An ablation system includes multiple electrodes configured to contact body tissue of a patient, including two or more ablation electrodes for contacting respective locations in a target organ and a return electrode. A signal-generating unit includes multiple signal generators, which are configured to apply respective composite signals to respective ones of the ablation electrodes. The composite signals include multiple, respective signal components, including respective ablation signals, having different, respective ablation-signal amplitudes and phases at a common ablation-signal frequency, and respective probe signals having respective probe-signal amplitudes and different respective probe-signal frequencies. A processor is coupled to measure the probe signals received by each of the multiple electrodes, and responsively to the measured probe signals, to control the ablation-signal amplitudes and phases.

A percutaneous catheter system for use within the human body and an ablation catheter for ablating a selected tissue region within the body of a subject. The percutaneous catheter system can include two catheters that are operatively coupled to one another by magnetic coupling through a tissue structure. The ablation catheter can include electrodes positioned within a central portion. The ablation catheter is positioned such that the central portion of a flexible shaft at least partially surrounds the selected tissue region. Each electrode of the ablation catheter can be activated independently to apply ablative energy to the selected tissue region. The ablation catheter can employ high impedance structures to change the current density at specific points. Methods of puncturing through a tissue structure using the percutaneous catheter system are disclosed. Also disclosed are methods for ablating a selected tissue region using the ablation catheter.

A dermal conditioning device for creating at feast one fissure, in a stratum corneum layer of an area of skirt, comprising: a non-invasive fissuring generator; a controller coupled to the non-invasive skin fissuring generator, a power supply coupled to the non-invasive skin fissuring generator and the controller; and a housing encasing the non-invasive skin fissuring generator and the controller, wherein the controller controls the non-invasive skin fissuring generator to: generate at least one signal, and apply the at least one signal to dehydrate the area of skin, and stress the external surface of the stratum corneum layer of the area of skin, the stress calibrated to produce a strain on the stratum corneum layer causing a formation of at least one fissure in the stratum corneum layer when the area of skin is dehydrated, while maintaining a pre-fissure immune status of the area of skin.

A method for determining a switch-off time of a medical instrument includes measuring the duration for which the temperature of a tissue is above 85° Celsius, preferably above 95° Celsius, calculating, preferably online, the mean temperature from the first time when 85° Celsius, preferably 95° Celsius is reached, measuring and/or calculating the energy input until 85° Celsius, preferably 95° Celsius, and preferably below 110° Celsius, preferably below 100° Celsius is reached, calculating a parameter SP, which links the above mentioned results, and switches off at a predetermined value. The method can be practiced with a medical instrument as well as an application and a storage medium.

A surgical instrument end effector assembly includes a first jaw member and a second jaw member. The second jaw member includes an ultrasonic blade body and first and second electrodes disposed on either side of the ultrasonic blade body and extending longitudinally along a majority of a length of the ultrasonic blade body. The ultrasonic blade body is adapted to receive ultrasonic energy from an ultrasonic waveguide. The first and second electrodes taper in width proximally to distally and are adapted to connect to a source of electrosurgical energy. The first jaw member is movable relative to the second jaw member between a spaced-apart position and an approximated position for grasping tissue therebetween.

A medical apparatus includes a probe, which includes an insertion tube configured for insertion into a body cavity of a patient, and a distal assembly, which is connected distally to the insertion tube and comprises a plurality of electrodes, which are configured to contact tissue within the body cavity. An electrical signal generator is configured to apply biphasic electrical pulses simultaneously to at least one group of two or more of the electrodes with energy sufficient to irreversibly electroporate the tissue contacted by the electrodes in the at least one group. A controller is coupled to measure time-varying voltage differences between the electrodes in the at least one group and to adjust the biphasic electrical pulses applied to the electrodes in the at least one group so that the voltage differences do not exceed a predetermined threshold at any time during application of the biphasic electrical pulses.

A system for delivering ultrasound energy to an internal anatomical target includes an ultrasound transducer having multiple transducer elements collectively operable as a phased array; multiple driver circuits, each being connected to at least one of the transducer elements; multiple phase circuits; a switch matrix selectably coupling the driver circuits to the phase circuits; and a controller configured for (i) receiving as input a target average intensity level and/or an energy level energy to be applied to the target and/or a temperature level in target, (ii) identifying multiple sets of the transducer elements, each of the sets corresponding to multiple transducer elements for shaping and/or focusing, as a phased array, ultrasound energy at the target across tissue intervening between the target and the ultrasound transducer, and (iii) sequentially operating the transducer-element sets to apply and maintain the target average energy level at the target. In various embodiments, the controller operates each of the transducer element sets in accordance with a pulse-width modulation pattern having a duty cycle selected to achieve the target average intensity level, energy level, and/or temperature level at the target in accordance with a time constant of the target tissue.

Apparatus and associated methods relate to controlling electrical power of an electrotherapeutic signal that is provided to a biological tissue engaged by an electrosurgical instrument during a medical procedure. Electrical power—a product of a voltage difference across and an electrical current conducted by the engaged biological tissue—is controlled according to a therapeutic schedule. The electrotherapeutic schedule can be reduced or terminated in response to a termination criterion being met. In some examples, the termination criterion is a current characteristic, such as, for example, a decrease in current conducted by the engaged biological tissue. In some examples, the termination criterion is a biological tissue resistance characteristic, such as, for example, an increase in the biological tissue resistance that exceeds a predetermined delta resistance value.

A sine wave generator includes a resonator circuit, a control circuit and a pulse generator. The resonator circuit is configured to receive energy pulses and to generate a resonator sinusoidal signal responsively to the energy pulses. The control circuit is configured to estimate a signal measure of the resonator sinusoidal signal, or of a signal derived from the resonator sinusoidal signal. The pulse generator is configured to generate the energy pulses responsive to the signal measure estimated by the control circuit, and to drive the resonator circuit with the energy pulses.

A method for operating an electrosurgical system including an ultrasound generator and an ultrasonic instrument, includes the steps: determining an initial resonant frequency of the ultrasonic instrument by the ultrasound generator, energizing the ultrasonic instrument by the ultrasound generator with an operating amplitude and an operating frequency which correspond to the initial resonant frequency, tracking the operating frequency of the ultrasound generator with changes in the resonant frequency of the ultrasonic instrument, and terminating the energizing of the ultrasonic instrument by the ultrasound generator. A method terminates the energizing of the ultrasonic instrument by the ultrasound generator, in a decay phase the operating amplitude of the ultrasound generator is reduced to zero with a predefined or predefinable rate of change. An ultrasound generator is also presented.