Ultrasonic surgical tool
AssigneeSra Developments Limited
InventorsMichael John Radley Young, Stephen Michael Radley Young
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Abstract
At the surgical tool's proximal end, there is a first means (3) to generate ultrasonic vibration in a torsional shear mode. There is also a second means (2) to generate ultrasonic vibration in a longitudinal compression mode. A wave guide (4) is operatively connected to both generating means and extending therefrom by a distance of nλ/2 to a distal end provided with cutting and/or coagulating means. The ratio of the wavelengths of the longitudinal compression wave and the torsional shear wave, λc: λτ, is an odd number. Preferably λc=Nxλτ (where N is an odd integral number and x is an integer). Delicate shear motion of the torsional ultrasonic vibrational mode is combined with the more vigorous excitation of the longitudinal compression wave ultrasonic vibration.
Claims15
A surgical tool comprising at a proximal end, a first means to generate ultrasonic vibration in a torsional shear mode having a wavelength λT and a second means to generate ultrasonic vibration in a longitudinal compression mode having a wavelength λC, a wave guide operatively connected to said first and to said second generating means and extending therefrom by a distance of nλ/2, where n is an integer and λ is a wavelength for both λ=λC and λ=λT, to a distal end provided with cutting and/or coagulating means, wherein wavelengths of the longitudinal compression wave (λC) and the torsional shear wave (λT) propagating through the waveguide are different, and the ratio λC:λT of the wavelengths of the longitudinal compression wave (λC) and the torsional shear wave (λT), as the longitudinal compression wave and the torsional shear wave propagate through the wave guide, is an odd number.
Dependencies are inferred from the claim text.