Ultrasound Fine Needle Aspiration Biopsy or Core Biopsy

In an ultrasound guided biopsy, ultrasound images are used to help guide the radiologist’s biopsy needle to the site of the suspicious imaging findings, usually a breast mass. Ultrasound is an imaging technique that uses sound waves to produce detailed images of the structures in the breast.

An ultrasound-guided biopsy can be performed using different kinds of needles, which the radiologist will decide which will be most appropriate in your case. A fine needle removes cells (called a fine needle aspiration) while small pieces of tissue samples are removed with a hollow needle (called a core biopsy). A radiologist may also decide to do a core biopsy with an additional feature using vacuum assistance to obtain samples.

For an ultrasound-guided procedure, you will lie on your back on an ultrasound table. You may be asked to raise the arm on the same side as the breast biopsy into a position above your head. This will help get a better quality image of the breast tissue. The ultrasound technologist will locate the mass to be biopsied with the ultrasound images and make a guiding mark on the skin with an ink pen. The skin will then be cleansed with antiseptic. The radiologist will use ultrasound images during the biopsy to give numbing medication.

If a core biopsy is being performed, a small skin incision measuring about ¼ inches (about 6 millimeters) long is made, through which the biopsy needle is inserted. After locating the mass in the breast with ultrasound, the radiologist guides the needle to that area and takes several core samples of breast tissue to be sent to the pathologist for processing and analysis underneath a microscope.

If a fine needle aspiration is being performed, the radiologist guides the needle to the mass with ultrasound to obtain samples.

In the case of core biopsies and some fine needle aspirations, after removal of the biopsy specimens, one or more small metal markers measuring about ⅛ inch long (3 millimeters) are usually placed in the breast to mark the biopsy site in case surgery is needed at a later time. There are no known harmful effects from the metal markers, but occasionally the marker moves to a site in the breast that is some distance away from the biopsy site. The markers do not set off metal detectors in the airport, are safe for future MRI, and are made of metals that have been used in other implantable devices.

After the biopsy is completed, firm pressure is placed over the biopsy site to help control the small amount bleeding that occurs during and following the biopsy. A bandage will be applied at the entry site and instructions for caring for the biopsy site are explained to you. A light mammogram may be performed after the biopsy.