Abstract:
A biopsy probe for the collection of at least one soft tissue sample from a surgical-patient. The biopsy probe has a handle, having a distal end and a proximal end, for holding the probe. The probe further includes an elongated needle, located at the distal end of the handle. The needle has a sharpened distal end for piercing tissue and a bowl for receiving a tissue mass. The probe has a cutter for severing the tissue mass received in the bowl, and at least one tissue marker element to apply a mark to the exterior of the tissue so the radial orientation of the tissue can later be determined.

Description:
FIELD OF THE INVENTION 
     The present invention relates, in general, to biopsy instruments and methods of taking biopsies and, more particularly, to a percutaneous biopsy instrument containing an element adapted to mark a biopsy specimen prior to harvesting. 
     BACKGROUND OF THE INVENTION 
     The diagnosis and treatment of patients with cancerous tumors, pre-malignant conditions, and other disorders has long been an area of intense investigation. Noninvasive methods for examining tissue are palpation, X-ray, MRI, CT, and ultrasound imaging. When the physician suspects that a tissue may contain cancerous cells, a biopsy may be done either in an open procedure or in a percutaneous procedure. 
     For an open procedure, a scalpel is used by the surgeon to create a large incision in the tissue in order to provide direct viewing and access to the tissue mass of interest. Removal of the entire mass (excisional biopsy) or a part of the mass (incisional biopsy) is done. The excised mass of tissue is examined by the surgeon and then by a pathologist using more precise means to determine if all of the cancerous tissue has been excised. Through direct visualization and palpation the surgeon inspects the excised tissue mass to determine if cancer may exist at the edges of the excised mass. This is followed by the pathologist examining the mass using various techniques to determine if cancer cells are near the edge. To aid the pathologist the surgeon typically identifies the in situ orientation of the mass. This is done by inserting sutures at predetermined locations around the edges of the mass or by marking the edges of the mass with a stain, commonly India ink. If the pathologist then determines that there are cancer cells near one of the edges of the mass the pathologist can direct the surgeon to remove additional tissue from the patient in the area corresponding to the locators marked on the original tissue specimen. 
     For a percutaneous biopsy, a needle-like instrument is used. An example of a percutaneous biopsy device is the Mammotome™ biopsy system available from Ethicon Endo-Surgery, Inc., Cincinnati, Ohio. Mammotome works through a very small incision to access the tissue mass of interest and to obtain a tissue sample for examination and analysis. Multiple tissue specimens can be removed through a single insertion. The Mammotome biopsy probe typically is rotated about its longitudinal axis at predetermined increments to a new position as each specimen is harvested. Using this technique multiple adjacent tissue samples can be removed. Multiple 360 degree revolutions of the probe may be necessary to remove all of the desired tissue. 
     The advantages of the percutaneous method as compared to the open method are significant: less recovery time for the patient, less pain, less surgical time, lower cost, less risk of injury to adjacent bodily tissues such as nerves, and less disfigurement of the patient&#39;s anatomy. However, since the tissue mass is removed in multiple pieces, reconstruction of the mass from the harvested pieces is challenging. With great care the clinician can identify and document the order of each specimen&#39;s removal. And, because each tissue specimen is cylindrical in geometry and the distal to proximal end orientation is maintained during the specimen harvesting procedure, the clinician can maintain the distal to proximal end orientation of the specimens during post biopsy analysis. What the clinician does not know, however, is the radial orientation of the cylindrical biopsy specimen as it was prior to being harvested. Once the specimen is severed and captured by Mammotome&#39;s rotating cutter, in situ radial orientation is lost. Lack of this information makes it difficult to accurately reconstruct the tissue mass to determine if all cancerous cells have been harvested. Without radial orientation information, especially on the last biopsy specimens to be taken since they typically represent the outer perimeter of the entire tissue mass harvested, it&#39;s difficult for the pathologist to direct the clinician back to a specific area at the biopsy site if additional tissue is needed. 
     Radial orientation of other biopsy devices has also been a problem. In the prior art, PCT application number WO0012010 to Sirimanne et al describes a percutaneous tissue biopsy device incorporating a rotating wire which produces a helical cut. A tissue mass can be removed through a comparatively small opening and readily reconstructed. Unfortunately, however, the in situ orientation of the tissue mass is lost once removed from the patient. U.S. Pat. No. 6,036,698 to Fawzi et al describes a percutaneous tissue biopsy device using an expandable ring cutter. A relatively large tissue specimen can be removed through a comparatively small device. Again no means is described in this invention for marking the in situ orientation of the tissue specimen and, therefor, orientation is lost upon removal from the patient. U.S. Pat. No. 5,578,030 to Levin describes a biopsy needle with a cauterization feature. In this invention tissue specimens are harvested through a stylet contained within a biopsy needle. Once the specimen is taken, the biopsy needle is energized to cauterize the wound caused by the taking of the tissue specimen. This invention features a means for insulating the excised tissue specimen from the cauterizing heat. No means is described for marking in situ orientation of the specimen. Similarly, U.S. Pat. No. 5,295,990 to Levin describes a tissue biopsy device with pivoting cutting jaws. Once the tissue specimen is severed, by closing the cutting jaws, the jaws are energized with electric current to cauterize tissue surrounding the jaws. An insulating material covers the inside of the jaws where the tissue specimen resides to protect the specimen from the cauterization heat. Again, no means are described to mark the specimen to identify orientation. 
     What is needed is a percutaneous biopsy instrument incorporating an element for marking the orientation of each specimen in situ, prior to harvesting and examination. 
     SUMMARY OF THE INVENTION 
     A biopsy probe for the collection of at least one soft tissue sample from a surgical patient. The biopsy probe has a handle, having a distal end and a proximal end, for holding the probe. The probe further includes an elongated needle, located at the distal end of the handle. The needle has a sharpened distal end for piercing tissue and a bowl for receiving a tissue mass. The probe has a cutter for severing the tissue mass received in the bowl, and at least one tissue marker element to apply a mark to the exterior of the tissue so the radial orientation of the tissue can later be determined. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to organization and methods of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings in which: 
     FIG. 1 is an isometric view of a biopsy apparatus, showing the biopsy probe of FIG. 2 assembled to a handle, and schematic representations of a control module and energy unit; 
     FIG. 2 is an isometric view of the biopsy probe of the present invention and handle shown separated; 
     FIG. 3 is an isometric view of the distal end of the biopsy probe of FIG. 2, illustrating the marker element of the present invention; 
     FIG. 4 is a longitudinal section view of the distal end of the biopsy probe illustrated in FIG. 3; 
     FIG. 5 is a cross sectional view taken along line  5 — 5  of FIG. 4; 
     FIG. 6 is an enlarged fragmentary cross sectional view taken from FIG. 4 showing details of the marker element of the present invention; 
     FIG. 7 is an enlarged fragmentary cross sectional view similar to FIG. 6, illustrating a second, alternate embodiment of the marker element; 
     FIG. 8 is an enlarged fragmentary cross sectional view similar to FIG.6, illustrating a third, alternate embodiment of the marker element; 
     FIG. 9 is an isometric view of the distal end of the biopsy probe of FIG. 2, illustrating multiple marker elements; 
     FIG. 10 is a longitudinal section view of the distal end of the biopsy probe of FIG. 9; 
     FIG. 11 is a longitudinal section view of the biopsy probe of the present invention, similarly illustrated in FIG. 4, showing the cutter in its most distal position and showing the biopsy probe inserted into the targeted tissue mass; 
     FIG. 12 is a longitudinal section view of the biopsy probe similar to FIG. 11, illustrating the retraction of the cutter in preparation for taking a tissue sample; 
     FIG. 13 is a longitudinal section view of the biopsy probe similar to FIG. 11, illustrating the prolapse of tissue into the tissue bowl following the application of vacuum and illustrating the tissue making contact with the marker element and the marker element being energized to mark the tissue specimen; 
     FIG. 14 is a longitudinal section view of the biopsy probe similar to FIG. 11, illustrating the simultaneous rotation and distal advancement of the cutter and the marked, severed tissue specimen contained within the cutter; 
     FIG. 15 is a cross sectional view taken along line  15 — 15  of FIG. 13; 
     FIG. 16 is a cross sectional view similar to FIG. 15, illustrating a first tissue specimen having been cut, the cutter retracted, and the specimen removed; 
     FIG. 17 is an isometric view of the first tissue specimen illustrating a mark on the perimeter of the specimen; 
     FIG. 18 is a cross sectional view similar to FIG. 15, illustrating that the biopsy probe has been rotated about its axis to take a second tissue sample; 
     FIG. 19 is an isometric view of the second tissue specimen again illustrating a mark on the perimeter of the specimen; 
     FIG. 20 is a cross sectional view similar to FIG. 15, illustrating the space remaining in the tissue mass after multiple tissue specimens have been harvested; 
     FIG. 21 illustrates the reconstruction of the harvested tissue mass from the multiple specimens, and illustrates using the mark on each specimen to determine correct radial orientation of each specimen. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIG.  1  and FIG. 2 wherein like numerals indicate the same element throughout the views, there is shown a biopsy apparatus  10  made in accordance with the present invention. Many of the features of apparatus  10  are known to those skilled in the art, and indeed many of the known features are described in U.S. Pat. No. 6,086,544 issued to Hibner et al which is hereby incorporated herein by reference. Biopsy apparatus  10  is comprised of a handle  12 , which operably connects to probe  14 . A suitable handle  12  is commercially available as part no. HHHC1, and a suitable probe  14  is commercially available as part no. MHH11, from Ethicon Endo-Surgery, Inc., Cincinnati, Ohio. Needle  20  is located at the distal end of probe  14 . At the proximal end of probe  14  is probe driver  22 . Contained within the housing of probe driver  22  are gears (not shown) which effect rotation and translation of cutter  24 . Control module  18  is operatively connected to handle  12  and contains motors that control rotation and translation of cutter  24  located in probe  14 . Control module  18  also contains a vacuum pump and reservoir that is fluidly connected to probe  14 . A suitable control module is available commercially as part no. SCM12, from Ethicon Endo-Surgery, Inc., Cincinnati, Ohio. and is described in U.S. Pat. No. 6,120,462 to Hibner et al, which is hereby incorporated herein by reference. Energy unit  16  is operably connected to probe  14  and is used to energize marker element  26  (see FIG.  3 ), which will be described in detail later. 
     FIG. 3, FIG.  4  and FIG. 5 illustrate the distal end of needle  20 . In the preferred embodiment needle  20  is made of electrically conductive materials such as, for example, stainless steel. Needle  20  is comprised of an upper lumen  30  and a lower lumen  32 . Vacuum holes  36  are located in the bottom of bowl  34  and allow for fluid communication between bowl  34 , located in upper lumen  30 , and lower lumen  32 . In the preferred embodiment two parallel rows of vacuum holes are located in bowl bottom  38 , straddling the center axis of upper lumen  30 . Cutter  24  is a tubular structure with a sharpened distal end  25  and can rotate and translate within upper lumen  30 . At the most distal end of needle  20  is fixedly attached piercing element  28 . 
     To better understand the present invention, a brief description of the process of taking a biopsy sample from the breast follows. The process, including the novel elements of the present invention, is described in greater detail later: 
     Images of the breast are taken, typically using x-ray or ultrasound, to locate the suspect lesion in the breast. Needle  20  is advanced into the lesion with bowl  34  placed at the location where the desired tissue specimen is to be harvested. Vacuum is applied to bowl  34  causing the prolapse of tissue against bowl bottom  38  and against marker element  26 . At this point marker element  26 , the focus of the present invention, is momentarily energized leaving a distinct mark on the surface of the tissue where it contacts. Cutter  24  rotates and is advanced distally through bowl  34  severing the tissue. Vacuum is terminated at bowl  34  and cutter  24  is retracted proximal carrying with it the severed tissue specimen. The specimen is retrieved at the proximal end of needle  20  by the clinician. The clinician may now rotate needle  20  about its axis and repeat the process to take additional samples if desired. 
     Referring again to FIGS. 3 through 5, within bowl bottom  38  at the base of bowl  34  is located marker element  26 . In the illustrated embodiment marker element  26  is located at the proximal end of bowl  34  between parallel rows of vacuum holes  36 . However, it could be located anywhere along the bowl bottom  38 . 
     FIG. 6 illustrates in detail the preferred embodiment of marker element  26 . Marker hole  40  is located in bowl bottom  38 . Marker element  26  comprises insulator ring  42 , which is generally cylindrical with a hole through its center. Insulator ring  42  is made from any commonly available electrical insulating material such as, for example, ceramic and is fixedly attached within marker hole  40  by adhesive or mechanical means. Marker rod  44  is generally cylindrical and made of an electrically conductive material such as, for example, steel and is fixedly attached within the hole in insulator ring  42  by adhesive or mechanical means. First connector wire  46 , which is a commonly available electrically conductive wire with insulation, is connected at one end to marker rod  44  and at the other end to energy unit  16  (see FIG.  1 ). Entire marker element  26  is mounted flush with bowl bottom  38  so that it will not interfere with the travel of cutter  24  through bowl  34 . Second conductor wire  48 , an electrically conductive wire with insulation, is connected at one end to needle  20  (see FIG. 4) and at the other end to energy unit  16  (see FIG.  1 ). 
     In the preferred embodiment of this invention energy unit  16  is an RF generator, commonly known and available in the medical arts. Marker rod  44  is connected to energy unit  16  via first conductor wire  46  and acts as the positive or charged conductor while needle  20  is connected to energy unit  16  via second conductor wire  48  as a ground. This arrangement would be commonly known as bipolar. Hence, applying RF energy to marker element  26  will cauterize in a localized area at marker rod  44  any tissue in contact with marker rod  44  and needle  20 , leaving a visible, distinct mark. 
     It would be evident to one skilled in the art that the arrangement just described could alternately be configured as monopolar by removing second conductor wire  48  from needle  20  and instead attaching second conductor wire  48  between energy unit  16  and the body of the patient. The patient&#39;s body is now a ground. Because needle  20  is no longer required to be electrically conductive, needle  20  can be fabricated from a non-electrically conductive material such as, for example, thermoplastic. This is very important when the biopsy instrument is used in some imaging environments such as MRI. 
     FIG. 7 illustrates a second, alternate embodiment of the present invention. Second alternate marker element  27  comprises insulator ring  42 , fixedly attached within second marker hole  41  in second bowl bottom  39 . Heater housing  56 , generally cylindrical in shape with a counter bore along its center axis, is made of a thermally conductive material and is fixedly attached within the hole in insulator ring  42 . Heater  50  is made of an electrically resistive wire material such as, for example, tungsten and is fixedly attached within heater housing  56  using commonly available potting materials such as, for example, epoxy. Third conductor wire  52  and fourth conductor wire  54  are electrically conductive insulated wires and electrically connect the ends of heater  50  to an energy unit, similar to that of energy unit  16 . In this alternate embodiment the energy unit is an electric current source capable of supplying controlled electric current to heater  50  in second marker element  27 . Hence, tissue coming into contact with heater housing  56 , which is made hot when current is supplied to heater  50 , will be cauterized, leaving a visible, distinct mark in the localized area of heater housing  50 . It should be evident that in this embodiment needle  20  may be constructed of an electrically conductive or non-electrically conductive material. 
     FIG. 8 illustrates a third, alternate embodiment of the present invention. Third alternate marker element  29  comprises hole  61  pierced through third bowl bottom  43  and the perimeter surface of hole  61  is extruded to create flange  58 . Tube  60  is fixedly attached to flange  58  using commonly available adhesives. Tube  60  may be made of a flexible material such as, for example, vinyl. The other end of tube  60  is attached to a unit which preferably is a fluid reservoir such as, for example, a syringe. Tissue staining fluid such as a dye, for example, India ink, commonly used in the medical arts, may be placed in the fluid reservoir. Tube  60  fluidly connects the fluid reservoir to hole  61  in third bowl bottom  43 . Hence, staining fluid may be injected by a syringe through tube  60  and through hole  61  leaving a visible, distinct mark on tissue in contact with hole  61 . 
     Referring now to FIG.  9  and FIG. 10, multiple marker elements may be incorporated into needle  20 . Up to this point the use of only a single marker element  26  to make a single mark on the tissue specimen, as a guide to in situ orientation, has been discussed. FIGS. 9 &amp; 10 illustrate first, second, and third marker elements  62 ,  64 , and  66  respectively. The marker elements may be constructed as described previously. Each marker element may be connected individually to energy unit  16 , allowing first marker element  62 , second marker element  64 , and third marker element  66  to be controlled individually. Energizing various combinations of marker elements to mark each specimen could give the clinician more information on each tissue specimen, based on the number and spacing of the marks. For example, different combinations of marker elements being activated to mark each specimen would provide information to the clinician not only identifying orientation of each specimen, but could also provide sequence numbering on the specimen. For example, the first tissue specimen may be identified by one mark, caused by the activation of only the most proximal first marker element  62 . The second specimen may be identified by two marks, created by activating first marker element  62  and adjacent second marker element  64 . The third specimen may be identified by activating first, second, and third marker elements  62 ,  64 , and  66  respectively. The fourth specimen may be identified by activating first marker element  62  and third marker element  66 , the clinician being required to note the spacing between the marks so as not to confuse specimen four with specimen two. The more marker elements available, the more mark combinations, the more specimens that can be identified. Ideally, mark combinations would be computer controlled at energy unit  16 . 
     FIGS. 11 through 14 illustrate generally the steps necessary to harvest a tissue specimen utilizing the biopsy apparatus of the present invention. Referring to FIG. 11, needle  20  is advanced into lesion  68  with cutter  24  in its most distal position to close off bowl  34  to prevent snagging and tearing of tissue during linear movement of needle  20 . Referring now to FIG. 12, after needle  20  has been positioned at the desired location in lesion  68  cutter  24  is retracted proximally. In FIG. 13, the vacuum source in control module  18  (see FIG. 1) is activated. Vacuum is communicated from control module  18  via flexible tubing to a fitting on lower lumen  32  in needle  20 . As a result, a region of low pressure is created in lower lumen  32 , which is in fluid communication via vacuum holes  36 , with bowl  34  in upper lumen  30 . Hence, the vacuum facilitates the prolapse of tissue against bowl bottom  38  in bowl  34 . Once the tissue is fully prolapsed into bowl  34 , marker element  26  is momentarily activated, leaving a mark  70  on the tissue, identifying the surface of the tissue that is in contact with bowl bottom  38 . Referring to FIG. 14, motors in control module  18  communicate with gears in probe driver  22  via flexible cables to effect rotation and distal translation of cutter  24  through bowl  34 , severing the tissue. Vacuum is then terminated and cutter  24  is retracted to the proximal end of needle  20  where the marked tissue specimen is retrieved by the clinician. 
     FIGS. 15 through 20 illustrate a procedure whereby multiple tissue specimens may be marked and acquired by rotating needle  20  to different angular positions. FIG. 15 is a cross sectional view taken along line  15 — 15  of FIG. 13, and shows needle  20  angularity positioned with bowl  34  in an upright or 12 o&#39;clock position within lesion  68 . Vacuum has been initiated through lower lumen  32  which effects the prolapse of tissue into bowl  34 , pulling tissue into contact with marker element  26 . Marker element  26  is momentarily activated, leaving a mark  70  on the surface of the tissue in contact with marker element  26 . FIG. 16 is a cross sectional view similar to FIG. 15, whereas a first tissue specimen  72  has been cut, vacuum terminated, cutter  24  retracted, and first tissue specimen  72  removed. FIG. 17 illustrates first tissue specimen  72  with identifying mark  70  on the outer surface indicating the surface of the specimen that was in contact with marker element  26  in situ. FIG. 18 is a cross sectional view similar to FIG. 15, wherein the clinician has elected to rotate needle  20  approximately 90 degrees to the 9 o&#39;clock position. Again, vacuum is applied, marker element  26  is momentarily activated, and second tissue specimen  74  is cut. FIG. 19 illustrates second tissue specimen  74  with identifying mark  70  on the outer surface indicating the surface of the specimen that was in contact with marker element  26  in situ. The clinician would continue to rotate needle  20  to different angular positions and repeat this process until the desired number of tissue specimens is taken. FIG. 20 is a cross sectional view similar to FIG. 15 illustrating the cavity remaining in lesion  68  after multiple tissue specimens have been removed. 
     FIG. 21 illustrates the reconstruction of the tissue mass removed in multiple pieces, showing a mark on each tissue specimen used to identify the proper radial orientation of the specimen as it was in situ. Lesion  68  is shown to illustrate the relationship of each specimen to the cavity resulting from the removal of multiple specimens. First tissue specimen  72  is shown at the 12 o&#39;clock position with identifying mark  70  properly oriented to the center of lesion  68 . Second tissue specimen  74  is shown at the 9 o&#39;clock position with identifying mark  70  properly oriented again to the center of lesion  68 . Subsequent tissue specimens are illustrated to show their orientations relative to lesion  68 . 
     It should be noted that if multiple marker elements  26  are employed in the construction of needle  20  as discussed previously, multiple identifying marks  70  may be evident in FIGS. 17 and 19, provding to the clinician not only radial orientation information on each specimen but also information on the sequence in which each specimen was removed. 
     While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.