Evaluation of the axilla is a challenging task for the clinician that treats breast cancer. Clinical examination is difficult, and imaging studies have not been shown to be very useful in differentiating benign from malignant lymph nodes. Accurate evaluation of the axilla can help with the evaluation of palpable masses as well as acquiring targets for fine‐needle aspiration, which can avoid unnecessary sentinel node procedures.

Mammography can detect the presence of large axillary lymph nodes but cannot adequately assess their internal structure. MRI studies using gadolinium contrast can be helpful in the evaluation of lymph nodes by looking at the timing of contrast uptake and washout. The test is expensive and abnormal lymph nodes seen on MRI are difficult to localize for biopsy.

Hand‐held ultrasound has been used to evaluate lymph nodes for size as well as he internal morphology. Although no definitive classification systems for lymph node morphology have been reported, the assessment of lymph nodes may be performed by looking for suspicious morphologic patterns seen on ultrasound that relate to the relationship of the hilum to the rest of the node.(5) Hand‐held axillary ultrasound, of course, requires practice and must usually be performed by a clinician who is experienced in the technique.

Recently, a new sonographic technique, has been introduced which greatly facilitates the evaluation of the axilla. The technique involves the use an automated ultrasound probe that images a wide field of view.

This allows imaging of the entire axilla from above the axillary vein down to the axillary tail of the breast, between the pectoralis minor muscle and the latissimus dorsi muscle. The anatomic relationship of all these structures is preserved allowing the surgeon to accurately localize any suspicious findings.