Title of Invention	SUBCUTANEOUS BIOPSY CAVITY MARKER DEVICE
Abstract	The invention relates to a marking device for identifying a subcutaneous biopsy cavity comprising a first nonabsorbable marker element detectable by a first imaging modality; and a second marker element detectable by a second imaging modality but not detectable by said first imaging modality, wherein the second marker element extends generally along an axis and the first marker element is radiopaque, encircles a portion of the second marker element, and lies in a plane that is generally perpendicular to the axis of the second marker element.

Title of Invention

SUBCUTANEOUS BIOPSY CAVITY MARKER DEVICE

Abstract

The invention relates to a marking device for identifying a subcutaneous biopsy cavity comprising a first nonabsorbable marker element detectable by a first imaging modality; and a second marker element detectable by a second imaging modality but not detectable by said first imaging modality, wherein the second marker element extends generally along an axis and the first marker element is radiopaque, encircles a portion of the second marker element, and lies in a plane that is generally perpendicular to the axis of the second marker element.

Full Text	SUBCUTANEOUS BIOPSY CAVITY MARKER DEVICE Field of the Invention This application claims priority to U.S. Provisional App. Serial No. 60/476,533 filed June 6, 2003, the contents of which are hereby incorporated by reference. This invention relates to nonabsorbablebiopsy cavity maker devices and methods for identifying such devices in a subcutaneous biopsy cavity, including a breast biopsy cavity. Background of the Invention Invasive breast cancer, the most common nonskin cancer in American women, was disgnosed in approximately 184,000 women in the United States in 2000, and let to approximately 41,000 deaths (Nancy E. Davidson. 2001. "Breast Cancer", Section 12 Part VII In Scientific American Medicine. Edward Rubenstein and Daniel D. Fedennan eds., Scientific American, Inc.: New York, NY). Current guidelines for breast cancer screening recommended by the American Cancer Society and the National Cancer Institute include monthly breast self examination for all women older than 20 years and annual mammography for women older than 40 years who are at standard risk for breast cancer. For those at higher risk, current practice advocates that mammographic screening begin at 25 years of age or five years earlier than the age of the person with the earliest diagnosis of breast cancer in the immediate or extended family. Breast cancer may present as architectural changes or microcalcifications on a mammogram, or by clinical symptoms, such as a palpable mass, nipple discharge, or skin or nipple changes. Regardless of whether the patient is symptomatic or asymptomatic, a histologic examination of the suspect tissue is mandatory to establish a diagnosis. Open incisional or excisional biopsies were commonly performed in the past to obtain tissue samples. The modern trend relies on fine-needle aspiration, core-needle biopsy, or other image guided or non-image guided percutaneous procedures, e.g., vacuum assisted biopsy using the MAMMOTOME® breast biopsy system (Ethicon Endo-Surgery, Inc., Cincinnati, OH), to obtain a sample of cells or tissue for diagnosis. After any given biopsy procedure, a subsequent examination of the biopsy site is often desirable. For example, if the initial biopsy only partially removed the suspect tissue, and a malignant lesion is subsequently diagnosed, re-excision of the original biopsy site is indicated. Identification of a biopsy site is also helpful during patient follow-up examinations for reoccurrence. Thus, mere is a need to determine the location, most importantly the center, as well as the orientation and margins of the subcutaneous tissue cavity from which the suspect lesion is removed. Prior methods of marking biopsy cavities utilize one or more tissue marking clips as the biopsy site marking device. One representative marking apparatus is the MICROMARK™II tissue marker (Biopsis Medical, Inc., Irvine, CA). Among other concerns, deployment of the MICROMARK™]] tissue maker is unreliable, the marker device often failing to properly attach to the cavity wall. Furthermore, because clip attachment occurs to the side, not the center of the cavity, spatial orientation and position of the cavity is difficult if not impossible during follow-up examination. Moreover, during the stereotactic breast biopsy procedure, the breast is under compression when the marking clip is placed. Upon release of the compressive force, the clip will migrate relative to the biopsy void, and the orientation as well as the location of the margins of the cavity are usually lost. Other biopsy markers that attempt to minimize migration, e.g., after tissue is decompressed, are described in U.S. 6,161,034 and U.S. 6,347,241, both to Burbank et al.; U.S. 6,270,464 to Fulton, III et al.; and U.S. 6,350,244 and WO 01/62135, both to Fisher. Burbank et al. describes chemical preparations of collagen or gelatin having a visible marker such as carbon particles or a dye that are introduced into biopsy cavities. The markers are imageable by mammography, fluoroscopy, CT, or MRI. Fulton, m et al. depicts a swellable marker that may be palpably harder after delivery into the biopsy cavity. The marker is imageable by mammography, ultrasound, or MRI. In U.S. 6,350,244 and WO 01/62135, Fisher describes markers that are hollow spheres made from polylactic acid. The spheres are filled with iodine or other radiopaque material to make mem imageable by available radiograpbic techniques such as x-ray and/or ultrasound. Multiple markers are introduced to fill the biopsy cavity. In U.S. 6,347,241, Burbank et al. describes a marker body mat includes a pre- shaped pellet formed of bioabsorbable material having a plurality of gas bubbles dispersed therein which are configured to facilitate ultrasonic observation of the pellet at a biopsy site within a patient and having an X-ray detectable element of specific predetermined non-biological configuration embedded therein. Although the above mentioned marker devices address some of the problems associated with clip-type markers, the problem of prolonged monitoring of a biopsy site still remains. Thus, it would be of considerable medical benefit to be able to permanently mark the location of a biopsy cavity, especially after a percutaneous biopsy procedure. Summary of the Invention The present invention is a subcutaneous biopsy cavity marking device that permanently remains within the biopsy cavity after deployment, and which has one or more marker elements mat allows identification of the biopsy cavity center, orientation, or margin, using various imaging modalities. The marking device generally includes a first marker element and a second nonabsorbable marker element. The first marker element is detectable by a first imaging modality. The second marker element is detectable by a second imaging modality that differs from the first imaging modality. In one embodiment, the first imaging modality usually does not visualize the second marker element. However, if it is visualized, the second marker element will have a configuration such that it is distinguishable from naturally occurring artifacts, and is configured so that it does not obscure the presence of any tissue pathology or confound the reading of any imaging study using the first modality. In a preferred variation, x-ray is the first imaging modality and ultrasonography is the second imaging modality. The first marker element may be variously shaped, and made from materials such as gold, iridium, nickel, rhodium, silver, stainless steel, tantalum, titanium, and alloys thereof. A radiopaque additive may also be coated on or incorporated into the first marker element to enhance the radiopacity of the element. The second marker element may also have various configurations asd is formed from nonabsorbable materials such as fluoropolymers, polyester or polyester mixtures, polypropylene, and nylon or nylon mixtures. An echogenic coating may also be provided on the second marker element to enhance its detection by ultrasound imaging. In addition to being nonabsorbable, in one embodiment of the invention, the marking devices are nonpalpable. In a further embodiment, pharmaceutical agents such as hemostatic, analgesic, or anesthetic substances may also be incorporated into either the first or second marker elements or both. In some cases, it may also be desirable to form the marker device to emit therapeutic radiation to treat any diseased tissue remaining within the biopsy cavity. Brief Description of the Figures Figures 1A-1G illustrate various configurations of the biopsy cavity markerA devices. Figure 1A shows a spherical biopsy cavity marker device according to one variation of the invention. Figure 1B shows a multi-faced biopsy cavity marker device according to another variation of the invention. Figure 1C shows a cylindrical biopsy cavity marker device according to another variation of the invention. Figure 1D shows a knotted suture biopsy cavity marker device according to yet another variation of the invention. Figure 1E is a biopsy cavity marker device having a looped arrangement according to another variation of the invention. Figure 1F is a biopsy cavity marker having a layered configuration according to another variation of the invention. Figure 1G is a biopsy cavity marker having a rolled configuration according to another variation of the invention. Figure 2A shows a first marker element having a ring shape according to one variation of the invention. Figure 2B shows a first marker element having a barbed ('V) shape according to another variation of the invention. Figure 2C shows a first marker element having a plurality of ring-shaped components connected by a joining element according to another aspect of the invention. Detailed Description of the Invention The biopsy marker devices of this invention may take various forms, but are generally configured to have a size and shape appropriate for identifying a biopsy cavity, e.g., a breast biopsy cavity. Once within the biopsy cavity, the marker device allows localization, as well as orientation and identification of the cavity margins. The marker devices are nonabsorbable, allowing long-term follow-up examination of the biopsy site if desired. When the marker devices permanently remain within the biopsy cavities, they are preferably formed to be nonpalpable. The reluctance to use nonabsorbable biopsy cavity markers may arise from the notion that a foreign body reaction may be generated by the prolonged presence of the marker in the cavity, leading to flbrosis. The area of induration would most likely be palpable and thus, undesirable to the patient. Therefore, the marker devices of this invention will be constructed from biocompatible materials which do not produce any detrimental effect (such as fibrosis or other palpable or noticeable condition) on the patient. Furthermore, a need for nonabsorbable markers was not present in the past because most patients with nonpalpable suspicious lesions underwent wire localization . biopsy which is an open incisional or excisional biopsy. If a malignancy was diagnosed from the specimen, re-excision was accomplished by opening the previous incision. However, with the increasing popularity of percutaneous biopsy procedures and breast- sparing surgery, biopsy cavities are decreasing in size, making them difficult to detect on follow-up imaging. Long-term follow-up for suspicious lesions that are found to be benign after percutaneous biopsy is difficult if biopsy cavity markers are generally bioabsorbable, and degrade after a few months. The biopsy cavity markers of this invention are nonabsorbable, and thus are detectable for follow-up over any desired period of time. The marker devices may be introduced into biopsy cavities by various suitable percutaneous access devices, e.g., as described in U.S. 6,356,782 and U.S. 6,371,904 to Sirimanne et al., and U.S. Publication No. 2003/0050571 to Zarins et al which are herein incorporate by reference in their entireties. Figures 1A-1G show various configurations of subcutaneous cavity marking devices of the present invention. In the Figures, the marker device 100 is displayed as having either a generally spherical body (Fig. 1A), a multi-faced body 106 (Fig. IB), or a generally cylindrical body 112 (Fig. 1C). In addition, it is within the scope of this invention for the body to assume a variety of other shapes. For example, the marker device may be configured to have conical or ellipsoidal shapes, substantially planar surfaces, such as polyhedric (i.e., cubic, tetrahedral) or prismatic forms, and the like. Furthermore, the nonabsorbable materials that make up the marker devices may be designed to have a knotted structure (Fig. ID) or a looped (Fig E), layered (Fig. IF), or rolled (Fig. 1G) arrangement. The particular marker device may be of any shape, as well as size, so long as the marker is distinguishable from tissue pathology, e.g., microcalcifications, or from anatomically occurring artifacts, and will typically be chosen to best match die biopsy cavity dimensions. Marker devices having a fixed geometry, e.g., rolls or cubes, are preferable because their geometry is more readily distinguishable from tissue pathology and anatomically occurring artifacts. The subcutaneous biopsy cavity markers generally include a first marker element (e.g., 102, 108, 114, 118, 122,126, 130) and a second marker element (e.g., 104,110, 116,120, 124, 128,132). The first marker element is detectable by a first imaging modality. The second marker element is detectable by a second imaging modality but preferably is not detectable by the first imaging modality. By "not detectable" we mean that under the first imaging modality there is no significant visualization of the second marker element. The second imaging modality will typically provide a more efficient outpatient follow-up process because the imaging device is portable, and readily available in most surgical oncology offices. Preferably, the first imaging modality is x-ray and the second imaging modality is ultrasonography. The first imaging modality is usually a radiographic imaging modality. For example, an x-ray such as a mammogram may be taken, or an image may be obtained using computed tomography (CT) for fluoroscopy. Besides radiography, magnetic resonance imaging (MRI) may also be performed. In a preferred variation, mammography is used as the first imaging modality. By using ultrasonography as the second imaging modality, which will also be employed for long-term follow-up, total radiation exposure to the patient is decreased. In addition, the increasing use of hand-held or portable ultrasound devices by surgeons provides convenient long-term outpatient follow-up without referral back to a radiologist. The first marker element 102,108,114,118, 122, 126, 130 may be confined within the structure of the second marker element 104, 110, 116, 120, 124, 128,132, as seen in Figs. 1A-1C, or may wrap around a portion of the second marker element, as seen in Figs. 1D-1G. The placement of the marker elements in relation to one another may vary according to such factors as type of tissue biopsied, dimensions of the biopsy cavity, number of first marker elements employed, and physician preference, so long as the center of the cavity, and the orientation and margins of the cavity can generally be identified. The first marker element 102,108,114,118,122, 126,130 may be spherical (Figs. 1A and IB), ring-shaped (Figs. 1C-1G, 2A), or barbed in a V configuration (Fig. 2B). Although the Figures illustrate only three configurations for the first marker elements, the invention contemplates other configurations that allow adequate detection of the biopsy cavity as described above. Furthermore, a plurality of first marker elements may be included in the marking device if so indicated or desired. In one variation, as seen in Figure 2C, a plurality of rings 200 are connected by a joining member 204, e.g., by an adhesive or soldering, to form a first marker element 206. In one embodiment, the first marker element 102,108, 114, 118, 122, 126,130 may be made from nonabsorbable, metallic materials including, but not limited to, gold; iridium; nickel; rhodium; silver; stainless steel; tantalum; titanium; and alloys thereof. In a preferred variation, the first marker element is made from titanium. However, the first marker element may be made from any type of materials, so long as it is biocompatible and nonabsorbable. If desired, the radiopaciry of the first marker element may be enhanced by adding a radiopaque additive coating to the marker. Suitable radiopaque additives include elements such as barium-containing compounds, bismuth- containing compounds, powdered tantalum, powdered tungsten, barium carbonate, bismuth oxide, and barium sulfate. The second marker element may also be provided in various configurations. For example, in one variation, the second marker element 120 is formed from knotted surgical suture. As seen in Fig. ID, the first marker element 118 is a ring that wraps around the second marker element 120 in the form of a knotted mass.. In another variation, the second marker element is a looped arrangement of suture 124 (Fig. IE). The suture material is looped through the first marker element 122, also a ring structure, to form a pair of opposing loops 125. In yet a further variation, the second marker element is a layered arrangement of nonabsorbable, echogenic, sheet or mesh-like material 128 centrally fastened together with a ring-shaped first marker element 126 (Fig. IF). In another variation, as seen in Fig 1G, the second marker element is in a rolled configuration 132. The roll 132 is passed through and secured by a first marker element, ring 130. In some instances, a plurality of second marker elements may be deployed to fill the biopsy cavity. The second marker element may be made from biocompatdble, nonabsorbable materials including, but not limited to, polymers such as fluoropolymers; polyester (e.g., Reemay® spunbond polyester, Dacron® polyester fibers) and polyester mixtures (e.g., mixtures of polyester and rayon); polypropylene; and nylon and nylon mixtures. If desired, the second marker element may be made from a resilient material. The composition of the second marker element may vary so long as the material it is made from is biocompatible, nonabsorbable, detectable by ultrasound (echogenic), and nonpalpable when placed into a biopsy cavity. These nonabsorbable materials may be subjected to processes such as lyophilization or sintering to bulk them and/or have them capture air. Die-cut second marker elements may be produced using materials treated in this matter. For example, instead of layering or rolling the nonabsorbable material as shown in Figs. IF an 1G, respectively, a structure that resembles the shape and size of the layered or rolled marker elements may be cut out from nonabsorbable material that has been lyophilized. To enhance detection by ultrasound, the second marker element may be coated with an echogenic substance. One such substance is the ECHO-COAT® coating (STS Biopolymers, Henrietta, NY). Echogenic coatings provide the coated marker element with an acoustically reflective interface and a large acoustical impedence differential. Pharmaceutical agents such as hemostatic, analgesic, or anesthetic agents may also be incorporated into the first and/or second marker elements of the device. Hemostasis-promoting agents help to prevent the formation of hematomas and may also help to promote the healing process. The first and/or second marker elements of the biopsy cavity marker device may also be formed to emit therapeutic radiation to treat any cancerous tissue remaining in the margin of the biopsy cavity. The biopsy cavity marker devices of the present invention may be inserted into a biopsy cavity by any known means. For example, a marker (or several markers) may be inserted into a syringe type applicator and injected into a biopsy cavity. All publications, patents, and patent applications cited herein are hereby incorporated by reference in their entirety for all purposes to the same extent as if each individual publication, patent, or patent application were specifically and individually indicated to be so incorporated by reference. Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto without departing from the spirit and scope of the appended claims. WHAT IS CLAIMED IS: WE CLAIM 1. A marking device for identifying a subcutaneous biopsy cavity comprising: a first nonabsorbable marker element detectable by a first imaging modality; and a second marker element detectable by a second imaging modality but not detectable by said first imaging modality, wherein the second marker element extends generally along an axis and the first marker element is radiopaque, encircles a portion of the second marker element, and lies in a plane that is generally perpendicular to the axis of the second marker element. 2. The marking device as claimed in claim 1 wherein said device is nonpalpable. 3. The marking device as claimed in claim 1 wherein said first marker element comprises a material selected from a group consisting of gold; iridium; nickel; silver; stainless steel; tantalum; titanium; and alloys thereof. 4. The marking device as claimed in claim 1 wherein said first marker element comprises titanium. 5. The marking device as claimed in claim 1 wherein said first marker element comprises a radiopaque additive. 6. The marking device as claimed in claim 5 wherein said radiopaque additive is selected from the group consisting of barium-containing compounds, bismuth-containing compounds, powdered tantalum, powdered tungsten, barium carbonate, bismuth oxide, and barium sulfate. 7. The marking device as claimed in claim 1 wherein said first marker element is spherical. 8. The marking device as claimed in claim 1 wherein said first marker element is ring-shaped. 9. The marking device as claimed in claim 1 wherein said first marker element has a V-shaped configuration. 10.The marking device as claimed in claim 1 wherein said first imaging modality is a radiographic imaging modality. 11.The marking device as claimed in claim 10 wherein said radiographic imaging modality is an x-ray. 12.The marking device as claimed in claim 11 wherein said x-ray is a mammogram. 13.The marking device as claimed in claim 1 wherein said first imaging modality is mammography. 14.The marking device as claimed in claim 1 wherein said second marker element comprises a material selected from the group consisting of fluoropolymers, polyester and polyester mixtures, polypropylene, and nylon and nylon mixtures. 15.The marking device as claimed in claim 1 wherein said second marker element comprises an echogenic coating. 16.The marking device as claimed in claim 1 wherein said second marker element comprises a knotted suture. 17.The marking device as claimed in claim 1 wherein said second marker element comprises a looped arrangement of suture. 18.The marking device as claimed in claim 1 wherein said second marker element comprises a layered arrangement of sheet or mesh-like material. 19.The marking device as claimed in claim 1 wherein said second marker element has a rolled configuration. 20.The marking device as claimed in claim 1 wherein said second marker element has a geometry distinguishable from an anatomically occurring artifact or tissue pathology. 21.The marking device as claimed in claim 1 wherein said second imaging modality is ultrasonography. 22.The marking device as claimed in claim 1 wherein said first imaging modality is x-ray and said second imaging modality is ultrasonography. 23.The marking device as claimed in claim 1 wherein said second nonabsorbable marker element is resilient. 24.The marking device as claimed in claim 1 wherein said first marker element comprises a metal and said second nonabsorbable marker element comprises a polymer. The invention relates to a marking device for identifying a subcutaneous biopsy cavity comprising a first nonabsorbable marker element detectable by a first imaging modality; and a second marker element detectable by a second imaging modality but not detectable by said first imaging modality, wherein the second marker element extends generally along an axis and the first marker element is radiopaque, encircles a portion of the second marker element, and lies in a plane that is generally perpendicular to the axis of the second marker element.

Full Text

SUBCUTANEOUS BIOPSY CAVITY MARKER DEVICE
Field of the Invention
This application claims priority to U.S. Provisional App. Serial No. 60/476,533
filed June 6, 2003, the contents of which are hereby incorporated by reference. This
invention relates to nonabsorbablebiopsy cavity maker devices and methods for
identifying such devices in a subcutaneous biopsy cavity, including a breast biopsy
cavity.
Background of the Invention
Invasive breast cancer, the most common nonskin cancer in American women,
was disgnosed in approximately 184,000 women in the United States in 2000, and let to
approximately 41,000 deaths (Nancy E. Davidson. 2001. "Breast Cancer", Section 12 Part
VII In Scientific American Medicine. Edward Rubenstein and Daniel D. Fedennan eds.,
Scientific American, Inc.: New York, NY). Current guidelines for breast cancer
screening recommended by the American Cancer Society and the National Cancer
Institute include monthly breast self examination for all women older than 20 years and
annual mammography for women older than 40 years who are at standard risk for breast
cancer. For those at higher risk, current practice advocates that mammographic screening
begin at 25 years of age or five years earlier than the age of the person with the earliest
diagnosis of breast cancer in the immediate or extended family.
Breast cancer may present as architectural changes or microcalcifications on a
mammogram, or by clinical symptoms, such as a palpable mass, nipple discharge, or skin
or nipple changes. Regardless of whether the patient is symptomatic or asymptomatic, a
histologic examination of the suspect tissue is mandatory to establish a diagnosis. Open
incisional or excisional biopsies were commonly performed in the past to obtain tissue
samples. The modern trend relies on fine-needle aspiration, core-needle biopsy, or other
image guided or non-image guided percutaneous procedures, e.g., vacuum assisted biopsy
using the MAMMOTOME® breast biopsy system (Ethicon Endo-Surgery, Inc.,
Cincinnati, OH), to obtain a sample of cells or tissue for diagnosis.
After any given biopsy procedure, a subsequent examination of the biopsy site is
often desirable. For example, if the initial biopsy only partially removed the suspect
tissue, and a malignant lesion is subsequently diagnosed, re-excision of the original
biopsy site is indicated. Identification of a biopsy site is also helpful during patient
follow-up examinations for reoccurrence. Thus, mere is a need to determine the location,
most importantly the center, as well as the orientation and margins of the subcutaneous
tissue cavity from which the suspect lesion is removed.
Prior methods of marking biopsy cavities utilize one or more tissue marking clips
as the biopsy site marking device. One representative marking apparatus is the
MICROMARK™II tissue marker (Biopsis Medical, Inc., Irvine, CA). Among other
concerns, deployment of the MICROMARK™]] tissue maker is unreliable, the marker
device often failing to properly attach to the cavity wall. Furthermore, because clip
attachment occurs to the side, not the center of the cavity, spatial orientation and position
of the cavity is difficult if not impossible during follow-up examination. Moreover,
during the stereotactic breast biopsy procedure, the breast is under compression when the
marking clip is placed. Upon release of the compressive force, the clip will migrate
relative to the biopsy void, and the orientation as well as the location of the margins of the
cavity are usually lost.
Other biopsy markers that attempt to minimize migration, e.g., after tissue is
decompressed, are described in U.S. 6,161,034 and U.S. 6,347,241, both to Burbank et
al.; U.S. 6,270,464 to Fulton, III et al.; and U.S. 6,350,244 and WO 01/62135, both to
Fisher.
Burbank et al. describes chemical preparations of collagen or gelatin having a
visible marker such as carbon particles or a dye that are introduced into biopsy cavities.
The markers are imageable by mammography, fluoroscopy, CT, or MRI.
Fulton, m et al. depicts a swellable marker that may be palpably harder after
delivery into the biopsy cavity. The marker is imageable by mammography, ultrasound,
or MRI.
In U.S. 6,350,244 and WO 01/62135, Fisher describes markers that are hollow
spheres made from polylactic acid. The spheres are filled with iodine or other radiopaque
material to make mem imageable by available radiograpbic techniques such as x-ray
and/or ultrasound. Multiple markers are introduced to fill the biopsy cavity.
In U.S. 6,347,241, Burbank et al. describes a marker body mat includes a pre-
shaped pellet formed of bioabsorbable material having a plurality of gas bubbles
dispersed therein which are configured to facilitate ultrasonic observation of the pellet at
a biopsy site within a patient and having an X-ray detectable element of specific
predetermined non-biological configuration embedded therein.
Although the above mentioned marker devices address some of the problems
associated with clip-type markers, the problem of prolonged monitoring of a biopsy site
still remains. Thus, it would be of considerable medical benefit to be able to permanently
mark the location of a biopsy cavity, especially after a percutaneous biopsy procedure.
Summary of the Invention
The present invention is a subcutaneous biopsy cavity marking device that
permanently remains within the biopsy cavity after deployment, and which has
one or more marker elements mat allows identification of the biopsy cavity center,
orientation, or margin, using various imaging modalities.
The marking device generally includes a first marker element and a second
nonabsorbable marker element. The first marker element is detectable by a first imaging
modality. The second marker element is detectable by a second imaging modality that
differs from the first imaging modality. In one embodiment, the first imaging modality
usually does not visualize the second marker element. However, if it is visualized, the
second marker element will have a configuration such that it is distinguishable from
naturally occurring artifacts, and is configured so that it does not obscure the presence of
any tissue pathology or confound the reading of any imaging study using the first
modality. In a preferred variation, x-ray is the first imaging modality and
ultrasonography is the second imaging modality.
The first marker element may be variously shaped, and made from materials such
as gold, iridium, nickel, rhodium, silver, stainless steel, tantalum, titanium, and alloys
thereof. A radiopaque additive may also be coated on or incorporated into the first
marker element to enhance the radiopacity of the element.
The second marker element may also have various configurations asd is formed
from nonabsorbable materials such as fluoropolymers, polyester or polyester mixtures,
polypropylene, and nylon or nylon mixtures. An echogenic coating may also be provided
on the second marker element to enhance its detection by ultrasound imaging.
In addition to being nonabsorbable, in one embodiment of the invention, the
marking devices are nonpalpable. In a further embodiment, pharmaceutical agents such
as hemostatic, analgesic, or anesthetic substances may also be incorporated into either the
first or second marker elements or both. In some cases, it may also be desirable to form
the marker device to emit therapeutic radiation to treat any diseased tissue remaining
within the biopsy cavity.
Brief Description of the Figures
Figures 1A-1G illustrate various configurations of the biopsy cavity markerA
devices.
Figure 1A shows a spherical biopsy cavity marker device according to one
variation of the invention.
Figure 1B shows a multi-faced biopsy cavity marker device according to another
variation of the invention.
Figure 1C shows a cylindrical biopsy cavity marker device according to another
variation of the invention.
Figure 1D shows a knotted suture biopsy cavity marker device according to yet
another variation of the invention.
Figure 1E is a biopsy cavity marker device having a looped arrangement
according to another variation of the invention.
Figure 1F is a biopsy cavity marker having a layered configuration according to
another variation of the invention.
Figure 1G is a biopsy cavity marker having a rolled configuration according to
another variation of the invention.
Figure 2A shows a first marker element having a ring shape according to one
variation of the invention.
Figure 2B shows a first marker element having a barbed ('V) shape according to
another variation of the invention.
Figure 2C shows a first marker element having a plurality of ring-shaped
components connected by a joining element according to another aspect of the invention.
Detailed Description of the Invention
The biopsy marker devices of this invention may take various forms, but are
generally configured to have a size and shape appropriate for identifying a biopsy cavity,
e.g., a breast biopsy cavity. Once within the biopsy cavity, the marker device allows
localization, as well as orientation and identification of the cavity margins. The marker
devices are nonabsorbable, allowing long-term follow-up examination of the biopsy site if
desired. When the marker devices permanently remain within the biopsy cavities, they
are preferably formed to be nonpalpable.
The reluctance to use nonabsorbable biopsy cavity markers may arise from the
notion that a foreign body reaction may be generated by the prolonged presence of the
marker in the cavity, leading to flbrosis. The area of induration would most likely be
palpable and thus, undesirable to the patient. Therefore, the marker devices of this
invention will be constructed from biocompatible materials which do not produce any
detrimental effect (such as fibrosis or other palpable or noticeable condition) on the
patient.
Furthermore, a need for nonabsorbable markers was not present in the past
because most patients with nonpalpable suspicious lesions underwent wire localization .
biopsy which is an open incisional or excisional biopsy. If a malignancy was diagnosed
from the specimen, re-excision was accomplished by opening the previous incision.
However, with the increasing popularity of percutaneous biopsy procedures and breast-
sparing surgery, biopsy cavities are decreasing in size, making them difficult to detect on
follow-up imaging. Long-term follow-up for suspicious lesions that are found to be
benign after percutaneous biopsy is difficult if biopsy cavity markers are generally
bioabsorbable, and degrade after a few months. The biopsy cavity markers of this
invention are nonabsorbable, and thus are detectable for follow-up over any desired
period of time.
The marker devices may be introduced into biopsy cavities by various suitable
percutaneous access devices, e.g., as described in U.S. 6,356,782 and U.S. 6,371,904 to
Sirimanne et al., and U.S. Publication No. 2003/0050571 to Zarins et al which are herein
incorporate by reference in their entireties.
Figures 1A-1G show various configurations of subcutaneous cavity marking
devices of the present invention. In the Figures, the marker device 100 is displayed as
having either a generally spherical body (Fig. 1A), a multi-faced body 106 (Fig. IB), or a
generally cylindrical body 112 (Fig. 1C). In addition, it is within the scope of this
invention for the body to assume a variety of other shapes. For example, the marker
device may be configured to have conical or ellipsoidal shapes, substantially planar
surfaces, such as polyhedric (i.e., cubic, tetrahedral) or prismatic forms, and the like.
Furthermore, the nonabsorbable materials that make up the marker devices may be
designed to have a knotted structure (Fig. ID) or a looped (Fig E), layered (Fig. IF), or
rolled (Fig. 1G) arrangement.
The particular marker device may be of any shape, as well as size, so long as the
marker is distinguishable from tissue pathology, e.g., microcalcifications, or from
anatomically occurring artifacts, and will typically be chosen to best match die biopsy
cavity dimensions. Marker devices having a fixed geometry, e.g., rolls or cubes, are
preferable because their geometry is more readily distinguishable from tissue pathology
and anatomically occurring artifacts.
The subcutaneous biopsy cavity markers generally include a first marker element
(e.g., 102, 108, 114, 118, 122,126, 130) and a second marker element (e.g., 104,110,
116,120, 124, 128,132). The first marker element is detectable by a first imaging
modality. The second marker element is detectable by a second imaging modality but
preferably is not detectable by the first imaging modality. By "not detectable" we mean
that under the first imaging modality there is no significant visualization of the second
marker element. The second imaging modality will typically provide a more efficient
outpatient follow-up process because the imaging device is portable, and readily available
in most surgical oncology offices. Preferably, the first imaging modality is x-ray and the
second imaging modality is ultrasonography.
The first imaging modality is usually a radiographic imaging modality. For
example, an x-ray such as a mammogram may be taken, or an image may be obtained
using computed tomography (CT) for fluoroscopy. Besides radiography, magnetic
resonance imaging (MRI) may also be performed. In a preferred variation,
mammography is used as the first imaging modality. By using ultrasonography as the
second imaging modality, which will also be employed for long-term follow-up, total
radiation exposure to the patient is decreased. In addition, the increasing use of hand-held
or portable ultrasound devices by surgeons provides convenient long-term outpatient
follow-up without referral back to a radiologist.
The first marker element 102,108,114,118, 122, 126, 130 may be confined
within the structure of the second marker element 104, 110, 116, 120, 124, 128,132, as
seen in Figs. 1A-1C, or may wrap around a portion of the second marker element, as seen
in Figs. 1D-1G. The placement of the marker elements in relation to one another may
vary according to such factors as type of tissue biopsied, dimensions of the biopsy cavity,
number of first marker elements employed, and physician preference, so long as the
center of the cavity, and the orientation and margins of the cavity can generally be
identified.
The first marker element 102,108,114,118,122, 126,130 may be spherical
(Figs. 1A and IB), ring-shaped (Figs. 1C-1G, 2A), or barbed in a V configuration (Fig.
2B). Although the Figures illustrate only three configurations for the first marker
elements, the invention contemplates other configurations that allow adequate detection
of the biopsy cavity as described above. Furthermore, a plurality of first marker elements
may be included in the marking device if so indicated or desired. In one variation, as
seen in Figure 2C, a plurality of rings 200 are connected by a joining member 204, e.g.,
by an adhesive or soldering, to form a first marker element 206.
In one embodiment, the first marker element 102,108, 114, 118, 122, 126,130
may be made from nonabsorbable, metallic materials including, but not limited to, gold;
iridium; nickel; rhodium; silver; stainless steel; tantalum; titanium; and alloys thereof. In
a preferred variation, the first marker element is made from titanium. However, the first
marker element may be made from any type of materials, so long as it is biocompatible
and nonabsorbable.
If desired, the radiopaciry of the first marker element may be enhanced by adding
a radiopaque additive coating to the marker. Suitable radiopaque additives include
elements such as barium-containing compounds, bismuth- containing compounds,
powdered tantalum, powdered tungsten, barium carbonate, bismuth oxide, and barium
sulfate.
The second marker element may also be provided in various configurations. For
example, in one variation, the second marker element 120 is formed from knotted surgical
suture. As seen in Fig. ID, the first marker element 118 is a ring that wraps around the
second marker element 120 in the form of a knotted mass.. In another variation, the
second marker element is a looped arrangement of suture 124 (Fig. IE). The suture
material is looped through the first marker element 122, also a ring structure, to form a
pair of opposing loops 125. In yet a further variation, the second marker element is a
layered arrangement of nonabsorbable, echogenic, sheet or mesh-like material 128
centrally fastened together with a ring-shaped first marker element 126 (Fig. IF). In
another variation, as seen in Fig 1G, the second marker element is in a rolled
configuration 132. The roll 132 is passed through and secured by a first marker element,
ring 130. In some instances, a plurality of second marker elements may be deployed to
fill the biopsy cavity.
The second marker element may be made from biocompatdble, nonabsorbable
materials including, but not limited to, polymers such as fluoropolymers; polyester (e.g.,
Reemay® spunbond polyester, Dacron® polyester fibers) and polyester mixtures (e.g.,
mixtures of polyester and rayon); polypropylene; and nylon and nylon mixtures. If
desired, the second marker element may be made from a resilient material. The
composition of the second marker element may vary so long as the material it is made
from is biocompatible, nonabsorbable, detectable by ultrasound (echogenic), and
nonpalpable when placed into a biopsy cavity. These nonabsorbable materials may be
subjected to processes such as lyophilization or sintering to bulk them and/or have them
capture air. Die-cut second marker elements may be produced using materials treated in
this matter. For example, instead of layering or rolling the nonabsorbable material as
shown in Figs. IF an 1G, respectively, a structure that resembles the shape and size of the
layered or rolled marker elements may be cut out from nonabsorbable material that has
been lyophilized.
To enhance detection by ultrasound, the second marker element may be coated
with an echogenic substance. One such substance is the ECHO-COAT® coating (STS
Biopolymers, Henrietta, NY). Echogenic coatings provide the coated marker element
with an acoustically reflective interface and a large acoustical impedence differential.
Pharmaceutical agents such as hemostatic, analgesic, or anesthetic agents may
also be incorporated into the first and/or second marker elements of the device.
Hemostasis-promoting agents help to prevent the formation of hematomas and may also
help to promote the healing process. The first and/or second marker elements of the
biopsy cavity marker device may also be formed to emit therapeutic radiation to treat any
cancerous tissue remaining in the margin of the biopsy cavity.
The biopsy cavity marker devices of the present invention may be inserted into a
biopsy cavity by any known means. For example, a marker (or several markers) may be
inserted into a syringe type applicator and injected into a biopsy cavity.
All publications, patents, and patent applications cited herein are hereby
incorporated by reference in their entirety for all purposes to the same extent as if each
individual publication, patent, or patent application were specifically and individually
indicated to be so incorporated by reference. Although the foregoing invention has been
described in some detail by way of illustration and example for purposes of clarity of
understanding, it will be readily apparent to those of ordinary skill in the art in light of the
teachings of this invention that certain changes and modifications may be made thereto
without departing from the spirit and scope of the appended claims.
WHAT IS CLAIMED IS:
WE CLAIM
1. A marking device for identifying a subcutaneous biopsy cavity comprising:
a first nonabsorbable marker element detectable by a first imaging
modality; and
a second marker element detectable by a second imaging modality but
not detectable by said first imaging modality,
wherein the second marker element extends generally along an axis and
the first marker element is radiopaque, encircles a portion of the second
marker element, and lies in a plane that is generally perpendicular to the
axis of the second marker element.
2. The marking device as claimed in claim 1 wherein said device is
nonpalpable.
3. The marking device as claimed in claim 1 wherein said first marker
element comprises a material selected from a group consisting of gold;
iridium; nickel; silver; stainless steel; tantalum; titanium; and alloys
thereof.
4. The marking device as claimed in claim 1 wherein said first marker
element comprises titanium.
5. The marking device as claimed in claim 1 wherein said first marker
element comprises a radiopaque additive.
6. The marking device as claimed in claim 5 wherein said radiopaque
additive is selected from the group consisting of barium-containing
compounds, bismuth-containing compounds, powdered tantalum,
powdered tungsten, barium carbonate, bismuth oxide, and barium sulfate.
7. The marking device as claimed in claim 1 wherein said first marker
element is spherical.
8. The marking device as claimed in claim 1 wherein said first marker
element is ring-shaped.
9. The marking device as claimed in claim 1 wherein said first marker
element has a V-shaped configuration.
10.The marking device as claimed in claim 1 wherein said first imaging
modality is a radiographic imaging modality.
11.The marking device as claimed in claim 10 wherein said radiographic
imaging modality is an x-ray.
12.The marking device as claimed in claim 11 wherein said x-ray is a
mammogram.
13.The marking device as claimed in claim 1 wherein said first imaging
modality is mammography.
14.The marking device as claimed in claim 1 wherein said second marker
element comprises a material selected from the group consisting of
fluoropolymers, polyester and polyester mixtures, polypropylene, and
nylon and nylon mixtures.
15.The marking device as claimed in claim 1 wherein said second marker
element comprises an echogenic coating.
16.The marking device as claimed in claim 1 wherein said second marker
element comprises a knotted suture.
17.The marking device as claimed in claim 1 wherein said second marker
element comprises a looped arrangement of suture.
18.The marking device as claimed in claim 1 wherein said second marker
element comprises a layered arrangement of sheet or mesh-like material.
19.The marking device as claimed in claim 1 wherein said second marker
element has a rolled configuration.
20.The marking device as claimed in claim 1 wherein said second marker
element has a geometry distinguishable from an anatomically occurring
artifact or tissue pathology.
21.The marking device as claimed in claim 1 wherein said second imaging
modality is ultrasonography.
22.The marking device as claimed in claim 1 wherein said first imaging
modality is x-ray and said second imaging modality is ultrasonography.
23.The marking device as claimed in claim 1 wherein said second
nonabsorbable marker element is resilient.
24.The marking device as claimed in claim 1 wherein said first marker
element comprises a metal and said second nonabsorbable marker
element comprises a polymer.
The invention relates to a marking device for identifying a subcutaneous biopsy
cavity comprising a first nonabsorbable marker element detectable by a first
imaging modality; and a second marker element detectable by a second imaging
modality but not detectable by said first imaging modality, wherein the second
marker element extends generally along an axis and the first marker element is
radiopaque, encircles a portion of the second marker element, and lies in a plane
that is generally perpendicular to the axis of the second marker element.

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Patent Number

224976

Indian Patent Application Number

02487/KOLNP/2005

PG Journal Number

44/2008

Publication Date

31-Oct-2008

Grant Date

29-Oct-2008

Date of Filing

05-Dec-2005

Name of Patentee

ETHICON ENDO-SURGERY, INC

Applicant Address

4545 CREEK ROAD CINCINNATI, OH

Inventors:

#	Inventor's Name	Inventor's Address
1	K. ANGELA MACFARLANE	1330 CRAZY PETES ROAD, WOODSIDE, CALIFORNIA 94062
2	SASCHA ZARINS	15403 SHANNON ROAD, LOS GATOS, CALIFORNIA 95032

PCT International Classification Number

A61B

PCT International Application Number

PCT/US2004/017368

PCT International Filing date

2004-06-01

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	60/476,533	2003-06-06	U.S.A.