Aspiration control via flow or impedance

• US 20070005030A1
• Filed: 06/21/2005
• Published: 01/04/2007
• Est. Priority Date: 06/21/2005
• Status: Abandoned Application

• Current Assignee: Alcon Incorporated
• Original Assignee: Alcon Incorporated
• Inventors: Thomas, Roger, Nazarifar, Nader, Huculak, John, Hopkins, Mark, Todd, Kirk, Gao, Shawn
• Application Number:
  US11/158,259
• Publication Number:
  US 20070005030A1
• Time in Patent Office: Days
• US Class Current: 604/317
• CPC Class Codes: A61M 1/72 Cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 1/732 Visual indicating means for vacuum pressure
• CPC Class Codes: A61M 1/74 Suction control underwater drainage A61M1/61
• CPC Class Codes: A61M 1/743 by changing the cross-section of the line, e.g. flow regulating valves A61M1/7413 takes precedence
• CPC Class Codes: A61M 1/804 using Laval or Venturi jet pumps
• CPC Class Codes: A61M 2205/123 with incorporated reservoirs
• CPC Class Codes: A61M 2205/3379 Masses, volumes, levels of fluids in reservoirs, flow rates

Abstract

A microsurgical system capable of controlling aspiration and detecting an occlusion via monitoring a change in either suction flow rate or suction impedance.

Claims

1. Apparatus for controlling aspiration in a microsurgical system, comprising:

a pressurized gas source;

a vacuum generator fluidly coupled to said pressurized gas source;

an aspiration chamber fluidly coupled to said pressurized gas source and said vacuum generator;

a fluid level sensor operatively coupled to said aspiration chamber;

a pump fluidly coupled to said aspiration chamber;

a proportional controller; and

a computer electrically coupled to said fluid level sensor, said pump, and said proportional controller;

whereby upon selection of a desired suction flow rate for said aspiration chamber via said proportional controller, said fluid level sensor determines an actual fluid level in said aspiration chamber and provides a signal corresponding to said determined fluid level to said computer, and said computer calculates a suction flow rate in response to said determined fluid level and monitors a change in said suction flow rate to detect an occlusion.

2. The apparatus of claim 1 wherein said computer adjusts a surgical parameter of said apparatus in response to said occlusion.

3. The apparatus of claim 2 wherein said surgical parameter is selected from the group consisting of ultrasound energy, desired suction flow rate, desired suction pressure, infusion pressure, cut rate, and port open duty cycle.

4. The apparatus of claim 1 further comprising a surgical device for aspirating tissue fluidly coupled to said aspiration chamber, and wherein said computer adjusts a surgical parameter of said device in response to said occlusion.

5. The apparatus of claim 1 wherein said vacuum generator is a vacuum chip.

6. The apparatus of claim 1 wherein said vacuum generator is a venturi chip.

7. The apparatus of claim 1 wherein said pump is a peristaltic pump.

8. The apparatus of claim 1 wherein said microsurgical system is an ophthalmic microsurgical system.

9. A method of controlling aspiration in a microsurgical system, comprising the steps of:

creating a desired suction flow rate in an aspiration chamber using a pressurized gas source, a vacuum generator, and a pump;

aspirating fluid from a surgical device into said aspiration chamber;

determining an actual level of said fluid in said aspiration chamber;

calculating a suction flow rate in response to said actual level of fluid; and

monitoring a change in said suction flow rate to detect an occlusion.

10. The method of claim 9 further comprising the step of adjusting a surgical parameter of said apparatus in response to said monitoring step.

11. The method of claim 10 wherein said surgical parameter is selected from the group consisting of ultrasound energy, desired suction flow rate, desired suction pressure, infusion pressure, cut rate, and port open duty cycle.

12. The method of claim 9 further comprising the step of adjusting a surgical parameter of said device in response to said monitoring step.

13. Apparatus for controlling aspiration in a microsurgical system, comprising:

a pressurized gas source;

a vacuum generator fluidly coupled to said pressurized gas source;

an aspiration chamber fluidly coupled to said pressurized gas source and said vacuum generator;

a fluid level sensor operatively coupled to said aspiration chamber;

a pump fluidly coupled to said aspiration chamber;

a proportional controller; and

a computer electrically coupled to said fluid level sensor, said pump, and said proportional controller;

whereby upon selection of a desired suction flow rate for said aspiration chamber via said proportional controller, said fluid level sensor determines an actual fluid level in said aspiration chamber and provides a signal corresponding to said determined fluid level to said computer, and said computer;

calculates a suction flow rate in response to said determined fluid level;

calculates a suction impedance in response to said suction flow rate; and

monitors a change in said suction impedance to detect an occlusion.

14. The apparatus of claim 13 wherein said computer adjusts a surgical parameter of said apparatus in response to said occlusion.

15. The apparatus of claim 14 wherein said surgical parameter is selected from the group consisting of ultrasound energy, desired suction flow rate, desired suction pressure, infusion pressure, cut rate, and port open duty cycle.

16. The apparatus of claim 13 further comprising a surgical device for aspirating tissue fluidly coupled to said aspiration chamber, and wherein said computer adjusts a surgical parameter of said device in response to said occlusion.

17. The apparatus of claim 13 wherein said vacuum generator is a vacuum chip.

18. The apparatus of claim 13 wherein said vacuum generator is a venturi chip.

19. The apparatus of claim 13 wherein said pump is a peristaltic pump.

20. The apparatus of claim 13 wherein said microsurgical system is an ophthalmic microsurgical system.

21. The apparatus of claim 16 wherein said computer communicates a tissue property to a surgeon in response to said suction impedance.

22. A method of controlling aspiration in a microsurgical system, comprising the steps of:

creating a desired suction flow rate in an aspiration chamber using a pressurized gas source, a vacuum generator, and a pump;

aspirating fluid from a surgical device into said aspiration chamber;

determining an actual level of said fluid in said aspiration chamber;

calculating a suction flow rate in response to said actual level of fluid;

calculating a suction impedance in response to said suction flow rate; and

monitoring a change in said suction impedance to detect an occlusion.

23. The method of claim 22 further comprising the step of adjusting a surgical parameter of said apparatus in response to said monitoring step.

24. The method of claim 23 wherein said surgical parameter is selected from the group consisting of ultrasound energy, desired suction flow rate, desired suction pressure, infusion pressure, cut rate, and port open duty cycle.

25. The method of claim 22 further comprising the step of adjusting a surgical parameter of said device in response to said monitoring step.

26. The method of claim 22 further comprising the step of communicating a fluid property to a surgeon in response to said suction impedance.