Breast Imaging at Yale

[Breast MRI] [Breast Ultrasound] [Core Needle Biopsy] [Needle Localization] [Mammography]

Breast MRI

Magnetic Resonance Imaging (MRI) is a useful tool in the management of breast disease. While not appropriate for everyone, it can be helpful in patients with difficult mammographic findings, for patients with cancer, and for the evaluation of breast implants. Recent studies have shown that MRI can be useful in detecting cancers in young patients, those with dense tissues, and those with the BRCA1/2 genetic mutations.

Detection of lesions with MRI depends on differentiation of the tissue before and after intravenous contrast material administration. Areas that ‘enhance’ are examined more closely. Not all areas that take up cancer will prove to be cancer, but if an area enhances on MRI, further studies may be necessary. This may include additional mammographic images, ultrasound, or biopsy. Follow up imaging studies are also usually necessary.

In the images below, breast cancer is visible using breast MRI.

When necessary, biopsy can be performed with MRI guidance. (see Core Needle Biopsy and Needle Localization)

Breast Ultrasound

Ultrasound is an invaluable tool in the work up of breast abnormalities. Ultrasound is used to further assess areas found on mammography, MRI, or palpable findings. It is also used as the guidance method for many biopsies.

Sonography uses sound waves, so there is no radiation involved. The breast does not have to be compressed. The patient can lie on her back. The transducer is pressed lightly on the skin, so the technique is not painful. A breast ultrasound can usually be performed in about 5 minutes.

Ultrasound can determine if a mass is a cyst, a solid tumor, or normal tissue.

In the two images below, the breast ultrasound shows a cyst on the left and cancer on the right.

If biopsy is required, it can be performed easily with ultrasound guidance (see Core Needle Biopsy and Needle Localization)

Core Needle Biopsy

Core needle biopsy is the primary technique used for diagnosis of most breast lesions. Core needle biopsy saves many patients from undergoing surgery. The majority of lesions sampled will prove to be benign. For those patients found to have cancer, surgery can be planned in advance.

Core needle biopsy can be performed with different methods of guidance:

Stereotactic

Ultrasound

Magnetic Resonance Imaging

PREPARATION

Before a core needle biopsy, Yale asks that you review this information about core needle biopsies.

Prior to biopsy, it is advisable to refrain form taking aspirin or ibuprofens for at least 5 days. This will decrease the chance of bleeding during the procedure. Patients can eat and drink as usual.

A nurse and radiologist will discuss the procedure in detail and answer any questions. The patient must sign a consent form prior to starting the procedure.

STEREOTACTIC BIOPSY

Stereotactic biopsy is performed with digital (computerized) mammographic guidance. Patients lie on their stomach on a cushioned table. There is a hole in the middle where the breast protrudes through. The breast is gently compressed to maintain a stable position and allow accurate targeting and needle placement. Images are obtained in pairs (i.e. stereotactic). The doctor uses the pair of images to target the lesion. After the skin is cleansed, local anesthetic is administered through a small needle. Then the core needle is inserted and images are again obtained to document good positioning. The needle gets into sampling position by advancing quickly in the breast. A loud click is heard and a pinch might be felt when this happens. When the needle is in final position, the samples are obtained with the use of vacuum suction. In general, twelve samples are obtained. This process only takes a few minutes.

For calcification lesions, the technologist will take an x-ray of the core samples to determine whether the lesion has been adequately sampled. This takes an additional few minutes. Some small lesions may be completely removed by the needle sampling procedure. In these cases, a tiny metallic clip may be inserted through the needle at the end of the procedure. This marks the area in case further surgery is necessary.

When the procedure is complete, the needle is withdrawn form the breast, and compression is applied to stop any bleeding. A small sterile strip is applied to the skin at the entry site. The patient may sit with an ice pack on the breast for a few minutes after the procedure.

After the procedure two mammographic images are obtained to check the biopsy site before the patient leaves.

ULTRASOUND BIOPSY

Ultrasound-guided biopsy is performed with the patient lying on her back. After the skin is cleansed, local anesthetic is administered through a small needle. The core needle is then inserted to the area using ultrasound to guide. A loud click is heard as the sample is being obtained. Between 3 to 5 samples are usually obtained. The needle is withdrawn from the breast each time to collect the sample.

In some cases, a vacuum suction device may be used to obtain samples. This is inserted only once to the area of interest, and the samples are collected outside.

Both methods take only a few minutes to complete. Compression is applied to stop any bleeding. A sterile strip is placed over the skin nick.

MAGNETIC RESONANCE IMAGING (MRI) BIOPSY

For lesions that are found only on MRI of the breast, (not seen on mammogram or ultrasound), core needle biopsy can be performed with MRI guidance. Identification of lesions on breast MRI is dependent on uptake of intravenous contrast. Thus prior to the procedure an IV line will be inserted. Contrast material can then be administered while the patient is in the machine.

The patient lies on her stomach on the table and the breast falls into a plastic holder, which is gently compressed for immobilization. After the lesion is found, the skin is cleansed and local anesthetic is administered through a small needle. The core needle is then introduced. Documentation of accurate position depends on repeat MR scans. Thus, the patient is repeatedly slid in and out of the bore of the magnet. When the needle is in good position, the sampling process begins. The sampling procedure takes less than a minute. In some cases a small metallic clip may be inserted to mark the area for future localization. When the procedure is finished, the needle is withdrawn and compression is applied.

POST BIOPSY

This information is sent home with patients after having a biopsy.

As the core needle biopsy procedure is minimally invasive, patients can return to their normal activities immediately following, including returning to work. Only heavy lifting or vigorous upper extremity activities should be avoided.

Results of the biopsy are usually available in 2-3 days. The patient will receive a phone call form either the radiologist, nurse, or their clinician.

Needle Localization

Needle/Wire localization is performed prior to surgery for lesions that are not palpable. This allows the surgeon to localize and remove the correct amount of breast tissue.

Needle localization can be performed with mammographic, ultrasonographic, or MRI guidance. For mammographic lesions, the breast is compressed just like a regular mammogram. Unlike routine mammography, however, the patient is seated in a chair for the procedure. When the area is identified, the skin is cleansed, local anesthetic is given, and a small needle is inserted into the breast. A mammogram image is obtained, the breast is released, and compression is applied again from a different direction. If the needle is seen to be in good position, a thin wire is inserted, and the needle is withdrawn.

For lesions that are seen with ultrasound, the needle localization can be performed without mammographic compression. The patient can lie on her back. The same process of skin cleansing, local anesthetic administration, needle insertion, and wire exchange is performed, using the ultrasound probe to guide the process.

For lesions identified by MR only, needle localization has to be performed in the magnet. This involves repetitive scanning before and after intravenous injection. The same steps for needle/wire insertion are followed.

For all methods of localization, after the procedure is completed, the wire will be measured and taped to the skin to prevent movement. The wire will be removed by the surgeon in the operating room.

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