Medical devices with blood coagulation function

Abstract

The present invention is entitled "Medical device with coagulation effect". In one embodiment, a medical system includes a medical device, which includes: a slender shaft having a distal end; at least one cutting element, the at least one cutting element is disposed at the distal end of the shaft; a position tracking transducer, the position tracking transducer is disposed at the distal end of the shaft and is electrically insulated from the shaft and the at least one cutting element; and at least one metal coagulation electrode, the at least one metal coagulation electrode is at least partially disposed above the position tracking transducer, the position tracking transducer electrically isolates the at least one metal coagulation electrode from the shaft; a signal generator, the signal generator is coupled to apply current to the at least one metal coagulation electrode; and a processing circuit, the processing circuit is configured to receive a signal generated by the position tracking transducer and track the position of the distal end in response to the received signal.

Description

Technical Field

[0001] The present invention relates to medical devices and particularly, but not exclusively, to devices for performing coagulation. Background Art

[0002] In medical applications, tissue cutting may be performed using a razor or debridement, which often results in heavy bleeding. Coagulation in surgery may be performed by applying an electric current to the bleeding tissue. By way of example, U.S. Patent No. 5,810,809 to Rydell describes an arthroscopic instrument for debridement of tissue that includes an electrocautery electrode for applying hemostasis at the surgical site. The drive motor for the debridement instrument is placed away from the handle of the instrument, and the handle is electrically isolated from the drive motor and associated power source even when arthroscopic surgery is performed in saline.

[0003] U.S. Patent 8,702,702 to Edwards et al. describes a mechanical cutting device that utilizes mechanical (rotational) motion and suction to engage tissue and also applies cutting energy sufficient to vaporize the tissue. Rotation and suction are used to engage tissue (when the cutting windows of the inner blade and outer blade are aligned, the tissue is drawn into the cutting window), and then the cutting member is made to act as an electrode by applying an electrical cutting signal to it, so that the cutting member electrically cuts the tissue as the cutting members rotate relative to each other. The electrical cutting signal is applied only when the windows become aligned until the cutting of the tissue is completed. After the cutting windows become misaligned, the cutting signal is preferably stopped. When the cutting windows are misaligned, a coagulation signal may be provided to the cutting member so that the device acts as an electrocautery device.

[0004] U.S. Patent Publication 2014 / 0148729 to Schmitz et al. describes a method for removing at least a portion of a brain tumor that may first involve contacting a forward-facing tissue cutter disposed at a distal end of a tissue removal device with the brain tumor. The tissue removal device may include a shaft having a diameter of no greater than about 10 mm, and in some embodiments, the tissue cutter does not extend laterally beyond the diameter of the shaft. The method may then involve cutting tissue from the brain tumor using the tissue cutter. The method may then involve moving the cut tissue through a channel of the shaft in a direction from the distal end of the tissue removal device toward the proximal end of the device. Summary of the invention

[0005] According to an embodiment of the present disclosure, a medical system is provided, which includes a medical device, which includes: an elongated shaft having a distal end; at least one cutting element, which is disposed at the distal end of the shaft; a position tracking transducer, which is disposed at the distal end of the shaft and is electrically insulated from the shaft and the at least one cutting element; and at least one metal coagulation electrode, which is at least partially disposed above the position tracking transducer, and the position tracking transducer electrically isolates the at least one metal coagulation electrode from the shaft; a signal generator, which is coupled to apply current to the at least one metal coagulation electrode; and a processing circuit, which is configured to receive a signal generated by the position tracking transducer and track the position of the distal end in response to the received signal.

[0006] Additionally, in accordance with an embodiment of the present disclosure, the processing circuit is configured to control the signal generator to apply current to the at least one metallic coagulation electrode in response to actuating a cutting action by the at least one cutting element.

[0007] Furthermore, according to an embodiment of the present disclosure, the processing circuit is configured to control the signal generator to maintain the current applied to the at least one metal coagulation electrode for a period of time after the cutting action is stopped.

[0008] Additionally, according to an embodiment of the present disclosure, the at least one metal coagulation electrode includes a first metal coagulation electrode and a second metal coagulation electrode, wherein the signal generator is coupled to apply a current between the first metal coagulation electrode and the second metal coagulation electrode.

[0009] Furthermore, in accordance with an embodiment of the present disclosure, a signal generator is coupled to apply an electric current between the at least one metallic coagulation electrode and the at least one cutting element.

[0010] Additionally, in accordance with an embodiment of the present disclosure, a signal generator is coupled to apply an electric current between the at least one metal coagulation electrode and the at least one head surface electrode.

[0011] Additionally, in accordance with an embodiment of the present disclosure, at least one of the metal coagulation electrodes includes a metal ring wrapped around the shaft.

[0012] Additionally, in accordance with embodiments of the present disclosure, at least one metallic coagulation electrode covers at least 90% of the outwardly facing surface area of ​​the position tracking transducer.

[0013] Furthermore, according to an embodiment of the present disclosure, the position tracking transducer includes at least one coil.

[0014] In addition, according to an embodiment of the present disclosure, at least one coil is printed on the circuit board, and at least one coil is coated with an electrical insulating material.

[0015] In addition, according to an embodiment of the present disclosure, the medical device is configured for insertion into a body part of a living subject, and the system also includes a positioning pad having at least one magnetic field radiator configured to transmit an alternating magnetic field to an area where the body part is located, and at least one coil of the position tracking transducer is configured to detect at least a portion of the transmitted alternating magnetic field.

[0016] In addition, according to an embodiment of the present disclosure, a medical device is configured for insertion into a body part of a living subject, and the system also includes a display, and the processing circuit is configured to cause the display to present an image including a representation of at least a portion of the body part and a representation of at least a portion of the medical device inserted into the body part in response to the tracked position.

[0017] According to another embodiment of the present disclosure, a method for performing medical treatment using a medical device is also provided, the medical device comprising: an elongated shaft having a distal end; at least one cutting element, the at least one cutting element being disposed at the distal end of the shaft; a position tracking transducer, the position tracking transducer being disposed at the distal end of the shaft and being electrically insulated from the shaft and the at least one cutting element; and at least one metal coagulation electrode, the at least one metal coagulation electrode being at least partially disposed above the position tracking transducer, the position tracking transducer electrically isolating the at least one metal coagulation electrode from the shaft, the method comprising applying an electric current to the at least one metal coagulation electrode, receiving a signal generated by the position tracking transducer, and tracking the position of the distal end in response to the received signal.

[0018] Furthermore, in accordance with embodiments of the present disclosure, applying is performed in response to actuating a cutting action by at least one cutting element.

[0019] Additionally, according to an embodiment of the present disclosure, the method includes maintaining the current applied to the at least one metal coagulation electrode for a period of time after the cutting action is stopped.

[0020] Furthermore, according to an embodiment of the present disclosure, the at least one metal coagulation electrode includes a first metal coagulation electrode and a second metal coagulation electrode, wherein applying includes applying an electric current between the first metal coagulation electrode and the second metal coagulation electrode.

[0021] Additionally, in accordance with embodiments of the present disclosure, applying includes applying an electric current between the at least one metallic coagulation electrode and the at least one cutting element.

[0022] Furthermore, in accordance with an embodiment of the present disclosure, applying includes applying an electric current between at least one metal coagulation electrode and at least one head surface electrode.

[0023] Additionally, in accordance with an embodiment of the present disclosure, at least one of the metal coagulation electrodes includes a metal ring surrounding the shaft.

[0024] Furthermore, in accordance with an embodiment of the present disclosure, at least one metallic coagulation electrode covers at least 90% of the outwardly facing surface area of ​​the position tracking transducer.

[0025] Additionally, according to an embodiment of the present disclosure, the position tracking transducer includes at least one coil.

[0026] Furthermore, according to an embodiment of the present disclosure, at least one coil is printed on the circuit board, and at least one coil is coated with an electrical insulating material.

[0027] Additionally, according to an embodiment of the present disclosure, the medical device is configured for insertion into a body part of a living subject, the method further comprising transmitting an alternating magnetic field into an area where the body part is located, and detecting at least a portion of the transmitted alternating magnetic field by the at least one coil.

[0028] Furthermore, according to an embodiment of the present disclosure, the medical device is configured for insertion into a body part of a living subject, and the method further comprises causing a display to present an image including a representation of at least a portion of the body part and a representation of at least a portion of the medical device inserted into the body part in response to the tracked position. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be understood from the following detailed description in conjunction with the accompanying drawings, in which:

[0030] Figure 1 is a schematic diagram of a medical procedure system according to an embodiment of the present invention;

[0031] Figure 2 A schematic diagram of a magnetic field radiation component used in a medical procedure system according to an embodiment of the present invention;

[0032] Figure 3 For use Figure 1 A schematic diagram of a medical device in a system;

[0033] Figure 4 Shows Figure 3 Handles and interchangeable heads of medical devices;

[0034] Figure 5 Shows the settings in Figure 3 A transducer on a handle and an interchangeable head of a medical device;

[0035] Figure 6 To include Figure 5 A flowchart of exemplary steps in a method for calibrating a medical device;

[0036] Figure 7 To include Figure 1 A flowchart of exemplary steps in a method of operating a medical procedure system;

[0037] Figure 8 for Figure 1 A medical procedure system presenting a schematic diagram of an image of a body part and a representation of an interchangeable head into which the body part has been inserted;

[0038] Fig.9A and 9B A metal coagulation electrode is provided thereon Figure 5 Schematic diagram of an interchangeable head of a medical device;

[0039] Fig.10 According to an alternative embodiment of the present invention Figure 1 a block diagram of a portion of a console of a medical procedure system; and

[0040] Fig.11 To include Figure 1 A flow chart of exemplary steps in a coagulation method performed by a medical procedure system. DETAILED DESCRIPTION

[0041] Overview

[0042] As mentioned above, in medical applications, tissue cutting may be performed using a razor or debridement, which often results in heavy bleeding. Blood coagulation in surgery may be performed by applying an electrical current to the bleeding tissue.

[0043] Performing coagulation with a medical device may be complicated by the geometry and mechanical structure of the medical device. For example, if the medical device includes many conductive surfaces, the applied current may be limited due to the inherent short circuits caused by the metal surfaces. Adding additional non-conductive structures to the medical device may increase the bulk of the medical device too much.

[0044] Embodiments of the present invention provide a medical system including a medical device having: an elongated shaft having a distal end; at least one cutting element disposed at the distal end of the shaft; and a position tracking transducer disposed at the distal end of the shaft. The medical device is typically inserted into a body part of a living subject to cut tissue from the body part.

[0045] The processing circuit receives the signal generated by the position tracking transducer and tracks the position of the distal end in response to the received signal. The processing circuit also causes the display to present an image including a representation of at least a portion of the body part and a representation of at least a portion of the medical device inserted into the body part in response to the tracked position.

[0046] By way of example only, the position tracking transducer may include at least one coil.In some embodiments, the position tracking transducer may include two or more orthogonally positioned coils.

[0047] In some embodiments, a positioning pad having at least one magnetic field radiator transmits an alternating magnetic field into the area where the body part is located. The coil of the position tracking transducer detects at least a portion of the transmitted alternating magnetic field. The position of the distal end can then be tracked based on the signal output by the position tracking transducer. In other embodiments, the position of the distal end can be tracked using any suitable position tracking system (such as, but not limited to, current-based or ultrasound-based position tracking).

[0048] The coil may be printed on a printed circuit board, and the coil may be coated with an electrically insulating material. There are several advantages to using a PCB transducer. First, a PCB transducer is not affected by metal interference, which is important when the medical device includes metal components. Second, the PCB can be placed on the distal end of the elongated shaft in a very accurate orientation. Third, the PCB transducer is not a wound coil, but a printed coil, so that each PCB has substantially the same magnetic sensitivity. Therefore, based on the above advantages, a PCB transducer generally does not require calibration and does not require a controller (e.g., an EEPROM) that is generally too large to be disposed on the distal end.

[0049] The position tracking transducer is electrically isolated from the shaft and cutting element, for example by a PCB and a coating applied to the coil.

[0050] The medical device also includes at least one metallic coagulation electrode disposed at least partially over the position tracking transducer, the position tracking transducer electrically isolating the metallic coagulation electrode from the shaft.

[0051] In addition to the electrical isolation provided by the position tracking transducer between the metal coagulation electrode and the shaft, the metal coagulation electrode also provides a certain amount of electromagnetic shielding to the position tracking transducer. The above-mentioned positioning pads generally transmit magnetic fields at relatively low frequencies (e.g., about 20 KHz), while background radiation may be in the radio wave spectrum. The metal coagulation electrode helps to filter out higher radio wave spectrum frequencies from the frequencies detected by the position tracking transducer. This filtering is particularly beneficial when the signal output by the position tracking transducer is processed at high frequencies by an analog-to-digital converter.

[0052] In some embodiments, the metal coagulation electrode comprises one or more metal rings surrounding the shaft. In some embodiments, the metal coagulation electrode covers at least 90% of the outwardly facing surface area of ​​the position tracking transducer.

[0053] The system also includes a signal generator coupled to apply an electrical current to the metal coagulation electrode, which current may include direct current (DC) or near DC (e.g., low frequency, such as up to 20Khz by way of example only), which causes coagulation to be performed in the area of ​​the cutting element, thereby stopping or at least reducing bleeding caused by the cutting.

[0054] In some embodiments, the processing circuit controls the signal generator to apply an electrical current to the metal coagulation electrode in response to actuating a cutting action by the cutting element.

[0055] In the disclosed embodiment, the processing circuit controls the signal generator to maintain the current applied to the metal coagulation electrode for a period of time (eg, up to 3 seconds, or in some cases more than 3 seconds) after the cutting action has ceased.

[0056] In some embodiments, the metal coagulation electrode includes two coagulation electrodes (eg, two rings surrounding the shaft), and the signal generator is coupled to apply a current between the two metal coagulation electrodes.

[0057] In other embodiments, the signal generator is coupled to apply a current between the metal coagulation electrode and the cutting element. In still other embodiments, the signal generator is coupled to apply a current between the metal coagulation electrode and at least one head surface electrode.

[0058] System Description

[0059] Documents incorporated herein by reference are to be considered an integral part of this application, except that, to the extent any term is defined in these incorporated documents in a manner that contradicts a definition explicitly or implicitly made in this specification, only the definition in this specification shall prevail.

[0060] Turning now to the drawings, according to an embodiment of the present invention, reference is now made to Figure 1 , which is a schematic diagram of a medical procedure system 20, and reference Figure 2 , which is a schematic diagram of a magnetic field radiating component positioning pad 24 used in system 20. Medical procedure system 20 is typically used during an invasive and / or exploratory procedure on a patient 22's sinuses or another body part, such as the brain.

[0061] For this procedure, the component 24 can be positioned behind and / or around the head of the patient 22, for example, by fixing the magnetic field radiation component 24 to a chair 25 (or bed) on which the patient sits (or lies). The magnetic field radiation component 24 in the illustrated example includes five magnetic field radiators 26 fixed in a horseshoe-shaped frame, which is positioned under or around the patient 22 so that the magnetic field radiators 26 surround the head of the patient 22. Alternatively, a smaller or larger number of radiators 26 in various configurations can be used. The magnetic field radiator 26 is configured to radiate an alternating magnetic field at a corresponding frequency into an area 30 where a body part is located, which is adjacent to the magnetic field radiation component 24 and includes the head of the patient 22.

[0062] The alternating magnetic field induces signals in position tracking transducer 32 and position tracking transducer 36. Position tracking transducer 32 is shown as being disposed on medical device 28 so as to track the position of medical device 28. Position tracking transducer 36 is shown as being disposed on patient 22 (e.g., on the forehead of patient 22 or any other suitable body part) so as to track the position of patient 22 (e.g., to track the position of the head of patient 22) to compensate for movement of the patient relative to magnetic field radiating assembly 24. By way of example only, medical device 28 may include any one or more of the following: a probe for insertion into a body part, an endoscope, and / or a surgical tool such as an ENT tool, a suction tool, a minimally invasive instrument, or a razor.

[0063] The position of the distal end of the medical device 28 and the position of the patient 22 may be tracked using a tracking subsystem that tracks the position and orientation coordinates of a position tracking transducer 32 and a position tracking transducer 36 mounted at the distal end, respectively. The position tracking transducers 32, 36 are configured to output signals indicative of the positions of the transducers 32, 36, respectively. The signals are processed by the tracking subsystem running on processing circuitry 38 to track the position of the distal end of the medical device 28 and the position of the patient 22 over time. In an embodiment where the tracking subsystem is a magnetic tracking subsystem, the position tracking transducer 32 and / or the position tracking transducer 36 include at least one coil that is referenced to the position of the distal end of the medical device 28 and the patient 22. Figure 5 In other embodiments, the tracking subsystem can be an electrical-based tracking subsystem that uses multiple head surface electrodes (e.g., multiple instances of position tracking transducer 36) to track the position of medical device 28 based on signals emitted by at least one electrode of medical device 28 (included in position tracking transducer 32). The tracking subsystem can be implemented using any suitable position tracking subsystem, such as, but not limited to, an ultrasound-based tracking system, wherein position tracking transducer 32 includes at least one ultrasound transducer. Using the tracking subsystem, physician 54 advances the distal end of medical device 28 into a body part, as described in detail below.

[0064] In some embodiments, the medical device 28 is attached to and held by a robotic arm 40 that is configured to manipulate the medical device 28. The robotic arm 40 includes a plurality of robotic joints configured to control movement of the robotic arm 40 and manipulate the medical device 28. In other embodiments, the medical device 28 is held and manipulated by a physician 54.

[0065] As described in detail below, the position tracking transducer 32 is attached to the medical device 28, and determination of the position and orientation of the position tracking transducer 32 enables tracking of the position and orientation of the distal end 34 (or other location) of the medical device 28, which can be reversibly inserted into a body part of a patient 22 (a living subject).

[0066] Similarly, determination of the position and orientation of position tracking transducer 36 enables tracking of the position and orientation of a portion (e.g., the head) of patient 22. Position tracking transducer 36 is Figure 1 2 is shown as being disposed on the forehead of the patient 22. The position tracking transducer 36 may be disposed on any other suitable body part of the patient 22 in order to track the position / movement of the patient 22.

[0067] Systems for tracking an object inserted into a patient using a magnetic field radiator, such as magnetic field radiator 26, are described in U.S. Patent Publication No. 2016 / 0007842 to Govari et al., which is incorporated herein by reference. In addition, a magnetic field radiator manufactured by Biosense Webster (33 Technology Drive, Irvine, CA 92618 USA) is described in U.S. Patent Publication No. 2016 / 0007842 to Govari et al., which is incorporated herein by reference. The system uses a tracking system similar to that described herein to find the position and orientation of the coil in an area irradiated by a magnetic field.

[0068] The robotic arm 40 typically has its own robotic coordinate system. The robotic coordinate system is aligned with the magnetic coordinate system of the magnetic field radiator 26, or vice versa. Alignment of the robotic coordinate system with the magnetic coordinate system can be performed, for example, by moving the robotic arm 40 or a medical device 28 attached to the robotic arm 40 to one or more known positions of the magnetic field radiator 26, such as to a position on the magnetic field radiating assembly 24 or to a position tracking transducer 36 or to one or more other known positions on the patient 22. Once alignment of the robotic coordinate system with the magnetic coordinate system has been performed, the position in the magnetic coordinate system can be translated to the robotic coordinate system in order to properly manipulate the robotic arm 40.

[0069] The elements of the system 20, including the radiator 26, can be controlled by a processing circuit 38, which includes a processing unit in communication with one or more memories. Typically, the elements can be connected to the processing circuit 38 via a cable, for example, the radiator 26 can be connected to the processing circuit 38 via a cable 58. Alternatively or in addition, the elements can be coupled to the processing circuit 38 in a wireless manner. The processing circuit 38 can be installed in a console 50, which includes an operating control 51, which typically includes a keypad and / or a pointing device such as a mouse or trackball. The console 50 is also connected to other elements of the medical procedure system 20, such as the proximal end 52 of the medical device 28. The physician 54 interacts with the processing circuit 38 using the operating control 51 while performing the operation, and the processing circuit 38 can present the results generated by the system 20 on a display 56.

[0070] In some embodiments, prior to performing a medical procedure, a CT image of patient 22 is acquired. The CT image is stored in a memory (not shown) for subsequent retrieval by processing circuitry 38. Figure 1 , the display 56 is shown showing various views 59 of a previous CT scan (or other suitable scan) which can be used as an aid to the physician 54 in guiding the medical device 28 in the body part. The display screen 56 also shows an image 61 captured by a camera (not shown) of the medical device 28. The CT image can be registered with the magnetic coordinate system so that a representation of the medical device 28 can be displayed on the display 56 along with the CT image, such as by referring to FIG. Figure 7 and Figure 8 Described in more detail.

[0071] In implementation, some or all of these functions of processing circuit 38 may be combined in a single physical component, or alternatively, implemented using multiple physical components. These physical components may include hard-wired or programmable devices, or a combination of the two. In some embodiments, at least some of the functions of the processing circuit may be implemented by a programmable processor under the control of suitable software. The software may be downloaded to the device in electronic form via a network, for example. Alternatively or in addition thereto, the software may be stored in a tangible, non-transient computer-readable storage medium, such as an optical, magnetic or electronic memory.

[0072] See now Figure 3 , which is used for Figure 1 Schematic diagram of a medical device 28 in the system 20. The medical device 28 includes a handle 62 into which a plurality of different rigid interchangeable heads 64 can be individually and reversibly inserted. Figure 3 One of the interchangeable heads 64 is shown inserted into the handle 62. The other of the interchangeable heads 64 is shown in FIG. Figure 4 as described below. Figure 3The illustrated medical device 28 also includes an irrigation or drainage tube 66 .

[0073] Figure 3 The illustrated medical device 28 is shown before any position tracking transducers are added to the medical device 28. In fact, in some embodiments, the medical device 28 can be implemented using off-the-shelf medical devices that are commercially available without position tracking transducers or sensors and adding position tracking transducers at appropriate locations, as will be described below with reference to Figure 5 Description. For example, Bien The S120 handpiece and interchangeable reusable blades (available in a form without a position tracking transducer) can be adapted to provide the medical device 28 described below. In other embodiments, the medical device 28 can be implemented as a purpose-built medical device with an integral position tracking transducer.

[0074] See now Figure 4 , which shows Figure 3 The medical device 28 includes a handle 62 and a plurality of different interchangeable heads 64 . Figure 4 The illustrated handle 62 and interchangeable heads 64 are also shown without position tracking transducers. The interchangeable heads 64 differ from one another with respect to head shape and / or head size.

[0075] Each interchangeable head 64 includes a plastic proximal end 68 that is inserted into a socket 70 of the handle 62. The socket 70 of the handle 62 includes a plurality of rotational positions for inserting different rigid interchangeable heads 64. For example, using the S120 handpiece, the reusable blade can be inserted into eight different rotational positions. In some embodiments, the interchangeable head 64 can be inserted into the socket 70 in a single rotational position.

[0076] The handle 62 includes a plurality of rotational positions to which the different rigid interchangeable heads 64 will rotate. Thus, once one of the interchangeable heads 64 is inserted into the socket 70, the inserted interchangeable head 64 can be rotated to a plurality of rotational positions using the rotation adjustment gear 72. In other embodiments, the inserted interchangeable head 64 cannot be rotated to another position.

[0077] exist Figure 4 In the example of FIG. 5 , each of the interchangeable heads 64 is implemented with an elongated shaft 74 having a distal end 76, the interchangeable head including at least one cutting element 78 disposed at the distal end 76 of the elongated shaft 74. The cutting element 78 may include a shaving bar (e.g., a rough surface cylindrical or spherical element) or a shaving blade that rotates within the elongated shaft 74 or any other suitable cutting element.

[0078] See now Figure 5 , which shows the setting Figure 3 The medical device 28 of the present invention is provided with transducers 80, 82 on the handle 62 and the interchangeable head 64. The handle 62 has a handle position tracking transducer 80 disposed thereon. The handle position tracking transducer 80 may include a dual-axis or tri-axis transducer, which may be used to detect the position and orientation (including roll) of the handle 62. In some embodiments, the handle position tracking transducer 80 may include at least one coil, such as two or three orthogonally placed coils.

[0079] Each interchangeable head 64 includes a head position tracking transducer 82 disposed thereon, located at the distal end 76 of the elongated shaft 74 of the interchangeable head 64. The head position tracking transducer 82 is electrically insulated from the elongated shaft 74 and the cutting element 78. A wire extending from the head position tracking transducer 82 is secured to the elongated shaft 74 using, for example, a self-adhesive tape 75.

[0080] In some embodiments, the head position tracking transducer 82 of each interchangeable head 64 may include at least one coil. The head position tracking transducer 82 of each interchangeable head 64 may include a dual-axis transducer (e.g., including two orthogonally placed coils) that can be used to detect the position and orientation (including roll) of the interchangeable head 64. The head position tracking transducer 82 may be printed on one or two printed circuit boards. For example, two coils may be printed on one or two printed circuit boards that are connected to the distal end 76 of the elongated shaft 74 so that each of the coils is orthogonal to each other. Printing the coils on a printed circuit board provides a more compact and more standardized transducer than using a wound coil. The coils may be coated with an electrically insulating material.

[0081] The handle position tracking transducer 80 and the head position tracking transducer 82 of each interchangeable head 64 are configured to detect at least a portion of the alternating magnetic field transmitted by the magnetic field radiator 26 ( Figure 2 ).

[0082] Prior to inserting the elongated shaft 74 into the body part, at least some of the elongated shaft 74 may be disposed in a plastic biocompatible sleeve. In some embodiments, the sleeve may cover the elongated shaft 74 from the plastic proximal end 68 up to and including the head position tracking transducer 82.

[0083] The head position tracking transducers 82 are strategically placed on the interchangeable heads 64 so that when each interchangeable head 64 is individually inserted into the handle 62, the relative position between the head position tracking transducer 80 and the head position tracking transducer 82 of the inserted interchangeable head 64 uniquely identifies the inserted interchangeable head 64, regardless of the rotational position at which the interchangeable head 64 is inserted into the handle 62 and regardless of the rotational position to which the inserted interchangeable head 64 is rotated. The relative position may include: (i) a distance D between the handle position tracking transducer 80 and one of the head position tracking transducers 82; and / or (ii) a relative orientation (which may or may not include roll) between the handle position tracking transducer 80 and one of the head position tracking transducers 82.

[0084] Therefore, different corresponding heads among the interchangeable heads 64 have corresponding head position tracking transducers 82 positioned in different manners arranged thereon (on the distal end 76 of the corresponding head 64) so ​​that when different corresponding heads among the interchangeable heads 64 are inserted into the handle 62, the different corresponding head position tracking transducers 82 define different corresponding positions relative to the handle position tracking transducer 80.

[0085] See now Figure 6 , which includes Figure 5 Flowchart 90 of exemplary steps in a method of calibrating a medical device 28. See also Figure 5 One of the interchangeable heads 64 is inserted (block 92) into the handle 62. The processing circuit 38 is configured to operate the control 51 ( Figure 1 )) Receive (box 94) the user identification that has been inserted into the interchangeable head 64.

[0086] Processing circuit 38 ( Figure 1 ) is configured to receive (block 96) signals generated by the handle position tracking transducer 80 and signals generated by the corresponding head position tracking transducer 82 of the corresponding head in the interchangeable head 64 inserted into the handle 62. The processing circuit 38 is configured to calculate (block 98) the relative position between the handle position tracking transducer 80 and the head position tracking transducer 82 inserted into the interchangeable head 64 in response to the received signals. The calculated relative position may include: (i) a calculated distance D between the handle position tracking transducer 80 and the head position tracking transducer 82 inserted into the interchangeable head 64; and / or (ii) a calculated relative orientation (which may or may not include roll) between the handle position tracking transducer 80 and the head position tracking transducer 82 inserted into the interchangeable head 64.

[0087] The processing circuit 38 is configured (block 100) to associate the user identification of the inserted interchangeable head 64 with the calculated relative position (e.g., calculated distance and / or calculated relative orientation) to allow subsequent identification of the inserted interchangeable head 64 being reinserted into the handle in response to a new calculated relative position (e.g., new calculated distance and / or new calculated relative orientation) within a given tolerance of the calculated relative position (e.g., calculated distance and / or calculated relative orientation). The given tolerance may be any suitable value, for example, the given tolerance may be in the range of 0.1 mm to 5 mm and / or an angular orientation tolerance of up to 5 or 10%.

[0088] At decision block 102, processing circuit 38 causes display 56 to present a question asking the user whether there is another rotational position into which the interchangeable head 64 can be inserted or to which the inserted interchangeable head 64 can be rotated. The user provides a response via operating control 51 for reception by processing circuit 38. If the user responds that there is another rotational position (branch 104), the user rotates the inserted interchangeable head 64 (block 106) to the new rotational position, and the method continues with the steps of block 96. When the inserted interchangeable head 64 can be freely rotated relative to the handle 62, the user can indicate this to the response to the presented question at the step of block 102, and then continuously rotate the inserted interchangeable head 64, while repeating the steps of blocks 96 to 100 for different rotational positions of the inserted interchangeable head 64. If the user responds that there are no more rotational positions (branch 108), processing circuit 38 causes display 56 to present (block 110) a question asking the user whether there are more interchangeable heads 64 to be corrected. The user responds to this question. If there are more interchangeable heads 64 to be calibrated (branch 112), the current head is removed (box 114), and the new interchangeable head 64 is inserted in the step of box 92, and then the steps in the flowchart 90 described above are followed. If there are no more interchangeable heads 64 to be calibrated (branch 116), the method ends (box 118).

[0089] The above-described correction method may include an additional step of checking whether the calculated relative position between the handle position tracking transducer 80 and the head position tracking transducer 82 that has been inserted into the interchangeable head 64 is the same as or within a given tolerance as the previously calculated relative position between the handle position tracking transducer 80 and the head position tracking transducer 82 of another of the interchangeable heads 64. If the calculated relative position is the same as or within a given tolerance as the previously calculated relative position between the handle position tracking transducer 80 and the head position tracking transducer 82 of another of the interchangeable heads 64, the processing circuit 38 may cause the display 56 to present a message notifying the user that the current placement of the head position tracking transducer 82 should be changed.

[0090] The correction data is saved in a table for later use during operation of the system 20 and will be referenced Figure 7 Described below.

[0091] See now Figure 7 , which includes Figure 1 Flowchart 120 of exemplary steps in a method of operating the medical procedure system 20. Figure 5 The physician 54 inserts (block 122) one of the interchangeable heads 64 into the handle 62. The processing circuit 38 ( Figure 1 ) is configured to receive (block 124) signals generated by the handle position tracking transducer 80 and signals generated by the corresponding head position tracking transducer 82 of the corresponding head of the interchangeable heads 64 inserted into the handle. The processing circuit 38 is configured to calculate (block 126) the relative position (e.g., distance and / or orientation) between the handle position tracking transducer 80 and the head position tracking transducer 82 that has been inserted into the interchangeable heads 64 in response to the received signals. The processing circuit 38 is configured to identify (block 128) which of the interchangeable heads 64 is inserted into the handle in response to the calculated relative position (e.g., distance and / or orientation), and optionally to identify whether the interchangeable head 64 is correctly inserted into the handle 62 in response to the calculated relative position. The step of block 128 includes the sub-steps described below.

[0092] The processing circuit 38 is configured to compare the calculated relative position with the values ​​in the table of stored relative positions and associated interchangeable heads 64 (block 130). At decision block 132, the processing circuit 38 determines whether the table includes a value within a given tolerance of the calculated relative position. If no value in the table is within the given tolerance of the calculated relative position (branch 134), the processing circuit 38 may cause the display 56 to present (block 136) a message indicating that the interchangeable head 64 was not identified or was not properly inserted into the handle 62. The process then continues with the steps of block 122.

[0093] If there is a value in the table that is within a given tolerance of the calculated relative position (branch 138 ), the interchangeable head 64 is identified (box 140 ) as the interchangeable head 64 associated with the value in the table, and the inserted interchangeable head 64 is identified as being correctly inserted into the handle 62 .

[0094] The processing circuit 38 is configured to track (block 142) the position of the inserted interchangeable head 64 in response to at least some of the received signals. The signals used to track the position of the inserted interchangeable head 64 may be based on signals received from the handle position tracking transducer 80 and / or signals received from the head position tracking transducer 82 of the inserted interchangeable head 64. When the interchangeable head 64 may be, for example, using the gear 72 ( Figure 4) is freely rotated, typically tracking the position of the inserted interchangeable head 64 based at least on the signal received from the head position tracking transducer 82 of the inserted head 64.

[0095] See now Figure 8 , the reason for which Figure 1 Schematic diagram of a medical procedure system 20 presenting a representation 148 of a body part and an image 146 of a representation 150 of an inserted interchangeable head 64. See also Figure 5 and Figure 7 In response to the tracked position and the identified shape and size of the inserted interchangeable head 64, the processing circuit 38 is configured to cause the display 56 ( Figure 1 ) presents (block 144) an image 146 that includes a representation 148 of at least a portion of a body part and a representation 150 of at least a portion of the inserted interchangeable head 64 of the medical device 28 in the body part. Because the interchangeable head 64 is rigid, the representation 150 of the inserted interchangeable head 64 can be presented based on the location of a single point of the inserted interchangeable head 64 and the known shape and size of the inserted interchangeable head 64 that is identified. An indicator 152 on the representation 150 can also be used to indicate the cutting element 78.

[0096] In some embodiments, the present invention may be performed even if the inserted interchangeable head 64 is manually identified into the system 20 by the physician 54, or even if the medical device 28 does not have an interchangeable or removable head, and / or even if the head is not rigid, and / or even if the head includes multiple sensors that enable the representation 150 of the head 64 to be presented based on the multiple sensors and not necessarily based on the known size and shape of the head 64. Figure 7 The steps of blocks 142 and 144 are described below.

[0097] See now Fig.9A and 9B , which has a metal coagulation electrode 154 disposed thereon Figure 5 Schematic diagram of an interchangeable head 64 of a medical device 28. In some embodiments, the interchangeable head 64 includes at least one metal coagulation electrode 154 ( Figure 5 ), the position tracking transducer electrically isolates the metal coagulation electrode 154 from the elongated shaft 74. In some embodiments, such as Fig.9A As shown, the metal coagulation electrode 154 is a single metal ring surrounding the elongated shaft 74. In other embodiments, such as Fig. 9BAs shown, the metal coagulation electrode 154 includes two metal coagulation electrodes, such as two metal rings (coaxially) surrounding the elongated shaft 74. In some embodiments, the metal coagulation electrode 154 provides electromagnetic shielding, as discussed in the overview section above. In some embodiments, the metal coagulation electrode 154 covers at least 90% of the surface area of ​​the position tracking transducer 82 facing outward. Fig.9A and 9B Also shown is a diagram for attaching the metal coagulation electrode 154 to the console 50 ( Figure 1 ) are connected together. The connector 156 can be covered by a plastic biocompatible sheath during use. The sheath typically does not cover the metal coagulation electrode 154. In some embodiments, the sheath can partially cover the metal coagulation electrode 154. The connector 156 extending from the metal coagulation electrode 154 is fixed to the elongated shaft 74, for example, using a self-adhesive tape 75.

[0098] It should be noted that the present invention may be implemented even if the medical device 28 does not include an interchangeable head or even if the head is deflectable. FIG. 9A to FIG. 11 The disclosed content.

[0099] See now Fig.10 , which is an alternative embodiment of the present invention Figure 1 1 is a block diagram of a portion of a console 50 of a medical procedure system 20. In addition to the processing circuit 38, the console 50 also includes a signal generator 158. The signal generator 158 is coupled to apply a current to the Fig.9A or the metal coagulation electrode 154 of 9B. The current is typically direct current (DC) or near DC (ie, low frequency alternating current (AC), such as up to 20 KHz by way of example only), as discussed in more detail above in the Overview section.

[0100] See now Fig.11 , which includes Figure 1 Flowchart 160 of exemplary steps in a coagulation method performed by the medical procedure system 20 .

[0101] The processing circuit 38 is configured to receive (block 162) a user input, such as via the operating controls 51, to initiate a cutting action of the medical instrument 28. The processing circuit 38 is configured to actuate (block 164) the cutting element 78 ( Figure 5) actuates a cutting action. In some embodiments, the cutting action can be initiated by pressing a switch (not shown) on the handle 62. The processing circuit 38 is configured to control (block 166) the signal generator 158 to apply current to the metal coagulation electrode 154 in response to the actuation of the cutting action by the cutting element 78. In some embodiments, the processing circuit 38 is configured to control (block 168) the signal generator 158 to maintain the current applied to the metal coagulation electrode 154 for a period of time (e.g., up to 3 seconds or more) after the cutting action is stopped.

[0102] When the metal coagulation electrode 154 includes two metal coagulation electrodes, the signal generator 158 is coupled to apply a current between the two metal coagulation electrodes 154. In some embodiments, the signal generator 158 is coupled to apply a current between the metal coagulation electrode 154 and the cutting element 78 ( Figure 5 ). In other embodiments, the signal generator 158 is coupled to apply a current between the metal coagulation electrode 154 and at least one head surface electrode. In some embodiments, the position tracking transducer 36 may include a head surface electrode.

[0103] For the sake of clarity, various features of the present invention described in the context of independent embodiments may also be provided in combination in a single embodiment. Conversely, for the sake of simplicity, various features of the present invention described in the context of a single embodiment may also be provided individually or in any suitable sub-combination.

[0104] The above embodiments are cited by way of example, and the present invention is not limited by what is specifically shown and described above. On the contrary, the scope of the present invention includes combinations and sub-combinations of the various features described above, as well as variations and modifications thereof, which should occur to those skilled in the art when reading the above description, and which are not disclosed in the prior art.

Claims

1. A medical system comprising: Medical devices, including: an elongated shaft having a distal end; at least one cutting element disposed at a distal end of the shaft; a position tracking transducer disposed at the distal end of the shaft and electrically isolated from the shaft and the at least one cutting element; and at least one metallic coagulation electrode, the at least one metallic coagulation electrode being disposed at least partially above the position tracking transducer, the position tracking transducer electrically isolating the at least one metallic coagulation electrode from the shaft; a signal generator coupled to apply an electric current to the at least one metallic coagulation electrode; and A processing circuit, the processing circuit being configured to: receiving a signal generated by the position tracking transducer; and In response to the received signal, the position of the distal end is tracked.

2. The system of claim 1, wherein the processing circuit is configured to control the signal generator to apply the current to the at least one metallic coagulation electrode in response to actuating a cutting action by the at least one cutting element.

3. The system of claim 2, wherein the processing circuit is configured to control the signal generator to maintain the current applied to the at least one metal coagulation electrode for a period of time after the cutting action is stopped.

4. The system of claim 1, wherein the at least one metallic coagulation electrode comprises a first metallic coagulation electrode and a second metallic coagulation electrode, wherein the signal generator is coupled to apply the current between the first metallic coagulation electrode and the second metallic coagulation electrode.

5. The system of claim 1, wherein the signal generator is coupled to apply the current between the at least one metallic coagulation electrode and the at least one cutting element.

6. The system of claim 1, wherein the signal generator is coupled to apply the current between the at least one metal coagulation electrode and at least one head surface electrode.

7. The system of claim 1, wherein the at least one metal coagulation electrode comprises a metal ring surrounding the shaft.

8. The system of claim 1, wherein the at least one metallic coagulation electrode covers at least 90% of an outwardly facing surface area of ​​the position tracking transducer.

9. The system of claim 1, wherein the position tracking transducer comprises at least one coil.

10. The system of claim 9, wherein the at least one coil is printed on a circuit board, the at least one coil being coated with an electrically insulating material.

11. A system according to claim 9, wherein the medical device is configured for insertion into a body part of a living subject, the system further comprising a positioning pad having at least one magnetic field radiator configured to transmit an alternating magnetic field into an area where the body part is located, and the at least one coil of the position tracking transducer is configured to detect at least a portion of the transmitted alternating magnetic field.

12. A system according to claim 1, wherein the medical device is configured for insertion into a body part of a living subject, the system further comprising a display, the processing circuit being configured to cause the display to present an image including a representation of at least a portion of the body part and a representation of at least a portion of the medical device inserted into the body part in response to the tracked position.

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