Tuesday, June 1, 2010

Breast Ultrasound

Ultrasound-Guided Breast Biopsy

What is Ultrasound-Guided Breast Biopsy?

Lumps or abnormalities in the breast are often detected by physical examination, mammography, or other imaging studies. However, it is not always possible to tell from these imaging tests whether a growth is benign or cancerous.
A breast biopsy is performed to remove some cells—either surgically or through a less invasive procedure involving a hollow needle—from a suspicious area in the breast and examine them under a microscope to determine a diagnosis. Image-guided needle biopsy is not designed to remove the entire lesion, but most of a very small lesion may be removed in the process of biopsy.
Image-guided biopsy is performed when the abnormal area in the breast is too small to be felt, making it difficult to locate the lesion by hand (called palpation).
In ultrasound-guided breast biopsy, ultrasound imaging is used to help guide theradiologist's instruments to the site of the abnormal growth.

What are some common uses of the procedure?

An ultrasound-guided breast biopsy can be performed when a breast ultrasound shows an abnormality such as:
  • a suspicious solid mass
  • a distortion in the structure of the breast tissue
  • an area of abnormal tissue change
There are times when your doctor may decide that ultrasound guidance for biopsy is appropriate even for a mass that can be felt.
Ultrasound guidance is used in four biopsy procedures:
  • fine needle aspiration (FNA), which uses a very small needle to extract fluid or cells from the abnormal area.
  • core needle (CN) which uses a large hollow needle to remove one sample of breast tissue per insertion.
  • vacuum-assisted device (VAD) which uses a vacuum powered instrument to collect multiple tissue samples during one needle insertion.
  • wire localization, in which a guide wire is placed into the suspicious area to help the surgeon locate the lesion for surgical biopsy.

How should I prepare?

You should wear comfortable, loose-fitting clothing for your ultrasound exam. You may need to remove all clothing and jewelry in the area to be examined.
You may be asked to wear a gown during the procedure.
Prior to a needle biopsy, you should report to your doctor all medications that you are taking, including herbal supplements, and if you have any allergies, especially toanesthesia. Your physician will advise you to stop taking aspirin or a blood thinner three days before your procedure.
Also, inform your doctor about recent illnesses or other medical conditions.
You may want to have a relative or friend accompany you and drive you home afterward. This is recommended if you have been sedated.

What does the equipment look like?

Ultrasound scanners consist of a console containing a computer and electronics, a video display screen and a transducer that is used to scan the body and blood vessels. The transducer is a small hand-held device that resembles a microphone, attached to the scanner by a cord. The transducer sends out high frequency sound waves into the body and then listens for the returning echoes from the tissues in the body. The principles are similar to sonar used by boats and submarines.
The ultrasound image is immediately visible on a nearby video display screen that looks much like a computer or television monitor. The image is created based on the amplitude (strength), frequency and time it takes for the sound signal to return from the patient to the transducer and the type of body structure the sound travels through.
One of four instruments will be used:
  • A fine needle attached to a syringe, smaller than needles typically used to draw blood.
  • A core needle, also called an automatic, spring-loaded needle, which consists of an inner needle connected to a trough, or shallow receptacle, covered by a sheath and attached to a spring-loaded mechanism.
  • A vacuum-assisted device (VAD), a vacuum-powered instrument that uses pressure to pull tissue into the needle.
  • A thin guide wire, which is used for a surgical biopsy.
Other sterile equipment involved in this procedure includes syringes, sponges, forceps, scalpels and a specimen cup or microscope slide.

How does the procedure work?

Ultrasound imaging is based on the same principles involved in the sonar used by bats, ships and fishermen. When a sound wave strikes an object, it bounces back, or echoes. By measuring these echo waves it is possible to determine how far away the object is and its size, shape, and consistency (whether the object is solid, filled with fluid, or both).
In medicine, ultrasound is used to detect changes in appearance of organs, tissues, and vessels or detect abnormal masses, such as tumors.
In an ultrasound examination, a transducer both sends the sound waves and records the echoing waves. When the transducer is pressed against the skin, it directs small pulses of inaudible, high-frequency sound waves into the body. As the sound waves bounce off of internal organs, fluids and tissues, the sensitive microphone in the transducer records tiny changes in the sound's pitch and direction. These signature waves are instantly measured and displayed by a computer, which in turn creates a real-time picture on the monitor. One or more frames of the moving pictures are typically captured as still images.
Using an ultrasound probe to visualize the location of the breast lump, the radiologist inserts a biopsy needle through the skin, advances it into the mass and removes tissue samples. If a surgical biopsy is being performed, ultrasound may be used to guide a wire directly into the mass to help the surgeon locate the area for excision. With continuous ultrasound imaging, the physician is able to view the biopsy needle or wire as it advances to the location of the lesion in real-time.

How is the procedure performed?

Image-guided, minimally invasive procedures such as ultrasound-guided breast biopsy are most often performed by a specially trained radiologist.
Breast biopsies are usually done on an outpatient basis.
You will be positioned lying face up on the examination table or turned slightly to the side.
A local anesthetic will be injected into the breast to numb it.
Pressing the transducer to the breast, the sonographer or radiologist will locate the lesion.
A very small nick is made in the skin at the site where the biopsy needle is to be inserted.
The radiologist, constantly monitoring the lesion site with the ultrasound probe, will insert the needle and advance it directly into the mass.
Tissue samples are then removed using one of three methods:
  • In a fine needle aspiration, a fine gauge needle and a syringe withdraw fluid or clusters of cells.
  • In a core needle biopsy, the automated mechanism is activated, moving the needle forward and filling the needle trough, or shallow receptacle, with 'cores' of breast tissue. The outer sheath instantly moves forward to cut the tissue and keep it in the trough. This process is repeated three to six times.
  • With a vacuum-assisted device (VAD), vacuum pressure is used to pull tissue from the breast through the needle into the sampling chamber. Without withdrawing and reinserting the needle, it rotates positions and collects additional samples. Typically, eight to 10 samples of tissue are collected from around the lesion.
After this sampling, the needle will be removed.
If a surgical biopsy is being performed, a wire is inserted into the suspicious area as a guide for the surgeon.
A small marker may be placed at the site so that it can be located in the future if necessary.
Once the biopsy is complete, pressure will be applied to stop any bleeding and the opening in the skin is covered with a dressing. No sutures are needed.
A mammogram may be performed to confirm that the marker is in the proper position.
This procedure is usually completed within an hour.

What will I experience during and after the procedure?

You will be awake during your biopsy and should have little or no discomfort. Most women report little or no pain and no scarring on the breast.
When you receive the local anesthetic to numb the skin, you will feel a slight pin prick from the needle. You may feel some pressure when the biopsy needle is inserted.
The area will become numb within a short time.
You must remain still while the biopsy is performed.
As tissue samples are taken, you may hear clicks from the sampling instrument.
If you experience swelling and bruising following your biopsy, you may be instructed to take an over-the-counter pain reliever and to use a cold pack. Temporary bruising is normal.
You should contact your physician if you experience excessive swelling, bleeding, drainage, redness or heat in the breast.
If a marker is left inside the breast to mark the location of the biopsied lesion, it will cause no pain, disfigurement or harm.
You should avoid strenuous activity for 24 hours after returning home, but then usually will be able to resume normal activities.

Who interprets the results and how do I get them?

pathologist examines the removed specimen and makes a final diagnosis. Depending on the facility, the radiologist or your referring physician will share the results with you.

What are the benefits vs. risks?

Benefits

  • The procedure is less invasive than surgical biopsy, leaves little or no scarring and can be performed in less than an hour.
  • Ultrasound imaging uses no ionizing radiation.
  • Ultrasound-guided breast biopsy reliably provides tissue samples that can show whether a breast lump is benign or malignant.
  • Compared with stereotactic breast biopsy (www.RadiologyInfo.org/en/info.cfm?pg=breastbixr), the ultrasound method is faster and avoids the need for ionizing radiation exposure.
  • With ultrasound it is possible to follow the motion of the biopsy needle as it moves through the breast tissue.
  • Ultrasound-guided breast biopsy is able to evaluate lumps under the arm or near the chest wall, which are hard to reach with stereotactic biopsy.
  • Ultrasound-guided biopsy is less expensive than stereotactic biopsy.
  • Recovery time is brief and patients can soon resume their usual activities.

Risks

  • Because the vacuum-assisted device removes slightly larger pieces of tissue than other types of needles, there is a risk of bleeding and forming a hematoma, or a collection of blood at the biopsy site. The risk, however, appears to be less than one percent of patients.
  • An occasional patient has significant discomfort, which can be readily controlled by non-prescription pain medication.
  • Any procedure where the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in 1,000.
  • Doing a biopsy of tissue located deep within the breast carries a slight risk that the needle will pass through the chest wall, allowing air around the lung that could collapse a lung. This is a rare occurrence.

What are the limitations of Ultrasound-Guided Breast Biopsy?

Breast biopsy procedures will occasionally miss a lesion or underestimate the extent of disease present. If the diagnosis remains uncertain after a technically successful procedure, surgical biopsy will usually be necessary.
The ultrasound-guided biopsy method cannot be used unless the lesion can be seen on an ultrasound exam. Clustered calcifications are not shown as clearly with ultrasound as with x-rays.
Very small lesions may be difficult to target accurately by ultrasound-guided core biopsy.
Breast Ultrasound

Play Video Clip (00:02:13)
Video: Your Radiologist Explains Breast Ultrasound
Your Radiologist Explains 
Breast Ultrasound

What is Ultrasound Imaging of the Breast?

Ultrasound imaging, also called ultrasound scanning orsonography, involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body. Ultrasound exams do not use ionizing radiation (as used in x-rays). Because ultrasound images are captured in real-time, they can show the structure and movement of the body's internal organs, as well as blood flowing through blood vessels.
Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions.
Ultrasound imaging of the breast produces a picture of the internal structures of the breast.
Doppler ultrasound is a special ultrasound technique that evaluates blood flow through a blood vessel, including the body's major arteries and veins in the abdomen, arms, legs and neck.
During a breast ultrasound examination the sonographer or physician performing the test may use Doppler techniques to evaluate blood flow or lack of flow in any breast mass. In some cases this may provide additional information as to the cause of the mass.

What are some common uses of the procedure?

  • Determining the Nature of a Breast Abnormality
    The primary use of breast ultrasound today is to help diagnose breast abnormalities detected by a physician during a physical exam (such as a lump or bloody or spontaneous clear nipple discharge) and to characterize potential abnormalities seen on mammography

    Ultrasound imaging can help to determine if an abnormality is solid (which may be a non-cancerous lump of tissue or a cancerous tumor) or fluid-filled (such as abenign cyst) or both cystic and solid. Ultrasound can also help show additional features of the abnormal area. 

    Doppler ultrasound is used to assess blood supply in breast lesions.

  • Supplemental Breast Cancer Screening
    Mammography is the only screening tool for breast cancer that is known to reduce deaths due to breast cancer through early detection. Even so, mammograms do not detect all breast cancers. Some breast lesions and abnormalities are not visible or are difficult to interpret on mammograms. In breasts that are dense, meaning there is a lot of glandular tissue and less fat, many cancers can be hard to see on mammography. 

    Many studies have shown that ultrasound and magnetic resonance imaging (MRI) can help supplement mammography by detecting small breast cancers that may not be visible with mammography. MRI is more sensitive than ultrasound in depicting breast cancer, but not all women can tolerate contrast-enhanced breast MRI. MRI is not offered to all women who may benefit from it. Screening ultrasound can be an alternative to MRI for women who cannot tolerate MRI. If screening MRI is performed, then screening ultrasound is not needed, though ultrasound may be used to characterize and biopsy abnormalities seen on MRI. When ultrasound is used for screening, many abnormalities are seen which may require biopsy but are not cancer (false positives), and this limits its cost effectiveness. 
Ultrasound can be offered as a screening tool for women who:
  • are at high risk for breast cancer and unable to tolerate an MRI examination.
  • are at intermediate risk for breast cancer based on family history, personal history of breast cancer, or prior biopsy showing an abnormal result.
  • have dense breasts.
  • have silicone breast implants and very little tissue can be included on the mammogram.
  • are pregnant or should not to be exposed to x-rays (which is necessary for a mammogram).
Several types of automated devices have been developed for whole breast ultrasound. Further evaluation of such approaches is needed.
  • Ultrasound-guided Breast Biopsy 
    When an ultrasound examination reveals a suspicious breast abnormality, a physician may choose to perform an ultrasound-guided biopsy. Because ultrasound provides real-time images, it is often used to guide biopsy procedures. 

    For more information on this procedure, please refer to the Ultrasound-guided Breast Biopsy page (www.RadiologyInfo.org/en/info.cfm?pg=breastbius).

How should I prepare?

You will be asked to undress from the waist up and to wear a gown during the procedure.

What does the equipment look like?

Ultrasound scanners consist of a console containing a computer and electronics, a video display screen and a transducer that is used to scan the body and blood vessels. The transducer is a small hand-held device that resembles a microphone, attached to the scanner by a cord. The transducer sends out high frequency sound waves into the body and then listens for the returning echoes from the tissues in the body. The principles are similar to sonar used by boats and submarines.
The ultrasound image is immediately visible on a nearby video display screen that looks much like a computer or television monitor. The image is created based on the amplitude (strength), frequency and time it takes for the sound signal to return from the patient to the transducer and the type of body structure the sound travels through.

How does the procedure work?

Ultrasound imaging is based on the same principles involved in the sonar used by bats, ships and fishermen. When a sound wave strikes an object, it bounces back, or echoes. By measuring these echo waves it is possible to determine how far away the object is and its size, shape, and consistency (whether the object is solid, filled with fluid, or both).
In medicine, ultrasound is used to detect changes in appearance of organs, tissues, and vessels or detect abnormal masses, such as tumors.
In an ultrasound examination, a transducer both sends the sound waves and records the echoing waves. When the transducer is pressed against the skin, it directs small pulses of inaudible, high-frequency sound waves into the body. As the sound waves bounce off of internal organs, fluids and tissues, the sensitive microphone in the transducer records tiny changes in the sound's pitch and direction. These signature waves are instantly measured and displayed by a computer, which in turn creates a real-time picture on the monitor. One or more frames of the moving pictures are typically captured as still images.
Doppler ultrasound, a special application of ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of blood cells causes a change in pitch of the reflected sound waves (called the Doppler effect). A computer collects and processes the sounds and creates graphs or color pictures that represent the flow of blood through the blood vessels.

How is the procedure performed?

You will lie on your back with your arm raised above your head on the examining table.
A clear water-based gel is applied to the area of the body being studied to help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin. The sonographer (ultrasound technologist) or radiologist then presses the transducer firmly against the skin in various locations, sweeping over the area of interest or angling the sound beam from a farther location to better see an area of concern.
Doppler sonography is performed using the same transducer.
When the examination is complete, the patient may be asked to dress and wait while the ultrasound images are reviewed. However, the sonographer or radiologist is often able to review the ultrasound images in real-time as they are acquired and the patient can be released immediately.
This ultrasound examination is usually completed within 30 minutes.

What will I experience during and after the procedure?

Most ultrasound examinations are painless, fast and easy.
After you are positioned on the examination table, the radiologist or sonographer will apply some warm water-based gel on your skin and then place the transducer firmly against your body, moving it back and forth over the area of interest until the desired images are captured. There is usually no discomfort from pressure as the transducer is pressed against the area being examined.
If scanning is performed over an area of tenderness, you may feel pressure or minor pain from the transducer.
If a Doppler ultrasound study is performed, you may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured.
You may be asked to change positions during the exam.
Once the imaging is complete, the gel will be wiped off your skin.
After an ultrasound exam, you should be able to resume your normal activities immediately.

Who interprets the results and how do I get them?

A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send a signed report to your primary care physician or the physician who referred you for the exam, who will share the results with you. In some cases the radiologist may discuss results with you at the conclusion of your examination.

What are the benefits vs. risks?

Benefits

  • Most ultrasound scanning is noninvasive (no needles or injections) and is usually painless.
  • Ultrasound is widely available, easy-to-use and less expensive than other imaging methods.
  • Ultrasound imaging does not use any ionizing radiation.
  • Ultrasound scanning gives a clear picture of soft tissues that do not show up well on x-ray images.
  • Ultrasound provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as needle biopsies and needle aspiration.
  • Ultrasound imaging can help detect lesions in women with dense breasts.
  • Ultrasound may help detect and classify a breast lesion that cannot be interpreted adequately through mammography alone.
  • Using ultrasound, physicians are able to determine that many areas of clinical concern are due to normal tissue (such as fat lobules) or benign cysts. For most women 30 years of age and older, a mammogram will be used together with ultrasound. For women under age 30, ultrasound alone is often sufficient to determine whether an area of concern needs a biopsy or not.

Risks

  • For standard diagnostic ultrasound there are no known harmful effects on humans.
  • Interpretation of a breast ultrasound examination may lead to additional procedures such as follow-up ultrasound and/or aspiration or biopsy. Many of the areas thought to be of concern only on ultrasound turn out to be non-cancerous.

What are the limitations of Ultrasound Imaging of the Breast?

  • Ultrasound is one of the tools used in breast imaging, but it does not replace annual mammography and careful clinical breast examination.
  • Many cancers are not visible on ultrasound.
  • Biopsy may be recommended to determine if a suspicious abnormality is cancer or not.
  • Many calcifications seen on mammography cannot be seen on ultrasound. Some early breast cancers only show up as calcifications on mammography.
  • Many facilities do not offer ultrasound screening, and the procedure may not be covered by some insurance plans.
  • It is important to choose a facility with expertise in breast ultrasound, preferably one where the radiologists specialize in breast imaging. Ultrasound depends on the abnormality being recognized at the time of the scan as it is a "real-time" examination. This requires experience and good equipment. One measure of a facility's expertise in breast ultrasound can be found in its ACR accreditation status. Check the facilities in your area by searching the ACR-accredited facilities database.


Stereotactic (Mammographically Guided) Breast Biopsy

What is Stereotactic (Mammographically Guided) Breast Biopsy?

Lumps or abnormalities in the breast are often detected by physical examination, mammography, or other imaging studies. However, it is not always possible to tell from these imaging tests whether a growth is benign or cancerous.
A breast biopsy is performed to remove some cells—either surgically or through a less invasive procedure involving a hollow needle—from a suspicious area in the breast and examine them under a microscope to determine a diagnosis. Image-guided needle biopsy is not designed to remove the entire lesion, but most of a very small lesion may be removed in the process of biopsy.
Image-guided biopsy is performed when the abnormal area in the breast is too small to be felt, making it difficult to locate the lesion by hand (called palpation).
In stereotactic breast biopsy, a special mammography machine uses ionizing radiation to help guide the radiologist's instruments to the site of the abnormal growth.

What are some common uses of the procedure?

A stereotactic breast biopsy is performed when a mammogram shows a breast abnormality such as:
  • a suspicious solid mass
  • microcalcifications, a tiny cluster of small calcium deposits
  • a distortion in the structure of the breast tissue
  • an area of abnormal tissue change
  • a new mass or area of calcium deposits is present at a previous surgery site.
Stereotactic breast biopsy is also performed when the patient or physician strongly prefers a non-surgical method of assessing a breast abnormality.
Stereotactic guidance is used in two biopsy procedures:
  • core needle (CN) which uses a large hollow needle to remove one sample of breast tissue per insertion.
  • vacuum-assisted device (VAD) which uses a vacuum powered instrument to collect multiple tissue samples during one needle insertion.

How should I prepare?

You may be asked to remove some or all of your clothes and to wear a gown during the exam. You may also be asked to remove jewelry, dentures, eye glasses and any metal objects or clothing that might interfere with the x-ray images.
Women should always inform their physician if there is any possibility that they are pregnant. Some procedures using image-guidance are typically not performed during pregnancy because radiation can be harmful to the fetus.
You should not wear deodorant, powder, lotion or perfume under your arms or on your breasts on the day of the exam.
Prior to a needle biopsy, you should report to your doctor all medications that you are taking, including herbal supplements, and if you have any allergies, especially toanesthesia. Your physician will advise you to stop taking aspirin or a blood thinner three days before your procedure.
Also, inform your doctor about recent illnesses or other medical conditions.
You may want to have a relative or friend accompany you and drive you home afterward. This is recommended if you have been sedated.

What does the equipment look like?

The specialized mammography machine used in this procedure is similar to the mammography unit used to produce diagnostic mammograms.
A mammography unit is a rectangular box that houses the tube in which x-rays are produced. The unit is used exclusively for x-ray exams of the breast, with special accessories that allow only the breast to be exposed to the x-rays. Attached to the unit is a device that holds and compresses the breast and positions it so images can be obtained at different angles.
At most facilities, a specially designed examination table will allow you to lie face down with your breast hanging freely through an opening in the table. The table is then raised and the biopsy procedure is performed beneath the table. At other facilities, the procedure may be performed while you sit in a chair.
One of two instruments will be used:
  • A core needle, also called an automatic, spring-loaded needle, which consists of an inner needle connected to a trough, or shallow receptacle, covered by a sheath and attached to a spring-loaded mechanism.
  • A vacuum-assisted device (VAD), a vacuum powered instrument that uses pressure to pull tissue into the needle.
Other sterile equipment involved in this procedure includes syringes, sponges, forceps, scalpels and a specimen cup or microscope slide.

How does the procedure work?

Mammography is a low-dose x-ray system designed to examine breasts.
The special mammography unit used to perform a stereotactic breast biopsy is a digital mammography machine. In digital mammography, as in digital photography, film is replaced by electronic detectors. These convert x-rays into electrical signals, which are used to produce images of the breast that can be immediately seen on a computer screen.
Stereotactic mammography pinpoints the exact location of a breast mass by using a computer and x-rays taken from two different angles. Using these computer coordinates, the radiologist inserts the needle through the skin, advances it into thelesion and removes tissue samples.

How is the procedure performed?

Image-guided, minimally invasive procedures such as stereotactic breast biopsy are most often performed by a specially trained radiologist.
Breast biopsies are usually done on an outpatient basis.
You will lie face down on a moveable exam table and the affected breast or breasts will be positioned into openings in the table.
The table is then raised and the procedure is then performed beneath it. If the machine is an upright system, you may be seated next to the stereotactic mammography unit.
The breast is compressed and held in position throughout the procedure.
A local anesthetic will be injected into the breast to numb it.
Several stereotactic pairs of x-ray images are taken.
A very small nick is made in the skin at the site where the biopsy needle is to be inserted.
The radiologist then inserts the needle and advances it to the location of the abnormality using the x-ray and computer generated coordinates. X-ray images are again obtained to confirm that the needle tip is actually within the lesion.
Tissue samples are then removed using one of two methods.
  • In a core needle biopsy, the automated mechanism is activated, moving the needle forward and filling the needle trough, or shallow receptacle, with 'cores' of breast tissue. The outer sheath instantly moves forward to cut the tissue and keep it in the trough. This process is repeated three to six times.
  • With a vacuum-assisted device (VAD), vacuum pressure is used to pull tissue from the breast through the needle into the sampling chamber. Without withdrawing and reinserting the needle, it rotates positions and collects additional samples. Typically, eight to 10 samples of tissue are collected from around the lesion.
After the sampling, the needle will be removed.
A final set of images will be taken.
A small marker may be placed at the site so that it can be located in the future if necessary.
Once the biopsy is complete, pressure will be applied to stop any bleeding and the opening in the skin is covered with a dressing. No sutures are needed.
A mammogram may be performed to confirm that the marker is in the proper position.
This procedure is usually completed within an hour.

What will I experience during and after the procedure?

You will be awake during your biopsy and should have little or no discomfort. Most women report little or no pain and no scarring on the breast.
Some women find that the major discomfort of the procedure is from lying on their stomach for the length of the procedure, which can be reduced by strategically placed cushions.
When you receive the local anesthetic to numb the skin, you will feel a slight pin prick from the needle. You may feel some pressure when the biopsy needle is inserted.
The area will become numb within a short time.
You must remain still while the biopsy is performed.
As tissue samples are taken, you may hear clicks from the sampling instrument.
If you experience swelling and bruising following your biopsy, you may be instructed to take an over-the-counter pain reliever and to use a cold pack. Temporary bruising is normal.
You should contact your physician if you experience excessive swelling, bleeding, drainage, redness or heat in the breast.
If a marker is left inside the breast to mark the location of the biopsied lesion, it will cause no pain, disfigurement or harm.
You should avoid strenuous activity for 24 hours after returning home, but then usually will be able to resume normal activities.

Who interprets the results and how do I get them?

pathologist examines the removed specimen and makes a final diagnosis. Depending on the facility, the radiologist or your referring physician will share the results with you.

What are the benefits vs. risks?

Benefits

  • The procedure is less invasive than surgical biopsy, leaves little or no scarring and can be performed in less than an hour.
  • Stereotactic breast biopsy is an excellent way to evaluate calcium deposits or tiny masses that are not visible on ultrasound.
  • Stereotactic core needle biopsy is a simple procedure that may be performed in an outpatient imaging center.
  • Compared with open surgical biopsy, the procedure is about one-third the cost.
  • Generally, the procedure is not painful and the results are as accurate as when a tissue sample is removed surgically.
  • No breast defect remains and, unlike surgery, stereotactic needle biopsy does not distort the breast tissue and make it difficult to read future mammograms.
  • Recovery time is brief and patients can soon resume their usual activities.
  • No radiation remains in a patient's body after an x-ray examination.
  • X-rays usually have no side effects in the diagnostic range.

Risks

  • Because the vacuum-assisted device removes slightly larger pieces of tissue than other types of needles, there is a risk of bleeding and forming a hematoma, or a collection of blood at the biopsy site. The risk, however, appears to be less than one percent of patients.
  • An occasional patient has significant discomfort, which can be readily controlled by non-prescription pain medication.
  • Any procedure where the skin is penetrated carries a risk of infection. The chance of infection requiring antibiotic treatment appears to be less than one in 1,000.
  • Doing a biopsy of tissue located deep within the breast carries a slight risk that the needle will pass through the chest wall, allowing air around the lung that could collapse a lung. This is a rare occurrence.
  • There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk.
  • Women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant. See the Safety page (www.RadiologyInfo.org/en/safety/) for more information about pregnancy and x-rays.

What are the limitations of Stereotactic Breast Biopsy?

Lesions accompanied by diffuse calcium deposits scattered throughout the breast are difficult to target by stereotactic breast biopsy. Lesions near the chest wall also are hard to evaluate by this method. If the mammogram shows only a vague change in tissue density but no definite mass or nodule, this method may not be successful.
Breast biopsy procedures will occasionally miss a lesion or underestimate the extent of disease present. If the diagnosis remains uncertain after a technically successful procedure, surgical biopsy will usually be necessary.

Mammography

Play Video Clip (00:02:30)
Video: Your Radiologist Explains Mammography
Your Radiologist Explains 
Mammography

What is Mammography?

Mammography is a specific type of imaging that uses a low-dose x-ray system to examine breasts. A mammography exam, called a mammogram, is used to aid in the early detection and diagnosis of breast diseases in women.
An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
Two recent advances in mammography include digital mammography and computer-aided detection.
Digital mammography, also called full-field digital mammography (FFDM), is a mammography system in which the x-ray film is replaced by solid-state detectors that convert x-rays into electrical signals. These detectors are similar to those found in digital cameras. The electrical signals are used to produce images of the breast that can be seen on a computer screen or printed on special film similar to conventional mammograms. From the patient's point of view, having a digital mammogram is essentially the same as having a conventional film screen mammogram.
Computer-aided detection (CAD) systems use a digitized mammographic image that can be obtained from either a conventional film mammogram or a digitally acquired mammogram. The computer software then searches for abnormal areas of density, mass, or calcification that may indicate the presence of cancer. The CAD system highlights these areas on the images, alerting the radiologist to the need for further analysis.

What are some common uses of the procedure?

Mammograms are used as a screening tool to detect early breast cancer in women experiencing no symptoms and to detect and diagnose breast disease in women experiencing symptoms such as a lump, pain or nipple discharge.
Screening Mammography
Mammography plays a central part in early detection of breast cancers because it can show changes in the breast up to two years before a patient or physician can feel them. Current guidelines from the U.S. Department of Health and Human Services (HHS), the American Cancer Society (ACS), the American Medical Association (AMA) and the American College of Radiology (ACR) recommend screening mammography every year for women, beginning at age 40. Research has shown that annual mammograms lead to early detection of breast cancers, when they are most curable and breast-conservation therapies are available.
The National Cancer Institute (NCI) adds that women who have had breast cancer and those who are at increased risk due to a genetic history of breast cancer should seek expert medical advice about whether they should begin screening before age 40 and about the frequency of screening.
See the Breast Cancer page (www.RadiologyInfo.org/en/info.cfm?pg=breastcancer) for information about breast cancer therapy.
Diagnostic Mammography
Diagnostic mammography is used to evaluate a patient with abnormal clinical findings—such as a breast lump or lumps—that have been found by the woman or her doctor. Diagnostic mammography may also be done after an abnormal screening mammography in order to evaluate the area of concern on the screening exam.

How should I prepare?

Before scheduling a mammogram, the American Cancer Society (ACS) and other specialty organizations recommend that you discuss any new findings or problems in your breasts with your doctor. In addition, inform your doctor of any prior surgeries,hormone use, and family or personal history of breast cancer.
Do not schedule your mammogram for the week before your period if your breasts are usually tender during this time. The best time for a mammogram is one week following your period. Always inform your doctor or x-ray technologist if there is any possibility that you are pregnant.
The ACS also recommends you:
  • Do not wear deodorant, talcum powder or lotion under your arms or on your breasts on the day of the exam. These can appear on the mammogram as calcium spots.
  • Describe any breast symptoms or problems to the technologist performing the exam.
  • If possible, obtain prior mammograms and make them available to the radiologist at the time of the current exam.
  • Ask when your results will be available; do not assume the results are normal if you do not hear from your doctor or the mammography facility.

What does the equipment look like?

A mammography unit is a rectangular box that houses the tube in which x-rays are produced. The unit is used exclusively for x-ray exams of the breast, with special accessories that allow only the breast to be exposed to the x-rays. Attached to the unit is a device that holds and compresses the breast and positions it so images can be obtained at different angles.

How does the procedure work?

X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. Once it is carefully aimed at the part of the body being examined, an x-ray machine produces a small burst of radiation that passes through the body, recording an image on photographic film or a special digital image recording plate.
Different parts of the body absorb the x-rays in varying degrees. Dense bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray and air appears black.
Until recently, x-ray images were maintained as hard film copy (much like a photographic negative). Today, most images are digital files that are stored electronically. These stored images are easily accessible and are frequently compared to current x-ray images for diagnosis and disease management.

How is the procedure performed?

Mammography is performed on an outpatient basis.
During mammography, a specially qualified radiologic technologist will position your breast in the mammography unit. Your breast will be placed on a special platform and compressed with a paddle (often made of clear Plexiglas or other plastic). The technologist will gradually compress your breast.
Breast compression is necessary in order to:
  • Even out the breast thickness so that all of the tissue can be visualized.
  • Spread out the tissue so that small abnormalities are less likely to be obscured by overlying breast tissue.
  • Allow the use of a lower x-ray dose since a thinner amount of breast tissue is being imaged.
  • Hold the breast still in order to minimize blurring of the image caused by motion.
  • Reduce x-ray scatter to increase sharpness of picture.
You will be asked to change positions between images. The routine views are a top-to-bottom view and an oblique side view. The process will be repeated for the other breast.
You must hold very still and may be asked to keep from breathing for a few seconds while the x-ray picture is taken to reduce the possibility of a blurred image. Thetechnologist will walk behind a wall or into the next room to activate the x-ray machine.
When the examination is complete, you will be asked to wait until the radiologist determines that all the necessary images have been obtained.
The examination process should take about 30 minutes.

What will I experience during and after the procedure?

You will feel pressure on your breast as it is squeezed by the compression paddle. Some women with sensitive breasts may experience discomfort. If this is the case, schedule the procedure when your breasts are least tender. Be sure to inform the technologist if pain occurs as compression is increased. If discomfort is significant, less compression will be used.

Who interprets the results and how do I get them?

A radiologist, a physician specifically trained to supervise and interpret radiology examinations, will analyze the images and send a signed report to your primary care orreferring physician, who will discuss the results with you.
You will also be notified of the results by the mammography facility.

What are the benefits vs. risks?

Benefits

  • Imaging of the breast improves a physician's ability to detect small tumors. When cancers are small, the woman has more treatment options and a cure is more likely.
  • The use of screening mammography increases the detection of small abnormal tissue growths confined to the milk ducts in the breast, called ductal carcinoma in situ (DCIS). These early tumors cannot harm patients if they are removed at this stage and mammography is the only proven method to reliably detect these tumors. It is also useful for detecting all types of breast cancer, including invasive ductal and invasive lobular cancer.
  • No radiation remains in a patient's body after an x-ray examination.
  • X-rays usually have no side effects in the diagnostic range.

Risks

  • There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk.
  • The effective radiation dose from a mammogram is about 0.7 mSv, which is about the same as the average person receives from background radiation in three months. Federal mammography guidelines require that each unit be checked by a medical physicist every year to ensure that the unit operates correctly. See the Safety page (www.RadiologyInfo.org/en/safety/) for more information about radiation dose.
  • False Positive Mammograms. Five percent to 15 percent of screening mammograms require more testing such as additional mammograms orultrasound. Most of these tests turn out to be normal. If there is an abnormal finding, a follow-up or biopsy may have to be performed. Most of the biopsies confirm that no cancer was present. It is estimated that a woman who has yearly mammograms between ages 40 and 49 has about a 30 percent chance of having a false-positive mammogram at some point in that decade and about a 7 percent to 8 percent chance of having a breast biopsy within the 10-year period.
  • Women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant. See the Safety page (www.RadiologyInfo.org/en/safety/) for more information about pregnancy and x-rays.

A Word About Minimizing Radiation Exposure

Special care is taken during x-ray examinations to use the lowest radiation dose possible while producing the best images for evaluation. National and international radiology protection councils continually review and update the technique standards used by radiology professionals.
State-of-the-art x-ray systems have tightly controlled x-ray beams with significant filtration and dose control methods to minimize stray or scatter radiation. This ensures that those parts of a patient's body not being imaged receive minimal radiation exposure.

What are the limitations of Mammography?

Initial mammographic images themselves are not usually enough to determine the existence of a benign or malignant disease with certainty. If a finding or spot seems suspicious, your radiologist may recommend further diagnostic studies.
Interpretations of mammograms can be difficult because a normal breast can appear differently for each woman. Also, the appearance of an image may be compromised if there is powder or salve on the breasts or if you have undergone breast surgery. Because some breast cancers are hard to visualize, a radiologist may want to compare the image to views from previous examinations. Not all cancers of the breast can be seen on mammography.
Breast implants can also impede accurate mammogram readings because both silicone and saline implants are not transparent on x-rays and can block a clear view of the tissues behind them, especially if the implant has been placed in front of, rather than beneath, the chest muscles Experienced technologists and radiologists know how to carefully compress the breasts to improve the view without rupturing the implant.
When making an appointment for a mammogram, women with implants should ask if the facility uses special techniques designed to accommodate them. Before the mammogram is taken, they should make sure the technologist is experienced in performing mammography on patients with breast implants.
While mammography is the best screening tool for breast cancer available today, mammograms do not detect all breast cancers. Also, a small portion of mammograms indicate that a cancer could possibly be present when it is not (called a false-positive result).
Research is being done on a variety of breast imaging techniques that can contribute to the early detection of breast cancer and improve the accuracy in distinguishing non-cancerous breast conditions from breast cancers.

Normal mammogram
Normal mammogram

Mammography

Computer-aided detection (CAD) mammogram
Computer-aided detection (CAD) mammogram


No comments:

Post a Comment