SURGICAL DEVICE EMPLOYING A CANTILEVERED BEAM DISSECTOR

• US 20150257778A1
• Filed: 03/09/2015
• Published: 09/17/2015
• Est. Priority Date: 03/11/2014
• Status: Active Grant

• Current Assignee: Dr. Michael Rontal
• Original Assignee: Dr. Michael Rontal
• Inventors: Krapf, Charles W., Rontal, Michael, Harrington, Rick, Klock, Ryan
• Granted Patent: US 9,486,235 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/22012 in direct contact with, or very close to, the obstruction or concrement for removing obstructions in blood vessels by laser A61B18/245
• CPC Class Codes: A61B 17/2202 the ultrasound transducer being inside patient's body at the distal end of the catheter
• CPC Class Codes: A61B 17/24 for use in the oral cavity, larynx, bronchial passages or nose for medical inspection of cavities or tubes in the body A61B1/00; Tongue scrapers
• CPC Class Codes: A61B 17/320068 using mechanical vibrations, e.g. ultrasonic A61B17/22012 takes precedence; dental tooth drilling devices operated by vibration A61C3/03; removing intra-ocular material using mechanical vibrations A61F9/00745
• CPC Class Codes: A61B 2017/00734 battery operated
• CPC Class Codes: A61B 2017/32007 with suction or vacuum means
• CPC Class Codes: A61B 2017/320082 for incising tissue
• CPC Class Codes: A61B 2017/320098 with transverse or torsional motion

Abstract

A surgical instrument for treating body tissues through narrow body passages employs an elongated cantilevered beam having a proximal end supported in a rigid block and a narrower distal end extendable through the narrow passages. One or more piezoelectric actuators are fixed to the beam surface and energized from an AC source through electrodes interspersed with the piezoelectric actuators to produce oscillatory motion of the beam distal end in multiple modes of movement with sensing electronics to monitor and control the distal mechanical movement.

Claims

1. A system employing an elongated cantilevered beam having proximal and distal ends, with the distal end adapted to be inserted into a body passage so that it engages target tissues to produce therapeutic effects on the tissues, comprising:

piezoelectric material fixed to a surface of the beam between its proximal and distal ends;

an electrical excitation system connected to the piezoelectric material adapted to apply reciprocating currents to the material to produce deformations of the beam; and

a sensor for detecting the amplitude of deformation of the beam connected to said excitation system to determine the degree of engagement of the beam to modify the excitation of the fibers to control the engagement of the beam with the target tissues.

2. The system of claim 1 wherein the piezoelectric fibers are fixed to two opposed surfaces of the beam.

3. The system of claim 2 wherein the electrical excitation system for the piezoelectric fibers has an output;

and the system further comprises electrodes connected to the output of the electrical excitation system, said electrodes being interleaved with the piezoelectric fibers.

4. The system of claim 1 wherein the piezoelectric material is in the form of MFCs.

5. The system of claim 1 wherein the sensor for detecting the amplitude of deformation of the tip comprises fibers formed of a piezoelectric material.

6. The system of claim 5 wherein the sensor for detecting the amplitude of deformation of the tip has an output signal which is applied to a peak detector to generate a signal proportional to the resistance to motion of the tip in response to the degree of engagement of the tip with the target tissues to regulate the excitation system.

7. The system of claim 1 wherein the piezoelectric fibers are formed as macro fiber composites.

8. The system of claim 2 wherein said electric excitation system energizes the fibers on the two opposed surfaces of the beam in synchronism to produce reciprocating axial motion of the beam.

9. The system of claim 2 wherein said electrical excitation system energizes said fibers on the two opposed surfaces of the beam in a temporally offset manner to produce transverse wave and a whipping action at the beam tip.

10. The system of claim 2 wherein the electrical excitation system is connected to the piezoelectric fibers fixed to the two opposed surfaces of the beam by a switching circuit capable of connecting the fibers on both surfaces in synchronism to produce reciprocating axial motion of the beam or, alternatively, in a temporally offset manner so that as one side of the beam is extending the other side of the beam is contracting, causing motion of the beam tip in a direction normal to the two opposed surfaces of the beam.

11. The system of claim 10 further comprising an operator control connected to the switching circuit for connecting the excitation system to the fibers fixed to the two opposed beam surfaces either in synchronism or in a temporally offset manner.

12. The system of claim 1 wherein the modification of the excitation of the fibers controlled by the sensor for detecting the amplitude of deformation of the beam tip controls the frequency of the alternating current applied to the fibers.

13. The system of claim 10 wherein the switching circuit constitutes an H-bridge.

14. The switching system of claim 1 wherein the electrical excitation system comprises a microcomputer powered by a DC power supply.

15. The system of claim 14 wherein a microcomputer controls the frequency, amplitude and phase of the AC voltages applied to the MFCs according to a program for the microcomputer and sensor inputs.

16. The system of claim 14 which measures the primary transformer current to determine the distal tip loading and adjust the amplitude, frequency and phase relationship between two or more MFCs to optimize the surgery.

17. The system of claim 14, further comprising a user interface that comprises input and output devices for controlling the frequency, amplitude, phase, and duty cycle of the system.

18. The system of claim 1, wherein the beam is tubular and has longitudinally extending slots opening on the distal end of the beam spaced about the circumference of the beam.