Patent Application
20100160777
The present disclosure relates generally to deployment mechanisms for deploying site markers in connection with biopsy procedures.
In the diagnosis and treatment of cancer, it is often necessary to perform a biopsy to remove tissue samples from a suspicious mass. The suspicious mass is typically discovered during a preliminary examination involving visual examination, palpation, X-ray, magnetic resonance imaging (MRI), ultrasound imaging or other detection means.
When a suspicious mass is detected, a sample is talcen by biopsy, and then tested to determine whether the mass is malignant or benign. This biopsy procedure can be performed by an open surgical technique, or through the use of a specialized biopsy instrument such as stereotactic needle biopsy. To minimize surgical intrusion, a small specialized instrument such as a biopsy needle is inserted in the breast while the position of the needle is monitored using fluoroscopy, ultrasonic imaging, X-rays, MRI or other suitable imaging techniques.
Regardless of the method or instrument used to perform the biopsy, subsequent examination of the surgical site may be necessary, either in a follow up examination or for treatment of a cancerous lesion. In connection with breast biopsy procedures for example, treatment often includes a mastectomy, lumpectomy, radiation therapy, or chemotherapy procedure that requires the surgeon or radiologist to direct surgical or radiation treatment to the precise location of the lesion. Because this treatment might extend over days or weeks after the biopsy procedure, and the original features of the tissue may have been removed or altered by the biopsy, it is desirable to insert a site marker into the surgical cavity to serve as a landmark for future identification of the location of the lesion.
Commonly assigned application U.S. patent application Ser. No. 11,242,334 discloses markers that use expandable filament portions to ‘hold’ a site marker in place within a biopsy cavity. That is, a site marker may include a bio-absorbable filament portion, such as a suture, with a marker attached thereto, where the marker is visible under multiple modalities and the suture will inhibit migration of the marker within the biopsy cavity. The filament portions of these structures typically define a site marker diameter that is greater than the outer diameter of the cannula. To insert a site marker within a biopsy site, the site marker is compressed (at least partially elastically deformed) to a dimension that will permit the site marker to be interposed within the cannula, the site marker is interposed within an opening of the cannula, the site marker and cannula are sterilized, the cannula is inserted within the biopsy canal such that the opening is within the biopsy site, and the marker is deployed by projecting it into the biopsy site. Once deployed, the site marker will expand as the filament portions exit the cannula in reaction to the elastic deformation. The site marker will expand until the elastic deformation is eliminated or portions of the site marker interfere with the inside portions of the biopsy cavity.
Precise placement of site markers is important for subsequent evaluation of the biopsy area. Current methods of marker deployment generally include locating the outer cannula of the biopsy instrument in the area of the lesion, then depressing a plunger or pushrod within the cannula to force the marker into a biopsy cavity. When the plunger or pushrod is depressed, however, the site marker may not be placed exactly where intended. For instance, if the cannula is placed at the center of a biopsy cavity, the marker may move from the center of the cavity to one side, making the marker more difficult to subsequently locate. Furthermore, varying amounts of pressure on the pushrod may cause the site marker to extend further into the cavity than desired.
Accordingly, there is a need for a site marker deployment method which allows more precise placement of a site marker within a biopsy cavity.
A site marker deployment device is disclosed. The site marker deployment device comprises an inner member and a deployment cannula. The inner member has a distal end. The deployment cannula has an open distal end. The deployment cannula is slidably disposed over the inner member and a site marker that is disposed within the deployment cannula adjacent the inner member at the distal end of the depolyment cannula. The inner member is configured to be held generally stationary relative to a target location as deployment cannula is selectively moved between a pre-deployment configuration wherein the deployment cannula is positioned over at least a portion of the site marker and a deployed configuration wherein the deployment cannula is retracted such that the site marker is free from the deployment cannula.
a is an enlarged view of a distal end of a restraining member attached to a site marker.
Referring now to the drawings, illustrative embodiments are shown in detail. Although the drawings represent some embodiments, the drawings are not necessarily to scale and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the present disclosure. Further, the embodiments set forth herein are not intended to be exhaustive or otherwise limit or restrict the claims to the precise forms and configurations shown in the drawings and disclosed in the following detailed description. While the disclosure is described in connection with reference to a human breast, it is understood that the present disclosure may be employed with other areas of the body in which a site marker may be utilized.
Alternatively, the site marker delivery system of the present invention may be advanced through an introducer assembly that includes an outer introducer cannula 38. An exemplary introducer assembly is illustrated in commonly owned U.S. Pat. No. 7,347,829, the contents of which are incorporated by reference in its entirety. However, the system 22 illustrated in
Site marker 24 is disposed within deployment cannula 42, adjacent distal end 12 of inner member 10. The site marker 24 may be at least partially enclosed within a distal end 44 of deployment cannula 42, as shown in
The deployment device 40 may further include a retaining member 70, such as a trigger wire, disposed therein. The trigger wire 70 extends from a distal wire end 72 near a distal end 12 of the inner member 10 toward a proximal end 54 of the body 50. The illustrated trigger wire 70 is configured to retain a site marker 24 relative to the inner member 10, such as after sterilization and prior to enclosure within the deployment carnula 42. The site marker 24 may be held relative to the inner member 10 as deployment cannula 42 is extended axially relative to inner member 10, in the direction of the distal end 12 of the inner member 10, until the deployment cannula 42 at least partially encloses the site marker 24. The trigger wire 70 may further retain the site marker 24 relative to the inner member 10 while the deployment cannula 42 is inserted into the biopsy cavity 30 in the tissue 20 to a target location.
Referring to
In another exemplary embodiment, after deployment cannula 42 is inserted into biopsy cavity 30, deployment cannula 42 may be retracted by moving handle member in direction D, prior to trigger wire 70 being detached from site marker 24. Thus, in this exemplary embodiment, trigger wire 70 serves to hold site marker 24 against distal end 12 of inner member 10 within biopsy cavity 30, to insure proper placement of site marker 24 within biopsy cavity 30 prior to releasing site marker 24 from deployment device 40.
In yet another alternative embodiment (referring to
To ensure proper placement of the site marker 24 within the biopsy cavity 30 when the device 40 is placed in the target location, the site marker 24 is adjacent to the inner member 10 within the deployment cannula 42. The inner member 10 is held stationary relative to the target location by, for example, a tab 48 that is fixedly attached to body 50, as seen in FIGS. 1 and 5-6. More specifically, tab 48 may be slidably received within a notch 32 formed on a portion of a introducer member 36 that includes outer introducer cannula 38. Alternatively, tab 48 may be slidably received a notch that is formed on a proximal end of a biopsy device.
When the inner member 10 is in place, the deployment cannula 42 is withdrawn from the site marker 24 by retracting the handle member 52 in the direction of the arrow D, toward the proximal end 14 of the inner member 10. As the deployment cannula 42 is withdrawn, the inner member 10 cooperates with the site marker 24 to keep the site marker 24 in place. As the deployment cannula 42 is withdrawn, any friction between the site marker 24 and the deployment cannula 42 is overcome by the interaction between the site marker 24 and the inner member 10. By retracting the deployment cannula 42, as opposed to extending an inner member 10 outward of the distal end 44 of the deployment cannula 42, the precision with which the site marker 24 is placed at a desired location within a biopsy cavity is increased.
In one exemplary embodiment, one or more portions of site marker deployment system 22 may be constructed out of a radiolucent material, which is not visible under certain imaging modalities. Examples of suitable radiolucent materials include plastic, ceramic or glass. By constructing one or more portions of site marker deployment system 22 out of such radiolucent materials, the user will be able to confirm placement of the site marker 24 (while still encapsulated within the site marker delivery system 22) immediately prior to placement, but without compromising the ability of the imaging system to see any other suspicious areas underneath or around the site marker delivery system 22 during the imaging sequence.
Once deployment cannula 42 is pulled back in direction D, the inner member 10 keeps site marker 24 in place until site marker 24 is positioned outwardly from distal end 44 of deployment cannula 42. Once positioned outside of deployment cannula 42, site marker is biased to expand outwardly, thereby preventing re-entry of site marker 24 into deployment cannula 42. In one embodiment, once site marker 24 expands to its deployed configuration (
The deployment device 40 also includes a trigger wire 70 and an inner member 10 interposed within the deployment cannula 42. The trigger wire 70 extends from a distal end 12 of the inner member 10 to a proximal end (not shown). The site marker 24 includes filament members 92 connected to the marker end 90. A central filament member 92 extending from the marker end 90 may be looped to retain the permanent marker 94.
The trigger wire 70 and the inner member 10 may be held rigid while the deployment cannula 42 is extended generally in the direction of arrow E as the site marker 24 is enclosed within the deployment cannula 42 toward the position of
To deploy the site marker 24, the trigger wire 70 is pulled in the general direction of the arrow D as the deployment cannula 42 is held in a generally unmoved position relative to the inner member 10. Once the trigger wire 70 is pulled out of contact with the site marker 24, the deployment cannula 42 may be moved generally in the direction of the arrow D until the site marker 24 is no longer enclosed within the deployment cannula 42, thereby deploying the site marker 24.
Once released from the deployment device 40 and into the biopsy cavity 30, the site marker 24 automatically springs (due to the elastic deformation) into the deployed configuration having a size and shape generally defined by the biopsy cavity 30 such that the site marker 24 is easily visible under various imaging modalities.
In the embodiments illustrated, the permanent markers may be constructed of a material that is not absorbed by the body. Alternatively, the permanent markers may be a semi-permanent marker that bio-absorbs slower than the filament member. Because the movement of the permanent markers is restricted by the filament members prior to absorption thereof by the body, the permanent markers are restricted from migrating from within biopsy cavity. This insures that the permanent markers remain within the biopsy cavity to permit follow-up imaging of the biopsy site.
Since a site marker, such as the site marker 24, may be deployed with the aid of MRI, the user will visually detect when the site marker has been deployed and may confirm that the site marker has been successfully deployed in the desired location.
Referring now to
Referring now to
Turning now to
Once marker loading tool 47 is inserted into deployment cannula 42, trigger wire 70 is threaded through deployment cannula 42 so as to loop around a portion of site marker 24, which is positioned outwardly from distal end 44. Once looped around site marker 24, trigger wire 70 is then retracted in direction D so as to pull site marker 24 through marker loading tool 47. Because marker loading tool 47 includes an inwardly flared end 51, as positioned within deployment cannula 42, site marker 24 is compressed into a pre-deployment configuration (shown in
Although the steps of deploying the site markers described herein are listed in a particular order, the steps may be performed in differing orders or combined such that one operation may perform multiple steps. Furthermore, a step or steps may be initiated before another step or steps are completed, or a step or steps may be initiated and completed after initiation and before completion of (during the performance of) other steps.
While the embodiments of site markers 24 are described as having multiple filament members, it is understood that one or more filament members may be adequate to retain the marker in the desired biopsy cavity or other location. In addition, while the present invention has been particularly shown and described with reference to the foregoing preferred embodiments, it should be understood by those skilled in the art that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention without departing from the spirit and scope of the invention as defined in the following claims. It is intended that the following claims define the scope of the invention embodiments within the scope of these claims and their equivalents be covered thereby. This description of the invention should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. The foregoing embodiment is illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.
