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field strength:
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1.5 T or 3 T
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coil:
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dedicated bilateral multichannel breast coil with immobilization device
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examination protocol
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The recommended standard is an axial 3D-GE sequence (in-phase) with or without fat
suppression with 1 series before and at least 3 series after contrast agent administration
with a temporal resolution of the individual sequences of ≤ 2 minutes and a total
examination time after contrast agent administration of at least 5 minutes. Other
techniques (e. g. coronal 3 D, axial 2 D) can continue to be performed at centers
with significant experience with the technique but are not generally recommended.
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Paramagnetic Gd contrast agent, weight-adapted simple standard dose, if possible use
of contrast agents with a low NSF risk or only in the case of GFR ≥ 30 ml/min/1.73 m².
If possible, cubital access, preferably automated injection (injection speed 2 – 3 ml/s),
subsequent injection of 20 ml NaCl.
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Additional T2-weighted sequences prior to contrast agent application (alternatively
SE, IR, or FSE/TSE sequences with or without fat suppression) can be helpful in the
differential diagnosis of unclear changes and for correlation with other examination
methods.
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On a slice plane ≤ 1 mm × 1 mm, slice thickness < 3 mm.
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hormones:
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Exogenous hormone therapy (e. g. hormonal contraception, hormone replacement therapy)
can result in assessment limitations with reduced sensitivity and specificity in MRI.
In the case of diagnostic difficulties, the examination can be repeated after discontinuation
of hormone therapy. When using MRI for early detection in asymptomatic women in a high-risk
situation, hormone therapy should be discontinued for at least 4 – 6 weeks prior to
MRI examination.
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time of examination
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Second week of cycle (excluding preoperative staging).
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Examination ideally within the first four weeks after surgery or after a wait period
of at least 6 months after surgery.
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In the case of an irradiated breast, a wait period of at least 12 months after radiation
should be observed if possible. However, if indicated, it can also be helpful to perform
MRI within the first 12 months after radiation therapy.
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postprocessing:
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Subtraction images and MIP projections of dynamic sequences. An evaluation of contrast
enhancement over time either by manual ROI placement or with the help of corresponding
evaluation software can be helpful for better lesion characterization. In the case
of manual ROI placement, the measurement should be performed in the region of the
greatest contrast enhancement in a lesion. At the same time a sufficient ROI size
(e. g. at least 3 pixels) should be ensured.
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storage:
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Digital archiving of the examination, option to store the examination on CD/DVD.
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reporting:
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Description and evaluation of motion artifacts and the background activity of the
glandular parenchyma. Previous breast diagnostic findings should be integrated in
the MRI findings to provide a cumulative evaluation with recommendations for the further
course of action. Both the contrast enhancement behavior in the dynamic examination
and the morphology of the lesion should be taken into consideration for the evaluation
of the malignancy of a lesion.
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interventions:
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For the case that a suspicious lesion seen on MRI in the region of the breast cannot
be seen via mammography or a targeted second-look ultrasound, it must be possible
to perform MRI-supported intervention on-site or at an external center on the basis
of a written cooperation agreement.
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