Disposable soft tissue biopsy apparatus

• US 5,036,860 A
• Filed: 11/24/1989
• Issued: 08/06/1991
• Est. Priority Date: 11/24/1989
• Status: Expired due to Term

• Current Assignee: Medical Device Technologies, Inc. (Angiotech Pharmaceuticals Incorporated)
• Original Assignee: Medical Device Technologies, Inc. (Angiotech Pharmaceuticals Incorporated)
• Inventors: Leigh, Harold G., Bourassa, Hugh A., O'Dell, David L.
• Primary Examiner(s): Shay, Randy Citrin
• Application Number:
  US07/440,647
• Time in Patent Office: 620 Days
• Field of Search: 128/305, 128/749, 128/751, 128/752, 128/753, 128/754, 606/167, 606/170, 606/171
• US Class Current: 600/567
• CPC Class Codes: A61B 10/0275 with sample notch, e.g. on the side of inner stylet
• CPC Class Codes: A61B 2010/0208 Biopsy devices with actuators, e.g. with triggered spring mechanisms

Abstract

Soft tissue biopsy apparatus (10) for obtaining a tissue specimen. An elongate housing (12) has an opening (20) at one end (14). A hollow cannula (26) is positioned within the housing, is reciprocally movable therewithin, and one end (28) of the needle extends through the opening for insertion into tissue (T) from which a specimen is to be taken. A needle (44) is positioned within the cannula, is reciprocally movable therewithin, and also has an end (46) extending through the opening for insertion into the tissue. This needle has a recess (50) adjacent its outer end in which a tissue specimen is captured. The needle is connected to a slide (68) by which the needle is moved independently of the cannula. A sleeve (110) installed over the housing is manually operable to move the slide to a selected and cocked position prior to insertion of the cannula/needle into the tissue. Movement of the slide moves the second needle from a first position to a second position while the cannula remains stationary. A release mechanism (114) operable by the user after insertion of the assembly into the tissue initially returns the needle to its first position and then moves the cannula from a first position to a second position. Movement of the cannula to its second position causes the end of the said cannula to cover the end of the needle to capture the tissue speciment within the recess.

Claims

1. A soft tissue biopsy apparatus incorporating a cannula means and a needle means for obtaining a tissue specimen comprising:

an elongate housing having an opening at the front end thereof;

a hollow cannula means positioned within said housing, and reciprocally movable therewithin, one end of said cannula means extending through said opening for insertion into tissue from which a specimen is to be taken;

a needle means positioned within said cannula means and reciprocally movable therewithin, said needle means also having an end extending through said opening for insertion into the tissue and a sampling means adjacent said end in which a tissue specimen is capturable;

slide means to which the needle means is operably connected and capable of moving said needle means independently of said cannula means;

cocking means manually operable by a user of the apparatus for moving the slide means to a selected position prior to insertion of said cannula means and needle means into the tissue, whereby rearward movement of said slide means shifts said needle means and said cannula means from a first position to a second position;

release means operable by the user after insertion of said cannula means and needle means into the tissue for initially returning said needle means to its first position and for then moving said cannula means relative to said needle means towards said first position, and movement of the cannula means into a position causing the end of the cannula means to cover the sampling means of the needle means whereby the tissue specimen is captured between said cannula means and needle means;

spring means providing a force biasing the cannula means and needle means to their respective first positions, and a motive force for moving the respective means upon operation of the release means;

said cannula means including a cannula assembly and the needle means including a stylet assembly;

said cannula assembly including a cannula, a pedestal at one end to which the cannula is connected and from the other end of which a concentric, hollow extension of the cannula extends; and

the stylet assembly including a stylet, a base to which one end of the stylet is attached, and means interlocking with the pedestal to limit movement of the cannula assembly.

2. The apparatus of claim 1 wherein the sampling means comprises a recess formed adjacent the end of the stylet extending through the end of the housing.

3. The apparatus of claim 1 wherein the pedestal has a tongue formed thereon and the interlocking means comprises a bail having legs extending from the base parallel to the stylet with the outer end of the bail fitting over the tongue whereby the distance the stylet assembly is movable substantially corresponds to the height of the bail.

4. The apparatus of claim 3 wherein the spring means comprises a first spring insertable in the housing and fitting between the inner front end of the housing and the face of the pedestal facing that end of the housing, said first spring functioning as a buffer and biasing the cannula assembly toward the opposite end of the housing.

5. The apparatus of claim 4 wherein said slide means includes a hollow slide having a front end in which the base of the stylet assembly is inserted and means for holding the base therein.

6. The apparatus of claim 5 wherein the spring means comprises a second spring seated against the back end of the slide and bearing against said base to urge it against said holding means.

7. The apparatus of claim 6 wherein said housing includes at least one longitudinal guide slot in the side thereof and the slide includes a finger extending outwardly from the side of the slide through said slot.

8. The apparatus of claim 7 wherein the spring means includes a third primary spring seated against the rear end of the housing and bearing against the slide to urge it toward the front end of the housing.

9. The apparatus of claim 8 wherein the cocking means includes a cylindrical sleeve slidingly installed over the housing for moving the slide rearwardly in the housing against the force of the said third spring.

10. The apparatus of claim 9 wherein the sleeve has a tab contacting the finger as the sleeve is moved rearwardly of the housing, said tab moving said finger in said guide slot to draw the slide rearwardly against the force of the third spring to cock the apparatus, said stylet moving from said first position to said second position as said slide moves, the recess in said stylet being withdrawn into the cannula as the apparatus is cocked.

11. The apparatus of claim 10 wherein the housing has a longitudinal cocking slot in the side thereof and the sleeve has a pin insertable in said slot, said pin moving in said cocking slot as said sleeve is moved rearwardly, said cocking slot having a turned nose at the rearward end thereof in which the pin is received when the apparatus is fully cocked.

12. The apparatus of claim 11 wherein the housing includes a pair of opposed longitudinal cocking slots in the side and the sleeve has a pin insertable in each cocking slot, each said pin moving in its respective cocking slot as said sleeve is moved rearwardly, and each said cocking slot having a turned nose at the rearward end thereof in which the pins are received when the apparatus is fully cocked to lock the sleeve in place.

13. The apparatus of claim 11 wherein the release means comprises a pushbutton on the side of the sleeve for pressing the finger inwardly into the housing after the cannula means and needle means have been inserted into the tissue and positioned proximate the area from which the specimen is being taken, inward movement of the finger releasing the finger from the tab whereby said third primary spring propels the slide forwardly and moves the stylet assembly from its set position to its first position, the recess in the end of the stylet being uncovered by the movement thereof.

14. The apparatus of claim 13 further including stop means extending transversely of the housing for limiting forward movement of the stylet assembly.

15. The apparatus of claim 14 wherein the stop means includes a pin having a center slot extending transversely of the housing, the legs of the bail of the stylet extending through the center slot and the width of the center slot being less than the width of the stylet assembly base.

16. The apparatus of claim 15 wherein the housing has a longitudinal base guide slot in the side thereof and the stopping means further includes a pin received in the base and fitting into the guide slot.

17. The apparatus of claim 15 wherein the slide has opposed longitudinal slots in which the base is positioned and through which the base moves as the stylet assembly moves between its first and second positions, the width of said slide slots being greater than the diameter of said stop means pin whereby the third spring propels the slide forwardly past the pin with the forward end of the slide contacting the backside of the pedestal to push the cannula assembly from its first position to its second position, against the buffer force of the first spring, and further movement of the cannula assembly causing the outer end of the cannula to overcover the recess and capture the specimen therein.

18. The apparatus of claim 9 and further including means for adjusting the degree of exposure of the stylet means from the cannula as the apparatus is released from its cocked position.

19. The apparatus of claim 18 wherein said means includes the forward end of the sleeve being threaded and the adjusting means includes a spacer threadably received in the sleeve, said spacer adjusting the length of the sleeve and the extent of forward movement of the stylet relative to the cannula during operation of the apparatus.

20. The apparatus of claim 6 wherein said housing includes a pair of opposed longitudinal guide slots in the side thereof and the slide includes opposed fingers respectively extending outwardly from the side of the slide through said slots.

21. The invention of claim 1 and wherein said cocking means capable of moving said slide means to an approximate one-half cocked position.

22. The invention of claim 1 and further including for adjusting the degree of exposure of the stylet means from the cannula as the apparatus is released from its cocked position.

23. The invention of claim 22 and wherein said cocking means is capable of moving said slide means to an approximate fractional cocked position.

24. The invention of claim 22 and wherein said cocking means is capable of being preset to set the biopsy apparatus for obtaining a soft tissue specimen.

25. The invention of claim 1 wherein the cocking means includes a cylindrical sleeve slidingly installed over the housing for moving the slide means rearwardly in the housing against the force of the spring means.

26. The apparatus of claim 25 wherein said means includes the forward end of the sleeve being threaded and the adjusting means includes a spacer threadily received in the sleeve with respect to the sleeve, said spacer adjusting the length of the sleeve and the extent of forward movement of the stylet relative to the cannula during operation of the apparatus.