Abstract:
An automated device for obtaining a tissue biopsy and delivering material to provide hemostatis, therapeutic agents or marker material is described. The device has an outer casing, a power source, a drive mechanism, an application chamber through which the biopsy mechanism, typically a cutting needle, passes through and an application channel. The cutting biopsy mechanism has a mechanical or electromechanical mechanism to rapidly fire a stylet with a biopsy trough into the intended tissue and then rapidly propel a biopsy cannula over the stylet to sever and retain tissue that has protruded into the biopsy trough. At least one application channel is formed by a tube centrically slipped over the biopsy cannula wall. To enable the collection of tissue specimens, the distal segment of the application channel forms a close fitting and concentric sheath around the biopsy cannula.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application makes reference to the following co-pending U.S. Patent Applications. The first application is U.S. App. No. 60/749,587, entitled “Automated Biopsy and Delivery” filed Dec. 13, 2005 and claims the benefit thereof. The second application is U.S. application Ser. No. 10/858,112, entitled “Biopsy and Delivery Device,” filed Jun. 1, 2004, now U.S. Pat. No. 7,169,114 from which this is a continuation-in-part. The entire disclosure and contents of the above applications are hereby incorporated by reference. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a device that automatically takes a biopsy or other sample of human or animal tissue and delivers a coagulant or other material to the biopsy incision track in order to plug the track and prevent bleeding, to provide a marker for future reference so that it may be located in a subsequent medical/surgical procedure or place a material or chemical to prevent seeding of cells from the biopsy site. 
     2. Related Art 
     In modern medical practice small tissue samples, known as biopsy specimens, are often removed from tumors, lesions, organs, muscles and other tissues of the body for histological evaluation and diagnosis. Such removal of tissue samples can be accomplished by open surgical technique (i.e., removal of a small sample of tissue through a small surgical incision using a local anesthetic), or through the use of a specialized biopsy instrument such as a biopsy needle. After the tissue samples have been removed, they are typically subjected to diagnostic tests or examinations such as a) gross and microscopic examination to determine cytology and/or histology, b) biochemical analyses to determine the presence or absence of chemical substances which indicate certain disease states, c) microbiological culturing to determine the presence of bacteria or other microbes, and/or d) other diagnostic procedures. The information obtained from these diagnostic tests and/or examinations can then be used to make or confirm diagnoses and/or to formulate treatment plans for the patient. 
     Special Considerations Relating to Biopsy and Plugging the Biopsy Track to Prevent Bleeding; Liver Biopsy 
     Excision biopsy of the liver has traditionally been the gold standard for assessing the extent of injury and determining prognosis in chronic viral hepatitis, non alcoholic steptohepatitis, fatty liver disease and liver cancer. A significant complication that frequently occurs is bleeding from the biopsy site. Significant hemorrhage occurs in 0.35 to 0.5% of all procedures while evidence of sub-clinical bleeding, as detectable by ultrasound 24 hours post biopsy, has been reported in up to 23% of patients. A smaller amount of surface bleeding is almost universal and is frequently associated with mild to moderate pain. 
     Excision biopsies from other organs, such as the lungs, also exhibit a relatively high complication rate due to hemorrhagic incidents and pneumothorax. Also with kidney biopsies and biopsies of other organs, perfuse bleeding is considered the most important complication. 
     In order to prevent bleeding resulting from the biopsy, it has been proposed to plug the biopsy channel with a hemostatic agent. A typical hemostatic agent can be Gelfoam (Pharnacia &amp; Upjohn), Avitene (Davol, Inc), FloSeal (Baxter International) or other similar agent. The treatment of a biopsy track with an injectable absorbable coagulant to facilitate homeostasis in conjunction with procuring a biopsy provides substantial advantages in comfort over external pressure methods or the insertion of a pledget of Gelfoam foam as described in U.S. Pat. No. 6,086,607, which must be inserted through a previously inserted catheter. The insertion of a catheter involves a longer procedure as well as the risk of the catheter shifting while the operator switches or disconnects from the aspiration biopsy syringe to the coagulant delivery syringe. In addition, the present invention also provides advantages over the insertion of an absorbable sponge material in a dry state with an applicator. A dry piece of sponge material must be cut to the particular size of the biopsy track and does not swell to fill the track until the blood has sufficiently saturated the sponge material which can take a significantly amount of time and provides inadequate local compression. 
     From Austrian Pat. No. 384,165, a biopsy needle device of the initially defined kind is known, with which the cannula has a curved partition wall towards the internal limitation of the cannula lumina. Therein, the partition wall does not reach immediately to the front end of the cannula so that the biopsy channel and the application channel communicate in the region of the tip of the cannula. The multi-lumen biopsy device according to Austrian Pat. No. 384,165 enables the collection of tissue and the application of substances plugging the puncture track in coordination with the puncturing procedure in one operating cycle, thus largely shortening the time of intervention. 
     U.S. Pat. No. 4,850,373 and related EP patents 243341 A, B1 etc., also describes a biopsy needle device having a two lumen cannula, a biopsy channel of constant cross section and one application channel. The application channel is formed by a tube eccentrically slipped over the biopsy channel wall. Furthermore, the biopsy channel is described as a non-circular tubular structure with its channel wall flattened in cross section such that an application channel is formed between the flattened side of the biopsy channel wall and the outer application tube. In addition, surface contact exists between the non-flattened side of the biopsy channel wall and the application tube. 
     A common surgical material used to control bleeding is Gelfoam®, which is supplied in either a powder form or as an implantable sponge. Sterile sponges, such as Gelfoam®, are prepared in dry sterile sheets that are used as packing material during surgery for control of bleeding. The sponge sheets are left in the surgical site after surgery to stop bleeding and are absorbed by the body in 1 to 6 weeks. A number of techniques have used these absorbable sterile sponge materials to plug a biopsy track to minimize or prevent bleeding. The absorbable sponge provides a mechanical blockage of the track, encourages clotting, and minimizes bleeding though the biopsy track. Despite the advantages of using absorbable sponge to plug a biopsy track this technique has not achieved widespread use because of difficulty in preparing and delivering the sponge material into the biopsy track. 
     One example of a biopsy wound closure device using an implantable sponge is described in U.S. Pat. No. 5,388,588. According to this patent, a circular sponge of an absorbable foam material is precut and inserted into a biopsy site by an applicator rod having the sponge positioned on the end. Once the sponge is implanted, the sponge absorbs blood and swells to fill the track preventing further bleeding at the biopsy site. However, the sponge is difficult to deliver and expands slowly once delivered. In addition, this delivery method can only deliver a sponge of a limited size that provides less local compression than desired and may incompletely fill the target site. Further, bleeding may continue along sections of the biopsy track where no sponge has been delivered. 
     Another example of a Gelfoam® inserting device to facilitate hemostasis is described in U.S. Pat. No. 6,086,607. According to this patent, a method of cutting a piece of Gelfoam® sponge from a sheet of the material, folding the strip to form a pledget with one end of different cross section than the other end, and inserting the pledget in an adapter to compress the pledget and for attachment to a syringe for delivery of the pledget to the tissue. The adapter is attached to a cannula that was previously inserted into the organ being biopsied and the Gelfoam® is inserted into the tissue through the cannula. 
     Cutting Needle Technique 
     As can be seen from Table 1, many cutting biopsy surgical appliances are currently known. Typically, the instrument consists of a long, thin probe, termed a stylet, within a close-fitting hollow needle, termed a cannula. The stylet and cannula are contained within or attached to a firing device that first projects the stylet into the tissue, followed immediately by the cannula. The stylet has a notch into which tissue will prolapse when the stylet enters the tissue. As the cannula slides over the stylet, a small piece of tissue is then severed from the organ mass and captured within the notch of the stylet. The instrument is then withdrawn and the piece of tissue removed from the stylet for evaluation. 
     
       
         
               
             
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Commercially Available Cutting/core Biopsy Devices 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Automated Cutting Devices 
                   
               
               
                 CR Bard 
                 Bard Max-Core Disposible Biopsy 
               
               
                   
                 System 
               
               
                 Cooke Inc 
                 Coaxial Quick-Core Biopsy Sets 
               
               
                 Boston Scientific 
                 ASAP ™ 
               
               
                 Semi-Automated Cutting Devices 
               
               
                 Allegiance Healthcare Corp 
                 Temno Biopsy System 
               
               
                 Avid Medical 
                 Spring loaded 
               
               
                 Ranfax Medical 
               
               
                 Remington Medical 
                 Remington Sharp Cut 
               
               
                 Cone Instruments 
                 TZ Spring loaded 
               
               
                   
               
             
          
         
       
     
     Griffith, U.S. Pat. No. 3,477,423, was one of the first to describe an economical and simplified, biopsy needle device in which a cannula is projected forward over the stylet with a recessed collection notch such that the tissue within the notch is severed and retained within the cannula for retrieval. Improvements over the years have lead to single handed, semi automatic driving devices as described by U.S. Pat. No. 4,944,308, U.S. Pat. No. 5,368,045 and U.S. Pat. No. 5,951,489. 
     Special Considerations Relating to Biopsy and Delivering a Marker Material: Breast Biopsy 
     Breast cancer is presently the most common cancer in women and is the second leading cause of cancer deaths in women. Periodic physical and radiographic examination of the breasts (mammography) is important for early detection of potentially cancerous lesions in women over 40 years of age. In mammography, the breast is compressed between two plates while specialized x-ray images are taken. If an abnormal mass in the breast is found by physical examination or mammography, ultrasound may be used to determine whether the mass is a solid tumor or a fluid filled cyst. Cystic lesions are generally benign and the diagnosis of a cystic lesion is often confirmed by needle aspiration of fluid from the interior of the cyst and immediate diagnosis. However, solid masses are usually subjected to some type of tissue biopsy to determine if the mass is cancerous. This determination requires that the tissue be processed which may require 24 to 48 hours. 
     Therefore in order to locate the site of the biopsy and cancerous tissue for removal or radiographic treatment at a subsequent procedure, the site is marked, either externally or internally, with a biopsy site marker. Various types of biopsy site markers have been known in the prior art. U.S. Pat. No. 2,192,270 (Carswell, Jr.) and U.S. Pat. No. 5,147,307 (Gluck) describes externally applied markers. Additionally, the prior surgical procedures have included radiographically visible markers that may be introduced into the biopsy site such as marker wires that are inserted through the biopsy needle after a tissue sample is removed and are thereafter allowed to remain protruding from the patient&#39;s body. U.S. Pat. No. 6,161,034 (Burbank) describes various chemical preparations and methods for marking biopsy sites which remain present and detectable for up to 5 to 8 months from the initial biopsy. A method for simultaneously taking the biopsy sample and delivering the marker material is not described. 
     In co-pending application U.S. patent application Ser. No. 10/858,112 (Krause) for a “Biopsy and Delivery Device”, filed Jun. 1, 2004, the forgoing problems were overcome. This application teaches the combination of the multi lumen, concentric needle device providing an assembly for obtaining the biopsy and an application channel with a syringe for delivering the application material using a mechanized delivery system. The prior art does not describe the combination of a cutting needle biopsy device with a syringe application device for delivery of the application material and a device which automatically takes the biopsy and delivers the application material. 
     The present invention, as described herein, provides a device which facilitates the means to take the biopsy specimen and deliver a hemostatic agent to minimize the bleeding from the biopsy tract. The invention describes an electro-mechanical device to accomplish the procedure. Other mechanisms such as pneumatic, hydraulic, magnetic and electrical could also be used to perform the same tasks as known by those skilled in the art. 
     SUMMARY OF THE INVENTION 
     The present invention provides a fully automated biopsy device with a view to enabling the collection of tissue specimens for biopsy and to apply auxiliary substances directly in the site of the puncture without tissue specimens getting into the application cannula, thus obstructing the same, or having to change instrumentation. Using the invention the clinician, using customary percutaneous biopsy technique, inserts the tip of the biopsy needle into the liver, or subject organ or organ, activates the device that automatically takes a biopsy and then delivers the coagulant or other material into the biopsy track. 
     The disclosed device uses a syringe tube to which is attached to an application channel formed by a tube of varying or constant cross section slipped over the biopsy mechanism channel wall. The biopsy mechanism is typically a commercially available spring action or core biopsy device. The stylet and cannula of the biopsy mechanism is typically positioned through the plunger of the coagulant syringe with the biopsy needle passing through the inner end of the plunger, the seal, coagulant chamber and the application channel. The application channel can also contain separate channels for fiber optic cables for the transmission of light or laser energy used in the photo initiation of delivered material. 
     Using commercially available biopsy equipment, a biopsy is achieved according to the invention in that after the tissue specimen is collected in the biopsy channel of the biopsy needle, the inner tube containing the tissue specimen is retracted within the concentric outer application tube thus allowing the application material to be injected into the biopsy track without obstruction. After obtaining a biopsy, the biopsy syringe is retracted within the application syringe plunger that is depressed by which the application material is expelled from the application chamber into the biopsy site. This may be facilitated by a placing the biopsy device in another device according to the invention that causes the translations and movements of the parts of the fore mentioned biopsy device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of the automated biopsy device in accordance with an embodiment of the present invention; 
         FIG. 2  is a cutaway view of the interior of the biopsy device of  FIG. 1  accordance with an embodiment of the present invention; 
         FIG. 3  is a bottom view of a circuit board for use in the device of  FIG. 1  accordance with an embodiment of the present invention; 
         FIG. 4  is a top view of a circuit board for use in the device of  FIG. 1  accordance with an embodiment of the present invention; 
         FIG. 5  is a representative schematic of showing the sensor positions for the biopsy device accordance with an embodiment of the present invention; 
         FIG. 6  is a perspective view of the interior mechanical mechanism of the biopsy device in accordance with an embodiment of the present invention; 
         FIG. 7  is a perspective view of the trigger and cannula of the biopsy device in accordance with an embodiment of the present invention; 
         FIG. 8  is a perspective view of the trigger and cannula of  FIG. 7  with the trough extended in accordance with an embodiment of the present invention; 
         FIG. 9  is a perspective view of the trigger and cannula of  FIGS. 7 and 8  after entrapping a sample in accordance with an embodiment of the present invention; 
         FIG. 10  is a perspective view of the trigger and cannula in a position to retrieve the specimen from the biopsy device in accordance with an embodiment of the present invention; 
         FIG. 11  is a perspective view of the biopsy syringe in accordance with an embodiment of the present invention 
         FIG. 12  is a perspective view of the syringe of  FIG. 11  mounted on the trigger in accordance with an embodiment of the present invention; 
         FIG. 13  is a cutaway top perspective view of the syringe and trigger combination of  FIG. 12  mounted on the automatic biopsy device in accordance with an embodiment of the present invention; 
         FIG. 14  is a view of the mechanism of  FIG. 6  in the “Home” position in accordance with an embodiment of the present invention; 
         FIG. 15  is a perspective view of the biopsy device illustrated in  FIG. 14  in the “Run” position with the cannula and stylet in a position to extended into the tissue in accordance with an embodiment of the present invention; 
         FIG. 16  is a perspective view of the biopsy device with the cannula being extended to cover the stylet entrapping the specimen in accordance with an embodiment of the present invention; 
         FIG. 17  is a perspective view of the biopsy device with the cannula being retracted in accordance with an embodiment of the present invention; and 
         FIG. 18  is a perspective view of the biopsy device at the point of completion of the process in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     It is advantageous to define several terms before describing the invention. It should be appreciated that the following definitions are used throughout this application. 
     For the purposes herein the term “biopsy” shall refer to the tissue sample retrieved from the body for evaluation of a possible disease tissue. 
     For the purposes herein the term “circuit boards” shall refer to any board, or other device that mechanically supports and electrically connects electronic components using any type of conductive pathway. 
     For the purposes herein the term “coagulant” shall refer to any material ha the process of which causes blood to form solid clots. 
     For the purposes herein the term “cannula” shall refer to a thin walled tube. 
     For the purposes herein the term “hemostasis” shall refer to the stopping or arresting of bleeding. 
     For the purposes herein the term “motor” shall refer to any device having the ability to convert a source of energy into a mechanical motion. 
     For the purposes herein the term “proximity sensors” shall refer to a electrical or mechanical component that detects an object within a close distance. 
     For the purposes herein the term “stylet” shall refer to a slender wire with a section removed for the purpose of collecting a specimen of tissue. 
     For the purposes herein the term “core biopsy” or needle biopsy, shall refer to any biopsy in which tissue is “obtained by insertion through the skin with a specifically designed needle that detaches tissue with an inner needle so that it can be brought to the surface in its lumen.” Dorland&#39;s Illustrated Medical Dictionary 27 th  Edison, Copyright W. B. Saunders Company, 1988. 
     The system of the present invention automatically collects and retrieves a biopsy specimen and then delivers, with or without removal of the biopsy assembly, an application material to facilitate hemostasis of the biopsy track or other puncture wound in a simple and safe manner. The device according to the invention causes the translations and movements of the parts of the disclosed biopsy device to procure a biopsy specimen and deliver the coagulant material to the biopsy track. 
     The delivered application material can also be used to provide a marker or subsequent procedures such as radiation or surgical treatments. The apparatus for collecting the biopsy specimen and delivering a coagulant materal will be described below in connection with procurement of a liver biopsy sample for the diagnosis of certain liver diseases. However, the automated biopsy device can be used for the procurement of other biopsy specimens from other vascular organs as well as facilitating hemostasis of other types of puncture wounds or tissue access tracks to prevent bleeding of these wounds. The invention can also be used for the procurement of a biopsy specimen and the delivery of a marker, therapeutic or other substance into the biopsy site. 
     The current means of obtaining a biopsy specimen from the liver is either using the aspiration technique or the cutting needle technique. The aspiration technique utilizes a common syringe and 15 to 18 gauge needle for obtaining the biopsy by the technique described by Menghini and Jamshidi. Briefly, the needle is inserted to the surface of the organ to be biopsied, penetrating slightly, suction is applied to the syringe and the needle is then advanced into the organ while maintaining suction. The needle is withdrawn from the body and the specimen flushed from the needle. In another means, a cutting needle is inserted into the organ, or tissue, and the mechanism activated causing a stylet with a specimen trough to penetrate deeper into the tissue. A cutting sheath moving outward over the stylet then cuts and entraps the tissue that had protruded into the trough. The needle is then withdrawn from the body and the specimen retrieved. 
     A complication with either technique is that after removal of the biopsy device, the tissue bleeds from the resulting biopsy tract. In the liver, the biopsy site will typically bleed up to 5 minutes however, if a major artery within the liver is hit, the bleeding can be severe requiring immediate operative intervention. The design of the disclosed automated biopsy device provides a number of advantages, including the elimination or reduction of bleeding. 
       FIG. 1  illustrates the assembled fully automated biopsy device  100  of the invention including an outer casing consisting of a left  115  and right  115 ′ half including a handle  130 , a removable top piece  120 , a removable battery pack  135  and a trigger mechanism  125  used to control the operation of the device. The exposed portion of the syringe/biopsy assembly  645  is also seen In the  FIG. 12 . As can be seen from  FIG. 1 , the biopsy device  100  is easily held and operated with one hand. 
     The assembled mechanism  200  that causes the translations and movements of the parts of the syringe/biopsy assembly  645  is illustrated in  FIG. 2  positioned within the device  100 . The components of the mechanism  200  are illustrated individually, and in more detail, in  FIGS. 6-12 . As stated heretofore, the movement of the mechanism  200  is controlled by the electronic components positioned on the circuit board  300  with surfaces bottom  305  and top  350 , the positioning of which can be seen in this Figure. The surfaces of circuit board  300  are illustrated in more detail in  FIGS. 3 and 4 . The actual physical layout of the circuit board  300  is not critical, with the exception of the sensor placement, and will be known to this skilled in the art. An example of a circuit schematic is illustrated in  FIG. 5  although alternate schematics will be evident to those skilled in the art. The sequence of steps in performing the procedure is presented in  FIGS. 11 through 18 . 
     An electrical circuit and software control the mechanism  200  along with position (proximity) sensors  355 ,  356 ,  357 ,  358 , and  359  that are located on the top surface  350  of the circuit board  300  The function of each sensor is described in more detail with respect to  FIGS. 13-18 .  FIG. 3  shows the lower surface  305  of an example circuit board on to which the electrical components required to control the motors are mounted. Situated on the lower surface  305  is an LED  307  to provide power status and motor control indication. The motor control can be automatic or the motors can be controlled individually by means of a contact switch  309  on the circuit board  300 .  FIG. 4  shows the top surface  350  of circuit board  300  and the position sensors,  355 ,  356 ,  357 ,  358 , and  359  that are photosensitive, infrared sensors or similar proximity sensors that detect the presence of the physical components of the mechanism  200 . These sensors  355 ,  356 ,  357 ,  358 , and  359  are mounted on the top surface  350  of circuit board  300  at the appropriate positions below the corresponding moving parts of the mechanism  200 . 
       FIG. 6  shows the mechanism  200  that is responsible for driving the biopsy needle/coagulant assembly  645  in the proper sequence. Motor A  215  is used to move the biopsy trigger block  240 . Motor A  215  is attached to the front plate  202  with its shaft passing through the front plate  202  and bushing  206 , to rotate gear  216  which in turn rotates the gear  217  attached to lead screw  220  and supported in plate  202  by bushing  205 . The lead screw  220  extends the length of the mechanism  200  from the front plate  202  to the back plate  250 . Rotation of the lead screw  220  through Acme nut  228  causes the biopsy trigger block  240  to translate on the guide rods  218  and  218 ′ by means of the bushings  242  and  242 ′. The biopsy trigger block  240  has a removable top plate  245  that is connected to the trigger block  240  by any means known to the art, such as hinge, slip or snap fit, etc. To insert the biopsy trigger flange  611  ( FIG. 7 ) within the slot  246  in opening  243 , the top plate  245  is removed at the time of insertion of the syringe/biopsy assembly  645  to enable the biopsy trigger flange  611  to fit within the opening  243 . Likewise top plates  227  and  210  are removed to allow placement of the plunger flange  664  and syringe flange  654  of the assembly  645  in respective slots  221  and  204  within block  205  and plate  202 , respectively. Once inserted, the respective top plates are replaced on the top of the respective blocks, thus holding the assembly  645  in place. Using a precision, Acme threaded rod (such as McMaster Carr, Part Number: 98940A1, ⅜″, right hand, 5 start) for the lead screw  220  provides sufficient translation per revolution of the biopsy trigger block  240 . 
     Motor  215 ′ moves the syringe plunger block  225  to inject the coagulant material from the syringe. The syringe plunger block  225  is a L-shaped unit with the leg of the L being created by the syringe plunger top plate  227 . Motor  215 ′ is attached to front plate  202  and, as described above with respect to motor  215 , the shaft passes through a bushing (not shown), to rotate gear  216 ′ which in turn rotates the gear  217 ′ and subsequently the lead screw  220 ′ supported in the front plate  202  by bushing  205 ′. The lead screw  220 ′ extends the length of the mechanism  200 , ending at back plate  250  after passing freely through hole  241  in block  240 . Rotation of the lead screw  220 ′ through Acme nut  228 ′ causes syringe plunger block  225  to translate on the guide rods  218  and  218 ′ by means of the bushings  207  and  207 ′. Syringe plunger block  225  has a top  227  that is removable to enable the plunger flange  664  to be placed within the slot  212  in opening  211 . Once in place, the top  227  fits on top of the block  225  and holds the plunger flange  664  in place. As with the blocks  225  and  240 , the top  210  of the front block  202  is removable. The syringe flange  654  fits within the slot  204  in opening  203 . The top  210  fits on top of the block  202  to hold the flange  654  in place. 
     For either motor, clockwise rotation of the motor causes backward movement of the respective block and vice versa. 
     The device uses a standard, commercially available, spring action, semi-automatic biopsy device  600 , well known by those in the art, and other types of biopsy devices can be substituted with slight modifications to the mechanism  200 . The examples of biopsy devices provided in Table 1, and shown in  FIGS. 7 and 8  can be used with disclosed mechanical mechanism  200  without modification. The biopsy device  600  has a trigger  610 , to which is attached a stylet  612  having a specimen trough  614  at the distal end. The stylet  612  is enclosed within a cannula  622  which is affixed to the internal slide within body  602 . A catch arm  616  extends from the trigger  610  into the body  602  of the device  600 . As the trigger  610  is pulled back, the end of the catch arm  616  engages the internal slide to which the cannula  622  is attached and allows stylet  612  to pass free through it. The enclosed internal slide is held in place, against an internal spring within body  602  by a catch mechanism. When the trigger  610  is pushed forward,  FIG. 8 , the trough  614  is exposed to the tissue which prolapses into the trough  614 . Pushed all the way in, the catch arm  616  releases the internal slide from the body  602  which, due to the stored energy of the spring, is propelled forward and the attached cannula  622  entraps a sample of tissue within the trough  614  of stylet  612  ( FIG. 9 ). Once the specimen is obtained, the biopsy device  600  is removed. The trigger  610  is pulled back to retract the cannula and then advanced without releasing the internal slide and the tissue sample  615  retrieved. 
     The disclosed invention automates this operation sequence. While designed for the semi-automatic device, other means of automating the action of the individual stylet (needle) and cannula combination or the other biopsy obtaining devices could be accomplished by those skilled in the art and incorporated in to the invention. 
     While designed for the use of a semi-automatic cutting needle biopsy device, other biopsy devices such as an aspiration needle or suction needle can be adapted for use with the automated device. 
     While designed using a mechanical mechanism for translation and movement of the biopsy device and syringe, suitable pneumatic, hydraulic and/or electromechanical mechanisms could be employed by those skilled in the art and incorporated into the invention to achieve the same effect of taking a biopsy and delivering a coagulant or other material. 
     The functional and operative position of the cutting/syringe apparatus  645  is shown in  FIGS. 11 through 18  for a biopsy with a coagulant application material. The biopsy syringe  650  is composed of a syringe barrel  652  with a flange  654 , a delivery sheath assembly  670 , having a distal section  676 , and a plunger  660  with a flange  664 , as illustrated in  FIG. 11 . As indicated in this Figure, and will be described in detail hereinafter, the delivery sheath  670  has a connector  675  for attachment to the syringe  650 , a proximal portion  672  and a transition section  674 . A user-defined volume of coagulant is drawn up into the fluid chamber of the syringe barrel  652  using customary techniques. As illustrated in  FIG. 12 , the style  614  and cannula  622  of the semi-automatic biopsy device  600  are passed through the biopsy syringe  650  and application sheath  670  according to the teachings of Krause, co-pending U.S. patent application Ser. No. 10/858,112 (“Biopsy and Delivery Device”, field Jun. 1, 2004). 
     The complete, syringe and biopsy assembly  645  of  FIG. 14 , is inserted into the mechanism at the Home position, after the top  120  of the biopsy device  100  has been opened. As illustrated in  FIG. 13 , the syringe barrel flange  654  is inserted into the slot  204 , the syringe plunger flange  664  into the slot  212  of block  225  and the biopsy trigger flange  611  into slot  243  of block  240  as described in  FIG. 6 . The tops for the respective blocks are replaced to hold the respective flanges in place. 
     The biopsy needle software is controlled using the trigger mechanism  125  that activates the power applied to the unit from the battery pack  135 . Whenever power is applied to the unit the trigger  125  is active and has two positions: Home and Run. A button  309  located on the circuit board  300 , enables the user to manually adjust the position of each block by causing each motor to move forward or backwards. Each motor is moved individually, one at a time. There is also an LED  307  for indication of status, such as: Run, Home, battery low, automatic or manual. 
     Referring to  FIG. 6 , when activated by the trigger  125  and control circuit  300 , the motor A  215  rotates the lead screw  220 , thereby moving the biopsy trigger block  240  through the rotation of the lead screw  220 . Rotating lead screw  220  through nut  228  causes block  240  to translate on the guide rods  218  and  218 ′ by means of the bushings  242  and  242 ′. Using a precision, threaded rod (such as McMaster Carr, Part Number: 98940A1, ⅜″, right hand, 5 start) for the lead screw  220  provides one inch translation for one revolution of the rod  220 . In a similar fashion Motor B  215 ′ refers to the motor controlling the large syringe plunger block  225  at the front of the unit which drives the coagulant out of the syringe barrel  652 . Other lead screws or gears can be incorporated into the device to achieve slower or faster translation of the mechanism. 
     Moving the trigger  125  to the Home position causes the software to command the unit to seek the starting position for each motor. This is done by first powering motor  215 ′ to move syringe plunger block  225  to the end of its motion at the front of the mechanism until detected by sensor  355 . The sensor  355  causes the circuit to reverse the rotation of the motor  215 ′, thus moving syringe plunger block  225  backwards seeking its home position as detected by sensor  356 . The circuit then activates motor  215  to move biopsy trigger block  240  forward from its initial position looking for the starting position as referenced by sensor  358 . If it detects that it is already at the starting position, or if it detects that it has run beyond the starting position, it then retracts biopsy trigger block  240  to the rear of the unit until detected by sensor  355  and then moves biopsy trigger block  240  forward until sensor  358  stops the forward motion at its Home position. Once the motors have stopped moving, the unit is ready for another command. The syringe and biopsy assembly  645  can be loaded in this Home position,  FIG. 13 . 
     Preferably the unit has thermally-triggered circuit breakers which prevent the system from damaging itself in the event that too much electrical current is drawn (i.e. if the blocks are forced into a collision for an extended period of time). 
     The Principle of Operation of the Mechanism 
     The operation of the invention with respect to the biopsy cutting needle is described in  FIGS. 14 through 18 , which are isolated views of the mechanism of  FIG. 6 . 
     From the Home position, as illustrated in  FIG. 14 , the trigger  125  is depressed to the Run position. The circuit activates motor A  215  driving the biopsy trigger  610  and attached catch arm  616  into device body  602  and the stylet  612  into the tissue,  FIG. 15 . The sensor  357  is positioned at the point at which the catch arm  616  releases internal slide and the cannula  622  is fired over the stylet  612  entrapping the tissue specimen,  FIG. 16 . The forward motion of the biopsy trigger block  240  is stopped after tripping sensor  357  and the motor B  215 ′ is reversed pulling the entire biopsy device  600  backwards until sensor  359  detects the biopsy trigger block  240 ,  FIG. 17 . In this position the distal end of the stylet  612  and cannula  622  have been retracted into the proximal portion  672  of stylet  670  and proximal to the transition section  674  ( FIG. 11 ) thus allowing coagulant material to flow through the distal section  676  which has an internal diameter just sufficient to allow passage of cannula  622 . Motor B  215 ′ is now activated to drive syringe plunger block  225  forward forcing the coagulant material within the syringe barrel  652  through the sheath  670 , past the retracted stylet  612  and cannula  622  and into the biopsy track. Once the sensor  355  detects the presence of syringe plunger block  225 , it stops the motor  215 ′,  FIG. 18 , completing the procedure. 
     The entire device  10  is withdrawn from the patient, the top piece  120  removed and the syringe/biopsy assembly  645  is removed from the device and the biopsy sample is then retrieved from the biopsy device  600  in the customary manner. 
     The device can also be used to deliver a beneficial agent, such as contrast agent, thrombin, radiation treatment, or the like. The applicant material can also be used to deliver therapeutic agents, such as radioactive isotopes for localized treatment of tumors, anti-cancer agents, anti-metastatic agents, and the like. Examples of anti-cancer agents include 5-fluorouracil, cisplatin, prednisone, and others described in U.S. Pat. No. 4,619,913, which is incorporated herein by reference. 
     The present invention can be employed to deliver other materials other than coagulant material into a biopsy track or used to drain and fill an abscess. 
     While the invention has been described in detail with reference to the preferred embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made and equivalents employed, without departing from the present invention. 
     ELEMENTS LIST 
     
         
         
           
               100  biopsy device 
               115 ′ Right outer casing 
               115 ″ Left outer casing 
               120  removable top piece 
               125  trigger mechanism 
               130  Handle 
               135  battery pack 
               200  assembled mechanism 
               202  Front plate 
               203  Syringe opening 
               204  Slot for syringe flange  654   
               205  Bushing for lead screw  230   
               205 ′ Bushing for lead screw  230 ′ 
               206  Bushing for motor  215  shaft 
               206 ′ Bushing for motor  215 ′ shaft 
               207  Bushing for guide rod  218   
               207 ′ Bushing for guide rod  218 ′ 
               210  Front plate top 
               211  Opening for plunger  660   
               212  Slot for plunger flange  664   
               215  Motor A 
               215 ′ Motor B 
               216  Driving gear for motor A,  215   
               216 ′ Driving gear for motor B,  215 ′ 
               217  Driven gear for lead screw  220   
               217 ′ Driven gear for lead screw  220 ′ 
               218  Guide rod  1   
               218 ′ Guide rod  2   
               220  Lead screw for biopsy pull block  240   
               220 ′ Lead screw for syringe plunger block  215   
               225  Syringe plunger block 
               227  Syringe plunger top 
               228  Lead screw nut for syringe plunger slide  225   
               240  Biopsy trigger block  241  Pass through hole for lead screw  220 ′ 
               242  Bushing for guide rod  218   
               242 ′ Bushing for guide rod  218 ′ 
               243  Opening for biopsy pull  610   
               245  Biopsy trigger block top plate 
               246  Slot for biopsy trigger flange  611   
               250  Back plate 
               300  Circuit board 
               305  Lower surface of circuit board  300   
               307  LED indicator 
               309  Mode switch 
               350  upper surface of circuit board  300   
               355  position sensor 
               356  position sensor 
               357  position sensor 
               358  position sensor 
               359  position sensor 
               600  automatic biopsy device 
               602  body 
               610  trigger 
               611  biopsy trigger flange 
               612  stylet 
               614  specimen trough 
               616  catch arm 
               622  cannula 
               624  spring 
               645  syringe/biopsy assembly 
               650  biopsy syringe 
               652  syringe barrel 
               654  flange 
               660  plunger 
               664  plunger flange 
               670  delivery sheath 
               672  proximal portion 
               674  transition section 
               675  sheath connector 
               676  distal section