in fig1 - 2 , a biopsy device 10 has a reusable hand piece 12 and a disposable probe 14 that enables economical taking of multiple percutaneous core biopsy samples by accessing a standard medical vacuum pump or wall - mounted vacuum access port ( not shown ) through an interfacing vacuum conduit 16 . in addition , the biopsy device 10 advantageously incorporates a saline flush capability received from saline supply conduit 17 . in the illustrative version , the reusable hand piece 12 is self - powered and suitable for use in conjunction with ultrasonic diagnostic imaging . the disposable probe 14 reduces the portion of biopsy device 10 that requires protective packaging to avoid contact with sharp surfaces and to keep it sterile prior to use . further economy is accomplished by reducing the portion of the biopsy device 10 that is disposed as medical waste between uses . movable components of the disposable probe 14 are advantageously locked until mounted in an access trough 18 formed in a handle housing 20 of the reusable hand piece 12 . it should be appreciated that one or more standard mechanical , pneumatic , or electrical latches ( not shown ) may be integrated into the biopsy device 10 to secure the disposable probe 14 to the reusable hand piece 12 . in fig1 - 4 , the disposable probe assembly 14 includes a substantially rectangular cover 22 sized to close the access trough recess 18 ( fig1 - 2 ). an end slot 24 formed in the cover 20 ( fig1 - 2 , 5 - 6 ) is closed by a probe union sleeve 26 attached to an inner surface 27 ( fig1 ) of the substantially rectangular cover 22 . a core biopsy needle (“ probe ”) assembly 28 passes longitudinally through the probe union sleeve 26 and is formed by a probe tube 30 that includes an underlying lateral ( vacuum ) lumen 32 that communicates with a side aperture 34 ( fig1 ) via holes 35 ( fig4 ) near a distal opening 36 of the probe tube 30 that is closed by a piercing tip 38 . a cutter tube 40 is sized to closely fit and translate within an inner diameter ( i . e ., cutter lumen ) of the probe tube 30 with a length sufficient to close the side aperture 34 with a proximal end 42 extending from the probe union sleeve 26 to attach to a cutter gear 44 , as depicted in fig1 . it should be appreciated that the probe tube defines first and second fluid passages that are separated longitudinally within the probe tube and distally communicate with each other at the side aperture 34 . in the illustrative version , the first fluid passage is defined within the cutter tube 40 and the second fluid passage is defined within the lateral lumen 32 that is “ hard walled ” apart from a cylindrical portion of the cutter lumen of the probe tube 35 . however , for a cylindrical probe tube ( not shown ), a cutter tube may be axially offset within the cutter lumen of the probe tube such that the cutter tube may separate the first and second fluid passages , especially if the cutter tube need not be retracted for retraction of samples ( e . g ., vacuum retraction , straw retraction , single sample per insertion devices ). with particular reference to fig3 , sample retrieval tube 46 is received within a proximal opening in the cutter gear 44 and in turn proximally terminates itself at a half cylinder connector 47 positioned proximate to a rear support bracket 49 attached to the generally rectangular cover 22 . as described in the cross referenced application ser . no . 11 / 198 , 558 , the half cylinder connector 47 attaches to a moving portion of a sample holding apparatus and the rear support bracket 49 attaches to a stationary portion of the sample holding apparatus ( proximal sample stacker 48 ). the relative movement increments a capture mechanism as samples are proximally stacked with vacuum being ported through the half cylinder connector 47 and sample retrieval tube 46 to extract samples from the cutter tube 40 . with continued reference to fig3 , proximal to the probe union sleeve 26 is an elongate slot 50 that is part of a vacuum assist valve assembly 52 . the cutter gear 44 includes distal and proximal annular recesses 54 , 56 flanking spur gear teeth 58 that engage the reusable hand piece 12 as described below . a more distal annular recess 60 is gripped by a first valve post 62 that is engaged to longitudinally translate in an elongate post slot 64 of a distal portion 66 of a vacuum valve actuator 68 . in fig3 , a cylindrical proximal portion 70 of the vacuum valve actuator 68 has distal and proximal o - ring grooves 72 , 73 that respectively retain distal and proximal dynamic o - ring seals 74 , 75 that move within a distally open cylindrical valve bore 76 of a vacuum valve body 78 molded onto an outer surface 79 of the substantially rectangular cover 22 . in an initial state depicted in fig5 , the vacuum valve actuator 68 is in a retracted position ( along with the cutter tube 40 ), allowing communication between a proximal vacuum port 80 and a center vacuum port 82 . in fig6 , distal translation of the vacuum valve actuator 68 enables communication between the center vacuum port 82 and a distal vacuum port 84 . the center vacuum port 82 is attached to a proximal end of a distal vacuum conduit 86 whose other distal end is connected through the rectangular cover 22 to the probe union sleeve 26 ( fig2 - 3 ). it should be appreciated that the probe union sleeve 26 includes fluidic passages that communicate between the proximal end of the vacuum lumen 32 and the distal vacuum conduit 86 as allowed by the saline flush valve assembly 87 ( fig7 ). returning to the vacuum assist valve assembly 52 of fig2 - 3 , 5 - 6 , the distal vacuum port 84 is attached to a hose nib 88 that is exposed to atmospheric pressure . hose nib 88 may include an air and / or saline filter . alternatively , hose nib 88 may be connected to a positive pressure source ( e . g ., fluid pump ) or a negative pressure source ( e . g ., vacuum pump , syringe ) to aspirate fluids . likewise , hose nib 88 may be used to lavage the tissue cavity with saline , pain medication , or bleeding control fluids . the proximal vacuum port 80 communicates through a proximal vacuum conduit 90 to the interfacing vacuum conduit 16 . in fig2 - 3 , 7 - 8 , the flush valve assembly 87 includes a proximally open saline valve bore 92 formed in a saline valve body 94 molded onto the outer surface 79 of the substantially rectangular cover 22 distal to a laterally offset longitudinal slot 96 ( fig3 ) defined in a distal portion of the substantially rectangular cover 22 . with particular reference to fig3 , a saline valve actuator 98 includes a distal cylindrical spool 100 that is sized to be slidingly received within the proximally open saline valve bore 92 . a distal o - ring groove 102 that receives a distal saline o - ring 104 and a mid - shaft o - ring groove 106 that receives a mid - shaft saline o - ring 108 are spaced on the distal cylindrical spool 100 to selectively allow communication between a proximal saline port 110 , which is attached to the distal end of the distal vacuum conduit 86 , and a center molded conduit 112 that communicates through the probe sleeve union 26 to the vacuum lumen 32 when the saline valve actuator 98 is proximally positioned , as depicted in fig7 . when the saline valve actuator 98 is distally positioned , as depicted in fig8 , the center molded conduit 112 communicates with a distal saline port 114 that is attached to a proximal end of the saline supply conduit 17 . a proximal end of the saline valve actuator 98 is attached to a saline slot link 116 that longitudinally slides within the laterally offset longitudinal slot 96 extending a proximal carriage engagement member 118 out of the inner surface 27 of the substantially rectangular cover 22 . with reference to fig1 - 2 , 9 - 11 , the reusable hand piece 12 , as described in previously cross referenced u . s . patent application ser . no . 11 / 198 , 558 includes four user controls aligned on a top surface 160 of the housing 20 , specifically from most distal to most proximal : a forward motor rotation key 162 , a reverse motor rotation key 164 , a saline flush key 166 and a slide button 168 for selecting insertion mode or sample taking mode . the keys 162 - 166 control a control circuit 170 , which may include integral power storage ( e . g ., batteries , fuel cell , etc .) for untethered use . with particular reference to fig1 , the forward motor rotation key 162 causes a dc motor 172 to rotate its motor output shaft 174 in a forward rotation . a slide spur gear 176 includes an internal keyed engagement with a longitudinal key groove 178 on the motor output shaft 174 that allows longitudinal positioning by the slide button 168 . in particular , fore and aft brackets 180 , 182 of the slide button 168 engage distal and aft annular grooves 184 , 186 that flank spur gear teeth 188 of the slide spur gear 176 . when the slide button 168 is moved distally , the slide spur gear 176 engages a tissue penetration gear 190 that spins on a common shaft centerline 192 forward of a gearbox input gear 196 . gearbox input gear 196 consists of a distal small gear 198 and a proximal large gear 200 . the tissue penetration gear 190 has spur gear teeth 206 that engage the slide spur gear 176 . a frame post 212 projects proximally from an aft wall 234 of a frame 204 with a strike pin 214 projecting upwardly from the frame post 212 . in fig1 - 12 , a circular cam wheel 216 is attached to a distal side of the tissue penetration gear 190 . rotating the tissue penetration gear 190 urges the strike pin 214 , and thus the frame 204 , proximally . in fig1 , 13 , left and right spring cavities 218 , 220 ( when viewed from above ), formed longitudinally in distal corners of the frame 204 , respectively receive inwardly projecting left and right tabs 222 , 224 ( fig1 ) from the cover 20 and receive left and right compression springs 226 , 228 . in particular , a distal end of each compression spring 226 , 228 presses against a distal inner surface of the respective spring cavity 218 , 220 . a proximal end of each compression spring 226 , 288 is grounded against a respective tab 222 , 224 of the cover 20 . thus , the frame 204 is biased distally within the cover 20 . movement of the frame 204 proximally compresses these compression springs 226 , 228 that thereafter assert a restoring force . when the slide button 168 is moved proximally , the slide spear gear 176 is moved into engagement with the gearbox input gear 196 , specifically the distal small gear 198 , which engages and turns a translation large input gear 230 whose shaft 232 passes through the aft wall 234 of the frame 204 . the proximal large gear 200 of the gearbox input gear 196 engages and turns a rotation small input gear 236 whose shaft 238 passes through the aft wall 234 . the frame 204 includes a carriage recess 240 , defined between a partition 242 and the aft wall 234 . the carriage recess 240 contains longitudinally aligned left side lead ( translation ) screw 244 and right - side rotation spur gear 246 that are attached for rotation respectively with the shafts 232 , 238 . the partition 242 is positioned aft of the left and right tabs 222 , 224 of the cover 20 and also defines in part the left and right spring cavities 218 , 220 . the rotation spur gear 246 engages the cutter gear 44 when the disposable probe 14 is inserted , imparting a rotation as the cutter tube 40 and cutter gear 44 translate longitudinally in response to the rotation of the lead ( translation ) screw 244 . this translation is caused by lead screw threads 248 . in particular , a distal carriage ( cutter carriage ) 250 is longitudinally moved on the lead screw threads 248 . distal and proximal j - hook extensions 252 , 254 project downwardly from the distal carriage 250 to engage the distal and proximal annular recesses 54 , 56 of the cutter gear 44 ( fig3 ). distal of the distal carriage 250 , a biasing spring 256 urges against the distal carriage 250 , which assists in engagement of the lead screw threads 248 with the distal carriage 250 . in fig1 , 14 - 15 , a sliding pin 260 has a proximal carriage sliding pin retainer 266 attached to a proximal carriage 258 . a shaft 264 of the sliding pin 260 also passes through a distal carriage sliding pin retainer 270 attached to the distal carriage 250 . sliding pin 260 has a proximal end 262 and a distal end 268 to prevent the sliding pin 260 from disengaging from the carriage sliding pin retainers 266 , 270 . a sliding pin spring 272 resides on the sliding pin 260 and is constrained at each end by carriage sliding pin retainers 266 , 270 . with the components of the reusable handpiece 12 now introduced , a sequence of use of the biopsy device 10 will be described . the disposable probe assembly 14 is installed into the reusable hand piece 12 . in so doing , the distal carriage 250 engages the cutter gear 44 to position ( translate ) the cutter tube 40 , initially in a distal position as depicted in fig1 . during installation , the proximal carriage 258 engages the proximal carriage engagement member 118 feature located on saline slot link 116 that engages the proximal portion of the saline valve actuator 98 . a proximally stacking sample retrieving device 48 is attached to the disposable probe assembly 14 to provide a pneumatic vacuum bias to the cutter tube 40 and to hold retracted tissue samples . with the biopsy device 10 assembled , the reusable handpiece 12 is manipulated to insert the piercing tip 38 of the core biopsy needle ( probe ) assembly 28 into tissue . penetration of dense tissue is assisted by moving the slide button 168 distally to a “ tissue insertion mode ” wherein the slide spur gear 176 engages the tissue penetration gear 190 . depression of the forward motor rotation key 162 turns these gears 176 , 190 causing the circular cam wheel 216 to turn against strike pin 214 that creates proximal longitudinal motion of frame 204 and the attached core biopsy needle ( probe ) assembly 28 of approximately 0 . 1 inch at a rotation rate of 7 cycles per second ( fig1 ). left and right compression springs 226 , 228 provide the restoring distal longitudinal motion to frame 204 and probe assembly 28 as left and right compression springs 226 , 228 are repeatedly compressed between the distal surface of the left and right spring cavities 218 , 220 of the frame 204 and the left and right tabs 222 , 224 of the housing 20 . the restoring distal longitudinal motion to frame 204 and core biopsy needle ( probe ) assembly 28 result in a corresponding distal motion of piecing tip 38 that assists in penetrating tissue . with the probe assembly 28 positioned , the slide button 168 is moved proximally to move slide spur gear 176 into engagement with the gearbox input gear 196 . depression of the reverse motor rotation key 164 causes the distal carriage 250 to retract ( fig1 ). thereby , the vacuum assist valve assembly 52 ( fig5 ) communicates vacuum through saline flush valve assembly 87 ( fig7 ) of the disposable probe assembly 14 ( fig1 ) through the vacuum lumen 32 to a now open side aperture 34 in the probe tube 30 ( fig4 ) to prolapse tissue . vacuum is maintained by a lower pressure also communicating through the cutter tube 40 through the proximal sample stacker 48 . depression of the forward motor rotation key 162 ( fig1 ) distally translates the distal carriage 250 and thus the cutter tube 40 to sever a tissue sample ( fig2 ) as well as shifting the vacuum assist valve assembly 52 to a distal position ( fig6 ) that communicates an increased pressure ( e . g ., atmosphere ) through the saline flush valve assembly 87 ( fig7 ) through the vacuum lumen 32 to the side aperture 34 , allowing the vacuum through the cutter tube 40 to retract the tissue sample ( fig2 ). at this point or after subsequent sample taking cycles , the surgeon my elect to flush tissue debris or coagulated blood from the vacuum lumen 32 , side aperture 34 and cutter tube 40 of the probe assembly 28 . by further depression of the forward motor rotation key 162 , the distal carriage 250 advances slightly forward , drawing the proximal carriage 258 onto the lead screw threads 248 , and thereafter the distal carriage 250 free wheels . thereby , the flush valve assembly 87 switches from pneumatically coupling the lateral lumen 32 to the vacuum assist valve assembly 52 to coupling the saline supply ( not shown ) to the vacuum lumen 32 . thereby , the vacuum drawn through the cutter tube 40 causes saline ( or other liquid provided ) to be drawn through the vacuum lumen 32 and into a distal end of the cutter tube 40 and out of the disposable probe assembly 14 , through proximal sample stacker 48 and then into the fluid collection canister ( not shown ) located near the vacuum pump . when the proximal carriage 250 is not fully distal , the flush valve 87 is positioned proximal of its fully distal position and prevents saline from communicating with the lateral lumen 32 of the probe assembly 28 . control implementation may include sensing of the position of the distal carriage 250 such that motor operation stops distal travel of the distal carriage 250 prior to distal translation of the proximal carriage 258 , requiring release of the forward motor rotation key 162 prior to actuating again to indicate a desire for saline flush . alternatively , a separate override button ( not shown ) may be used that continues forward rotation of the lead screw 244 to effect the saline flush feature . it should be appreciated that in the illustrative version , the distal carriage 250 does not freewheel in its proximal - most position . instead , rotation of the motor is stopped as the distal carriage 250 is about to contact the proximal carriage 258 with closed - loop control based on an encoder ( not shown ) coupled to the dc motor 172 enabling accurate positioning of the motor output shaft 174 . alternatively , freewheeling may be incorporated at the proximal - most position of the distal carriage 250 by adding a section of no helical threads to the proximal end of the lead ( translation ) screw 244 equal to the longitudinal thickness of the distal carriage 250 . by virtue of the foregoing , with one - handed operation , a clinician is able to select between a plurality of ports ( e . g ., vacuum pressure , atmospheric pressure , saline supply ) that can communicate with a side aperture 34 of a needle assembly 28 of core biopsy device 10 . in particular , valve mechanisms are contained on the hand piece that need only selectively port a constant vacuum source without the necessity for a separate , expensive programmed control module . one advantage of such an economical capability is providing “ on - demand ” saline flush to the side aperture 34 ( or distal opening ) of the needle assembly 28 . during normal tissue sampling , the side aperture 34 pressure levels transitions from vacuum during cutting to atmospheric pressure while the tissue sample is being transported proximally out of the reusable handpiece 12 . clearing tissue debris from the needle assembly 28 at the press of a saline push key 166 during the sample ensures proper operation so that the desired number of samples may be taken . it should be appreciated that any patent , publication , or other disclosure material , in whole or in part , that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions , statements , or other disclosure material set forth in this disclosure . as such , and to the extent necessary , the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference . any material , or portion thereof , that is said to be incorporated by reference herein , but which conflicts with existing definitions , statements , or other disclosure material set forth herein , will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material . 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 spirit and scope of the appended claims . additionally , each element described in relation to the invention may be alternatively described as a means for performing that element &# 39 ; s function . for example , one or more sensors may be incorporated into the hand piece 12 to sense the actual position of each carriage or to sense the particular disposable probe assembly assembled into the hand piece 12 . as another example , use of a proximal carriage for saline flush takes advantage of this additional motive device that is dedicated for sample retrieval in other versions of the disposable probe assembly ( i . e ., straw ). in some applications consistent with the present invention where two carriages are not required or desired , an alternative saline valve selection may be incorporated where a separate electromechanical valve actuator may be incorporated that is not driven by the lead screw . as an additional example , biasing the cutter tube 40 with a vacuum source advantageously assists in both prolapsing tissue as well as retracting tissue samples from the probe assembly 28 . however , applications consistent with the present invention may include reversing the direction of fluid flow through the cutter tube and out of the lateral lumen 32 . in addition , prolapsing of tissue may be alternatively achieved by closing the lateral lumen and allowing the vacuum bias through the cutter tube 40 to effect tissue prolapse . in addition , a pressurized liquid source may be directed by the flush valve assembly to forcibly push out a tissue sample or debris without the assistance of a vacuum bias on the cutter tube . as yet a further example , while the illustrative versions advantageously utilize a single motor and a single lead screw to translate two carriages , applications consistent with aspects of the present invention may use two motors and two lead screws or one motor selectively coupled to one of two lead screws , each having a carriage . as yet an additional example , while selective depression of the saline push key 166 provides clinical flexibility , it should be appreciated that the dual carriage lends itself to alternatively mechanizing automatic saline flush after each cutting cycle .
a biopsy device and method are provided for obtaining a tissue sample , such as a breast tissue biopsy sample . the biopsy device includes a disposable probe assembly with an outer cannula having a distal piercing tip , a cutter lumen , and a cutter tube that rotates and translates past a side aperture in the outer cannula to sever a tissue sample . the biopsy device also includes a reusable hand piece with an integral motor and power source to make a convenient , untethered control for use with ultrasonic imaging . the reusable hand piece incorporates a probe oscillation mode to assist when inserting the distal piercing tip into tissue . a saline valve positioned by the reusable hand piece communicates a saline supply through the probe assembly to perform saline flush of the cutter tube and outer cannula .