Imaging-Guided Localization Procedures (Needle Localization Procedures)
The radiologists at Mercy in Baltimore offer imaging-guided localization procedures to help breast surgeons precisely locate and remove cancerous or abnormal breast tissue. Both traditional needle localization as well as wireless localization procedures are offered at Mercy to provide complete and comprehensive treatment for breast cancers and abnormalities.
What is a Localization procedure?
If your breast biopsy results indicate a cancerous or precancerous abnormality, surgery is usually recommended to totally remove that area of tissue. If the abnormality is not palpable (cannot be felt on physical exam) it is often necessary to perform a localization procedure prior to surgery. This is a way to accurately target the exact area of abnormality for the surgeon to remove.
This procedure is performed prior to surgery (sometimes on the same day of surgery) to assist the surgeon in the removal of a cancerous or precancerous abnormality that cannot be felt on physical exam. The goal is to provide a guide or marker so the surgeon can remove the exact area of concern.
These procedures are typically performed by a radiologist in The Center for Women's Imaging at Mercy. In some cases, the needle localization may be performed by the surgeon in the operating room using ultrasound guidance.
Following the localization, the breast surgeon is able to follow the guide into the breast to remove the specific area of abnormality. Once the tissue is removed, X-ray images of the area are obtained in the operating room and both the surgeon and radiologist review the images to ensure the correct area of tissue has been removed.
What types of Localization procedures are offered at Mercy?
Your radiologist and breast surgeon will work together to determine the most appropriate localization for your particular case. Localization options include:
- Wireless Localizations
- Smart Clip - a tiny clip placed in the breast which leads the surgeon to the area of concern in a GPS-like fashion
- Magseed - a grain-sized marker placed in the breast, leading the surgeon to the area of concern with a signal that can be detected with a special probe
- Wire Localization - a thin wire placed into the breast to help guide the surgeon to the area of concern
The clip, seed or wire is inserted into the precise position to identify the area of concern in the breast by using:
How is a Mammography-Guided Needle Localization performed?
Typically, the patient is seated during this procedure and the breast is held in compression in the mammography machine. The compression paddle used for localization has an open area in the center, which allows passage of the needle.
Mammography images are obtained to see the area of concern and a grid is used to calculate the precise location of the abnormality.
The skin is cleansed with an antiseptic solution and a small amount of local anesthetic is given to numb the area. A hollow needle is then placed in the breast and images are obtained to document accurate positioning of this needle.
A small amount of temporary blue dye is injected into the breast tissue (this aids the surgeon in visualizing the area during the operation). A very thin wire is then placed through the needle and the needle is removed.
Final mammography images are taken to document the wire position and these images are sent with the patient to the operating room for the breast surgeon. The wire typically causes no pain and is removed when surgery is performed later the same day.
How is an Ultrasound-Guided Needle Localization performed?
During this procedure, the patient lies on her back on the ultrasound exam table. An ultrasound is used to locate the area of abnormality in the breast.
The skin is cleansed with an antiseptic solution and local anesthetic is injected into the skin and breast tissue to numb the area.
Using ultrasound guidance, the doctor places a hollow needle into the breast, directing it to the area of abnormality. A small amount of temporary blue dye is injected into the breast tissue (this aids the surgeon in visualizing the area during the operation). A very thin wire is then placed through the needle and the needle is removed.
Limited mammography images are taken to document positioning of the needle and both the ultrasound and mammogram images are sent with the patient to the operating room for the breast surgeon. The wire typically causes no pain and is removed when surgery is performed later the same day.
What is an MRI-Guided Needle Localization?
For this procedure the patient lies face down on the MRI exam table with her breasts suspended below the table in a “breast coil,” which helps to hold the breast still.
Preliminary MRI is performed after the patient receives an IV injection of a contrast agent and the radiologist reviews the images to locate and target the area of concern. A computer system aids the radiologist in calculating the exact location of the abnormality.
The skin is cleansed with an antiseptic solution and local anesthetic is injected into the skin and breast tissue to numb the area. A hollow needle is placed into the breast and directed toward the area of abnormality.
MRI images are obtained to document that the needle is in good position. A small amount of temporary blue dye is injected into the breast tissue (this aids the surgeon in visualizing the area during the operation). A very thin wire is then placed through the needle and the needle is removed.
Limited mammography images are performed at the end of the procedure to document the wire position. The wire typically causes no pain and is removed when surgery is performed later the same day.
What is a Wireless Localization?
Newer alternatives have been developed recently to address some disadvantages related to the traditional wire localization procedures. These disadvantages are primarily related to the inconvenience of requiring wire insertion on the same day as surgery, which may result in operating room delays and pre-surgical patient anxiety as well as the possibility of movement of the wire.
Mercy offers a wireless localization, which involves placement of a small non-radioactive stainless steel marker device (sometimes known as Magseed or Smart Clip) into the abnormal tissue using mammogram or ultrasound guidance. The device is then detected during surgery by a special probe which guides the surgeon in a GPS-like fashion to the exact position of the tumor. This has several potential advantages which include:
- Ability to place the device at any time prior to surgery
- Once the seed or clip is placed, there is no discomfort and it does not change position
- In selected cases, potential for more accurate removal of the abnormal tissue
Another major reason for development of alternative methods of localization is that some cases require a surgeon to remove a specific diseased lymph node in the underarm (axillary) region. This most often occurs when a patient has a more locally advanced breast cancer which is best treated with chemotherapy prior to surgery.
Many of these cancers respond well to chemotherapy treatment but removal of the diseased lymph node is still required for successful treatment. These axillary lymph nodes are not easily localized using traditional wire procedures. Placement of this wireless device into a diseased lymph node using ultrasound guidance is typically a very accurate way to guide a surgeon to the specific lymph node which requires removal.
How is a Wireless Localization performed?
Your surgeon and breast radiologist will consult together to determine if a wireless localization device is appropriate for your particular case. The wireless localization can be scheduled well in advance of your surgery date and can be performed at The Center for Women's Imaging at Mercy and Mercy Personal Physicians at Lutherville.
A wireless localization is performed by a breast radiologist and technologist using either ultrasound or mammography guidance.
The skin is cleansed with an antiseptic solution. Local anesthetic is injected into the skin and breast tissue to numb the area.
Once the radiologist has visualized the area of abnormality, the sterile wireless device is then inserted into the abnormal area of tissue using a hollow needle device. A post-placement mammogram is performed to document accurate positioning of the wireless device. The patient may return home and resume all normal activities until the day of surgery.
Removal of the wireless localization device is performed at the time of surgery. The surgeon uses a special detection probe to locate the seed or clip and to guide the removal of the abnormal tumor or lymph node with the seed or clip within it.
While in the operating room, an X-ray image of the removed tissue will be taken to document that the targeted tumor/node and seed/clip have been successfully removed. That X-ray will be reviewed by both the surgeon and breast radiologist.