Abstract: Method, system and apparatus for carrying out a controlled heating of tissue in the region of skin dermis. A quasi-bipolar arrangement of wands or implants carrying multi-segmented active electrodes, temperature sensing and wand location LEDs as combined with a return electrode and heat sink function. Radiofrequency energization of the active electrodes is carried out in a ramping-up and pulsing fashion to provide relatively short therapy intervals. The combined return electrode and heat sink components may incorporate photo-detectors, which perform to insure proper alignment with the LED carrying active electrode sequences. An isotonic saline solution is located intermediate the contact surface of the combined return electrode and heat sink and the surface of skin over implanted active electrodes.

Abstract: Method for effecting a controlled heating of tissue within the region of dermis which employs heater implants which are configured with a thermally insulative generally flat support functioning as a thermal barrier. From the surface of this thermal barrier are supported one or more electrodes within a radiofrequency excitable circuit as well as an associated temperature sensing circuit. A model of R.F. current path flow is developed resulting in a current path index permitting a prediction of current path flow. Improved electrode excitation is developed with an intermittent R.F. excitation of electrodes shortening therapy time and improving skin protection against thermal trauma.

Abstract: Method, system and apparatus for carrying out accurate electrosurgical cutting. A thin resilient electrode is utilized at the forward end region of an instrument which is deployable from a longitudinally disposed slot positioned rearwardly of the tip of the instrument. Lateral sides of the slot extend between a forward location adjacent the tip and a rearward location. The electrode is deployed by urging it forwardly in compression to form an arch profile supported by the abutting slot sides adjacent the forward and rearward locations. Electrosurgically excitable with a cutting output, the electrode may carry out a cutting action both during its deployment and retraction into the noted slot. This permits a pivoting maneuver effective for circumscribing a volume of targeted tissue.

Abstract: Implant apparatus and method for effecting a controlled heating of tissue within the region of dermis of skin. The heater implants are configured with a thermally insulative generally flat support functioning as a thermal barrier. One surface of this thermal barrier carries one or more polymerically encapsulated heater resistor segments with a lead assemblage exhibiting a 4-point topology. Each of the encapsulated heater segments may be thermally associated with a metal thermal spreader dimensioned in correspondence with and aligned with the heater segments. The implants are located within heating channels at the interface between skin dermis and the next adjacent subcutaneous tissue layer such that the heat spreaders are contactable with the lower region of dermis. During therapy a conformal heat sink is positioned against the skin above the implants and a slight tamponade is applied through the heat sink to assure a proper form of conduction heat transfer.

Abstract: Method, system and apparatus for carrying out accurate electrosurgical cutting. A thin resilient electrode is utilized at the forward end region of an instrument which is deployable from a longitudinally disposed slot positioned rearwardly of the tip of the instrument. Lateral sides of the slot extend between a forward location adjacent the tip and a rearward location. The electrode is deployed by urging it forwardly in compression to form an arch profile supported by the abutting slot sides adjacent the forward and rearward locations. Electrosurgically excitable with a cutting output, the electrode may carry out a cutting action both during its deployment and retraction into the noted slot. This permits a pivoting maneuver effective for circumscribing a volume of targeted tissue.

Abstract: The capture component of tissue retrieval apparatus is strengthened to improve its structural integrity when utilized within very dense tissue. Eyelet structures carrying pursing cable are improved through the utilization of slightly expanded constant widths with diminished lengths to avoid fold back phenomena. The pursing cables employed with the capture component exhibit more than a 100% improvement in tensile strength at high electrosurgical cutting temperatures through the utilization of strands having about a 1.4 mil diameter formed with a type 316 stainless steel.

Abstract: Electrosurgical tissue specimen recovery apparatus and system employing a multi-leaf capture component configured with pursing cables which are electrosurgically excited to define a cutting leading edge. To complete a capture, the cables are loaded in tension to purse and thus converge the tips of the capture component leafs together. The forward regions of the leafs are configured with a combination of a thin flat stainless steel region over which a polymeric cable guide is positioned. The polymeric cable guide and stainless steel leaf driving combination improves frictional aspects as well as the resulting aspect ratio of a recovered tissue specimen.

Abstract: The capture component of tissue retrieval apparatus is strengthened to improve its structural integrity when utilized within very dense tissue. Eyelet structures carrying pursing cable are improved through the utilization of slightly expanded constant widths with diminished lengths to avoid fold back phenomena. The pursing cables employed with the capture component exhibit more than a 100% improvement in tensile strength at high electrosurgical cutting temperatures through the utilization of strands having about a 1.4 mil diameter formed with a type 316 stainless steel.

Abstract: An electrosurgical generator which provides a constant voltage and variable power output particularly suited for cutting arc formation at an active electrode which exhibits a dynamic active surface area of varying geometry. Essentially constant voltage-based control is achieved through the utilization of a d.c. link voltage the level of which functions to establish the amplitude of the output of an RF resonant inverter. A dual loop feedback control is described wherein output voltage based control signals are slowly introduced at low gain, while link voltage motor-based controls are comparatively rapidly applied. Enhanced development of a controlling d.c. link voltage is achieved through the utilization of an input network incorporating a power factor correction stage.

Abstract: Method, system and apparatus for carrying out accurate electrosurgical cutting. A thin resilient electrode is utilized at the forward end region of an instrument which is deployable from a longitudinally disposed slot positioned rearwardly of the tip of the instrument. Lateral sides of the slot extend between a forward location adjacent the tip and a rearward location. The electrode is deployed by urging it forwardly in compression to form an arch profile supported by the abutting slot sides adjacent the forward and rearward locations. Electrosurgically excitable with a cutting output, the electrode may carry out a cutting action both during its deployment and retraction into the noted slot. This permits a pivoting maneuver effective for circumscribing a volume of targeted tissue.

Abstract: Method, system and apparatus for carrying out accurate electrosurgical cutting. A thin resilient electrode is utilized at the forward end region of an instrument which is deployable from a longitudinally disposed slot positioned rearwardly of the tip of the instrument. Lateral sides of the slot extend between a forward location adjacent the tip and a rearward location. The electrode is deployed by urging it forwardly in compression to form an arch profile supported by the abutting slot sides adjacent the forward and rearward locations. Electrosurgically excitable with a cutting output, the electrode may carry out a cutting action both during its deployment and retraction into the noted slot. This permits a pivoting maneuver effective for circumscribing a volume of targeted tissue.

Abstract: System, method and apparatus for carrying out the recovery of an intact volume of tissue wherein a delivery cannula distal end is positioned in confronting adjacency with the volume of tissue to be recovered. A capture component formed of a plurality of metal leafs is deployed from the distal end of the delivery cannula. The tips of these leafs carry a pursing cable assembly which is electrically excited to electrosurgically cut around and circumscribe the tissue volume. These pursing cables are tensioned to complete the envelopment of the tissue volumes by drawing the leaf tips together. Drive to the capture component ultimately is developed from an electric motor and electrosurgical cutting current is supplied initially at a boost voltage level and thereafter at a lower normal cutting voltage level.

Abstract: System, method and apparatus for carrying out the recovery of an intact volume of tissue wherein a delivery cannula distal end is positioned in confronting adjacency with the volume of tissue to be recovered. A capture component formed of a plurality of metal leafs is deployed from the distal end of the delivery cannula. The tips of these leafs carry a pursing cable assembly which is electrically excited to electrosurgically cut around and circumscribe the tissue volume. These pursing cables are tensioned to complete the envelopment of the tissue volumes by drawing the leaf tips together. Drive to the capture component ultimately is developed from an electric motor and electrosurgical cutting current is supplied initially at a boost voltage level and thereafter at a lower normal cutting voltage level.

Abstract: A system and method for measuring total circulating blood volume and cardiac output employing an analyte diffusion approach. The analyte sensor as well as the analyte-containing fluid infusion procedure may be carried out with instruments which are inserted in the bloodstream at peripheral locations of the body spaced from the heart. A controller is provided to automatically carry out these measurements as well as to provide threshold comparisons for alerting the practitioner to excursion in the parameters. The preferred analyte containing fluid is an ammoniacal fluid and the preferred sensed components is ammonia gas.

Abstract: Apparatus system and method for cauterizing a volume of tissue wherein electrode assemblies are deployed from the forward end region of an instrument in conjunction with an electrosurgical cutting activity. Upon deployment to one or more deployed orientations, the electrodes assemblies are made biactive and the cauterization of tissue is carried out in a bipolar fashion. Following the procedure, the electrode assemblies are retracted toward the instrument and the instrument is withdrawn from the tissue region.

Abstract: System, method and apparatus for carrying out the recovery of an intact volume of tissue wherein a delivery cannula distal end is positioned in confronting adjacency with the volume of tissue to be recovered. An expandable metal capture component is expressed from the distal end of the cannula to expand while being electrically excited to electrosurgically cut around and circumscribe the tissue volume. Pursing cables are tensioned to complete the envelopment of the tissue volume, whereupon the volume is recovered by withdrawal of the instrument.

Abstract: Total ammoniacal concentration (TAC) in blood is measured and displayed on a repetitive basis by a controller driven sensor arrangement which may be utilized either with a catheter structure or with a bypass system. The catheter based sensors may be employed with a peripheral region of the vascular system of the body. Repetitive measurements are carried out and these measurements are subjected to a moving average filtering procedure, whereupon the filtered TAC values are displayed numerically and graphically. The controller functions to compute the rate-of-rise of TAC and compares that value with a threshold rate-of-rise valuation which is inputted by the practitioner. Threshold values for TAC also may be inputted and the system not only provides alarm warnings for threshold excursions in TAC above threshold or excursions in rate-of-rise of TAC above threshold but also provides a visual cuing as a warning that TAC is elevating from one filtered measurement to the next.