Tissue sensing circuit for a surgical instrument

Abstract

The surgical instrument includes an end effector having first and second jaws that cooperate to clamp the patient's biological material and a first electrode that delivers an electrical signal to the biological material. The instrument further includes a second electrode that receives the electrical signal from the first electrode and an electrical circuit housed within the end effector. The electrical circuit includes a microcontroller that controls delivery of the electrical signal to the first electrode, the electrical signal passing through the biological material to the second electrode. The electrical circuit also determines the electrical impedance of the biological material to determine at least one of the presence or absence of tissue in the biological material or a characteristic of the tissue in the biological material.

Description

[Background technology]

[0001] In some surgical situations, endoscopic surgical instruments may be preferred over traditional open surgical devices due to the use of smaller incisions within the patient's body, which can reduce postoperative recovery time and complications. Some endoscopic surgical instruments may be suitable for positioning a distal end effector at a desired surgical site through a trocar cannula. These distal end effectors can engage tissue in several ways to achieve diagnostic or therapeutic effects (e.g., endocutters, graspers, cutters, staplers, clip appliers, access devices, drug / gene therapy delivery devices, and energy delivery devices using ultrasound, RF, or lasers). Endoscopic surgical instruments may include a shaft between the end effector and a handle portion that is manipulated by the clinician. Such a shaft can facilitate insertion to a desired depth and rotation about the shaft's longitudinal axis, thereby facilitating positioning of the end effector within the patient's body. Positioning of the end effector can be further facilitated by including one or more articulation joints or features that allow the end effector to be selectively articulated or otherwise deflected relative to the longitudinal axis of the shaft.

[0002] Examples of endoscopic surgical instruments include surgical staplers, some of which are operable to clamp tissue layers, cut the clamped tissue layers, and drive staples through the tissue layers to substantially seal the cut tissue layers together near the cut ends of the tissue layers. Merely exemplary surgical staplers are disclosed in U.S. Pat. No. 7,380,696, entitled "Articulating Surgical Stapling Instrument Incorporating a Two-Piece E-Beam Firing Mechanism," issued June 3, 2008; U.S. Pat. No. 8,408,439, entitled "Surgical Stapling Instrument with An Articulatable End Effector," issued April 2, 2013; U.S. Pat. No. 8,453,914, entitled "Motor-Driven Surgical Cutting Instrument with Electric Actuator Directional Control Assembly," issued June 4, 2013; and U.S. Pat. No. 11,241,269, entitled "Surgical Devices Switchable Between Monopolar Functionality and Bipolar Functionality," issued February 8, 2022. The disclosures of each of the above-cited U.S. patents and U.S. patent application publications are incorporated herein by reference.

[0003] Other endoscopic surgical instruments may have an element for cutting tissue and one or more elements for transmitting energy to tissue (e.g., to coagulate or seal tissue). One example of such an electrosurgical instrument is the ENSEAL® tissue sealing device by Ethicon Endo-Surgery, Inc. (Cincinnati, Ohio).Further examples of such devices and related concepts are described in U.S. Pat. No. 6,500,176, entitled "Electrosurgical Systems and Techniques for Sealing Tissue," issued December 31, 2002, the disclosure of which is incorporated herein by reference in its entirety; U.S. Pat. No. 8,939,974, entitled "Surgical Instrument Comprising First and Second Drive Systems Actuatable by a Common Trigger Mechanism," issued January 27, 2015, the disclosure of which is incorporated herein by reference in its entirety; U.S. Pat. No. 8,888,809, entitled "Surgical Instrument with Jaw Member," issued November 18, 2014, the disclosure of which is incorporated herein by reference in its entirety; and U.S. Pat. No. 8,888,809, entitled "Motor Driven Electrosurgical Device with Mechanical and Electrical No. 9,877,720, issued January 30, 2018, entitled "Control Features for Articulating Surgical Device," the disclosure of which is incorporated herein by reference in its entirety; U.S. Pat. No. 9,545,253, issued January 17, 2017, entitled "Surgical Instrument with Contained Dual Helix Actuator Assembly," the disclosure of which is incorporated herein by reference in its entirety; and U.S. Pat. No. 9,526,565, issued December 27, 2016, entitled "Electrosurgical Devices," the disclosure of which is incorporated herein by reference in its entirety.

[0004] While many different surgical instruments have been made and used, it is believed that no one prior to the present inventors has made or used the present invention as set forth in the appended claims. [Brief explanation of the drawings]

[0005] While this specification concludes with claims particularly pointing out and distinctly claiming the present technology, the present technology will be better understood from the following description of certain specific embodiments read in conjunction with the accompanying drawings, in which like reference numerals identify the same elements. [Figure 1] FIG. 1 is a perspective view of an exemplary articulating surgical stapling instrument. [Figure 2] 2 depicts a side view of the device of FIG. 1; [Figure 3] 2 depicts a perspective view of an open end effector of the instrument of FIG. 1; [Figure 4A] 4 illustrates a cross-sectional view of the end effector of FIG. 3 taken along line 4-4 of FIG. 3 with the firing beam of the end effector in a proximal position. [Figure 4B] 4 illustrates a cross-sectional view of the end effector of FIG. 3 taken along line 4-4 of FIG. 3 with the firing beam in a distal position. [Figure 5] 5 depicts a cross-sectional end view of the end effector of FIG. 3 taken along line 5-5 of FIG. 3. [Figure 6] 4 depicts an exploded perspective view of the end effector of FIG. 3; [Figure 7] 4 depicts a perspective view of the end effector of FIG. 3 after being positioned in tissue and actuated once within the tissue to activate upon contact with the tissue. [Figure 8] FIG. 2 illustrates a top view of another exemplary end effector jaw having an electrode array configured for use with the surgical stapling instrument of FIG. 1; [Figure 9] FIG. 2 shows a perspective view of another exemplary end effector having an electrode array configured for use with the surgical stapling instrument of FIG. 1; [Figure 10A] 10 illustrates a top view of a portion of another exemplary end effector having an electrode array configured for use with the surgical stapling instrument of FIG. 1. [Figure 10B]FIG. 10B illustrates a perspective view of a staple cartridge configured for use with the end effector portion of FIG. 10A; [Figure 10C] 10B shows a side view of another exemplary end effector incorporating the end effector portion of FIG. 10A and the staple cartridge of FIG. 10B. [Figure 11A] FIG. 2 illustrates a top view of another exemplary end effector having an electrode array configured for use with the surgical stapling instrument of FIG. 1; [Figure 11B] FIG. 2 illustrates a top view of another exemplary end effector having an electrode array configured for use with the surgical stapling instrument of FIG. 1; [Figure 12] FIG. 2 shows a perspective view of an exemplary wireless end effector having an electrode array configured for use with the surgical stapling instrument of FIG. 1; [Figure 13] FIG. 2 shows a partial perspective view of another exemplary end effector having an electrode array configured for use with the surgical stapling instrument of FIG. 1; [Figure 14] 2 shows a schematic diagram of an exemplary microcontroller configured for use with the surgical stapling instrument of FIG. 1; [Figure 15A] 2 illustrates a perspective view of an exemplary end effector jaw having a microcontroller and configured for use with the surgical stapling instrument of FIG. 1; FIG. [Figure 15B] FIG. 2 illustrates a perspective view of an exemplary staple cartridge having a microcontroller and configured for use with the surgical stapling instrument of FIG. 1; [Figure 16] 1 shows a schematic diagram of an exemplary impedance triangle. [Figure 17] 2 shows a schematic diagram of a set of exemplary waveforms produced and measured by the surgical stapling instrument of FIG. 1; [Figure 18] 10 shows a flowchart of an exemplary process for utilizing tissue sensing circuitry to determine the presence and type of tissue placed in contact with an electrode.

[0006] The drawings are not intended to be limiting in any manner, and it is contemplated that various embodiments of the technology may be embodied in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several aspects of the technology and, together with the description, serve to explain the principles of the technology, although it is understood that the technology is not limited to the precise arrangements shown. DETAILED DESCRIPTION OF THE INVENTION

[0007] The following description of certain examples of the present technology should not be used for the purpose of limiting its scope. Other examples, features, aspects, embodiments, and advantages of the present technology will become apparent to those skilled in the art from the following description, which is, by way of example, one of the best modes contemplated for carrying out the present technology. As will be understood, the technology described herein is capable of other different and obvious modes, all without departing from the technology. Therefore, the drawings and descriptions should be regarded as illustrative in nature, and not as restrictive.

[0008] It should be further understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein may be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described herein. Therefore, the teachings, expressions, embodiments, examples, etc. described below should not be considered in isolation from one another. Various suitable ways in which the teachings herein may be combined will be readily apparent to those skilled in the art in light of the teachings herein. Such modifications and variations are intended to be within the scope of the claims.

[0009] For clarity of this disclosure, the terms "proximal" and "distal" are defined herein relative to a surgeon or other operator grasping a surgical instrument having a distal surgical end effector. The term "proximal" refers to the location of an element closer to the surgeon or other operator, and the term "distal" refers to the location of an element closer to the surgical end effector of the surgical instrument and further away from the surgeon or other operator.

[0010] I. Exemplary Surgical Stapler 1-7 illustrate an example of a surgical stapling and severing instrument 10 sized for insertion through a trocar cannula, thoracotomy, or other incision in a non-articulated state as shown in FIG. 1 to a surgical site in a patient to perform a surgical procedure. The instrument 10 in this example includes a handle portion 20 connected to a shaft 22. The shaft 22 terminates distally in an articulation joint 11, which is further coupled to an end effector 12. It should be understood that the terms "proximal" and "distal" are used herein with reference to a clinician grasping the handle portion 20 of the instrument 10. Thus, the end effector 12 is distal to the more proximal handle portion 20.

[0011] Once the articulation joint (11) and end effector (12) are inserted into the patient, the articulation joint (11) can be remotely articulated by the articulation control (13), as depicted in phantom in FIG. 1, so that the end effector (12) can be deflected to a desired angle (α) from the longitudinal axis (LA) of the shaft (22). By way of example only, articulation joint 11 and / or articulation control 13 may be constructed and operative in accordance with at least part of the teachings of U.S. Patent No. 9,186,142, entitled "Surgical Instrument End Effector Articulation Drive with Pinion and Opposing Racks," issued November 17, 2015, the disclosure of which is incorporated herein by reference in its entirety, and / or U.S. Patent No. 9,795,379, entitled "Surgical Instrument with Multi-Diameter Shaft," issued October 24, 2017, the disclosure of which is incorporated herein by reference in its entirety. Other suitable forms that articulation joint 11 and articulation control 13 may take will be apparent to those skilled in the art in view of the teachings herein.

[0012] The end effector 12 of this example includes a lower jaw 16 and an upper jaw in the form of a pivotable anvil 18. By way of example only, the lower jaw 16 may be constructed and operative in accordance with at least some of the teachings of U.S. Pat. No. 9,808,248, issued November 7, 2017, entitled "Installation Features for Surgical Instrument End Effector Cartridge," the disclosure of which is incorporated herein by reference in its entirety. The anvil 18 may be constructed and operative in accordance with at least some of the teachings of U.S. Pat. No. 10,092,292, issued October 9, 2018, entitled "Staple Forming Features for Surgical Stapling Instrument," the disclosure of which is incorporated herein by reference in its entirety. Other suitable forms that the lower jaw 16 and anvil 18 may take will be apparent to those skilled in the art in view of the teachings herein.

[0013] The handle portion (20) includes a pistol grip (24) and a closure trigger (26). The closure trigger (26) is pivotable toward the pistol grip (24) to cause clamping or closure of the anvil (18) toward the lower jaw (16) of the end effector (12). Such closure of the anvil (18) is effected via a closure tube (32) and a closure ring (33), both of which translate longitudinally relative to the handle portion (20) in response to pivoting of the closure trigger (26) relative to the pistol grip (24). The closure tube (32) extends along the length of the shaft (22), and the closure ring (33) is positioned distal to the articulation joint (11). The articulation joint (11) is operable to transfer longitudinal movement from the closure tube (32) to the closure ring (33).

[0014] The handle portion (20) also includes a firing trigger (28). An elongate member (not shown) extends longitudinally through the shaft (22) and, in response to actuation of the firing trigger (28), transmits longitudinal firing motion from the handle portion (20) to the firing beam (14), for example, via a motor (140) (not shown) housed within the handle portion (20). As described in further detail below, this distal translation of the firing beam (14) effects stapling and severing of tissue clamped within the end effector (12). The triggers (26, 28) can then be released, releasing the tissue from the end effector (12).

[0015] As seen in FIGS. 4A and 4B , the firing beam 14 of this embodiment includes a transversely oriented upper pin 38, a firing beam cap 44, a transversely oriented middle pin 46, and a distally presented cutting edge 48. The upper pin 38 is positioned within a longitudinal anvil slot 42 of the anvil 18 and is translatable within the longitudinal anvil slot 42. The firing beam cap 44 slidably engages the underside of the lower jaw 16 by having the firing beam 14 extend through a lower jaw slot 45 (shown in FIG. 4B ) formed through the lower jaw 16. The middle pin 46 slidably engages the upper side of the lower jaw 16 in cooperation with the firing beam cap 44. This allows the firing beam 14 to reliably space the end effector 12 during firing. By way of example only, firing beam (14) and / or associated lockout features may be constructed and operative in accordance with at least some of the teachings of U.S. Patent No. 9,717,497, entitled "Lockout Feature for Movable Cutting Member of Surgical Instrument," issued August 1, 2017, the disclosure of which is incorporated herein by reference. Other suitable forms that firing beam (14) may take will be apparent to those skilled in the art in view of the teachings herein.

[0016] Figure 3 shows the firing beam (14) of this example positioned proximally and the anvil (18) pivoted to an open position to allow an unused staple cartridge (37) to be removably loaded into the channel of the lower jaw (16). As seen in Figures 5 and 6, the staple cartridge (37) of this example includes a cartridge body (70) that presents an upper deck (72) and is coupled to a lower cartridge tray (74). As seen in Figure 3, a vertical slot (49) is formed through a portion of the staple cartridge (37). As also seen in Figure 3, three rows of staple openings (51) are formed through the upper deck (72) on one side of the vertical slot (49), and another set of three rows of staple openings (51) are formed through the upper deck (72) on the other side of the vertical slot (49). Of course, any other suitable number of rows of staples (e.g., two rows, four rows, etc.) may be provided. 4A-6, the wedge-shaped sled 41 and the plurality of staple drivers 43 are captured between the cartridge body 70 and the tray 74, with the wedge-shaped sled 41 positioned proximal to the staple drivers 43 prior to firing the instrument 10 to eject the staples 47. The wedge-shaped sled 41 is longitudinally movable within the staple cartridge 37, while the staple drivers 43 are vertically movable within the staple cartridge 37. The staples 47 are also positioned within the cartridge body 70 above their corresponding staple drivers 43. Specifically, each staple 47 is driven vertically within the cartridge body 70 by the staple driver 43 to drive the staple 47 out of the associated staple opening 51. As can be seen in Figures 4A and 4B, as well as Figure 6, wedge-shaped sled (41) presents an angled cam surface that urges staple driver (43) upward as wedge-shaped sled (41) is driven distally through staple cartridge (37).

[0017] By way of example only, staple cartridge (37) may be constructed and operative in accordance with at least a portion of the teachings of U.S. Patent No. 9,517,065, entitled "Integrated Tissue Positioning and Jaw Alignment Features for Surgical Stapler," issued December 13, 2016, the disclosure of which is incorporated herein by reference in its entirety. Other suitable forms that staple cartridge (37) may take will be apparent to those skilled in the art in view of the teachings herein.

[0018] As shown in Figures 4A and 4B, when the end effector 12 is closed by distally advancing the closure tube 32 and closure ring 33, the firing beam 14 advances and the upper pin 38 enters the longitudinal anvil slot 42, thereby engaging the anvil 18. A pusher block 80 (shown in Figure 5) is located at the distal end of the firing beam 14 and is configured to engage the wedge-shaped sled 41 such that, when the firing trigger 28 is actuated, the wedge-shaped sled 41 is pushed distally by the pusher block 80 as the firing beam 14 advances distally through the staple cartridge 37. During such firing, the cutting edge 48 of the firing beam 14 enters the vertical slot 49 of the staple cartridge 37, severing the tissue clamped between the staple cartridge 37 and the anvil 18. As shown in FIGS. 4A and 4B, the middle pin (46) and pusher block (80) together actuate the staple cartridge (37) by entering the vertical slot (49) in the staple cartridge (37), driving the wedge-shaped sled (41) into upward camming contact with the staple driver (43), which forces the staple (47) out of the staple opening (51) and into forming contact with the staple-forming pocket (53) (shown in FIG. 3) on the inner surface of the anvil (18). FIG. 4B depicts the firing beam (14) fully translated distally after the tissue has been severed and stapled. It should be understood that the staple-forming pocket (53) has been intentionally omitted from the views of FIGS. 4A and 4B, but that the staple-forming pocket (53) is shown in FIG. 3. It should also be understood that the anvil (18) has been intentionally omitted from the view of FIG. 5.

[0019] FIG. 7 shows the end effector 12 actuated with a single stroke through layers 92, 94 of tissue 90. As shown, the cutting edge 48 (hidden in FIG. 7) cuts the tissue 90 while the staple driver 43 drives three alternating rows of staples 47 through the tissue 90 on each side of the cut line created by the cutting edge 48. In this example, all of the staples 47 are oriented substantially parallel to the cut line, although it should be understood that the staples 47 may be positioned in any suitable orientation. In this example, after the first stroke is completed, the end effector 12 is withdrawn from the trocar, the spent staple cartridge 37 is replaced with a new staple cartridge, and the end effector 12 is then reinserted through the trocar or incision to reach the stapling site and perform additional cutting and stapling. This process may be repeated until the desired number of cuts and staples 47 have been applied. The anvil 18 may need to be closed to facilitate insertion and removal through the trocar, and may need to be opened to facilitate replacement of the staple cartridge 37.

[0020] In this variation, the instrument 10 further includes an electric motor (not shown) housed within the handle portion 20 that provides motorized control of the firing beam 14. By way of example only, such motorization may be provided in accordance with at least some of the teachings of U.S. Pat. No. 9,622,746, entitled "Distal Tip Features for End Effector of Surgical Instrument," issued April 18, 2017, the disclosure of which is incorporated herein by reference in its entirety, and / or U.S. Pat. No. 8,210,411, entitled "Motor-Driven Surgical Instrument," issued July 3, 2012, the disclosure of which is incorporated herein by reference in its entirety. Other suitable components, features, and configurations for providing motorization of the firing beam 14 will be apparent to those skilled in the art in view of the teachings herein. It should also be understood that in some other variations, manual drive of the firing beam 14 may be provided such that a motor may be omitted.

[0021] In motorized versions of the instrument 10, the instrument 10 may also include a manual return switch, or bailout switch (not shown), positioned on or within the handle portion 20, such as in or below a user-accessible panel or "bailout door" (not shown), configured to allow the operator to initiate rapid proximal retraction of the firing beam 14 during the firing stroke. That is, the bailout switch can be manually activated when the firing beam 14 has only partially advanced distally. Such a bailout switch can provide additional functionality in accordance with at least some of the teachings of U.S. Pat. No. 9,622,746, incorporated by reference above.

[0022] The instrument 10 of this example further includes a display screen 117 on the exterior of the handle portion 20 such that the display screen 117 is easily viewable by a user. The display screen 117 may be configured to provide the user with a visual indication of one or more conditions of the instrument 10, such as the remaining power level of the battery 142 (e.g., a removable battery pack), and / or various other conditions of the instrument 10.

[0023] II. End-effector mechanism for measuring tissue electrical impedance In some instances, it may be desirable to configure the end effector (12) of the surgical stapling instrument (10) to sense at least one of the presence (including its longitudinal position), absence, or characteristics of in vivo matter, such as patient tissue, positioned between the jaws (16, 18) during a surgical procedure. As used herein, the term "in vivo matter" encompasses any matter, biological or non-biological, that may be located within a patient's body cavity during which a surgical procedure is being performed using the instrument (10).

[0024] Various exemplary electrode arrays suitable for use with the end effector (12) are described in more detail below, each including one or more cooperating electrode pairs laterally opposed to one another, electrically coupled to an electrical energy source, and configured to deliver bipolar radio frequency (RF) energy to the biological material at relatively low diagnostic levels (i.e., non-therapeutic RF energy, also referred to herein as electrical signals). In particular, each cooperating electrode pair includes a first electrode positioned between the end effector jaws (16, 18) and configured to deliver an electrical signal to the biological material in contact with the electrode, and a second electrode configured to receive the electrical signal after passing through tissue. In other variations of the exemplary embodiments described below, the surgical instrument may include a first electrode presented by the end effector and a second electrode located remotely from the end effector, the first and second electrodes cooperating to direct a monopolar RF electrical signal through the biological material. In such variations, the second electrode may be in the form of an electrical grounding pad secured to the patient's skin, for example, as disclosed in any of the references incorporated herein by reference.

[0025] 8-13 illustrate several exemplary electrode arrays, each having one or more cooperating electrode pairs configured to transmit RF electrical signals through biological material such as tissue. In each exemplary variation, the electrode array is shown and described as being integrated into a single end effector jaw, although in other variations, the electrode array may be integrated into both end effector jaws, such that a given cooperating electrode pair includes a first electrode on a first end effector jaw and a second electrode on a second end effector jaw.

[0026] As described in more detail below in connection with FIGS. 14-18 , the electrodes of the electrode array may be electrically coupled to a miniature tissue sensing circuit integrated into a component of the end effector 12, such as the lower jaw 16 or staple cartridge 37, and configured to measure the electrical impedance of the biological material positioned between and in contact with a given pair of electrodes. Based on this measured electrical impedance, the tissue sensing circuit may determine at least one of the presence of tissue within the biological material, the absence of tissue within the biological material, or a characteristic of tissue forming at least a portion of the biological material. The instrument 10 may then take responsive action, which may include providing a notification to the operator, based on the impedance measurement and determination. While the exemplary configurations described below are disclosed in connection with a surgical stapling instrument, it will be understood that such configurations may also be applied to various other types of surgical instruments, such as, for example, surgical instruments operable to grasp tissue and / or treat tissue with ultrasonic and / or RF energy.

[0027] A. Exemplary end effector electrode array Referring now to FIG. 8 , an exemplary electrode array (800) is shown in accordance with at least one non-limiting embodiment of the present disclosure. While the electrode array (800) is shown as a component of the lower jaw (16) of the end effector (12) in FIGS. 1-7 , it should be understood that the electrode array (800) may be implemented in the jaws of various other types of surgical instruments. As shown in FIG. 8 , the upper jaw (16) of the end effector (12) may define an elongated channel (821) that transverses the longitudinal axis (L) of the end effector (12). Specifically, the channel (821) may be defined by one or more sidewalls (825A, 825B) of the lower jaw (16) that extend along the longitudinal axis (L) on either side of the longitudinal axis (L). For example, the electrode array (800) may include eight pairs of electrodes (822, 824), each having a rectangular shape and constructed from titanium, with each electrode (822, 824) configured to cooperate with a laterally opposing electrode (822, 824) to transmit RF electrical signals through tissue positioned in contact with the two electrodes (822, 824). In other variations, the array (800) may include electrodes (822, 824) of various numbers, shapes, and / or materials, depending on the intended application and / or user preference. In further implementations, certain electrodes (824) of the array (800) may be configured differently relative to other electrodes (822). For example, certain electrodes (824) may be positioned on either side of a cutting line (826), with the electrodes (824) configured to provide increased resolution on either side of the cutting line (826).

[0028] According to another non-limiting embodiment of FIG. 8 , the electrode array (800) may include one or more electrodes (822, 824) integrated into the side walls (825A, 825B) of the lower jaw (16) of the end effector (12). Specifically, each electrode (822, 824) may be overmounted or overmolded onto the walls (825A, 825B). Of course, other integration means may be used to achieve a similar effect. In some implementations, certain electrodes (824) may be positioned around the cutting line (826) of the end effector (12), such that, when activated, these electrodes (824) can cut tissue around the cutting line (826). In other variations, the electrode array (800) may be integrated into the upper jaw (18) of the end effector (12).

[0029] Referring now to Figure 9, another end effector (900) is shown in accordance with at least one non-limiting example of the present disclosure. According to some implementations, as shown in Figure 9, the end effector (900) may include an array of electrodes (904) mounted on separate consumables (906) configured to be inserted into a channel (902) defined by side walls (903A, 903B) of the end effector (900), each electrode (904) configured to cooperate with a laterally opposing electrode (904) to transmit an RF electrical signal through tissue positioned in contact with the two electrodes (904). The channel (902) and side walls (903A, 903B) may be configured to accommodate the separate consumables (906). For example, the side walls (903A, 903B) can include an inner surface constructed of a conductive material such that when a separate consumable is inserted into the channel (902), the conductive material is positioned in electrical communication with the electrode (904). Additionally or alternatively, the channel can include one or more electrical contacts configured to position the electrode (904) in electrical communication with a flexible conductor (908) capable of carrying a multiplexed signal, the flexible conductor (908) traversing the channel (902).

[0030] Thus, in some implementations, as shown in FIG. 9 , the array of electrodes (904) is attached to a separate consumable (906) and can thus be selectively clipped into the channel (902). In this manner, a single end effector (900) can be configured to selectively accommodate multiple separate consumables (906), with each separate consumable (906) including a different array of electrodes (904) in various configurations. Additionally, the separate consumables (906) can define a second channel (912) configured to accommodate a surgical cartridge (e.g., staple cartridge, electrosurgical cartridge, etc.). Thus, various combinations of separate consumables (906) and cartridges can be used with the same end effector (900). Additionally, the electrodes (904) can receive and transmit signals via flexible conductors (908), which can be used to generate insights according to the previously disclosed techniques, regardless of the cartridge type loaded within the end effector (900). According to some non-limiting embodiments, a flexible conductor (908) can be routed through the end effector (900) and the surgical instrument.

[0031] 10A-10C , another end effector (1000) is shown in accordance with at least one example of the present disclosure. In some implementations, as shown, the end effector (1000) can house a cartridge (1006) configured to perform a surgical operation (e.g., a staple cartridge, an electrosurgical cartridge, etc.), and an array of electrodes 1004 can be disposed on the cartridge (1006) itself. Each electrode (1004) is configured to cooperate with a laterally opposing electrode (1004) to transmit an RF electrical signal through tissue positioned in contact with the two electrodes (1004). 10A-10B, the side walls 1003A, 1003B of the end effector 1000, in this case defined by the tray of a cartridge 1006 similar to the tray 74, can again define a channel 1002, which can be configured to receive the body of the cartridge 1006. The end effector 1000 can further include flexible conductors 1008 capable of carrying multiplexed signals, the flexible conductors traversing through the channel 1002. In some implementations, the flexible conductors 1008 can be routed through the end effector 1000 and surgical instrument in a manner similar to that described with reference to the end effector 900 of FIG. 9.

[0032] For example, the side walls (1003A, 1003B) can include an inner surface constructed of a conductive material such that the conductive material is placed in electrical communication with the electrode (1004) when a separate consumable is inserted into the channel (1002), as shown in Figure 10C. Alternatively, the channel can include one or more electrical contacts configured to place the electrode (1004) in electrical communication with a flexible conductor (1008) capable of carrying a multiplexed signal, the flexible conductor (1008) traversing the channel (1002).

[0033] In a further implementation, as shown in FIG. 10C , insertion of a cartridge 1006 into an end effector 1000 is illustrated according to at least one non-limiting embodiment of the present disclosure. According to the non-limiting embodiment of FIG. 10C , the end effector 1000 can include conductive elements 1012 configured to electrically connect with corresponding conductive elements 1010 on the cartridge 1006. The conductive elements 1010, 1012 can be further configured for multiplexed signal transmission such that multiplexed signals transmitted through flexible conductors 1008 of the end effector 1000 can be communicated to and from each electrode 1004 of an array positioned on the cartridge 1006. In a further implementation, an array of electrodes 1004 can be integrated onto the cartridge 1006, which can be a consumable item. The electrode 1004 may be electrically integrated within the cartridge 1006 via an electrical connection between a multiplexed integrated circuit within the cartridge and the conductive elements 1010, 1012. Because the cartridge 1006 may contain multiplexed electronics, the conductive elements 1010, 1012 should simplify the interface between the end effector 1000 and the cartridge 1006.

[0034] 11A , another end effector (1100A) is shown in accordance with at least one non-limiting embodiment of the present disclosure. The end effector (1100A) may be configured to accommodate a hybrid cartridge (1106A), with an array of electrodes (1104A) positioned on the cartridge (1106A). Each electrode (1104A) is configured to cooperate with a laterally opposing electrode (1104A) to transmit an RF electrical signal through tissue positioned in contact with the two electrodes (1104A). Each electrode (1104A) may be configured to electrically communicate with a flexible conductor (1108) capable of carrying multiplexed signals. In another implementation, when the cartridge (1106A) is mounted within the end effector (1100A), the flexible conductor (1108) may traverse through a channel defined by the end effector (1100A) and may be routed through the end effector (1100A) and surgical instrument in a manner similar to that described herein.

[0035] Referring now to FIG. 11B, a similar, albeit subtly different, end effector (1100B) is shown in accordance with at least one non-limiting embodiment of the present disclosure. In particular, the array of electrodes (1104B) differs from the electrodes (1104A) of FIG. 11A. Accordingly, multiple conductive elements (1112) corresponding to each electrode (1104B) are disposed within each wall (1103A, 1103B) of the end effector (1100B). Thus, each electrode (1104B) of the array can receive its intended signal from the multiplexed signal traversing the flexible conductor (1108).

[0036] 11A-11B, it will be appreciated that in some implementations, an array of electrodes (1104A, 1104B) can be positioned on a cartridge (1106A, 1106B), and the cartridge can be electrically configured with one or more electrical surfaces (e.g., metal plating, metal strips bent around the sides, vias through the cartridge, etc.) for intended connection of each electrode (1104A, 1104B) to the appropriate portion of the flexible conductor (1108). Thus, although multiplexing occurs within the end effector (1100A, 1100B), each electrode (1104A, 1104B) still receives the appropriate signal via an electrical connection.

[0037] 12, another end effector 1200 is shown in accordance with at least one non-limiting example of the present disclosure. Similar to the end effectors 1100A, 1100B of FIGS. 11A-11B, an array of electrodes 1204 may be integrated into the cartridge 1206 itself, with each electrode 1204 configured to cooperate with a laterally opposing electrode 1204 to transmit an RF electrical signal through tissue positioned in contact with the two electrodes 1204. However, multiplexing may occur within either the cartridge 1206 or the end effector 1200 via a flexible conductor 1208 capable of carrying the multiplexed signal. In any event, the end effector (1200) of FIG. 12 may further include a wireless communication module 1214 configured to wirelessly transmit and receive multiplexed signals to and from the control circuitry and / or surgical hub via an infrastructure network (e.g., WiFi, cellular, etc.) or an ad-hoc network (e.g., Bluetooth, near field communication, RFID, etc.).

[0038] Thus, wireless communication module 1214 can function as a communications interface between end effector 1200 and the surgical hub and / or control circuitry, thereby eliminating the need for the routing described with reference to Figures 10 and 11. It should be understood that wireless communication module 1214 can be similarly applied to any of the surgical instruments and / or end effectors disclosed herein, thereby simplifying, and in some embodiments eliminating, the routing of the flexible conductors disclosed herein.

[0039] Referring now to FIG. 13 , another end effector (1300) is shown in accordance with at least one non-limiting aspect of the present disclosure. As shown, the end effector (1300) may include a first jaw and a second jaw. For example, the second jaw can be configured as an anvil of the end effector (1300), and a separate consumable (1306) can be configured to be selectively coupled to the second jaw. While the separate consumable (906) in FIG. 9 is shown coupled to the lower jaw of the end effector (900) in FIG. 9 , the separate consumable (1306) can be coupled to the second, or upper, jaw (1302) of the end effector (1300). Nevertheless, an array of electrodes (1304) can be coupled to the separate consumable (1306) and, when coupled to a conductive element on the second jaw (1302), can be electrically coupled to a flexible conductor (1308). Each electrode 1304 is configured to cooperate with a laterally opposing electrode 1304 to transmit an RF electrical signal through tissue positioned in contact with the two electrodes 1304. Flexible conductors 1308 may be capable of carrying multiplexed signals, with the flexible conductors 1308 traversing through the end effector 1300 and surgical instrument in a manner similar to that described with reference to Figures 9-11. Alternatively, the wireless implementation of Figure 12 can be employed to transmit signals to and from the array of electrodes 1204.

[0040] In an alternative variation of any of the exemplary electrode arrays described above, each pair of laterally opposed electrodes disposed along the length of the end effector may be electrically isolated from one another and configured to communicate independently with the surgical instrument's controller. Based on electrical impedance readings associated with various different electrode pairs, the controller can determine the longitudinal position of tissue located between the end effector jaws relative to the end effector.

[0041] B. Exemplary Tissue Sensing Circuit 14 illustrates a tissue sensing circuit (1400) coupled to one or more tissue sensing electrodes (1450), such as two or more pairs of electrodes (1450), each pair configured to deliver bipolar RF energy to tissue. The electrodes (1450) may be integrated into a surgical instrument effector, such as an end effector (12), and may be operable in any of the exemplary manners disclosed above. As shown, the tissue sensing circuit (1400) may include various components. For example, the tissue sensing circuit (1400) may receive a digital-to-analog converter port connected to a fixed fundamental frequency (f c The tissue sensing circuit (1400) may include a digital microcontroller (1410) configured to synthesize an output sinusoidal signal having a .times. ...

[0042] In some implementations, as shown in FIG. 14 , the microcontroller (1410) may replicate or function as analog circuitry. Thus, the microcontroller (1410) may have, access, or include advanced embedded analog, mixed-signal, and digital signal processing (DSP) capabilities. While various microcontroller configurations are discussed herein, it should be understood that any feasible microcontroller may be used. As non-limiting examples, the microcontrollers STM32F3 and / or STM32G4 should be sufficient to perform the methods disclosed herein.

[0043] 15A and 15B, portions of another end effector (1500) are shown in accordance with at least one implementation of the present disclosure. In some implementations, as shown, the end effector (1500) can house a cartridge (1506) configured to perform a surgical operation (e.g., a staple cartridge, an electrosurgical cartridge, etc.), and an array of electrodes can be disposed on the cartridge (1506) itself. In some implementations, as shown schematically in FIG. 15A, a tissue sensing circuit (1501), which can be similar to the tissue sensing circuit (1400) of FIG. 14, can be present on or embedded within an interior surface of the lower jaw (16) of the end effector (1500), such as a sidewall or floor of the lower jaw (16), such that the tissue sensing circuit (1501) is covered by the cartridge (1506) when seated within the lower jaw (16). In this implementation, the tissue sensing circuit (1501) is permanently attached to or housed within the end effector (1500) (specifically, the jaw (16)) and is therefore not discarded with the cartridge (1506) between firings of the end effector (1500) and can therefore be reused for multiple firings, thereby saving the user costs.

[0044] Alternatively, in some implementations, such as that shown in FIG. 15B , the tissue sensing circuit 1501 may be present on or housed within a cartridge 1506 that is inserted into the end effector 1500. For example, as shown schematically, the tissue sensing circuit 1501 may be embedded within the tapered distal end of the body of the cartridge 1506. In this implementation, the tissue sensing circuit 1501 is permanently attached to or housed within the cartridge 1506 and is discarded along with the cartridge 1506 after it is fired and removed from the end effector 1500. Various other implementations may exist regarding the placement of the tissue sensing circuit 1501 to allow for single or multiple use. In further implementations, tissue sensing circuitry (1501) may be provided in both the end effector jaw (16) and the cartridge (1506), which may provide redundancy in the event of a failure or malfunction.

[0045] C. Description of System Operation and Capabilities The system discussed herein and illustrated in FIGS. 1-15B provides a surgical stapler instrument (10) configured to clamp tissue using an end effector (12). Once securely clamped, electrodes (e.g., electrodes shown in FIGS. 8-13) within the end effector (12) apply a non-therapeutic (i.e., low-voltage) waveform to the tissue. The return waveform is then evaluated to measure and / or calculate (e.g., using the microcontroller of FIG. 14) the tissue impedance. More specifically, the system applies non-therapeutic energy via one or more subcircuits to the extracellular and intracellular fluids present within a given (e.g., clamped) region of tissue to determine the phase and magnitude of the tissue impedance within the jaws. The system can then relay information related to the tissue, such as, for example, tissue type, tissue phase, tissue margin, etc. Using this related information, the system can not only verify that the appropriate tissue is clamped between the jaws, but also determine whether any non-tissue material is present between the jaws.

[0046] FIG. 16 illustrates an exemplary impedance triangle (1601) that may be implemented by the tissue sensing circuit (1400) to determine the electrical impedance of tissue placed in contact with a pair of electrodes of a surgical instrument end effector, such as the end effector (12). As will be appreciated by those skilled in the art, human tissue may tend to be capacitive in nature, while wires, tools, staples, implants, and the like may tend to be inductive in nature. Thus, as can be seen from the exemplary impedance triangle (1601), the “resistance” (1602) of each object in the circuit is measured using the electrodes. The system can also determine the “capacitive reactance” (1603) of each object in the circuit and the inductive reactance (1604) of each object in the circuit (1400). As discussed above and clearly illustrated in FIG. 16, electrodes (e.g., those shown in FIGS. 8-14) transmit and receive electrical signals to and from the patient's tissue via a microcontroller. As will be appreciated by those skilled in the art, the patient's extracellular and intracellular fluids have capacitive reactance (1603). The "reactance" (1605) can then be calculated by determining the difference between the capacitive reactance and the inductive reactance using:

[0047] Formula 1:

[0048]

number

[0049] As shown in FIG. 16, “Impedance” 1606 can be determined using: Formula 2:

[0050]

number

[0051] FIG. 17 shows a set of example waveforms that may be generated and measured by tissue sensing circuit 1400 to determine the phase of the circuit's current and voltage, as discussed herein. As will be appreciated by those skilled in the art, if the circuit contains only resistive items, the current and voltage will remain in phase, as shown in graph 1701 and phasor diagram 1704. Alternatively, if the circuit has capacitive objects, or is more capacitive than inductive, the voltage wave will lead the current wave, as shown in graph 1702 and phasor diagram 1705. Finally, if the circuit has inductive objects, or more inductive objects than capacitive objects, the voltage will lag the current, as shown in graph 1703 and phasor diagram 1706. As discussed above and shown in FIG. 16, human tissue tends to be capacitive in nature, while wires, tools, staples, implants, etc., may tend to be inductive in nature.

[0052] Thus, if the current and voltage measurements result in a current-leading waveform (1702), it indicates that the material between the electrodes is "capacitive" and therefore falls into the category of tissue or fluid (e.g., 1603). Alternatively, if the current and voltage measurements result in a current-lagging waveform (1703), it indicates that the material between the electrodes is "inductive" and therefore not tissue or fluid (e.g., 1603). Thus, as discussed herein, the electrodes (e.g., 1450) send and receive electrical signals to and from the end effector that are believed to be in contact with patient tissue. The waveforms are then analyzed by the tissue sensing circuitry (1400) to determine whether the current is leading or lagging the voltage (e.g., 1702 vs. 1703), which can then be used to ascertain what is in contact with the electrodes.

[0053] As discussed herein, the system may pass a non-therapeutic waveform through a portion of patient tissue to help identify the tissue type as well as any foreign material. Thus, in some versions, the system may pass waveforms of varying frequencies (e.g., in series and / or parallel) to improve the accuracy of the determination. Thus, in some implementations, multiple waveforms of various frequencies may be added or summed together to create a multi-sine waveform.

[0054] FIG. 18 illustrates an exemplary process 1800 utilizing the tissue sensing circuit 1400 to determine the presence and type of tissue placed in contact with an electrode 1450. In step 1801, a user or software can automatically activate the tissue sensing circuit 1400 (e.g., the microcontroller 1410) to synthesize a non-therapeutic (e.g., low-voltage) signal having a fixed fundamental frequency. Once the waveform is synthesized in step 1801, the surgical instrument 10 then uses the microcontroller 1410 to facilitate delivery of an electrical signal to at least one electrode 1450, which is in contact with the patient's tissue, in step 1802. While the generated waveform is being delivered to the patient's tissue via the electrode 1450, a return signal is measured by the microcontroller 1410 in step 1803, thereby confirming the presence of tissue at the location of the electrode 1450. In step 1804, the microcontroller 1410 determines at least one characteristic of the detected tissue of the patient, such as tissue type, based on the measurement of the return signal. It will be appreciated that based on the lack of a return signal, the microcontroller 1410 may determine that no tissue is present at the location of the electrode 1450. Based on the determined presence and characteristics of the detected tissue, or based on the determined absence of tissue, the microcontroller 1410 may then direct a responsive action to be taken by the surgical instrument, such as providing an associated indication (e.g., visual, audible, and / or tactile) to the operator.

[0055] III. Combination Examples The following examples relate to various non-exhaustive ways in which the teachings herein may be combined or applied. The following examples are not intended to limit the scope of any claims that may be presented in this application or at any time in a subsequent filing of this application. No disclaimer is intended. The following examples are provided merely for illustrative purposes. It is contemplated that the various teachings herein may be configured and applied in many other ways. It is also contemplated that some variations may omit certain features referred to in the following examples. Accordingly, none of the aspects or features referred to below should be deemed critical unless later expressly indicated otherwise by the inventors or their successors. If a claim presented in this application or a subsequent application related to this application includes additional features other than those referred to below, those additional features should not be deemed added for any reasons of patentability. [Example]

[0056] A surgical instrument comprising: (a) an end effector configured to interact with biological matter of a patient, the end effector including: (i) a first jaw; (ii) a second jaw configured to cooperate with the first jaw to clamp the biological matter; and (iii) a first electrode positioned between the first and second jaws and configured to directly contact and deliver an electrical signal to the biological matter; (b) a second electrode configured to receive an electrical signal from the first electrode; and (c) an electrical circuit housed within the end effector. and an electrical circuit including a microcontroller configured to: (i) control delivery of an electrical signal to the first electrode such that the electrical signal passes from the first electrode, through the biological material, and to the second electrode; (ii) determine an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; and (iii) determine at least one of (A) a presence of tissue in the biological material, (B) an absence of tissue in the biological material, or (C) a characteristic of tissue forming at least a portion of the biological material based on the electrical impedance. [Example]

[0057] 2. The surgical instrument of Example 1, wherein the electrical circuitry is further configured to generate the electrical signal using a microcontroller, the electrical signal comprising a composite waveform. [Example]

[0058] The surgical instrument described in Example 2, wherein the composite waveform has a fixed single fundamental frequency. [Example]

[0059] 4. The surgical instrument of any one of Examples 2 to 3, wherein the electrical circuit further comprises a bandpass filter (BPF). [Example]

[0060] The surgical instrument of Example 4, wherein the electrical circuit is configured to pass the composite waveform through a BPF before delivery to the first electrode. [Example]

[0061] 6. The surgical instrument of any one of Examples 1 to 5, wherein the electrical circuit further comprises a voltage controlled current source (VCCS) circuit. [Example]

[0062] 7. The surgical instrument of example 6, wherein the electrical circuitry is further configured to convert the electrical signal into a current-limiting signal using a VCCS circuit. [Example]

[0063] 8. The surgical instrument of any of Examples 1 to 7, wherein the electrical circuitry further comprises an operational amplifier, the electrical circuitry being further configured to buffer and amplify the electrical signal using the operational amplifier before returning the electrical signal from the second electrode to the microcontroller. [Example]

[0064] 9. The surgical instrument of any of Examples 1 to 8, wherein the electrical circuit is further configured to extract and analyze at least one feature from the electrical signal, the at least one feature being a feature selected from the group consisting of an amplitude of the electrical signal and a phase shift of the electrical signal. [Example]

[0065] 10. The surgical instrument of any of Examples 1 to 9, wherein the electrical circuit is further configured to identify a current waveform and a voltage waveform associated with the electrical signal delivered to the biological material. [Example]

[0066] 11. The surgical instrument of any one of Examples 1 to 10, wherein the electrical circuit is configured to determine electrical impedance based on capacitive reactance and inductive reactance of the biological material. [Example]

[0067] 12. The surgical instrument of any of Examples 1 to 11, wherein the first electrode and the second electrode are presented by an end effector. [Example]

[0068] 13. The surgical instrument of any of Examples 1 to 12, wherein the first electrode is presented by the end effector and the second electrode is located remotely from the end effector. [Example]

[0069] A surgical instrument described in any of Examples 1 to 13, wherein the end effector is removably coupled to the second jaw and further comprises a staple cartridge having a plurality of staples, and the microcontroller is fixed to a body of the staple cartridge. [Example]

[0070] 15. The surgical instrument of any of Examples 1 to 14, wherein the microcontroller is disposed on an interior surface of one of the first jaw or the second jaw. [Example]

[0071] A surgical instrument comprising: (a) a body; (b) a shaft extending distally from the body; (c) an end effector at a distal end of the shaft, the end effector including: (i) a first jaw having a plurality of staple forming pockets configured to form staples; (ii) a second jaw configured to cooperate with the first jaw to clamp biological material of a patient; (iii) a staple cartridge removably coupled to the second jaw and having a plurality of staples; (d) first and second electrodes configured to deliver an electrical signal to biological material positioned between the first and second jaws; and (e) a first electrode configured to deliver an electrical signal to the biological material electrically coupled to the first and second electrodes. and an electrical circuit including a microcontroller coupled to and fixed to a portion of one of the first jaw, the second jaw, or the staple cartridge, the electrical circuit being configured to: (i) control delivery of an electrical signal to the first electrode such that the electrical signal passes from the first electrode through the biological material to the second electrode; (ii) determine an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; and (iii) determine at least one of (A) the presence of tissue in the biological material, (B) the absence of tissue in the biological material, or (C) a characteristic of tissue forming at least a portion of the biological material based on the electrical impedance. [Example]

[0072] 17. The surgical instrument of Example 16, wherein the first electrode and the second electrode are presented by an end effector. [Example]

[0073] 18. The surgical instrument of any of Examples 16 to 17, wherein the electrical circuit further includes at least one of a bandpass filter (BPF), a voltage controlled current source (VCCS) circuit, or an operational amplifier, and the electrical circuit is configured to perform an operation selected from the group consisting of: (a) passing the composite waveform through the BPF before delivering the electrical signal to the first electrode; (b) converting the electrical signal to a current-limited signal using the VCCS circuit; and (c) buffering and amplifying the electrical signal using the operational amplifier before returning the electrical signal from the second electrode to the microcontroller. [Example]

[0074] 19. A surgical instrument according to any one of Examples 16 to 18, wherein the microcontroller is configured to determine the electrical impedance based on the capacitive reactance and inductive reactance of the biological material. [Example]

[0075] 1. A method of operating a surgical instrument having a first electrode and a second electrode and an end effector housing a microcontroller, the method including: (a) using the microcontroller to control delivery of an electrical signal to the first electrode, the first electrode being configured to directly contact and deliver the electrical signal to biological material clamped by the end effector; (b) receiving the electrical signal at the second electrode after the electrical signal passes from the first electrode through the biological material; (c) determining, by the microcontroller, an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; and (d) using the microcontroller to determine, based on the electrical impedance, at least one of: (i) the presence of tissue in the biological material; (ii) the absence of tissue in the biological material; or (iii) a characteristic of tissue forming at least a portion of the biological material.

[0076] IV. Other It should be understood that any variation of the apparatus described herein may include various other features in addition to or in place of those described hereinabove. By way of example only, the apparatus devices described herein may also include one or more of the various mechanisms disclosed in any of the various references incorporated herein by reference. Various suitable ways in which such teachings may be combined will be apparent to those skilled in the art.

[0077] While the examples herein have been described primarily in the context of electrosurgical instruments, it should be understood that the various teachings herein are readily applicable to a variety of other types of devices. By way of example only, the various teachings herein may be readily applied to other types of electrosurgical instruments, such as tissue graspers, tissue retrieval pouch placement instruments, surgical staplers, surgical clip appliers, ultrasonic surgical instruments, etc. It should also be understood that the teachings herein may be readily applied to any of the instruments described in any of the documents cited herein, and thus the teachings herein may be readily combined in various ways with the teachings of any of the documents cited herein. Other types of instruments into which the teachings herein may be incorporated will be apparent to those skilled in the art.

[0078] It should be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described herein can be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described herein. Thus, the above teachings, expressions, embodiments, examples, etc. should not be considered in isolation from one another. Various suitable ways in which the teachings herein can be combined will be readily apparent to those skilled in the art in light of the teachings herein. Such modifications and variations are intended to be within the scope of the claims.

[0079] It is to be understood that any patent, publication, or other disclosure material stated to be incorporated by reference herein, in part or in whole, is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions or other disclosure content set forth in this disclosure. As such, and to the extent necessary, the disclosure explicitly set forth herein shall supersede any conflicting statement incorporated herein by reference. Any material or portion thereof stated to be incorporated by reference herein that conflicts with existing definitions or other disclosure content set forth in this application is incorporated only to the extent that no conflict arises between the incorporated material and the existing disclosure content.

[0080] Variations of the above-described devices may be applied not only to traditional medical procedures and surgeries performed by medical professionals, but also to robotic-assisted medical procedures and surgeries. By way of example only, the various teachings herein may be readily incorporated into robotic surgical systems such as the DAVINCI™ system by Intuitive Surgical, Inc. (Sunnyvale, California). Similarly, those skilled in the art will recognize that the various teachings herein may be readily combined with the various teachings of U.S. Patent No. 6,783,524, entitled "Robotic Surgical Tool with Ultrasound Cauterizing and Cutting Instrument," issued August 31, 2004, the disclosure of which is incorporated herein by reference in its entirety.

[0081] The above-described variations may be designed to be disposed of after a single use, or they may be designed to be used multiple times. In either case, the variations may be reconditioned for reuse after at least one use. Reconditioning may include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular parts, and subsequent reassembly. Specifically, some device variations may be disassembled, and any number of particular parts or components of the device may be selectively replaced or removed in any combination. Upon cleaning and / or replacement of particular parts, some device variations may be reassembled for subsequent use either at a reconditioning facility or by an operator immediately prior to a procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning / replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0082] By way of example only, the variations described herein may be sterilized before and / or after the procedure. In one sterilization technique, the device is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and device may then be placed in a radiation field that can penetrate the container, such as gamma radiation, x-rays, or a high-energy electron beam. The radiation may kill bacteria on the device and in the container. The sterilized device may then be stored in the sterile container for later use. The device may also be sterilized using any other technique known in the art, including, but not limited to, beta or gamma radiation, ethylene oxide, or steam.

[0083] While various embodiments of the present invention have been illustrated and described, further adaptations of the methods and systems described herein may be achieved by appropriate modifications by those skilled in the art without departing from the scope of the present invention. While some of such possible modifications have been mentioned, other modifications will be apparent to those skilled in the art. For example, the examples, embodiments, geometries, materials, dimensions, proportions, steps, etc. discussed above are illustrative and not required. Accordingly, it will be understood that the scope of the present invention should be considered in terms of the following claims, and is not limited to the details of structure and operation shown and described in this specification and drawings.

[0084] [Embodiment] (1) A surgical instrument, (a) an end effector configured to interact with biological matter in a patient, the end effector comprising: (i) a first jaw; (ii) a second jaw configured to cooperate with the first jaw to clamp the biological material; and (iii) a first electrode positioned between the first jaw and the second jaw and configured to directly contact and deliver an electrical signal to the biological material; and (b) a second electrode configured to receive the electrical signal from the first electrode; and (c) an electrical circuit housed within the end effector, the electrical circuit including a microcontroller; (i) controlling delivery of the electrical signal to the first electrode such that the electrical signal passes from the first electrode through the biological material to the second electrode; (ii) determining an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; (iii) based on the electrical impedance, (A) the presence of tissue in the biological material; (B) the absence of tissue in the biological material; or (C) a property of a tissue forming at least a portion of the biological material; and A surgical instrument comprising: (2) The surgical instrument of claim 1, wherein the electrical circuit is further configured to generate the electrical signal using the microcontroller, and the electrical signal includes a composite waveform. (3) The surgical instrument of claim 2, wherein the composite waveform has a fixed single fundamental frequency. (4) A surgical instrument according to any one of claims 1 to 3, wherein the electrical circuit further comprises a bandpass filter (BPF). (5) The surgical instrument of embodiment 4, wherein the electrical circuit is configured to pass the composite waveform through the BPF before delivery to the first electrode.

[0085] (6) A surgical instrument according to any one of claims 1 to 5, wherein the electrical circuit further comprises a voltage-controlled current source (VCCS) circuit. (7) The surgical instrument of claim 6, wherein the electrical circuit is further configured to convert the electrical signal into a current-limiting signal using the VCCS circuit. (8) The surgical instrument of any one of claims 1 to 7, wherein the electrical circuit further includes an operational amplifier, and the electrical circuit is further configured to buffer and amplify the electrical signal using the operational amplifier before returning the electrical signal from the second electrode to the microcontroller. (9) The surgical instrument of any one of claims 1 to 8, wherein the electrical circuit is further configured to extract and analyze at least one feature from the electrical signal, the at least one feature being a feature selected from the group consisting of an amplitude of the electrical signal and a phase shift of the electrical signal. (10) A surgical instrument according to any one of claims 1 to 9, wherein the electrical circuit is further configured to identify a current waveform and a voltage waveform associated with the electrical signal delivered to the biological material.

[0086] (11) A surgical instrument according to any one of claims 1 to 10, wherein the electrical circuit is configured to determine the electrical impedance based on the capacitive reactance and inductive reactance of the biological substance. (12) A surgical instrument according to any one of embodiments 1 to 11, wherein the first electrode and the second electrode are presented by the end effector. (13) A surgical instrument according to any one of claims 1 to 12, wherein the first electrode is presented by the end effector and the second electrode is located remotely from the end effector. (14) A surgical instrument according to any one of claims 1 to 13, wherein the end effector further comprises a staple cartridge removably coupled to the second jaw and having a plurality of staples, and the microcontroller is fixed to a body of the staple cartridge. (15) A surgical instrument according to any one of claims 1 to 14, wherein the microcontroller is disposed on an inner surface of one of the first jaw or the second jaw.

[0087] (16) A method of operating a surgical instrument having a first electrode and a second electrode and an end effector containing a microcontroller, the method comprising: (a) using the microcontroller to control delivery of an electrical signal to the first electrode, the first electrode configured to directly contact and deliver the electrical signal to the biological material clamped by the end effector; (b) receiving the electrical signal at the second electrode after the electrical signal has passed from the first electrode through the biological material; (c) determining, by the microcontroller, an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; and (d) based on the electrical impedance, (i) the presence of tissue in the biological material; (ii) the absence of tissue in the biological material; or (iii) determining by the microcontroller at least one of the characteristics of a tissue forming at least a portion of the biological material; A method comprising:

Claims

1. 1. A surgical instrument comprising: (a) an end effector configured to interact with biological matter in a patient, the end effector comprising: (i) a first jaw; (ii) a second jaw configured to cooperate with the first jaw to clamp the biological material; (iii) a first electrode positioned between the first jaw and the second jaw and configured to directly contact and deliver an electrical signal to the biological material; (b) a second electrode configured to receive the electrical signal from the first electrode; and (c) an electrical circuit contained within the end effector, the electrical circuit including a microcontroller; (i) controlling delivery of the electrical signal to the first electrode such that the electrical signal passes from the first electrode through the biological material to the second electrode; (ii) determining an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; (iii) based on the electrical impedance, (A) the presence of tissue in the biological material; (B) the absence of tissue in the biological material; or (C) a property of a tissue forming at least a portion of the biological material; and A surgical instrument comprising:

2. The surgical instrument of claim 1 , wherein the electrical circuitry is further configured to generate the electrical signal using the microcontroller, the electrical signal comprising a composite waveform.

3. The surgical instrument of claim 2 , wherein the composite waveform has a fixed single fundamental frequency.

4. The surgical instrument of claim 1 , wherein the electrical circuit further comprises a band pass filter (BPF).

5. The surgical instrument of claim 4, wherein the electrical circuit is configured to pass the composite waveform through the band pass filter before delivery to the first electrode.

6. The surgical instrument of claim 1 , wherein the electrical circuit further comprises a voltage controlled current source (VCCS) circuit.

7. The surgical instrument of claim 6, wherein the electrical circuitry is further configured to convert the electrical signal into a current-limited signal using the VCCS circuitry.

8. 10. The surgical instrument of claim 1, wherein the electrical circuit further includes an operational amplifier, the electrical circuit further configured to buffer and amplify the electrical signal using the operational amplifier before returning the electrical signal from the second electrode to the microcontroller.

9. 10. The surgical instrument of claim 1, wherein the electrical circuitry is further configured to extract and analyze at least one feature from the electrical signal, the at least one feature being a feature selected from the group consisting of an amplitude of the electrical signal and a phase shift of the electrical signal.

10. The surgical instrument of claim 1 , wherein the electrical circuitry is further configured to identify current and voltage waveforms associated with the electrical signal delivered to the biological material.

11. The surgical instrument of claim 1 , wherein the electrical circuit is configured to determine the electrical impedance based on capacitive and inductive reactances of the biological material.

12. The surgical instrument of claim 1 , wherein the first electrode and the second electrode are presented by the end effector.

13. The surgical instrument of claim 1 , wherein the first electrode is presented by the end effector and the second electrode is located remotely from the end effector.

14. 10. The surgical instrument of claim 1, wherein the end effector further comprises a staple cartridge removably coupled to the second jaw and having a plurality of staples, the microcontroller being fixed to a body of the staple cartridge.

15. The surgical instrument of claim 1 , wherein the microcontroller is disposed on an interior surface of one of the first jaw or the second jaw.

16. 1. A method of operating a surgical instrument having a first electrode and a second electrode and an end effector containing a microcontroller, the method comprising: (a) using the microcontroller to control delivery of an electrical signal to the first electrode, the first electrode configured to directly contact and deliver the electrical signal to the biological material clamped by the end effector; (b) receiving the electrical signal at the second electrode after the electrical signal has passed from the first electrode through the biological material; (c) determining, by the microcontroller, an electrical impedance associated with the biological material based on the electrical signal received by the second electrode; and (d) based on the electrical impedance, (i) the presence of tissue in the biological material; (ii) the absence of tissue in the biological material; or (iii) determining by the microcontroller at least one of a property of a tissue forming at least a portion of the biological material; A method comprising:

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