ULTRASONIC WAVEGUIDE AND BLADE
An ultrasonic clamp coagulator assembly that is configured to permit selective cutting, coagulation and clamping of tissue during surgical procedures. An elongated portion of the instrument can be configured for endoscopic applications and has an outside diameter of less than 6 mm. The construction includes a waveguide and blade that enable larger wave amplitude and a longer active blade length and still provide sufficient frequency margin or window. The waveguide is provided with a series of gain steps located at the distal portion of the waveguide preferably at the two most distal nodes in relation to the handpiece, or the two most proximal nodes in relation to the blade tip.
1 . An ultrasonic surgical waveguide having a proximal portion and a distal portion and the distal portion comprising an ultrasonic surgical blade body, the blade body having a distal tip, which is the most-distal vibration antinode; wherein the distal portion comprises a first gain step greater than unity and a second gain step greater than unity.
2 . The surgical waveguide of claim 1 , wherein the waveguide further comprises a first most-distal vibration node and one of the first or second gain step is positioned at the first most-distal vibration node.
3 . The surgical waveguide of claim 1 , wherein at least one of the first and second gain step is a gain feature selected from the group consisting of: a discrete change in outer diameter or perimeter, a taper, a longitudinal hole, a traverse hole, a void, a surface flat, a surface slot, and a change in material.
4 . The surgical waveguide of claim 1 , wherein at least one of the first and second gain step is a change of the waveguide from a first diameter to a second diameter.
5 . The surgical waveguide of claim 1 , wherein the waveguide further comprises a second most-distal vibration node and one of the first or second gain step is positioned at the second most-distal vibration node.
6 . The surgical waveguide of claim 1 , wherein the phase margin is greater than or equal to 50 Hz.
7 . The surgical waveguide of claim 1 , further comprising a first most-distal vibration node and a second most-distal vibration node and wherein the first gain step is positioned at the first most-distal vibration node and the second gain steps is positioned at the second most-distal vibration node.
8 . The surgical waveguide of claim 7 , wherein the phase margin is greater than 50 Hz.
9 . The surgical waveguide of claim 7 , wherein the phase margin is greater than 70 Hz.
10 . The surgical waveguide of claim 7 , wherein the phase margin is from about 50 Hz. to about 80 Hz.
11 . An ultrasonic surgical waveguide having a proximal portion and a distal portion and the distal portion comprising an ultrasonic surgical blade body, the blade body having a distal tip, which is the most-distal vibration antinode; wherein the distal portion, proximal to the blade body, comprises a first gain step greater than unity and a second gain step greater than unity.
12 . The surgical waveguide of claim 11 , wherein the phase margin is greater than or equal to 50 Hz.
13 . An ultrasonic surgical waveguide having a proximal portion and a distal portion and the distal portion comprising an ultrasonic surgical blade body, the blade body having a distal tip, which is the most-distal vibration antinode; wherein the distal portion comprises a first gain step greater than unity and a second gain step less than unity.
14 . The surgical waveguide of claim 13 , wherein the waveguide further comprises a first most-distal vibration node and one of the first or second gain step is positioned at the first most-distal vibration node.
15 . The surgical waveguide of claim 13 , wherein the at least one of the first and second gain step is a gain feature selected from the group consisting of: a discrete change in outer diameter or perimeter, a taper, a longitudinal hole, a traverse hole, a void, a surface flat, a surface slot, and a change in material.
16 . The surgical waveguide of claim 13 , wherein at least one of the first and second gain step is a change of the waveguide from a first diameter to a second diameter.
17 . The surgical waveguide of claim 13 , wherein the waveguide further comprises a second most-distal vibration node and one of the first or second gain step is positioned at the second most-distal vibration node.
18 . The surgical waveguide of claim 13 , wherein the waveguide further comprises a first most-distal vibration node and one of the first or second gain step is positioned at the first most-distal vibration node.
19 . An ultrasonic surgical waveguide having a proximal portion and a distal portion and the distal portion comprising an ultrasonic surgical blade body, the blade body having a distal tip, which is the most-distal vibration antinode; wherein the distal portion, proximal to the blade body, comprises a first gain step greater than unity and a second gain step less than unity.