Breast Ultrasonography (US) and Breast Procedures

1

What are the labeled structures on the ultrasound image in Figure 10-1 ?

The structures are skin (A), subcutaneous fat (B), glandular tissue (C), fat (D), muscle (E), and rib (F).

2

What type of transducer should be used to perform breast US?

A linear array transducer should be used. It should ideally have a frequency of 10 MHz or greater.

3

List the indications for targeted breast US after a mammographic evaluation.

• To evaluate a palpable abnormality further. In patients presenting with palpable breast masses, even if the mammogram results are negative, a targeted sonographic evaluation of the palpable area is a necessary part of the evaluation.

• To characterize a mammographic finding or abnormality. For example, if there is a new or enlarging mass seen on mammography, sonography is needed to characterize the mass. If the mass is demonstrated to be a cyst on sonography, nothing further needs to be done. But, if there is an enlarging or new solid mass, a biopsy is needed. As the mass is visible on sonography, the biopsy may be performed under ultrasound guidance.

4

When would breast US be indicated without obtaining a mammogram first?

• In patients who are younger than 30 and in pregnant patients, it is recommended to start with breast US. For other patients presenting with palpable masses, mammography should be obtained first, with the following exceptions. At our institution, a mammogram is obtained first in women who are older than 30. To evaluate the palpable abnormality further, US follows mammography. If the patient is younger than 30, US is performed first. Age 30 is an arbitrary number; different institutions may have a different cutoff age.

• In patients who have had a mastectomy, there is not enough tissue to obtain a mammogram. If there is a palpable area, sonographic evaluation should be performed.

• In women who are lactating, sonography may be performed first.

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