Surgical instrument and method

• US 20030073902A1
• Filed: 10/11/2002
• Published: 04/17/2003
• Est. Priority Date: 10/12/2001
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Ams Research Corporation (Endo International PLC)
• Inventors: Neisz, Johann J., Bolea, Stephen L., Hauschild, Sidney F.
• Granted Patent: US 6,905,475 B2
• Time in Patent Office: Days
• US Class Current: 600/431
• CPC Class Codes: A61B 17/32037 for removing obstructions from inner organs or blood vessels, e.g. for atherectomy
• CPC Class Codes: A61B 17/3403 Needle locating or guiding means guides for suture needles A61B17/0482; guiding or tracking by nuclear magnetic resonance G01R33/285
• CPC Class Codes: A61B 17/3478 Endoscopic needles, e.g. for infusion biopsy needles A61B10/0233; catheters with injection needles A61M25/0067
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/22082 after introduction of a substance
• CPC Class Codes: A61B 2017/2946 Locking means
• CPC Class Codes: A61B 2018/00547 Prostate
• CPC Class Codes: A61B 2090/035 preventing further rotation
• CPC Class Codes: A61B 2090/0801 Prevention of accidental cutting or pricking
• CPC Class Codes: A61M 5/3007 with specially designed jet passages at the injector's distal end
• CPC Class Codes: A61M 5/3287 Accessories for bringing the needle into the body; Automatic needle insertion A61M5/20, A61M5/31525 take precedence
• CPC Class Codes: A61M 5/486 Indicating injection pressure
• CPC Class Codes: A61M 5/488 Limiting injection pressure

Abstract

Method and surgical instrument for treating prostate tissue including a surgical instrument having a main body, a needle deployment port, a needle, first and second handles and a lockout release mechanism to limit needle extension. Additionally, a kit includes the surgical instrument, together with a cystoscope, and optionally a syringe and reservoir of ethanol. The method includes needle-less injection and visualizing the ethanol injection by delivering both an echogenic agent and ethanol either by needle or needle-less injection or by providing an ultrasonically visible marker near the tip of the ethanol delivery cannula. The method also includes extending the needle transversely of the instrument housing using a link assembly.

Claims

1. An interlock release apparatus for a surgical instrument of the type having an remotely controllable extendable and retractable needle, the interlock release apparatus comprising a mechanism for selectively blocking and releasing first and second members from moving with respect to each other wherein the mechanism provides interference between the first and second members when in a blocking condition and the mechanism provides clearance between the first and second members when in a release condition.

2. The apparatus of claim 1 wherein the surgical instrument includes first and second manually graspable handles which extend the needle when the handles are moved towards each other, and which retract the needle when the handles are moved away from each other and the mechanism comprises a depressable button located on the first handle which prevents movement of the first handle towards the second handle in the blocking condition when the button is not depressed, and which permits movement of the first handle towards the second handle in the release condition when the button is depressed.

3. The apparatus of claim 2 wherein the button is resiliently biased towards the blocking condition such that the button returns to the blocking condition when the needle is fully retracted.

4. The apparatus of claim 3 wherein the first handle comprises a thumb ring carried by a slide and the second handle comprises a finger grip carried by a frame and the button is located on the slide and is adjacent an edge of the frame in the blocking condition.

5. The apparatus of claim 4 wherein the slide is free to advance the thumb ring towards the finger grip when the button is depressed to extend the needle to any one of a plurality of predetermined positions.

6. The apparatus of claim 1 wherein the surgical instrument further includes a syringe port for receiving a syringe for delivery of a fluid through the needle and still further includes first and second manually graspable handles which extend the needle when the handles are moved towards each other, and which retract the needle when the handles are moved away from each other and the mechanism comprises a lockout arm assembly having a first end located in the syringe port and engageable with the syringe, which prevents movement of the first handle towards the second handle in the blocking condition when the syringe is not received in the syringe port, and which permits movement of the first handle towards the second handle in the release condition when the syringe is received in the syringe port.

7. The apparatus of claim 6 wherein the lockout arm assembly further comprises a first lockout arm having the first end located in the syringe port, and a second lockout arm connected to the first lockout arm, with the second lockout arm having a distal end engageable with a blocking topology in one of the frame and slide preventing relative movement between the first and second handles in a blocking condition when the syringe is not present in the port and permitting relative movement between the handles in a release condition when the syringe is received in the port such that the needle is prevented from advancing in the absence of the syringe in the port in the blocking condition.

8. The apparatus of claim 7 wherein the lockout arm assembly further comprises a spring urging the lockout arm assembly to the blocking condition.

9. The apparatus of claim 7 wherein the blocking topology comprises a notch in a portion of the frame.

10. The apparatus of claim 1 wherein the mechanism comprises a positive locking ball detent with a manual access for release wherein a ball is resiliently urged out of the slide and towards the frame and rests in a recess in the frame preventing extension of the needle in a blocking condition and wherein the ball is manually displaced via a spherical recess to a release condition wherein the ball is out of positive locking with the frame and permits extension of the needle.

11. The apparatus of claim 1 wherein the mechanism comprises a stepped cam mounted on one of the first and second members and wherein a plurality of steps on the cam are engageable with the other of the first and second members to limit the distance the needle is able to be extended.

12. The apparatus of claim 11 wherein the stepped cam is mounted on a syringe port projection located on the first member and is rotatable thereabout to provide one of a plurality of steps for engagement with a portion of a finger support on the second member.

13. A method of injecting a drug into prostate tissue comprising

a. positioning a distal end of a surgical instrument adjacent a region of prostate tissue into which it is desired to inject the drug;

and

b. emitting a high pressure stream of the drug from a aperture in the distal end of the surgical instrument using needle-less injection.

14. The method of claim 13 wherein step a further includes positioning an injection head adjacent the prostate, and step b further includes injecting echogenic bubbles along with the drug.

15. The method of claim 14 wherein the injection head has a first inlet connected to a high pressure source of a liquid chemical agent and a second inlet connected to a gas delivery tube.

16. Apparatus for limiting a liquid pressure in a surgical instrument for delivering a liquid drug to a prostate, the apparatus comprising

a. a housing;

b. a pressure sensitive diaphragm contained within the housing and having one side responsive to a liquid pressure of in the surgical instrument and another side vented to atmosphere; and

c. a valve connected to the diaphragm with the valve positioned to selectively block delivery of the liquid when the liquid pressure exceeds a predetermined level.

17. The apparatus of claim 16 wherein the diaphragm is biased to a predetermined pressure by a spring.

18. The apparatus of claim 17 wherein the predetermined pressure is adjustable.

19. A pressure indicator for indicating when a predetermined pressure is exceeded in a surgical instrument for delivering a liquid drug to a prostate, the apparatus comprising:

a. a housing;

b. a passage in the housing for the liquid drug;

c. a piston responsive to pressure in the passage;

d. a spring acting between the piston and the housing; and

e. a visually perceptible indicator connected to the piston and extendable out of the housing when the pressure in the passage exceeds a predetermined level set by the spring such that the appearance of the indicator corresponds to a pressure in excess of the predetermined level.

20. The pressure indicator of claim 19 wherein the housing further comprises a cylinder receiving the piston and wherein the cylinder has a groove beginning at a starting point and extending a distance along the cylinder such that the liquid drug will leak past the piston via the groove when a predetermined maximum pressure level is reached within the passage causing the piston to move against the spring a distance sufficient to move the piston past the starting point of the groove.

21. A method of visualizing ethanol injection into a prostate comprising;

a. transurethrally inserting a surgical instrument to inject ethanol into a prostate; and

b. delivering both an echogenic agent and ethanol as the medium delivered to the prostate by the surgical instrument.

22. The method of claim 21 wherein step b further comprises switching between the echogenic agent and ethanol.

23. The method of claim 21 wherein step b further comprises simultaneously delivering the echogenic agent and the ethanol via a Y-connection.

24. A method of visualizing ethanol injection into a prostate comprising:

a. providing an ultrasonically visible marker near the tip of a delivery cannula for delivering ethanol to the prostate; and

b. observing the marker using ultrasound to position the cannula for delivery of ethanol to a desired location with respect to the prostate.

25. The method of claim 24 wherein step a comprises providing at least one roughened band at the distal end of the cannula.

26. The method of claim 24 wherein step a comprises providing a resistor located at the distal end of the cannula to provide a temperature signal indicative of the position of the distal end of the cannula.

27. The method of claim 24 wherein step a comprises providing a piezo oscillator to produce an ultrasonic beacon at the distal end of the cannula.

28. A method of extending a needle from a surgical instrument for injecting a liquid drug into a prostate, the method comprising:

a. providing a link assembly at a distal end of the surgical instrument with the link assembly connected to a needle and to a housing carrying the needle; and

b extending the needle generally transversely to the housing using a pusher moving longitudinally in the housing acting through the link assembly.

29. The method of claim 28 wherein step b further comprises pivoting the link assembly about a pivot connected to the housing.

30. The method of claim 28 wherein step b further comprises pivoting the needle using at least one link arm pivotally connected to the housing.

31. The method of claim 28 wherein step b further comprises moving the needle using a slot moving along a pin connected to the housing.

32. The method of claim 28 wherein step b further comprises guiding the needle through a slot in the housing.

33. A kit for injecting a liquid drug into a prostate, the kit comprising:

a. a cystoscope and scope sheath; and

b. a surgical instrument having a main body, a needle deployment port, a needle, first and second handles, and a lockout release mechanism to limit the distance the needle is extendable beyond the needle deployment port.

34. The kit of claim 33 further comprising:

c. a syringe for delivering the liquid drug to the prostate.

35. The kit of claim 34 further comprising:

d. a reservoir of ethanol; and

e. a syringe needle for drawing the ethanol from the reservoir into the syringe.

36. A method of visualizing placement of a therapeutically effective substance that is substantially invisible to ultrasound in the treatment of prostate tissue comprising adding an echogenic substance to the therapeutically effective substance to enable visualization during the procedure to assess penetration depth.

37. Apparatus for visualizing a polymer injection head which is formed of a clear polymer in the treatment of prostate tissue comprising a visually perceptible marker located on the head to indicate its position.

38. A selective coupling apparatus for a surgical instrument of the type having an remotely controllable extendable and retractable needle, the selective coupling apparatus comprising a mechanism for selectively engaging and releasing first and second members from moving with respect to each other wherein the mechanism provides a mechanical connection between the first and second members when in an operating condition and the mechanism provides clearance between the first and second members when in a de-coupled condition.