Method and system for estimating temperature of end effector of ultrasonic instrument

Abstract

A method performed by a surgical system. The method determines a resonant frequency of an end effector of an ultrasonic instrument and determines whether the end effector of the ultrasonic instrument is in a heated state or a cooled state. In response to determining that the end effector is in a heated state, the method estimates a temperature of the end effector based on an output of a first temperature model having an input based on the resonant frequency. However, in response to determining that the end effector is in a cooled state, the method estimates a temperature of the end effector based on an output of a second temperature model having an input based on the resonant frequency. The method presents a notification based on the estimated temperature.

Description

Technical Field

[0001] Various embodiments of this disclosure relate generally to surgical systems, and more specifically to surgical systems for estimating the temperature of an end effector of an ultrasound instrument. Other embodiments are also described. Background Technology

[0002] Minimally invasive surgical procedures (MIS), such as laparoscopic surgery, utilize techniques designed to minimize tissue damage during surgical procedures. Laparoscopic procedures typically require multiple small incisions inside the patient (e.g., in the abdomen) through which several surgical instruments (such as endoscopes, scalpels, graspers, and needles) are inserted. Gas is injected into the abdomen, inflating it and providing more space around the ends of the instruments, making it easier for the surgeon to see (via the endoscope) and manipulate tissue at the surgical site. MIS can be performed more quickly and with less surgeon fatigue using surgical robotic systems, in which surgical instruments are operatively attached to the distal end of a robotic arm, and the control system actuates the arm and its attached instruments. As the surgeon manipulates a handheld user input device (UID), the end of the instrument simulates its position and orientation movements. Surgical robotic systems can have multiple surgical arms, one or more of which have attached endoscopes, and other surgical arms with attached surgical instruments for performing certain surgical actions.

[0003] Control input from a user (e.g., a surgeon or other operator) is captured via one or more user input devices and then translated into control of the robotic system. For example, when a surgical instrument is positioned at a surgical site on a patient, an instrument driver with one or more motors can actuate one or more degrees of freedom of the surgical instrument in response to a user command. Summary of the Invention

[0004] Surgical instruments used in some MIS procedures are ultrasonic devices that use ultrasonic vibrations at their tips to rapidly generate heat for cutting and cauterizing tissue. The tip may include a blade that reaches a high temperature (e.g., greater than 300°C) during a “heating” cycle (or state) in which the blade oscillates against a tissue mass, thereby generating heat during oscillation due to friction between the blade and the tissue. Specifically, the system can activate the instrument in response to user input from the operator (such as when the user presses a pedal or button), thus putting the blade into the heating cycle. After reaching the high temperature, the blade can be used to cut a portion of the tissue while simultaneously sealing the remaining tissue. By performing multiple tasks (e.g., cutting, cauterization, etc. for dissection), the use of instruments during laparoscopic surgery reduces the number of instrument changes and instruments required during the procedure.

[0005] After using an ultrasound device in its heated state, the operator can stop providing user input (e.g., releasing a pedal or button) to deactivate the device and allow the blade to cool. However, the rate of blade cooling during this time remains unknown to the operator. Therefore, the blade may remain at a high temperature (e.g., above a threshold temperature), which may be too hot to contact an object (such as human tissue) during the cooling period. Furthermore, this time period can vary based on the blade's last temperature when the device is in a heating cycle (e.g., up to at least thirty seconds). This results in inefficiency in device use, and conventional systems cannot actively control the ultrasound device to maintain the blade temperature at or below the desired temperature when the blade temperature cannot be monitored between cycles.

[0006] This disclosure provides a laparoscopic surgical system that uses different temperature models to effectively estimate the temperature of an ultrasonic instrument during (and between) heating and cooling cycles of the instrument. Specifically, when the instrument is used to dissect tissue, the system activates the instrument into a heating cycle by providing power (e.g., in response to user input from the operator, such as pressing a pedal or button) to oscillate the instrument's blade. While the instrument is active in this "high-power" state, the system can determine the blade's temperature using a heating temperature model based on one or more characteristics of the instrument (e.g., input voltage, input current, resonant frequency, etc.). After the heating cycle terminates (e.g., the operator releases the pedal), the system can enter a "low-power" state (or cooling cycle), in which the ultrasonic instrument draws less power (e.g., is supplied with less current) to cause the blade to vibrate less compared to when the instrument is in the high-power state. When in this low-power state, the instrument may not draw enough power to generate frictional heat (e.g., because the blade vibrates at a lower offset than required to generate heat), but it may have enough power to determine one or more characteristics of the instrument, such as the resonant frequency of the blade, which the system can use to estimate the temperature of the ultrasonic instrument using a cooling temperature model. Therefore, the system can provide the operator with temperature readings based on (e.g., continuous) temperatures estimated using different models during ultrasonic instrument transitions between heating and cooling cycles.

[0007] This disclosure provides a surgical system that estimates the temperature of an end effector when it is used by an operator, for example, for displaying to the operator. Specifically, the system determines one or more characteristics of the end effector, such as the resonant frequency of the end effector, and determines whether the end effector is in a heated or cooled state. For example, the resonant frequency may be the frequency at which the end effector (e.g., the blade of the end effector) vibrates when it enters a heated or cooled state (or as the end effector enters a heated or cooled state). In response to determining that the end effector is in a heated state, the system may estimate the temperature of the end effector based on the output of a first temperature model, which has an input based on the resonant frequency. However, in response to determining that the end effector is in a cooled state, the system may estimate the temperature of the end effector based on the output of a second (or cooled) temperature model, which has an input based on the resonant frequency. The system may present a notification based on the estimated temperature. For example, the system may display a pop-up notification on a display including the estimated temperature. Thus, the system is able to estimate the temperature of the end effector between different states (e.g., when an operator uses the end effector during surgery) in a coherent and efficient manner.

[0008] In one embodiment, the resonant frequency is a first resonant frequency at the start time when the end effector enters a heating or cooling state, wherein the system determines the initial temperature of the end effector at the start time; and determines a second resonant frequency of the end effector of the ultrasonic instrument at a time after the start time. In another embodiment, the temperature is estimated based on the initial temperature, the first resonant frequency, and the second frequency. In some embodiments, estimating the temperature in response to determining that the end effector is in a heating state includes determining the temperature change of the end effector based on the difference between the first resonant frequency and the second frequency; and combining the temperature change with the initial temperature.

[0009] In one embodiment, estimating the temperature in response to determining that the end effector is in a cooled state includes: determining whether the end effector is being cooled by air or by contact cooling; estimating the temperature of the end effector based on the output of a first cooling temperature model in response to determining that the end effector is being cooled by air; and estimating the temperature of the end effector based on the output of a second cooling temperature model in response to determining that the end effector is being cooled by contact. In another embodiment, the first cooling temperature model is a polynomial model, and the second cooling temperature model is an exponential model.

[0010] In one embodiment, the resonant frequency is a first resonant frequency, wherein estimating the temperature of the end effector based on the output of the second temperature model includes: determining model coefficients of the second temperature model based on the first resonant frequency; determining the second resonant frequency of the end effector of the ultrasonic instrument; and determining the temperature by applying the second resonant frequency and the coefficients to the second temperature model. In another embodiment, the system determines the impedance of the end effector based on the input current of the ultrasonic instrument; and determines a corrected resonant frequency based on the impedance and the second resonant frequency. In some embodiments, determining the temperature of the end effector based on the output of the second temperature model includes applying the corrected resonant frequency as input to the second temperature model.

[0011] In one embodiment, the system determines the input current being supplied to the ultrasonic instrument, wherein determining whether the end effector is in a heated or cooled state includes: determining that the end effector is in a heated state when the input current is greater than (or equal to) a current threshold; and determining that the end effector is in a cooled state when the input current is less than the current threshold. In another embodiment, the system determines the impedance of the end effector based on the input current; determines that the end effector is in a cooled state when in air in response to determining that the impedance is greater than a threshold; and determines that the end effector is in a cooled state when in contact with an object in response to determining that the impedance is less than a threshold.

[0012] The foregoing summary does not include an exhaustive list of all embodiments of this disclosure. It is contemplated that this disclosure encompasses all systems and methods that can be implemented by all suitable combinations of the various embodiments outlined above, as well as those disclosed in the detailed description below and specifically pointed out in the claims. Such combinations may have specific advantages not specifically described in the foregoing summary. Attached Figure Description

[0013] The embodiments are illustrated in the figures by way of example rather than limitation, wherein similar reference numerals indicate similar elements. It should be noted that references to "an" or "one" embodiment of this disclosure do not necessarily refer to the same embodiment, and that they refer to at least one. Furthermore, for the sake of brevity and to reduce the total number of figures, a given figure may be used to illustrate features of more than one embodiment, and not all elements in the figures may be necessary for a given embodiment.

[0014] Figure 1 A drawing view of an example surgical system in an operating room is shown.

[0015] Figure 2 A drawing view of an ultrasound device and generator according to one embodiment of the present disclosure is shown.

[0016] Figure 3 It shows Figure 2End effector of an ultrasonic instrument.

[0017] Figure 4 It is a block diagram of a surgical system based on an implementation plan.

[0018] Figure 5 This is a flowchart of one implementation of a process for estimating the temperature of the end effector of an ultrasonic instrument.

[0019] Figure 6 This is a flowchart of one embodiment of a process for estimating the temperature of the end effector of an ultrasonic instrument when the end effector is in a heated state.

[0020] Figure 7 This is a flowchart of one embodiment of a process for estimating the temperature of the end effector of an ultrasonic instrument when the end effector is in a cooled state.

[0021] Figure 8 This is a flowchart of another embodiment of the process for estimating the end effector temperature of an ultrasonic instrument when the end effector is in a cooled state.

[0022] Figure 9 Several stages of a display of a surgical system are shown, which displays actions performed by an end effector of an ultrasonic instrument and shows the temperature of the end effector.

[0023] Figure 10 This is a flowchart of another implementation of the process for estimating the temperature of the end effector of an ultrasonic instrument. Detailed Implementation

[0024] Several embodiments of this disclosure will now be explained with reference to the accompanying drawings. Where the shape, relative positions, and other embodiments of the parts described in a given embodiment are not explicitly defined, the scope of this disclosure is not limited to the parts shown, which are shown for illustrative purposes only. Furthermore, while numerous details are set forth, it should be understood that some embodiments may be practiced without these details. In other instances, well-known circuits, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification. Moreover, unless the meaning explicitly states otherwise, all scopes listed herein are to be considered to include the endpoints of each scope.

[0025] Figure 1 A drawing view of an example (e.g., laparoscopic) surgical system (hereinafter referred to as "the System") 1 in an operating room is shown. System 1 includes a user console 2, a control tower 3, and one or more surgical robotic arms 4 located at a surgical robotic operating table (surgical table or surgical platform) 5. In one embodiment, the arms 4 may be mounted to, for example... Figure 1The example shows the operating table or bed where the patient is situated. In one embodiment, at least some of the arms 4 may be configured differently. For example, at least some of the arms may be mounted on a ceiling, sidewall, or another suitable structural support (such as a trolley separate from the operating table). System 1 may incorporate any number of devices, tools, or accessories for performing surgery on patient 6. For example, system 1 may include one or more surgical instruments 7 for performing surgical procedures (surgical protocols). Surgical instruments 7 may be end effectors attached to the distal end of surgical arms 4 for performing surgical protocols.

[0026] Each surgical tool 7 can be manually manipulated, robotically manipulated, or both during surgery. For example, a surgical tool 7 can be a tool for accessing, viewing, or manipulating the internal anatomy of a patient 6. In one embodiment, the surgical tool 7 is a gripper capable of grasping the patient's tissues. The surgical tool 7 can be manually controlled by a bedside operator 8; or it can be robotically controlled via actuated movement of a surgical robotic arm 4 to which it is attached. For example, when manually controlled, the operator can (e.g., physically) hold a portion of the tool (e.g., a handle) and can manually control the tool by moving the handle and / or pressing one or more input controls (e.g., buttons) on the tool (e.g., the handle of the tool). In another embodiment, when robotically controlled, the surgical system can manipulate the surgical tool based on user input (e.g., received via a user console 2, as described herein).

[0027] Generally, a remote operator 9 (such as a surgeon or other operator) can use the user console 2 to remotely manipulate the arm 4 and / or attached surgical instruments 7, for example, during remote operations. The user console 2 may be located in the same operating room as the rest of the system 1, such as... Figure 1As shown. However, in other environments, the user console 2 may be located in an adjacent or nearby room, or it may be located in a remote location, such as in different buildings, cities, or countries. The user console 2 may include one or more components, such as a seat 10, one or more foot controls (or foot pedals) 13, one or more (handheld) user input devices (UIDs) 14, and at least one display 15. The display is configured to display, for example, a view of a surgical site within the patient 6. The display may be configured to display image data (e.g., still images and / or videos). In one embodiment, the display may be any type of display, such as a liquid crystal display (LCD), a light-emitting diode (LED) display, an organic LED (OLED) display, etc. In some embodiments, the display may be a 3D immersive display for displaying 3D (surgical) presentations. For example, during a surgical procedure, one or more endoscopic cameras may capture image data of the surgical site, and the display may present this image data to the user in 3D. In one embodiment, the 3D display may be an automated stereoscopic display that provides 3D perception to the user without the need for special glasses. As another example, a 3D display can be a stereoscopic display that provides 3D perception by using glasses (e.g., via an active shutter or polarization).

[0028] In another embodiment, display 15 may be configured to display at least one graphical user interface (GUI) that provides information and / or interactive content to assist a user in performing surgical procedures using one or more instruments in surgical system 1. For example, some of the displayed content may include image data captured by one or more endoscopic cameras, as described herein. In another embodiment, the GUI may include selectable UI items that, when manipulated by a user, enable the system to perform one or more operations. For example, the GUI may include UI items as interactive content to switch control between robotic arms. In one embodiment, the system may include input devices (such as a keyboard, mouse, etc.) for interacting with the GUI. In another embodiment, a user may use UID 14 to interact with the GUI. For example, a user may manipulate the UID to navigate through the GUI (e.g., using a cursor), and make selections by hovering the cursor over a UI item and manipulating the UID (e.g., selecting a control or button). In some embodiments, the display may be a touch-sensitive display. In this case, the user may perform selections by navigating and selecting via the touch display. In some embodiments, any method may be used to navigate and / or select UI items.

[0029] As shown in the figure, the remote operator 9 sits in the seat 10 and views the user display 15 while manipulating the foot control 13 and the handheld UID 14 to remotely control one or more of the arm 4 and the surgical instrument 7 (which is mounted on the distal end of the arm 4).

[0030] In some variations, the bedside operator 8 can also operate the system 1 in a "bedside" mode, where the bedside operator 8 (the user) is now positioned to one side of the patient 6 and simultaneously manipulates robot-driven tools (end-effectors attached to arm 4), for example, holding a handheld UID 14 and a manual laparoscopic tool with one hand. For instance, the bedside operator's left hand can manipulate the handheld UID to control the robotic components, while the bedside operator's right hand can manipulate the manual laparoscopic tool. Therefore, in these variations, the bedside operator 8 can perform both robot-assisted minimally invasive surgery and manual laparoscopic surgery on the patient 6.

[0031] During the example procedure (surgical operation), patient 6 is prepared for surgery and anesthesia is administered by aseptically covering the patient with a sterile drape. Initial access to the surgical site can be manually performed (to facilitate access to the surgical site) while the arms of system 1 are in a retracted or withdrawn configuration. Once access is complete, initial positioning or preparation of system 1 (including its arms 4) can be performed. The surgical operation then continues, with the remote operator 9 at user console 2 using foot controls 13 and UID 14 to manipulate various end effectors and, possibly, imaging systems to perform the surgical procedure. Artificial assistance can also be provided at the operating table or surgical table by a bedside person (e.g., bedside operator 8) wearing sterile surgical gowns, who can perform tasks on one or more arms of robotic arms 4, such as tissue retraction, manual repositioning, and tool changes. Non-sterilized personnel may also be present to assist remote operator 9 at user console 2. When a procedure or surgical operation is completed, System 1 and User Console 2 can be configured or set to a certain state to facilitate the completion of postoperative procedures, such as cleaning or disinfection, and the input or printing of health records via User Console 2.

[0032] In one embodiment, a remote operator 9 holds and moves UID 14 to provide input commands, thereby driving one or more robotic arm actuators 17 (or drive mechanisms) in the (mobile) robot system 1 for remote operation. UID 14 may be communicatively coupled to the rest of system 1, for example, via a console computer system 16 (or host). UID 14 may generate spatial state signals corresponding to the movement of UID 14, such as the position and orientation of the UID's handheld housing, and the spatial state signals may be input signals for controlling the movement of the robotic arm actuators 17. System 1 may use control signals derived from the spatial state signals to control the proportional movement of the actuators 17. In one embodiment, a console processor of the console computer system 16 receives the spatial state signals and generates corresponding control signals. Based on these control signals controlling how the actuators 17 are energized to drive segments or connectors of the arm 4, the movement of a corresponding surgical tool attached to the arm can simulate the movement of UID 14. Similarly, the interaction between the remote operator 9 and UID 14 can generate, for example, a gripping control signal that causes the jaws of the gripper of the surgical tool 7 to close and grip the tissue of the patient 6.

[0033] System 1 may include a plurality of UIDs 14, wherein a corresponding control signal is generated for each UID that controls the actuators and surgical instruments (end-effectors) of the respective arm 4. For example, a remote operator 9 may move a first UID 14 to control the movement of an actuator 17 located in the left robotic arm, wherein the actuator responds by moving links, gears, etc. in the arm 4. Similarly, movement of a second UID 14 by the remote operator 9 controls the movement of another actuator 17, which in turn drives other links, gears, etc. in System 1. System 1 may include a right arm 4 fixed to a bed or table on the right side of the patient, and a left arm 4 located on the left side of the patient. The actuators 17 may include one or more motors controlled to drive the joints of the arm 4 to rotate, for example, to change the orientation of the endoscope or gripper of the surgical instrument 7 attached to the arm relative to the patient. The movement of a plurality of actuators 17 in the same arm 4 may be controlled by spatial state signals generated from a particular UID 14. The UID 14 may also control the movement of the corresponding surgical instrument gripper. For example, each UID 14 can generate a corresponding gripping signal to control the movement of an actuator (e.g., a linear actuator) that opens or closes the jaws of the gripper at the distal end of the surgical tool 7 to grip tissue in the patient 6.

[0034] In some implementations, communication between the surgical robot operating table 5 and the user console 2 may be conducted via a control tower 3, which translates user commands received from the user console 2 (and more specifically from the console computer system 16) into robot control commands sent to the arm 4 on the surgical table 5. The control tower 3 may also send status and feedback from the surgical table 5 back to the user console 2. The communication connection between the surgical table 5, the user console 2, and the control tower 3 may be via a wired link (e.g., fiber optic) and / or a wireless link, using any suitable data communication protocol among various wireless data communication protocols, such as Bluetooth. Any wired connection may optionally be integrated into the floor and / or walls or ceiling of the operating room. System 1 may provide video output to one or more displays, including displays within the operating room and remote displays accessible via the Internet or other networks. Video output or feeds may also be encrypted to ensure privacy, and all or part of the video output may be stored on a server or electronic healthcare record system.

[0035] Figure 2 A drawing view of an ultrasound device 20 and a generator 25 according to one embodiment of the present disclosure is shown. As shown, the ultrasound device may be a handheld laparoscopic tool configured to perform ultrasound surgical procedures or tasks, such as cutting, sealing (cauterizing) tissue, based on manual manipulation / manipulation of the instrument by an operator (e.g., a surgeon) (e.g., manual manipulation of the handle 21). For example, during a laparoscopic (or endoscopic) surgical procedure, a small incision may be made in the patient to form an opening (or orifice), through which the ultrasound device may be inserted into the patient's cavity (e.g., by blowing air into the cavity), wherein an end effector may be used by the operator to manipulate tissue and perform surgical procedures (e.g., cutting and / or cauterizing, etc.). The ultrasound device (e.g., via a cable) is coupled to a generator (as shown), which enables the ultrasound device to operate in one or more power states, as described herein.

[0036] According to various embodiments of the subject art, the ultrasound device includes a handle (e.g., which includes a tool driver) 21, a shaft (or sleeve) 22, and an end effector 23 (e.g., which can be coupled to the shaft of the device) that can be loaded into the sleeve.

[0037] Handle 21 may be arranged to be held by an operator and may allow the operator to manipulate the ultrasound instrument (e.g., the end effector 23 of the ultrasound instrument) during surgical procedures. In one embodiment, the handle may include one or more inputs (e.g., triggers, one or more buttons, etc.) that allow the operator to control the ultrasound instrument. For example, the instrument may include a trigger that, when pulled and held by one or more of the user's fingers, generates a control signal that allows the user to control the end effector of the instrument (and / or control a portion of the surgical system). Specifically, the trigger may be arranged to manipulate the end effector (e.g., by adjusting...). Figure 3 (The position of the articulated arm 31 shown). In another embodiment, the handle may include one or more inputs for changing the power state of the device. More details regarding the power state of the device are described herein.

[0038] As described herein, the handle may include a tool driver (not shown) that can be arranged to drive an end effector 23 of an ultrasonic instrument. Specifically, the tool driver may include a (e.g., linear) motor or actuator that can be arranged to vibrate (or oscillate) the end effector (e.g., the blade of the end effector) at one or more frequencies (e.g., at very high (ultrasonic) frequencies and / or at low frequencies). In some embodiments, the tool driver is configured to vibrate the end effector such that a portion of the end effector (e.g., the blade) moves back and forth along one or more axes. Specifically, the tool driver may vibrate the end effector within one or more offset ranges, wherein within each offset range, the end effector (e.g., the blade of the end effector) may be displaced at a (e.g., different) distance from the starting (or initial) position. Further information regarding how the end effector vibrates is described herein. In another embodiment, the tool driver may include an ultrasonic transducer configured to vibrate the end effector according to an input voltage / current (e.g., applied by generator 25).

[0039] As described herein, an ultrasonic instrument may include an end effector 23 and a handle 21 (which may include a tool driver). Specifically, the instrument has a handle 21, a shaft 22 coupled to a distal end of the handle, and an end effector 23 coupled to a distal end of the shaft. In this case, the ultrasonic instrument, as referenced herein, may be an end effector coupled to a handle (e.g., a tool driver coupled to the handle via the shaft 22). In one embodiment, the ultrasonic instrument (e.g., the end effector of the ultrasonic instrument) may be detachable from the handle (and removably coupled to the handle). In some embodiments, the shaft receives and guides a blade (e.g., the shaft of a blade) for coupling to the instrument.

[0040] As described herein, the surgical system 1 includes an ultrasound instrument 20 configured to generate heat based on vibrations of its end effector 23. In another embodiment, the instrument can be any type of energy (e.g., a laparoscopy) tool designed to generate heat.

[0041] As described herein, the ultrasound instrument 20 can be a handheld laparoscopic instrument that can be manually held and manipulated by an operator. In another embodiment, the instrument can be part of a surgical robotic arm. Specifically, the ultrasound instrument can be coupled to the robotic arm and powered by a generator, as described herein. For example, the ultrasound instrument can be coupled to the distal end of the robotic arm (e.g., Figure 1 The robotic arm 4 includes several components that allow the robotic arm to be controlled by an operator. For example, the surgical robotic arm 4 may include multiple connectors and multiple engagement modules for actuating the multiple connectors relative to each other. The engagement modules may include various engagement types, such as pitch engagements or roll engagements, which can substantially constrain the movement of adjacent connectors about certain axes relative to other axes. The multiple engagement modules of the robotic arm 4 can be actuated to position and orient an ultrasound instrument for use in robotic surgery. In one embodiment, the ultrasound instrument may be coupled to a distal end via a tool driver arranged as an end effector 23 to actuate the instrument.

[0042] When an ultrasound instrument is coupled to a robotic arm, the movement and manipulation of the ultrasound instrument can be performed via one or more user controls (e.g., UID, foot pedal, etc.) coupled to the surgical system. For example, the UID may be arranged to open / close the gripper (end effector 23) of the ultrasound instrument, and / or may be arranged to adjust the spatial position of the gripper (in space) based on user input (e.g., the position of the UID).

[0043] Turning Figure 3 The figure shows Figure 2 The figure shows an end effector 23 for an ultrasonic instrument. Specifically, the end effector is illustrated as a gripper (or gripping device) comprising a blade (or end) 30 as a jaw and an articulated arm (or jaw) 31 rotatably coupled to a joint (or robotic wrist) 32, which is coupled to the distal end of a shaft. In another embodiment, the end effector 23 (e.g., the joint 32 of the end effector) may be part of a portion (distal end) of a shaft 22. In another embodiment, the joint 32 may be part of the blade 30. In one embodiment, the gripper (or part of the gripper) is received via the shaft 22. For example, the blade may be received (and extend) through the shaft and arranged to be coupled at (or toward) the proximal end of the shaft to (e.g., a tool driver of a handle 21).

[0044] The articulated arm 31 (at the joint 32) can be rotatably coupled to the shaft 22, and the articulated arm can be arranged to rotate about a rotational (Z) axis (e.g., in the Z direction). Specifically, the gripper can be arranged to open and close based on the rotational position of the articulated arm about the rotational axis of the joint relative to the blade (and / or the shaft). For example, the gripper is arranged to open (or be in the open position) when the articulated arm rotates away from the blade (e.g., a threshold distance). When in this position, the end effector can be oriented, thereby allowing an object (such as tissue) to be positioned between the blade and the articulated arm (e.g., by moving the end effector about the object). When the articulated arm rotates toward the blade (e.g., within the threshold distance), the gripper can be closed (or be in the closed position), thereby allowing the gripper to hold the object between the blade and the articulated arm. As described herein, the articulated arm can be arranged to apply pressure against the grasped object (e.g., squeezing the object between the jaws) to grip the object and / or perform dissection on the object. In another embodiment, the articulated arm 31 may be rotatably coupled to a portion of the blade. In one embodiment, the blade 30 and the articulated arm may be received via a shaft, such that the arm (and / or the blade) is coupled to another shaft passing through shaft 22.

[0045] As described herein, the blade 30 can be the jaws of a gripper. Specifically, the blade is a jaw that cannot rotate relative to the end effector (e.g., about the Z-axis). The blade can be arranged to vibrate along its longitudinal (Y) axis (in the Y direction) to generate heat when the ultrasonic instrument is in a high-power (or heating) state (or mode). Specifically, the blade can be driven (e.g., by a tool driver of the handle 21) to move back and forth (e.g., linearly) along the longitudinal axis of the end effector (and through the axis, as described herein) so that the blade 30 is repeatedly displaced at a certain (e.g., constant) frequency. Specifically, the blade can vibrate (e.g., reciprocate) within an offset (or displacement) range, wherein the blade moves a certain distance from a starting position (e.g., forward or away from the end effector) and then moves that distance back. In one embodiment, the offset can be the distance the blade moves from the starting position to an extended position. In another embodiment, the offset can be the distance the blade moves forward and backward.

[0046] As described herein, the blade can generate frictional heat when vibrating against an object. Specifically, the blade can contact and vibrate against the tissue as the gripper compresses tissue between the two jaws 30 and 31. When the blade vibrates, the end effector can cut and / or cauterize the tissue, as described herein. In one embodiment, the blade can vibrate differently (e.g., within different offset ranges) based on the power state of the ultrasonic instrument (e.g., how much power is provided by the forward ultrasonic instrument). Further information regarding the power state of the vibrating blade and the ultrasonic instrument is described herein.

[0047] As described herein, the end effector 23 may be a gripper. In another embodiment, the end effector may be any type of tool that can be designed to be manipulated by an ultrasound instrument (e.g., the handle 21 of the ultrasound instrument). For example, the end effector may be an endoscope, a suture device, etc.

[0048] Return to Figure 2 Generator 25 is configured to control and supply power to the ultrasound instrument to control (e.g., heat) the end effector 23, while the instrument is coupled to the generator and used by the operator (e.g., manipulating tissue and / or performing one or more surgical tasks on the tissue during laparoscopic surgery, such as cutting and sealing blood vessels and / or cutting, grasping and dissecting tissue). Specifically, the generator may supply power to the ultrasound instrument such that the surgical system 1 (e.g., the ultrasound instrument of the surgical system) can operate in one of one or more power states (or cycles). For example, the generator may supply power to the instrument such that the ultrasound instrument is in a “high power” state (or “heating state”), where the instrument draws power (or current) from the generator (e.g., at a specific voltage) to generate heat in the end effector 23. For example, the generator may supply (e.g., a first) current (or input current) to the handle of the ultrasound instrument (e.g., a tool driver of the handle), which can use the current to drive the blade 30 to vibrate (or oscillate) within a (first) offset range (and at a specific frequency). When the blade of the end effector vibrates against an object (such as tissue) within this offset range, frictional heat can be generated by the end effector and can be used to cut and / or burn the object, as described herein.

[0049] In another embodiment, the ultrasonic instrument may be arranged to operate in a “low-power” state (or “cooling state”), wherein the ultrasonic instrument no longer draws (sufficient or equal) power from the generator, while the instrument is in a high-power state to heat the end effector. Specifically, when in this state, the generator may be configured to provide less power to the ultrasonic instrument than the power provided by the generator when the instrument is in the high-power state, such that the end effector does not generate heat (e.g., when in contact with an object). Specifically, the current (e.g., a second current) that the generator may provide to the ultrasonic instrument may be less than the (first) current provided by the generator when the instrument is operating in the high-power state, and therefore this does not cause the end effector to generate heat (or the same amount of heat as when the ultrasonic instrument is in the high-power state). Thus, once the ultrasonic instrument transitions from the high-power state to the low-power state, the ultrasonic instrument can begin to cool. Ultimately, if maintained in the low-power state, the temperature of the ultrasonic instrument can drop to (at least or below) a threshold temperature (e.g., room temperature). In one embodiment, the second current may be less than a predefined threshold current. In one embodiment, the blade can vibrate at the same frequency in a low-power state as it does in a high-power state. In another embodiment, the blade can vibrate within a tolerance frequency range.

[0050] Because of the smaller current supplied to the instrument in the low-power state, the blade of the end effector can be driven differently by the tool driver of handle 21 compared to the high-power state. Specifically, the blade can vibrate within an offset range different from the blade vibration offset when the instrument is in the high-power state. For example, when in the high-power state, the blade can vibrate within a first (e.g., high) offset range, which can cause the blade to generate heat when pressed against an object, while in the low-power state, the blade can vibrate within a second (e.g., lower) offset range, which can be smaller than the first offset (e.g., the blade shifts less along the longitudinal Y-axis compared to the first offset). In some embodiments, the second offset can be smaller than a minimum threshold (e.g., if the blade will vibrate within a minimum threshold range, the blade will generate heat at that minimum threshold). In one embodiment, the end effector may not generate frictional heat when vibrating within this lower offset range and when vibrating against an object (e.g., when the gripper squeezes the object) (such as a blood vessel). In one embodiment, the resonant frequency is maintained within tolerance, regardless of the power state in which the instrument is operated.

[0051] In one embodiment, the difference in vibration of the end effector can be based on the amount of power being drawn by the ultrasonic instrument when in different states. For example, the displacement of the blade during its oscillation can be based on the power drawn by the instrument (e.g., proportional to that power), whereby a greater amount of power drawn by the instrument causes the blade to vibrate within a higher displacement range. Conversely, when the ultrasonic instrument is in a low-power state, the instrument can draw less power, which causes the blade to vibrate less (compared to when the instrument is in a low-power state). Due to oscillation within a smaller displacement range, the blade may not generate frictional heat (e.g., when in contact with tissue). In another embodiment, the blade may generate some frictional heat when in a low-power state and in contact with an object, but this may be less than the heat generated when the instrument is in a high-power state. In this case, such generated frictional heat may be insufficient to cut and / or seal tissue. In some embodiments, due to operation in a low-power state, the end effector of the ultrasonic instrument can enter a cooling cycle, whereby the heat generated by the end effector when the instrument is in a high-power state is dissipated (e.g., for a period of time). In another embodiment, the blade may not vibrate when in this low-power state (e.g., the tool actuator may not drive the blade).

[0052] In one implementation, the system may enter (or operate in) at least one of the power states based on user input (e.g., received by generator 25). Specifically, the generator may provide power to the ultrasonic instrument based on receiving user input to one or more input devices (e.g., input to a foot pedal, a UID controlled by the operator and communicatively coupled to system 1, and / or input at the handle 21 of the ultrasonic instrument). The power provided based on the user input may place the ultrasonic instrument in a high-power state, where the ultrasonic instrument draws power from the generator to heat the end effector 23 (e.g., the blade 30 of the end effector). For example, when the generator receives (first) user input (e.g., by the operator pulling or pressing a trigger on handle 21), the generator may provide current to the ultrasonic instrument (e.g., the tool driver of the ultrasonic instrument), which uses this current to drive the end effector, as described herein. Thus, in the case where the trigger controls the articulated arm of the end effector, the generator is configured to provide current when the articulated arm is moved (e.g., moved toward the blade 30 by at least a threshold distance). In another implementation, the system may enter a low-power state based on another (e.g., a second) user input (e.g., receiving input from a different input device (such as a foot pedal) coupled to the generator).

[0053] In some embodiments, the ultrasound device can be arranged to switch between a high-power state and a low-power state. As described herein, the device can operate in a high-power state when the generator is receiving user input (e.g., the user pulls or presses a trigger on the handle). The device can operate in a low-power state in response to the generator no longer receiving user input. For example, the ultrasound device can switch from a high-power state to a low-power state in response to the user releasing the trigger on the handle (the generator can switch between these two states). In one embodiment, the device can operate in a low-power state while the operator does not actively use the device to perform ultrasound device operations, as described herein. Specifically, the system can enter a low-power state while user input is not received in one or more input devices used by the operator to enter a high-power state. However, once the operator wishes to actively use the ultrasound device, the ultrasound device can switch back to a high-power state (e.g., in response to user input). In another embodiment, the device can operate in a low-power state in response to receiving user input (e.g., the user presses a button on the UID). In yet another embodiment, the device can operate in this state for a period of time. As described herein, the surgical system is configured to determine the temperature of the end effector when in a low-power state (e.g., after switching from a high-power state) in order to inform the operator of the temperature, which may be high because the instrument has already been operated in a high-power state. Once the end effector cools to a specific temperature (e.g., equal to or less than a predefined temperature), the generator can deactivate the instrument by stopping the supply of a lower current, because at that temperature, the end effector may not cause thermal damage if it will come into contact with tissue.

[0054] In one implementation, the generator can provide different levels of current to heat the blade, based on user input. For example, the generator may receive a first user input (e.g., from a pedal coupled to the generator) and, in response, provide a maximum (permissible) amount of current to the ultrasonic instrument. The ultrasonic instrument can then drive the end effector within a maximum (e.g., predefined) offset range, which allows the end effector to generate heat at a (first) high temperature. However, when the generator receives a second user input (e.g., from another pedal coupled to the generator), the generator can provide a smaller amount of current to the ultrasonic instrument. Therefore, the ultrasonic instrument can draw less power to cause the end effector to vibrate within a (second) lower offset range, which may be lower than the first offset within which the blade vibrates in response to the first user input. However, this lower offset allows the end effector to be heated at a lower temperature compared to the first temperature of the end effector when the ultrasonic instrument draws a larger current (in response to the generator receiving the first user input). By heating the end effector to different temperatures, different types of tissue can be cut and / or cauterized. For example, tissue with more fat may require a hotter end effector (having a first temperature), while thinner (and less fat) tissue may require less heat (having a second temperature) to cut and / or cauterize the tissue. In another embodiment, the generator may be configured to provide a current when in a high-power state (e.g., to drive the end effector within a first high offset range).

[0055] As described herein, an ultrasonic instrument can be activated (e.g., operated in a high-power state) based on whether the end effector is in a closed position to grasp an object (e.g., a tissue block). For example, the ultrasonic instrument can be activated (e.g., by a user) such that it operates in a high-power state to draw sufficient current to generate heat in the end effector. Specifically, a generator can activate the ultrasonic instrument upon receiving user input to close the end effector (e.g., to move the articulated arm 31 within the distance of the blade 30). Once user input to move the articulated arm is received, the generator can be configured to provide (e.g., sufficient) power to activate the instrument, as described herein. In some embodiments, the generator can activate the instrument based on determining that the articulated arm and / or the blade is in contact with an object. For example, the ultrasonic instrument may include one or more sensors (e.g., force / pressure sensors) for detecting the presence of an object and / or detecting contact between the object and both arms. Specifically, the generator can enter a high-power state upon determining that the gripper is compressing the object (based on pressure detected from the sensors being above a threshold). Upon making this determination, the generator can provide a first current to cause the blade to oscillate in order to generate heat in the blade. Once the pressure reading drops below the threshold (meaning the object has been released by the gripper), the generator can switch to a low-power state.

[0056] In one embodiment, a surgical system (e.g., a generator for the surgical system) may be configured to determine one or more characteristics of the ultrasound instrument (its end effector) when the ultrasound instrument is in one or more power states. For example, the generator may be configured to maintain tracking (or monitoring) characteristics such as the input voltage, input current, resonant state, resonant frequency, and / or (e.g., mechanical) impedance of the ultrasound instrument (e.g., the end effector of the ultrasound instrument). In one embodiment, a “resonant frequency” may be the frequency at which an object such as an ultrasound instrument (e.g., a portion of the end effector) vibrates (e.g., naturally). In this case, the resonant frequency may be the frequency at which the end effector vibrates when the end effector is in a heated and / or cooled state. In some embodiments, the resonant frequency of the end effector may vary based on the temperature of the end effector (e.g., the blade 30 of the end effector). Further details regarding resonant frequencies are described herein. In one embodiment, the generator may be configured to monitor at least some of these characteristics of the instrument when the instrument is operating in a high-power state. Additionally, the system may be configured to determine these characteristics (at least some of them) when the instrument is in a low-power state (cooling cycle or cooling period) because the instrument draws at least some power. For example, when in a low-power state, the generator can determine the resonant frequency and impedance of an end effector (e.g., the blade 30 of the end effector). Further details on determining these characteristics are described herein.

[0057] In one embodiment, the surgical system may include additional components. For example, the system may include a cable connecting the generator to an ultrasonic instrument (e.g., an ultrasonic transducer configured to convert an electrically driven signal into mechanical vibrations). In one embodiment, the ultrasonic transducer may be connected to a waveguide that is connected to the blade 30 of the end effector 23.

[0058] As also shown in the figure, generator 25 includes a display 24, which is arranged to display information about the operation of the ultrasound instrument. For example, the display may present temperature information, the current status of the ultrasound instrument, and one or more characteristics described herein.

[0059] Figure 4This is a block diagram of a surgical system 1 according to one embodiment. The system includes an ultrasound instrument 20, a generator 25, a controller 40, a storage device (memory) 44, a display 15, and a speaker 43 (which may be a separate speaker or part of the system's electronics, such as part of a user console 2). In one embodiment, the system may include more or fewer components, such as having more than one display and / or not having a speaker. Although the components are shown as separate, at least some components may be part of each other (or integrated with each other). For example, the storage device 44 may be part of the controller 40 (e.g., as internal memory of the controller). As another example, the controller 40 may be part of the generator 25, or it may be part of a separate electronics that may be communicatively coupled to the generator 25.

[0060] Examples of storage device 44 (e.g., a non-transitory machine-readable storage medium) may include read-only memory, random access memory, CD-ROM, DVD, magnetic tape, optical data storage device, flash memory device, and phase-change memory. Storage device 44 includes one or more temperature models 45 that can be used by surgical system 1 (e.g., its controller 40) to determine (estimate) one or more temperatures of at least a portion of ultrasound instrument 20. Specifically, the temperature models may be configured to output temperature values ​​(e.g., in degrees Celsius) from the controller in response to input of one or more parameters. In one embodiment, at least some of the models 45 may represent a temperature estimate relative to a resonant frequency. In some embodiments, one or more models 45 may output a temperature in response to one or more characteristics of the ultrasound instrument, such as a resonant frequency, as input. Further information regarding the use of temperature models is described herein.

[0061] In one embodiment, one or more temperature models 45 may be predefined models, such as those determined (or created) in a controlled setting (e.g., in a laboratory) and provided to the surgical system, such as by downloading from a remote server via a network (e.g., the Internet). In one embodiment, the temperature model may be a machine learning (ML) model that can be (e.g., continuously) trained to estimate temperature based on one or more sets of training data. In one embodiment, the ML model may be any type of ML model, such as a deep neural network (DNN), a convolutional neural network (CNN), etc. As described herein, the controller 40 may use at least some of the temperature models to estimate the temperature of the end effector of the ultrasound instrument 20.

[0062] In another embodiment, the model may include different types of models based on the (current) state of the ultrasound instrument, which can be used by the surgical system to estimate the temperature of the end effector 23. For example, model 45 may include one or more cooling temperature models that can be used by the system to estimate the temperature of the end effector when the instrument is in a cooled state, and / or may include one or more heating temperature models that can be used by the system to estimate the temperature of the end effector when the instrument is in a heated state. In another embodiment, model 45 may include a model based on the state of the end effector of the ultrasound instrument. For example, model 45 may include one or more models that the system can use to estimate the temperature of the end effector when the end effector is "in the air" (e.g., not in contact with an object). Specifically, when an operator holds the ultrasound instrument 20 (e.g., the handle 21 of the ultrasound instrument), the end effector may be in the air, such that an open space completely surrounds the end effector (e.g., the blade 30 of the end effector). In one embodiment, the end effector may be in contact with one or more objects when in the air. For example, an object may (unintentionally) attach to a portion of the blade, which may be based on the temperature of the blade. In another embodiment, model 45 may include one or more models that the system can use to estimate temperature when the end effector contacts the object. In this case, the end effector can be considered to be in contact with the object when the operator manipulates the handle such that at least a portion of the end effector is pushed against the object. More information about the different models is described herein.

[0063] Storage device 44 also includes one or more model coefficients 46, which may be terms, values, and / or functions that can be used by one or more temperature models in temperature model 45 to calculate the estimated temperature. In one embodiment, the model coefficients may be based on characteristics of the ultrasound device. For example, the coefficients may include functions of characteristics (e.g., resonant frequency), such that one or more coefficients can be estimated as outputs in response to a function of one or more characteristics as input. In some embodiments, the model coefficients may be numerical. In another embodiment, the model coefficients 46 may be stored in a lookup table that associates the model coefficients with one or more characteristics. In this case, the controller may be configured to estimate the model coefficients by performing a table lookup on the data structure using one or more determined characteristics of the ultrasound device. Further details regarding the determination of coefficients are described herein.

[0064] In one embodiment, the storage device may include one or more models and / or one or more model coefficients associated with a particular device (e.g., device-specific). For example, different ultrasound instruments may have different physical properties, which may affect the rate at which temperature may rise or fall. Therefore, the storage device may include one or more models and / or model coefficients for different ultrasound instruments. For example, the storage device may include a first heating model for a first instrument and a second heating model for a second instrument.

[0065] In some embodiments, controller 40 may be a dedicated processor, such as an application-specific integrated circuit (ASIC), a general-purpose microprocessor, a field-programmable gate array (FPGA), a digital signal controller, or a set of hardware logic structures (e.g., filters, arithmetic logic units, and dedicated state machines). In one embodiment, the controller may be part of an electronic device, such as a console computer system 16, a control tower 3, and / or a user console 2. Although shown as a single component, in another embodiment, the controller may include one or more electronic components (e.g., processors, memory, etc.) communicatively coupled to a single electronic device (such as console computer system 16) or across multiple devices (e.g., communicating on a wireless computer network). In some embodiments, the controller may be part of a separate device, such as part of a remote server communicating with one or more electronic devices. In another embodiment, the controller may be part of generator 25 (e.g., at least partially integrated therein), as described herein. In this case, at least some other elements (e.g., speakers and displays) may also be part of the generator (integrated therein). Thus, at least some of the operations performed by the controller described herein may be performed by generator 25.

[0066] In one embodiment, the controller may be configured to perform a temperature estimation operation when the instrument is in one or more states, such as a cooled state (e.g., a low-power state where the blade of the end effector is not actively heated for cutting and / or sealing tissue), to allow the surgical system 1 to determine the (e.g., real-time) temperature (or temperature change) of the ultrasonic instrument (e.g., the end effector of the ultrasonic instrument). Specifically, the controller may determine the temperature based on one or more characteristics of the instrument (such as the resonant frequency of the end effector (e.g., the blade of the end effector) determined when the ultrasonic instrument is in a cooled state. The controller may use one or more temperature models 45 to determine the temperature, whereby the temperature model may output the estimated temperature of the blade as input based on the resonant frequency. For example, the controller may determine whether the end effector of the ultrasonic instrument is in a heated or cooled state, which may be based on estimated characteristics of the instrument (e.g., voltage, current, etc.). In response to determining that the system is in a heating state, the controller can estimate the temperature of the end effector based on the output of a first temperature model (e.g., a heating model), which is based on one or more characteristics, such as the resonant frequency of the instrument. In response to determining that the system is in a cooling state, the controller can estimate the temperature of the end effector based on the output of a second temperature model (e.g., a cooling model), which is based on one or more characteristics. The controller can be configured to present (e.g., display) a notification based on the estimated temperature. Therefore, the system can estimate the temperature of the end effector regardless of the state in which the instrument is operating and can display the estimated temperature to the operator (e.g., in real time). Further information regarding operations performed by the controller is described herein.

[0067] In one implementation, temperature estimation operations (at least some of these operations) may be performed by a controller when the end effector is in a heated and / or cooled state. As described herein, the temperature estimation operations may be performed during the cooled state, and when the end effector is “in the air,” this means that the blade is not in contact with an object (such as tissue) (e.g., based on operator manipulation) (and / or not at least partially immersed in a liquid). Specifically, as described herein, during laparoscopic surgery, one or more gases may be used to create a cavity within the patient’s abdomen. In this case, the temperature estimation operations may be performed when the end effector (the blade) is located within the cavity, but when the end effector (e.g., the operator holds an ultrasound instrument such that the end effector is suspended within one or more gases inside or outside the cavity.

[0068] In another embodiment, temperature estimation can be performed when the end effector of the ultrasonic instrument comes into contact with an object. In one embodiment, one or more characteristics of the ultrasonic instrument can be changed based on whether the end effector (e.g., the blade of the end effector) is in air or in contact with an object. For example, when the blade touches the object, its resonant frequency (or damped natural frequency, ω) increases due to the increase in the blade's stiffness k. d This can be increased, which is the opposite of when the knife is in the air. Specifically, the damping natural frequency can be considered as:

[0069]

[0070] Where γ is the damping ratio, and ω n It is the undamped natural frequency of the knife, which can be written as a function that depends on the stiffness of the knife:

[0071]

[0072] Where m is the mass of the blade. In one embodiment, m may include the mass of the blade and any object attached to the blade (e.g., residual tissue). The damping ratio can be written as:

[0073]

[0074] Where b is the damping on the blade. Therefore, as k increases (e.g., due to the blade touching the object), ω n Increase, therefore γ decreases, both of which make ω d Increase.

[0075] In one embodiment, at least some of the operations performed by the controller may be implemented in software (e.g., as instructions) stored in the surgical system's memory (e.g., the controller's storage and / or (internal) memory) and executed by the controller, and / or may be implemented by hardware logic structures. In one embodiment, at least some of the operations performed by the controller may be performed whenever the instrument enters a state (or switches between multiple states, such as switching between a cooling state and a heating state). In another embodiment, when the surgical system is in a particular state, the controller may periodically (e.g., per second) perform one or more of the operations described herein, such that an estimated temperature can be presented to the operator during a surgical procedure using an ultrasound instrument.

[0076] As shown in the figure, the generator can receive user input (e.g., via one or more electronic devices coupled to the generator) to cause the generator to perform one or more operations. For example, user input can be received via an ultrasound device (e.g., when the user pulls on a trigger on the handle) to cause the generator to provide current that switches the ultrasound device from a low-power state to a high-power state, as described herein.

[0077] Figures 5 to 8 and Figure 10 The flowcharts for processes 50-80 and 100 are respectively, each including one or more operations for performing temperature estimation operations, which can be executed by surgical system 1 (e.g., controller 40 and / or generator 25 of the surgical system), as described herein. Specifically, the operations described herein can be performed by an operator using an ultrasound instrument during surgical procedures. For example, at least some operations can be performed while the instrument is being used to perform a surgical task, and / or can be performed before (and / or after) the task has been performed. In another embodiment, at least some of the operations can be performed by generator 25 (e.g., by one or more processors of the generator). Therefore, these figures will refer to Figures 1 to 4 To describe. In one embodiment, at least some of these operations can be performed while the ultrasonic instrument is in one or more of the states described herein. For example, they can be performed while the ultrasonic instrument is in a heated state. Figure 6 The operation described in process 60. As another example, it can be performed separately when the ultrasonic instrument is in a cooled state. Figure 7 and Figure 8 At least some of the operations in processes 70 and 80.

[0078] Go to Figure 5 The diagram illustrates a flowchart of one embodiment of a process 50 for estimating the temperature of an end effector of an ultrasonic instrument. Specifically, this process may be (at least in part) executed by a controller 40 to determine which configuration (or state) the end effector of the ultrasonic instrument is operating in order to estimate the temperature of the end effector, and to estimate the temperature based on the determined configuration.

[0079] Process 50 begins with controller 40 determining the input current entering ultrasound instrument 20 (at block 51). For example, controller 40 may receive the input current from one or more sensors (e.g., current sensors) of surgical system 1 (e.g., its instrument 20) that monitor the current being drawn by the ultrasound instrument. In another embodiment, controller 40 may receive sensor data (e.g., characteristics) from generator 25, which may include the input current, and generator may be configured to monitor the data.

[0080] Controller 40 determines whether the ultrasound instrument is in a heated state based on the input current (at decision box 52). Specifically, the controller determines whether the end effector of the ultrasound instrument is in a heated state (e.g., being used to cut tissue) or a cooled state (e.g., being held in the air by the operator to allow the instrument to cool down after being used to perform a surgical task). Controller 40 may determine which state the instrument is in based on the current being drawn by the instrument. For example, when the ultrasound instrument is in a heating cycle, the instrument can draw a large amount of current. Specifically, as described herein, the instrument can draw more current when the end effector generates heat compared to the amount of current drawn by the instrument in a cooling cycle. In this case, the controller may be configured to determine whether the instrument is in a heated state based on whether the input current is greater than a current threshold. In one embodiment, the current threshold may be between 0.1 mA and 4 mA. If it is determined that the instrument is in a heated state (e.g., based on the input current being greater than the current threshold), controller 40 estimates the temperature of the end effector of the ultrasound instrument based on a heating model (at box 53). For example, the controller may use a heating model from model 45 stored in storage device 44 to predict the temperature of the end effector. This article describes more about estimating temperature when the instrument is in a heated state.

[0081] However, if the ultrasonic instrument is not in a heated state (e.g., based on an input current less than a current threshold), the controller can determine that the instrument is in a cooled state. Controller 40 can be configured to determine the impedance of the end effector of the ultrasonic instrument (at block 54). Specifically, the impedance can be determined when the instrument is in a cooled state. As described herein, the impedance can be mechanical impedance, which can be determined by controller 40 using one or more of the (monitored) characteristics of the ultrasonic instrument, such as the input current and / or input voltage of the end effector. For example, the controller can use the input current of the ultrasonic instrument (e.g., the blade used to drive the end effector) and the input current, and determine the mechanical impedance based on these characteristics (e.g., based on Ohm's law). In one embodiment, the input voltage can be varied to maintain a current that can be set to compensate for variations in impedance. In another embodiment, the controller can determine the impedance by applying one or more of the characteristics to an impedance model (e.g., a predefined impedance model of the output mechanical impedance, such as an electromechanical model of the impedance of at least a portion of the end effector). In another embodiment, the controller can use any known method to determine the impedance of the blade. In one embodiment, the controller can receive the impedance from generator 25.

[0082] Controller 40 determines whether the end effector is in contact with an object based on impedance (at decision box 55). Specifically, controller 40 determines whether the end effector is being cooled by air or by contact cooling. Specifically, controller 40 determines whether the end effector is in contact with an object (such as tissue) (e.g., by an operator manipulating an ultrasound instrument to bring the end effector into contact with the object) or whether it is in the air (e.g., where the ultrasound instrument is manipulated by an operator to levitate in the air and is not manipulated by the operator to make contact with the object). In one embodiment, to determine whether the end effector is in contact with an object, the controller may determine whether the impedance is greater than an impedance threshold. In response to determining that the impedance is greater than the threshold, the controller may determine that the end effector is in a cooled state while in contact with the object. The controller may be configured to estimate the temperature of the end effector of the ultrasound instrument based on a contact cooling model (at box 56). For example, when determining that the end effector is in contact with an object, the controller may be configured to determine a cooling model (e.g., from model 45) that determines that the end effector is in contact with the object, and may be configured to use the model to determine the temperature of the end effector. This article describes more about estimating the temperature of an end effector when an ultrasonic instrument is cooled and in contact with an object.

[0083] However, if the impedance is less than an impedance threshold, the controller determines that the end effector is in a cooled state and is in air. The controller estimates the temperature of the end effector of the ultrasonic instrument based on an air cooling model (at box 57). In one embodiment, the air cooling model used by the controller (which can be retrieved from model 45 in storage device 44) may differ from the contact cooling model described herein. For example, the air cooling model may be a polynomial model, while the contact cooling model may be an exponential model. Further details regarding the estimation of the temperature of the end effector when the ultrasonic instrument is in a cooled state and in air are described herein.

[0084] Therefore, the controller 40 can be configured to determine the state of the ultrasound instrument, such as whether the instrument is in a heated state, a cooled state when the end effector is in contact with the object, or a cooled state when the end effector is in the air, and can be configured to estimate the temperature based on the state of the instrument. In one embodiment, the controller can perform at least some of these operations periodically and / or continuously during instrument use, such that the controller can estimate the temperature of the end effector as the instrument switches between states to provide the operator with a real-time temperature estimate. Thus, the surgical system can effectively, efficiently, and seamlessly provide the operator with a temperature estimate as the instrument switches between states.

[0085] Figure 6This is a flowchart of one embodiment of a process for estimating the temperature of the end effector of an ultrasonic instrument when the end effector is in a heated state. Specifically, when the controller 40 determines that the ultrasonic instrument 20 is in a heated state (e.g., in...), Figure 5 At boxes 52 and 53 of process 50, at least some of the operations described in process 60 can be performed.

[0086] Process 60 begins with controller 40 determining the start temperature T of the end effector of the ultrasonic instrument. 开始 (At box 61). Specifically, the controller can determine T at the (start) time. 开始 This time can be the time when the end effector has entered (or when the controller determines that it has entered) the heating state. For example, the controller can determine (or once the controller determines that) the ultrasonic instrument is in Figure 5 When decision box 52 in process 50 is in a heating state (e.g., once the input current of the ultrasound device has exceeded the current threshold), T is determined. 开始 In one implementation, the controller can determine T by monitoring the input current of the ultrasound device to determine the time the device is in a heating state. 开始 ,like Figure 5 The process described in 50.

[0087] In one implementation, T 开始 This can be determined by the controller 40 based on the environment in which the instrument is located. Specifically, T 开始 The ambient temperature can be determined as (approximately or equal to) the environment. For example, T 开始 It can be determined based on temperature data received from a temperature sensor of the surgical system (e.g., ambient temperature). In another embodiment, T 开始 This can be based on the surgical site where the end effector is located. For example, as described herein, these operations can be performed while an ultrasound instrument is being used to perform a surgical task at a surgical site (e.g., inside a patient's abdomen) during surgery. In this case, the surgical system can... 开始 The controller determines the patient's (e.g., measured or estimated) body temperature. In one embodiment, the controller may determine the environment in which the end effector is located based on sensor data captured by one or more sensors of the surgical system. For example, the controller may be configured to perform an object recognition algorithm on video data captured by one or more cameras of the system, and when identifying the environment of the end effector (based on the object recognition algorithm), the controller may determine the temperature of the environment. For example, the controller may use the identified environment to perform a table lookup on a data structure that associates (e.g., ambient) temperature with the environment.

[0088] In another implementation, T 开始The end effector temperature can be estimated based on a previous estimate by controller 40. As described herein, the surgical system can perform the operations described herein to estimate the end effector temperature when the system switches between states (such as switching between an air-cooled state and a heated state). In this case, the controller can... 开始 The estimated temperature is the temperature estimated by the controller (e.g., the final temperature), while the system is in a previous (e.g., air-cooled) state before entering the current heating state. This article describes more about estimating the temperature when in a cooling state.

[0089] return Figure 6 The controller 40 determines the heating start (first) resonant frequency RF of the end effector of the ultrasonic instrument. HS (at box 62). In one implementation, RF HS It is with T 开始 The resonant frequency is determined by the associated start time. For example, RF. HS This could be the resonant frequency at the start time of the end effector entering (or transitioning to) another state (e.g., the time when the end effector enters a heating state). In one embodiment, T can be determined... 开始 At the same time (or with T) 开始 At the same time (for example, relative to the clock of the surgical system) (at least partially) determine RF HS .

[0090] In some implementations, the controller (and / or generator) may electronically determine the resonant frequency. For example, the generator may sense voltage and current waveforms (and the phase difference between the two waveforms) used to drive an end effector (e.g., an end-effector). Specifically, the ultrasonic instrument 20 (e.g., a tool driver) may include an ultrasonic transducer configured to vibrate the blade according to the input voltage and current waveforms. The frequency at which a phase difference is generated as a threshold (e.g., zero) is the resonant frequency. In this case, the surgical system may be configured to determine the RF using one or more characteristics. HS Such as in determining T 开始 When (or when sensing the time used to determine T) 开始 The voltage and current sensed (or measured) during the process. In another embodiment, other known methods can be used to determine the resonant frequency.

[0091] Controller 40 determines the (second) resonant frequency RF of the end effector (at block 63). In one embodiment, RF may be determined at the RF... HS The subsequent resonant frequency (e.g., relative to the clock of a surgical system) is then determined by the controller. For example, the controller can determine the RF... HS The time after the start time determines the RF. For example, RFHS The start time (e.g., T = 0 s) can be determined, which may be the time when the system enters the heating state, and RF can be determined at a later time (e.g., T = 1 s). Controller 40 determines the change ΔRF of the heating start resonant frequency. HS (At box 64). Specifically, the controller may be RF-based. HS The difference between (the first resonant frequency) and RF (the second resonant frequency) determines ΔRF. HS Such as ΔRF HS =RF HS –RF.

[0092] Controller 40 is based on ΔRF HS Determine (estimate) the temperature change ΔT (at box 65). Specifically, the controller can use a heating model to determine ΔT. For example, the temperature change could be based on ΔRF as a model input. HS The controller outputs the heating model. In one embodiment, the controller can retrieve the heating model from the temperature model 45 stored in the storage device 44. For example, the controller can perform a table lookup on the data structure including the temperature model 45 based on one or more parameters. Specifically, the controller can select the heating model associated with the ultrasonic instrument 20 from the temperature model 45. As described herein, the storage device may include device-specific models. In this case, the controller can determine an identifier associated with the ultrasonic instrument and select the temperature model associated with the identifier. In one embodiment, the selected model may be a polynomial model, such as a third-order polynomial. In another embodiment, the heating model may be a second-order polynomial model. In some embodiments, the heating model may be any type of model, such as an exponential model.

[0093] The controller is based on T 开始 The temperature T of the end effector is determined by ΔT. H (At box 66). Specifically, the controller 40 can add (combine) the temperatures to determine the temperature of the end effector, such that T H =T 开始+ΔT. Therefore, the controller estimates the temperature of the end effector based on its initial temperature, initial resonant frequency, and subsequent resonant frequency. Controller 40 presents a notification (at box 67) based on the end effector's temperature. For example, System 1 may display a pop-up notification indicating the estimated temperature on display 15. As another example, controller 40 may output an audible notification via one or more speakers (e.g., speaker 43). For example, the audible notification may be one or more sounds indicating the temperature of the end effector (e.g., a beeping sound), such as a series of sounds indicating a temperature greater than a temperature threshold. In another embodiment, the notification may be spoken words (e.g., "The instrument is 300°!"). In another embodiment, any type of notification may be presented.

[0094] As shown in the figure Figure 7 and Figure 8 It includes several operation boxes, which are included in Figure 6 In the middle (and described in relation to this figure), such as boxes 61, 63, and 67. For the sake of brevity, they will not be described again. Figure 7 and Figure 8 Description targeting Figure 6 At least some of these operation boxes are described.

[0095] Go to Figure 7 The figure illustrates a flowchart of one embodiment of a process 70 for estimating the end effector temperature of an ultrasonic instrument when the end effector is in a cooled state. In one embodiment, the controller 40 may perform at least some of the operations of process 70 when it is determined that the ultrasonic instrument is in a cooled state, such as... Figure 5 The process described in step 50. In another embodiment, the operation may be performed when the controller 40 determines that the ultrasound instrument is switching from a heating cycle to a (current) cooling cycle (e.g., when user input is no longer received via generator 25 to activate the end effector of the ultrasound instrument to perform surgical tasks such as cutting and cauterizing tissue).

[0096] Process 70 begins with controller 40 determining the start temperature T of the end effector of the ultrasonic instrument. 开始 (At box 61). For example, the controller can... 开始 Defined as the temperature estimated when the ultrasonic instrument is in a heating cycle (e.g., last) before entering the current cooling cycle. Controller 40 determines the cooling start resonant frequency RF of the end effector of the ultrasonic instrument. CS (At box 71). For example, it can be done with determining T. 开始 Same start time determines RF CS In another embodiment, RF can be determined when the controller 40 determines that the ultrasound device is in a cooling cycle (e.g., based on the ultrasound device's input current being less than or equal to a current threshold).CS .

[0097] Controller 40 determines the (e.g., subsequent) resonant frequency RF of the end effector (at box 63). The controller determines the impedance I of the end effector (at box 72). For example, the impedance can be mechanical impedance, which can be determined by controller 40 using one or more characteristics of the (monitored) properties of the ultrasonic instrument (such as input current), as described herein. Controller 40 determines the corrected resonant frequency RF based on the impedance I and the resonant frequency RF. 校正 (At box 73). Specifically, RF 校正 This can compensate for changes in one or more physical characteristics of an ultrasonic instrument that may occur during a previous heating cycle. For example, as described herein, the resonant frequency of an ultrasonic instrument may be proportional to the mass *m* of the instrument's end effector (e.g., a blade). During heating cycles using the end effector, a portion of an object (such as tissue) may inadvertently attach to a portion of the blade. Therefore, *m* may increase due to the object already attached to the blade. Consequently, when the end effector is in the air, the mass of the blade may increase due to the attachment of one or more portions of the object to the blade. As a result, the measured resonant frequency may be inaccurate. Therefore, taking into account changes in the physical characteristics of the end effector, the controller can generate RF... 校正 To compensate for RF.

[0098] In one implementation, the controller may use a resonant frequency (RF) correction model (e.g., retrieved from storage device 44) to determine the RF. 校正 In some implementations, the model can be device-specific, allowing the controller to retrieve the model using one or more characteristics (such as identifiers) of the ultrasound instrument. In this case, the controller can use the identifier to select the corresponding RF model, thereby performing a table lookup on a data structure that associates the RF calibration model with the characteristics. In some implementations, the controller can use the model to determine the adjusted resonant frequency RF. 调整 The model outputs RF in response to I, which is the model input. In one implementation, the model may be an output RF that responds to I. 调整 A (e.g., first-order) polynomial model. In another implementation, the RF correction model can be any type of model. The controller uses RF... 调整 Add to RF to determine RF 校正 This makes RF 校正 =RF+RF 调整 The controller is based on RF. 校正 Determine the change in resonant frequency ΔRF at the start of cooling CS (At box 74). Specifically, the controller may be RF-based. 校正 With RF CSThe difference between them determines ΔRF CS Such as ΔRF CS =RF 校正 –RF CS .

[0099] Controller 40 determines whether the end effector is in contact with an object (at decision box 75). For example, the controller may determine whether the end effector is in contact with an object or in the air based on whether I is greater than an impedance threshold, as described herein. If so, controller 40 determines one or more model coefficients of a contact-cooling temperature model (at box 76). Specifically, the controller may determine model coefficients and / or a contact-cooling temperature model that can be used by the controller to estimate the temperature of the end effector when it is in contact with an object and is in a cooled state. In one embodiment, the controller may determine the coefficients and model as described herein (e.g., based on the characteristics of an ultrasonic instrument) and may retrieve the coefficients and model from storage device 44.

[0100] In one implementation, the controller can use RF CS To determine the model coefficients. For example, the controller can use RF. CS Perform a table lookup on model coefficient 46 to select one or more coefficients that can be associated with the cooling start resonant frequency.

[0101] In one embodiment, the temperature model used when the end effector is in contact with an object may differ from the temperature model used when the end effector is in the air. For example, when a hot object comes into contact with a colder object, heat is transferred from the hot object to the colder object (e.g., via conduction). In one embodiment, the rate at which the object (such as end effector 23) is cooled by conduction may be faster than when the end effector is cooled by air. Therefore, the contact-cooling temperature model may be configured to achieve a faster cooling rate than the air-cooling temperature model, which the system 1 may use when the end effector is in the air. In one embodiment, to achieve the rate, the contact-cooling temperature model may be an exponential model, while the air-cooling temperature model may be a (e.g., second-order) polynomial model, where both models output a temperature change ΔT in response to an input, which may include one or more model coefficients and / or RF. CSAs described herein, in one implementation, the exponential model can have a higher ΔT relative to the same input-output ratio than the polynomial model. This may be because when in contact with another object and heat is transferred due to conduction, the end effector may cool faster (e.g., the time to drop to the threshold temperature is less than a time interval), while when heat is transferred to the air due to convection, the end effector may not cool as quickly (e.g., the time to drop to the threshold temperature is greater than that time interval). In another implementation, the two models can be of the same type. For example, both models can be polynomial models, but with different orders; for example, the contact-cooling model is a third-order polynomial (e.g., cubic) model, while the air-cooling model can be a second-order polynomial model.

[0102] Controller 40 is based on the change in resonant frequency (ΔRF) at the start of cooling. CS And model coefficients, using a contact-cooling temperature model to determine the temperature change ΔT (at box 77). For example, the controller can use ΔRF. CS And the model coefficients are input into the exponential model, such as:

[0103] ΔT=a×e b×ΔRFCS +c×e d×ΔRFCS

[0104] Where e can be an exponential constant (e.g., Euler number), and a, b, c, and d can be model coefficients. In another embodiment, the exponential model can be different, having different numbers of model coefficients. Controller 40 determines the temperature T of the end effector (at block 78) based on the start temperature and temperature changes. Specifically, T can be T0. 开始 The combination of ΔT and T makes T = T 开始 +ΔT. Controller 40 presents a notification based on the determined temperature of the end effector (at box 67).

[0105] Returning to decision box 75, if the end effector is not in contact with the object, the controller determines the model coefficients of the air-cooling temperature model (at box 79). In one embodiment, the controller 40 may determine the model coefficients based on an air-cooling temperature model. As described herein, the air-cooling temperature model may be a second-order polynomial model. In this case, the model may include three model coefficients a, b, and c. In one embodiment, the controller may be based on RF... CS Determine the model coefficients. For example, each model coefficient can be based on a function of the resonant frequency f, such as...

[0106] a = f a (RF CS )

[0107] b = f b (RFCS )

[0108] c = f c (RF CS )

[0109] Each coefficient can be obtained by using RF CS This is applied to the corresponding resonant frequency function for determination. In one implementation, to determine the model coefficients, the controller can determine their corresponding function f. a f b and f c For example, the controller may determine at least some of the functions based on one or more characteristics, such as the identifier of the ultrasound device. In particular, the functions may be device-specific, allowing them to vary between different ultrasound devices. Therefore, the controller may utilize the characteristics of the ultrasound device (such as the identifier) ​​to select the functions (e.g., by performing a table lookup on a data structure storing functions associated with the characteristics). In another embodiment, the model coefficients 46 stored in memory may include coefficients for different devices. Therefore, the controller can utilize RF... CS The coefficients are determined by performing a table lookup on a data structure that stores the model coefficients 46 in a storage device, along with one or more characteristics of the device.

[0110] Controller 40 uses an air-cooling temperature model to determine the temperature change ΔT (at box 81) based on the cooling start resonant frequency (the change) and model coefficients. For example, the controller may be based on ΔRF. CS The input is the polynomial model coefficients, and ΔT is determined as the output of the (e.g., second-order) polynomial (e.g., quadratic) model, such as:

[0111]

[0112] The controller 40 determines the end effector temperature T (at box 78) based on the start temperature and temperature changes. Specifically, T can be T0. 开始 The combination of ΔT and T makes T = T 开始 +ΔT. Controller 40 presents a notification based on the determined temperature of the end effector (at box 67).

[0113] In one implementation scheme Figure 7 Process 70 includes operations for estimating the temperature of the end effector of the ultrasonic instrument. This process can be performed using data (such as resonant frequencies) that can be collected by the ultrasonic instrument (e.g., dynamically). In another embodiment, system 1 can be configured to estimate the temperature using one or more start conditions and / or one or more end conditions of system 1. In this case, the system can estimate the temperature of any particular device without needing to collect data from the ultrasonic instrument. Figure 8 The process in which such conditions can be used to estimate temperature is described.

[0114] Go to Figure 8 This figure illustrates a flowchart of another embodiment of a process 80 for estimating the temperature of the end effector 23 of an ultrasonic instrument 20 when the end effector is in a cooled state. Specifically, process 80 includes operations for estimating the temperature of the end effector based on baseline characteristics (or start conditions) of the end effector. In one embodiment, the baseline characteristics may be characteristics specific to a particular type of ultrasonic instrument. In another embodiment, the baseline characteristics may be determined when the ultrasonic instrument is in a start condition, such as after a period of time following activation (or power insertion). Further details regarding baseline characteristics are described herein.

[0115] Process 80 begins with the controller determining the baseline resonant frequency RF of the end effector (e.g., a knife) of the ultrasonic instrument. 基线 (at box 81). In one implementation, RF 基线 This can be determined at an initial time t0, for example, when the ultrasound device 20 is coupled (e.g., inserted into) the generator 25. For instance, once the device is inserted into the generator, the controller can perform one or more diagnostic operations on the device (e.g., to determine one or more characteristics, as described herein) to determine the RF. 基线 In another implementation, the generator can be configured to determine the RF. 基线 The generator then provides the frequency to the controller 40. Therefore, based on these operations, the generator can determine the baseline frequency of the end effector's blade and provide that frequency to the controller.

[0116] In some embodiments, the baseline resonant frequency can be determined when the end effector is at (or approximately) room temperature (e.g., a temperature between 20°C and 25°C) and / or when the end effector is in the air (e.g., when the end effector's blade is not in contact with the object). In another embodiment, the baseline resonant frequency can be determined once and stored in the storage device 44 of the surgical system 1 (or the memory of the controller 40 of the surgical system). For example, the baseline frequency can be determined when the instrument is first connected to the generator, stored in the storage device 44, and retrieved by the controller if necessary. In another embodiment, the baseline frequency can be determined each time an ultrasound instrument is inserted into the generator. In another embodiment, the baseline frequency can be determined at startup of the surgical system (e.g., an ultrasound instrument) (e.g., during initial power-on). In another embodiment, the baseline frequency can be a previously determined resonant frequency (e.g., during a previous execution of process 80).

[0117] In one implementation, RF can be determined when the ultrasonic instrument is in a low-power state, the end effector is in the open position, and / or the ultrasonic instrument (e.g., the end effector and shaft of the ultrasonic instrument) is not in contact with any object. 基线 In another implementation, RF 基线 This can be determined when the ultrasonic instrument enters the cooling cycle (e.g., each time).

[0118] Controller 40 determines the baseline temperature T of the end effector. 基线 (At box 82). In one embodiment, the baseline temperature can be (or approximately) room temperature. In another embodiment, T 基线 This can be the temperature measured by a temperature sensor from a surgical system. For example, T 基线 This could be the temperature of the end effector after a period of time within the environment. In another embodiment, T 基线 This could be the temperature of the end effector measured after the end effector has been in a cooled state for a period of time. In some implementations, T 基线 It can be a predefined temperature.

[0119] In one implementation, the operations described in boxes 81 and / or 82 can be performed at any time. Specifically, the operations can be performed before the ultrasound instrument enters its current cooling state.

[0120] Controller 40 determines the start-up temperature T of the end effector of the ultrasonic instrument. 开始 (At box 61). Controller 40 determines the cooling start resonant frequency RF of the end effector. CS (At box 71). Controller 40 determines the resonant frequency RF of the end effector (at box 63) and the impedance I of the end effector (at box 72). Controller 40 determines the corrected resonant frequency RF based on I and RF. 校正 As described herein (at box 73), the controller determines whether the end effector is in contact with the object (at decision box 75).

[0121] In response to determining that the end effector is not in contact with an object (e.g., in the air), the controller 40 based on T 开始 RF CS RF 基线 and / or T 基线 Determine the model coefficients for the air-cooled temperature model (at box 85). As described herein, the end effector temperature follows a polynomial curve, such that the temperature can be defined as a polynomial function of the following:

[0122] T = a × RF 2 +b×RF+c

[0123] In this case, the model coefficients can be determined based on the initial and final conditions of the end effector. Specifically, the initial condition can be the starting temperature relative to the cooling start resonant frequency, which can be defined as:

[0124]

[0125] Termination conditions may include baseline conditions for the end effector (e.g., when the end effector is cooled to a threshold temperature such as room temperature), which may be a baseline temperature relative to the baseline resonant frequency, and this baseline temperature may be defined as:

[0126]

[0127] Furthermore, since the model is a second-order polynomial, and the slope can be zero at the end of cooling, T can be taken as the termination condition. 基线 The derivative of a function, thus producing a first-order polynomial, such as:

[0128] 0 = 2 × a × RF 基线 +b

[0129] Specifically, since the model converges to the baseline temperature (e.g., it can converge asymptotically), the model's derivative can be zero. Knowing the initial and termination conditions, the polynomial equations can be added to a 3x3 polynomial matrix, which, multiplied by the model coefficient matrix (extracted from the polynomial equations), equals the temperature matrix, as shown below:

[0130]

[0131] Since the start temperature and baseline temperature, as well as the initial resonant frequency and baseline resonant frequency, are known, controller 40 can solve for each model coefficient according to the matrix equation. Specifically, the model coefficients of the coefficient matrix can be determined by multiplying each side by an inverse 3x3 polynomial matrix. In one embodiment, the controller can determine the model coefficients by performing a table lookup on a data structure of model coefficients 46 using the known temperature and resonant frequency. In one embodiment, the model coefficients determined based on the initial and final conditions can be device-specific. In another embodiment, the coefficients may not be device-specific.

[0132] The controller 40 determines the temperature (at box 86) using an air-cooling temperature model based on the (corrected) resonant frequency and determined model coefficients. Specifically, the (e.g., current) temperature T of the end effector can be defined as...

[0133]

[0134] As described herein, the model coefficients used can be determined from the matrix equations using initial and / or termination conditions. The controller presents notifications based on the temperature of the end effector (in box 67).

[0135] Returning to decision box 75, if the end effector is in contact with the object, controller 40 based on T... 开始 RF CS RF 基线 and / or T 基线 Determine the model coefficients for the contact-cooling temperature model (at box 83). As described herein, the contact-cooling temperature model enables the end effector to cool more rapidly upon contact with an object compared to in air. Therefore, the end effector temperature follows a third-order polynomial curve, allowing the end effector temperature to be defined as the following function:

[0136] T = a × RF 3 +b×RF 2 +c×RF+d

[0137] The contact-cooling model may include four coefficients a, b, c, and d. In this case, the model coefficients can be determined based on the initial and final conditions of the end effector. Specifically, the initial condition can be the starting temperature relative to the cooling initiation resonant frequency, which can be defined as:

[0138]

[0139] The termination condition can be a baseline condition, which can be defined as:

[0140]

[0141] Furthermore, since the slope at the end of cooling can be zero, T can be taken as the termination condition. 基线 The first and second derivatives are used to obtain the following results:

[0142]

[0143] and

[0144] 0 = 6 × a × RF 基线 +2×b

[0145] Knowing the initial and termination conditions, the polynomial equation can be added to the polynomial matrix, which, multiplied by the model coefficient matrix, equals the temperature matrix, as shown below:

[0146]

[0147] Controller 40 can be configured to solve for each of the four model coefficients by multiplying each side of the matrix equation by the inverse 4x4 polynomial matrix, as described herein. Controller 40 determines the temperature (at box 84) using a contact-cooling temperature model based on the (corrected) resonant frequency and the determined four model coefficients. Specifically, the temperature T of the end effector can be defined as:

[0148]

[0149] The model coefficients a, b, c, and d used can be determined from matrix equations, as described herein. Then, controller 40 can present a notification based on the temperature of the end effector, at box 67.

[0150] Figure 9 Several stages of a display of a surgical system are shown, illustrating actions performed by an end effector of an ultrasound instrument and displaying the temperature of the end effector. Specifically, each of the four stages 90 to 93 shows a display 15 showing endoscopic video 94 (captured by an endoscope during surgery) showing the end effector 23 and shaft 22 of the ultrasound instrument at a surgical site (e.g., inside the patient's abdomen) and a portion of an object 95 (e.g., tissue, such as a blood vessel). Each stage also shows a notification 96 superimposed (overlayed) on top of a portion of the endoscopic video 94. The notification 96 includes information about the status and temperature of the end effector. In one embodiment, the status and / or temperature may be determined by the surgical system based on at least some of the temperature estimation operations described herein. In one embodiment, the display showing the endoscopic video may be a different display of the surgical system, such as display 24 of generator 25. In some implementations, the display may show other content, such as other video content and / or the graphical user interface (GUI) of the surgical system, which is displaying one or more UI items (e.g., UI items related to the surgical procedures being performed by the system operator).

[0151] The first stage 90 illustrates the end effector gripping a portion of tissue for cutting. During this stage, with the articulated arm 31 in the closed position, the ultrasonic instrument may be in or entering a heating cycle, thereby compressing the tissue between the arm 31 and the blade. Therefore, as described herein, when in the closed position and in a heating cycle, the blade can use frictional heat generated by the blade's oscillations to cut the tissue.

[0152] Additionally, the surgical system can be configured to perform temperature estimation operations to determine the operational status of the end effector and estimate its temperature. Specifically, the surgical system 1 (e.g., its controller 40) can perform at least some of the operations described herein to determine whether the ultrasound instrument is in a heating cycle. For example, the system can determine whether the input current entering the ultrasound instrument is greater than (or equal to) an input current threshold, such as... Figure 5 The process described in step 50. When the input current is determined to be greater than the threshold, the system can use a heating model to estimate the temperature, such as... Figure 6 The process described in step 60. As shown, the system presents a notification 96 (e.g., a pop-up) indicating the estimated temperature. Specifically, notification 96 indicates that the system is in a heating cycle and the temperature is 300°.

[0153] The second stage 91 shows the result of the end effector 23 cutting tissue 95. Specifically, this stage shows that the tissue has been cut into two pieces. Additionally, the ultrasound instrument is in a cooling cycle, with the articulated arm in the open position and exposed to air. Therefore, in this stage, the surgical system can be configured to determine that the ultrasound instrument has transitioned from a heated state to a cooled state based on changes in one or more characteristics. For example, the system can determine that the input current has dropped below an input current threshold, such as... Figure 5 As described above. In response, the system can estimate the temperature of the end effector based on a cooling model. Specifically, the system can determine whether the end effector 23 is in air based on characteristics such as the impedance of the end effector, and can perform temperature estimation using an air-cooling temperature model, such as... Figure 7 and / or Figure 8 The stage described above. This stage displays the result of the temperature estimate when the end effector is in the air by changing notification 96 to indicate that the end effector is now cooling and the temperature is 290°.

[0154] The third stage 92 shows that the end effector 23 has moved upward to allow it to continue cooling in the air. In one embodiment, the surgical system can continue to perform temperature estimation operations to dynamically update the temperature of the end effector (in real time). As a result, notification 96 indicates that the temperature has dropped from 290° to 238°.

[0155] Phase 93 shows that the blade 30 of the end effector 23 has moved and is now touching tissue 95. This phase also shows a notification 97 indicating "End effector contact" displayed on the display 15 to inform the operator that the end effector (the blade) is touching the object. As described herein, the surgical system 1 can be configured to determine whether the end effector is in contact with the object or in the air based on the impedance of the end effector. Specifically, when the impedance is determined to be greater than (or equal to) an impedance threshold, the surgical system can switch from estimating the temperature using an air-cooling model (from phase 92) to estimating the temperature using a contact-cooling model, such as... Figure 7 and Figure 8 As stated in either (or both) of the above. As a result of the estimated temperature, update notification 96 indicates that the temperature is now 108°.

[0156] Therefore, this figure illustrates how the controller 40 can (e.g., continuously) perform at least some of the operations of the process described herein to continuously monitor and update the status and temperature of the instrument to the operator.

[0157] Figure 10 This is a flowchart of another embodiment of a process 100 for estimating the temperature of an end effector of an ultrasonic instrument. Process 100 begins with controller 40 receiving the resonant frequency of the end effector of the ultrasonic instrument (at block 101). For example, the resonant frequency could be the initial resonant frequency. The controller determines whether the end effector of the ultrasonic instrument is in a heated or cooled state (at block 102). As described herein, the controller may determine the state of the ultrasonic instrument based on one or more characteristics, such as the instrument's input current and / or impedance. In response to determining that the end effector is in a heated state, the controller estimates the temperature of the end effector based on the output of a first temperature model (e.g., a heating model described herein), which has an input based on the resonant frequency of the end effector (at block 103). However, in response to determining that the end effector is in a cooled state, the controller estimates the temperature of the end effector based on the output of a second temperature model (e.g., an air-cooled model or a contact-cooled model), which has an input based on the resonant frequency (at block 104). The controller presents a notification based on the estimated temperature (at block 105).

[0158] Some embodiments may perform variations of at least some of the processes described herein. For example, specific operations of at least some processes may not be performed in the exact order shown and described. Specific operations may not be performed in a series of consecutive operations, and different specific operations may be performed in different embodiments. For example, the operation within the dashed box may be an optional operation that may not be performed during (or each time) the corresponding process is performed. In another embodiment, one or more operations with solid-line boundaries may be optional. In one embodiment, at least some of the operations described herein (e.g., at least some of the operations performed in one or more processes described herein) may be performed automatically (e.g., without user intervention). For example, at least some operations may be performed at any stage during a surgical procedure in which the ultrasound instrument is being used by the operator. In some embodiments, at least some of the operations described herein may be performed in real time (e.g., continuously) (e.g., when ultrasound is used during a surgical procedure), and / or at least some operations may be performed during the surgical procedure, prior to use.

[0159] As described herein, surgical system 1 can be configured to perform temperature estimation operations based on one or more defined characteristics of an ultrasound instrument, such as resonant frequency. In one embodiment, the characteristic used by the surgical system may be an average value over a time period. For example, in Figure 6 The second resonant frequency RF determined at box 63 in process 60 can be the average resonant frequency over a time period (e.g., ten seconds).

[0160] As described herein, the controller may estimate and display the temperature of the end effector. In one embodiment, the temperature of the end effector (or an indication of temperature) may be displayed as a separate notification (or within the same notification) from a notification indicating the status of the end effector. In another embodiment, the notification presented by the controller may include other information, such as whether the end effector is in contact with an object or in the air.

[0161] In some implementations, when the ultrasound device switches from a heating cycle to a cooling cycle, the controller may update the baseline resonant frequency and / or baseline temperature, and / or vice versa. Specifically, the controller may determine that the ultrasound device is in a heating cycle (e.g., the end effector is in a closed position), and in response to determining that the ultrasound device has returned to a cooling cycle (e.g., the end effector is now in an open position and / or in the air), the controller may (e.g., begin) monitor the resonant frequency of the end effector over a period of time to determine a new baseline resonant frequency.

[0162] As previously described, one embodiment of this disclosure may be a non-transitory machine-readable medium (such as a microelectronic memory) having instructions stored thereon that program one or more data processing components (collectively referred to herein as a "processor") to (automatically) perform ultrasonic instrument operations and / or temperature estimation operations, as described herein. In other embodiments, some of these operations may be performed by specific hardware components containing hard-wired logic. These operations may also be performed by any combination of programmed data processing components and fixed hard-wired circuit components.

[0163] In order to help the Patent Office and any reader of any patent published in this application interpret the claims appended herein, the applicant wishes to note that unless the words “component for…” or “step for…” are explicitly used in a particular claim, the applicant does not expect any appended claim or claim element to invoke 35 U.SC112(f).

[0164] While certain embodiments have been described and illustrated in the accompanying drawings, it should be understood that such embodiments are merely illustrative and not limiting of this disclosure, and that this disclosure is not limited to the specific constructions and arrangements shown and described, as various other modifications will be apparent to those skilled in the art. Therefore, this specification should be considered illustrative rather than restrictive.

[0165] In some embodiments, this disclosure may include language such as, “at least one of [component A] and [component B]”. This language may refer to one or more of the components. For example, “at least one of A and B” may refer to “A”, “B”, or “A and B”. Specifically, “at least one of A and B” may refer to “at least one of A and at least one of B” or “at least one of A or B”. In some embodiments, this disclosure may include language such as, “[component A], [component B] and / or [component C]”. This language may refer to any one of these components or any combination thereof. For example, “A, B and / or C” may refer to “A”, “B”, “C”, “A and B”, “A and C”, “B and C”, or “A, B and C”.

Claims

1. A method, the method comprising: Determine the resonant frequency of the end effector of the ultrasonic instrument; Determine whether the end effector of the ultrasonic instrument is in a heated or cooled state; In response to determining that the end effector is in the heated state, the temperature of the end effector is estimated based on the output of a first temperature model, the first temperature model having an input based on the resonant frequency; In response to determining that the end effector is in the cooled state, the temperature of the end effector is estimated based on the output of a second temperature model having an input based on the resonant frequency; as well as The notification is presented based on the estimated temperature.

2. The method of claim 1, wherein the resonant frequency is a first resonant frequency at the start time of the end effector entering the heating state or the cooling state, wherein the method further comprises: Determine the start temperature of the end effector at the start time; as well as Determine the second resonant frequency of the end effector of the ultrasonic instrument at a time after the start time. The temperature is estimated based on the starting temperature, the first resonant frequency, and the second frequency.

3. The method of claim 2, wherein estimating the temperature in response to determining that the end effector is in the heated state comprises: The temperature change of the end effector is determined based on the difference between the first resonant frequency and the second resonant frequency; as well as Combine the temperature change with the starting temperature.

4. The method of claim 1, wherein estimating the temperature in response to determining that the end effector is in the cooled state comprises: Determine whether the end effector is being cooled by air or by contact cooling; In response to determining that the end effector is being cooled by air, the temperature of the end effector is estimated based on the output of a first cooling temperature model; as well as In response to determining that the end effector is being contact-cooled, the temperature of the end effector is estimated based on the output of a second cooling temperature model.

5. The method of claim 4, wherein the first cooling temperature model is a polynomial model and the second cooling temperature model is an exponential model.

6. The method of claim 1, wherein the resonant frequency is a first resonant frequency, and wherein estimating the temperature of the end effector based on the output of the second temperature model comprises: The model coefficients of the second temperature model are determined based on the first resonant frequency; Determine the second resonant frequency of the end effector of the ultrasonic instrument; as well as The temperature is determined by applying the second resonant frequency and the coefficient to the second temperature model.

7. The method of claim 6, further comprising: The impedance of the end effector is determined based on the input current of the ultrasonic instrument; as well as The corrected resonant frequency is determined based on the impedance and the second resonant frequency. Determining the temperature of the end effector based on the output of the second temperature model includes applying the corrected resonant frequency as input to the second temperature model.

8. The method of claim 1, further comprising determining the input current being supplied to the ultrasonic instrument, wherein determining whether the end effector is in a heated or cooled state includes: When the input current is greater than the current threshold, the end effector is determined to be in the heating state; as well as When the input current is less than the current threshold, the end effector is determined to be in the cooling state.

9. The method according to claim 8, further comprising: The impedance of the end effector is determined based on the input current; In response to determining that the impedance is less than a threshold, it is determined that the end effector is in the cooled state when it is in air; as well as In response to determining that the impedance is greater than the threshold, it is determined that the end effector is in the cooled state when in contact with the object.

10. A surgical system, the surgical system comprising: An ultrasonic instrument, the ultrasonic instrument having an end effector; monitor; processor; and The memory has instructions that, when executed by the processor, cause the surgical system to: Determine the resonant frequency of the end effector; Determine whether the end effector is in a heated or cooled state; In response to determining that the end effector is in the heated state, the temperature of the end effector is estimated based on the output of a first temperature model, the first temperature model having an input based on the resonant frequency; In response to determining that the end effector is in the cooled state, the temperature of the end effector is estimated based on the output of a second temperature model having an input based on the resonant frequency; as well as The display shows a notification including the estimated temperature.

11. The surgical system of claim 10, wherein the resonant frequency is a first resonant frequency at the start time of the end effector entering the heating state or the cooling state, wherein the memory has additional instructions for: Determine the start temperature of the end effector at the start time; and Determine the second resonant frequency of the end effector at a time after the start time. The temperature is estimated based on the starting temperature, the first resonant frequency, and the second frequency.

12. The surgical system of claim 11, wherein the instruction for estimating the temperature in response to determining that the end effector is in the heated state includes instructions for: The temperature change of the end effector is determined based on the difference between the first resonant frequency and the second frequency; and Combine the temperature change with the starting temperature.

13. The surgical system of claim 10, wherein the instruction to estimate the temperature in response to determining that the end effector is in the cooled state includes instructions for: Determine whether the end effector is being cooled by air or by contact cooling; In response to determining that the end effector is being cooled by air, the temperature of the end effector is estimated based on the output of a first cooling temperature model; as well as In response to determining that the end effector is being contact-cooled, the temperature of the end effector is estimated based on the output of a second cooling temperature model, wherein the first cooling temperature model is a polynomial model and the second cooling temperature model is an exponential model.

14. The surgical system of claim 10, wherein the resonant frequency is a first resonant frequency, and wherein the instructions for estimating the temperature of the end effector based on the output of the second temperature model include instructions for: The model coefficients of the second temperature model are determined based on the first resonant frequency; Determine the second resonant frequency of the end effector of the ultrasonic instrument; and The temperature is determined by applying the second resonant frequency and the coefficient to the second temperature model.

15. The surgical system of claim 14, wherein the memory has additional instructions for: The impedance of the end effector is determined based on the input current of the ultrasonic instrument; and The corrected resonant frequency is determined based on the impedance and the second resonant frequency. The instruction to determine the temperature of the end effector based on the output of the second temperature model includes an instruction to apply the corrected resonant frequency as input to the second temperature model.

16. A non-transitory machine-readable medium having instructions that, when executed by a processor of a surgical system, cause the surgical system to: Determine the resonant frequency of the end effector of the ultrasonic instrument; Determine whether the end effector of the ultrasonic instrument is in a heated or cooled state; In response to determining that the end effector is in the heated state, the temperature of the end effector is estimated based on the output of a first temperature model, the first temperature model having an input based on the resonant frequency; In response to determining that the end effector is in the cooled state, the temperature of the end effector is estimated based on the output of a second temperature model having an input based on the resonant frequency; as well as The notification is presented based on the estimated temperature.

17. The non-transient machine-readable medium of claim 16, wherein the resonant frequency is a first resonant frequency at the start time of the end effector entering the heating state or the cooling state, wherein the non-transient machine-readable medium has additional instructions for: Determine the start temperature of the end effector at the start time; and Determine the second resonant frequency of the end effector of the ultrasonic instrument at a time after the start time. The temperature is estimated based on the starting temperature, the first resonant frequency, and the second frequency.

18. The non-transient machine-readable medium of claim 17, wherein the instruction to estimate the temperature in response to determining that the end effector is in the heated state includes instructions for: The temperature change of the end effector is determined based on the difference between the first resonant frequency and the second frequency; and Combine the temperature change with the starting temperature.

19. The non-transient machine-readable medium of claim 16, wherein the instruction for estimating the temperature in response to determining that the end effector is in the cooled state comprises instructions for: Determine whether the end effector is being cooled by air or by contact cooling; In response to determining that the end effector is being cooled by air, the temperature of the end effector is estimated based on the output of a first cooling temperature model; as well as In response to determining that the end effector is being contact-cooled, the temperature of the end effector is estimated based on the output of a second cooling temperature model.

20. The non-transient machine-readable medium of claim 16, wherein the resonant frequency is a first resonant frequency, and wherein the instructions for estimating the temperature of the end effector based on the output of the second temperature model include instructions for: The model coefficients of the second temperature model are determined based on the first resonant frequency; Determine the second resonant frequency of the end effector of the ultrasonic instrument; and The temperature is determined by applying the second resonant frequency and the coefficient to the second temperature model.

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