Modular device for robotic electrosurgery

Abstract

A robotic-assisted surgery system in which a device for providing electrosurgical functionality can be attached directly to or integrated within a robotic arm. The device can be a detachable module or capsule that can be moved between different robotic arms within the same environment. The device can include multiple modules, each providing a different treatment modality. Depending on the procedure to be performed, different modules or combinations of modules can be selected and attached to one or more robotic arms.

Description

[Technical field]

[0001] The present invention relates to an apparatus for robotic-assisted electrosurgery. In particular, the present invention relates to various modules that can be incorporated into a robotic surgical system and enable the system to operate with electrosurgical instruments. The modules may be removably attachable, for example, to allow the modules to be interchangeable between different robotic systems within the same operating room environment. The modules may be capable of being retrofitted into existing robotic surgical systems.

[0002] The modules may generate various types of electromagnetic energy for use in electrosurgical instruments, such as radio frequency and / or microwave energy for treating or measuring biological tissue, for example, radio frequency and / or microwave energy may be used to perform either ablation, hemostasis (i.e., sealing damaged blood vessels by promoting blood clotting), cutting, sterilization, etc. [Background technology]

[0003] Electromagnetic (EM) energy, particularly microwave and radio frequency (RF) energy, has the ability to cut, coagulate, and ablate body tissue and has proven useful in electrosurgery. Typically, devices for delivering EM energy to body tissue include a generator that includes a source of EM energy and an electrosurgical instrument connected to the generator for delivering energy to the tissue.

[0004] Tissue ablation using microwave EM energy is based on the fact that biological tissues are composed primarily of water. Human soft organ tissues typically have a water content of 70%-80%. Water molecules have a permanent electric dipole moment, meaning that there is an imbalance of charge throughout the molecule. This charge imbalance causes the molecules to move in response to forces generated by applying a time-varying electric field, as they rotate and their electric dipole moment aligns with the polarity of the applied electric field. At microwave frequencies, the rapid molecular vibrations cause frictional heating, resulting in the dissipation of field energy in the form of heat. This is known as dielectric heating.

[0005] This principle is utilized in microwave ablation therapy, in which the application of a localized electromagnetic field at microwave frequencies rapidly heats water molecules in targeted tissue, resulting in tissue coagulation and cell death. It is known to use microwave emitting probes to treat various conditions in the lungs and other organs. For example, in the lungs, microwave radiation can be used to treat asthma and to ablate tumors or lesions.

[0006] Surgical resection is a method of removing a portion of an organ from the human or animal body. Such organs may contain a large number of blood vessels. When tissue is cut (divided or transected), tiny blood vessels called arterioles are damaged or ruptured. Initial bleeding is followed by a clotting cascade in which blood is converted into a clot in an attempt to plug the bleeding point. During surgery, it is desirable for the patient to lose as little blood as possible, and therefore various devices have been developed in an attempt to provide a bleeding-free cut.

[0007] Instead of a sharp blade, it is known to use radio frequency (RF) energy to cut biological tissue. Cutting using RF energy works on the principle that as an electric current (aided by the ionic content of the cells and intercellular electrolytes) passes through the tissue matrix, heat is generated due to the impedance to the flow of electrons across the tissue. When an RF voltage is applied to the tissue matrix, sufficient heat is generated within the cells to evaporate the water content of the tissue. As a result of this increased desiccation, the tissue adjacent to the cutting pole of the RF blade loses direct contact with the blade, especially adjacent to the RF emission area of ​​the instrument (referred to herein as the RF blade) where the current density is highest in the entire current path through the tissue. The applied voltage is then present across almost the entire gap, resulting in the gap becoming ionized and forming a plasma with a volume resistivity that is very high compared to the tissue. This difference is important because it focuses the applied energy into the plasma that completes the electrical circuit between the cutting pole of the RF blade and the tissue. Any volatile material entering the plasma slowly enough will evaporate, hence the notion of a tissue-dissociating plasma.

[0008] The use of robotic devices to assist in surgery is rapidly increasing. Typically, robotic-assisted surgery involves the use of a robotic arm that can be directly or remotely controlled by a surgeon to perform various movements or manipulations of a given surgical procedure. The robotic arm may have an end effector at a distal end of the robotic arm. The end effector may be or carry a surgical instrument. Robotic-assisted surgery systems may be used in open and laparoscopic surgery.

[0009] It is known to use robotic-assisted surgical systems in electrosurgical procedures, for example the Da Vinch system manufactured by Intuitive Surgical, which allows the integration of a generator into a vision cart that can be connected to a patient cart carrying a robotic arm. Summary of the Invention [Means for solving the problem]

[0010] Most generally, the present invention provides a robotic-assisted surgery system in which an apparatus for providing electrosurgical capabilities is directly mountable to or integrated within a robotic arm. The apparatus may be a removable module (referred to herein as a "capsule") that may be movable between different robotic arms in the same environment. The apparatus may include multiple modules, each providing a different treatment modality. Depending on the procedure to be performed, different modules or combinations of modules may be selected and attached to one or more robotic arms.

[0011] The present invention may provide several advantages. First, by mounting the device directly on the robotic arm, the means for generating energy for electrosurgery may be closer to the electrosurgical instrument. This helps reduce or eliminate losses that may occur in transferring energy between the generator and the electrosurgical instrument. Second, by providing the device on the robotic arm, the need for separate operating room furniture to house the electrosurgical generator is avoided. This may save space in the operating room. Third, by providing a modular setup, it may be possible for each robotic arm of a multi-arm system to have the same functionality without the cost of separately configuring each arm for electrosurgery.

[0012] In a particularly advantageous configuration, the present invention may provide a robotic arm with a detachable electrosurgical module, which is powered by an internal power source of the robotic arm. For example, the robotic arm may have a DC power source available for control and movement of the end effector, as well as operation of the arm itself. The electrosurgical module may be configured to utilize the DC power source to generate other forms of energy, such as radio frequency or microwave energy, for example, that are supplied to an electrosurgical instrument held by the robotic arm. This configuration may be advantageous as it eliminates the need to provide a separate power source on the robotic arm.

[0013] According to one aspect of the invention, there is provided an electrosurgical generator unit for use in a robotic assisted surgical system, the electrosurgical generator unit including a housing configured to be removably attachable to an articulating robotic arm of the robotic assisted surgical system, a signal generator encased within the housing, the signal generator configured to generate an electrosurgical signal for use by the robotic assisted surgical system, and an energy delivery structure configured to couple the electrosurgical signal to the robotic assisted surgical system. This aspect of the invention provides a removable, and therefore replaceable, unit that provides a localized source of electrosurgical signals for use by a surgical instrument.

[0014] The electrosurgical generator unit may further include a controller encased within the housing and operably connected to the signal generator. The controller may be configured to receive a control signal and control the signal generator based on the received control signal. The control signal may preferably be transmitted through a robotic assisted surgery system. For example, the electrosurgical generator unit may further include an input portion communicatively connectable to a control network of the robotic assisted surgery system, the controller configured to receive the control signal from the control network of the robotic assisted surgery system. This configuration may avoid the need to provide a separate communication channel to the electrosurgical generator unit.

[0015] Alternatively or additionally, the controller may include a wireless communication module configured to wirelessly receive input control signals.

[0016] The signal generator may be configured to provide an electrosurgical signal for use in one or more of a number of treatment modalities. For example, the electrosurgical signal may be a microwave signal or a radio frequency (RF) signal having a power level suitable for causing tissue ablation at the distal end of the surgical instrument. In another example, the electrosurgical signal may be microwave energy or RF energy having a power selected to be suitable for measuring tissue properties without causing any tissue damage. The signal generator may be capable of generating both RF and microwave signals, either separately or simultaneously. As described in more detail below, the RF energy and / or microwave energy may be delivered in combination with a fluid (e.g., gas) to enable a plasma to impinge on the distal end of the surgical instrument.

[0017] Similarly, RF and / or microwave energy may be delivered in combination with a cryofluid to enable cryoablation to be performed at the distal end of the surgical instrument.

[0018] In other examples, the signal generator may include a pulse generator configured to generate an electrosurgical signal waveform that makes it suitable for causing electroporation of tissue at the distal end of the surgical instrument.

[0019] The signal generator may be configured to generate other types of energy, such as ultrasound.

[0020] The electrosurgical generator unit may itself have a modular configuration, with the housing being configured to accept one or more removable signal generator modules. In this configuration, the electrosurgical generator unit may be adjustably configured to generate electrosurgical signals for a desired purpose.

[0021] As mentioned above, the electrosurgical generator unit may further include a fluid supply and a fluid conduit configured to couple the fluid from the fluid supply to the robotic-assisted surgical system. In one example, the energy delivery structure for the electrosurgical signal and the fluid conduit may be encased in a common feed structure. The common feed structure may include a coaxial transmission line having an inner conductor separated from an outer conductor by a dielectric material, and the fluid conduit includes a passageway formed within the inner conductor.

[0022] In configurations in which the electrosurgical generator unit is configured to provide a measurement modality, the electrosurgical generator may further include a signal detector encased within the housing. The signal detector may be connected to the energy delivery structure and configured to sample a signal characteristic at the energy delivery structure. The signal characteristic may be, for example, the amplitude and / or phase of the reflected power at the energy delivery structure. The signal detector or controller within the housing may be configured to generate a detected signal indicative of the signal characteristic. The detected signal may be output, e.g., returned, through a control network of the robotic assisted surgical system for reading by a user, e.g., on a display of a control console.

[0023] The electrosurgical generator unit may include other types of measurements. For example, the electrosurgical generator unit may include a light source for performing laser spectroscopy and a sensor unit. The electrosurgical generator unit may further include any one or more of a temperature sensing module and a radiating tissue sensor.

[0024] In a particularly advantageous configuration, the electrosurgical generator unit may be powered via an internal power source of the robotic surgical system. Thus, the electrosurgical generator unit may include a power coupling unit configured to receive power from the robotic surgical system. The power supply may be a DC signal. The signal generator may be configured to generate the electrosurgical signal using the DC signal. The signal generator may be configured to regulate the voltage of the DC signal to a suitable level for use, for example, using a linear regulator or a switched mode regulator.

[0025] Additionally or alternatively, the electrosurgical generator unit may have an independent power source, for example, the electrosurgical generator unit may have a separate connection to a mains power source or the electrosurgical generator unit may include a battery encased within the housing.

[0026] In one example, the signal generator may include a microwave source and an amplification unit coupled to the microwave source. In this example, the electrosurgical signal may include a microwave signal. The amplification unit may include a power amplifier, and the signal generator may be configured to extract both a drain voltage and a source voltage for the power amplifier from the DC signal.

[0027] In another aspect, the present invention may provide an instrument holder for a robotic assisted surgical system. The instrument holder may include a body having a proximal end attachable to and operable by an articulating arm of the robotic assisted surgical system, a distal portion configured to hold a surgical instrument, and an intermediate portion configured to receive an electrosurgical generator unit, as described above. For example, the intermediate portion may include a recess into which the electrosurgical generator unit may be plugged. The instrument holder and the electrosurgical generator unit may have cooperating connectors to enable transfer of power and control signals therebetween. In particular, the instrument holder may be configured to couple an electrosurgical signal from the electrosurgical generator unit to a surgical instrument held in the distal portion.

[0028] In a further aspect, the present invention may provide a robotic assisted surgery system including an articulating arm, an instrument holder attached to a distal end of the articulating arm, an electrosurgical instrument attached to the instrument holder, and the electrosurgical generator unit described above removably attached to the instrument holder, wherein the instrument holder is configured to couple an electrosurgical signal generated by the electrosurgical generator unit to the electrosurgical instrument.

[0029] The electrosurgical instrument may include an elongated probe having a proximal energy transmission structure and a distal tip. The instrument holder may be configured to couple the electrosurgical signal to the energy transmission structure for delivery to the distal tip.

[0030] The robotic assisted surgery system may further include a control console connected to the articulating arm via a control network, the control console configured to control the electrosurgical generator unit using control signals transmitted via the control network.

[0031] As used herein, with respect to a coaxial transmission line or other coaxial structure, the term "inner" means radially closer to the center (e.g., axis) of the structure. The term "outer" means radially farther from the center (axis) of the structure.

[0032] The term "conductive" is used herein to mean electrically conductive, unless the context indicates otherwise.

[0033] As used herein, the terms "proximal" and "distal" refer to the location of the electrosurgical generator unit relative to the signal generator. In use, the proximal end is closer to the signal generator for providing the electrosurgical signal, while the distal end is further from the signal generator.

[0034] As used herein, "microwave" may be used broadly to refer to a frequency range of 400 MHz to 100 GHz, but preferably refers to a range of 1 GHz to 60 GHz. Preferred spot frequencies of microwave EM energy include 915 MHz, 2.45 GHz, 3.3 GHz, 5.8 GHz, 10 GHz, 14.5 GHz, and 24 GHz. 5.8 GHz may be preferred. Devices may deliver energy at more than one of these microwave frequencies.

[0035] The term "radio frequency" or "RF" may be used to indicate frequencies between 300 kHz and 400 MHz.

[0036] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. [Brief description of the drawings]

[0037] [Figure 1] 1 is an overall schematic system diagram of a robot-assisted electrosurgical system to which the present invention is applied. [Diagram 2] FIG. 1 is a perspective view of an articulated robotic arm for electrosurgery, one embodiment of the present invention; [Diagram 3] FIG. 1 is a schematic diagram of an instrument holder for an articulated robotic arm in accordance with one embodiment of the present invention. [Figure 4] FIG. 1 is a schematic diagram of a detachable electrosurgical capsule for a robotic arm according to one embodiment of the present invention. [Diagram 5] 5 is a schematic diagram of a microwave generating module suitable for use in the removable electrosurgical capsule of FIG. 4. [Figure 6] FIG. 5 is a schematic diagram of components for projecting DC power energy and low power microwave energy onto a common feed line suitable for use in the detachable electrosurgical capsule of FIG. 4. [Figure 7] FIG. 5 is a circuit diagram showing a microwave generating module suitable for use in the removable electrosurgical capsule of FIG. 4. [Figure 8] 5 is a schematic diagram of another microwave generating module suitable for use in the removable electrosurgical capsule of FIG. 4. [Figure 9] FIG. 1 is a schematic diagram of an electrosurgical instrument that can be accommodated by an articulating robotic arm in one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] The present invention relates to the creation and use of electrosurgical instruments in the context of robotic assisted surgery. Figure 1 is an overall schematic system diagram of a robotic assisted electrosurgical system 100 to which the present invention applies. The system 100 includes three main entities: a robotic surgical tool 102, a surgical table 104, and a control console 106.

[0039] The operating table 104 provides a location to receive a patient for a procedure that can be assisted by the robotic surgical tool 102.

[0040] In this example, the robotic surgical tool 102 includes a control column 108 having an articulating arm 110 extending therefrom. The control column 108 may support a number of articulating arms. An instrument holder 112 is attached to a distal end of the articulating arm 110. The instrument holder 112 is configured to hold a surgical tool 114. In this example, the surgical tool 114 is shown as a rigid elongated element suitable for insertion into a patient's body using, for example, known laparoscopic techniques. The articulating arm 110 allows the position and angle of the surgical tool 114 to be changed relative to the surgical table 104. The control column 108 may also be movable within the operating room environment.

[0041] The instrument holder 112 may include various ports that are connectable to the surgical instrument 114. For example, the instrument holder 112 may provide a link that can control an end effector of the surgical instrument 114. The instrument holder 112 may also be used to deliver power or other substances (e.g., saline, etc.) to the surgical instrument.

[0042] A control console 106, typically in the same room as the operating table 104 and robotic surgical tool 102, is typically separate from the robotic surgical tool 102 and is used to remotely control the articulating arm 110 and instrument holder 112. The articulating arm 110 can also be manually positioned.

[0043] In the present invention, the robotic surgical tool 102 includes a detachable electrosurgical capsule 116 configured to generate and deliver electrosurgical signals via the instrument holder 112 for use by the surgical instrument 114. In this example, the electrosurgical capsule 116 is secured to the articulating arm 110 by one or more suitable connections 120, such as, for example, straps. However, in other examples described herein, the electrosurgical capsule 116 may be directly connectable to the instrument holder 112, for example, as a plug-in module.

[0044] Electrosurgical capsule 116 may be a stand-alone unit for generating and delivering signals suitable for use in electrosurgery.

[0045] As described in more detail below, the electrosurgical capsule 116 may be powered by an internal DC power source of the robotic surgical tool 102. That is, the robotic surgical tool 102 may be connected to a main power source in a standard manner (not shown). The control column 108 may include circuitry for converting the main power source into a DC power source for use by the robot. The control column 108 may have a first DC power source for controlling the movement of the articulating arm 110. Typically, the first DC power source may have a voltage of 24V and allow a current of up to 2A. The control column 108 may provide a second DC power source for use by or with the instrument holder 112. The second DC power source may have the same voltage as the first DC power source (e.g., 24V) or a lower voltage (e.g., 12V). The second DC power source may have a more limited current source (e.g., 600mA or less). The electrosurgical capsule 116 may utilize either the first DC power source or the second DC power source. 1, electrosurgical capsule 116 is connected to control column 108 by a separate cable 118, which may be retained on articulating arm 110 by one or more clips 122. Cable 118 may carry a DC signal from a first DC power source. Alternatively or additionally, electrosurgical capsule 116 may be positioned to receive power via the same path as instrument holder 112.

[0046] 2 is a perspective view of an articulated robotic arm 111 for electrosurgery that is another embodiment of the present invention. Features in common with the system of FIG. 1 are given the same reference numerals. In this example, the articulated robotic arm 111 performs the same functions as the articulated robotic arm 110 of FIG. 1. However, instead of one or more electrosurgical capsules 116 being attached to its outer surface, the articulated robotic arm 111 has an instrument holder 112 with a recess configured to receive the electrosurgical capsule 116. The surgical capsule 116 may be removably mountable in the recess, for example, to allow it to be easily replaced for an electrosurgical capsule providing a different modality, or to allow the electrosurgical capsule 116 to be switched for another articulated robotic arm 111 on the same or a different control column.

[0047] Figure 3 is a schematic diagram of an instrument holder 112 for an articulated robotic arm 111 of the type shown in Figure 2. The instrument holder 112, in the example, has a generally cylindrical shape extending along a longitudinal axis aligned with a surgical instrument 114 extending from a distal portion 117 thereof, but may have any suitable shape.

[0048] The instrument holder 112 includes a proximal portion 113 attached to (and capable of pivoting on) a distal end of the articulating robotic arm. The proximal end 113 can be configured to receive a power input 124 that is transmitted through the articulating robotic arm.

[0049] In this example, the instrument holder 112 includes a middle portion 115 having a recess 126 formed therein. There may be multiple recesses formed around the circumference of the middle portion. The instrument holder 112 may thus be configured to receive one or more electrosurgical capsules within the recess 126. If multiple electrosurgical capsules 116 are attached, the instrument holder 112 may be configured to selectively connect any one or any combination of the electrosurgical capsules to the surgical instrument 114. The connection may operably connect the electrosurgical capsule to the distal instrument tip 136, for example, to enable electromagnetic signals (including, for example, radio frequency energy and / or microwave energy) to be transmitted to and delivered from the distal instrument tip 136. As described below, each electrosurgical capsule may be configured to generate an electromagnetic signal associated with a particular tissue treatment or measurement modality.

[0050] Generating the electromagnetic signal at the instrument holder 112 is advantageous because it reduces the path length the signal must travel before reaching the distal instrument tip 136. This configuration can therefore facilitate reducing power loss as the electromagnetic signal is transmitted. Thus, to achieve a given level of power at the distal instrument tip 136, the electrosurgical capsule may be required to generate less power than a more distant generator. Alternatively, it may mean that it may be possible to achieve a higher output at the distal instrument tip 136 for a given power source.

[0051] Additionally, having the electrosurgical generator on the instrument holder 112 eliminates the need for a separate floor-based generator unit that would otherwise take up space in the operating room.

[0052] The intermediate portion 115 may further include means for interconnecting the electrosurgical capsule. For example, the recess 126 may be fitted with one or more input / output ports on its interior surface. In the example shown in FIG. 3, there is an input port 130 configured to deliver power (e.g., a DC signal) to the electrosurgical capsule. The input port 130 is connected to the proximal portion 113 by a suitable transmission line 128 which in turn is connected to the power input 124. Similarly, there is an output port 132 configured to deliver an electromagnetic signal (e.g., radio frequency or microwave energy) from the electrosurgical capsule to the surgical instrument 114. The output port 132 may be connected to the distal portion 117 by a suitable transmission line 134 (e.g., a coaxial cable). The distal portion 117 may be configured with a suitable connector (e.g., a QMA connector, etc.) to connect the transmission line 134 to an energy transfer structure (e.g., another coaxial transmission line) within the surgical instrument 114 itself. This example is described below with reference to FIG. 9.

[0053] A surgical instrument 114 may be removably attached to the distal portion 117. The same instrument holder 112 may be used with multiple instruments in this manner. Additionally, the present invention provides that the instrument holder 112 may be used with multiple different types of electrosurgical capsules, allowing various combinations of instruments and energy modalities to be used interchangeably with the same instrument holder.

[0054] 4 is a schematic diagram of a removable electrosurgical capsule 116 for a robotic arm according to one embodiment of the present invention. The electrosurgical capsule 116 may be receivable within a recess 126 of the type described above. The electrosurgical capsule 116 includes a rigid housing 200 that may be shaped to cooperate with a recess in the instrument holder of the robotic arm to properly align the capsule. The electrosurgical capsule 116 includes an input portion 202 that is communicatively connectable to a control network of a robotic assisted surgery system, for example, via the instrument holder. The input portion 202 may also be configured to receive a power source (e.g., the instrument holder's internal DC power source), an operating portion 203 that houses various functional components or modules for generating and / or controlling electromagnetic signals, and an output portion 204 for delivering the electromagnetic signals to the instrument holder, from which the electromagnetic signals are transmitted to an electrosurgical instrument held by the robotic arm.

[0055] In this example, the input section 202 includes an input connector 206 for receiving input control and power signals. The output section 204 may include an output connector 208 for delivering the generated electromagnetic signals from the electrosurgical capsule 116.

[0056] In the following description, the operative portion 203 of the electrosurgical capsule 116 is presented as having a modular structure in which various functional elements may be removable or replaceable depending on the desired output electromagnetic signal. Such a structure is advantageous in terms of manufacturing flexibility. However, it can be understood that modularity of the capsule components is not required for the invention. The capsule may be "hardwired" to provide specific functions, in which case the modules described below may be combined or may include shared components.

[0057] In general, the electrosurgical capsules referred to herein are configured to generate electromagnetic (EM) radiation, such as radio frequency (RF) or microwave EM radiation, suitable for the treatment or measurement of biological tissue.

[0058] In one example, control of the capsule (or capsules) is performed using control signals delivered to a controller module 212 in the capsule via a control network of the robotic-assisted surgery system, such as, for example, using a control console. Control of the capsule may thus be centralized at a remote computing device 210, which may be a control console of the robotic-assisted system or a separate device. It may be preferable that control of the capsule is achieved via a wired connection. However, in some examples, the capsule may be configured to communicate wirelessly. The remote computing device 210 may be a wireless computing device, such as a laptop, a smartphone, and a tablet computer. The remote computing device 210 may wirelessly communicate with the electrosurgical capsule via a wireless communication channel to control its operation.

[0059] In some examples, different optional modules may be combined with the core module to provide the capsule with different electrosurgical capabilities.

[0060] Various electrosurgical modalities are presented below in the context of a robotic-assisted surgical system for use in laparoscopic or endoscopic procedures involving controlled delivery of EM energy, such as RF and microwave energy. Such EM energy may be useful in removing polyps and malignant tumors. However, it will be understood that the aspects of the invention presented herein need not be limited to this particular application. Also, aspects of the invention may be equally applicable to embodiments in which only RF energy is required, or only RF energy and fluid delivery are required.

[0061] Returning to Figure 4, the operational portion 203 of the electrosurgical capsule 116 in this example is configured as a modular system including a number of modules. The number of modules 202 includes a controller module 212, a signal generator module 214, and a power supply structure module 216. These may be the core modules of the operational portion 203. Additionally, the number of modules may include further optional modules, namely, a signal detector module 218, a fluid supply module 220, and one or more additional signal generator modules 222. The optional nature of these modules is indicated in Figure 4 by the dashed lines.

[0062] The controller module 212 has a wireless communication interface operable to wirelessly communicate with the remote computing device 210 to receive instructions or data therefrom. The controller module 212 is operable to provide a control command based on the received data. For example, in one embodiment, the control command may be all or a portion of the received data, and thus the controller module 212 may forward the received data as a control command. Forwarding may also involve removing a portion of the received data before forwarding. For example, the received data may include a data packet that includes both a control command and communication information, and the communication information is used to direct the data packet from its source (e.g., the remote computing device 210) to its destination (e.g., the controller module 212). The wireless communication channel 210 may be a direct channel between the remote computing device 210 and the controller module 212, but the wireless communication channel 210 may also be an indirect channel including one or more wired or wireless networks, such as, for example, the Internet, a local area network, and / or a wide area network. In either case, the controller module 212 may delete or strip this communication information (and, e.g., any other information) so that only the control command remains. However, additionally or alternatively, the controller module 212 may include a processor (e.g., a microprocessor) coupled to the wireless communication interface to receive the received data. In use, the processor may generate the control command based on the received data. That is, the received data may not include the control command or may include only a portion of the control command, such that the processor generates at least a portion of the control command itself. It will be understood that the control command is in a format that the module can understand and execute to perform one or more module functions.

[0063] The wireless communication interfaces of the controller module 212 and the remote computing device 210 allow the controller module 212 to communicate wirelessly with the remote computing device 210. Each wireless communication interface may be capable of communicating via one or more different protocols, such as 3G, 4G, 5G, GSM, WiFi, Bluetooth, and / or CDMA. In either case, the controller module 212 and the remote computing device 210 may communicate with each other via the same protocol, such as WiFi. Each wireless communication interface may include communications hardware for transmitting and receiving data signals, such as a transmitter and receiver (i.e., a transceiver). The communications hardware may also include an antenna, as well as an RF processor that provides RF signals to the antenna for transmitting and receiving data signals therefrom. Each wireless communication interface may also include a baseband processor that provides data signals to the processor and receives data signals from the processor. The exact structure of the wireless communication interfaces may vary between embodiments, as will be appreciated by those skilled in the art.

[0064] In one embodiment, the controller module 212 is operable to, for example, decrypt data received over the wireless communication interface from the remote computing device 210. The controller module 212 is also operable to, for example, encrypt data transmitted over the wireless communication interface to the remote computing device 210. For example, if the controller module 212 generates control commands, the controller module 212 may transmit those generated control commands to the remote computing device 210 over the wireless communication interface. If the controller module 212 includes a processor, the encryption and decryption processes may be performed by the processor. Alternatively, the controller module 212 may include a separate encryption device for performing the encryption and decryption. It will be appreciated that any encryption protocol may be used, as known by those skilled in the art. However, given the electrosurgical nature of the invention, a medical encryption protocol may be preferred. An advantage of requiring data to be transmitted to / from the controller module 212 in encrypted form is that malicious parties would find it more difficult or impossible to hack the electrosurgical system 200 to take control of the electrosurgical instrument 114. Thus, system security and patient safety are improved.

[0065] In one embodiment, the controller module 212 includes a watchdog (or fault detection unit) for monitoring a series of potential error conditions that would result in the system 200 not performing according to its intended specifications. The watchdog is operable to generate an alarm signal when one of the potential error conditions occurs. For example, the watchdog may monitor the status of communication between the wireless communication module and the remote computing device 210, and a potential error condition may be a loss of communication between the controller module 212 and the remote computing device 210 for a duration that exceeds a pre-set threshold or time period. For example, the watchdog may generate an alarm signal when the wireless communication module fails to communicate with the remote computing device 210 for more than 10 seconds. It will be understood that different periods will be used in different embodiments.

[0066] In one embodiment, the controller module 212 includes one or more sensors that monitor the operation of various parts of the system 200, and the watchdog may generate an alarm signal when the output of these sensors falls outside of preset limits. For example, the controller module 212 may include one or more temperature sensors operable to generate a temperature measurement based on the temperature of a part of the controller module 212, such as the processor or memory of the controller module 212. The watchdog may then be operable to generate an alarm signal based on a comparison of the temperature measurement to one or more preset temperature limits to indicate that the part is overheating. Additionally or alternatively, a different type of sensor (e.g., a voltage sensor or a current sensor) may be provided to monitor the operation of a fan that provides active cooling to the processor or memory, such that the watchdog generates an alarm signal if the sensor indicates that the fan has malfunctioned (e.g., it is not using voltage or current). Additionally or alternatively, a sensor may monitor the voltage level of a DC power supply of the controller module 212, and the watchdog may generate an alarm signal if the voltage level falls outside a predetermined acceptable range of operation. It will be appreciated that the controller module 212 may contain different types of sensors that monitor the operation of different elements of the controller module, and the watchdog may monitor the output of these sensors and generate an alarm signal if any one of these outputs falls outside of pre-set limits. In addition, the controller module 212 may contain sensors that monitor the operation of other modules, and the watchdog may monitor the output of these sensors and generate an alarm signal if any one of these outputs falls outside of pre-set limits.

[0067] The controller module 212 may respond to the alarm signal in a number of different ways. For example, the controller module 212 may have a watchdog send an alarm signal to the remote computing device 210 via a wireless communication interface. In this way, the remote computing device 210 may keep a record or log of when a fault occurs. The watchdog may also include in the alarm signal a reference to the type of fault the alarm signal relates to, so that the remote computing device 210 may include this information in the log. The remote computing device 210 may also externally control the capsule's response based on the alarm signal. For example, the remote computing device 210 may send specific control commands to the controller module 212 based on the alarm signal, for example, to stop the electrosurgical capsule 116 in a safe manner. In this way, the remote computing device 210 may externally control the electrosurgical capsule 116's response based on the alarm signal. Additionally or alternatively, the controller module 212 may itself generate control commands based on the alarm signal. In this way, the controller module 212 may internally control the electrosurgical capsule 116's response based on the alarm signal. This internal control mechanism may be particularly suitable for the loss of communication failures mentioned above, while the external control mechanism may be particularly suitable for the overheating failures mentioned above. Thus, a hybrid model may be adopted in which some failures are handled internally while some other failures are handled externally.

[0068] In one embodiment, if the controller module 212 includes a processor, the watchdog includes a separate processor (e.g., a microprocessor) so that the watchdog can ensure that the processor is functioning correctly, i.e., generate an alarm signal if the processor malfunctions (e.g., not using voltage or current). Alternatively, the watchdog can be implemented in software executed by the processor of the controller module 212, i.e., a separate hardware processor may not be included.

[0069] Thus, in summary, the controller module 212 receives data from the remote computing device 210 and provides control commands to the signal generator module 214 based on the received data.

[0070] The capsule 116 may be powered by a power supply from the robotic surgical system, for example received via an instrument holder. For example, the input connector 206 may include a power coupling unit configured to receive a power supply. The power supply may be a DC power supply from within the instrument holder, for example derived from a DC power supply used to operate the articulating arm.

[0071] The DC power source received at the input connector 206 may be used to power any one or more of the modules described herein. Alternatively or in addition, the capsule 115 may include a battery 213 encased within the housing 200. The battery 213 may provide a self-contained power source, for example, to supplement or provide a backup to the power supply received through the input connector 206.

[0072] The signal generator module 214 is in communication with the controller module 212 to receive control commands. For example, the signal generator module 214 may be coupled to the controller module 212 via a wired connection or cable. In use, the signal generator module 214 is operable to generate and control EM radiation based on the control commands to form an EM signal. The signal generator module may be any device capable of delivering EM energy for treatment of biological tissue.

[0073] For example, the signal generator module 214 may be an RF signal generator module capable of generating and controlling RF EM radiation, e.g., having a frequency of 100-500 KHz or 300-400 MHz. Further, the RF signal generator module may include a bipolar RF signal generator or a monopolar RF signal generator.

[0074] Alternatively or additionally, the signal generator module 214 may be a microwave signal generator module capable of generating and controlling microwave EM radiation having, for example, 433 MHz, 915 MHz, 2.45 GHz, 5.8 GHz, 14.5 GHz, 24 GHz, or 30-31 GHz.

[0075] Alternatively, the signal generator module 214 may be an electroporation signal generator module capable of generating and controlling EM radiation having a low frequency, for example, between 30-300 kHz.

[0076] The signal generator module 214 generates EM radiation based on the control command. Thus, an exemplary control command may include an instruction for the signal generator module 214 to turn on so as to generate EM radiation at its operating frequency, i.e., 433 MHz in the case of a 433 MHz microwave signal generator module. The control command may also include an instruction for the signal generator module 214 to turn off so as to stop generating EM radiation. Additionally or alternatively, the control command would include other commands that specify other parameters of the EM radiation, such as, for example, the duration for which the signal generator module should generate EM energy or the power (or amplitude) of the generated EM energy.

[0077] In one embodiment, the signal generator module 214 includes a pulse generator that is controllable by the controller module 212 based on a control command to generate pulsed EM radiation from the EM radiation. Thus, the signal generator module 214 may be an electroporation signal generator module. For example, the EM radiation generated and controlled by the signal generator module 214 is acted upon by the pulse generator to generate pulsed EM radiation that forms the EM signal received by the power feed structure module 216. In this manner, the signal generator module 214 is modified to provide a pulsed EM signal. The controller module 212 may control the pulse generator via a control command to simply turn "on" or "off" the signal generator module 214 to generate a pulsed or continuous EM signal, respectively. Alternatively, the control command may specify one or more pulse parameters, such as duty cycle, pulse width (e.g., 0.5 ns to 300 ns), rise time (e.g., picoseconds or nanoseconds), or amplitude (e.g., up to 10 kV). Additionally, the control commands may instruct the pulse generator to deliver a single pulse, a pulse train (e.g., number or duration of pulses), or a burst of pulses (e.g., burst duration, number of pulses in a burst, period between bursts).

[0078] In one embodiment, the signal generator module 214 includes one or more sensors that monitor the operation of different elements of the signal generator module 214 and send measurements to the controller module 212. As described above, the controller module 212 (via a watchdog) can then compare these measurements to tolerance limits and generate an alarm signal if any one of these different elements develops a fault. For example, the signal generator module 214 may include a temperature sensor operable to generate a temperature measurement based on the temperature of a portion of the signal generator module (e.g., an oscillator or an amplifier). The watchdog then generates the alarm signal based on a comparison of the temperature measurement to one or more pre-set temperature limits.

[0079] The signal generator module 214 may be powered by a signal received from the input connector 206 and / or by an internal battery 213. The signal may be a DC power source of the robotic arm to which the capsule is attached. The DC signal may be used to power an amplification unit to increase the power of the microwave signal as described below with reference to Figures 5-8. It is desirable for the power source of the electrosurgical capsule 116 to be either self-contained or to utilize power already available on the robotic arm. This configuration eliminates the need for a separate power supply.

[0080] In summary, the signal generator module 214 generates and controls the EM radiation based on the control commands that form the EM signal. The frequency of the EM radiation depends on the type of the signal generator. The feed structure module 216 receives the EM signal from the signal generator module 214.

[0081] The feeding structure module 216 communicates with the signal generator module 214 to receive the EM signal. The feeding structure module 216 provides an energy delivery structure configured to couple the EM signal to the surgical instrument via the robotic arm. The feeding structure module 216 includes a signal channel that conveys the EM signal from the signal generator module 214 to an output port of the feeding structure module 216. The output port is for outputting the EM signal to the output connector 208, and thus the output port may connect to a feeding structure in the surgical instrument 114 via a cooperating connector. The feeding structure module 216 may be coupled to the signal generator module 214 via a cable assembly that includes a signal channel. Also, the cable assembly may terminate at the output port. Thus, in one embodiment, the feeding structure module 216 may be a cable assembly that connects the signal generator module 214 to the output connector 208.

[0082] Optional modules 218, 220, and 222 will now be described in detail. The signal detector module 218 is configured to sample signal characteristics for the signal channel of the powering structure module 216 and generate a detection signal indicative of the signal characteristics. For example, the signal generator module 214 may be an RF signal generator module and the signal characteristic may be a voltage or current present on the signal channel. Alternatively, the signal generator 214 may be a microwave signal generator module and the signal characteristic may be a forward or reflected power present on the signal channel. In one embodiment, the signal generator module 214 may be configured to deliver a low-power EM signal for the purpose of signal detection, which may be referred to as a measurement signal because it is generated for the purpose of measuring biological tissue at the distal end of the surgical instrument 114. Alternatively, the additional signal generator module 222, described below, may be configured to provide the measurement signal. It will be appreciated that the signal detector module 218 measures the signal channel and thus measures both the signal emitted by the signal generator module 214 and the signal reflected back to the powering structure module 216 by biological tissue at the treatment site, for example, near the distal end of the surgical instrument. Thus, the measured signal characteristics are indicative of the biological tissue, and thus the detected signal varies with the tissue characteristics. In this manner, the detected signal may be used to determine tissue characteristics (e.g., tissue type).

[0083] In one embodiment, the controller module 212 is in communication with the signal detector module 218 to receive the detection signal. For example, the controller module 218 may be connected to the signal detector module 218 via a wired connection or cable. The controller module 212 is also operable to generate control commands to the signal generator module 212 based on the detection signal. It will be appreciated that the detection signal may be used (e.g., by the controller module 212 or the remote computing device 210) to determine characteristics of tissue at the treatment site, for example, the detection signal may indicate that the tissue is healthy or cancerous.

[0084] In use, the signal detector module 218 may provide a mechanism for the electrosurgical capsule 116 to dynamically respond to biological tissue being treated by the surgical instrument 114. For example, the signal generator module 214 may be a microwave signal generator module and the measured signal characteristics may include forward and reflected power sampled at a microwave signal channel of the feed structure module 216. Based on the forward and reflected power, the return loss measured at the signal channel may be between -6 dB and -10 dB. This return loss may be indicative of bleeding. The controller module 212 (or remote computing device 210) may determine this return loss and further determine that it is indicative of bleeding and may then generate control commands for the microwave signal generator module to deliver an EM signal at an appropriate (e.g., increased) power level and / or duty cycle until the bleeding stops. Cessation of bleeding may be indicated by a change in the return loss measured from the reflected power. In an alternative embodiment, the signal generator module 214 may be an RF signal generator module and the measured signal characteristics may include the voltage (or current) sampled on an RF signal channel of the feed structure module 216. An indication of the onset of bleeding may also be provided by a change in the measured voltage / current. Thus, the cutting action of any of the RF signal generator modules may be stopped, for example, to allow the bleeding to be addressed by a microwave signal generator module.

[0085] Additionally or alternatively, the controller module 212 is operable to transmit the detection signals from a wireless communication interface, for example, to the remote computing device 210. The remote computing device 210 is thus operable to generate control commands based on the detection signals and then transmit those control commands to the controller module 212 for execution. It may be advantageous to have the remote computing device 210 generate the control commands because the remote computing device 210 may have more processing power than the controller module 212. It may be advantageous to have the controller module 212 generate the control commands instead because it may be significantly faster to transfer data directly from the controller module 212 to the signal generator module 214 rather than through the remote computing device 210. In an embodiment, both options may be available, and the choice of whether to generate the control commands in the signal generator module 214 or the controller module 212 depends on the circumstances. In either case, the detection signals may be used by the remote computing device 210 and / or the controller module 212 to dynamically adjust system performance based on the biological tissue being treated. These adjustments may improve treatment and patient safety.

[0086] In one embodiment, the power supply structure module 216 further includes a tuner connected to the signal channel to control the energy delivered by the EM signal. The tuner includes an adjustable impedance element that is controllable by the controller module 212 based on the detected signal. In one embodiment, the controller module 212 is connected to the power supply structure module 216 (and the tuner) via a wired connection or cable.

[0087] The tuner may function to facilitate efficient transfer of EM radiation to tissue. For example, information from the signal channel may be used to determine adjustments to an adjustable impedance for the signal channel to provide dynamic power matching between the surgical instrument 114 and the tissue. This ensures efficient and controllable energy transfer between the electrosurgical capsule 116 and the biological tissue.

[0088] In one embodiment, the adjustable impedance element may be an adjustable reactance (e.g., a capacitance or an inductance). For example, the adjustable reactance may include a plurality of reactance elements, each having a fixed reactance and independently switchable in or out of connection with the signal channel according to a respective control command from the controller module 212. Alternatively, each reactance element may have a variable reactance that is independently controllable according to a respective control command from the controller module 212. Alternatively, the adjustable reactance may be provided by a variable capacitor and / or a variable inductor, and the controller module 212 includes a self-adjusting feedback loop arranged to generate a control command for setting the reactance of the variable capacitor or variable inductor. Such an embodiment may be particularly suitable when the signal generator module 214 is an RF signal generator module and the signal channel is an RF signal channel.

[0089] In another embodiment, the adjustable impedance element may be an impedance adjuster having an adjustable composite impedance that is controllable by the controller module 212. Such an embodiment may be particularly suitable when the signal generator module 214 is a microwave signal generator module and the signal channel is a microwave signal channel.

[0090] In one embodiment, the signal detector module 218 or the power supply structure module 216 includes one or more sensors that monitor the operation of the different elements of the respective module and transmit measurements to the controller module 212. As mentioned above, the controller module 212 (via a watchdog) can then compare these measurements to acceptable pre-set limits and generate an alarm signal if any one of these different elements develops a fault.

[0091] The additional signal generator module 222 is similar to the signal generator module 214 in the sense that the additional signal generator module 222 is operable to generate and control EM radiation based on control commands from the controller module 212 to form an EM signal. Furthermore, to function with the additional signal generator module 222, the feed structure module 216 has one or more additional signal channels for coupling one or more additional signal generator modules 222 to an output port of the feed structure module 216. These additional signal channels may be included in the same physical structure (e.g., cable) as the signal channels discussed above. In one embodiment, the feed structure 216 functions to combine the EM signal from the signal generator module 214 with the EM signals from each additional signal generator module 222 so that they are all output from the output port to the distal end of the surgical instrument 114.

[0092] As discussed above, it will be appreciated that the signal detector 218 may be configured to measure signal characteristics at each additional signal channel of the feed structure module 216. Also, as discussed above, the feed structure module 216 may include a tuner connected to each additional signal channel to control the energy delivered by the EM signal.

[0093] Any number of additional signal generator modules 222 may be provided. Further, each additional signal generator module 222 may generate EM radiation to the signal generator module 212 and each of the other additional signal generator modules 222 at a different frequency.

[0094] In one embodiment, the signal channel of the signal generator module 214 and the signal channel of each additional signal generator module 222 may include physically separate signal paths within the feed structure module 216. The feed structure module 216 may also include a signal combining circuit having one or more inputs, each connected to a different one of the physically separate signal paths. The signal combining circuit also has an output connected to a common signal path to convey all the EM signals separately or simultaneously to an output port along a single channel. Stated differently, the signal combining circuit may provide a junction where multiple EM signals arrive from multiple different signal generator modules via separate signal paths, and all EM signals emanate via the same signal path for delivery to the electrosurgical instrument 204.

[0095] In one embodiment, the signal combining circuitry includes a switching device for selecting one or more of the EM signals to be connected to the common signal path. The switching device may be controllable based on a control command received from the controller module 212, for example, via a wired link between the controller module 212 and the power supply structure module 216.

[0096] The provision of additional signal generator modules 222a-n in combination with the above-mentioned modifications to the power supply structure module 216 means that the electrosurgical capsule 116 can be adapted to provide different types of EM radiation to treat biological tissue. An advantage of this modular nature is that the functionality of the electrosurgical capsule 116 can be increased so that the system can treat tissue in different ways to treat different conditions. Also, the functionality of the electrosurgical capsule 116 can be reduced so that the system is cheaper or smaller (e.g., more portable).

[0097] In one embodiment, each additional signal generator module 222 includes one or more sensors that monitor the operation of different elements of the additional signal generator module 222 and send measurements to the controller module 212. As described above, the controller module 212 (via a watchdog) can then compare these measurements to acceptable pre-set limits and generate an alarm signal if any one of these different elements develops a fault.

[0098] The fluid supply module 220 includes a fluid supply structure 228 in fluid communication with the fluid port for outputting fluid to the surgical instrument 114. In this example, the fluid supply structure 228 delivers the fluid to the output connector 208 where the fluid can be transferred to the surgical instrument via an appropriate coupling in the instrument holder 112. The energy delivery structure and the fluid supply can be combined in a common supply structure. For example, the transmission line 134 in the instrument holder 112 can be configured as a combined fluid and energy supply for delivering both fluid and EM energy to the surgical instrument 114. The surgical instrument 114 can then include a fluid supply that transports the fluid to the distal instrument tip 136.

[0099] A fluid supply 224 (eg, a pressurized gas canister, etc.) may be mounted to the exterior of the electrosurgical capsule 116. The fluid supply module 220 may be connected to the fluid supply 224 by a supply conduit 226.

[0100] The fluid supply module 220 is controllable by the controller module 212 based on control commands to supply and control the flow of fluid (e.g., gas or liquid) to the output connector 208 via the fluid supply structure 228. For example, the fluid supply module 220 may be connected to the controller module 212 by a wired connection or cable. The purpose of the fluid supply module 220 may be to provide a fluid to the distal instrument tip 136. For example, the fluid may be a gas provided to the surgical instrument 114 for generating plasma for the treatment of biological tissue. For example, non-thermal plasma may be used to sterilize tissue, such as to kill bacteria present inside a natural orifice or resulting from the insertion of a foreign body, i.e., metal, introduced into the body. Thermal plasma may also be used to cut tissue or perform surface coagulation, for example, for the treatment of ulcers on the surface of the tissue. The surgical instrument 114 may receive gas (from the fluid supply module 220) with either or both RF or microwave energy (from the signal generator module 212 and one or more additional signal generator modules 222) and may use these components to emit either thermal or non-thermal plasma. For example, in the case of non-thermal plasma, the signal generator module 212 (acting as an RF signal generator module) may generate a high voltage RF pulse (e.g., 400V peak for 1 ms) to initiate a plasma using the gas, followed by the additional signal generator module (acting as a microwave signal generator module) generating a microwave pulse with a 10% duty cycle and an amplitude of 30 W for a duration of 10 ms. On the other hand, in the case of thermal plasma, the duty cycle may be increased to 60% and the amplitude may be increased to 60 W. In a general sense, when there is a flow of gas, the RF EM radiation may be controlled to impinge on the conducting gas plasma, and the microwave EM radiation may be arranged to sustain the gas plasma. In one embodiment, the distal instrument tip 136 includes a bipolar probe that impinges on the conductive gas between its two conductors.As will be known to those skilled in the art, for example in view of WO2012 / 076844, which is incorporated herein by reference, the ability to deliver a combination of microwave energy and RF energy allows for a high level of control over the thermal or non-thermal plasma generated at the distal instrument tip 136.

[0101] In one embodiment, the fluid supply module 220 may provide liquid (e.g., saline) to the distal instrument tip 136. In one embodiment, injection of fluid (such as saline) is used to distend biological tissue at the treatment site. This may be particularly useful when the instrument is used to treat the walls of the intestine or esophagus, or to protect the portal vein or pancreatic duct when a tumor or other abnormality is located in close proximity, protecting these structures and creating a cushion of fluid. Distending tissue in this manner may help reduce the risk of intestinal perforation, damage to the wall of the esophagus or leakage from the pancreatic duct, or damage to the portal vein, etc. This aspect may allow other conditions to be treated when the abnormality (tumor, growth, lump, etc.) is close to a sensitive biological structure.

[0102] The fluid supply module 220 may also be configured to receive fluid from the surgical instrument 114. For example, fluid present at the treatment site at the distal instrument tip 136 may be aspirated through the instrument fluid supply to the fluid supply module 220, e.g., by a pump or other suction device in fluid communication with the fluid supply structure.

[0103] In one embodiment, the fluid supply module 220 includes a temperature control element controllable by the controller module 212 based on a control command to change the temperature of the fluid flow within the fluid supply structure. In this manner, the fluid may be heated or cooled before being delivered to the distal instrument tip 136. The temperature control element may provide only heating or only cooling. The temperature control element may include a heating device for heating the fluid. Also, the temperature control element may include a cooling device for cooling the fluid.

[0104] In one embodiment, the signal generator module 212 (or the additional signal generator module 222) and the fluid supply module 220 can be used together to provide a cryoablation function. For example, the signal generator module 212 can be a microwave signal generator module, and the fluid supply module 220 can be configured to supply a tissue freezing fluid to the surgical instrument 114. Thus, the electrosurgical capsule 116 can freeze biological tissue in the region around the distal instrument tip 136 and apply microwave energy to the frozen tissue. Because water molecules in frozen tissue have reduced vibrational and rotational degrees of freedom compared to unfrozen tissue, less energy is lost to dielectric heating when microwave energy is transmitted through the frozen tissue. Thus, by freezing the region around the distal end portion, microwave energy emitted from the distal end portion can be transmitted through the frozen region with low loss to the tissue surrounding the frozen region. This allows for an increase in the size of the treatment site without the need to increase the amount of microwave energy delivered to the distal end portion as compared to conventional microwave ablation instruments (e.g., probes). Once the tissue surrounding the frozen region has been ablated by the microwave energy, the frozen region can be allowed to gradually thaw so that the region dissipates the microwave energy and is ablated. The device of the present invention also allows various combinations of microwave energy and tissue freezing to be used to efficiently ablate biological tissue.

[0105] The tissue freezing fluid may be a cryogenic liquid or gas and may be referred to herein as a cryogen. The term "cryogene" may refer to a substance used to produce temperatures below 0°C. Suitable cryogens include, but are not limited to, liquid nitrogen, liquid carbon dioxide, and liquid nitrous oxide. The fluid supply structure and instrument fluid supply structure may include an insulating layer made from insulating material and / or a vacuum jacket to prevent other parts of the device from being cooled by the cryogen. This may also ensure that only the tissue in the treatment zone is frozen and that other parts of the patient, which may be in close proximity to the cryogen delivery line, are not affected by the cryogen.

[0106] In one embodiment, the fluid supply module 220 includes one or more sensors that monitor the operation of different elements of the fluid supply module 220 and send measurements to the controller module 212. As described above, the controller module 212 (via a watchdog) can then compare these measurements to acceptable pre-set limits and generate an alarm signal if any one of these different elements develops a fault.

[0107] The structure for transmitting the fluid may be separate from the structure used to deliver the electromagnetic signal. However, in some circumstances, it may be desirable for these structures to be included within the same physical structure, such as, for example, a cable assembly. For example, it is advantageous to be able to use the same instrument that delivers RF and / or microwave energy to deliver the fluid, since contraction may occur (e.g., due to fluid leakage or loss of ventilation) when a separate instrument is introduced into the area or during the treatment. Being able to introduce the fluid using the same treatment structure allows the water level to rise as soon as possible when contraction occurs. Moreover, the use of a single instrument to introduce the fluid as well as perform the desiccation or dissection also reduces the time required to perform the overall procedure, reduces the risk of causing harm to the patient, and reduces the risk of infection. More generally, injection of fluid may be used to flush the treatment area, such as to remove waste or removed tissue to provide better visibility when treating. This may be particularly beneficial in endoscopic procedures. In one embodiment, the feeding structure of the present invention comprises the feeding structure disclosed in WO2012 / 095653, which is incorporated herein by reference.

[0108] The electrosurgical capsule 116 shown in FIG. 4 illustrates one specific embodiment of a modular configuration. However, it can be understood that the functionality of the electrosurgical capsule 116 can be altered by adding or removing certain optional modules to the core modules. As described above, the core modules are the controller module 212, the signal generator module 214, and the power supply structure module 214. These core modules provide a mechanism for controllably generating an EM signal for treating biological tissue and delivering the EM signal to the electrosurgical instrument. The EM signal may be any type of electromagnetic signal, such as RF or microwave. Furthermore, this primary functionality can be complemented in different ways to provide additional functionality. For example, a signal detector module 218 can be provided to monitor the condition of the tissue to determine tissue characteristics or to allow treatment (e.g., EM signals) to be tailored to the tissue. The signal detector module 218 can use the signal generator module 212 to provide a measurement signal (e.g., a low power microwave signal), but can also use a separate additional signal generator module 222 to generate the measurement signal. Additionally or alternatively, one or more additional signal generators 222 may be provided so that the capsule can deliver EM signals having multiple different frequencies. In one example, both RF EM signals and microwave EM signals may be provided by the capsule. In another example, microwave EM signals of multiple different frequencies may be provided. Furthermore, the powering structure module 216 may be configured to deliver one or more of the multiple different EM signals to the surgical instrument 114 separately or simultaneously. Finally, a fluid supply module 220 may be provided to deliver / receive fluid to / from the treatment site. For example, a gas in combination with RF or microwave energy may be provided to generate plasma. Alternatively, a tissue freezing fluid may be delivered with EM energy to perform cryoablation. Additionally, liquid may be extracted from the treatment site (e.g., by suction or pumping).

[0109] The electrosurgical capsule 116 of FIG. 4 includes a remote computing device 210 that communicates wirelessly with a controller module 212. The controller module 212 can communicate with and control each of the other modules of the electrosurgical capsule 116 via control commands. For example, the controller module 212 can issue a control command to the signal generator module 214 to generate an EM signal. The controller module 212 can issue a control command to the power supply structure module 216 to tune a signal channel by varying its adjustable impedance element. In either case, as described above, the controller module 212 can generate the control commands itself, but the controller module 212 may simply forward the control commands it receives from the remote computing device 210. Thus, in one embodiment, control of the system 200 is centralized at the remote computing device 210, and the controller module 212 may only forward control commands to the modules and may not generate or process data received from the remote computing device 210. However, in another embodiment, the controller module 212 may perform at least a portion of the control of the capsule 116, and thus the control of the capsule 116 may be shared between the remote computing device 210 and the controller module 212. In this hybrid configuration, the control of the capsule 116 may still be centralized in the remote computing device 210, and the controller module 212 may supplement this control only in certain circumstances, for example, when communication between the remote computing device 210 and the controller module 212 breaks down. Alternatively, the control of the capsule 116 may be centralized in the controller module 212, and the remote computing device 210 may supplement this control only in certain circumstances, for example, when user input is required. Thus, in summary, the overall control of the capsule 116 may be controlled by either or both of the remote computing device 210 and the controller module 212.

[0110] As mentioned above, the electrosurgical capsule 116 may be fully powered by a local battery or DC power source from the robotic arm to which it is attached. In other words, the electrosurgical capsule does not require a dedicated connection to an external mains power source. This may be desirable as it removes the need to consider measures to isolate the mains power source from the surgical instruments and ultimately from the patient. Figures 5-8 show a circuit by which a DC signal may be available at the amplification unit for a microwave signal generating module suitable for use in the electrosurgical capsule 116 described herein.

[0111] FIG. 5 is a schematic diagram of a microwave generating module that may be used as the signal generating module 214 of the type shown in the configuration shown in FIG.

[0112] The signal generation module 214 receives DC power as an input on a DC supply line 308. The DC power is received at a signal conditioning unit 316 which functions to launch a DC signal onto the common transmission line structure 306. For example, a voltage V of 24 V may be DD A DC signal having

[0113] The signal generation module 214 further includes a microwave source 314 configured to launch a microwave signal 310 into the common transmission line structure 306, which in this example is a coaxial transmission line. The microwave signal generator 314 is described below with reference to Figure 6. The microwave signal 310 from the microwave signal generator 314 is coupled to the coaxial transmission line via a capacitor 312 which acts as a DC isolation barrier to prevent DC signals from leaking into the microwave signal generator 314.

[0114] Advantageously, the DC signal is launched on the inner conductor of the coaxial transmission line carrying the microwave signal 310. However, in other examples, a separate elongated conductor (e.g., a wire) for carrying the DC signal may be provided.

[0115] The transmission line structure 306 conveys the DC signal and the microwave signal 310 to the amplification unit 304 which functions to amplify the microwave signal 310 to a power level suitable for treatment. The amplified microwave signal 318 is output by the amplification unit 304 and coupled to the feeding structure module 216 via a capacitor 319, from which it is delivered to the surgical instrument 114. The capacitor 319 acts as a DC barrier between the feeding structure module 216 and the amplification unit 304 to prevent the DC signal from reaching the instrument.

[0116] The amplification unit 304 includes a power amplifier 320, for example a power MOSFET, which receives as an input a microwave signal 322 output from a coaxial transmission line. The input to the power amplifier 320 is protected from DC signals by a capacitor 324.

[0117] The amplification unit 304 is arranged to separate DC power from the microwave signal and apply it across a power amplifier 320. The amplification unit 304 separates the DC power from the microwave signal (V DD ) is applied to the power amplifier 320. The microwave signal 322 may be blocked from the voltage rail 326 by a filtering array 328, which may include a pair of quarter wavelength stubs, as described in more detail below. Similarly, a filtering array 330 may be disposed at the connection between the voltage rail 326 and the power amplifier 320 to prevent microwave energy from leaking out of the power amplifier 320 onto the voltage rail 326.

[0118] The amplifier unit 304 controls the bias voltage V applied to the gate of the power amplifier 320. GG from the DC signal. The gate voltage extraction module 332 may include a DC-DC converter that down-converts the DC signal voltage to a level suitable for the power amplifier 320.

[0119] The distal amplifier section 304 may further include a gate control module 334 for controlling application of a gate voltage to the power amplifier 320. As described in more detail below, the gate control module 334 may operate to switch between two bias voltage states corresponding to an on (conducting) state and an off (non-conducting) state, respectively, of the power amplifier 320. The gate control module 334 may operate to introduce a time delay between application of a DC signal across the power amplifier 320 (i.e., as its drain voltage) and application of a bias voltage to turn on the power amplifier 320, to ensure smooth initialization of the amplification process.

[0120] To prevent microwave energy from leaking from the power amplifier 320 to the gate control module 334 , a filtering arrangement 336 may be disposed at the connection between the gate control module 334 and the gate of the power amplifier 320 .

[0121] The detailed structure of the gate voltage extraction module 332 and the gate control module 334 will be described below with reference to FIG.

[0122] In use, the microwave generation module thus provides amplification of a low power microwave signal to a therapeutically suitable power level, which may be an order of magnitude or more higher than the power level output by the microwave source 314, e.g., 10 W or more.

[0123] Figure 6 is a schematic diagram showing further details of the signal conditioning unit 316 and microwave source 314 configured to launch microwave and DC signals into the proximal end of a coaxial transmission line 370. Features in common with Figure 5 are numbered the same and will not be described again. The coaxial transmission line 370 includes an inner conductor 372 separated from an outer conductor 376 by a dielectric material 374. The coaxial transmission line 370 may be, for example, a Sucoform cable manufactured by Huber+Suhner.

[0124] 6 shows the components of the microwave signal generator 314. In this example, the microwave signal generator 314 has a microwave frequency source 378 followed by a variable attenuator 380 that may be controlled by the controller module 212 of the electrosurgical capsule. The output of the variable attenuator 380 is input to a signal modulator 382 that may be controlled by the controller module 212 to apply, for example, a pulsed waveform to the microwave signal. The output from the signal modulator 382 is input to a drive amplifier 384 to generate a microwave signal at a desired power level for input to the amplification unit 304. The microwave signal is coupled to a coaxial transmission line 370 via a capacitor 312.

[0125] The signal conditioning unit 316 for the DC signal includes a section of a microstrip transmission line 388 in which a low pass filter 390 is provided to prevent back transmission of the microwave signal to the input connector where the DC signal is received. The low pass filter 390 includes a pair of quarter wavelength stubs 392, 394 on the microstrip transmission line 388. The first stub 392 is spaced a half wavelength (i.e.

[0126]

number

[0127] ), where λ is the wavelength of the microwave signal on the microwave transmission line 388, and n is an integer equal to or greater than 1. This allows the first quarter wavelength (i.e.

[0128]

number

[0129] ) stub 392 is shorted at its base, thus ensuring that the other end of the quarter-wave stub 392 is open circuited. A second quarter-wave stub 394 is spaced a half-wave (i.e.

[0130]

number

[0131] ) The signal conditioning unit 316 may further include a set of capacitors 387 shunt-connected to the transmission line carrying the DC signal to remove other unwanted AC elements on the DC signal path.

[0132] 7 is a schematic circuit diagram showing an amplifier unit 304 for an embodiment of the present invention. Features in common with previous figures are given the same reference numbers and will not be described again.

[0133] In this example, the distal end of the transmission line structure 306 provides an input to the amplification unit 304. The transmission line structure 306 may include the coaxial transmission line 370 described above that carries both microwave and DC signals. The amplification unit 304 splits the microwave signal from the DC signal using a filter. The DC signal travels to the DC rail 326 via a first connection line 502 that has a low pass filter that includes a pair of quarter wavelength stubs 328 positioned to prevent the microwave signal from passing through.

[0134] The pair of stubs 328 may be fabricated on a microstrip transmission line. The first stub is located half a wavelength (i.e.

[0135]

number

[0136] ), where λ is the wavelength of the microwave signal on the microwave transmission line, and n is an integer equal to or greater than 1. This allows the first quarter wavelength (i.e.

[0137]

number

[0138] ) stub is shorted at its base, thus ensuring that the other end of the quarter-wave stub is open circuited. The second quarter-wave stub is then spaced a half-wave (i.e.

[0139]

number

[0140] ) apart. Meanwhile, the microwave signal travels along connection line 504 to power amplifier 320 where it becomes the input signal to be amplified. Connection line 504 may be a microstrip transmission line or the like. Connection line 504 includes capacitor 324 into which the microwave signal is coupled but which blocks DC signals. Capacitor 324 thus isolates power amplifier 320 from any DC components transmitted from coaxial transmission line 370.

[0141] A connection line 506 connects the voltage rail 326 to the power amplifier 320 to apply a DC signal voltage across the power amplifier 320 (i.e., as a drain supply). A pair of quarter wavelength stubs 330 are arranged as a low pass filter to prevent microwave energy from leaking out of the power amplifier 320 on the connection line 506. The pair of stubs 330 may be arranged in a similar manner as the stubs 328, but with respect to the connection point between the connection line 506 and the power amplifier 320.

[0142] The connection line 506 further includes a set of capacitors 508 shunt-connected to the connection line carrying the DC signal to eliminate other unwanted AC components on the DC signal path.

[0143] The connecting line 506 further includes an inductor 510 connected in series between the power amplifier 320 and the voltage rail 326. This inductance further reduces leakage of AC signals to the voltage rail 326.

[0144] Each of the above mentioned connection lines may be implemented as a suitable transmission line for carrying DC or microwave signals as required, such as a microstrip line on a flexible substrate that can be packed into a compact configuration.

[0145] In this embodiment, the amplifier unit 304 receives a bias voltage V for the power amplifier from a voltage rail 326. GG 5. The voltage rail 326 may be a relatively high voltage, e.g., 24V or a similar voltage, while the bias voltage for the power amplifier 320 may need to be an order of magnitude lower. To obtain the bias voltage, the distal microwave amplification module 304 includes a gate voltage extraction module 332. The gate voltage extraction module 332 functions as a DC-DC converter, and in this embodiment is implemented as a pair of parallel step-down converters 512, 514, each of which is configured to output a different voltage, allowing the bias voltage to be switched between two different states.

[0146] Each buck converter 512, 514 is connected to the voltage rail 326 to provide an input voltage. The capacitance and inductance values ​​in each buck converter 512, 514 are selected to convert the input voltage to a desired output voltage. The output voltage may be selected based on the operating characteristics of the power amplifier. In this example, the buck converters 512, 514 are configured to generate a negative output voltage by using diodes to control the appropriate current flow direction in each converter. This means that the output voltage (bias voltage) can be set close to the point of its characteristic where the power amplifier is conducting.

[0147] For example, the first buck converter 512 may be configured to output a bias voltage in the non-conducting portion of the power amplifier characteristic, e.g., −6 V. The second buck converter 514 may be configured to output a bias voltage in the conducting portion of the power amplifier characteristic, preferably just after the transition to the conducting state, e.g., −2 V.

[0148] The outputs from the pair of buck converters 512, 514 are connected to respective input poles of a switch 516 which forms part of the gate control module 334. The output of the switch 516 is connected to a connection line 518 which is connected to the connection line 504 for providing a bias voltage from the gate voltage extraction module 332 to the gate of the power amplifier 320.

[0149] A pair of quarter wavelength stubs 336 are positioned as a low pass filter to prevent microwave energy from leaking out of power amplifier 320 on connection line 518. The pair of stubs 336 may be positioned in a similar manner as stub 328, but with respect to the connection point between connection line 518 and connection line 504.

[0150] The connection line 518 further comprises a set of capacitors 520 shunt-connected to the connection line 518 carrying the bias voltage to eliminate other unwanted AC components on the bias voltage signal path.

[0151] The gate control module 334 operates to apply the required bias voltage to the gate of the power amplifier 320. Thus, the gate control module 334 effectively operates to selectively activate the power amplifier 320. In this example, the gate control module 334 functions to control a switch 516 that selects the buck converter 512, 514 to provide the bias voltage to the power amplifier 320. The switch 516 may be controlled by an inductor 522 that is energized upon application of a DC signal to the voltage rail 326. Thus, the switch 516 may adopt a default (e.g., off) configuration when the inductor 522 is not energized. In this configuration, the switch 516 connects the buck converter at a non-conducting voltage level (e.g., −6V) to the power amplifier. When the inductor 522 is energized, the switch adopts an activated (e.g., on) configuration and the buck converter at a conducting voltage level (e.g., −2V) is connected to the power amplifier.

[0152] In this embodiment, the gate control module 334 includes a "soft start" circuit 524 for the power amplifier 320, which acts to delay the switch state change by smoothly increasing the voltage applied to the inductor 522. The advantage of this configuration is that it allows the drain voltage across the power amplifier 320 to reach a steady state before a bias voltage is applied to activate the power amplifier. The "soft start" circuit 524 is implemented using a comparator 526 that generates an output to the inductor 522 based on the difference between a varying first input from an RC circuit 528 and a fixed input from a voltage divider circuit 530.

[0153] 8 is a schematic diagram showing another example of a signal generator module 214 configured as a microwave amplifier. Features in common with FIG. 5 are given the same reference numbers and will not be described again.

[0154] The signal generator module 214 of FIG. 8 differs from the signal generator module of FIG. 5 in that the gate voltage is generated at the proximal end and transferred through the transmission line 306 as a secondary DC signal.

[0155] In this configuration, the received DC signal (for example, the voltage V DD 8. The input signal (having the signal sigma 320 and sigma 322) may be transmitted to the amplifier unit 304 by a dedicated transmission line 371. In the amplifier unit 304, the distal end of the transmission line 371 is coupled to the drain of the power amplifier 320 through a low pass filter 330, which may be of the type described above. The dedicated transmission line 371 may be connected directly to the drain through the low pass filter or may be connected through a voltage rail 326 as shown in FIG.

[0156] In this configuration, the means for generating a bias voltage for the power amplifier may be disposed at the proximal end of the transmission line 306. For example, a gate voltage extraction module 332 may be configured for operation in the same manner as described above, and a gate control module 334 may be provided to control the bias voltage supplied to the transmission line 306.

[0157] In this example, the bias voltage is transmitted to the distal portion through the inner conductor of a coaxial transmission line 370 in the cable assembly 306. The coaxial transmission line 370 is also used to transmit the microwave signal 310 from the microwave signal generator 314.

[0158] In some examples, a dedicated line 371 for the DC signal may be an additional conductive layer formed around the outer conductor of the coaxial transmission line 370 and separated therefrom by an insulating layer, for example, to effectively form a signal triaxial cable. In this example, it may be desirable to include a low pass filter in the amplification unit 304 at the point where the DC signal is separated from the coaxial transmission line 370 to avoid the microwave signal leaking onto the voltage rail 326.

[0159] 9 is a schematic cross-sectional view through an electrosurgical instrument 114 that can be addressed by an articulating robotic arm in one embodiment of the present invention. The electrosurgical instrument 114 can be connectable to the electrosurgical capsule 116 via the articulating robotic arm in the manner described above. The electrosurgical instrument 114 is arranged or configured to deliver EM radiation from a distal instrument tip (or distal assembly) 136 to treat biological tissue located at a treatment site at or near the distal assembly. The electrosurgical instrument 114 can be any device arranged to use EM energy (e.g., RF energy, microwave energy) for the treatment of biological tissue during use. The electrosurgical instrument 114 can use EM energy for any or all of extraction, coagulation, and ablation. For example, the instrument 114 can be an extraction device, a pair of microwave forceps, or a snare that emits microwave energy and / or couples RF energy, and an argon beam coagulant.

[0160] The electrosurgical instrument 114 includes an instrument feed structure 140 for transmitting EM radiation (e.g., an EM signal) to the distal end 138. In this example, the feed structure 140 is a coaxial transmission line formed from an inner conductor 142 separated from an outer conductor 146. The inner conductor 142 is hollow to define a passageway 148 for delivering a fluid.

Claims

1. A robotic assisted surgery system (100), comprising: an electrosurgical generator unit (116); an electrosurgical instrument (114); A robotic surgical tool (102), comprising: An articulated arm (110); An instrument holder (112), a proximal portion (113) attachable to and operable by said articulating arm, said proximal portion configured to receive a power input (124) transmitted through said articulating arm; a distal portion (117) configured to hold said electrosurgical instrument; a middle portion (115) configured to receive said electrosurgical generator unit; The instrument holder (112) comprises a body having and the robotic surgical tool comprising: the electrosurgical generator unit is removably mountable to the instrument holder; The electrosurgical generator unit comprises: A housing (200); an input connector (206) having a power coupling unit configured to receive power via the instrument holder; a signal generator (214) enclosed within the housing, the signal generator configured to generate an electrosurgical signal; an energy delivery structure (216) configured to transmit the electrosurgical signal to an output port (132) of the intermediate section, the electrosurgical signal being deliverable from the intermediate section to the electrosurgical instrument via a transmission line (134) disposed within the instrument holder; The robot-assisted surgery system.

2. The robotic assisted surgery system of claim 1 , wherein the intermediate portion (115) comprises a recess, and the housing (200) is removably mountable in the recess (126).

3. 2. The robotic-assisted surgery system of claim 1, wherein the intermediate portion includes a plurality of recesses, each recess configured to receive a respective electrosurgical generator unit, and the intermediate portion configured to transmit one or more electrosurgical signals from the electrosurgical generator units to the electrosurgical instrument.

4. 4. The robotic assisted surgery system of claim 1, wherein the electrosurgical generator unit further comprises a controller (212) encased within the housing and connected to the signal generator, the controller configured to receive a control signal and to control the signal generator based on the received control signal.

5. 5. The robotic surgical system of claim 4, wherein the electrosurgical generator unit further comprises an input portion (202) communicatively connectable to a control network of the robotic surgical system, the controller being configured to receive the control signal from the control network of the robotic surgical system via the input portion (202).

6. The robotic-assisted surgery system of claim 4 , wherein the controller includes a wireless communication module configured to wirelessly receive the control signal.

7. The robotic assisted surgery system of any one of claims 1 to 6, wherein the electrosurgical generator unit further comprises a fluid source (224) and a fluid conduit (226) configured to couple fluid from the fluid source to the robotic assisted surgery system.

8. 8. The robotic-assisted surgery system of claim 7, wherein the energy delivery structure (216) comprises a coaxial transmission line having an inner conductor separated from an outer conductor by a dielectric material, and the fluid conduit comprises a passageway formed within the inner conductor.

9. 9. The robotic assisted surgery system of claim 1, wherein the electrosurgical generator unit further comprises a signal detector (218) encased within the housing and connected to the energy delivery structure, the signal detector configured to sample a signal characteristic at the energy delivery structure and generate a detected signal indicative of the signal characteristic.

10. The robotic assisted surgery system of claim 1 , wherein the power supply is a DC signal, and the signal generator is configured to generate the electrosurgical signal using the DC signal.

11. The robotic assisted surgery system of any one of claims 1 to 10, wherein the electrosurgical generator unit further comprises a battery (213) encased within the housing, the battery being configured as an internal power source for the electrosurgical generator unit.

12. The robotic assisted surgery system of any one of claims 1 to 11, wherein the signal generator comprises a microwave source (314) and an amplification unit (304) coupled to the microwave source, and the electrosurgical signal comprises a microwave signal (318).

13. The robotic assisted surgery system of any preceding claim, wherein the signal generator comprises a radio frequency (RF) signal generator and the electrosurgical signal comprises an RF signal.

14. 14. The robotic assisted surgery system of claim 1, wherein the electrosurgical instrument comprises an elongate probe having a proximal energy transmission structure and a distal tip, and the instrument holder is configured to couple the electrosurgical signal to the proximal energy transmission structure for delivery to the distal tip.

15. 15. The robotic assisted surgery system of claim 14, further comprising a control console connected to the articulating arm via a control network, the control console configured to control the electrosurgical generator unit using control signals transmitted over the control network.

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