A system for displaying characteristics of target tissue during an ablation procedure is provided that includes an electronic control unit (ECU) configured to receive data regarding electrical properties of the target tissue for a time period. The ECU is also configured to determine a value responsive to the data and indicative of at least one of a predicted depth of a lesion in the target tissue, a predicted temperature of the target tissue, and a likelihood of steam pop of the target tissue for the time period. The system further includes a display device operatively connected to the ECU. The display device is configured to receive the value and display a visual representation indicative of at least one of a predicted depth of a lesion in the target tissue, a predicted temperature of the target tissue, and a likelihood of steam pop of the target tissue for the time period.

A method of treating a patient with a therapeutic laser pulse includes applying a cooling mechanism to a first skin area, cooling a target skin area within the first the skin area from a first surface temperature to a second temperature through application of the cooling mechanism prior to application of the therapeutic laser pulse, initiating application of the therapeutic laser pulse at a first timepoint, while continuing to apply the cooling mechanism, determining a surface temperature of the target skin area a plurality of times during application of the therapeutic laser pulse at a refresh rate of 25 Hz to 400 Hz, and terminating the application of the therapeutic laser pulse at a second timepoint, based on the surface temperature determinations. Each of the plurality of surface temperature determinations occurs during a single therapeutic laser pulse duration from the first time point to the second timepoint.

A method for determining parameters for operating a light source within a photo-thermal targeted treatment system is disclosed. The method includes cooling a treatment location, administering first laser pulses at the treatment location, the first laser pulses having thermal energy below a known damage threshold, tracking skin surface temperatures at the treatment location while administering the first laser pulses, estimating a relationship between parameters for operating the light source and the skin surface temperature by fitting tracked skin surface temperature to a correlation model, determining a safe operating range for the light source to avoid thermal damage at the treatment location while still effectively targeting the chromophore, administering second laser pulses at the treatment location, the second laser pulses staying within the safe operating range for the light source, and adjusting the light source according to the tracked skin surface temperatures to stay within the safe operating range.

A magnetic resonance imaging (MRI) guided surgical system is provided that includes one or more surgical tools having components configured to develop reactive effects when exposed to MR signals generated by the MRI system. The system includes a control system that can determine whether the MR system is generating MR signals, and if the control system determines that the MR system is generating MR signals, mitigates the reactive effects of MR signals on components of the surgical tools. The system can include a cryoablation system with a cryoprobe having a probe shaft being made of a metallic material. If the control system determines that the MR system is generating MR signals, the control system can electrically disconnect the cryoprobe and/or ignore electrical signals generated by the electric heater in response to exposure to MR signals, and/or initiate a cooling operation of the probe shaft, whereby the cooling operation.

An electrosurgical waveform having both radiofrequency (RF) energy and microwave energy components that is arranged to perform efficient haemostasis in biological tissue. The waveform comprises a first portion primarily of RF electromagnetic energy, and a second portion primarily of microwave electromagnetic energy that follows the first portion. The second portion further comprises a plurality of RF pulses, wherein the first portion transitions to the second portion when either a duration of the first portion meets or exceeds a predetermined duration threshold, or an impedance determined during the first portion meets or exceeds a predetermined threshold. The waveform is arranged to deliver energy rapidly so that haemostasis can occur in a short time frame in a situation where the maximum available power is limited, or to avoid undesirable thermal damage to the biological tissue.

A method for controlling a waveform shape of a motional branch current in an ultrasonic transducer of a surgical device. The method may comprise generating a transducer drive signal by selectively recalling, using a direct digital synthesis (DDS) algorithm, drive signal waveform samples stored in a look-up table (LUT), generating samples of current and voltage of the transducer drive signal when the transducer drive signal is communicated to the surgical device, determining samples of the motional branch current based on the current and voltage samples, a static capacitance of the ultrasonic transducer and a frequency of the transducer drive signal, comparing each sample of the motional branch current to a respective target sample of a target waveform to determine an error amplitude, and modifying the drive signal waveform samples stored in the LUT such that an amplitude error between subsequent samples of the motional branch current and respective target samples is reduced.

A method for determining motional branch current in an ultrasonic transducer of an ultrasonic surgical device over multiple frequencies of a transducer drive signal. The method may comprise, at each of a plurality of frequencies of the transducer drive signal, oversampling a current and voltage of the transducer drive signal, receiving, by a processor, the current and voltage samples, and determining, by the processor, the motional branch current based on the current and voltage samples, a static capacitance of the ultrasonic transducer and the frequency of the transducer drive signal.

Systems and methods for estimating tissue parameters, including mass of tissue to be treated and a thermal resistance scale factor between the tissue and an electrode of an energy delivery device, are disclosed. The method includes sensing tissue temperatures, estimating a mass of the tissue and a thermal resistance scale factor between the tissue and an electrode, and controlling an electrosurgical generator based on the estimated mass and the estimated thermal resistance scale factor. The method may be performed iteratively and non-iteratively. The iterative method may employ a gradient descent algorithm that iteratively adds a derivative step to the estimates of the mass and thermal resistance scale factor until a condition is met. The non-iterative method includes selecting maximum and minimum temperature differences and estimating the mass and the thermal resistance scale factor based on a predetermined reduction point from the maximum temperature difference to the minimum temperature difference.

A magnetic resonance imaging (MRI) guided surgical system is provided that includes one or more surgical tools having components configured to develop reactive effects when exposed to MR signals generated by the MRI system. The system includes a control system that can determine whether the MR system is generating MR signals, and if the control system determines that the MR system is generating MR signals, mitigates the reactive effects of MR signals on components of the surgical tools. The system can include a cryoablation system with a cryoprobe having a probe shaft being made of a metallic material. If the control system determines that the MR system is generating MR signals, the control system can electrically disconnect the cryoprobe and/or ignore electrical signals generated by the electric heater in response to exposure to MR signals, and/or initiate a cooling operation of the probe shaft, whereby the cooling operation.

A method for determining parameters for operating a light source within a photo-thermal targeted treatment system for targeting a chromophore embedded in a medium includes: 1) administering a laser pulse at a preset power level below known pain and damage thresholds to a location to be treated; 2) measuring a skin surface temperature at the location; 3) correlation fitting a relationship between the light source parameters and the skin surface temperature at the location; 4) defining a safe operating range for the light source parameters to avoid pain and thermal damage at the location; 5) maintaining the skin surface temperature below the known pain and damage threshold and increasing the peak temperature and of the thermal gradient depth; and 6) administering a higher-level laser pulse to raise the temperature of the targeted chromophore to its required damage temperature.