Apparatus for and method of utilizing energy to excise pathological tissue
OwnerSamantha K. Daviinventor
Life of this patent
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Abstract
Pathological tissue is excised with a beam from a laser that is coupled through a flexible, optical waveguide to a collimator that reduces the beam cross-sectional area by variable, controlled amounts. A transparent bore or a graphite cannule couples the beam exiting the collimator to the tissue to vaporize same. An electrically responsive deflector gyrates the reduced cross-sectional area beam about a bore sight axis aligned with the cannula bore so that the excised tissue has a frusto-conical volume. To excise different, displaced tissue regions, a position servo system moves the cannula so the bore sight axis moves in a plane at right angles to a plane on the exterior surface containing the pathological tissue.
Claims41
An instrument for excising pathological tissue from an organ in a cavity of a living body comprising a source of coherent optical beam radiation having sufficient energy to vaporize the tissue, a cannula having a biocompatible exterior made of a material that can be inserted into the body cavity in contact with organs in the cavity without detrimental effects on the organs, said cannula having a longitudinal axis and an optically transparent interior extending along the axis, the transparent interior being bounded by an interior wall of the cannula, means for optically coupling the beam source to the cannula so energy from the beam is coupled to the tissue so the tissue is irradiated by the beam energy, the optical coupling means including an optical waveguide connected to be responsive to the beam, the waveguide being fabricated of a material that remains stable while transmitting the beam so that the beam mode is not perturbed as the beam propagates through the waveguide, the beam energy irradiating the tissue having sufficient energy to vaporize the irradiated tissue, the cannula being made of a material that substantially prevents heat transferred to the interior wall by radiation from the beam from being transferred to the exterior of the cannula so that organs in the body cavity contacting the cannula exterior are not substantially heated by radiation from the beam, means for selectively coupling the beam to the cannula, means for gyrating the beam irradiating the tissue about the longitudinal axis.
The instrument of claim 28 further including motor means for controlling the motion of the cannula while in the cavity to direct the cannula axis to different surface area portions of the tissue, and signal source means for deriving control signals for the motor means, the selective coupling means and the gyrating means to (1) maintain the cannula stationary in the cavity while the beam is irradiating the tissue, (2) prevent the beam from irradiating the tissue as the cannula is moved, and (3) gyrate the beam irradiating the tissue about the longitudinal axis of the cannula while the cannula is stationary in the cavity so a conical excision is provided in the tissue.
A method of excising pathological tissue from an organ in a body cavity without mechanically cutting a capsule in the cavity surrounding the organ comprising inserting a cannula through an opening in the body cavity and into proximity with a region of the capsule above a site from which the tissue is to be removed, then propagating a beam of coherent optical radiation through the cannula to burn a hole in the capsule, the hole having sufficient area to enable the cannula to be inserted through it, then inserting the cannula through the hole in the capsule and positioning the cannula so its longitudinal axis is aligned with the site, then maintaining the cannula stationary and irradiating the site with a beam of coherent optical radiation propagated through the cannula to remove the tissue.
An instrument for excising pathological tissue from an organ within a cavity of a living body comprising a laser for deriving a beam of coherent optical energy having sufficient energy to vaporize the tissue, an optical waveguide connected to be responsive to the beam, the waveguide being fabricated of a material that remains stable while transmitting the beam so that the beam mode is not perturbed as the beam propagates through the waveguide, a collimator positioned to be responsive to the beam exiting the waveguide for reducing the beam cross sectional area, and a cannula having a biocompatible exterior made of a material that can be inserted into the body cavity without detrimental effects on organs it contacts within the body cavity, said cannula being positioned to be responsive to the beam exiting the collimator, said cannula having a longitudinal bore sight axis and an optically transparent interior extending along the bore sight axis for coupling the reduced cross sectional beam to the tissue, the cannula transparent interior being bounded by an interior wall and being made of a material that substantially prevents heat transferred to the interior wall by radiation from the beam from being transferred to the exterior of the cannula so that organs in the body cavity contacting the cannula exterior are not substantially heated, an electric source for deriving a signal having a characteristic indicative of a desired deflection angle for the reduced cross sectional beam exiting the collimator, and an optical crystal deflector fixedly positioned with respect to the cannula for coupling the reduced cross sectional beam exiting the collimator to the cannula transparent interior and coupled to the source to be responsive to the characteristic for gyrating the reduced cross sectional area beam about the bore sight axis by an amount indicated by the characteristic.
A method of excising pathological tissue from an organ in a cavity of a living body comprising generating a beam of coherent optical beam radiation having sufficient energy to vaporize the tissue, selectively transmitting the beam through a cannula in the body so that the beam exiting the cannula irradiates and vaporizes the tissue, the cannula having a biocompatible exterior made of a material that can be inserted into the body cavity in contact with organs in the cavity without detrimental effects on the organs, said cannula having a longitudinal axis and an optically transparent interior extending along the axis, the transparent interior transmitting the beam exiting the cannula, the cannula being made of a material such that heating of the interior by radiation from the beam is not substantially transferred by conduction to the exterior of the cannula so that organs in the body cavity contacting the cannula exterior are not substantially heated, moving the cannula while it is in the cavity to enable different portions of the tissue to be irradiated and vaporized, preventing the beam from irradiating the tissue as the cannula is moved, and maintaining the cannula stationary in the cavity while the beam is irradiating the tissue, and gyrating the beam irradiating and vaporizing the tissue about the longitudinal axis of the cannula while the cannula is stationary in the cavity so a conical excision is provided in the tissue.
Dependencies are inferred from the claim text.