An ultrasonic surgical instrument and method of limiting an ultrasonic blade temperature includes adjusting at least one power parameter of the ultrasonic energy in response to reaching a predetermined frequency parameter change threshold in the ultrasonic blade limiting the temperature of the ultrasonic blade to an upper temperature limit. The ultrasonic surgical instrument further includes an end effector having an ultrasonic blade, a jaw, and a controller. The jaw is movably positioned relative to the ultrasonic blade and configured to move between an open position and a closed position. The controller operatively connects to the ultrasonic blade and is configured to measure an ultrasonic frequency of the ultrasonic blade. The controller has a memory including a plurality of predetermined data correlations that correlate changes in measured ultrasonic frequency of the ultrasonic blade to a blade temperature of the ultrasonic blade.

A device for fragmenting a surgical implant includes a cap. The cap includes a first channel extending from a first end of the cap to the second end of the cap. The device includes a first electrode, a second electrode, and an endoscope coupled with the cap.

A method for treating a treatment site within a body of a patient with a catheter system includes generating energy with an energy source; positioning an inflatable balloon substantially adjacent to the treatment site, the inflatable balloon having a balloon wall that defines a balloon interior that receives a balloon fluid; receiving energy from the energy source with an energy guide; guiding the energy with the energy guide into the balloon interior; sensing acoustic sound waves generated in the balloon fluid with an acoustic sensor that is positioned outside of the body of the patient; generating a sensor signal with the acoustic sensor based at least in part on the sensed acoustic sound waves; electrically coupling a system controller to the acoustic sensor; receiving the sensor signal from the acoustic sensor with the system controller; and controlling operation of the catheter system with the system controller based at least in part on the sensor signal, the system controller being configured to recognize one of: (i) normal operation of the catheter system, and (ii) potential damage to the energy guide.

Retrieval of material from vessel lumens can be improved by electrically enhancing attachment of the material to the thrombectomy system. The system can include a catheter having a distal portion configured to be positioned adjacent to a thrombus in a blood vessel, an electrode disposed at the distal portion of the catheter, and an interventional element configured to be delivered through a lumen of the catheter. The electrode and the interventional element are each configured to be electrically coupled to an extracorporeal power supply.

An ultrasonic surgical instrument and method of sealing a tissue includes measuring a first measured termination parameter with a controller and terminating an ultrasonic energy and an RF energy when the first measured termination parameter reaches a set one of a first smaller tissue predetermined termination parameter or a first larger tissue predetermined termination parameter to thereby inhibit transecting the tissue. The ultrasonic surgical instrument further includes an end effector having an ultrasonic blade, an RF electrode, and a controller. The controller operatively connects to the ultrasonic blade and the RF electrode and is configured to terminate the ultrasonic energy and the RF energy when the first measured termination parameter reaches the set one of the first smaller tissue predetermined termination parameter or the first larger tissue predetermined termination parameter to thereby inhibit transecting the tissue.

An electrosurgical generator includes a first radio frequency source having a first power supply configured to output a first direct current waveform; a first radio frequency inverter coupled to the first power supply and configured to generate a first radio frequency waveform from the first direct current waveform; and a first controller configured to control the first radio frequency inverter. The electrosurgical generator also includes a second radio frequency source having: a second power supply configured to output a second direct current waveform; a second radio frequency inverter coupled to the second power supply and configured to generate a second radio frequency waveform simultaneously as the first radio frequency waveform; and a second controller configured to control the second radio frequency inverter.

A system includes a signal generator, configured to pass a generated signal, which has two different generated frequencies, through a circuit including an intrabody electrode. The system further includes a processor, configured to identify, while the generated signal is passed through the circuit, a derived frequency, which is derived from the generated frequencies, on the circuit, and to generate, in response to identifying the derived frequency, an output indicating a flaw in the electrode. Other embodiments are also described.

A system includes a signal generator, configured to pass a generated signal, which has two different generated frequencies, through a circuit including a bidirectional semiconductor device. The system further includes a processor, configured to identify, while the generated signal is passed through the circuit, a derived frequency, which derives from the generated frequencies, on the circuit, and to generate, in response to identifying the derived frequency, an output indicating that a property of the bidirectional semiconductor device is asymmetric. Other embodiments are also described.

A cordless surgical knife comprises an enclosure and a blade extending from the enclosure. The enclosure contains a differential amplifier circuit configured to provide an RF signal, an output monitor feedback circuit, a return monitor feedback circuit, and a microprocessor that receives data from the feedback circuits and adjusts the RF signal. The enclosure contains a receiving antenna that is operable to receive a wireless signal associated with the RF signal from tissue of a patient. A transmitting antenna may be in electrical contact with tissue of the patient and transmit the wireless signal. Optionally, both the receiving antenna and transmitting antenna include at least two separate inductive circuits aligned on different planes, or each of the receiving antenna and the transmitting antennas is encapsulated inside an enclosure floating in a liquid so that the antennas are aligned by gravity.

Retrieval of material from vessel lumens can be improved by electrically enhancing attachment of the material to the thrombectomy system. The system can include a catheter having a distal portion configured to be positioned adjacent to a thrombus in a blood vessel, an electrode disposed at the distal portion of the catheter, and an interventional element configured to be delivered through a lumen of the catheter. The electrode and the interventional element are each configured to be electrically coupled to an extracorporeal power supply.