Phacoemulsification Needle Tip with Interior Step
A phacoemulsification needle is provided for use with a high-frequency phacoemulsification handpiece with the needle tip having a land formed on the interior of the tip proximate the tip opening, creating a “stepped” configuration.
1 . A phacoemulsification needle for emulsifying body tissue, said needle adapted to be attached to a phacoemulsification hand piece, said needle comprising:
a hollow needle shaft having a distal end and a proximal end,
said needle shaft having a longitudinally-extending central axis;
means formed at said proximal end to mount said needle to said handpiece;
a hollow needle tip formed at said distal end and communicating with said hollow needle shaft,
said tip having a side wall terminating at a lip,
said side wall and said lip defining a needle mouth,
said side wall having at least a first portion with at least a first thickness and a second portion with at least a second thickness,
said first side wall portion extending from said lip,
said first thickness being less than said second thickness,
said first and second side wall portions contiguous one to the other;
said emulsifying means comprising a land formed by said first and second side wall portions.
2 . The apparatus as recited in claim 1 wherein said lip is formed at right angles to said axis.
3 . The apparatus as recited in claim 1 wherein said lip is formed at a non-perpendicular angle to said axis.
4 . The apparatus as recited in claim 1 wherein said land is at a fixed distance from said lip.
5 . The apparatus as recited in claim 1 wherein said land is at a variable distance from said lip.
6 . The apparatus as recited in claim 1 wherein said land lies in a plane perpendicular to said axis.
7 . The apparatus as recited in claim 1 wherein said land lies in a plane non-perpendicular to said axis.
8 . A phacoemulsification needle for emulsifying body tissue, said needle adapted to be attached to a phacoemulsification hand piece, said needle comprising:
a hollow needle shaft having a distal end and a proximal end,
said needle shaft having a longitudinally-extending central axis;
means formed at said proximal end to mount said needle to said handpiece;
a hollow needle tip formed at said distal end and communicating with said hollow needle shaft,
said tip having a side wall terminating at a lip,
said side wall and said lip defining a needle mouth,
said side wall having a first portion with a first thickness and a second portion with a second thickness,
said first side wall portion extending from said lip to and coextensive with said second side wall portion,
said first thickness being less than said second thickness;
means formed on the interior of said tip for emulsifying said tissue,
said emulsifying means comprising a land formed by said first and second side wall portions.
9 . The apparatus as recited in claim 8 wherein said lip is formed at right angles to said axis.
10 . The apparatus as recited in claim 8 wherein said lip is formed at a non-perpendicular angle to said axis.
11 . The apparatus as recited in claim 8 wherein said land is at a fixed distance from said lip.
12 . The apparatus as recited in claim 8 wherein said land is at a variable distance from said lip.
13 . The apparatus as recited in claim 8 wherein said land lies in a plane perpendicular to said axis.
14 . The apparatus as recited in claim 8 wherein said land lies in a plane non-perpendicular to said axis.