# Slices |
9/plane |
36 |
18 |
28 |
28 |
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Scan Time |
0:33 |
5:36 |
4:08 |
1:35 per scan |
1:35 |
NPW: No Phase Wrap VBw: Variable Bandwidth
Seq: Sequential MPh: Multi-Phase
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Common Indications ICD9 Codes |
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Abnormal mammogram |
793.8 |
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Palpable mass |
611.72 |
Scheduling Guidelines
¡¤
Approved
Reimbursable Indications
1.
diagnosis is inconclusive, even after standard workup
2.
post-op: when scar tissue cannot be differentiated
from tumors
3.
positive axillary nodes but no known primary
4.
rupture of breast implant
5.
determination of extent of disease in patients with
known malignancy, prior to treatment (to assure confinement to one segment of
the breast)
¡¤
First Ask
1. Why is the breast MRI
being requested? Does the referring physician want one or both breasts
imaged?
2. Do you have breast
implants?
3. Do you have a breast
mass?
4. Have you had breast
cancer?
For patients with breasts implants,
please ask the following:
1.
How long have you
had the implants?
2.
What type of
implants do you have? Silicone, saline or both?
3.
Has there been a
recent change in your implants?
4.
Do you or your
doctor think there has been an implant rupture?
The
breast MRI for evaluation of implant rupture alone does not require Gd
injection. If the patient has a mass not related to the implant then she will
require an injection of Gd.
For
patients with a breast mass, ask the following questions:
1. Have you had a recent mammogram?
2. Did your mammogram have an abnormal finding? Was
the abnormal finding in the area where you feel the mass?
3. Have you had a breast ultrasound?
4. Have you had a biopsy of the breast mass? If the
answer is ¡°yes¡±, what were the results?
5. Do you have a personal or family history of breast
cancer?
6. Is the breast MRI intended to better characterize the
known breast mass, look for other areas of disease in the same breast, in the
contralateral (opposite) breast or all of the above?
For
patients with a history of breast cancer, ask the following questions:
1- When did you have breast cancer?
2- Did you have surgery? When and what type of
surgery did you have?
3- Were your lymph nodes involved with cancer?
4- Have you had chemotherapy or radiation therapy?
If yes, when did you stop your treatments?
5- Is your doctor concerned about recurrent cancer or a new
breast cancer? In the same breast or the opposite breast?
6- Have you had a recent mammogram? Did it show a
change?
7- Can you or your doctor feel a new mass? If yes,
is it in the same area as your previous cancer or in a new area?
8- Do you know if your breast cancer has spread to other
parts of your body?
9- Is the breast MRI intended to better characterize the
new or recurrent finding, look for other areas of disease in the same breast,
in the opposite breast or all of the above?
¡¤
Ask the patient
to bring all available mammograms with her at the time of the MRI examination.
This is extremely important. If mammograms are not available, notify the
radiologist who will be monitoring the exam. Also have all recent
mammogram and ultrasound reports faxed to MRI unit prior to the date of breast
MRI study. All breast masses will be evaluated with Gd.
¡¤
Whenever possible
schedule exam to occur between day five and day fifteen of the menstrual cycle
(day one is the 1st day of menstruation). Otherwise there may be excessive
enhancement of normal breast glandular tissue requiring a callback exam for
reevaluation.
Patient preparation
¡¤
Start intravenous
line (20 or 22 gauge IV). If IV caliber is smaller than 22 gauge,
then it may be useful warming Gd contrast up to body temperature to reduce its
viscosity.
¡¤
Valium (5-10mg
po) or Xanax (1-2 mg po) if patient is claustrophobic.
¡¤
Ear plugs

Coil: Dedicated breast coil is optimal for superior signal
to noise.
Patient Positioning:
Prone, head first. Patient must
have comfortable pillow for head and arms. Be careful that patient is centered
in the coil. There is a tendency for patient to slide too far superiorly in the
coil. To counteract this tendency, ask the patient to slide 2-3 cm toward feet
after she lies prone on the coil.
Landmark: Mark at center of the breast coil
Series
1: 3-Plane
Localizer
This
is a quick localizer sequence obtained in three planes. It is used to confirm
optimal patient positioning within the breast coil. The sagittal views are most
helpful. Bright signal from the inferior aspect of the coil should end at the inframamary fold. This will allow maximum coil signal
superiorly.
Series 2:
Sagittal T1

¡¤
Prescribe
graphically on an axial slice that is centered between the axilla
and inframammary fold, not the center of the breast.
This will allow better visualization of the axillary nodes.
¡¤
Scan direction
should be from left edge to right edge of the breast.
¡¤
One or both
breasts may be scanned depending on the clinical circumstances.
¡¤
Make field of
view large enough to include axilla to assess lymph
nodes.
Series 3: Axial
Inversion recovery (IR)
This sequence is helpful for differentiating the
cysts from tumor or fibrosis.
Series 4&5: 3D Gd high temporal resolution
¡¤ This is the main sequence to
identify and characterize malignant lesions.
¡¤ The scan plane may be
sagittal for a single breast or axial for both breasts. With ¡®Vibrant¡¯ it is
possible to prescribe 2 separate volumes, one for each breast. Coronal can also
cover both breasts but does not correspond to a standard mammographic
view.
¡¤ Keep FOV as small as possible but include both
breasts. This helps to ensure homogeneous fat saturation and optimal spatial
resolution.
¡¤ If the # of scan locations
or the phase encoding steps are increased, scan time will increase and the
temporal resolution will be decreased. Longer
scan time generally gives higher spatial resolution as a trade off to high
temporal resolution. In the
¡¤
All pre, during
and post-Gd acquisitions should be done in the same series to facilitate
optimal subtraction technique. It is important to turn on the multiphase option
to ensure that the scanner memory can accommodate the number of post contrast
sequence planned.
¡¤ It is very important that
the patient does not move between the pre, during and post-Gd scans.
¡¤ To minimize the chance of
motion, be sure to start the IV line before performing the pre-contrast
acquisition. In general, the IV should be placed before the patient
enters the magnet because the prone position can make starting the IV extremely
difficult.
¡¤ This sequence is
obtained with the ¡°ZIP2¡± option turned on. This allows you to obtain the images
with a 5-6 mm slice thickness but to reconstruct the images at 2.5-3 mm for
interpretative review.
¡¤ Emphasize with the patient the importance of
avoiding coughing, wiggling or other large motions during or in between these
scans.
¡¤ Manually prescan
to ensure the best possible fat saturation (use cstun).
If homogeneous fat suppression is a problem with the larger FOV used for axial
imaging, the scan can be performed without fat suppression and supplemented
with a post processing subtraction technique for optimal visualization of areas
of contrast enhancement. With ¡®Vibrant¡¯ it is possible to optimize field
homogeneity for two regions, one for each breast.
¡¤ As the machine readily
defaults to frequency R/L direction, make sure that the frequency direction is
A/P. If the primary area of interest is in the axillary tail region, you may
consider A/P phase encoding direction with R/L frequency encoding direction.
This is the one exception to frequency A/P because if phase is A/P then cardiac
and respiratory motion creates phase artifact that superimposes on the breasts.
|
Unilateral |
76093 |
|
Bilateral |
76094 |
|
Reimbursable ICD9 Codes |
|
|
Abnormal mammogram |
793.8 |
|
Palpable mass |
611.72 |
Dictation
Template
Patient
History:
1. Clinical abnormalities: palpable lesion? (size, location, duration) nipple discharge?
2. Previous biopsies: date, location, results
3. Hormonal status: Last menstruation date
(menstrual cycle phase), post-menopausal, peripartum,
exogenous hormones, tamoxifen
Comparison
with Previous Studies:
¡¤ Most recent mammogram (date)
¡¤ Previous breast MRI (date)
¡¤ Ultrasound or nuclear medicine study
Technique:
The
patient was imaged in a 1.5 Tesla magnet using a dedicated breast coil.
Sagittal T1 weighted (6 mm), pre, during, and post-Gd 3D-FSPGR (2.5-3 mm) with
fat saturation images were obtained. An initial set of dynamic FSPGR
gadolinium enhanced images were obtained in the axial plane to include both
breasts with eight 3D data-sets acquired at 92 second intervals. IV ¡.. mL of gadolinium bolus was administered in 20-30 seconds
beginning simultaneously with the second dynamic acquisition.
Post processing techniques: MPR/MIP,
time-intensity curves,
subtraction
Findings:
1.
Artifact that affect interpretation
2. Breast composition: fatty,
scattered fibroglandular tissue heterogeneously dense
fibroglandular tissue, extremely dense fibroglandular
tissue
3. Implants: subpectoral, subglandular
4. Presence of abnormal enhancement:
¡¤ Focal enhancement not thought to represent a mass,
focally enhancing mass, linear/linear branching
(smooth, beaded, or irregular), segmental, regional, patchy, diffuse
homogeneous, heterogeneous, clumped, stippled, rim, internal septational enhancement
¡¤ Location
¡¤ Margins: smooth, scalloped, irregular, speculated
¡¤ Shape: round, lobulated,
oval, irregular, stellate
¡¤ Associated findings: edema,
skin retraction, nipple retraction, skin thickening, dilated ducts,
lymphadenopathy, chest wall or skin invasion, architectural distortion.
5. Kinetic Description:
¡¤ Size and location of ROI
measurements. The ¡°functool2¡±
option on the Windows Advantage work station is very useful for graphic
demonstrations of the signal enhancement ratio.
¡¤ Description of the signal intensity/time
curve-initial enhancement pattern, delayed phase pattern
Impression:
Assessment
incomplete
No
abnormal enhancement
Benign
findings
Probably
benign
Suspicious
for malignancy
Highly
suspicious for malignancy
Recommendations:
Additional
imaging studies and/or clinical correlation is needed
No further work-up needed
Follow-up
MRI advised in short term (menstrual cycle/hormonal)
Follow-up
imaging advised 6 months/1 year later
Biopsy
Report template based on the guidelines of the lesion
diagnosis working group ¨C Schnall et all.JMRI;10:982-990. Please see publication for a full
discussion of breast MRI reporting.