# Patent

## Title
Forward-fired automatic tissue sampling apparatus with safety lock

## Abstract

An apparatus for the automated and facilitated handling and operation of a biopsy needle system, having a first needle component and a second needle component. The first and second needles are provided with first and second handles, respectively, which are fitted into first and second yokes of the apparatus. The apparatus is configured to maintain the first and second needles in a first position, during insertion of the biopsy needle point into the tissue being sampled. The apparatus is further configured to forwardly move the first and second needles into subsequent positions, respectively, in rapid, automated succession so as to segment and enclose a tissue sample, which may be tested after removal of the biopsy needle system from the tissue. A tissue sample inspection feature permits facilitated repositioning and maintenance of the first needle relative to the second needle after retrieval of the tissue sample to, in turn, enable inspection of the retrieved tissue sample without removal of either needle from the apparatus. The apparatus is further configured so as to be actuatable from positions adjacent the front or the rear of the apparatus housing. A safety lock feature is provided, which prevents inadvertent cocking motions, when the apparatus is actuated by either its rear or forward firing buttons.

## Background
BACKGROUND OF THE INVENTION
1. The Technical Field
The present invention relates to tissue sampling devices associated with biopsy needles, and in particular, to an automatic tissue sampling apparatus for utilizing two-piece biopsy needle systems for facilitating the retrieval of a tissue sample for testing.
2. The Prior Art
A typical biopsy needle system utilized in obtaining tissue samples is composed of two parts, a first needle and a second needle. The first needle consists of a substantially solid shaft, having a first handle disposed at one end. A cutting point, to facilitate insertion of the needle into the tissue to be sampled, is located at the other end of the shaft, opposite to the position of the handle. Positioned proximate to the cutting point is a tissue holding region, which is in the form of a cut-out region or flat in the otherwise substantially cylindrical shaft.
The second needle is typically hollow, and has a cutting point disposed at one end. At the other end, a second handle is disposed. The hollow passageway extends through the second handle, to enable the solid shaft of the first needle to be inserted into the passageway and into and through the entire hollow shaft of the second needle.
The shaft of the first, inner, solid needle is typically greater in length than the entire second, outer, hollow needle structure. When the first and second handles are placed in a particularly spaced co-axial configuration, the hollow shaft of the second needle covers the tissue holding region of the first needle. The tissue holding region may be exposed by projecting the first needle further into the second needle, bringing the first and second handles closer together.
To obtain a tissue sample, the biopsy needle system is typically inserted into a patient, into the specific tissue to be sampled, at the desired cell mass to be investigated, with the first and second needles relatively positioned in the first described configuration, so that the tissue holding region is covered. The tissue holding region is then exposed, by the operator holding the second handle of the second needle stable while projecting the first needle forward a short distance along its sharp pointed region-until a portion of the tissue being tested surrounds the flat cut-out of the tissue holding region.
The second needle, which also has a sharp, though hollow, point disposed at the end of the hollow shaft opposite the second handle, is then moved forward, relative to the now-stabilized first needle—to cut off the tissue sample from the rest of the tissue, and cover the tissue sample about the flat cut-out of the tissue holding region. The angled cutting point of the second needle serves to sever the tissue sample. The first and second needles are typically maintained in a particular angular concentric orientation with respect to one another, prior to insertion, so as to maintain the forwardmost portion of the second needle point centered when positioned over the flat, cut-out region of the first needle.
After the tissue is severed and confined between the first and second needles, the first and second needles will be brought back to the same relative positions they occupied immediately prior to initial insertion of the biopsy needle system into the patient. To prevent loss or contamination of the tissue sample, the first and second needles are typically removed from the patient in this tissue-isolating configuration.
As the configuration of the first and second needles, utilized for initial insertion, and final removal from the patient, requires that the first and second handles be spaced apart in a particular configuration, the manual manipulation of such a biopsy needle system requires considerable dexterity, concentration and skill on the part of the operator. The concentration necessary to maintain the proper spacing may detract from the concentration necessary to make insertion and removal of the biopsy needle as painless as possible for the patient. Accordingly, it is desirable to provide a form of automatic tissue sampling apparatus, which accomplishes some, if not all of the handling steps just described—so that the operator may be concerned with the crucial initial step of insertion and final step of removal, of the biopsy needle system; to reduce the amount of discomfort to the patient, to improve the quality of the results of the tissue sampling procedure, and to enhance the successful repeatability of the procedure, from one patient to the next.
Examples of prior art automatic tissue sampling apparatus include those disclosed in PCT application No. PCT/SE83/00112, Swedish Patent No. 8600755, U.S. Pat. No. 4,699,154, issued to Lindgren, U.S. Pat. Nos. 4,944,308, and 4,953,558, issued to Akerfeldt, EPO Application No. 0 318 447 and Swiss Patent No. 483 829.
In the PCT '00112 application, an automatic tissue sampling apparatus is disclosed, in which the first needle of the biopsy needle system is propelled forward by a pressure plate which is driven by a compressed spring, and the second needle is propelled by a movable slide which receives the second handle of the second needle. The movable slide for holding the second needle is also propelled by a compressed spring. In order to prepare the apparatus for use, each of the springs and respective slides must be cocked separately, either manually or through the use of a specially shaped tool. The slide for the second handle is held in place by a catch which is configured to be released upon contact with a projection arranged upon the slide for the first handle of the first needle. The pressure plate for the first handle of the first needle is, in turn, retained in its cocked position by a trigger which is actuatable by the operator. While it is possible to cock each of the spring with the biopsy needle already in place, it is contemplated that such cocking could take place well prior to loading of the needle.
In the operation of the PCT '00112 device, once the springs have been cocked and the biopsy needle system has been loaded (either before or after cocking), the operator inserts the biopsy needle system into the tissue to be sampled, as previously described. He or she may then depress the trigger which releases the spring for propelling the first needle. As the first needle is moved forward, the pressure plate releases the retaining mechanism which has been previously holding the movable slide for the second handle of the second needle. The second needle is thus moved forward shortly after the first needle, completing the sampling movement. The trigger in the apparatus is biased by a spring into position to retain the compressed spring for the first needle slide, and is configured to provide increasing resistance to depression, up until a predetermined position, at which point, the resistance is sharply increased and further depression results in the immediate release of the compressed spring. No means are provided for preventing inadvertent actuation of the automatic tissue sampling apparatus.
Due to the inherently hazardous nature of the extremely sharp points of the biopsy needle and the power of the spring-loaded mechanism, it is desirable, therefore, to provide a tissue sampling apparatus which has an automatically engaging safety mechanism, which must be consciously overcome before the tissue sampling apparatus may be actuated. In addition, it may be often awkward and/or difficult to manually overcome the force of the uncompressed springs which drive the movable slides. Accordingly, it would be desirable to provide an automatic tissue sampling apparatus which may be readily prepared for use, immediately before insertion, without the need for extreme physical exertion or the use of awkward and/or specially configured tools.
The tissue sampling device embodied in U.S. Pat. No. 4,699,154 to Lindgren discloses a housing in which two slides are mounted for longitudinal movement, the slides being configured to receive the first and second handles of the first and second needles, respectively. Each of the slides is propelled by a pair of compressed springs. The rearward slide, for propelling the handle of the first needle, is propelled by springs which bear against a rear wall of the housing. The slide for the handle of the second needle is propelled by compressed springs which bear against a fixed, transversely-extending wall arranged in the housing between the forward and rear slides. Both of the slides are arranged to have a guide member extending through them. A drawbolt is operably associated with each of the slides for limited axial movement relative thereto such that when the drawbolt is pulled backward, both of the slides are simultaneously drawn against the bias of the respective springs, to a cocking position. When the cocking position is reached, retaining members associated with each of the slides engage the respective slides to retain them in their cocked positions.
In a manner similar to that discussed with regard to the PCT '00112 application, an external triggering mechanism is provided, which is actuatable by the operator to release the retaining mechanism for the slide for the first needle. Once the slide for the first needle has been propelled forward a predetermined distance, a projection on the first slide releases the retaining mechanism for the slide for the handle of the second needle, enabling it to be propelled forward by its respective springs.
One possible drawback to the tissue sampling apparatus of the Lindgren '154 patent is that it is configured so that both sets of springs are compressed, and the slides brought into their retained positions by a single pulling motion upon the drawbolt. Accordingly, the combined strengths of all of the springs must be overcome in order to cock the mechanism. Due to the substantial power stored in the springs which is necessary for the rapid operation of the tissue sampling apparatus, it may be difficult for certain operators to rapidly and easily operate the cocking mechanism. Accordingly, the prior art addressed an automatic tissue sampling apparatus with a built-in cocking mechanism which is readily and easily operated, and which does not require substantial strength or effort in order to arm the apparatus. See, e.g., Schramm, U.S. Pat. No. 5,507,298.
The tissue sampling device of the Lindgren '154 patent is also provided with a safety mechanism, for precluding inadvertent actuation. However, the safety mechanism is configured such that it must be positively engaged by the operator, in order to place the tissue sampling apparatus into condition that it cannot be accidentally fired. Accordingly, the effectiveness of the safety device is dependent upon the operator remembering to set the safety. It would be more desirable to provide an automatic tissue sampling apparatus which is configured with a safety device which engages automatically upon the cocking of the apparatus, and is thereby not dependent upon the operator's remembering to engage the safety. Rather, it would be desirable to configure the safety device so the operator must affirmatively disengage the safety before the tissue sampling apparatus can be actuated to fire it.
Swiss Patent No. 483 829 discloses a “gun”-shaped automatic tissue sampling apparatus, in which the springs are cocked by direct pulling force, and so suffers from the same potential drawback of requiring substantial difficulty and effort to arm the device.
U.S. Pat. Nos. 4,944,308 and 4,953,558, issued to Akerfeldt, and EPO Application No. 0 318 447 disclose an automatic tissue sampling apparatus, in which the springs for the slides for the first and second needles are cocked by rotating in a sequential manner. Tabs on the slides ride on cam surfaces to force the slides backward against the springs requiring substantial effort to operate.
In addition to the foregoing, it is well known that often during tissue sampling procedures, the quality and/or quantity of the tissue being sampled may vary from procedure to procedure.
Accordingly, it has been desirable to provide a means for permitting inspection of the tissue sample, without removing the biopsy needle components from the tissue sampling apparatus. In that way, should the size or quality of the sample be inadequate, the biopsy needle may be reinserted into the very same patient for another attempt at obtaining a suitable sample. Such a sample inspection procedure has also permitted access to the sample for subsequent deposit of same onto a microscope slide or other sample holding apparatus for further processing of the tissue sample.
Such prior art tissue sampling apparatus such as those disclosed in the PCT '00112 application and in the Lindgren '154 patent are known to be large, relatively heavy and complicated devices, which are also relatively costly.
The prior art endeavored to provide an improved automatic tissue sampling apparatus which is easy to load and bring into readiness for use, without undue exertion and/or complicated manipulation of its components; while providing a facilitated, positive locking, tissue sample inspection capability.
Thus, the prior art has provided an automatic tissue sampling apparatus which is provided with an automatically engaging safety device, which does not rely upon the operator for its effectiveness and which must be affirmatively disengaged before the tissue sampling apparatus may be actuated.
The prior art also sought, as another goal, the provision of an automatic tissue sampling apparatus which is less complicated and therefore easier and less expensive to construct, and which has a lighter construction for greater ease of operation and manipulation.
Yet another goal of the prior art was to provide an automatic tissue sampling apparatus which is provided with various internal shock and sound absorbing means so as to render the apparatus quieter and less jarring in operation, so as to decrease the actual and/or perceived discomfort of the patient during the tissue sampling procedure, while ensuring better practitioner accuracy during the procedure.
In the prior art apparatus of U.S. patent application Ser. No. 07/753,602, now U.S. Pat. No. 5,284,156, the handles of the first and second needles were borne upon separate yokes which were each configured for longitudinal reciprocating movement within a housing. Both yokes were biased toward the front of the housing and, when the device is cocked, were held in retracted positions by separate retaining mechanism. When the apparatus was “fired”, the yoke bearing the handle of the first needle moved rapidly forward, and as it approached its forwardmost position, it approached a central support. Resilient members on the yoke and on the central support member caused the yoke to decelerate prior to its contact with the central support. Before the resilient members could cause the yoke to “rebound” from the central support, a second “firing” button on the yoke released the retaining mechanism holding the yoke for the second needle. The resilient members by then exerted sufficient force to slightly force the first yoke backward a short distance from the central support. This rebound was necessary to permit the retaining mechanism for the second yoke to engage during subsequent cocking of the apparatus.
While the structure and mode of operation of the prior art automatic tissue sampling apparatus of application Ser. No. 07/753,602, U.S. Pat. No. 5,284,156, represented a substantial improvement over the prior art in terms of shock and noise reduction, as well as with respect to ease and safety of operation, some jarring could still exist during operation and, as a general matter, it is always desirable to seek to improve on the performance of such a device, to reduce such jarring to both improve a patient's physical and psychological well-being, and as well to further improve upon the effectiveness of the device in retrieving tissue samples.
Tissue sampling apparatus which have rearwardly positioned actuation buttons may require that the operator reposition his/her grip, since it is often the situation that the apparatus is grasped at a forward end during placement of the needle in the patient. To address this, the prior art sought to provide an automatic tissue sampling apparatus which has a firing member which is accessible without requiring repositioning of the operator's grip prior to actuation of the apparatus.
An automatic tissue sampling apparatus having a forward located actuating button is disclosed in prior art reference Schramm et al., U.S. Pat. No. 5,507,298. While the apparatus disclosed in that reference likewise represented a significant advance in the art of automatic tissue sampling apparatuses, that device is not without certain functional features which may be of concern. Specifically, the safety mechanism provided in that apparatus, for preventing undesired actuation of the apparatus, comprises, in part, a laterally slidable (depending upon the “cocked” status of the device) shaft. As the device is cocked, the shaft is moved laterally, by following a cam surface on the cocking shaft, to a position which prevents the front and rear firing buttons (which are mechanically interlocked) from being actuated, until such time as the shaft is moved back to its original position. However, it has been found that in the process of exerting pressure on the rear firing button to actuate the automatic tissue sampling apparatus, in this type of device, a user can sometimes inadvertently exert upward force on the cocking lever, causing it to be moved away from its “at rest” position, while the firing action is taking place. When the cocking shaft is away from its “at rest” positions, during the firing action, it is possible for some of the internal components to clash, resulting in component stresses, including possible damage to the structure.
Therefore, it is an additional object of the invention to provide an improved automatic tissue sampling apparatus which is provided with an improved safety lock structure, which is configured to prevent inadvertent cocking movements of the cocking mechanism, so as to preclude disruption of the firing action as well as to reduce the undesired stresses and interferences amongst the structural components, toward improved apparatus operation, including sampling reliability and reduced potential for internal damage to the apparatus, during firing.
These and other objects and goals of the invention will become apparent in light of the present Specification, Drawings and Claims.
SUMMARY OF THE INVENTION
The present invention comprises an automatic tissue sampling apparatus, for use with a biopsy needle system of the kind including a first needle having a shaft member and two ends, a first handle disposed at one end of the shaft member, a cutting point disposed at the other end of the shaft member, and a tissue holding region positioned between the cutting point and the first handle, and a second needle having a hollow shaft, a cutting point disposed at one end of the hollow shaft, and a second handle with a passageway arranged therethrough for reciprocation of the first needle.
The automatic tissue sampling apparatus comprises a housing. Handle holders are operably disposed in the housing, for receiving and holding the first and second handles of the first and second needles, toward moving same. A propulsion mechanism is operably disposed in the housing, for moving the handle holders within the housing, so as to move the needle handles to expose and subsequently cover, the tissue holding region, when the biopsy needle system has been positioned at a desired location within a tissue to be sampled, the propulsion mechanism being operably biased so as to tend to move the handle holders so as to expose and subsequently cover the tissue holding region, unless the handle holders are restrained. A cocking mechanism is provided, for placing the handle holders, and, in turn, the first and second needles of the biopsy needle system into suitable respective positions within the housing for subsequent movement by the propulsion mechanism. A retaining mechanism is provided for holding the handle holders, and, in turn, the first and second needles of the biopsy needle system in the suitable respective positions within the housing, prior to actuation of the apparatus. A release mechanism is provided for actuating the retaining mechanism, so as to release the handle holders and enable the propulsion mechanism to move the first and second needles, so as to expose, and subsequently cover the tissue holding region. A firing mechanism is provided which is operably connected to the release mechanism, for causing the actuation of the propulsion mechanism. A safety lock mechanism is operably interconnected between the firing mechanism and the cocking mechanism, for precluding undesired actuation of the firing mechanism until both handle holders are fully cocked, and for precluding undesired actuation of the cocking mechanism, during actuation of the firing mechanism.
The cocking mechanism preferably comprises a cocking shaft, mounted in the housing for longitudinal reciprocating movement therein, and operably interconnected with the handle holders; and a cocking lever pivotably mounted on a rear wall portion of the housing, proximate the rear firing member, and connected to the cocking shaft so that upon upward pivoting of the cocking lever, the cocking shaft is drawn rearwardly relative to the housing.
Preferably, the safety lock mechanism comprises a safety button, mounted in the rear portion of the housing, for reciprocating movement in a direction transverse to the cocking shaft between first and second positions. The safety button has engagement structures disposed thereon, configured for selective engagement with the cocking shaft, when the safety button is in its first position, and with the rear firing member, when the safety button is in its second position, so that when the safety button is in its first position, the cocking shaft and, in turn, the cocking lever, are precluded from movement, and when the safety button is in its second position, the firing button is precluded from movement. Simply put, when the safety button is in its first position, one can operate the rear firing member but cannot operate the cocking lever. Alternatively, when the safety button is in its second position, one can operate the cocking lever, but cannot depress the rear firing member.
In this embodiment, the safety button has a first notch, with an engagement shoulder therein, operably configured to enable the cocking shaft to move relative to the safety button when the safety button is in its second position, and to engage with a shoulder disposed on the cocking shaft to prevent movement of the cocking shaft relative to the safety button, when the safety button is in its first position. The safety button preferably has a second notch, operably configured to enable the rear firing button to move, when the safety button is in its first position, and to engage with a shoulder disposed on the rear firing button, to preclude movement thereof, when the safety button is in its second position.
In a preferred embodiment, the firing mechanism comprises a rear firing member operably positioned on a rearward portion of the housing. The automatic tissue sampling apparatus preferably further comprises a front firing member operably positioned on a forward portion of the housing, the front firing member being operably interconnected with the rear firing member.



BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a prior art automatic tissue sampling apparatus, having a double-needle biopsy needle system loaded therein.
FIG. 2 is a perspective view of the apparatus according to FIG. 1, with the cover opened to show how the biopsy needle system is loaded into the apparatus.
FIG. 3 is a perspective view of the apparatus, according to FIG. 2, showing, in partial cutaway, further details of the construction of the apparatus.
FIG. 4 is a top plan view of the apparatus, according to FIG. 2.
FIG. 5 is a side elevation, in section, of the prior art apparatus, with a biopsy needle system loaded therein, in its initial configuration prior to cocking, further showing, in enlargement, the relative positions of the needles.
FIG. 6 is a side elevation, in section, showing the apparatus according to FIG. 5 during the first cocking stroke, further showing, in enlargement, the relative positions of the handles.
FIG. 7 is a side elevation, in section, of the apparatus according to FIG. 5, showing the apparatus upon completion of the first cocking stroke and release of the cocking elements immediately thereafter, further showing, in enlargement, the relative positions of the needles.
FIG. 8 is a side elevation, in section, of the apparatus according to FIG. 5, shown during the second cocking stroke further showing, in enlargement, the relative positions of the needles.
FIG. 9 is a side elevation, in section, of the apparatus according to FIG. 5, shown fully cocked, after release of the cocking elements, and ready for insertion of the biopsy needle system into the tissue to be sampled, further showing, in enlargement, the relative positions of the needles.
FIG. 10 is a side elevation, in section, of the apparatus according to FIG. 5, shown immediately after the button has been depressed, further showing, in enlargement, the relative positions of the needles.
FIG. 11 is a side elevation of the apparatus, in section, according to FIG. 5, showing the apparatus after firing but before the yokes have returned to their initial positions, equivalent to the positions prior to cocking, further showing, in enlargement, the relative positions of the needles.
FIG. 12 is a schematic perspective view, illustrating the operation of the automatically deployed safety mechanism.
FIG. 13 is a top perspective view, in partial section, of another prior art automatic tissue sampling apparatus, in which at least a front firing member is positioned for actuation of the apparatus.
FIG. 14 is a side elevation, in partial section, of an alternative preferred embodiment of the device of FIG. 13.
FIG. 15 is a front elevation of the apparatus shown in FIG. 13.
FIG. 16 is a side elevation of an automatic tissue sampling apparatus, according to a preferred embodiment of the present invention.
FIG. 17 is a top plan view of the automatic tissue sampling apparatus of FIG. 16, with the cover opened to illustrate the interior mechanism of the automatic tissue sampling apparatus, in the uncocked/fired configuration.
FIG. 18 is a side elevation, in section, of the automatic tissue sampling apparatus, according to the embodiment of FIGS. 16-17, taken along line A-A of FIG. 23, showing the interior mechanism in the uncocked/fired configuration.
FIG. 19. is a side elevation, in section, of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-18, taken along line A-A of FIG. 23, showing the interior mechanism in the half-cocked/sample notch exposed position.
FIG. 20 is an end elevation, in section, of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-19, taken along line B-B of FIG. 18.
FIG. 21 is an end elevation, in section, of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-20, taken along line C-C of FIG. 18.
FIG. 22 is a front end elevation of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-21.
FIG. 23 is a rear end elevation of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-22.
FIG. 24 is a fragmentary side section of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-23, taken along line H-H of FIG. 17.
FIG. 25 is a fragmentary side section of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-24, taken along line E-E of FIG. 17.
FIG. 26 is a fragmentary top section of the safety lock portion of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-25, taken along line D-D of FIG. 16.
FIG. 27 is a fragmentary side section of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-26, taken along line F-F of FIG. 17.
FIG. 28 is an end elevation in section of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-27, taken along line G-G of FIG. 18.
FIG. 29 is an end elevation in section of the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-28, taken along line I-I of FIG. 18.
FIG. 30 is a top plan view of the cocking shaft for the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-29.
FIG. 31 is a side elevation of the cocking shaft for the automatic tissue sampling apparatus according to the embodiment of FIGS. 16-30.
FIG. 32 is an end elevation, in section, taken along line D-D of FIG. 30.
FIG. 33 is an end elevation, in section, taken along line C-C of FIG. 32.
FIG. 34 is a perspective view of portions of the safety lock mechanism of the embodiment of FIGS. 16-34.
FIG. 35 is a perspective view of a needle system for use with the automatic tissue sampling apparatus of FIGS. 16-34.



DETAILED DESCRIPTION OF THE DRAWINGS
While the present invention is susceptible of embodiment in many different forms, there is shown in the drawings and will be described herein in detail, several specific embodiments, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention, and is not intended to limit the invention to the embodiments illustrated.
A prior art automatic tissue sampling apparatus 20 is illustrated in FIGS. 1-12, having biopsy needle system 22 already loaded therein. Automatic tissue sampling apparatus 20 includes housing 24 with cover 25. Automatic tissue sampling apparatus 20 is cocked using lever 28, which is provided with finger gripping portion 29 and thumb rest portion 30. Lever 28 is mounted for facilitated pivotal movement around pin 32, which is mounted in projection 33 of housing 24. Upon cocking, safety button 35 automatically shifts to one side and prevents button 36 from being inadvertently pressed. In order to enable button 36 to be depressed, safety button 35 must be pushed back in the opposite direction.
FIG. 2 illustrates cover 25, which may be hinged to housing 24 so as to open in the manner shown. Spring catch 37 (shown in FIG. 3) holds cover 25 in the closed position, but upon moderate upward pressure to cover 25, will deflect sufficiently to release cover 25. Central support 39 is fixably mounted generally along the longitudinal center of housing 24, and generally divides the interior of housing 24 into a forward region and a rearward region. Shaft 40 is arranged for reciprocating axial movement substantially parallel to the longitudinal axis of housing 24, and is mechanically connected to lever 28 by crank 42, which is, in turn, pivotably connected to lever 28 by pin 43 and pivotably connected to shaft 40 by pin 44. Accordingly, when lever 28 is pivoted in the direction indicated by arrow A, shaft 40 moves axially backward with respect to housing 24. Yokes 46 and 47 are each configured to be retained within housing 24 by projecting tabs, such as tab 49 of yoke 46, which are received within longitudinally extending grooves, such as groove 50. Accordingly, yokes 46 and 47 are each configured to be longitudinally, slidably moved relative to support housing 24.
Shaft 40 is configured to pass through yokes 46 and 47, through apertures 23 and 53, respectively. Yokes 46 and 47 are each biased forwardly, with respect to housing 24, by coil springs 55 and 56, respectively. When yoke 46 is drawn toward rear wall 26 of housing 24 during cocking (as described hereinafter), it is engaged and retained adjacent rear wall 26 by retaining member 58. Retaining member 58 is normally biased to pivot in a clockwise direction around axis 59 so that engagement portions 60 of retaining member 58 are normally biased to move upwardly relative to housing 24. Engagement portions 60, which are wedge-shaped, are driven downwardly by pins 61 (as shown in FIG. 3), until pins 61 pass the rear edges of engagement portions 60, as yoke 46 approaches rear wall 26. Once pins 61 have passed the rear edges of engagement portions 60, retaining member 58 is permitted to then rotate clockwise and pins 61 abut the rear edges of engagement portions 60, preventing yoke 46 from being driven forward under the bias of now-compressed spring 55.
FIG. 3 illustrates automatic tissue sampling apparatus 20 with yokes 46 and 47 in their fully cocked positions. Spring 62, which is weaker than either of springs 55 or 56, at one end abuts yoke 47 and at the other end abuts cross member 64. Spring 62, being at all times in a slightly compressed configuration, tends to push cross member 64 and yoke 47 apart, thereby tending to maintain shaft 40 in a forwardly drawn position with respect to, and substantially fully within, housing 24. Shaft 40 is provided with a longitudinally extending recess 65 with sharply defined end surfaces 66 and 67 as shown in FIGS. 5-11.
Yoke 47 is illustrated, in FIG. 3, in its retained position against central support 39. To draw yoke 47 against central support 39, against the bias of spring 56, when lever 28 is actuated, cross member 64 abuts the front edge of yoke 47 and forces yoke 47 backward toward central support 39. Yoke 47 is restrained in that position by retaining member 70, which is arranged for pivotal movement about axis 71. Retaining member 70 includes engagement portions 72, which engage pin 73 (see, for example, FIG. 5) in substantially the same manner as engagement portions 60 of retaining member 58 engage pins 61 of yoke 46. Retaining member 70 is, like retaining member 58, biased to pivot toward the clockwise direction (as seen in FIG. 3) and engagement portions 72 are wedge-shaped so that as yoke 47 approaches central support 39, pins 73 force retaining member 70 to pivot counter-clockwise, slightly, until pins 73 ride over and past engagement portions 72.
In order to permit the cocking of automatic tissue sampling apparatus 20, without having to overcome the combined force of both of springs 55 and 56, and as well to permit the inspection of the tissue sample once the sample has been taken (in a manner described hereinafter), the automatic tissue sampling apparatus 20 has been provided with a tissue sample inspection feature and is configured so that yokes 46 and 47 are cocked and retained against springs 55 and 56, respectively, during separate, successive actuations of lever 28. Specifically, yoke 46 is configured to normally be freely, axially movable relative to shaft 40 (aside from the biasing force of spring 55). However, catch member 74 is pivotably supported about pin 75 in a forward portion of yoke 46. Catch member 74 is biased, by spring 76, for example, in a clockwise direction upwardly away from shaft 40. However, yoke 47 is provided with rearwardly projecting pin 78 which, when yoke 47 has been drawn backward against central support 39, projects through a horizontally extending aperture (not shown) in central support 39 to depress catch member 74 downwardly toward shaft 40 so that the forwardmost edge of catch member 74 is held against the bottom of recess 65, as illustrated in FIG. 7. When lever 28 has been actuated again, the forward edge of catch member 74 abuts and is caught by the forward edge 7 of recess 65 and shaft 40, thereby pushing yoke 46 backward toward rear wall 26 and retaining member 58.
Yoke 47 additionally has rearwardly projecting pin 140 (see FIGS. 2, 3 and 4), which also is configured to pass through a horizontally extending aperture (not shown) in and extend beyond central support 39, even when yoke 47 is positioned immediately adjacent central support 39. A bore 141 is provided in the forward face of yoke 46, which is aligned to receive pin 140. Spring 142 is arranged to snugly fit within bore 141. The strength and stiffness of spring 142 is sufficient such that when pin 140 projects into bore 141, under the impulse of spring 46, spring 142 will yield slightly and then resist further compression, so that yoke 46 will be forced away from central support 39, as yoke 47 is driven to and retained substantially adjacent central support 39.
The release of prior art yoke 46 is accomplished by pressing button 36, which pushes forward the upper end of the vertical portion of retaining member 58, simultaneously causing engagement portions 60 of retaining member 58 to pivot downwardly to remove the obstruction of pins 61 of yoke 46. Propelled by the force of spring 55, yoke 46 moves forward rapidly. Contact is first made between spring 142 in bore 141, and pin 140. Immediately, due to the stiffness of spring 142, yoke 46 begins to decelerate, although it continues to approach central support 39. As yoke 46 continues to approach central support 39, secondary button 83 contacts rearward end 84 of retaining member 70. When pushed by secondary button 83, retaining member 70 pivots against the bias of spring 79 (as shown in FIGS. 5-11), causing engagement portions 72 of retaining member 70 to remove the obstruction of pins 73 of yoke 47. Yoke 47 is thereby released, and is propelled by spring 56 toward the front end of apparatus 20. Substantially simultaneously, the forward face of yoke 46 encounters bumper 80. As yoke 47 recedes, the reactive force produced by the combination of pin 140 and spring 142 is lessened, and yoke 46 is brought to a smooth halt against bumper 80, with no rebound, and significantly reduced noise and jarring. Accordingly, when button 36 is pressed, yokes 46 and 47 are released consecutively in rapid succession.
It has been noted that the prior art apparatus of FIGS. 1-12 has provided the additional advantage of a slightly prolonged exposure of the tissue holding region, as compared to the apparatus disclosed in Ser. No. 07/753,602, now U.S. Pat. No. 5,284,156. This slightly prolonged exposure, together with the still further reduction in shock during sampling, has permitted a greater volume of tissue to occupy the tissue holding region, before capture, resulting in greater accuracy of location and an improved tissue sample.
As previously mentioned, the automatic tissue sampling apparatus 20 of FIGS. 1-12 was configured to be used with a conventional two-needle biopsy needle system 22 (having two separate large handles), the general configuration of which is well known from the prior art. Biopsy needle system 22 is composed of two parts, first needle 86 and second needle 96. First needle 86 consists of substantially solid shaft 87 with integrated handle 88. Angled point 89 is positioned at the end of shaft 87, opposite from handle 88, to facilitate insertion of the needle system into the tissue to be sampled. Proximate to point 89, tissue holding region 90 is cut-out from shaft 87, as illustrated in FIG. 6. When biopsy needle system 22 is inserted into a tissue to be sampled, and tissue holding region 90 is exposed, a portion of the tissue moves into tissue holding region 90, and is sheared off and retained there as the desired sample.
Shaft 87 is freely inserting received by hollow shaft 97 of second needle 96, with integrated handle 98. An aperture (not shown) extends through the length of handle 98. Handles 88 and 98 are typically additionally configured to be asymmetrical, particularly with tabs 92, and 99a and 99b, which have portions projecting perpendicularly from handles 88 and 98, respectively. As the length of shaft 87 exceeds the combined length of hollow shaft 97 and handle 98, point 89, at substantially all times during normal use, is exposed.
The operation of prior art biopsy needle system 22, to obtain and retrieve a tissue sample, is as follows. When point 89 is inserted into a tissue, first needle 86 and second needle 96 must be in the configuration shown in FIG. 5, that is, with second needle 86 moved forwardly relative to first needle 86, so that hollow shaft 97 covers tissue holding region 90 of shaft 87, but point 89 remains forwardmost and exposed.
Once first needle 86 and second needle 96 have been inserted into the tissue, first needle 86 is moved forward, with respect to second needle 96, further into that particular region of the tissue, from which a sample is to be retrieved. During this step, second needle 96 is to be stabilized, with respect to the patient and the tissue, for accuracy and for the comfort of the patient.
As point 89 of first needle 86 proceeds further into the tissue, tissue holding region 90 becomes exposed. Since the tissue is not a rigid medium, a portion of the tissue “flows” to fill in, at least partially, tissue holding region 90. To retrieve and remove the sample, second needle 96 is then rapidly thrust forward, relative to first needle 86, which, in turn, is stabilized relative to the patient and the tissue—to eventually shear off and enclose the tissue that had previously flowed into tissue holding region 90.
As illustrated in FIGS. 5 through 11, hollow shaft 97 is also provided with point 100, which is also angled so that the extreme tip 101 of point 100 is positioned, when first needle 86 and second needle 96 are aligned, on the side of the shaft 15 in which tissue holding region 90 is formed. Proper alignment of first needle 86 and second needle 96 is obtained when the projecting portions of tabs 92, 99a and 99b are aligned.
Accordingly, as second needle 96 is moved forward relative to first needle 86, extreme tip 101 cuts the tissue to leave a portion of the tissue within tissue holding region 90. As second needle 96 continues to move forward, the tissue sample and tissue holding region 90 are covered. At this point, first needle 86 and second needle 96 have resumed the relative positions indicated by FIG. 5 and must be withdrawn from the patient together in that position, in order to prevent the tissue sample from being dislodged or contaminated by other tissue.
To accomplish such operations with precision, speed and a minimum of discomfort to the patient, using manual methods, is extremely difficult. Prior art automatic tissue sampling apparatus 20 has enabled the foregoing procedure to be accomplished swiftly, with a substantially reduced level of discomfort to the patient, and with a high degree of repeatability of result from one procedure to the next.
FIGS. 5 through 11 illustrate the successive steps in the operation of the prior art automatic tissue sampling apparatus 20. In FIG. 5, automatic tissue sampling apparatus 20 is shown in an uncocked configuration. Hollow shaft 97 of second needle 96 covers tissue holding region 90 of first needle 86. A first actuation of lever 28 causes cross member 64 to abut the front face yoke 47, driving yoke 47 against the force of spring 56, into position to be retained by retaining member 70. This procedure draws second needle 96 backward relative to first needle 86, thus exposing tissue holding region 90. As previously described, once yoke 47 has been drawn back and retained by retaining member 70, pin 78 depresses catch member 74 against the bias of spring 76. Accordingly, when lever 28 is returned to its lowered position, returning shaft 40 to its fully forward position, catch member 74 is forced into recess 65.
In addition, during the first actuation of lever 28, as yoke 47 approaches central support 39, pin 140 passes through central support 39 and contacts spring 142 within bore 141. Spring 142 compresses slightly and then resists further compression, causing yoke 46 to be forced away from central support 39, as described earlier.
A subsequent actuation of lever 28, again draws back shaft 40. However, leading edge 67 of recess 65 pushes on catch member 74 to force yoke 46 further backward toward retaining member 58. The upper end of retaining member 58 simultaneously pushes button 36 backward relative to rearward projecting portion 33 of housing 24. Returning lever 28 to its initial position again places automatic tissue sampling apparatus 20 into a configuration ready for insertion of biopsy needle system 22 into the tissue to be sampled, or resampled, if required.
Due to the power and speed with which the yokes 46 and 47 are propelled forward, respectively, by springs 55 and 56, once button 36 is depressed, and in view of the hazardous nature of the biopsy needle system, it is highly desirable to provide automatic tissue sampling apparatus 20 with an automatically deployed safety mechanism to prevent actuation of automatic tissue sampling apparatus 20. The prior art apparatus of FIGS. 1-12 has been provided with such a safety mechanism, in part illustrated in FIG. 12.
FIG. 12 shows shaft 40 and safety button 35. Shaft 40 has arranged, upon an upper surface thereof, cam surface 110. Button 36 is formed in three parts, forward large diameter portion 120, central narrow portion 121, and rearward large diameter portion 122. Safety button 35 is configured as a substantially cylindrical rod having, on an upper surface thereof, an arcuate depression 111 formed thereon and extending substantially longitudinally along the axis of safety button 35. Safety button 35 is disposed parallel to the transverse axis of housing 24, for limited reciprocal movement in an aperture in projection 33. Upon the lower half of safety button 35, a recess is carved out having a depth substantially equal to the depth of cam surface 110 and having a width slightly greater than the width of shaft 40. When shaft 40 is in its forwardmost position within housing 24, as shown in FIG. 5, shaft 40 occupies the position, relative to safety button 35, indicated by the solid line button 35 in FIG. 12. As illustrated, recesses 111 and 112 are slightly offset in the transverse direction. Recess 111, when positioned relative to shaft 40 as shown in the solid line figure in FIG. 12, enables the rearward large diameter portion 122 of button 36 to pass over safety button 35, enabling button 36 to move forwardly sufficiently to pivot retaining member 58 and release yoke 46.
When lever 28 is cocked, shaft 40 is automatically moved in the direction of the arrow B in FIG. 12 and cam surface 110 forces safety button 35 to move in the direction of arrow C and thus occupy the position, relative to the shaft 40, shown as 35′. When lever 28 is returned to its lower position, shaft 40 moves forward again relative to housing 24. While recess 112 is at that time positioned over the widest part of cam surface 110, safety button 35 is held by friction in its safety position, with recess 111 offset to one side of shaft 40. Accordingly, if button 36 is depressed, the rearward large diameter portion 122 of button 36 abuts and is blocked by safety button 35. Only when safety button 35 is pushed in the direction opposite arrow C in FIG. 12, so that recess 111 again becomes aligned with shaft 40, can button 36 be fully depressed, to actuate apparatus 20.
Once prior art biopsy needle system 22 has been positioned in the patient and into the particular tissue to be sampled, and safety button 35 moved to release button 35, automatic tissue sampling can be effectuated. FIG. 10 illustrates automatic tissue sampling apparatus 20 in a configuration only a split second after button 36 has been fully depressed. Retaining member 58 has been pivoted counter-clockwise, with engagement surfaces 60 no longer obstructing pins 61. Yoke 46 is moving rapidly toward central support 39 under the impetus of spring 55. Shaft 87 of first needle 86 is being propelled forward relative to hollow shaft 97 of second needle 96. Tissue holding region 90 is being exposed. Pin 140 connects with spring 142 (not shown in FIGS. 5-11) and causes yoke 46 to slow down in its forward movement. Yoke 46 continues forward, and secondary button 83 reaches retaining member 70 and causes it to rotate counterclockwise, as illustrated in FIG. 11. Engagement surfaces 72 of retaining member 70 clear pins 73 and thus yoke 47 is propelled forward by spring 56. Second needle 96 is brought forward so that shaft 97 covers tissue holding region 90 of first needle 86. Yoke 46 is brought to rest against bumper 80.
The first and second needles 86 and 96 respectively, are held together to facilitate removal of biopsy needle system 22 from the tissue being sampled. Once removed from the patient, it is often desirable to inspect the tissue holding region 90, in order to determine whether a sample has been successfully taken and, if so, to enable deposit of the sample onto a microscope slide, or other appropriate receptacle. Inspection of tissue holding region 90 is easily accomplished in the present invention-by merely applying a single stroke to actuating lever 28 after it has been fired, in order to draw back second needle 96, as illustrated in FIG. 6. If a suitable sample has not been retrieved, after inspection, a second actuation of lever 28 draws back first needle 86, and places the automatic tissue sample apparatus again in a fully cocked configuration, ready for the reinsertion of biopsy needle system 22 into the tissue to be sampled.
An additional advantage of the construction of the prior art apparatus of FIGS. 1-12, is that the provision of pin 140, spring 142, and bumpers 80 and 130 prevent actual contact between yokes 46 and 47, and central support 39 and forward wall 131, which tend to reduce the noise otherwise associated with such apparatus. In addition, the deceleration produced by these elements tends to reduce the “shock” which may be felt when apparatus 20 is actuated. Noise and shock are further reduced by fabricating bumpers 80 and 130 from resilient compressible plastic or rubber material, and by fabricating yokes 46 and 47 from nylon or similar materials. By reducing noise and shock, the patient's discomfort, actual and/or perceived, during the sampling procedure, was reduced.
FIGS. 13-15 illustrate an alternative prior art automatic tissue sampling apparatus. While the previously described embodiments comprise improvements over the prior art, the embodiment of FIGS. 13-15 comprised an even further improvement over the prior art. It has been observed that manipulation of the previously described embodiments can, on occasion, be complex, in that the physician or medical technician who is operating the device, typically grasps an apparatus 20 at the front end of housing 24, while the end of needle 22 is being positioned into a patient. The grasping is typically done one-handed, as the operator is typically holding an ultrasonic sender-sensor in the other hand, while observing placement of the end of needle 22 on the display of the ultrasonic device. Once the end of the needle has been positioned, then the operator must shift his grip on apparatus 20, in order to reach firing button 36 to fire apparatus 20. The shifting of the grip is not only inconvenient to the operator, it can cause shifting of the positioning of the end of the needle 22, within the patient, both compromising the accuracy of the tissue sampling, and possibly causing additional discomfort to the patient.
In yet other uses, the device is placed into a staging fixture, which grips the apparatus at various locations, and which often requires manipulation or adjustment toward the front of the apparatus.
Prior art apparatus 150 is operably configured to alleviate the aforementioned potential problems presented by the required shifting of grip by an operator. Apparatus 150 includes a front-accessible firing button 152, which enables apparatus 150 to be fired, one-handed, or from within a staging fixture—without the operator having to shift grip after completing placement of the end of needle 22, and without inadvertent movement of the fixture. The location and recessing of the front accessible firing button 152 simultaneously avoids inadvertent actuation by the clamping elements of a staging fixture.
While in the illustrated embodiment, apparatus 150 has both rear firing pin 36 as well as front firing button 152, in yet another embodiment, rear firing pin 36 may be replaced with a shortened member which does not project outwardly from the rear of apparatus 150, such that actuation of apparatus 150 may only be accomplished by front firing button 152.
The cocking, firing and safety mechanisms disclosed in FIGS. 1-12 are present in prior art apparatus 150, in substantially unmodified form, and so are only partially illustrated in phantom outline in FIGS. 13-15. Yokes 46 and 47 are representatively illustrated in their respective forward positions, although other constructions for contacting and propelling the handles of the needle apparatus may be employed. Apparatus 150 includes a modified front plate 154, having apertures 156 and 158, and rounded depression 160 into which firing button 152 may be depressed.
Firing button 152 is formed from the externally exposed transverse portion of J-shaped firing member 162. Longitudinal portion 164 of firing member 162 extends along the interior of housing 166 of apparatus 150, preferably in an appropriately configured channel or groove, such as channel 168, to the side and out of the way of the movable yokes, in which are to be seated the handles of the needle apparatus.
Interconnection arm 170 is pivotably mounted on pin 172. Lower end 174 of interconnection arm 170 is, in turn, pivotably connected to end 176 of firing member 162. Lateral pin 178 emanates horizontally from upper end 180 of interconnection arm 170, and is operably positioned so as to be pivotably received in lateral slot 182 in rear firing pin 184, which is otherwise configured to be substantially identical to firing pin 36 described with respect to the previous embodiment.
In the prior art embodiment of FIGS. 13-15, after apparatus 150 has been loaded and armed, in the manner described with respect to the previous embodiment, firing button 152 was depressed, causing longitudinal portion 164 to move backwards, away from front plate 154. The lower end 174 of interconnection arm 170 moves away from front plate 154. Interconnection arm 170 is forced to pivot, and lateral pin 178 pushes on the forward inside wall of slot 182, pushing/pulling firing pin 184 forward. Face 186 of firing pin 184 pushes against the top of retaining member 58, causing retaining member 58 to pivot about pin 188. Yoke 46 is thereafter released, and apparatus 150 is actuated in the previously described manner, identical to the manner as if firing pin 184 (36 in the previous embodiment) had been depressed.
There is no significant frictional resistance generated against the movement of any of firing member 162, interconnection arm 170, pin 172, or lateral pin 182, apart from that encountered directly resulting from the resistance of retaining member 58 to release the rear yoke.
It is believed that apparatus 150, which may be fired either with front firing button 152, or, if rear firing pin 184 is provided, rear firing pin 184, has provided an improved operation, particularly for those operators who may grasp apparatus 150 either manually or in a fixture, along the front of housing 166, in that front firing button 152 enables actuation of apparatus 150, without the need of the operator to reposition his/her grip, before firing. Firing button 152 was positioned within rounded depression 160, so as to be substantially flush with the face of front plate 154, so that, when apparatus 150 is armed, a positive inward pushing movement is required to fire apparatus 150, and the likelihood of accidental firing, such as by contact with a flat surface, from the fixture or otherwise, is substantially reduced.
FIGS. 16-34 illustrate a preferred embodiment of the present invention, automatic tissue sampling apparatus 20′, which is substantially similar in general operation to the prior art embodiment of FIGS. 1-12, in terms of the general cocking mechanism and cocking actions, and substantially similar to the prior art embodiment of FIGS. 13-15, in that it is provided with both a forward-firing and rear firing actuator and associated mechanism. Accordingly, structural elements which are the same or similar in structure and operation to analogous structural elements which are shown and described with respect to the prior art embodiments of FIGS. 1-12 and 13-15, are given like references numerals, augmented by a prime (′) in the figures, and those portions of the descriptions of FIGS. 1-12 and 13-15, which are directed to such similarly referenced structures in the embodiment of FIGS. 16-34 should be deemed applicable to the embodiment of FIGS. 16-34.
Automatic tissue sampling apparatus 20′, illustrated in FIG. 16, includes housing 24′ with cover 25′. Automatic tissue sampling apparatus 20′ is cocked using lever 28′, which is provided with thumb rest portion 30′. Lever 28′ is mounted for facilitated pivotal movement around pin 32′. Spring catch 37′ holds cover 25′ in the closed position, but upon moderate upward pressure to cover 25′, will deflect sufficiently to release cover 25′. Central support 39′ is fixably mounted generally along the longitudinal center of housing 24′, and generally divides the interior of housing 24′ into a forward region and a rearward region. Shaft 40′ is arranged for reciprocating axial movement substantially parallel to the longitudinal axis of housing 24′, and is mechanically connected to lever 28′ by crank 42′, which is, in turn, pivotably connected to lever 28′ by pin 43′ and pivotably connected to shaft 40′ by pin 44′. Accordingly, when lever 28′ is pivoted in the direction indicated by arrow A (FIG. 16), shaft 40′ moves axially backward with respect to housing 24′. Yokes 46′ and 47′ are each configured to be retained within housing 24′ by projecting tabs, such as tab 49′ of yoke 46′, which are received within longitudinally extending grooves, such as groove 50′. Accordingly, yokes 46′ and 47′ are each configured to be longitudinally, slidably moved relative to support housing 24′.
In this preferred embodiment of the invention, shaft 40′ is configured to pass through yokes 46′ and 47′, through apertures 23′ and 53′, respectively. Yokes 46′ and 47′ are each biased forwardly, with respect to housing 24′, by coil springs 55′ and 56′, respectively. When yoke 46′ is drawn toward rear wall 26′ of housing 24′ during cocking (as described hereinafter), it is engaged and retained adjacent rear wall 26′ by retaining member 58′. Retaining member 58′ is normally biased to pivot in a clockwise direction around axis 59′ so that engagement portions 60′ of retaining member 58′ are normally biased to move upwardly relative to housing 24′. Engagement portions 60′, which are wedge-shaped, are driven downwardly by pins 61′, until pins 61′ pass the rear edges of engagement portions 60′, as yoke 46′ approaches rear wall 26′. Once pins 61′ have passed the rear edges of engagement portions 60′, retaining member 58′ is permitted to then rotate clockwise and pins 61′ abut the rear edges of engagement portions 60′, preventing yoke 46′ from being driven forward under the bias of now-compressed spring 55′.
Spring 62′ is weaker than either of springs 55′ or 56′. At one end it abuts yoke 47′ and at the other end it abuts cross member 64′. Spring 62′, being at all times in a slightly compressed configuration, tends to push cross member 64′ and yoke 47′ apart, thereby tending to maintain shaft 40′ in a forwardly drawn position with respect to, and substantially fully within, housing 24′. Shaft 40′ is provided with a longitudinally extending recess 65′ with sharply defined end surfaces 66′ and 67′.
Yoke 47′ is illustrated, in FIG. 19, in its retained position against central support 39′. To draw yoke 47′ against central support 39′, against the bias of spring 56′, when lever 28′ is actuated, cross member 64′ abuts the front edge of yoke 47′ and forces yoke 47′ backward toward central support 39′. Yoke 47′ is restrained in that position by retaining member 70′, which is arranged for pivotal movement about axis 71′. Retaining member 70′ includes engagement portions 72′, which engage pin 73′ in substantially the same manner as engagement portions 60′ of retaining member 58′ engage pins 61′ of yoke 46′. Retaining member 70′ is, like retaining member 58′, biased to pivot toward the clockwise direction and engagement portions 72′ are wedge-shaped so that as yoke 47′ approaches central support 39′, pins 73′ force retaining member 70′ to pivot counter-clockwise, slightly, until pins 73′ ride over and past engagement portions 72′.
In order to permit the cocking of automatic tissue sampling apparatus 20′, without having to overcome the combined force of both of springs 55′ and 56′, and to permit the inspection of the tissue sample once the sample has been taken (in a manner described hereinafter), the automatic tissue sampling apparatus 20′ has been provided with a tissue sample inspection feature and is configured so that yokes 46′ and 47′ are cocked and retained against springs 55′ and 56′, respectively, during separate, successive actuations of lever 28′. Specifically, yoke 46′ is configured to normally be freely, axially movable relative to shaft 40′ (aside from the biasing force of spring 55′). However, catch member 74′ is pivotably supported about pin 75′ in a forward portion of yoke 46′. Catch member 74′ is biased, by spring 76′ and pin 76A, for example, in a counterclockwise direction downwardly toward 40′. When yoke 46′ is pushed away from support 39′ (as described below), the vertical face 74A′ of catch member 74′ moves away from pin 78′ (which is biased by spring 78A′ to move slightly, when yoke 46′ bumps into support 39′ during the firing process), permitting catch member 74′ to pivot in the counterclockwise direction. When lever 28′ has been actuated again, the forward edge of catch member 74′ abuts, and is caught by, the forward edge 66′ of recess 65′ and shaft 40′, thereby pushing yoke 46′ backward toward rear wall 26′ and retaining member 58′.
Yoke 47′ additionally has rearwardly projecting pin 140′, which also is configured to pass through a horizontally extending aperture in (and extend beyond) central support 39′, even when yoke 47′ is positioned immediately adjacent central support 39′. A bore 141′ is provided in the forward face of yoke 46′, which is aligned to receive pin 140′. Spring 142′ is arranged to snugly fit within bore 141′. The strength and stiffness of spring 142′ is sufficient such that when pin 140′ projects into bore 141′, under the impulse of spring 46′, spring 142′ will yield slightly and then resist further compression, so that yoke 46′ will be forced away from central support 39′, as yoke 47′ is driven to and retained substantially adjacent central support 39′.
The release of yoke 46′ is accomplished by pressing button 36′, which pushes forward the upper end of the vertical portion of retaining member 58′, simultaneously causing engagement portions 60′ of retaining member 58′ to pivot downwardly to remove the obstruction of pins 61′ of yoke 46′. Propelled by the force of spring 55′, yoke 46′ moves forward rapidly. Contact is first made between spring 142′ in bore 141′, and pin 140′. Immediately, due to the stiffness of spring 142′, yoke 46′ begins to decelerate, although it continues to approach central support 39′. As yoke 46′ continues to approach central support 39′, secondary button 83′ contacts rearward end 84′ of retaining member 70′. When pushed by secondary button 83′, retaining member 70′ pivots against the bias of spring 79′ causing engagement portions 72′ of retaining member 70′ to remove the obstruction of pins 73′ of yoke 47′. Yoke 47′ is thereby released, and is propelled by spring 56′ toward the front end of apparatus 20′. Substantially simultaneously, the forward face of yoke 46′ encounters bumper 80′. As yoke 47′ recedes, the reactive force produced by the combination of pin 140′ and spring 142′ is lessened, and yoke 46′ is brought to a smooth halt against bumper 80′, with no rebound, and significantly reduced noise and jarring. Accordingly, when button 36′ is pressed, yokes 46′ and 47′ are released consecutively in rapid succession.
It has been noted that the apparatus of the present invention provides the additional advantage of a slightly prolonged exposure of the tissue holding region, as compared to the apparatus disclosed in the prior art apparatus disclosed in Ser. No. 07/753,602, now U.S. Pat. No. 5,284,156. This slightly prolonged exposure, together with the still further reduction in shock during sampling, permits a greater volume of tissue to occupy the tissue holding region, before capture, resulting in greater accuracy of location and an improved tissue sample.
The automatic tissue sampling apparatus 20′ of the present invention is configured to be used with a conventional two-needle biopsy needle system such as that disclosed in Terwilliger, U.S. Pat. No. 6,110,129 (the complete disclosure of which is hereby expressly incorporated herein by reference), and a version of which has been previously marketed and sold under the mark Pro-MagTM I 2.2 and versions of which are presently being marketed and sold under the marks Pro-Mag UltraTM and Pro-Mag Ultra STTM, by Inter-V Manan. Such a needle system is shown in perspective view in FIG. 35. Although this system has a somewhat differently configured handle structure, from the prior art needle system shown in FIGS. 2-11, the functional and dynamic relationships between the inner and outer needles and their respective handles, during the cocking and firing processes are the same. One may simply make reference to the movement steps described with respect to FIGS. 5-11, to readily understand how the needle system for the embodiment of FIGS. 16-34 operates. In particular, with the automatic tissue sampling apparatus in the configuration shown in FIG. 17, a needle system is inserted, and the cover closed. After two successive cocking motions of handle 28′, the apparatus is ready for positioning of the needle tip at the site to be sampled, and can be fired to effect the sampling procedure.
Due to the power and speed with which the yokes 46′ and 47′ are propelled forward, respectively, by springs 55′ and 56′, once button 36′ is depressed, and in view of the hazardous nature of the biopsy needle system, it is highly desirable to provide automatic tissue sampling apparatus 20′ with an automatically deployed safety mechanism to prevent actuation of automatic tissue sampling apparatus 20′. The present invention is provided with such a safety mechanism, in part illustrated in FIGS. 18, 19, 26 and 34.
Like the embodiment of FIGS. 13-15, the embodiment of FIGS. 16-34 is provided with a forward-firing mechanism, which is substantially, if not entirely, identical to that illustrated in and described with respect to FIGS. 13-15.
Apparatus 20′ includes a front-accessible firing button 152′, which enables apparatus 20′ to be fired, one-handed, or from within a staging fixture—without the operator having to shift grip after completing placement of the end of the needle system, and without inadvertent movement of the fixture. The location and recessing of the front accessible firing button 152′ simultaneously avoids inadvertent actuation by the clamping elements of a staging fixture.
Apparatus 20′ includes a modified front plate 154′, having apertures 156′ and 158′, and rounded depression 160′ into which firing button 152′ may be depressed.
Firing button 152′ is formed from the externally exposed transverse portion of J-shaped firing member 162′. Longitudinal portion 164′ of firing member 162′ extends along the interior of 24′ of apparatus 20′, preferably in an appropriately configured channel or groove, to the side and out of the way of the movable yokes, in which are to be seated the handles of the needle apparatus.
Interconnection arm 170′ is pivotably mounted on pin 172′. Lower end 174′ of interconnection arm 170′ is, in turn, pivotably connected to end 176′ of firing member 162′. Lateral pin 178′ emanates horizontally from upper end 180′ of interconnection arm 170′, and is operably positioned so as to be pivotably received in lateral slot 182′ in rear firing pin 36′, which is configured to be substantially identical to firing pin 184 described with respect to the embodiment of FIGS. 13-15.
In this preferred embodiment, after apparatus 20′ has been loaded and armed, in the manner described with respect to the previous embodiment, firing button 152′ is depressed, causing longitudinal portion 164′ to move backwards, away from front plate 154′. The lower end 174′ of interconnection arm 170′ moves away from front plate 154′. Interconnection arm 170′ is forced to pivot, and lateral pin 178′ pushes on the forward inside wall of slot 182′, pushing/pulling firing pin 36′ forward. Face 186′ of firing pin 36′ pushes against the top of retaining member 58′, causing retaining member 58′ to pivot about pin 59′. Yoke 46′ is thereafter released, and apparatus 20′ is actuated in the previously described manner, identical to the manner as if firing pin 36′ had been depressed.
In a preferred embodiment of the invention, there is no significant frictional resistance generated against the movement of any of firing member 162′, interconnection arm 170′, pin 172′, or lateral pin 182′, apart from that encountered directly resulting from the resistance of retaining member 58′ to release the rear yoke.
It is believed that apparatus 20′, which may be fired either with front firing button 152′, or, if rear firing pin 36′ is provided, with rear firing pin 36′, provides an improved operation, particularly for those operators who may grasp apparatus 20′ either manually or in a fixture, along the front of housing 24′, in that front firing button 152′ enables actuation of apparatus 150′, without the need of the operator to reposition his/her grip, before firing. Firing button 152′, in a preferred embodiment of the invention, is positioned within rounded depression 160′, so as to be substantially flush with the face of front plate 154′, so that, when apparatus 20′ is armed, a positive inward pushing movement is required to fire apparatus 20′, and the likelihood of accidental firing, such as by contact with a flat surface, from the fixture or otherwise, is substantially reduced.
There are significant differences between the apparatus of FIGS. 1-12 and that of FIGS. 16-34. For example, referring to FIG. 18, pin 76A is prompted by spring 76′ to push catch member 74′ downwardly, toward and into recess 65′ during the cocking process. Similarly, catch member 74′ is prompted out of recess 65′ during the cocking process by pin 78′ which is prompted toward catch member 74′ by spring 78A′. Furthermore, sampling apparatus 20′ is configured to use double-needle biopsy needles such as those disclosed in Terwilliger, U.S. Pat. No. 6,110,129, which have integrated, sliding handles, which, while different in appearance, are configured to move, relative to one another in substantially the same manner as the needle construction shown with respect to the embodiments of FIGS. 1-12 and 13-15. Accordingly, sampling apparatus 20′ is provided with yokes 46′ and 47′ which are provided with a somewhat different construction than yokes 46 and 47 of the embodiment of FIGS. 1-12, or of FIGS. 13-15.
Amongst these significant differences, the improved safety lock construction of the embodiment of FIGS. 16-34 is shown in particular in FIGS. 18, 19, 26 and 34. FIG. 34 shows shaft 40′ and safety button 35. Shaft 40′ includes notch 110′. Firing button 36′ is formed in four parts, forwardmost narrow portion 123′, with transverse notch 124′, forward large diameter portion 120′, central narrow portion 121′, and rearward large diameter portion 122′ (see FIG. 19). Safety button 35′ is configured as a substantially cylindrical rod having, on an upper surface thereof, an arcuate depression 111′ formed thereon and extending substantially longitudinally along the axis of safety button 35′. Safety button 35′ is disposed parallel to the transverse axis of housing 24′, for limited reciprocal movement in an aperture in projection 33′. Upon the lower half of safety button 35′, a recess is carved out having a depth substantially equal to the depth of notch 110′ and having a width slightly greater than the width of shaft 40′. When shaft 40′ is in its forwardmost position within housing 24′, shaft 40′ occupies the position, relative to safety button 35′, indicated by the solid line button 35′ in FIG. 34. As illustrated, recesses 111′ and 112′ are slightly offset in the transverse direction. Recess 111′, when positioned relative to shaft 40′ as shown in the solid line figure in FIG. 34, enables the rearward large diameter portion 122′ of button 36′ to pass over safety button 35′, enabling button 36′ to move forwardly sufficiently to pivot retaining member 58′ and release yoke 46′.
In order to enable lever 28′ be cocked, safety button 35′ must be moved from a right hand position (relative to the operator when the apparatus 20′ is being held by the operator at the rear of the device, and facing the device), which is the solid line position shown in FIG. 34, to a left hand position, which is the broken line position 35′′ shown in FIG. 34. When lever 28′ is returned to its lower position, shaft 40′ moves forward again relative to housing 24′. Accordingly, if button 36′ is depressed, the rearward large diameter portion 122′ of button 36′ abuts and is blocked by safety button 35′. Only when safety button 35′ is pushed in the direction opposite arrow C in FIG. 34, so that recess 111′ again becomes aligned with shaft 40′, can button 36′ be fully depressed, to actuate apparatus 20′. Because notch 110′ has a length which is only slightly greater than the diameter of that portion of button 35′ which engages it, when button 35′ has been pushed to the right (opposite the direction of arrow C), it is impossible to pull lever 28′ upwardly any significant distance would could result in misalignment of the components in apparatus 20′ during the firing action, which could in turn result in misfiring or internal damage to the apparatus 20′.
As mentioned, when the sampling apparatus 20′ is at its “at-rest”, uncocked configuration, safety button 35′ may be substantially freely slid from one side to the other. In order to provide some slight resistance to lateral movement, button 35′ is provided with two depressions 160′, 162′. Spring 176′ mounted in a bore in housing 24′ prompts ball 164′ toward button 35′. Depressions 160′, 162′ represent the “on” and “off” positions of the safety button 35′. The force exerted by spring 176′ and ball 174′, when ball 174′ is seated in one of depressions 160′ or 162′ is sufficient to prevent button 35′ from simply sliding free (if, for example, apparatus 20′ is tilted from one side to the other) to prevent inadvertent setting or releasing of the safety lock mechanism, but not so forceful as to make shifting of button 35′ difficult. Simply put, when the safety button is in the first position, shown in solid lines in FIG. 34, one can operate the rear firing member but cannot operate the cocking lever. Alternatively, when the safety button is in the second position, shown in broken lines in FIG. 34, one can operate the cocking lever, but cannot depress the rear firing member.
While the safety lock of the present invention has been disclosed with respect to the apparatus of FIGS. 16-34, which uses a particular needle system, being that shown in Terwilliger, U.S. Pat. No. 6,110,129, it is to be understood that the safety lock structures may be adapted to other automatic tissue sampling apparatus, which employ different needle systems, such as the automatic tissue sampling apparatus disclosed in Schramm et al., U.S. Pat. No. 5,284,156; Schramm et al., U.S. Pat. No. 5,476,101; and Schramm et al., U.S. Pat. No. 5,507,298, wherein needle systems having larger, discrete handles are employed.
The foregoing description and drawings merely explain and illustrate the invention and the invention is not limited thereto except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

## Claims

1. An automatic tissue sampling apparatus, for use with a biopsy needle system of the kind including a first needle having a shaft member and two ends, a first handle disposed at one end of the shaft member, a cutting point disposed at the other end of the shaft member, and a tissue holding region positioned between the cutting point and the first handle, and a second needle having a hollow shaft, a cutting point disposed at one end of the hollow shaft, a second handle with a passageway arranged therethrough for reciprocation of the first needle, the automatic tissue sampling apparatus comprising:
a housing;
first and second handle holders, operably disposed in the housing, for receiving and holding the first and second handles, respectively, of the first and second needles, toward moving same;
a propulsion mechanism, operably disposed in the housing, for moving the first and second handle holders within the housing, so as to move the respective needle handles to expose and subsequently cover, the tissue holding region, when the biopsy needle system has been positioned at a desired location within a tissue to be sampled, the propulsion mechanism being operably biased so as to tend to move the handle holders so as to expose and subsequently cover the tissue holding region, unless the handle holders are restrained;
a cocking mechanism, for placing the first and second handle holders, and, in turn, the first and second needles of the biopsy needle system respectively, into suitable respective positions within the housing for subsequent movement by the propulsion mechanism, the cocking mechanism including a single cocking lever, successive actuations of which move the first and second handle holders, successively, into said suitable respective positions within the housing for subsequent respective movement by the propulsion mechanism;
a retaining mechanism, for holding the handle holders, and, in turn, the first and second needles of the biopsy needle system in the suitable respective positions within the housing, prior to actuation of the apparatus;
a release mechanism, for actuating the retaining mechanism, so as to release the handle holders and enable the propulsion mechanism to move the first and second needles, so as to expose, and subsequently cover the tissue holding region,
a firing mechanism, operably connected to the release mechanism, for causing the actuation of the propulsion mechanism; and
a safety lock mechanism, incapable of automatic deployment by movement of either the cocking or firing mechanisms,
said safety lock mechanism being operably interconnected between the firing mechanism and the cocking mechanism, said safety lock mechanism being operably configured for movement by direct manual manipulation between a first position, wherein the firing mechanism can only be actuated when the cocking mechanism is substantially immobilized and a second position wherein the cocking mechanism can only be actuated when the firing mechanism is substantially immobilized.

2. The automatic tissue sampling apparatus according to claim 1, wherein the cocking mechanism comprises:
a cocking shaft, mounted in the housing for longitudinal reciprocating movement therein, and operably interconnected with the handle holders; and
said cocking lever being pivotably mounted on a rear wall portion of the housing, proximate the firing mechanism, and connected to the cocking shaft so that upon upward pivoting of the cocking lever, the cocking shaft is drawn rearwardly relative to the housing.

3. The automatic tissue sampling apparatus according to claim 2, wherein the safety lock mechanism comprises:
a safety button, mounted in the rear portion of the housing, for reciprocating movement in a direction transverse to the cocking shaft between first and second positions,
the safety button having engagement structures disposed thereon, configured for selective engagement with the cocking shaft, when the safety button is in its first position, and with the rear firing member, when the safety button is in its second position, so that when the safety button is in its first position, the cocking shaft and, in turn, the cocking lever, are precluded from movement, and when the safety button is in its second position, the firing button is precluded from movement.

4. The automatic tissue sampling apparatus according to claim 3, wherein the safety button has a first notch, with an engagement shoulder therein, operably configured to enable the cocking shaft to move relative to the safety button when the safety button is in its second position, and to engage with a shoulder disposed on the cocking shaft to prevent movement of the cocking shaft relative to the safety button, when the safety button is in its first position.

5. The automatic tissue sampling apparatus according to claim 3, wherein the safety button has a second notch, operably configured to enable the rear firing button to move, when the safety button is in its first position, and to engage with a shoulder disposed on the rear firing button, to preclude movement thereof, when the safety button is in its second position.

6. The automatic tissue sampling apparatus according to claim 1, wherein the firing mechanism comprises:
a rear firing member operably positioned on a rearward portion of the housing.

7. The automatic tissue sampling apparatus according to claim 1, further comprising:
a front firing member operably positioned on a forward portion of the housing, the front firing member being operably interconnected with the rear firing member.