Biopsy site marker with non-moving features

Abstract

The biopsy site marker includes a carrier and a marker element. The marker element includes a primary coil, a first anchor, and a second anchor. The first coil is disposed within the carrier. At least portions of the first anchor and the second anchor extend outward from opposite sides of the carrier. The first anchor and the second anchor are configured to move relative to the primary coil to engage tissue at the biopsy site.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Application No. 62 / 990,571, filed March 17, 2020, entitled "Non-Migrating Biopsy Site Identifiers," the disclosure of which is incorporated herein by reference. [Background technology]

[0002] Many patients undergo breast biopsy because of irregular mammograms and palpable abnormalities. Biopsies can include surgical excision biopsies and stereotactic and ultrasound-guided needle breast biopsies. In an image-directed biopsy, a radiologist or other physician may obtain a small sample of the irregular tissue for laboratory analysis. If the biopsy proves malignant, additional surgery (e.g., lumpectomy or mastectomy) may be necessary. In the case of a needle biopsy, the patient may return to the radiologist after one or more days, and the biopsy site (lesion) may need to be re-identified in preparation for surgery. An imaging system, such as ultrasound, magnetic resonance imaging (MRI), or X-ray, may be used to identify the biopsy site. A marker may be placed at the time of biopsy to assist in re-identifying the biopsy site.

[0003] The use of markers used after breast biopsy to mark the location where biopsied tissue has been removed is described in the following US patents: No. 6,083,524, issued July 4, 2000, entitled "Polymerizable biodegradable polymers including carbonate or dioxanone linkages"; U.S. Patent No. 6,162,241, issued December 4, 2000, entitled "Hemostatic tissue sealants"; U.S. Patent No. 6,270,464, issued August 7, 2001, entitled "Biopsy localization method and device"; U.S. Patent No. 6,356,782, issued March 12, 2002, entitled "Subcutaneous cavity marking device and method"; U.S. Patent No. 6,605,294, issued August 12, 2003, entitled "Methods of using in situ hydration of hydrogel articles for sealing or augmentation of tissue or vessels"; and U.S. Patent No. 8,600,481, issued December 3, 2013, entitled "Subcutaneous cavity marking device and method." No. 8,939,910, entitled "Method for enhancing ultrasound visibility of hyperechoic materials," issued on January 27, 2015, all of which are incorporated by reference in their entirety.

[0004] Once a marker is placed at a biopsy site, the marker can later be re-identified to identify the biopsy site in a subsequent follow-up procedure. In some contexts, the placed marker may not perfectly correspond to the biopsy site when the marker is re-identified. For example, the marker may move to another nearby location over the intervening time between the biopsy procedure and the subsequent follow-up procedure. Movement of the biopsy site marker can create difficulties in identifying the biopsy site during the subsequent follow-up procedure. Therefore, it may be desirable to incorporate features into the marker to maintain the marker in a fixed position over time.

[0005] Although several systems and methods have been made and used for marking biopsy sites, it is believed that no one prior to the present inventors has made or used the invention as set forth in the appended claims.

[0006] While the specification concludes with claims that particularly point out and distinctly claim the invention, the invention will be better understood from the following description of specific embodiments considered in conjunction with the accompanying drawings, in which like reference numerals refer to the same elements and in which some components or portions of components are shown in perspective, as represented by dashed lines. [Brief explanation of the drawings]

[0007] [Figure 1] 1A, 1B, and 1C show exemplary embodiments of biopsy site marker placement according to embodiments of the present disclosure. [Figure 2] 1 shows a perspective view of an exemplary marker delivery device. [Figure 3] 3 shows a vertical cross-sectional view of the marker delivery device of FIG. 2. [Figure 4] 10 shows a cross-sectional view of a marker deployed from the distal portion of the marker delivery device of FIG. 1 to a side opening in a biopsy needle to mark a biopsy site. [Figure 5A] 10 shows a top view of an exemplary alternative marker for use with the marker delivery device of FIG. 2, with the marker's carrier in a dehydrated state. [Figure 5B] 5B shows another top view of the marker of FIG. 5A, with the carrier of the marker in a partially hydrated state. [Figure 6A] 10 shows a top view of another exemplary alternative marker for use with the marker delivery device of FIG. 2, in which the marker element of the marker is in a linear configuration. [Figure 6B] 6B shows another top view of the marker of FIG. 6A, in which the marker element of the marker is in a curved configuration. [Figure 7A] 3 shows a top view of yet another exemplary alternative marker for use with the marker delivery device of FIG. 2. [Figure 7B] 7B shows a partial perspective view of the marker of FIG. 7A. [Figure 8] 3 shows a top view of yet another exemplary alternative marker for use with the marker delivery device of FIG. 2. [Figure 9] 9 shows a front view of the marker of FIG. 8. [Figure 10] 3 shows a top view of yet another exemplary alternative marker for use with the marker delivery device of FIG. 2. [Figure 11] 3 shows a top view of yet another exemplary alternative marker for use with the marker delivery device of FIG. 2. [Figure 12] 3 shows a top view of yet another exemplary alternative marker for use with the marker delivery device of FIG. 2. [Figure 13] 13 shows a front view of the marker of FIG. 12.

[0008] The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the invention may be embodied in a variety of other ways, including ways not necessarily shown in the drawings. The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several aspects of the invention and, together with the description, serve to explain the principles of the invention. It will be understood, however, that the invention is not limited to the precise configurations shown. DETAILED DESCRIPTION OF THE INVENTION

[0009] The following description of specific examples of the present invention should not be used to limit the scope of the present invention. Other examples, features, aspects, embodiments, and advantages of the present invention will be apparent to those skilled in the art from the following description, which is an example and one of the best modes contemplated for carrying out the invention. As will be recognized, the present invention is capable of other various and obvious aspects, all without departing from the present invention. Accordingly, the drawings and description should be regarded as illustrative in nature and not restrictive.

[0010] It can be beneficial to be able to mark the location or margins of a lesion, whether temporary or permanent, before or immediately after its removal or sampling. Marking before removal can help ensure that the entire lesion is excised, if necessary. Alternatively, if the lesion is unintentionally removed in its entirety, marking the biopsy site immediately after the procedure allows for its relocation for later identification.

[0011] Once the marker is positioned at the biopsy site, it may be desirable for the marker to remain visible under ultrasound. It may also be desirable for the marker to be easily distinguishable from other structural features of the patient. For example, it may be desirable for the marker to be distinguishable from microcalcifications under ultrasound visualization to avoid unintentionally characterizing the marker as a microcalcification during a subsequent ultrasound examination. Microcalcifications are generally used in the art to identify suspicious lesions or masses. Thus, it is generally desirable for ultrasound views to be distinguishable as markers and not unintentionally identified as new masses.

[0012] I. Exemplary Markers

[0013] The embodiments presented herein relate to devices and procedures for manufacturing a marker for percutaneously marking a biopsy cavity (10) with surrounding tissue (30), as shown in FIGS. 1A-1C. For example, as seen in FIG. 1A, a marker (100) may be initially placed in the biopsy cavity (10) to facilitate re-identification of the biopsy site. The marker (100) may include a carrier (120) and a marker element (12). The carrier (120) generally includes a bioabsorbable marker material (122). As such, the carrier (120) is generally configured to be absorbed into the patient's body after placement of the marker (100) within the biopsy cavity (10). In some examples, the carrier (120) may include a plurality of microbubbles that enhance visualization of the carrier (120) under ultrasound. As described in more detail below, the marker material (122) is generally bioabsorbable, thereby allowing the marker material (122) to be absorbed into the patient's tissue over time. In the present example, the marker material (122) comprises a hydrogel that is initially dehydrated. While a hydrogel is used in the present example, it should be understood that in other examples, the marker material (122) may comprise other known bioabsorbable materials.

[0014] In the present examples, the marker (100) further includes a marker element (12), which is generally not bioabsorbable. The marker element (12) may include a radiopaque or echogenic marker embedded within the bioabsorbable marker material (122) of the carrier (120). For example, the marker element (12) may include metal, hard plastic, or other radiopaque or hyperechoic material known to those skilled in the art in view of the teachings herein. In other examples, the marker (100) may be formed without the marker element (12). In yet other examples, the marker (100) may be formed solely with the marker element (12), thereby omitting the carrier (120) and leaving the marker element (12) in a "bare" form. In other words, in some examples, the marker (100) is formed solely from the carrier (120) as a bare clip.

[0015] The marker material (122) generally becomes expandable once placed at the biopsy site within the patient's body. As shown in FIGS. 1B and 1C, the initially dehydrated marker material (122) can absorb fluid from the surrounding tissue (30) into which it is inserted. In response to this fluid absorption, the marker material (122) can expand, thereby allowing the carrier (120) to fill the cavity created at the biopsy site by the removal of the tissue sample during the biopsy procedure. Biodegradable materials may be particularly suitable in applications where it is desirable to allow natural tissue growth to completely or partially replace the implant material over time, thus ensuring biocompatibility and restoring the tissue's natural mechanical parameters substantially to those of the pre-damaged state.

[0016] The marker 100 may be inserted into the body either surgically through an opening in the body cavity 30 or by a minimally invasive procedure using such a device as a catheter, introducer, or similar type of insertion device. The marker 100 may be delivered immediately after removal of the tissue specimen using the same device used to remove the tissue specimen itself. Follow-up non-invasive detection techniques, such as x-ray mammography or ultrasound, may then be used by the physician to identify, locate, and monitor the biopsy cavity site over a period of time with the marker 100.

[0017] The example markers (100) of the present invention are large enough to be easily visible to a clinician, for example, under an x-ray or ultrasound field of view, and small enough so as to be capable of being percutaneously deployed into a biopsy cavity without causing any difficulty to the patient. Although examples are described in connection with the treatment and diagnosis of breast tissue, the embodiments presented herein may be used for markers in any internal tissue, e.g., breast tissue, lung tissue, prostate tissue, lymph node tissue, etc.

[0018] Hydration of the marker material (122) in the carrier (120) by the natural moisture of the surrounding tissue causes the polymer to expand, thus minimizing the risk of migration. The growing hydrogel-based marker material (122) centers the marker (100) within the biopsy cavity as it grows. As the hydrogel expands, moisture naturally emerges from the surrounding tissue, and hydration allows sound to increase through transmission, resulting in increasingly hypoechoic areas that are easier to visualize on follow-up ultrasound scans.

[0019] Additionally, the hydratable hydrogel marker material (122) of the carrier (120) may be used to construct a permanent marker (12). The hypoechoic properties of the hydratable marker material (122) allow for ultrasound visibility of the permanent marker (12) within the hydrogel hydratable marker material (122) because the permanent marker (12) is outlined as a specular reflector within the hypoechoic hydratable marker material having a non-reflective substrate such as water.

[0020] II. Exemplary Marker Delivery Devices

[0021] In some instances, it may be desirable to deploy the above-described markers (100) within the body cavity (30) using a particular marker delivery device. For example, Figures 2 and 3 show an exemplary marker delivery device (150) including an elongated outer cannula (162) having a marker exit port, such as a side opening (164), formed adjacent the distal end of the cannula but spaced proximally from the distal end of the cannula (162).

[0022] A grip (166) can be provided at the proximal end of the cannula (162). A push rod (168) can be provided, extending coaxially within the cannula (162), such that the push rod (168) is configured to translate within the cannula (162) to displace one or more markers through the side opening (164) (see FIG. 3). The rod (168) can be sufficiently stiff in a compressed state to push the markers from the lumen (165) of the cannula (162) out through the opening (164), but can be relatively flexible in bending. A plunger (170) is coupled to the proximal end of the rod (168) for pushing the rod (168) distally within the cannula (162) to deploy the markers out of the cannula (162).

[0023] A user may grasp grip (166) with two fingers and use the thumb of the same hand to advance plunger (170), thereby operating marker delivery device (160) with one hand. A spring (not shown) or other feature may be provided about rod (168) to bias rod (168) proximally relative to grip (166) and cannula (162).

[0024] 3 shows a cross-sectional view of the distal portion of the marker delivery device (160). As can be seen, a biopsy marker (300), similar to the marker (100) described above, is disposed within the lumen (165) of the cannula (162). In the present example, the marker (300) includes a generally cylindrically shaped body of biodegradable or otherwise absorbable marker material (306), such as collagen or a hydrogel, and a metallic, generally radiopaque, permanent marker or marker element (310) disposed within or otherwise carried by the marker material (306).

[0025] The cannula 162 may be formed from any suitable metallic or non-metallic material. In some variations, the cannula 162 is formed from a thin-walled hollow tube formed from a suitable medical-grade plastic or polymer. One suitable material is a thermoplastic elastomer such as polyether block amide (PEBA), such as that known under the trade name PEBAX. The cannula 162 may be formed from PEBAX and may be substantially transparent to visible light and x-rays.

[0026] The side opening (164) may be formed by cutting out a portion of the wall of the cannula (162). The side opening (164) communicates with the lumen (165) of the cannula (162). The side opening (164) may extend axially (in a direction parallel to the axis of the lumen (165)) from the proximal open end (164A) to the distal open end (164B), as shown in FIG.

[0027] In the present example, as shown in FIG. 3, a distal tip (172) extends from the distal end of the cannula (162) and is rounded. Referring to FIG. 3, the distal end of the cannula (162) is closed by an integral end piece (171), a portion of which extends into the lumen (165) of the cannula (162). The end piece (171) may be a molded or cast component. The end piece (171) includes a tip (172), a ramp (210) having a beveled surface (212), and a marker engaging element (240). The beveled surface (212) helps direct the marker (300) from the lumen (165) through the side opening (164). The marker engaging element (240) helps keep the marker (300) within the lumen (165) until the user intends to deploy the marker (300).

[0028] Marker engaging element (240) is disposed within lumen (165), with at least a portion of marker engaging element (240) positioned distal to proximal end (164A) of side opening (164). Marker engaging element (240) extends along a portion of the bottom of cannula (162) below opening (164), such that marker engaging element (240) is positioned to reinforce the portion of cannula (162) in which opening (164) is formed. For example, by positioning marker engaging element (240) below opening (164), element (240) helps stiffen cannula (162) in the area where the wall of cannula (162) was cut to form opening (164), as shown in FIG. 3. As shown in FIG. 3, the marker engagement element (240) extends from the proximal-most portion of the bevel (212) and does not extend proximal to the side opening (164), although in other embodiments, a portion of the element (240) may extend proximal to the opening (164).

[0029] As shown in Figure 3, marker-engaging element (240) is in the form of a step having a generally uniform thickness (T) along the axial length of element (240), except that element (240) has a tapered proximal end (242). Tapered proximal end (242) forms an acute angle with the longitudinal axis of cavity (165) of approximately 45 degrees (the acute angle with the horizontal in Figure 3), while bevel (212) forms an acute angle with the longitudinal axis of cavity (165) of approximately 30 degrees. Of course, any number of other suitable angles may be used.

[0030] As shown in FIG. 3 , the upwardly facing surface 244 of the marker-engaging element 240 (the surface facing the opening 164) extends distally to contact the ramp 212, thereby eliminating any space or gap between the surface 244 and the ramp 212. Such an arrangement advantageously reduces the likelihood that the marker 300 will become trapped between the marker-engaging element 240 and the ramp 212 upon passing through the marker-engaging element 240. In some variations, the marker-engaging element 240, the ramp 210, and / or the tip 172 are formed from or include a material that is relatively more radiopaque than the walls of the cannula 162. For example, if the element 240, the ramp 210, and the tip 172 are formed as a unitary distal end 171, the distal end 171 may include a radiopaque additive, such as barium sulfate. For example, the distal end (171) can be a component molded from PEBAX with approximately 20 weight percent barium sulfate added to the molten PEBAX mold composition. The relatively more radiopaque marker engaging element (240), ramp (210), and tip (22) can be useful in distinguishing the location of those components using radiographic imaging. Also, when the steps of ramp (210) and / or engaging element (240) are positioned relative to opening (164), the addition of radiopaque material can help identify the location of opening (164) and the position of marker (300) relative to opening (164) before, during, or after deployment of marker (300).

[0031] Referring to FIG. 4, a marker delivery device 160 is used to deploy a marker 300 to mark a biopsy site within a patient. In FIG. 4, a cannulated biopsy needle 400 is shown having a piercing tip 402 and a closed distal end with a side tissue-receiving opening 414. The marker delivery device 160 is introduced into the biopsy site through the biopsy needle 400, which may be the same needle 400 used to collect tissue samples from the biopsy site. The biopsy needle 400 may be of the type used with a single-insertion, multiple-sample negative pressure biopsy device. Several such biopsy devices are disclosed in various patents and patent applications incorporated by reference herein, although other biopsy devices may be used.

[0032] Figure 4 shows the distal end of the marker delivery device (160) disposed within the needle (400). The needle (400) can be positioned within tissue, and a biopsy sample can be obtained through the side opening (414), thereby providing a biopsy cavity adjacent the side opening (414). The tissue sample is then obtained and transferred proximally through the needle (400), and the marker delivery device (160) is then inserted into the proximal opening within the needle (400) without removing the needle (400) from the patient's tissue. In Figure 4, the needle (400) and marker delivery device (160) are positioned such that the opening (164) of the cannula (162) and the side opening (414) of the needle (400) are substantially aligned axially and circumferentially. Next, with the marker delivery device (160) and needle (400) so positioned at the biopsy site, the push rod (168) is advanced, deploying the marker (300) up the bevel (212), through the opening (164), and then through the side opening (414) into the biopsy cavity.

[0033] III. Example of a biopsy site marker to limit migration

[0034] In some instances, it may be desirable to include certain features within a marker similar to marker (100) to reduce the risk of the marker migrating when placed within tissue. For example, some markers may be prone to migration after placement at a biopsy site due to tissue movement during the intervening time between placement of the marker and a subsequent follow-up procedure. As a result, such markers may create challenges with identifying the biopsy site during subsequent follow-up procedures. Therefore, it may be desirable to incorporate features similar to marker (100) into the marker to maintain the marker in a fixed position within the tissue over time. While several examples incorporating the features outlined above are described herein, it should be understood that various alternative combinations may be used without departing from the basic principles described herein.

[0035] A. Example of a biopsy site marker with multimodal fixation

[0036] 5A and 5B generally illustrate an exemplary marker (500) configured to anchor to tissue upon delivery at a biopsy site to limit movement of the marker (500) relative to its initial placement in the tissue. Additionally, the marker (500) is generally configured to improve anchoring over time in response to one or more conditions at the biopsy site, further contributing to limiting movement of the marker (500).

[0037] Similar to the marker 100 described above, the example marker 500 includes a carrier 520 and a marker element 512. Similar to the carrier 120 described above, the example carrier 520 generally includes a bioabsorbable marker material 522. Thus, the carrier 520 is generally configured for absorption into the patient's body following placement of the marker 500 within a biopsy cavity, such as the biopsy cavity 10 described above. While the example carrier 520 exhibits a generally cylindrical profile, various other shapes may be used. As also described above, some examples of the carrier 520 may include a plurality of microbubbles that enhance visualization of the carrier 520 under ultrasound.

[0038] The marker substance (522) in the present example comprises a hydrogel material or other suitable material. The hydrogel material is generally configured to be absorbed by the patient's tissue over time. Thus, the marker substance (522) is generally non-permanent. Furthermore, the hydrogel is generally configured to expand or swell when placed within tissue. As described in more detail below, the hydrogel may be dehydrated and / or cured before being deployed at the biopsy site or within the biopsy cavity. When the hydrogel contacts tissue, it may absorb water from the tissue and expand or swell as the hydrogel's water content increases. In some examples, the hydrogel may also be manipulated during dehydration and / or curing to control the expansion of the hydrogel according to various expansion profiles (e.g., limiting longitudinal expansion, limiting lateral expansion, and / or other). While the marker substance (522) is described herein as a hydrogel, it should be understood that in other examples, the marker substance (522) may comprise other suitable materials, with or without a hydrogel, or various combinations of suitable materials.

[0039] Similar to the marker element (12) described above, the marker element (512) of this example is at least partially disposed within a portion of the carrier (520). However, unlike the marker element (12), one or more portions of the marker element (512) are disposed outside of the carrier (520). As will be described in more detail below, this configuration of the marker element (512) is generally configured to facilitate fixation of the marker (500) within tissue.

[0040] The marker element (512) of the present example includes a primary anchor (530) (alternatively referred to as a "hypodermic syringe"), one or more secondary anchors (534) (alternatively referred to as "outriggers"), and a coil (536) connecting or joining the primary anchor (530) and the one or more secondary anchors (534). As described in more detail below, the anchors (530, 534) are generally configured to engage tissue and secure the marker (500) within the tissue.

[0041] The primary anchor (530) of the present example is generally configured to provide initial engagement and fixation with tissue. To facilitate such engagement, the primary anchor (530) includes a barb (532) disposed at the distal end of the primary anchor (530). Similar to a fishhook or other structure, the barb (532) is configured to penetrate tissue when force is applied in one direction (e.g., distally) but to hook or attach to tissue when force is applied in the opposite direction (e.g., proximally). Accordingly, it should be understood that the barb (532) may include a sharp distal end and an angled protrusion directed proximally from the sharp distal end. While the present example is shown as including a single barb (532), it should be understood that in other examples, multiple barbs (532) and / or proximally directed protrusions may be incorporated into the primary anchor (530) along its length.

[0042] The primary anchor (530) extends distally from the coil (536). At least a portion of the primary anchor (530) extends outside of the carrier (520), such that a portion of the primary anchor (530) is configured to engage tissue. As explained in more detail below, the particular length of extension of the primary anchor (530) generally relates to a predetermined expansion of the hydrogel of the carrier (520). For example, the extension of the primary anchor (530) generally is of sufficient length such that the barbs (532) remain engaged with tissue even after the carrier (520) is fully expanded within the tissue.

[0043] While examples of the present invention are shown as including a single primary anchor (530), in other examples, multiple primary anchors (530) may be used. For example, in some examples, two primary anchors (530) may extend distally from the coil (536) at an angle relative to the longitudinal axis defined by the carrier (520). In other examples, one primary anchor (530) may extend distally as shown, while another primary anchor (530) may extend proximally from the coil (536). In still other examples, multiple primary anchors (530) may extend proximally, distally, or both from the coil (536).

[0044] One or more secondary anchors (534) extend laterally from the coil (536) from the interior of the carrier (520) to the exterior of the carrier (520). Together, the one or more secondary anchors (534) are configured to further secure the marker (500) within tissue. As explained in more detail below, such securement may improve over time once the marker (500) is deployed within tissue, as each secondary anchor (534) is configured to respond to expansion of the carrier (520).

[0045] Each secondary anchor (534) comprises an elongated wire rod-shaped structure. Each secondary anchor (534) further extends outward from the coil (536). The extension of each secondary anchor (534) is shown lateral to or away from the longitudinal axis defined by the carrier (520). Additionally, each secondary anchor (534) is shown at an angle relative to the longitudinal axis defined by the carrier (520), such that each secondary anchor (534) also extends proximally (or away from the extension of the primary anchor (530)). In this orientation, each secondary anchor (534) is configured to allow movement of the marker (500) in one direction (e.g., distally) but prevent movement of the marker (500) in another direction (e.g., proximally).

[0046] Each secondary anchor (534) is configured to have approximately spring-like properties. For example, each secondary anchor (534) may be sufficiently flexible to bend, thereby allowing movement in one direction (e.g., distally), but may be sufficiently stiff to prevent movement of the marker (500) in the opposite direction (e.g., proximally). Such properties may be facilitated by the particular material of each secondary anchor (534), the dimensions (e.g., diameter) of each secondary anchor (534), or a combination of both.

[0047] The marker element (512) in the present example is shown as including two secondary anchors (534), one secondary anchor (534) protruding from each side of the carrier (520). In other examples, the marker element (512) may include any suitable number of secondary anchors (534). For example, in some examples, the marker element (512) may include multiple secondary anchors (534) extending from each side of the carrier (520). In other examples, the number of secondary anchors (534) may be asymmetric, with one secondary anchor (534) extending from one side of the carrier (520) and multiple secondary anchors (534) extending from another side of the carrier (520).

[0048] As described above, the coil 536 joins or connects the primary anchor 530 and each secondary anchor 536. The coil 536 includes one or more loops of wire material to enhance visualization of the marker element 512 under x-ray visualization at various angles relative to the x-ray source and detector. Additionally, the one or more loops of the coil 536 may be configured to secure the marker element 512 within the carrier 520, thereby providing a mechanical ground for the primary anchor 530 and each secondary anchor 536.

[0049] In the present example, the coil (536) is integral with the primary anchor (530) and each secondary anchor (536). However, in other examples, the coil (536) may be a separate component, with the primary anchor (530) and / or each secondary anchor (536) connected, secured, and / or fastened to the coil (536). In any event, in some examples, the coil (536) may be further configured to provide at least some resilience to each secondary anchor (536). Due to the integral construction, the coil (536), the primary anchor (530), and each secondary anchor (536) comprise a single common material, such as a metal. By way of example only, exemplary suitable materials for the coil (536), the primary anchor (530), and each secondary anchor (536) may include biocompatible alloys, such as nitinol, stainless steel, titanium, and / or others.

[0050] Figures 5A and 5B together illustrate an exemplary use of the marker 500. For example, Figure 5A shows the marker 500 in an initial, dehydrated configuration. Such a configuration may correspond to the marker 500 being loaded into a marker delivery device similar to the marker delivery device 150 described above. Such a configuration may also correspond to the state of the marker 500 immediately after deployment at a biopsy site.

[0051] In the initial, dehydrated configuration, the marker (500) can be inserted into the biopsy site using the marker delivery device (150) or any other suitable means. During insertion, the sharp tips defined by the barbs (532) of the primary anchors (530) can penetrate the tissue. This penetration sets the adjacent protrusions of the barbs (532) to set the axial position of the marker (500) and limit proximal movement of the marker (500) back through the cavity used to deploy the marker (500). The secondary anchors (534) can similarly facilitate insertion into the tissue by bending or otherwise moving in response to distal movement of the marker (500) through the tissue. The secondary anchors (534) can also limit proximal movement of the marker (500) back through the cavity used to deploy the marker (500) due to the proximal orientation of each secondary anchor (534).

[0052] After the marker (500) is deployed within tissue, the marker material (522) may absorb fluid from the surrounding tissue. This absorption results in the expansion or swelling of the carrier (520) over time, as shown in FIG. 5B. This expansion or swelling may cause a corresponding movement of each secondary anchor (534), thereby increasing the angle of each secondary anchor (534) relative to the longitudinal axis of the carrier (520). As the angle of each secondary anchor (534) increases, each secondary anchor (534) may improve the fixation of the marker (500) within the tissue. It should be understood that while at least some movement of each secondary anchor (534) may be facilitated by the expansion of the marker material (522), in some instances, at least some movement may be due to either the resilience of the secondary anchor (534) itself or the resilience provided by the coil (536).

[0053] B. Example of a biopsy site marker with a bending element

[0054] 6A and 6B generally illustrate an exemplary marker 600 configured to anchor to tissue upon delivery at a biopsy site, limiting movement of the marker 600 relative to its initial placement in the tissue. Similar to the marker 100 described above, the exemplary marker 600 includes a carrier 620 and a marker element 612. Similar to the carrier 120 described above, the exemplary carrier 620 generally includes a bioabsorbable marker material 622. Thus, the carrier 620 is generally configured to be absorbed into the patient's body after placement of the marker 600 within a biopsy cavity, such as the biopsy cavity 10 described above. While the exemplary carrier 620 exhibits a generally cylindrical profile, various other shapes may be used. As also described above, some exemplary carriers 620 may include a plurality of microbubbles to enhance visualization of the carrier 620 under ultrasound.

[0055] The marker substance (622) in the present example comprises a hydrogel material or other suitable material. The hydrogel material is generally configured to be absorbed by the patient's tissue over time. Thus, the marker substance (622) is generally non-permanent. Furthermore, the hydrogel is generally configured to expand or swell when placed within tissue. As described in more detail below, the hydrogel may be dehydrated and / or cured before being deployed at the biopsy site or within the biopsy cavity. When the hydrogel contacts the tissue, it may absorb water from the tissue and expand or swell as the hydrogel's water content increases. In some examples, the hydrogel may also be manipulated during dehydration and / or curing to control the expansion of the hydrogel according to various expansion profiles (e.g., limiting longitudinal expansion, limiting lateral expansion, and / or other). While the marker substance (622) is described herein as a hydrogel, it should be understood that in other examples, the marker substance (622) may comprise other suitable materials, with or without a hydrogel, or various combinations of suitable materials.

[0056] Unlike the carrier 120 described above, the carrier 620 is divided into two portions: a primary element 624 and a secondary element 626. As described in more detail below, the secondary element 626 is generally configured to move relative to the primary element 624 to improve fixation within tissue by the combination of the primary element 624 and the secondary element 626. In the present example, both the primary element 624 and the secondary element 626 are shown as having similar cylindrical shapes. However, it should be understood that in other examples, the primary element 624 and the secondary element 626 may have different shapes.

[0057] Similar to the marker element (12) described above, the marker element (612) of this example is at least partially disposed within a portion of the carrier (620). However, unlike the marker element (12), one or more portions of the marker element (612) are disposed outside of the carrier (620). For example, the marker element (612) extends from the primary element (624) to the secondary element (626), exposing a portion of the marker element (612) between the primary element (624) and the secondary element (626). As described in more detail below, this configuration of the marker element (612) is generally configured to facilitate fixation of the marker (600) within tissue by movement of the secondary element (626) relative to the primary element (624).

[0058] The marker element 612 includes a spring 630 (alternatively referred to as an "elastic member," "drive member," and / or "driver"), a primary coil 632, and a secondary coil 634. The spring 630 is disposed between the primary coil 632 and the secondary coil 634. In the present example, the spring 630 is shown as being centered between the primary coil 632 and the secondary coil 634, but it should be understood that in some examples, the spring 630 may be disposed off-center relative to the primary coil 632 and the secondary coil 634.

[0059] Regardless of the specific location of spring 630, spring 630 is positioned outside both primary element 624 and secondary element 626 of carrier 620. This configuration is generally desirable to enable movement of secondary element 626 relative to primary element 624 about an axis defined by spring 630. Thus, spring 630 is generally configured to energize movement of secondary element 626 and / or primary element 624.

[0060] The spring (630) may take a variety of forms suitable for energizing movement of the secondary element (626) relative to the primary element (624). In the present example, the spring (630) is shown as a coil or torsion spring. Such a configuration may also be desirable to improve visibility of the marker element (612) under x-ray by including one or more overlapping coils. However, other suitable configurations may be used. For example, in some examples, the spring (630) may include a shape memory material, such as nitinol. The spring (630) may then transition from a first, relatively straight shape to a second, bent shape in response to an increase in temperature from the surrounding tissue.

[0061] The primary coil 632 and the secondary coil 634 are disposed on opposite ends of the marker element 612. The primary coil 632 is disposed within the primary element 624 of the carrier 620, while the secondary coil 634 is disposed within the secondary element 626 of the carrier 620. Both coils 632, 634 define a distinctive geometric pattern that may be visible under x-ray and / or ultrasound. For example, in some instances, the coils 632, 634 may include one or more loops of wire material to improve visualization of the marker element 612 under x-ray visualization at various angles relative to the x-ray source and detector. Additionally, one or more loops of the coils 632, 634 may be configured to secure the marker element 612 within the primary element 624 / secondary element 626 of the carrier 620, thereby providing a mechanical ground for the marker element 612. In other examples, the coils 632, 634 may be in a ribbon or sheet configuration bent at one or more points to provide enhanced visualization under x-ray and / or ultrasound. In any of the above configurations of each coil 632, 634, such coils 632, 634 may include one or more openings and / or bores to further enhance visualization. Furthermore, each coil 632, 634 is not necessarily identical in configuration. Indeed, in some examples, it may be desirable to have at least some variation between the configurations of each coil 632, 634 to more easily identify a particular end of the marker 600.

[0062] Each coil (632, 634) in this example is integral with the rest of the marker element (612). Such a configuration may be desirable to facilitate ease of manufacturing, for example, by requiring only a single wire to be bent. However, in other examples, each coil (632, 634) may be a separate component, with the remainder of the marker element (612) connected, secured, and / or fastened to each coil (632, 634). Due to the integral construction, the marker element (612) comprises a single common material, such as a metal. By way of example only, exemplary suitable materials for each coil (632, 634) and other components of the marker element (612) may include biocompatible alloys, such as nitinol, stainless steel, titanium, and / or others.

[0063] 6A and 6B together illustrate an exemplary use of the marker 600. For example, FIG. 6A illustrates the marker 600 in an initial, linear configuration. Such a configuration may correspond to the marker 600 being loaded into a marker delivery device similar to the marker delivery device 150 described above. While the marker 600 is in the linear configuration, the marker 600 is generally configured for deployment to a biopsy site using the marker delivery device.

[0064] When the marker 600 is deployed at the biopsy site, the marker 600 is configured to automatically transition to a bent configuration as shown in FIG. 6B. As can be seen, the spring 630 is configured to activate the movement of the secondary element 626 relative to the primary element 624 about an axis defined by the spring 630. This transition causes the marker 600 to assume a more irregular shape, thereby increasing the likelihood of fixation within the tissue at the biopsy site. In the present example, a rotation of approximately 90° is shown. However, it should be understood that various other rotations may be used in other examples. By way of example only, one range of suitable rotation angles may include approximately 70° to approximately 100°.

[0065] As discussed above, the spring (630) may be configured to activate movement of the secondary element (626) in a variety of ways. In the present example, such movement is achieved by the spring (630) being resiliently biased, rotating the secondary element (626) from the position shown in FIG. 6A to the position shown in FIG. 6B. In another example, the spring (630) may include a shape memory alloy. Such an alloy may be sensitive to the temperature of the surrounding tissue and, therefore, may slowly activate movement of the secondary element (626) over time as the spring (630) warms from ambient temperature to tissue temperature. Such a configuration may be desirable to facilitate movement of the secondary element (626) at least partially concurrently with the expansion and / or inflation of the carrier (620).

[0066] C. Example of a biopsy site marker with multiple anchor elements

[0067] 7A and 7B generally illustrate an exemplary marker 700 configured to be secured to tissue using anchors oriented across multiple planes to limit movement of the marker 700 relative to its initial placement in the tissue. Similar to the marker 100 described above, the exemplary marker 700 includes a carrier 720 and a marker element 712. Similar to the carrier 120 described above, the exemplary carrier 720 generally includes a bioabsorbable marker material 722. Thus, the carrier 720 is generally configured to be absorbed into the patient's body after placement of the marker 700 within the biopsy cavity 10 described above. While the exemplary carrier 720 exhibits a generally cylindrical profile, various other shapes may be used. As also described above, some exemplary carriers 720 may include a plurality of microbubbles to enhance visualization of the carrier 720 under ultrasound.

[0068] The marker substance (722) in the present example comprises a hydrogel material or other suitable material. The hydrogel material is generally configured to be absorbed by the patient's tissue over time. Thus, the marker substance (722) is generally non-permanent. Furthermore, the hydrogel is generally configured to expand or swell when placed within tissue. As described in more detail below, the hydrogel may be dehydrated and / or cured before being deployed at the biopsy site or within the biopsy cavity. When the hydrogel contacts tissue, it absorbs water from the tissue and may expand or swell as the hydrogel's water content increases. In some examples, the hydrogel may also be manipulated during dehydration and / or curing to control the expansion of the hydrogel according to various expansion profiles (e.g., limiting longitudinal expansion, limiting lateral expansion, and / or other). While the marker substance (722) is described herein as a hydrogel, it should be understood that in other examples, the marker substance (722) may comprise other suitable materials, with or without a hydrogel, or various combinations of suitable materials.

[0069] The marker element 712 includes a braided portion 730 and a plurality of anchor portions 732 (alternatively referred to as "outriggers") extending distally from the braided portion 730. In some examples, the braided portion 730 is disposed entirely within the carrier 720. In other examples, at least a portion of the braided portion 730 may extend outside of the carrier 720. The braided portion 730 is defined by a plurality of wires braided together in a repeating pattern. A variety of suitable repeating patterns may be used. Generally, a suitable repeating pattern may be configured to provide a distinctive pattern that enhances visualization under x-ray and / or ultrasound visualization.

[0070] The anchor portions (732) extend distally from the braided portion (730). In the present example, the braided portion (730) includes three wires, and the anchor portions (732) are formed by three corresponding unbraided wires. Alternatively, in other examples, any suitable number of wires, such as two, four, five, or six, may be used. Each anchor portion (732) projects outward from the distal end of the braided portion (730) at a different angle than the other anchor portions (732) and is configured to traverse multiple different planes. In this configuration, each anchor portion (732) is configured to engage tissue across multiple planes, rather than traversing a single plane.

[0071] 7A and 7B illustrate exemplary uses of the marker 700. For example, FIG. 7A shows the marker 700 in a configuration that, in some instances, may correspond to a configuration after deployment at a biopsy site using a marker delivery device similar to the marker delivery device 150 described above. In this position, the anchor portions 732 are generally compressed or closer together than in a fully secured configuration. While the anchor portions 732 are further shown as having some space between them, it should be understood that in other applications, the anchor portions 732 may be positioned closer together for deployment. For example, in some applications, the anchor portions 732 may be pressed together to form a substantially straight distal projection. This configuration may be desirable to facilitate smoother deployment using a marker delivery device similar to the marker delivery device 150 described above. In other applications, such a straight configuration of the anchor portions 732 may be further facilitated by braiding the anchor portions 732 in a pattern similar to that of the braided portions 730. In such a configuration, such braiding of anchor portions (732) may be relatively loose to facilitate subsequent spreading of anchor portions (732) relative to one another.

[0072] After deployment, the anchor portions 732 expand in multiple different directions, as shown in Figure 7B. As a result of this expansion, each anchor portion 732 interdigitates with the tissue at the biopsy site in multiple different planes. As a result, the anchor portions 732 are configured together to secure the marker 700 within the tissue in multiple directions (e.g., laterally and longitudinally).

[0073] D. Example of a biopsy site marker with multiplanar anchor elements

[0074] 8 and 9 generally illustrate an exemplary marker 800 configured to secure tissue using anchors aligned along multiple planes to limit movement of the marker relative to its initial placement. Similar to the marker 100 described above, the exemplary marker 800 includes a carrier 820 and a marker element 812. Similar to the carrier 120 described above, the exemplary carrier 820 generally includes a bioabsorbable marker material 822. Thus, the carrier 820 is generally configured to be absorbed into the patient's body after placement of the marker 800 within the biopsy cavity 10 described above. While the exemplary carrier 820 exhibits a generally cylindrical profile, various other shapes may be used. As also described above, some exemplary carriers 820 may include a plurality of microbubbles to enhance visualization of the carrier 820 under ultrasound.

[0075] The marker substance (822) in the present example comprises a hydrogel material or other suitable material. The hydrogel material is generally configured to be absorbed by the patient's tissue over time. Thus, the marker substance (822) is generally non-permanent. Furthermore, the hydrogel is generally configured to expand or swell when placed within tissue. As described in more detail below, the hydrogel may be dehydrated and / or cured before being deployed at the biopsy site or within the biopsy cavity. When the hydrogel contacts the tissue, it may absorb water from the tissue and expand or swell as the hydrogel's water content increases. In some examples, the hydrogel may also be manipulated during dehydration and / or curing to control the expansion of the hydrogel according to various expansion profiles (e.g., limiting longitudinal expansion, limiting lateral expansion, and / or other). While the marker substance (822) is described herein as a hydrogel, it should be understood that in other examples, the marker substance (822) may comprise other suitable materials, with or without a hydrogel, or various combinations of suitable materials.

[0076] The marker element 812 includes a primary coil 830 and a plurality of anchors 832, 838, 844, 850 (alternatively referred to as "outriggers") extending outward from the primary coil 830. In the present example, the primary coil 830 is disposed entirely within a carrier 820. The primary coil 830 is defined by one or more wire coils. Generally, the combination of the one or more wire coils forming the primary coil 830 is configured to provide a distinctive pattern for enhanced visualization under x-ray and / or ultrasound visualization. While the present example shows the primary coil 830 having a particular orientation within the carrier 820, it should be understood that in other examples, the primary coil 830 may have a variety of alternative orientations.

[0077] Each anchor (832, 838, 844, 850) extends proximally or distally away from the primary coil (830) and protrudes from the carrier (820). Each anchor (832, 838, 844, 850) includes a corresponding secondary coil (834, 840, 846, 852) and spring (836, 842, 848, 854). Each secondary coil (834, 840, 846, 852) is generally configured as one or more wire loops and is configured to promote tissue ingrowth to provide improved fixation of the marker (800). Each spring (836, 842, 848, 854) is positioned along the length of each anchor (832, 838, 844, 850) between the primary coil (830) and each secondary coil (834, 840, 846, 852). As described in more detail below, each spring (836, 842, 848, 854) is configured to bias each secondary coil (834, 840, 846, 852) outwardly and inwardly of the tissue. Thus, each spring (836, 842, 848, 854) is positioned along the length of each anchor (832, 838, 844, 850) outside of the carrier (820). While the anchors (832, 838, 844, 850) in the examples of the present invention are shown as being substantially similar to one another, it should be understood that in other examples, the anchors (832, 838, 844, 850) may vary in structure. For example, in some examples, one or more of the anchors (832, 838, 844, 850) may include multiple springs, multiple coils, and / or different geometric profiles. Furthermore, in some examples, the anchors (832, 838, 844, 850) may vary in length, with one of the anchors (832, 838, 844, 850) being longer or shorter than one or more of the other anchors (832, 838, 844, 850). Various suitable combinations of such features will be apparent to those skilled in the art in view of the teachings herein.

[0078] The present example includes a first anchor (832) and a second anchor (838) extending distally from the carrier (820) and a third anchor (844) and a fourth anchor (850) extending proximally from the carrier (820). As best shown in FIG. 9 , the first anchor (832) and the second anchor (838) are laterally offset relative to one another. Similarly, the third anchor (844) and the fourth anchor (850) are also laterally offset relative to one another. In some cases, such a lateral offset may be desirable due to an asymmetric fixation profile. For example, a lateral offset may facilitate rotation or some movement of the cylindrical shape of the marker (800). However, in the present example, the anchors (832, 838, 844, 850) are positioned to balance any asymmetry. For example, the first anchor (832) and the third anchor (844) may be aligned along a common plane. Similarly, the second anchor 838 and the fourth anchor 850 can be aligned in another common plane that is offset from the common plane of the first anchor 832 and the third anchor 844. As a result, the marker 800 can have a more balanced fixation profile, improving the fixation provided by the several anchors 832, 838, 844, 850.

[0079] In an exemplary use, the marker (800) may be initially positioned in a tubular structure, similar to the outer cannula (162) of the marker delivery device (150), for deployment at a biopsy site. To facilitate containment within the tubular structure, the anchors (832, 838, 844, 850) may bend around the springs (836, 842, 848, 854) to conform to the inner diameter of the tubular structure.

[0080] During deployment of the marker 800, the marker 800 may be released from the tubular structure, as similarly described above with respect to the marker delivery device 150. As the marker 800 is released from the tubular structure, the elastic biasing force of the springs 836, 842, 848, 854 may cause the anchors 832, 838, 844, 850 to expand. As a result, each secondary coil 834, 840, 846, 852 of each anchor 832, 838, 844, 850 may be pressed into adjacent tissue to secure the marker 800 at the biopsy site. Over time, some tissue ingrowth may occur with respect to each secondary coil 834, 840, 846, 852, further improving the fixation of the marker 800 over time.

[0081] FIG. 10 illustrates an exemplary marker 900 similar to marker 800 described above. For example, like marker 800, example marker 900 of the present invention includes a carrier 920 and a marker element 912. Example carrier 920 of the present invention is substantially similar to carrier 820 described above. For example, carrier 920 is generally configured to be absorbed into the patient's body after placement of marker 900 within the biopsy cavity. Similarly, carrier 920 may include a hydrogel or other suitable material configured to expand upon hydration and be absorbed by the patient's tissue over time.

[0082] The marker element 912 is substantially similar to the marker element 812 described above. For example, like the marker element 812, the marker element 912 of this example includes a primary coil 930 having a plurality of anchors 932, 938, 944, 950 extending away from the primary coil. Similarly, each anchor 932, 938, 944, 950 includes a secondary coil 934, 940, 946, 952 and a spring 936, 942, 948, 950, with the springs 936, 942, 948, 950 positioned between the primary coil 930 and the secondary coils 934, 940, 946, 952. Similar to the springs (836, 842, 848, 850) described above, the springs (936, 942, 948, 950) of the present example are positioned outside the carrier (920) and are resiliently biased to promote engagement of each secondary coil (934, 940, 946, 952) with tissue.

[0083] Unlike the anchors (832, 838, 844, 850) described above, the anchors (932, 938, 944, 950) in the present example all extend distally away from the primary coil (930). In other words, each anchor (932, 938, 944, 950) extends in the same direction relative to the other anchors (932, 938, 944, 950). To accommodate this relationship, the present example includes anchors (932, 938, 944, 950). For example, in the present example, the inner anchors (944, 950) have a length greater than the outer anchors (932, 938), providing adequate clearance between all of the anchors (932, 938, 944, 950). While specific lengths for the anchors (932, 938, 944, 950) are shown in the present example, various alternative lengths may be used in other examples. Alternatively, the orientation of each anchor (932, 938, 944, 950) may be modified to provide clearance between the anchors (932, 938, 944, 950) rather than changing their length.

[0084] Although not shown, it should be understood that example anchors (932, 938, 944, 950) of the present invention may be laterally offset relative to the other anchors (932, 938, 944, 950), as similarly described above with respect to anchors (832, 838, 844, 850). For example, in some instances, lateral anchors (932, 938) may be laterally aligned with adjacent medial anchors (944, 950), such that the lateral anchors (932, 938) and adjacent medial anchors (944, 950) extend along a common plane. Conversely, the lateral anchors (944, 950) may be laterally offset relative to one another. As similarly described above with respect to anchors (832, 838, 844, 850), such lateral offsets may be desirable to provide multiple fixation points oriented along two or more distinct planes.

[0085] In an exemplary use, the marker (900) may be used in a manner similar to that described above with respect to the marker (800). For example, the marker (900) may be initially placed in a tubular structure, similar to the outer cannula (162) of the marker delivery device (150), for deployment at the biopsy site. To facilitate containment within the tubular structure, the anchors (932, 938, 944, 950) may bend around the springs (936, 942, 948, 954) to conform to the inner diameter of the tubular structure.

[0086] During deployment of the marker 900, the marker 900 may be released from the tubular structure, as similarly described above with respect to the marker delivery device 150. As the marker 900 is released from the tubular structure, the elastic biasing force of the springs 936, 942, 948, 954 may cause the anchors 932, 938, 944, 950 to expand. As a result, each secondary coil 934, 940, 946, 952 of each anchor 932, 938, 944, 950 may be pressed into adjacent tissue to secure the marker 900 at the biopsy site. Over time, some tissue ingrowth may occur with respect to each secondary coil 934, 940, 946, 952, further improving the fixation of the marker 900 over time.

[0087] E. Example of a biopsy site marker with nitinol tubing

[0088] FIG. 11 generally illustrates an exemplary marker 1000 configured to automatically change shape upon delivery at a biopsy site and limit movement of the marker 1000 relative to its initial placement in tissue. Similar to the marker 100 described above, the exemplary marker 1000 includes a carrier 1020 and a marker element 1012. Similar to the marker 120 described above, the exemplary carrier 1020 generally includes a bioabsorbable marker material 1022. Thus, the carrier 1020 is generally configured to be absorbed into the patient's body after placement of the marker 1000 within the biopsy cavity 10 described above. While the exemplary carrier 1020 exhibits a generally cylindrical profile, various other shapes may be used. As also described above, some exemplary carriers 1020 may include a plurality of microbubbles to enhance visualization of the carrier 1020 under ultrasound.

[0089] The marker substance (1022) in the present example comprises a hydrogel material or other suitable material. The hydrogel material is generally configured to be absorbed by the patient's tissue over time. Thus, the marker substance (1022) is generally non-permanent. Furthermore, the hydrogel is generally configured to expand or swell when placed within tissue. As described in more detail below, the hydrogel may be dehydrated and / or cured before being deployed at the biopsy site or within the biopsy cavity. When the hydrogel contacts tissue, it may absorb water from the tissue and expand or swell as the hydrogel's water content increases. In some examples, the hydrogel may also be manipulated during dehydration and / or curing to control the expansion of the hydrogel according to various expansion profiles (e.g., limiting longitudinal expansion, limiting lateral expansion, and / or other). While the marker substance (1022) is described herein as a hydrogel, it should be understood that in other examples, the marker substance (1022) may comprise other suitable materials, with or without a hydrogel, or various combinations of suitable materials.

[0090] Unlike the carrier 120 described above, the carrier 1020 is divided into two portions: a distal element 1024 and a proximal element 1026. As described in more detail below, the distal element 1024 and the proximal element 1026 are generally spaced apart from one another by a predetermined distance, thereby allowing movement of a portion of the marker 1000 relative to the distal element 1024 and the proximal element 1026. Thus, the distal element 1024 and the proximal element 1026 together form a generally cylindrical shape, which is interrupted by a space between the distal element 1024 and the proximal element 1026. In the present example, both the distal element 1024 and the proximal element 1026 are shown as having a similar cylindrical shape. However, it should be understood that in other examples, the distal element 1024 and the proximal element 1026 may have different shapes.

[0091] Similar to the marker element 12 described above, the marker element 1012 of this example is at least partially disposed within a portion of the carrier 1020. However, unlike the marker element 12, one or more portions of the marker element 1012 are disposed outside of the carrier 1020. For example, the marker element 1012 extends from the distal element 1024 to the proximal element 1026, with a portion of the marker element 1012 between the distal element 1024 and the proximal element 1026 being exposed. As described in more detail below, this configuration of the marker element 1012 is generally configured to facilitate fixation of the marker 1000 within tissue by movement of one or more of the marker element 1012, the distal element 1026, and / or the proximal element 1024.

[0092] The marker element (1012) includes an anchor tube (1030) (alternatively referred to as a "tube," "expansion member," and / or "cross member"), a distal connector (1032), and a proximal connector (1034). The anchor tube (1030) is disposed between the distal connector (1032) and the proximal connector (1034). In the present example, the anchor tube (1030) includes multiple nitinol wires oriented relative to each other to form a tubular structure. As explained in more detail below, this configuration of the anchor tube (1030) is configured to allow expansion of the anchor tube (1030) in response to heat from the surrounding tissue, thereby securing the marker (1000) by engaging the wires forming the anchor tube (1030) with the surrounding tissue. While in the present example, the anchor tube (1030) is formed from multiple wires, it should be understood that in other examples, the anchor tube (1030) may take a variety of forms using a variety of materials. For example, in some instances, anchor tube (1030) may be a tubular sheet of material having holes and / or slots extending therethrough, hi such instances, anchor tube (1030) may comprise nitinol, other biocompatible shape memory alloys, or biocompatible non-shape memory alloys.

[0093] The distal connector 1032 is disposed at one end of the anchor tube 1030, and the proximal connector 1034 is disposed at the other end of the anchor tube 1030. Each connector 1032, 1034 is at least partially disposed within an element 1024, 1026 of the carrier 1020. Thus, each connector 1032, 1034 provides a mechanical ground between the anchor tube 1030 and the respective element 1024, 1026 of the carrier 1020. Additionally, each connector 1032, 1034 may be configured to enhance visualization of the marker 1000 under ultrasound. For example, in some instances, each connector 1032, 1034 may include one or more wire coils configured to provide a distinctive pattern under x-ray and / or ultrasound visualization. In other examples, each connection (1032, 1034) may comprise a ribbon or sheet material that is bent or twisted in several places to provide a distinctive pattern under x-ray and / or ultrasound visualization.

[0094] In some examples, each connector (1032, 1034) may be integral with the anchor tube (1030). Accordingly, in such examples, each connector (1032, 1034) and the anchor tube (1030) may comprise the same material as the anchor tube (1030). In other examples, each connector (1032, 1034) may comprise a different material relative to the anchor tube (1030). In such examples, each connector (1032, 1034) may be integral with the anchor tube (1030) using an overmolding, forging, or other similar process. Alternatively, each connector (1032, 1034) may be separate from the anchor tube (1030) and connected thereto using one or more fasteners, adhesives, and / or other suitable mechanical connections.

[0095] In an exemplary use, the marker (1000) may be in an initial configuration in which the anchor tube (1030) is in a generally tubular configuration similar to that shown in Figure 11. Such a configuration may correspond to the marker (1000) being loaded into a marker delivery device similar to the marker delivery device (150) described above. While the marker (1000) is in the initial configuration, the marker (1000) is generally configured for deployment to a biopsy site using the marker delivery device.

[0096] When the marker (1000) is placed at the biopsy site, the marker (1000) is configured to automatically transition to an expanded configuration. During this transition, the anchor tube (1030) gradually absorbs heat from the surrounding tissue. This heat absorption activates the shape memory property of the anchor tube (1030). In this example, the wires that make up the anchor tube (1030) may be configured with a curved pattern that is larger than the radius defined by the carrier (1020) upon activation of the shape memory property. As a result, the anchor tube (1030) expands upon activation of the shape memory property, and the wires that form the anchor tube (1030) engage the surrounding tissue with increasing force. Once expansion is complete, the anchor tube (1030) may be configured to secure the marker (1000) within the tissue.

[0097] F. Example of a biopsy site marker with an anchor having a multi-spring configuration

[0098] 12 and 13 generally illustrate an exemplary marker 1100 configured to secure tissue using anchors aligned along multiple planes to limit movement of the marker 1100 relative to its initial placement in the tissue. Similar to the marker 100 described above, the exemplary marker 1100 includes a carrier 1120 and a marker element 1112. Similar to the carrier 120 described above, the exemplary carrier 1120 generally includes a bioabsorbable marker material 1122. Thus, the carrier 1120 is generally configured to be absorbed into the patient's body after placement of the marker 1100 within a biopsy cavity, such as the biopsy cavity 10 described above. While the exemplary carrier 1120 exhibits a generally cylindrical profile, various other shapes may be used. As also described above, some exemplary carriers 1120 may include a plurality of microbubbles to enhance visualization of the carrier 1120 under ultrasound.

[0099] The marker substance (1122) in the present example comprises a hydrogel material or other suitable material. The hydrogel material is generally configured to be absorbed by the patient's tissue over time. Thus, the marker substance (1122) is generally non-permanent. Furthermore, the hydrogel is generally configured to expand or swell when placed within tissue. As described in more detail below, the hydrogel may be dehydrated and / or cured before being deployed at the biopsy site or within the biopsy cavity. When the hydrogel contacts the tissue, it may absorb water from the tissue and expand or swell as the hydrogel's water content increases. In some examples, the hydrogel may also be manipulated during dehydration and / or curing to control the expansion of the hydrogel according to various expansion profiles (e.g., limiting longitudinal expansion, limiting lateral expansion, and / or other). While the marker substance (1122) is described herein as a hydrogel, it should be understood that in other examples, the marker substance (1122) may comprise other suitable materials, with or without a hydrogel, or various combinations of suitable materials.

[0100] The marker element 1112 includes a primary coil 1130 and a plurality of anchors 1132, 1142 (alternatively referred to as "outriggers") extending outward from the primary coil 1130. In the present example, the primary coil 1130 is disposed entirely within the carrier 1120. The primary coil 1130 is defined by one or more wire coils. Generally, the combination of the one or more wire coils forming the primary coil 1130 is configured to provide a distinctive pattern for improved visualization under x-ray and / or ultrasound visualization. While in the present example, the primary coil 1130 is shown as having a particular orientation within the carrier 1120, it should be understood that in other examples, the primary coil 1130 may have a variety of alternative orientations.

[0101] Each anchor (1132, 1142) extends distally away from the primary coil (1130) and protrudes from a portion of the carrier (1120). Each anchor (1132, 1142) includes a corresponding first spring (1134, 1144), second spring (1136, 1146), and secondary coil (1138, 1148). Each secondary coil (1138, 1148) is generally configured as one or more wire loops and is configured to promote tissue ingrowth to provide improved fixation of the marker (1100). Each of the first spring (1134, 1144) and second spring (1136, 1146) is positioned along the length of each anchor (1132, 1142) between the primary coil (1130) and its respective secondary coil (1138, 1148). As described in further detail below, each of the first springs (1134, 1144) and second springs (1136, 1146) is configured to bias the respective secondary coils (1138, 1148) outwardly and inwardly of the tissue, and thus each of the first springs (1134, 1144) and second springs (1136, 1146) is positioned along the length of each anchor (1132, 1142) outside of the carrier (1120).

[0102] While the anchors 1132, 1142 in the examples of the present invention are shown as being substantially similar to one another, it should be understood that in other examples, the anchors 1132, 1142 may vary in structure. For example, in some examples, one or more of the anchors 1132, 1142 may include additional springs, multiple coils, and / or different geometric profiles. Furthermore, in some examples, the anchors 1132, 1142 may vary in length, with one of the anchors 1132, 1142 being longer or shorter than one or more of the other anchors 1132, 1142. Various suitable combinations of such features will be apparent to those skilled in the art in view of the teachings herein.

[0103] The present example includes a first anchor (1132) and a second anchor (1142) extending distally from the carrier (1120). As best shown in FIG. 13, the first anchor (1132) and the second anchor (1142) are laterally offset relative to one another. Such a lateral offset may be desirable to facilitate fixation along multiple offset planes. For example, the first anchor (1132) of the present example is configured to provide fixation along one plane, while the second anchor (1142) is configured to provide fixation along another plane that is laterally offset from the plane associated with the first anchor (1132).

[0104] In an exemplary use, the marker 1100 may be initially positioned in a tubular structure, such as the outer cannula 162 of the marker delivery device 150, for deployment at a biopsy site. To facilitate containment within the tubular structure, the anchors 1132, 1142 may bend around the first springs 1134, 1144 and / or the second springs 1136, 1146 to conform to the inner diameter of the tubular structure.

[0105] During deployment of the marker 1100, the marker 1100 may be released from the tubular structure, as similarly described above with respect to the marker delivery device 150. As the marker 1100 is released from the tubular structure, the elastic biasing force of the springs 1134, 1136, 1144, 1146 may cause the anchors 1132, 1142 to expand, thereby increasing the lateral profile or span of the marker 1100. As a result, each secondary coil 1138, 1148 of each anchor 1132, 1142 may be pushed into adjacent tissue to secure the marker 1100 at the biopsy site. Over time, some tissue ingrowth may occur against each secondary coil 1138, 1148, further improving the fixation of the marker 1100 over time.

[0106] IV. Exemplary Combinations

[0107] The following examples illustrate various, non-exhaustive methods in which the teachings herein may be combined or applied. It should be understood that the following examples are not intended to limit the scope of any claims that may be presented at any time in this application or in any subsequent application thereto. No disclaimer is intended. The following examples are presented merely for illustrative purposes. It is contemplated that the various teachings herein may be arranged and applied in many other ways. It is also contemplated that some variations may omit certain features referred to in the examples below. Accordingly, none of the aspects or features referred to below should be considered critical unless expressly indicated otherwise, such as by the inventor at a later date or by the intended inventor's successors. If any claims are presented in this application or in any subsequent application related to this application that include additional features other than those referred to below, these additional features should not be presumed to have been added for any reason regarding patentability.

[0108] Example 1

[0109] 1. A biopsy site marker comprising: a carrier; and a marker element including a primary coil, a first anchor, and a second anchor, wherein the primary coil is disposed within the carrier, at least a portion of the first anchor and the second anchor extend laterally and outwardly away from the primary coil and from opposite sides of the carrier, and the first anchor and the second anchor are configured to move relative to the primary coil to engage tissue at a biopsy site.

[0110] Example 2

[0111] 2. The marker of example 1, wherein the first anchor and the second anchor extend laterally from the primary coil at an angle relative to a longitudinal axis defined by the carrier.

[0112] Example 3

[0113] The marker of any one of Examples 1 to 2, wherein the carrier comprises a hydrogel marker material.

[0114] Example 4

[0115] A marker as described in Example 3, wherein the hydrogel marker material is configured to expand in the presence of moisture, and the first anchor and the second anchor are configured to improve engagement of the first anchor and the second anchor with tissue in response to expansion of the hydrogel marker material.

[0116] Example 5

[0117] The marker element further includes a third anchor, the third anchor extending distally from the primary coil, and a portion of the third anchor disposed outside the carrier.

[0118] Example 6

[0119] The marker of example 5, wherein the third anchor comprises one or more barbs, the one or more barbs configured to penetrate and capture tissue.

[0120] Example 7

[0121] 7. The marker of embodiment 6, wherein the first anchor and the second anchor each include a secondary coil, the secondary coil being disposed at an outer end of each of the first anchor and the second anchor.

[0122] Example 8

[0123] 8. The marker of any one or more of Examples 1-7, wherein the primary coil is elastically biased to drive the first anchor and the second anchor toward a predetermined position.

[0124] Example 9

[0125] The marker of Example 8, wherein the predetermined positions of the first anchor and the second anchor are positioned distal to an initial position defined by the first anchor and the second anchor.

[0126] Example 10

[0127] The marker of Example 9, wherein the marker is configured to deploy from a cannula when the first anchor and the second anchor are positioned in the initial position.

[0128] Example 11

[0129] The marker of any one or more of Examples 1-11, wherein the first anchor or the second anchor defines a spring disposed outside the carrier.

[0130] Example 12

[0131] 12. The marker of claim 11, wherein the spring is configured to drive a portion of the first anchor or the second anchor into tissue.

[0132] Example 13

[0133] A marker described in any one or more of Examples 1 to 12, wherein the first anchor and the second anchor are connected to the primary coil at a first position and a second position, respectively, and the first position is laterally offset relative to the second position.

[0134] Example 14

[0135] A marker described in any one or more of Examples 1 to 13, wherein the first anchor and the second anchor comprise a shape memory alloy and are configured to engage tissue when exposed to heat, thereby activating the shape memory properties of the shape memory alloy.

[0136] Example 15

[0137] The marker of Example 14, wherein the first anchor and the second anchor are configured to form a predetermined curve when exposed to heat.

[0138] Example 16

[0139] 1. A biopsy site marker comprising: a carrier having a first element and a second element; and a marker element extending between the first element and the second element of the carrier, the marker element having an elastic portion configured to transition the marker element between a pre-deployed state and a deployed state, the elastic portion further configured to move the second element of the carrier relative to the first element when the marker element is transitioned between the pre-deployed state and the deployed state.

[0140] Example 17

[0141] The biopsy site marker of Example 16, wherein the elastic portion comprises a spring.

[0142] Example 18

[0143] 18. The biopsy site marker of claim 16 or 17, wherein the elastic portion is configured to move the second element of the carrier by approximately 90 degrees relative to the first element of the carrier.

[0144] Example 19

[0145] 19. The biopsy site marker of any one or more of Examples 16-18, wherein the marker element further comprises a first coil and a second coil, the first coil and the second coil being disposed at opposite ends of the marker element, the first coil being disposed within the first element of the carrier, and the second coil being disposed within the second element of the carrier.

[0146] Example 20

[0147] 1. A biopsy site marker comprising: a carrier; and a marker element, the marker element including a braided portion disposed within the carrier; and a plurality of anchor portions extending from the braided portion to an exterior of the carrier.

[0148] Example 21

[0149] 21. The biopsy site marker of Example 20, wherein each anchor portion of the plurality of anchor portions is configured to move from each adjacent anchor portion to secure the marker to tissue.

[0150] Example 22

[0151] A biopsy site marker as described in Example 20 or 22, wherein the carrier comprises a hydrogel marker material configured to expand in the presence of moisture, and the hydrogel marker material is configured to activate movement of the multiple anchor portions by expansion of the hydrogel marker material in the presence of moisture.

[0152] Example 23

[0153] 1. A biopsy site marker comprising: a carrier; and a marker element, the marker element including a body defining a coil shape, a first anchor, and a second anchor, the body being at least partially disposed within the carrier, the first anchor including first and second springs disposed between the body and an outer end of the first anchor, and the second anchor including third and fourth springs disposed between the body and an outer end of the second anchor.

[0154] Example 24

[0155] 24. The biopsy site marker of Example 23, wherein the first anchor comprises a secondary coil disposed at the outer end of the first anchor, and the second anchor comprises a secondary coil disposed at the outer end of the second anchor.

[0156] Example 25

[0157] 25. The biopsy site marker of Example 23 or 24, wherein the first spring, the second spring, the third spring, and the fourth spring are configured to increase the span of the biopsy site marker across the lateral dimension.

[0158] Example 26

[0159] 25. The biopsy site marker of any one or more of Examples 23-24, wherein the marker element further comprises a third anchor and a fourth anchor, the first anchor and the second anchor extending distally from the body, and the third anchor and the fourth anchor extending proximally from the body.

[0160] Example 27

[0161] 27. The biopsy site marker of Example 26, wherein the third anchor includes a fifth spring disposed between the body and an outer end of the third anchor, and the fourth anchor includes a sixth spring disposed between the body and an outer end of the fourth anchor.

[0162] Example 28

[0163] A biopsy site marker as described in Example 26, wherein the third anchor includes a fifth spring and a sixth spring disposed between the main body and the outer end of the third anchor, and the fourth anchor includes a seventh spring and an eighth spring disposed between the main body and the outer end of the fourth anchor.

[0164] V. Conclusion

[0165] Any patent, publication, or other disclosure material that is believed to be incorporated herein by reference should be understood to be incorporated herein, in whole or in part, only to the extent that the incorporated material does not contradict existing definitions, descriptions, or other disclosure material set forth in this disclosure. Accordingly, and to the extent necessary, the disclosure as expressly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is believed to be incorporated herein by reference but that contradicts existing definitions, descriptions, or other disclosure material set forth herein is incorporated only to the extent that no contradiction arises between the incorporated material and the existing disclosure material.

[0166] While various embodiments of the present invention have been shown and described, further adaptations of the methods and systems described herein may be achieved by those skilled in the art through appropriate modifications without departing from the scope of the present invention. While some of such possible modifications have been mentioned, others will be apparent to those skilled in the art. For example, the examples, embodiments, geometries, materials, dimensions, proportions, steps, etc. described above are illustrative and not required. Accordingly, it will be understood that the scope of the present invention should be considered in terms of the following claims, and is not limited to the details of structure and operation shown and described in the specification and drawings.

[0167] [Embodiment] (1) A biopsy site marker, Career and a marker element including a primary coil, a first anchor, and a second anchor; the primary coil is disposed within the carrier, and at least a portion of the first anchor and the second anchor extend laterally and outwardly away from the primary coil and from opposite sides of the carrier; The biopsy site marker, wherein the first anchor and the second anchor are configured to move relative to the primary coil to engage tissue at a biopsy site. (2) A marker as described in embodiment 1, wherein the first anchor and the second anchor extend laterally from the primary coil at an angle relative to a longitudinal axis defined by the carrier. (3) The marker of any one of claims 1 to 2, wherein the carrier comprises a hydrogel marker material. (4) the hydrogel marker material is configured to expand in the presence of moisture; A marker as described in embodiment 3, wherein the first anchor and the second anchor are configured to improve engagement of the first anchor and the second anchor with tissue in response to expansion of the hydrogel marker material. (5) A marker described in any one of embodiments 1 to 4, wherein the marker element further includes a third anchor, the third anchor extending distally from the primary coil, and a portion of the third anchor being positioned outside the carrier.

[0168] (6) A marker as described in embodiment 5, wherein the third anchor includes one or more barbs, the one or more barbs being configured to penetrate and capture tissue. (7) A marker as described in embodiment 6, wherein the first anchor and the second anchor each include a secondary coil, and the secondary coil is disposed at an outer end of each of the first anchor and the second anchor. (8) A marker described in any one of embodiments 1 to 7, wherein the primary coil is elastically biased to drive the first anchor and the second anchor toward a predetermined position. (9) A marker as described in embodiment 8, wherein the predetermined positions of the first anchor and the second anchor are positioned distal to the initial positions defined by the first anchor and the second anchor. (10) The marker described in embodiment 9, wherein the marker is configured to be deployed from a cannula when the first anchor and the second anchor are positioned in the initial position.

[0169] (11) A marker described in any one of embodiments 1 to 10, wherein the first anchor or the second anchor defines a spring disposed outside the carrier. (12) The marker of embodiment 11, wherein the spring is configured to drive a portion of the first anchor or the second anchor into tissue. (13) A marker described in any one of embodiments 1 to 12, wherein the first anchor and the second anchor are connected to the primary coil at a first position and a second position, respectively, and the first position is laterally offset from the second position. (14) The first anchor and the second anchor include a shape memory alloy, A marker described in any of embodiments 1 to 13, wherein the first anchor and the second anchor are configured to engage tissue when exposed to heat, thereby activating the shape memory properties of the shape memory alloy. (15) A marker as described in embodiment 14, wherein the first anchor and the second anchor are configured to form a predetermined curve when exposed to heat.

[0170] (16) A biopsy site marker, a carrier having a first element and a second element; a marker element extending between the first and second elements of the carrier; The biopsy site marker, wherein the marker element has an elastic portion configured to transition the marker element between a pre-deployed state and a deployed state, and the elastic portion is further configured to move the second element of the carrier relative to the first element when the marker element is transitioned between the pre-deployed state and the deployed state. (17) The biopsy site marker of embodiment 16, wherein the elastic portion comprises a spring. (18) The biopsy site marker of embodiment 16 or 17, wherein the elastic portion is configured to move the second element of the carrier by approximately 90° relative to the first element of the carrier. (19) The marker element further includes a first coil and a second coil; A biopsy site marker as described in any of embodiments 16 to 18, wherein the first coil and the second coil are positioned at opposite ends of the marker element, the first coil being positioned within the first element of the carrier, and the second coil being positioned within the second element of the carrier. (20) A biopsy site marker, Career and a marker element; The marker element includes a braided portion disposed within the carrier and a plurality of anchor portions extending from the braided portion to an exterior of the carrier. The biopsy site marker.

[0171] (21) The biopsy site marker of embodiment 20, wherein each anchor portion of the plurality of anchor portions is configured to move from each adjacent anchor portion to secure the marker to tissue. (22) A biopsy site marker as described in embodiment 20 or 21, wherein the carrier comprises a hydrogel marker material configured to expand in the presence of moisture, and the hydrogel marker material is configured to activate movement of the plurality of anchor portions by expansion of the hydrogel marker material in the presence of moisture. (23) A biopsy site marker, Career and a marker element; The biopsy site marker, wherein the marker element includes a body defining a coil shape, a first anchor, and a second anchor, the body being at least partially disposed within the carrier, the first anchor including a first spring and a second spring disposed between the body and an outer end of the first anchor, and the second anchor including a third spring and a fourth spring disposed between the body and an outer end of the second anchor. (24) The first anchor includes a secondary coil disposed at the outer end of the first anchor; 24. The biopsy site marker of claim 23, wherein the second anchor includes a secondary coil disposed at the outer end of the second anchor. (25) The biopsy site marker of embodiment 23 or 24, wherein the first spring, the second spring, the third spring, and the fourth spring are configured to increase the span of the biopsy site marker across the lateral dimension.

[0172] (26) The marker element further comprises a third anchor and a fourth anchor; the first anchor and the second anchor extend distally from the body; A biopsy site marker according to any one of embodiments 23 to 24, wherein the third anchor and the fourth anchor extend proximally from the main body. (27) The third anchor includes a fifth spring disposed between the body and an outer end of the third anchor; 27. A biopsy site marker as described in embodiment 26, wherein the fourth anchor includes a sixth spring disposed between the body and the outer end of the fourth anchor. (28) The third anchor includes a fifth spring and a sixth spring disposed between the body and an outer end of the third anchor; 27. A biopsy site marker as described in embodiment 26, wherein the fourth anchor includes a seventh spring and an eighth spring disposed between the body and the outer end of the fourth anchor.

Claims

1. A biopsy site marker comprising: a carrier comprising a hydrogel material, the hydrogel material configured to absorb water from the tissue when the hydrogel material contacts the tissue and expand as the water content of the hydrogel material increases; a marker element including a primary coil, a first anchor, and a second anchor; the primary coil is disposed within the carrier, and at least a portion of the first anchor and the second anchor extend laterally and outwardly away from the primary coil through the carrier; the first anchor and the second anchor are configured to move relative to the primary coil to engage tissue at a biopsy site; a biopsy site marker, wherein the first anchor and the second anchor are configured to enhance engagement of the first anchor and the second anchor with the tissue at the biopsy site in response to the expansion of the hydrogel material.

2. The biopsy site marker of claim 1 , wherein the first anchor and the second anchor extend laterally from the primary coil at an angle relative to a longitudinal axis defined by the carrier.

3. 3. The biopsy site marker of claim 2, wherein the expansion of the hydrogel material causes movement of each of the first anchor and the second anchor such that the angle of each of the first anchor and the second anchor relative to the longitudinal axis increases.

4. The biopsy site marker of claim 3 , wherein the hydrogel material is dehydrated before being deployed at the biopsy site.

5. The biopsy site marker of claim 4 , wherein the carrier defines a cylindrical profile.

6. 6. A biopsy site marker according to claim 1, wherein the marker element further comprises a third anchor, the third anchor extending distally from the primary coil, and a portion of the third anchor being positioned outside the carrier.

7. The biopsy site marker of claim 6 , wherein the third anchor includes one or more barbs, the one or more barbs configured to penetrate and capture tissue.

8. The biopsy site marker of claim 7 , wherein the first anchor and the second anchor each include a secondary coil, the secondary coil being disposed at an outer end of each of the first anchor and the second anchor.

9. The biopsy site marker of any of claims 6 to 8, wherein the third anchor extends at least in part along a longitudinal axis defined by the carrier.

10. The biopsy site marker of any preceding claim, wherein the primary coil is resiliently biased to drive the first anchor and the second anchor towards a predetermined position.

11. The biopsy site marker of claim 10 , wherein the predetermined positions of the first anchor and the second anchor are located distal to an initial position defined by the first anchor and the second anchor.

12. The biopsy site marker of claim 11 , wherein the biopsy site marker is configured to deploy from a cannula when the first anchor and the second anchor are disposed in the initial position.

13. The biopsy site marker of any preceding claim, wherein the first anchor or the second anchor defines a spring disposed externally of the carrier.

14. The biopsy site marker of claim 13 , wherein the spring is configured to drive a portion of the first anchor or the second anchor into tissue.

15. 15. The biopsy site marker of claim 1, wherein the first anchor and the second anchor are connected to the primary coil at a first position and a second position, respectively, and the first position is laterally offset from the second position.

16. the first anchor and the second anchor include a shape memory alloy; 16. A biopsy site marker according to any preceding claim, wherein the first anchor and the second anchor are configured to engage tissue when exposed to heat, thereby activating the shape memory properties of the shape memory alloy.

17. 17. The biopsy site marker of claim 16, wherein the first anchor and the second anchor are configured to form a predetermined curve when exposed to heat.

18. The biopsy site marker of claim 1 , wherein the hydrogel material is dehydrated and / or hardened prior to deployment at the biopsy site.

19. The biopsy site marker of claim 18 , wherein the carrier defines a cylindrical profile.

Images