Breast MR/procedures Flashcards
Indications for breast MRI (6)
Implant evaluation
axillary mets w/ unknown primary
extent of disease
assessing response to therapy
diagnostic delemma
high risk screening
- Who gets a screening MR?
- Which risk model do you use?
- People w/ lifetime risk >15-25%
People who got 20Gy of radiation to chest
- Use Tyrer Cuzickrisk model because it includes family history. The “Gail” risk model does not.
6 sequences that you use for breast MR
T2 w/ FS
T1 Pre w/ FS
T1 Post
Saggital
Subtracted
MIP
- Flaring artifact
- How to fix it
Non-uniform fat suppression when breast tissue is very close to coil elements.
This artifact is not related to fat suppression.
You have to put padding b/w the breast tissue and coil elements.
Background parenchymal enhancement
- When in cycle should you scan in order to minimize BPE
- what other factors effect it?
- Days 7-14
- Hormone therapy (should be stopped)
Serms decrease BPE
Tamoxifen rebound results in increased BPE
-lumpectomy and radiation
Does nipple enhance on Breast MR?
Yes. Enhancement is normal
Defninitition of “foci” in MR
Dot of enhancement (<5mm). Too small to characterize.
If there are many foci, then it is probably BPE
- What does it mean if mass/foci in MR is T2 bright?
- What is the one exception?
- Benign things that enhance (name 3)
- T2 bright = BR2
- Mucinous (colloid) cancer
- fibroadenoma, Papilloma, Lymph nodes
Appearance of firoadenoma on MR
Circumscribed round/oval mass
Variable on T2
On post-contrast, it can enhance, and have non-enhancing septations
If a lesion is not T2 bright, then what do you look at?
- Mass margin should be evaluated on the first post-contrast series. What border feature is most predictive of malignancy?
- Look at morphology, then kinetics
- Spiculated
- Non-mass like enhancement is classic imaging for what?
- It is described by distribution. The distribution is its most predictive feature. Which distributions are bad?
- DCIS is Classic, but it can also represent IDC
- Segmental is worst distribution. Linear, and focal distribution is bad.
BiRADS - MR lexicon
- Shape - 3
- Margins - 3
- Enchancement - 4
- Round, oval, irregular
- Circumscribed, spiculated, irregular
- Homogenous, heterogenous, rim, Dark internal septations.
BIrads - MR lexicon for NME
- Disribution - 6
- Internal enhancement - 4 - (which is the wort kind)
- Focal, segmental, linear, regional, multiple regions, diffuse
- Homogenous, heterogenous, clumped, clustered ring
Clustered ring is the worst kind.
2 types of breast implants. 2 locations.
- Saline and silicone (can’t see through silicone on Mammo)
- For Silicone, you body will form a fibrous capsule around implant. - subglandular/retromammary, subpectoral/retropectoral
- Saline -types of ruptures
- Types of silicone ruptures
appearance on Mammo, u/s and MRI
*if you see silicone in a lymph node, you need to recommend MRI to evaluate for extracapsular rupture.
- Saline - no capsule (no such thing as ‘intracapsular rupture”)
- Silicone: both intra and extra capsular rupture.
mammo: You can’t see intra on mammogram.
u/s: extracapsular creates snowstorm appearance
intracapsular creates ‘step ladder’ appearance.
MRI: intracapsular has linguine sign
What type of mammo views do you need to get with implants
4 views of each breast. CC, MLO, and implant displaced CC and MLO.
When can you BR-0 an MR study?
Never.
Unless the study was technically limited.
Can you BR3 a solitary focus on MRI
If it is solitary focus with persistent kinetics on baseline exam, you can give it a BR3
Describe Cowden Syndrome (4 things)
Bowel hamartoma, follicular thyroid cancer, Lhermitte Duclos, breast cancer
- u/s biopsy - how to position
- What should be needle projectory?
- roll breast away from lesion (thin the tissue)
Raise ipsilateral arm.
- parallel to chest wall
- For ultrasound biopsy of a ‘disapearing lesion,’ which part of the lesion swould you biopsy?
- If there are 2 lesions and 1 of them is obvious/large and the other is less obvious, which do you biopsy first?
- biopsy the posterior part first, becase then you can still see the anterior part.
- Biopsy the one you see worse first. This is because then if things get distorted, you can probably still see the big one.
Situations when a stereo biopsy is difficult
Thin breast (<2-3cm compressed thickness)
Lesions too close to skin
subareolar lesions
posterior lesions
How do you calculate depth when doing a stereo biopsy?
Get a +15 degree and -15 degree images. Then the computer will calculate depth (z axis)
What is stroke margin?
What do you want, a positive or negative stroke margin?
Distance between when where the needle is supposed to end after the throw, and the skin on the opposite side
Positive stroke margin: You still have space between needle throw and skin
Negative stroke margin (bad): your needle through will puncture skin
Stereo targeting error: how can you tell X vs. Y vs. Z axis error?
on X axis, images will project with different relationship to the lesion (ex. one projects over the lesions, when the other is off the lesion)
On Y axis, both images will be either superior or inferior to the lesion
On Z axis, both images will either be not deep enough, or too deep
What is management of high risk lesions?
Surgical excision
A 39-year-old female is scheduled for a contrast-enhanced breast MRI for high-risk screening evaluation. She undergoes laboratory testing for renal function due to her history of diabetes mellitus. Her laboratory results are creatinine of 1.8 mg/dL and a calculated GFR of 28 mL/min/1.73 m 2. No prior laboratory data are available to review. Which of the following is the most appropriate next step in the evaluation of this patient?
a discussion of the patient’s risk-benefit ratio with the referring physicians is necessary to determine if the examination is essential. If intravenous gadolinium-based contrast administration is needed, it is recommended that one use the lowest possible dose to obtain a diagnostic study.
The Food and Drug Administration (FDA) has determined that the risk for patients with chronic insufficiency is greatest when the estimated glomerular filtration rate (eGFR) is <30 mL/min/1.73 m 2.
Nephrogenic systemic fibrosis (NSF) is a rare but serious systemic disease characterized by fibrosis of the skin and other tissues throughout the body. The first report on NSF was published in 1997, and there is increasing evidence that this condition is associated with renal failure and the administration of large amounts of gadolinium.
motion artifact
when should you bracket cancer when using wire localization
when cancer is >2.5 cm
