ULTRASONIC SURGICAL BLADE AND INSTRUMENT HAVING A GAIN STEP
An ultrasonic surgical blade, and an instrument, having a gain step. The blade body has, in any half wave length of the ultrasonic-surgical-blade body, a first vibration antinode, a vibration node, a second vibration antinode, and a gain step. The gain step is located between the second vibration antinode and the first vibration antinode. The gain step is spaced apart from the vibration node by a gain-step distance greater than 5% of the distance between the second vibration antinode and the first vibration antinode. The instrument includes the blade, a handpiece having an ultrasonic transducer, and an ultrasonic transmission rod whose proximal end is operatively connected to the ultrasonic transducer and whose distal end activates the blade. In one option, the first vibration antinode is the distal tip, and the gain step is located between the vibration node and the distal tip, resulting in an increased active length of the blade.
1 . An ultrasonic surgical blade comprising an ultrasonic-surgical-blade body having a longitudinal axis, having a distal tip which is a most-distal vibration antinode, having a most-distal vibration node, having a second-most-distal vibration antinode, and having a gain step, wherein the longitudinal axis consists essentially of a first geometric solid having a substantially constant first transverse cross-sectional area from the gain step to the distal tip and a second geometric solid having a substantially constant second transverse cross-sectional area from the gain step to the second-most-distal vibration antinode wherein at least one of the first and second transverse cross-sectional areas surrounds a void.
2 . The ultrasonic surgical blade of claim 1 , wherein the second transverse cross-sectional area is different than the first transverse cross-sectional area.
3 . The ultrasonic surgical blade of claim 1 , wherein the void includes a first longitudinal hole which is disposed in the first geometric solid and which extends proximally from the distal tip.
4 . The ultrasonic surgical blade of claim 3 , wherein the void includes a second longitudinal hole which is disposed in the second geometric solid and which is in fluid communication with the first longitudinal hole, and wherein the first and second longitudinal holes are adapted for irrigation and/or suction.
5 . The ultrasonic surgical blade of claim 3 , also including a membrane, which covers the first longitudinal hole, and which is removably or permanently attached to the first geometric solid at the distal tip.
6 . The ultrasonic surgical blade of claim 1 , wherein the first geometric solid has a first mass, extends from the gain step to the distal tip, and has a non-constant first transverse cross-sectional area, wherein the second geometric solid has a second mass, extends from the gain step to the second-most-distal vibration antinode, and has a non-constant second transverse cross-sectional area, and wherein the second mass is different than the first mass.
7 . The ultrasonic surgical blade of claim 6 , wherein the shape and size of the first external perimeter of the first transverse cross-sectional area is substantially equal to the shape and size of the second external perimeter of the second transverse cross-sectional area.
8 . The ultrasonic surgical blade of claim 7 , wherein at least one of the first and second transverse cross-sectional areas surrounds a void.
9 . The ultrasonic surgical blade of claim 8 , wherein the void includes a first longitudinal hole which is disposed in the first geometric solid and which extends proximally from the distal tip.
10 . The ultrasonic surgical blade of claim 9 , wherein the void includes a second longitudinal hole which is disposed in the second geometric solid and which is in fluid communication with the first longitudinal hole, and wherein the first and second longitudinal holes are adapted for irrigation and/or suction.
11 . The ultrasonic surgical blade of claim 9 , also including a membrane, which covers the first longitudinal hole, and which is removably or permanently attached to the first geometric solid at the distal tip.
12 . The ultrasonic surgical blade of claim 1 , wherein the ultrasonic-surgical-blade body has a longitudinal axis, has an active length, and is substantially asymmetric about the longitudinal axis along at least a portion of the active length.
13 . The ultrasonic surgical blade of claim 12 , wherein the ultrasonic-surgical-blade body is curved.