Infusion sleeve with leakage control
An irrigation sleeve for a phacoemulsification needle has a collar to limit leakage of irrigating liquid in a direction forward of the sleeve when the sleeve is positioned on the needle. In one embodiment the sleeve and needle have mating grooves and ridges. In another embodiment an O-ring embedded in the sleeve forms a seal against the needle body.
1. An infusion sleeve for use with a phacoemulsification handpiece, said handpiece having a hollow phacoemulsification needle attached to and extending from a handpiece body, said needle having an outer surface, said handpiece having a pathway through which irrigating liquid passes, said infusion sleeve comprising:
a hollow tubular body with a length and a first, open end through which said needle is inserted,
said tubular body having an outer surface and an inner surface and a thickness between the outer surface and the inner surface;
a second end of the hollow tubular body having a tip,
said tip having an opening through which said needle protrudes;
said sleeve and said outer needle surface defining therebetween a passageway communicating with said liquid pathway to allow said liquid to pass into said sleeve when said sleeve is mounted to said handpiece;
at least one port formed on said sleeve to allow said liquid to exit said passageway; and
a locally thickened sleeve wall portion formed on said sleeve proximate said second sleeve end for preventing said liquid from discharging through said tip opening when said liquid flows through said sleeve,
said locally thickened sleeve wall portion having an inner surface portion, sized and shaped to be in contact with said needle outer surface along a sleeve seat that extends over a first lengthwise distance when said sleeve is positioned on said handpiece,
said first lengthwise distance substantially greater than the thickness of the tubular body at a location where the tubular body projects lengthwise away from the sleeve seat toward the first end of the hollow tubular body.
2. The infusion sleeve as recited in claim 1 further comprising
a circumferentially-extending groove formed in said needle outer surface; and
a circumferentially-extending rib formed on said inner surface of said sleeve,
said groove and said rib sized, shaped and dimensioned to interengage at a position proximate said second sleeve end.
3. The infusion sleeve as recited in claim 1 further comprising
a circumferentially-extending groove formed in said inner surface of said sleeve; and
a circumferentially-extending rib formed on said needle outer surface,
said groove and said rib sized, shaped and dimensioned to interengage at a position proximate said second sleeve end.
4. The infusion sleeve as recited in claim 1 wherein a circumferentially extending seal is interposed between the needle and tubular body at the locally thickened sleeve wall portion.
5. The infusion sleeve as recited in claim 4 wherein said seal is an O-ring.
6. The infusion sleeve as recited in claim 4 wherein the seal is embedded in the sleeve wall portion.