System and apparatus for rapid stereotactic breast biopsy analysis

A stereotactic breast biopsy apparatus and system that may comprise an x-ray source, a digital imaging receptor, and a biopsy specimen cassette, wherein the digital imaging receptor is adjustably secured to the apparatus to permit an unobstructed illumination of the biopsy specimen and thereby produce biopsy x-ray images directly in the procedure room for immediate analysis. Some examples of the benefits may be, but are not limited to, a more rapid analysis of biopsy specimen digital images, post-processing image capability, and decreased procedure time and diminution of patient bleeding complications and needle discomfort.

TECHNICAL FIELD

Exemplary embodiments of the present invention relate to methods (e.g., medical non-surgical) of diagnosing breast cancer and, more particularly, to a novel apparatus, system, and method which beneficially improves current stereotactic breast biopsy devices and methods.

BACKGROUND OF THE ART

Stereotactic breast biopsy has become the method of choice for the non-surgical diagnosis of many forms of breast cancer. Many breast cancers are discovered by the presence of microcalcifications visible on a screening mammogram. Yet, these microcalcifications do not have a corresponding palpable abnormality. Therefore, an image-guided needle biopsy technique must be utilized to determine if early, pre-invasive breast cancer is present. Currently, stereotactically guided needle biopsy procedures represent the state-of-the-art for the common situation outlined above.

However, though very safe and minimally invasive, stereotactic breast biopsy can be laborious, time-consuming and uncomfortable for the patient. The procedure requires the patient to be prone. In order to immobilize the breast, physical compression must be applied to the breast during the procedure, and the patient must remain motionless. Procedure times are typically between 30-45 minutes, despite recent advances in vacuum-assisted biopsy needle technology. A significant component of procedure time continues to be consumed by the film development cycles required for specimen radiograph production.

A specimen radiograph is an ex-vivo x-ray picture of the biopsy samples or specimen “threads” retrieved from the breast. Under conventional circumstances, this radiograph must be performed outside the procedure room on a standard mammography x-ray unit. This picture is required to assure that sufficient quantities of microcalcifications are removed from the groups of calcium targeted within the breast. This process proves that the biopsy procedure will be adequate for subsequent analysis by surgical pathology. The process of performing specimen radiography is standard-of-care for stereotactic breast biopsy. Each specimen radiograph cycle can last 5-10 minutes, thereby adding 20-30% additional procedure time. If the original specimen radiograph demonstrates a paucity of microcalcifications, additional biopsy samples must be harvested, and the specimen radiograph cycle must be repeated.

SUMMARY OF THE INVENTION

One exemplary embodiment of the present invention is a modification and improvement to the commercially available stereotactic biopsy systems (e.g., LORAD Medical Systems Corp., Danbury, Conn. or Fischer Medical Technologies, Inc., Denver, Colo.). This modification may allow the stereotactic, swing-arm x-ray source (currently used solely to guide the biopsy procedure) to be used in the rapid production of specimen radiography. In one exemplary embodiment, a mechanical track may allow the x-ray source to shift laterally from the working biopsy corridor (occupied by the patient's breast during a procedure) allowing the x-ray source beam to be aligned with an add-on digital imaging receptor card which may be added to the lateral aspect of the existing imaging receptor. The harvested biopsy specimen threads may be positioned in, for example, specimen slots on a disposable specimen cassette or holder. The disposable specimen holder may then be attached to the add-on digital imaging receptor card between the x-ray source and digital imaging receptor card to allow for instant production of specimen radiographs within the procedure room. In another exemplary embodiment, an optional ancillary digital imaging receptor may be adjustably secured to at least a portion of the biopsy system to allow viewing of the harvested biopsy specimens without having to shift the axis of the x-ray source. Other exemplary embodiments are possible as set forth herein.

Some examples of the benefits may include, but are not limited to, the following:

a) Production of instant digital (rather than analog) specimen radiographs in the procedure room can be achieved. This feature can reduce procedure time up to 30%, thereby improving patient tolerance of the procedure.

b) Bleeding complications and needle discomfort can be diminished, as the typical number of samples harvested by the operator may decrease with exemplary embodiments of the present invention. There may no longer be a disincentive to “view” the biopsy sample early in the procedure, after a few samples have been retrieved.
c) The digital specimen radiograph can be “post-processed” (filtered and windowed) to assure adequate visualization of very small, subtle microcalcifications, (many of which may be less than 0.1 mm in diameter). This feature may improve the accuracy of stereotactic biopsy. With analog specimen radiography, these types of microcalcifications can be very difficult to reliably identify, resulting in the need for additional biopsy retrieval.
d) Decreased procedure time may allow for more procedures to be performed within a given time and level of staffing commitment. This may improve the economic viability of this procedure for biopsy centers.

These and other advantages may be provided by exemplary embodiments of the present invention, as described in more detail below.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENT(S)

FIG. 1illustrates a typical specimen radiograph showing a needle aspirated biopsy specimen45and microcalcifications55. Biopsy specimens similar to45may be harvested from a patient's breast25typically via a plurality of samples collected from a target area35. The specimen radiograph is an ex-vivo x-ray picture of the biopsy samples retrieved from the breast, which under conventional circumstances, must be processed outside the procedure room, on a standard mammography x-ray unit or on a separately purchased commercially available unit, such as one produced by Faxitron X-ray Corporation, Wheeling, Ill. In the current state of the art, this picture is required to assure that sufficient quantities of microcalcifications are removed from the groups of calcium targeted within the breast.

FIGS. 2,3, and4illustrate a typical example of a commercially available stereotactic biopsy system10produced by LORAD Medical Systems Corp., Danbury, Conn. During a typical biopsy collection procedure, a patient is positioned in a prone position on table20. The patient's breast under examination is allowed to protrude through a port30in table20and is captured and stabilized between a digital imaging receptor40and needle stage50. The x-ray source60illuminates the breast with x-ray radiation forming an image on the digital imaging receptor40, located on the distal side of the breast relative to x-ray source60, for subsequent image processing. The collected x-ray image is reviewed and post-processed on a connected computer console and system in the procedure room. Foundation80and base90are rotatably connected which allows the physician to orient the x-ray source60and digital imaging receptor40to produce stereotactic image pairs that allow the physician to accurately position the tip of the biopsy needle (in x, y, and z coordinates) within the patient's breast.

Referring now toFIGS. 5 and 6, the x-ray source60, which is fixedly attached to foundation80, projects a radiation beam along a working biopsy corridor along beam axis110(occupied by the patient's breast during a procedure). During a typical biopsy harvesting procedure, a specimen radiograph is produced via an ex-vivo x-ray image of the biopsy samples retrieved from the breast. Under conventional circumstances, this radiograph must be performed outside the procedure room on a standard mammography x-ray unit or on a separately purchased Faxitron unit. This radiograph is required to assure that sufficient quantities of microcalcifications are removed from the groups of calcium targeted within the breast. This process proves that the biopsy procedure will be adequate for subsequent analysis by surgical pathology. Each specimen radiograph cycle can last 5-10 minutes, thereby adding 20-30% additional procedure time. If the original specimen radiograph demonstrates a paucity of microcalcifications, additional biopsy samples must be harvested and the specimen radiograph cycle must be repeated.

To provide quicker results, an exemplary embodiment of this invention may beneficially reduce the time needed to conduct the ex-vivo x-ray image processing steps described heretofore by allowing the physician to process and review x-ray images within a procedure room by means of modifications and improvements to, for example, commercially available stereotactic biopsy systems (e.g., LORAD, Fischer Medical Technologies, etc.). An example of this modification comprises a means by which the stereotactic, swing-arm x-ray source60(currently used solely to guide the biopsy procedure) may be, for example, displaced or rotated for use in concert with an imaging receptor to allow the rapid production of specimen radiography. In another example, the modification may include an add-on ancillary digital imaging receptor70. In one example, the digital imaging receptor70may enage the underside face of the table20.

FIGS. 7 through 11illustrate an example of one exemplary embodiment of the present invention wherein a mechanical track system65, which may be slidably attached to foundation80and support x-ray source60, allows the x-ray source60to be laterally displaced from the working biopsy corridor along beam axis110(otherwise occupied by the patient's breast during a procedure). An add-on ancillary digital imaging receptor70is introduced and preferably positioned adjacent to digital imaging receptor40, whereby the now displaced x-ray source beam120(shown inFIG. 10) may be aligned with a digital imaging receptor70to allow x-ray beam axis120to impinge normally upon the ancillary digital imaging receptor face150, such as shown in the example ofFIGS. 12 and 13.

A biopsy specimen retention device for retaining collected biopsy samples within the apparatus for analysis may be provided by a wide variety of mechanical support schemes. As shown as one example inFIGS. 11a,11b, and11c, harvested biopsy specimens45may be positioned in a specimen “cassette”130that may be fixedly or removably attached to an ancillary digital imaging receptor70, which may be, in-turn, fixedly or removably associated with digital imaging receptor40.

In one exemplary embodiment, it may be preferable that the specimen cassette130be fabricated of x-ray transparent materials that are low in cost so as to promote disposability, such as paper-based materials or plastics, which may include, for example, polyethylene, polypropylene, polycarbonates, and polystyrenes, among others.FIG. 11aillustrates one example of a cassette130design which comprises a cassette base180that is hingedly attached to a cassette lid170via hinges190. FIGS.11band11cillustrate one example of a cassette lid170closure scheme. Other cassette base and cassette lid closure schemes are possible. For example, one exemplary embodiment may include the use of interlocking tongues and grooves on the cassette base180and cassette lid170, which may allow for a slideable connection between cassette lid170and cassette base180instead of hinges190. A single or plurality of specimen channels140may, for example, be formed as grooves within cassette base180. Such specimen channels may provide cavities by which a single or plurality of biopsy specimens45may be captured within cassette130upon closure of cassette lid170. The cassette130may allow biopsy specimens45to be positioned between the x-ray source60and ancillary digital imaging receptor70within beam120, thereby allowing expeditious and direct biopsy image processing for instant production of specimen radiographs within the procedure room via a computer control monitor with consequent benefits heretofore described.

FIGS. 12 and 13illustrate one example of one means by which cassette130may be removably attached to ancillary digital receptor70. In this example, flanges200may be used to removably associate cassette130with ancillary digital imaging receptor face150. Other means to removably associate cassette130with the ancillary digital imaging receptor face150may comprise, but are not limited to, hook and loop fasteners, contact adhesives, magnets, tongue and groove connections, mechanical fasteners, and other similar or suitable means.

FIGS. 14 and 15illustrate an example of another exemplary embodiment wherein the x-ray source60is provided with a means to be rotatably connected about a longitudinal axis to foundation80, whereby the x-ray source beam may be rotationally displaced from a working biopsy corridor beam axis110to position120. In this example, ancillary digital imaging receptor70may be rigidly or adjustably associated with digital imaging receptor40or with a convenient point on foundation80. Support means for x-ray source60may allow selective positioning of x-ray beam axis120so as to be normal to the ancillary digital imaging receptor face150shown inFIGS. 12 and 13in this exemplary embodiment.

Other embodiments include, but are not limited to, means of rotationally and/or laterally displacing the x-ray source about or relative to any axis or axes to provide sufficient displacement of an x-ray source beam from a working biopsy corridor beam axis110to allow unobstructed x-ray source illumination of a collected biopsy specimen45contained within a specimen cassette130associated with an ancillary digital imaging receptor70. It should be further noted that ancillary digital imaging receptor70may be fixedly or removably attached to a movable and adjustable support means (e.g., a cart, etc.) separate from (but in a suitable working vicinity of) a foundation80in some exemplary embodiments.

FIGS. 16 and 17illustrate an additional embodiment, which includes a means for laterally and/or rotationally displacing an x-ray source60, as heretofore taught, in concert with similar means for laterally and/or rotationally displacing a digital imaging receptor40to allow sufficient displacement of a radiation beam axis120from a working biopsy corridor110, thereby allowing direct use of the digital imaging receptor40and eliminating the need for an ancillary digital imaging receptor70. This latter embodiment may provide a means for capturing and stabilizing a breast by a breast support plate160, which may be separately connected to foundation80, allowing independent use and free movement of the digital imaging receptor40. Furthermore, this exemplary embodiment may include a biopsy specimen cassette130that may be fixedly or removably associated with digital imaging receptor40in a manner similarly taught heretofore.

In another example, as seen inFIGS. 18,19, and20, the ancillary digital imaging receptor70may be adjustably secured to at least a portion of the patient table20. In exemplary embodiments, the ancillary digital imaging receptor70may be adapted to move between a stored position and an imaging position, such as depicted in the example ofFIG. 19. The ancillary digital imaging receptor70may be adapted to move between the stored and imaging positions by rotation, pivoting, or other suitable forms or direction of movement.

When the system10is in use during the removal of a specimen, the ancillary digital imaging receptor70may be in a stored position out of the way of the procedure. In one example, such as depicted inFIG. 19, the ancillary imaging receptor70may be adjacent and substantially coplanar against the underside face of the patient table when in the stored position. In another example, the ancillary imaging receptor70may be positioned off to the side of the table20when in the stored position. In other examples, the ancillary imaging receptor70may be positioned in other suitable locations when in the stored position so as to allow for the removal of the biopsy specimen.

Likewise, when the system10is in use during the viewing of a specimen, the ancillary digital imaging receptor70may be in an imaging position such as shown inFIGS. 18-20so as to be suitably aligned with the x-ray source. In one example, as depicted inFIG. 19, the ancillary imaging receptor70may be moved down and/or laterally to be positioned in the imaging position for viewing a specimen.

In one embodiment, the ancillary digital imaging receptor70may be adjustably secured by a pivotable attaching device75, as seen in at leastFIG. 19. However, other types of adjustable securing devices75may be used individually or in conjunction with each other, including, but not limited to: sliding tracks, swivel connections, pivotable connections, etc. In some examples, a device for adjustably securing the ancillary digital imaging receptor70may include one or more preset positions, such as the stored position and/or the imaging position, where the ancillary digital imaging receptor70may lock into place. The preset positions may facilitate the functioning of the ancillary digital imaging receptor70by aligning the receptor with the x-ray source60.

Although an individual may move the digital imaging receptor70into position in some embodiments, in other embodiments the ancillary digital imaging receptor70may be automatically positioned by associating the receptor70, or a portion thereof, with an automated positioning apparatus77, such as depicted inFIG. 18. An automated apparatus77may employ any embodiment of a receptor70, or alternatively, an automated apparatus77may employ just a portion of such an embodiment. For example, any of the receptors70shown and described herein may be attached to or associated with a robotic arm or other automated movement mechanism designed and/or programmed to effect receptor70positioning.

While certain exemplary embodiments of the present invention are described in detail above, the scope of the invention is not to be considered limited by such disclosure, and modifications are possible without departing from the spirit of the invention as evidenced by the following claims.