US-guided core needle biopsy of the breast: technique and pitfalls.

When core needle biopsy of the breast is performed with ultrasound (US) guidance, the curvature of the breast is used to advantage. The breast is entered from the periphery; this approach allows one to avoid chest wall injury and improves needle visualization. Bringing the needle to the lesion by using a sweeping motion while keeping the transducer position relatively fixed will expedite the biopsy. Standard techniques are modified for evaluation of difficult lesions. Mobile lesions can be fixed with the palm of the operator's hand. Deep lesions can be lifted away from the chest wall with the tip of the needle. For lesions in large breasts, a steeper angle of approach may be necessary but can be matched with the transducer to improve needle visualization. Careful correlation with the mammogram will ensure that the corresponding sonographic abnormality is sampled. Although complications are uncommon, hematoma or infection may occur after the procedure. With practice, application of standard and modified techniques can result in efficient and accurate US-guided core needle biopsy of the breast.