SYSTEMS AND METHODS FOR POWER AND FLOW RATE CONTROL

• US 20080125698A1
• Filed: 09/08/2006
• Published: 05/29/2008
• Est. Priority Date: 09/08/2006
• Status: Active Grant

• Current Assignee: Johnson & Johnson Surgical Vision, Inc. (Johnson & Johnson)
• Original Assignee: Advanced Medical Optics Incorporated (Johnson & Johnson)
• Inventors: Reisin, Carina, Gerg, James
• Granted Patent: US 8,652,086 B2
• Time in Patent Office: Days
• US Class Current: 604/35
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61F 9/00736 Instruments for removal of intra-ocular material or intra-ocular injection, e.g. cataract instruments A61F9/008 takes precedence
• 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 1/77 Suction-irrigation systems aspiration tips supplying fluids A61M1/85; specific for negative pressure wound therapy A61M1/92; combined with tracheal tubes A61M16/0463

Abstract

The invention is generally directed to systems and methods for fluid control, and more particularly to systems and methods for power and flow rate control for aspiration. In accordance with one embodiment, an aspiration system includes an aspiration line having distal and proximal ends and an aspiration port defined in the distal end; a fluid transport device operatively coupled to the proximal end of the aspiration line; and a flow restrictor operatively coupled to the aspiration line in between the fluid transport device and the aspiration port. To measure occlusion within the line, first and second pressure sensors are utilized, the first sensor being operatively coupled to the aspiration line between the port and the restrictor and the second sensor being operatively coupled to the aspiration line between the restrictor and the fluid transport device. The pressure differential between the two sensors can provide an indication of the onset, presence, and/or elimination of an occlusion.

Claims

1. An aspiration system comprising:

an aspiration line having distal and proximal ends and an aspiration port defined in the distal end;

a fluid transport device operatively coupled to the proximal end of the aspiration line;

a flow restrictor operatively coupled to the aspiration line in between the fluid transport device and the aspiration port;

a first vacuum sensor operatively coupled to the aspiration line between the port and the restrictor;

a second vacuum sensor operatively coupled to the aspiration line between the restrictor and the fluid transport device; and

a computer program product that includes a computer-usable medium having a sequence of instructions which, when executed by a processor, causes said processor to execute a process for measuring a pressure differential between the first and second vacuum sensors.

2. The system of claim 1, wherein the aspiration system is configured to be coupled to a phacoemulsification system.

3. The system of claim 1, wherein the fluid transport device is a vacuum-based pump.

4. The system of claim 1, wherein one of the first and second vacuum sensors includes an air transducer.

5. The system of claim 1, wherein the flow restrictor is a variable flow restrictor.

6. The system of claim 5, wherein the aspiration line includes a deformable segment operatively coupled to the variable flow restrictor, and the variable flow restrictor comprises:

a plunger element; and

an actuator coupled to the plunger element and configured to deform the deformable segment via the plunger element.

7. The system of claim 5, further comprising:

a computer program product that includes a computer-usable medium having a sequence of instructions which, when executed by a processor, causes said processor to control the variable flow restrictor.

8. The system of claim 1, further comprising a controller operatively coupled to the computer program product and configured to:

control a system parameter to be greater than or equal to the lower value or to be less than or equal to an upper value;

sense an occlusion in the aspiration line based on the pressure differential between the first and second vacuum sensors;

determine a duration of occlusion; and

control a system parameter based at least in part on at least one of (1) the sensing of an occlusion and (2) the duration of occlusion.

9. A surgical system for eye surgery comprising:

a handpiece configured to be placed in an operative relationship with an eye for a surgical procedure;

an irrigation fluid configured to supply an irrigation fluid source to the eye;

an aspiration line having an aspiration port coupled to the handpiece;

a vacuum-based aspiration source configured to apply a vacuum to the handpiece via the aspiration line in order to aspiration the irrigation fluid from the eye through the handpiece; and

an occlusion detecting system coupled to the aspiration line.

10. The surgical system of claim 9, wherein the occlusion detecting system includes:

a flow restrictor operatively coupled to the aspiration line in between the vacuum-based aspiration source and the aspiration port;

a first vacuum sensor operatively coupled to the aspiration line between the port and the restrictor;

a second vacuum sensor operatively coupled to the aspiration line between the restrictor and vacuum-based aspiration source; and

a computer program product that includes a computer-usable medium having a sequence of instructions which, when executed by a processor, causes said processor to execute a process for measuring a pressure differential between the first and second vacuum sensors.

11. The system of claim 10, further comprising a controller operatively coupled to the computer program product and configured to:

control a controlled system parameter to be greater than or equal to the lower value or to be less than or equal to an upper value;

sense an occlusion in the aspiration line based on the pressure differential between the first and second vacuum sensors;

determine a duration of occlusion; and

control a system parameter based at least in part on at least one of (1) the sensing of an occlusion and (2) the duration of occlusion.

12. The system of claim 11, wherein the controlled system parameter is at least one of supply irrigation pressure, supply irrigation rate, aspiration rate, aspiration vacuum level, and power applied to the handpiece.

13. The system of claim 11, wherein the flow restrictor is a variable flow restrictor and the controller is operatively coupled to the variable flow restrictor for controlling the aspiration rate.

14. The system of claim 9, wherein the handpiece is a phacoemulsification handpiece.

15. A method of operating a surgical handpiece, comprising:

placing a handpiece in an operative relationship with an eye for a surgical procedure;

supplying irrigation fluid from an irrigation fluid source to the eye;

applying vacuum from a vacuum-based fluid transport device to the handpiece in order to aspiration the irrigation fluid from the eye through the handpiece;

sensing a value of an occlusion-indicating parameter corresponding to an occlusion of the handpiece;

from the sensing of the value, determining a duration of occlusion; and

controlling a system parameter based at least in part on the duration of occlusion.

16. The method of claim 15, wherein the occlusion indicating parameter is at least one of supply irrigation pressure, supply irrigation rate, aspiration rate, aspiration vacuum level, and power applied to the handpiece.

17. The method of claim 15, further comprising using a flow restrictor between the vacuum-based fluid transport device and the handpiece.

18. The method of claim 17, wherein the occlusion indicating parameter is a pressure differential between the pressure between the flow restrictor and the handpiece and the pressure between the flow restrictor and the vacuum-based fluid transport device.

19. The method of claim 18, wherein the flow restrictor is a variable flow restrictor.

20. The method of claim 19, wherein the controlled system parameter is the aspiration rate controlled by the variable flow restrictor.

21. The method of claim 15, wherein the controlled system parameter is at least one of supply irrigation pressure, supply irrigation rate, aspiration rate, aspiration vacuum level, or power applied to the handpiece

22. The method of claim 15, wherein the controlled system parameter is controlled by at least one of lowering a maximum level and raising a minimum level of the controlled system parameter allowed during the surgical procedure.

23. The method of claim 15, further comprising an upper value of the controlled system parameter and a lower value of the controlled system parameter, wherein the controlled system parameter is controlled to be less than or equal to the lower value.

24. The method of claim 23, further comprising sensing a drop in the controlled system parameter below a lower threshold and, in response to the drop, controlling the controlled system parameter to be less than or equal to the upper value.

25. The method of claim 15, further comprising an upper value of the controlled system parameter and a lower value of the controlled system parameter, wherein the controlled system parameter is controlled to be greater than or equal to the upper value.

26. The method of claim 25, further comprising sensing a rise in the controlled system parameter above an upper threshold and, in response to the rise, controlling the controlled system parameter to be greater than or equal to the lower value.