MEDICAL DEVICES AND METHODS INCORPORATING FRUSTRATED TOTAL INTERNAL REFLECTION FOR ENERGY-EFFICIENT SEALING AND CUTTING OF TISSUE USING LIGHT ENERGY

• US 20140066911A1
• Filed: 05/28/2013
• Published: 03/06/2014
• Est. Priority Date: 09/06/2012
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: NAU, WILLIAM H. Jr.
• Granted Patent: US 10,231,782 B2
• Time in Patent Office: Days
• US Class Current: 606/8
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 18/1445 at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod
• CPC Class Codes: A61B 18/1447 wherein sliding surfaces cause opening/closing of the end effectors
• CPC Class Codes: A61B 18/20 using laser
• CPC Class Codes: A61B 18/201 with beam delivery through a hollow tube, e.g. forming an articulated arm through a flexible conduit A61B18/22; Hand-pieces therefor
• CPC Class Codes: A61B 18/22 the beam being directed along or through a flexible conduit, e.g. an optical fibre; Couplings or hand-pieces therefor
• CPC Class Codes: A61B 2018/00202 rotating
• CPC Class Codes: A61B 2018/00601 Cutting
• CPC Class Codes: A61B 2018/0063 Sealing
• CPC Class Codes: A61B 2018/00648 using more than one sensed parameter
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/202 Laser enclosed in a hand-piece
• CPC Class Codes: A61B 2018/2272 with reflective or refractive surfaces for deflecting the beam A61B2018/2261, A61B2018/2266 take precedence

Abstract

A medical instrument includes two jaw members, at least one of which creates conditions of frustrated total internal reflection at a tissue-contacting surface when tissue is grasped between the two jaw members. The first jaw member may include an optical element having a tissue-contacting surface. The medical instrument also includes a light source that provides a light beam for sealing tissue. The light source is positioned so that the light beam is totally internally reflected from an interface between the tissue-contacting surface and air when tissue is not grasped by the jaw members. When tissue is grasped by the jaw members, at least a portion of the light beam is transmitted through that portion of the tissue-contacting surface that is in contact with the tissue. The light source may be movably coupled to a jaw member to scan the light beam and/or to change the incident angle based on optical properties of the tissue.

Claims

1. A medical instrument, comprising:

a first jaw member including a tissue-contacting surface;

a second jaw member movably coupled to the first jaw member, the first jaw member and the second jaw member cooperating to grasp tissue between the first jaw member and the second jaw member; and

a light source that provides a light beam for sealing tissue, the light source movably coupled to the first jaw member to adjust an incident angle with respect to the tissue-contacting surface of the first jaw member so that the light beam is internally reflected from the interface between the tissue-contacting surface of the first jaw member and air when tissue is not grasped between the first jaw member and the second jaw member, and at least a portion of the light beam is transmitted through that portion of the tissue-contacting surface of the first jaw member that is in contact with tissue when the tissue is grasped between the first jaw member and the second jaw member.

2. The medical instrument according to claim 1, wherein the light source is selected from the group consisting of an optical fiber, a light-emitting diode, a laser, a diode laser, and a fiber laser.

3. The medical instrument according to claim 1, wherein the second jaw member includes a light-absorbent element that absorbs light that is transmitted through the tissue.

4. The medical instrument according to claim 1, wherein the second jaw member includes a reflective material that reflects light that is transmitted through the tissue.

5. The medical instrument according to claim 1, further comprising an optical element disposed in the first jaw member, the optical element having a side that forms at least a portion of the tissue-contacting surface of the first jaw member.

6. The medical instrument according to claim 5, wherein the light source is rotatable to selectively provide a light beam having a variable angle of incidence with respect to an axis normal to the tissue-contacting surface of the optical element.

7. The medical instrument according to claim 6, wherein the light source is configured to rotate to an appropriate position based on at least one optical property of the tissue to be treated.

8. The medical instrument according to claim 7, wherein the at least one optical property of the tissue being treated is selected from the group consisting of index of refraction, absorption coefficient, scattering coefficient, and anisotropy coefficient.

9. The medical instrument according to claim 1, wherein the light source is configured to rotate with respect to the first jaw member.

10. The medical instrument according to claim 1, wherein the light source is configured to translate with respect to the first jaw member.

11. The medical instrument according to claim 10, wherein the light source is configured to scan the tissue with the light beam.

12. The medical instrument according to claim 1, wherein the light source is configured to move to an appropriate position based on at least one optical property of the tissue while the tissue is in contact with at least a portion of the tissue-contacting surface of the first jaw member.

13. A method of treating tissue with an optical energy-based medical instrument including a first jaw member and a second jaw member, the method comprising:

directing a light beam at an incident angle with respect to a tissue-contacting surface of the first jaw member so that the light beam totally reflects from the interface between the tissue-contacting surface of the first jaw member and air when tissue is not grasped between the first jaw member and the second jaw member, and so that at least a portion of the light beam transmits through the tissue-contacting surface of the first jaw member to tissue when tissue is grasped between the first jaw member and the second jaw member.

14. The method according to claim 13, further comprising:

determining at least one optical property of the tissue;

determining a desired incident angle with respect to the tissue-contacting surface of the first jaw member based upon the at least one optical property of the tissue; and

adjusting the light beam to the desired incident angle with respect to the tissue-contacting surface of the first jaw member.

15. The method according to claim 14, wherein the at least one optical property of the tissue is selected from the group consisting of index of refraction, absorption coefficient, scattering coefficient, and anisotropy coefficient.

16. The method according to claim 14, wherein adjusting the light beam to the desired incident angle includes adjusting the position of a light source that generates the light beam.

17. A optical-based tissue-sealing system, comprising:

a housing; and

an end effector assembly operably connected to the housing, the end effector assembly including;

a first jaw member including a tissue-contacting surface; and

a second jaw member movably coupled to the first jaw member, the first jaw member and the second jaw member cooperating to grasp tissue between the first jaw member and the second jaw member,

wherein the first jaw member includes a movable light source that provides a light beam for sealing tissue, the movable light source positioned with respect to the tissue-contacting surface so that the light beam is totally internally reflected from an interface between the tissue-contacting surface and air when tissue is not grasped between the first jaw member and the second jaw member, and at least a portion of the light beam is transmitted through the tissue-contacting surface to the tissue when tissue is grasped between the first jaw member and the second jaw member;

a sensor configured to sense at least one optical property of tissue grasped between the first jaw member and the second jaw member; and

a controller coupled to the movable light source and the sensor, the controller configured to change the position of the movable light source based upon the sensed at least one optical property of the tissue.

18. The optical-based tissue-sealing system according to claim 17, wherein the controller determines an incident angle at which to illuminate the tissue-contacting surface of the first jaw member with the light beam based upon the sensed at least one optical property of the tissue, and adjusts the position of the movable light source to illuminate the tissue-contacting surface of the first jaw member with the light beam at the determined incident angle.

19. The optical-based tissue-sealing system according to claim 17, wherein the at least one optical property of the tissue is selected from the group consisting of index of refraction, absorption coefficient, scattering coefficient, and anisotropy coefficient.