Breast ultrasound

Breast ultrasound is an important modality in breast imaging. It is the usual initial breast imaging modality in those under 30 years of age in many countries.

In assessing for malignancy, is important to remember that one must use most suspicious feature of 3 modalities (pathology, ultrasound, mammography) to guide management.

  • breast ultrasound is targeted to a clinical problem
  • reasonable sensitivity but poor specificity
  • may have a place in screening women at high risk or with MMG dense breasts
Breast ultrasound technique
  • lighting
  • patient positioning: support elbow, flat, supine
  • ergonomics
  • probe: linear array 7-13 MHz
  • scanning: radial/antiradial
  • clock face with distance from nipple
  • only caliper things that are REAL
  • correct depth (skin to pectoral fascia) and correct focal zone (up to 2 is OK)
  • dynamic range: some settings can make a cystic lesion look solid and vice versa
Scanning technique
  • compression and angulation of probe to heel toe to sharpen up the edges of a lesion
  • traps for beginners
    • edge refraction: from vessels, Cooper's ligaments, edge of cysts
    • focal fat locules
    • anisotropy
  • compound Imaging and resolution
    • cleans up speckles
    • gives between edge definition
  • harmonics
    • transmits at 1 frequency
    • receive only multiples of the frequency
    • most noise is generated near the transducer due to reverberation
Use of breast ultrasound 
  • to evaluate a young (usually under 30 years of age) or pregnant patient who is symptomatic
  • to evaluate a palpable lump with negative or equivocal mammographic findings
  • detect lesions in lower contrast field
  • can help to distinguish between benign vs malignant characteristics
  • for guiding biopsy
  • for evaluation of breast implants for rupture
Cysts

See main article on breast cysts:

  • edge is the MOST important feature
    • no rind
    • pencil thin
    • well defined all the way around
  • is it compressible?
  • can you move the inside?
  • is there a solid edge: sometimes color doppler will help
Power Doppler and vocal fremitus
  • to help distinguish malignant from benign tumours
  • get patient to say AHHHH or 99 very loud
  • cancer - vibrations conducted along tumour infiltration into centre, hence color pixels run into centre of tumour and fill it in
  • benign lesions (eg fat lobules) - cannot get power doppler into centre of lesion
  • not a useful test in superficial lesions OR large breasts
Features that are found NOT to be useful in differentiating malignant from benign lesions
  • heterogenicity/homogenicity of texture
  • normal/enhanced through transmission, e.g. mucinous cancers
  • being iso-mildly hypoechoic
  • maximum diameter
Classification of nodules
  • benign: no malignant features, combinations of benign findings
  • indeterminate: no malignant findings; no combination of benign findings (needs biopsy)
  • malignant: one malignant feature (needs biopsy)

Potential pitfalls in breast ultrasound in practice

Always correlate the mammogram images before the ultrasound is done. The operator must know where the lesion is located in the breast and the nature of the lesion. What are you looking for and where is it located?

If you work with ultrasound technologists, review by the radiologist in real time is almost always required unless for the simplest of overtly benign breast pathology. In every day practice, do not be tempted to review static images of breast pathology without looking in real time. This is a very significant potential pitfall for the misdiagnosis of breast pathology.

With the high resolution of the newest apparatus, consider doing ultrasound even if you are working up microcalcifications. In cases where you find them on ultrasound, you may be able to supply a tissue diagnosis and save the inconvenience of mammotome biopsy for the patient.

Screening ultrasound

With more accent now being placed on characterising breast density, more authors feel there is a place for screening ultrasound in the dense (> 75% ) breast. In Connecticut ultrasound of the dense breast is now mandated and paid for by the state. There is good evidence that in this group of patients the yield of ultrasound in picking up cancers is almost as high as mammography itself in the range of an additional 3-4/1000 cancers found (Berg, ECR, 2013). In the context of screening for breast cancer, ultrasound in capable hands will find low grade DCIS that may not be visible on mammography. "Second look" ultrasound after breast MRI will yield a positive finding in about 56% of cases.


Breast imaging and pathology
Share Article

Article Information

rID: 2681
System: Breast
Section: Physics
Synonyms or Alternate Spellings:
  • Breast Ultrasound
  • Ultrasound of the breast
  • Ultrasound evaluation of the breast
  • Ultrasound evaluation of the breasts
  • Full breast Ultrasonography

Support Radiopaedia and see fewer ads

  • Drag
    BIRAD I I
    Case 1: BIRADS II lesion
    Drag here to reorder.
  • Drag
    no posterior enha...
    Case 2
    Drag here to reorder.
  • Drag
    Case 3: BIRADS V lesion
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.