Abstract:
A system includes a grid-like, breast-receiving pressure plate having a polygonal opening. A prism is configured to match the polygonal opening. The prism includes a first conduit that has a zero first offset from the prism center and a second conduit that has a second offset from the prism center.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 14/275,383 filed May 12, 2014, now U.S. Pat. No. 9,700,349, which is a continuation of U.S. patent application Ser. No. 13/766,287 filed Feb. 13, 2013, now U.S. Pat. No. 8,758,265, which is a continuation of U.S. patent application Ser. No. 12/779,735 filed May 13, 2010, now U.S. Pat. No. 8,398,565, which is a continuation of U.S. patent application Ser. No. 11/981,006 filed Oct. 31, 2007, now U.S. Pat. No. 7,744,543, which is a divisional of U.S. patent application Ser. No. 11/298,154 filed Dec. 9, 2005, now U.S. Pat. No. 7,740,593, all of which are incorporated herein in their entirety by reference and from which priority is claimed. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates generally to the field of medical devices and methods. In particular, the invention relates to devices and methods for placing a surgical device, such as a biopsy device, in a desired location in relation to a patient during a biopsy procedure. 
       BACKGROUND OF THE INVENTION 
       [0003]    In diagnosing and treating certain medical conditions, it is often desirable to perform a biopsy, in which a specimen or sample of tissue is removed for pathological examination, tests and analysis. As is known, obtaining a tissue sample by biopsy and the subsequent examination are typically employed in the diagnosis of cancers and other malignant tumors, or to confirm that a suspected lesion or tumor is not malignant. Examination of tissue samples taken by biopsy is of particular significance in the diagnosis and treatment of breast cancer. 
         [0004]    Magnetic resonance imaging (MRI) is often used to locate the site within a breast where a potentially cancerous lesion or tumor is located. Interventional MRI is the magnetic resonance imaging technique (often involving real time imaging) that allows a surgeon to perform MRI-guided tissue biopsy or surgery. One application of interventional MRI is to guide a surgeon during a biopsy or surgical operation on one or both of the breasts of a female patient. 
         [0005]    Interventional MRI procedures typically require a magnetic resonance signal detection coil which has large openings so that the surgeon can have access to the surgical site through the coil with the biopsy device or other surgical devices. The MRI device may also include compression plates to compress the breast. Compression plates contain needle guide holes to allow for proper placement of a needle during a needle biopsy or larger windows configured to hold guide blocks. Guide blocks have block bodies with needle guide holes or with larger openings to allow access for larger biopsy devices. The guide blocks assist the physician with proper placement and stabilization of the biopsy device during a biopsy procedure. 
         [0006]    The compression plates are secured to the housing of the signal detection coil. Markers, such as Vitamin E Capsules, which are highly visible under MRI device are placed on the compression plates and the position of the markers relative to the suspect tissue is measured using the magnetic resonance images. The proper window of the compression plate is then determined by finding the window in the compression plate which is closest to the desired entry point. 
         [0007]    For larger biopsy devices the guide blocks are usually cube-shaped and contain about nine circular openings spaced in three rows of three. Due to the configuration of the openings in the guide block and the large size of some biopsy devices it is often difficult to precisely reach the desired tissue location. Present guide blocks for larger biopsy devices do not allow for access to every area of tissue directly behind the block. Thus, there is need in the art for improved guide blocks which allow access to all areas of tissue directly behind the block. 
       SUMMARY OF THE INVENTION 
       [0008]    This invention relates to placement of surgical devices during biopsy procedures and in particular to devices and methods for placement of a biopsy device during a breast biopsy. 
         [0009]    In one embodiment of the present invention a guide block has a body with a proximal face, a distal face and a longitudinal axis extending between the proximal and distal faces. The guide block has four passageways which are configured to slidably receive a surgical device, such as a biopsy device. The body of the guide block is configured to fit within a grid on the compression plate of a magnetic resonance imaging (MRI) device. 
         [0010]    The four passageways extend longitudinally between the proximal and distal faces of the block and are parallel to the longitudinal axis. The first passageway is centrally disposed. The second passageway is located vertical or horizontal to the first passageway. The third passageway is located diagonal to the first and has a longitudinal opening along its length which is in fluid communication with the opening in the first passageway. The fourth passageway is located diagonal to the first passageway and on an opposite side of the body from the third passageway. The configuration of the passageways allows for all tissue directly behind the guide block to be accessed by rotating the guide block. 
         [0011]    A method embodying features of the invention includes providing a guide block having a body with four passageways which are configured within the body as described above and inserting the guide block into a grid opening of a magnetic resonance imaging device nearest to the suspect tissue and orienting the block to provide access to the desired location in a patient. 
         [0012]    In an alternative embodiment of the invention a guide block has a block body with a proximal face, a distal face, and a longitudinal axis extending between the proximal and distal faces. The guide block has at least one passageway disposed within the body which is open along the length thereof and which extends between the proximal and distal faces and are not parallel to the longitudinal axis. The configuration of the at least one passageway allows for access to tissue located outside of the exterior border of the compression plate. 
         [0013]    A method embodying features of the invention includes providing a guide block having a body with a proximal face, a distal face, and a longitudinal axis extending between the proximal and distal faces. The guide block has at least one passageway disposed within the body which extends between the proximal and distal faces and which is not parallel to the longitudinal axis. The method further includes inserting the guide block into a grid opening of an MRI nearest to the suspect tissue and selecting the orientation of the block  10  to provide access to the desired location in the patient. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a front elevational view of a device embodying features of the invention. 
           [0015]      FIG. 2  is a rear elevational view of a device embodying features of the invention. 
           [0016]      FIG. 3  is a side elevational view of a device embodying features of the invention. 
           [0017]      FIG. 4  is a side elevational view of a device embodying features of the invention. 
           [0018]      FIG. 5  is a longitudinal cross sectional view of the device taken along lines  5 - 5  in  FIG. 2 . 
           [0019]      FIG. 6  is a longitudinal cross sectional view of the device taken along lines  6 - 6  in  FIG. 2 . 
           [0020]      FIG. 7  is a elevational view of a magnetic resonance imaging device having compression plates with grids configured to receive devices embodying features of the invention. 
           [0021]      FIG. 8  is a front elevational view of a device embodying features of the invention. 
           [0022]      FIG. 9  is a rear elevational view of a device embodying features of the invention. 
           [0023]      FIG. 10  is a longitudinal cross sectional view of a device shown in  FIGS. 8 and 9 . 
           [0024]      FIG. 11  is a side view of a device embodying features of the invention within the grid of a compression plate. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]      FIGS. 1-6  are elevational views of devices embodying features of the invention. A device embodying features of the invention includes a guide block  10  having a body  12  with a proximal face  14 , a distal face  16  and a longitudinal axis  18  extending between the proximal  14  and distal  16  faces. The guide block  10  has four passageways  20  which extend longitudinally between the proximal  14  and distal  16  faces of the guide block  10  and which are parallel to the longitudinal axis  18 . Each passageway  20  of the guide block  10  is configured to slidably receive a surgical device, such as the biopsy device in U.S. Pat. No. 6,454,727 assigned to the assignee of the present invention. Preferably the passageways  20  are cylindrically shaped. 
         [0026]    The first passageway  22  is centrally disposed. The second passageway  24  is located vertical or horizontal to the first passageway  22  and parallel to the longitudinal axis. The third passageway  26  is located diagonal to the first passageway  22 , and is parallel to the longitudinal axis. The third passageway also has a longitudinal opening along its length which is in fluid communication with the opening in the first passageway  22 . The fourth passageway  28 , is parallel to the longitudinal axis, and is located diagonal to the first passageway  22  and in an opposite side of the body  12  from the diagonal location of the third passageway  26 . Two suitable configurations of the passageways  20  within the guide block  10 , shown in  FIGS. 1 and 2 , are mirror images of one another. 
         [0027]    The guide block  10  is configured to be used in conjunction with a locating or imaging devices such as a magnetic resonance imaging (MRI) device. An example of an MRI breast coil and grid device is the Invivo 7 channel breast biopsy array 800239 in  FIG. 7  (photo obtained from www.mridevices.com/products/CoilProduct Detail.aspx?ID=43). A MRI device  30  used to detect suspect tissue in breasts has a detection coil  32  with large openings  34 . The MRI device  30  also includes compression plates  36  to compress the breast. The compression plates  36  are secured to the housing of the detection coil  32  and include grid  38  with grid openings  40  so that the surgeon can have access to the surgical site through the coil  32  with the biopsy device or other surgical devices. The grid openings  40  have four sides  42  and are configured to receive the guide blocks  10  and hold them in place. Preferably the guide block  10  has a proximal face  14  with four equal sides  44 . When the guide block  10  is placed into the grid opening  40  any one of the four sides  44  of the proximal face  14  of the guide block may align with any one of the four sides  42  of a grid opening  40  to secure the block within the grid  38 . 
         [0028]    The location of the passageways  20  within the block  10  allows a biopsy device to gain access to all areas of tissue behind the block  10 . By rotating the block before placing it within the grid opening  40 , each area of tissue behind the block  10  will, at some point, be accessible through one of the four passageways  20 . 
         [0029]    In some embodiments the proximal face  14  has a larger surface area than the surface area of the distal face  16  and forms a radially projecting shoulder  46  which prevents the block from advancing too far past the grid opening  40 . The shoulder  46  extends about 0.02 inches to about 0.06 inches from the outside wall of the body. 
         [0030]    In one embodiment of the device each side  44  of the proximal face  14  of the device is about 0.4 inches to about 1.3 inches long, typically about 0.9 inches long. In this embodiment the center of the first passageway  22  is about 0.2 inches to about 0.6 inches from each side  44  of the proximal face, typically about 0.4 inches from each side  44 . The center of the second passageway  24  is about to 0.1 inches about 0.35 inches from the center of the first passageway  22 , typically about 0.2 inches away from the center of the first passageway  22 . The center of the third passageway  26  is about 0.1 inches to about 0.25 inches, typically about 0.15 inches away from the center of the first passageway  22 . The center of the fourth passageway  28  is about 0.15 inches to about 0.5 inches away from the center of the first guide passageway  22 , typically about 0.3 inches. The length of block  10  is about 0.5 to about 0.9, typically about 0.8 inches. 
         [0031]    In one embodiment the guide block  10  includes at least one tab  48  on the perimeter of the body which extends between the proximal and distal faces and which has a distal portion near the distal face of the block with a raised area  50 . The tabs  48  are configured to allow the raised area  50  to bend inward toward the body when placing the block within a grid opening  40 . Once in the opening the raised area  50  extends radially outward and presses against the sides  42  of the grid opening  40  as a means to maintain its position. 
         [0032]    In some embodiments the tab is about 0.05 inches to about 0.15 inches wide, preferably about 0.10 inches wide. The tabs range in length from about 0.25 to about 0.8 inches long. In some embodiments of the invention at least one tab  48  is about 0.05 to about 0.2 inches wide, preferably about 0.15 inches wide. 
         [0033]    The guide block  10  may be formed from a plastic such as MAKROLON®, a polycarbonate from Bayer Material Sciences a division of Bayer AG. 
         [0034]    A method embodying features of the invention includes providing a guide block  10  having a body  12  with four passageways  20  which are configured within the body. The first passageway  22  is centrally disposed. The second passageway  24  is located vertical or horizontal to the first passageway  22  and parallel to the longitudinal axis. The third passageway  26  is located diagonal to the first passageway  22 , and is parallel to the longitudinal axis. The third passageway also has a longitudinal opening along its length which is in fluid communication with the opening in the first passageway  22 . The fourth passageway  28 , is parallel to the longitudinal axis, and is located diagonal to the first passageway  22  and in on opposite side of the body  12  from the diagonal location of the third passageway  26 . The method further includes inserting the guide block into a grid opening  40  of an MRI device  30  nearest to the suspect tissue and selecting the orientation of the block  10  to provide access to the desired location in patient. 
         [0035]    In some methods embodying features of the invention an imaging device configured to locate suspect tissue is provided to locate the suspect tissue. Preferably the imaging device is magnetic resonance imaging  30 . 
         [0036]    An alternative embodiment of the invention illustrated in  FIGS. 8-11  include a guide block  52  having a body  54  with a proximal face  56 , a distal face  58 , and a longitudinal axis  60  extending between the proximal face  56  and distal face  58 . The guide block  52  has at least one passageway  62  disposed within the body which extends between the proximal and distal faces and are not parallel to the longitudinal axis. This embodiment provides access to tissue located outside of the exterior border of the grid  64  of the compression plate  66 . 
         [0037]    A method embodying features of the invention includes providing a guide block  52  having a body  54  with a proximal face  56  a distal face  58 , and a longitudinal axis  60  extending between the proximal and distal faces. The guide block  52  has at least one passageway  62  disposed within the body  54  which extends between the proximal  56  and distal faces  58  and which is not parallel to the longitudinal axis  60 . The method further includes inserting the guide block  52  into a grid opening  68  of a compression plate  66  nearest to the suspect tissue and selecting the orientation of the block  52  to provide access to the desired location in the patient. 
         [0038]    While particular forms of the invention have been illustrated and described herein, it will be apparent that various modifications and improvements can be made to the invention. Moreover, individual features of embodiments of the invention may be shown in some drawings and not in others, but those skilled in the art will recognize that individual features of one embodiment of the invention can be combined with any or all the features of another embodiment. Accordingly, it is not intended that the invention be limited to the specific embodiments illustrated. It is therefore intended that this invention be defined by the scope of the appended claims as broadly as the prior art will permit. 
         [0039]    Terms such as “element”, “member”, “component”, “device”, “means”, “portion”, “section”, “steps”, “means” and words of similar import when used herein shall not be construed as invoking the provisions of 35 U.S.C §112(6) unless the following claims expressly use the terms “means” or “step” followed by a particular function without reference to a specific structure or action. All patents and all patent applications referred to above are hereby incorporated by reference in their entirety.