Phacoaspiration flow restrictor with bypass tube
View Patent ↗A device for achieving high vacuum stability during phacoemulsification surgery includes a main aspiration line connected to a vacuum source which enables a fluid flow from a phacoemulsification handpiece tip to a drainage reservoir. A first tubing segment is provided in the main aspiration line along with a second tubing segment generally parallel to the first tubing section and a valve disposed in the second tubing segment regulates fluid flow through the second tubing segment in order to limit vacuum surge in the main aspiration line upon clearing of an occlusion in the phacoemulsification handpiece tip.
1. A device for achieving high vacuum stability during eye surgery, said device comprising:
a main aspiration line connected to a vacuum source and configured to enable a fluid flow from a surgical handpiece to a drainage reservoir;
a first tubing segment disposed in fluid communication with said main aspiration line, said first tubing segment having a lumen and a bore restriction inside a portion of said lumen of said first tubing segment, wherein said bore restriction has a cross sectional flow area less than a cross sectional flow area of said lumen when said first tubing segment is fully open and uncollapsed;
a second tubing segment disposed in fluid communication with said main aspiration line and substantially parallel to said first tubing segment, the said second tubing segment having a cross sectional flow area larger than said a-cross sectional flow area of the said bore restriction when said second tubing segment is fully open and uncollapsed; and
a valve, disposed adjacent to said second tubing segment, and configured to control fluid flow through the said first and second tubing segments by deforming said second tubing segment to limit vacuum surge in the said main aspiration line upon clearing of an occlusion in the surgical handpiece.
2. The device according to claim 1 further comprising a vacuum sensor disposed in the main aspiration line and effecting valve operation when a selected vacuum level is detected.
3. The device according to claim 2 wherein the valve comprises a pinch valve.
4. The device according to claim 3 wherein said second tubing segment includes a profile having a cross section including inside walls with subtending channels.
5. The device according to claim 4 , wherein said pinch valve is positioned to collapse said second tubing segment by forcing the inside walls toward one another.
6. The device according to claim 5 wherein a maximum valve caused collapse of said second tubing segment permits fluid flow through said subtending channels.
7. The device according to claim 1 wherein the first and second tubing segments are in fluid communication with said main aspiration line at spaced apart common junctions.
8. The device according to claim 7 wherein said valve is disposed between the spaced apart common junctions.
9. The device according to claim 8 further comprises a vacuum sensor disposed in said main aspiration line and effecting valve operation when a selected vacuum level is detected.
10. The device according to claim 9 wherein the valve comprises a pinch valve.
11. The device according to claim 10 said second tubing segment includes a profile having a cross section including inside walls with subtending channels.
12. The device according to claim 11 wherein said pinch valve is positioned to collapse said second tubing segment by forcing the inside walls toward one another.
13. The device according to claim 12 wherein a maximum valve caused collapse of said second tubing segment permits fluid flow through said subtending channels.
14. The device according to claim 1 , wherein the surgical handpiece is a phacoemulsification handpiece.
15. The device of claim 1 , further including a flow rate sensor.
16. The device of claim 1 , wherein the second tubing segment has a circular cross-section.
17. The device of claim 1 , wherein the valve operates to partially or fully collapse the second tubing segment.