Systems and methods for wireless location integration - Patents.com

Abstract

A wireless location system including a pad with an excitation coil and a sensor coil, and a tool or surgical robot including a wireless tag configured to generate a signal in response to a magnetic field generated by the excitation coil. The signal is detected by the sensor coil, and a processor is configured to determine the location of the tool. The present disclosure relates to systems, devices, assemblies, and methods for integrating wirelessly locating marker tags into surgical and medical procedures. The systems, devices, assemblies, and methods find use in a variety of applications, including integration with surgical robot assemblies.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 189,394, filed May 17, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to systems, devices, assemblies, and methods for integrating wireless locating marker tags into surgical and medical procedures. The systems, devices, assemblies, and methods find use in a variety of applications, including integration with surgical robotic assemblies. [Background technology]

[0003] A common and serious challenge for many medical procedures is the precise location of the treatment area. For example, the location of a lesion, such as a tumor, that will undergo treatment, including surgical resection, continues to present a challenge to the medical community. Existing systems are expensive, complex, time consuming, and often uncomfortable for the patient.

[0004] Such problems are illustrated by the conventional surgical treatment of pulmonary nodules. Pulmonary nodules can be difficult to locate in conventional open surgery or thoracoscopy; in some cases, hook wires, injections of visible dyes, or radioisotopes are placed in or around the nodule in an attempt to improve localization prior to removal. This procedure usually occurs in a computed tomography (CT) facility prior to removal of the nodule. The patient is then transported to a surgical unit where the surgeon cuts wires, uses radioisotope detectors, or uses visual landmarks to locate and remove the nodule.

[0005] Similar types of procedures are performed to locate pulmonary nodules prior to resection. In some cases where pulmonary nodules may be difficult to locate in traditional open surgery or thoracoscopy, hook wires, injections of visible dyes, or radioisotopes are placed in or around the nodule in an attempt to improve localization prior to removal. This procedure usually occurs in a CT facility prior to removal of the nodule. The patient is then transported to a surgical unit where the surgeon cuts wires, uses radioisotope detectors, or uses visual landmarks to locate and remove the nodule.

[0006] In addition, tools used during medical procedures are also difficult to locate. For example, the location of a handheld tool utilized by a surgeon may not be known other than intuitively by the surgeon. Any wired location sensor adds to the number of wires, tubes, etc. extending from the handheld tool, thereby reducing the maneuverability of the tool.

[0007] Many other medical devices and procedures may benefit from improved tissue and tool localization. These include any procedure or test that is degraded by any bodily motion, such as cardiac motion, respiratory motion, motion caused by the musculoskeletal system, or gastrointestinal / urinary system motion. Examples of these include external beam radiation therapy, brachytherapy seed placement, imaging tests including, but not limited to, CT, MRI, fluoroscopy, ultrasound, and nuclear medicine, biopsies performed in any manner, endoscopy, laparoscopic, thoracoscopic surgery, and open surgical procedures.

[0008] The environment surrounding a patient during a medical procedure presents unique challenges to any wireless location system. For example, an operating room or doctor's office contains a variety of active sources of electromagnetic noise (e.g., overhead lighting, televisions, etc.) and reactive sources of electromagnetic noise that respond to wireless excitation signals. In other words, other equipment may transmit noise that interferes with the wireless location system. Examples include (a) active external noise caused by other electronic equipment broadcasting within the same frequency range used by the wireless location system, and (b) extraneous RFID noise. Extraneous RFID noise is created when the wireless location system energizes RFID tags that are not intended or designed to be part of the wireless location system, triggering these extraneous tags to respond with signals within the same frequency range used.

[0009] Another challenge arises with changing environmental materials. The environment may also contain various magnetic, ferromagnetic, or metallic objects that may distort the magnetic field generated and utilized by the wireless location system. Eddy currents are generated in conductors in response to the incident oscillating magnetic field, producing fields with opposing phases, which in effect produce secondary signal sources. The strength of the secondary sources depends on the magnetic vector coupling between the primary emitter and the metallic environment, which can be complex and difficult to model. For example, an operating room may include beds on which a patient is supported, and different beds will affect the magnetic field differently. In another example, an operating room with a surgical robot may include various robotically controlled appendages or arms that may interfere with or modify the electromagnetic field.

[0010] Improved systems and methods are needed for tissue and tool localization for medical procedures performed in a variety of environments. Summary of the Invention [Means for solving the problem]

[0011] The present disclosure provides, in one aspect, a wireless location system comprising a pad including an excitation coil and a sensor coil, and a tool including a wireless tag configured to generate a signal in response to a magnetic field generated by the excitation coil, the signal being detected by the sensor coil, and the system further includes a processor configured to determine a location of the tool based on the signal detected by the sensor coil.

[0012] In some embodiments, the tool is one of a camera, an ultrasound probe, an electrical impedance probe, an optical probe, a microforce probe, an electrocautery tool, a needle, a swallowable capsule, a keypad, a stapler, a clamp, and a sponge.

[0013] In some embodiments, the wireless tag is a first wireless tag, the signal is a first signal, and the system further includes a second wireless tag coupled to the patient's tissue and configured to generate a second signal in response to the magnetic field generated by the excitation coil.

[0014] In some embodiments, the processor is configured to determine a location of the tool relative to the second wireless tag.

[0015] In some embodiments, the tissue to which the second wireless tag is coupled is one of lung tissue, bone tissue, soft tissue, and an artery.

[0016] In some embodiments, the processor is further configured to determine an orientation of the tool.

[0017] The present disclosure provides, in one aspect, a wireless location system comprising a surgical robot assembly including a robotic arm, a camera, and a tool coupled to the robotic arm. The system further includes a pad including an excitation coil and a sensor coil. The system further includes a first wireless tag coupled to a portion of the surgical robot assembly. The first wireless tag is configured to generate a first signal in response to a magnetic field generated by the excitation coil, the first signal being detected by the sensor coil. The system further includes a second wireless tag coupled to tissue of a patient, the second wireless tag configured to generate a second signal in response to a magnetic field generated by the excitation coil. The second signal is detected by the sensor coil. The system further includes a processor configured to determine locations of the first wireless tag and the second wireless tag based on the first signal and the second signal detected by the sensor coil.

[0018] In some embodiments, the first wireless tag is coupled to a camera.

[0019] In some embodiments, the first wireless tag is coupled to a robotic arm.

[0020] In some embodiments, the sensor coil is a first sensor coil and the system further includes a second sensor coil coupled to the robot arm.

[0021] In some embodiments, the system further includes a movable object including a third wireless tag, which is moved to various positions and detected by the camera to align the field of view of the camera.

[0022] In some embodiments, the movable object includes an outer shell and an inner sphere movable relative to the outer shell. A third wireless tag is positioned within the inner sphere.

[0023] In some embodiments, the inner sphere includes a weighted portion to orient the sphere in a default orientation relative to gravity.

[0024] In some embodiments, the surgical robotic assembly includes a control console, and the location of the first wireless tag and the location of the second wireless tag are displayed on the control console.

[0025] In one aspect, the present disclosure provides a pad comprising an excitation coil configured to generate a magnetic field, a sensor coil, an electrically conductive layer, and an electromagnetically permeable layer positioned between the excitation coil and the conductive layer.

[0026] In some embodiments, the electrically conductive layer is a metal and the electromagnetically permeable layer is ferrous.

[0027] In some embodiments, the electromagnetically permeable layer has a permeability in the range of 10 to 5,000.

[0028] In some embodiments, the excitation coil is a first excitation coil and the pad further includes a second excitation coil, a third excitation coil, and a fourth excitation coil positioned circumferentially around the center.

[0029] In some embodiments, the magnetic fields generated by the first excitation coil, the second excitation coil, the third excitation coil, and the fourth excitation coil comprise three orthogonal magnetic fields.

[0030] In some embodiments, the sensor coil is a first sensor coil and the pad further includes a second sensor coil, a third sensor coil, and a fourth sensor coil.

[0031] In some embodiments, the first sensor coil, the second sensor coil, the third sensor coil, and the fourth sensor coil are positioned circumferentially around the first excitation coil.

[0032] In some embodiments, the first sensor coil includes a first sensor axis, the third sensor coil includes a third sensor axis, and the first sensor axis is parallel to the third sensor axis, the second sensor coil includes a second sensor axis, and the fourth sensor coil includes a fourth sensor axis, and the second sensor axis is parallel to the fourth sensor axis.

[0033] In some embodiments, the first sensor axis is perpendicular to the second sensor axis.

[0034] In some embodiments, the first excitation coil includes an excitation coil axis perpendicular to the first sensor axis and the second sensor axis.

[0035] In some embodiments, the sensor coil detects wireless signals in response to a magnetic field generated by the excitation coil, and the pad is positioned between the patient and a bed supporting the patient.

[0036] The present disclosure provides, in one aspect, a wireless tag comprising an outer housing including an anchor, the anchor configured to be anchored within tissue of a patient.

[0037] In some embodiments, the anchor is self-deploying.

[0038] In some embodiments, the anchor is a spiral.

[0039] In some embodiments, the anchor is a stent.

[0040] In some embodiments, the anchor extends radially outward from the longitudinal axis of the outer housing.

[0041] Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings. definition

[0042] As used herein, the terms "processor" and "central processing unit" or "CPU" are used interchangeably and refer to a device capable of reading a program from a computer memory (e.g., a ROM or other computer memory) and performing a set of steps in accordance with the program. As used herein, the term "processor" (e.g., a microprocessor, microcontroller, processing unit, or other suitable programmable device) may include, among other things, a control unit, an arithmetic logic unit ("ALC"), and multiple registers, and may be implemented using known computer architectures (e.g., modified Harvard architecture, von Neumann architecture, etc.). In some embodiments, a processor may be configured to communicate in an independent and / or distributed environment, and may be configured to communicate via wired or wireless communication with other processors, and may be configured to operate on one or more processor-controlled devices, such one or more processors may be similar or different devices.

[0043] As used herein, the term "memory" refers to any memory storage, non-transitory computer readable medium. Memory can include, for example, a program storage area and a data storage area. The program storage area and the data storage area can include a combination of different types of memory, such as ROM, RAM (e.g., DRAM, SDRAM, etc.), EEPROM, flash memory, hard disk, SD card, or other suitable magnetic, optical, physical, or electronic memory devices. A processor is connected to the memory and can execute software instructions, which can be stored in the RAM of the memory (e.g., during execution), the ROM of the memory (e.g., on a substantially permanent basis), or in another memory or another non-transitory computer readable medium, such as a disk. In some embodiments, the memory includes one or more processor-readable and accessible memory elements and / or components that can be internal to the processor-controlled device or external to the processor-controlled device and can be accessed via a wired or wireless network. Software included in the implementation of the methods disclosed herein can be stored in the memory. Software includes, for example, firmware, one or more applications, program data, filters, rules, one or more program modules, and other executable instructions. For example, a processor can be configured to read from a memory and execute instructions related to, among other things, the processes and methods described herein.

[0044] As used herein, the term "computer-readable medium" refers to any device or system for storing and providing information (e.g., data and instructions) to a computer processor. Examples of computer-readable media include, but are not limited to, DVDs, CDs, hard disk drives, magnetic tapes, and servers for streaming media over a network, whether local or remote (e.g., cloud-based).

[0045] "About" and "approximately" are used to provide flexibility to the numerical range endpoints by understanding that a given value can be "slightly more" or "slightly less" the endpoints without affecting the desired result.

[0046] The term "coupled," as used herein, is defined as "connected," but not necessarily directly, and not necessarily mechanically. The term "coupled" should be understood to mean physically, magnetically, chemically, fluidly, electrically, or otherwise coupled, connected, or connected, and does not exclude the existence of intermediate elements between the elements that are coupled, unless specifically termed to the contrary.

[0047] As used herein, the term "in electronic communication" refers to electrical devices (e.g., computers, processors, etc.) that are configured to communicate with each other through direct or indirect signal transmission. Similarly, a computer that is configured to transmit information to another computer or device (e.g., through cables, wires, infrared signals, telephone lines, air waves, etc.) also communicates electronically with other computers or devices.

[0048] As used herein, the term "transmit" refers to the movement of information (e.g., data) from one place to another (e.g., from one device to another) using any suitable means.

[0049] As used herein, the term "network" generally refers to any suitable electronic network, including, but not limited to, a wide area network ("WAN") (e.g., a TCP / IP-based network), a local area network ("LAN"), a neighborhood area network ("NAN"), a home area network ("HAN"), or a personal area network ("PAN") employing any of a variety of communication protocols, such as Wi-Fi, Bluetooth, ZigBee, etc. In some embodiments, the network is a cellular network, such as, for example, a Global System for Mobile Communications ("GSM") network, a General Packet Radio System ("GPRS") network, an Evolution Data Optimized ("EV-DO") network, an Enhanced Data Rates for GSM Evolution ("EDGE") network, a 3GSM network, a 4GSM network, a 5G New Wireless, a Digital Enhanced Wireless Telecommunications ("DECT") network, a Digital AMPS ("IS-136 / TDMA") network, or an Integrated Digital Enhanced Network ("iDEN") network.

[0050] As used herein, the term "subject" or "patient" refers to any animal (e.g., mammal), including, but not limited to, humans, non-human primates, companion animals, livestock, equines, rodents, and the like, that will be the recipient of a particular treatment. Typically, the terms "subject" and "patient" are used interchangeably herein with reference to a human subject.

[0051] As used herein, the term "subject / patient suspected of having cancer" refers to a subject who exhibits one or more symptoms that indicate cancer (e.g., a noticeable lump or mass) or is being screened for cancer (e.g., during a routine check-up). A subject suspected of having cancer may also have one or more risk factors. A subject suspected of having cancer has generally not been tested for cancer. However, "subject suspected of having cancer" encompasses individuals who have received an initial diagnosis (e.g., a CT scan that shows a mass) but the stage of the cancer is not known. The term also includes people who have had cancer in the past (e.g., individuals in remission).

[0052] As used herein, the term "biopsy tissue" refers to a sample of tissue (e.g., breast tissue) that is removed from a subject for the purpose of determining whether the sample contains cancerous tissue. In some embodiments, biopsy tissue is obtained because a subject is suspected of having cancer. The biopsy tissue is then examined (e.g., by microscopic examination, i.e., by molecular testing) for the presence or absence of cancer.

[0053] As used herein, the term "sample" is used in its broadest sense. In one sense, it is meant to include specimens or cultures obtained from any source, as well as biological and environmental samples. Biological samples may be obtained from animals (including humans) and include fluids, solids, tissues, and gases. Biological samples include tissues, blood products such as plasma, serum, and the like. Such examples, however, are not to be construed as limiting the sample types applicable to the present invention.

[0054] As used herein, the terms "tag," "marker tag," "radio tag," or "SmartClip®" refer to a small, implantable marker that, when excited by the time-varying magnetic field of an exciter, will emit a "homing beacon" spectrum of frequencies that are received by a "sensor coil" or "witness coil" and used to determine its location. It is programmed to produce a unique spectrum, thus allowing multiple tags to be implanted and located simultaneously. [Brief description of the drawings]

[0055] [Figure 1] FIG. 1 is a top-view schematic diagram of a wireless location system including a tool to be wirelessly tracked in an operating room for a medical procedure.

[0056] [Diagram 2] FIG. 2 is a schematic diagram of a needle containing a wireless tag and a patch with the wireless tag coupled to a patient's skin.

[0057] [Figure 3A] FIG. 3A is a schematic diagram of a keypad and stylus with a wireless tag.

[0058] [Figure 3B] FIG. 3B is an illustration of a located probe and a located needle with visual markings.

[0059] [Figure 4] FIG. 4 is a top schematic view of a wireless localization system including a surgical robotic system that is wirelessly tracked in an operating room for a medical procedure.

[0060] [Diagram 5] FIG. 5 is a side schematic view of a robot arm with a radio tag and a sensor coil.

[0061] [Figure 6A]FIG. 6A is a schematic diagram of a movable object for aligning camera views.

[0062] [Figure 6B] FIG. 6B is a method for aligning a camera to a wireless location system.

[0063] [Figure 7] FIG. 7 is a side view of a radio frequency location tag including multiple tines.

[0064] [Figure 8] FIG. 8 is a perspective view of a wireless tag including a plurality of self-deploying tines.

[0065] [Figure 9] FIG. 9 is a perspective view of a wireless tag including an anchor.

[0066] [Figure 10] FIG. 10 is a perspective view of a wireless tag including an anchor.

[0067] [Figure 11] FIG. 11 is a schematic diagram of a pad that includes four excitation coils that generate three orthogonal magnetic fields.

[0068] [Figure 12] FIG. 12 is a perspective view of a cross section of a pad including an electromagnetically permeable layer and an electrically conductive layer.

[0069] [Figure 13] FIG. 13 is a top view of a pad that includes four excitation coils and twelve sensor coils. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0070] Before any embodiment is described in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings, as the invention is capable of other embodiments and of being practiced or of being carried out in various ways. Detailed Description

[0071] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. In case of conflict, the present document, including definitions, will control. Preferred methods and materials are described below, although methods and materials similar or comparable to those described herein can also be used in the practice or testing of this disclosure. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and are not intended to be limiting.

[0072] As used herein, the terms "comprising," "include," "having," "has," "can," "contain," and variations thereof, are intended to be open-ended transitional phrases, terms, or words that do not exclude the possibility of additional acts or structures. The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. The present disclosure also contemplates other embodiments that "comprising," "consisting of," and "consisting essentially of" the embodiments or elements presented herein, whether or not explicitly stated.

[0073] With respect to the recitation of numerical ranges herein, each intervening number therebetween, with the same degree of precision, is also expressly contemplated. For example, with respect to the range from 6 to 9, the numbers 7 and 8 are also contemplated, in addition to 6 and 9, and with respect to the range from 6.0 to 7.0, the numbers 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, and 7.0 are also expressly contemplated.

[0074] In the foregoing description of the preferred embodiment, specific terminology has been used for the sake of clarity. However, it is to be understood that the present invention is not intended to be limited to the specific terminology so selected, and each specific term includes all technical equivalents that operate in a similar manner and accomplish a similar technical purpose. Terms such as "top" and "bottom", "front" and "back", "inside" and "outside", "upper", "lower", "upper side", "lower", "vertical", "horizontal", "upright", and the like are used as words of convenience to provide points of reference.

[0075] Provided herein are systems, devices, assemblies, and methods for integrating remotely locating tags into medical procedures. Although this specification focuses on medical use in human tissue, it is understood that the systems and methods find broader use, including non-human use (e.g., in conjunction with non-human animals such as livestock, companion animals, wild animals, or any veterinary setting). For example, the systems may be used in environmental settings, agricultural settings, industrial settings, or the like. A. Wireless tool tracking applications

[0076] In addition to being located within human tissue, the tag can be integrated into tools to wirelessly track the location and orientation of tools utilized in various medical procedures. Referring to FIG. 1, a wireless location system 100 is shown diagrammatically within an operating room (i.e., doctor's office, surgical equipment, etc.) for a typical medical procedure. The wireless location system 100 includes a pad 104 positioned beneath the patient. In some embodiments, the pad 104 includes at least one excitation coil (e.g., an exciter) and at least one sensor coil (e.g., a witness station). A wireless tag 108 is coupled to the patient's tissue and configured to generate a wireless signal in response to a magnetic field generated by the excitation coil. In some embodiments, the wireless tag 108 is configured to generate multiple wireless signals (e.g., a first wireless signal and a second wireless signal) in response to a magnetic field generated by the excitation coil. As discussed further herein, the wireless tag 108 is coupled to tissue (e.g., lung tissue, bone tissue, soft tissue, artery, etc.) in response to a medical procedure. An example of such a wireless tag 108 is described in US patent application Ser. No. 15 / 113,703, which is incorporated herein by reference in its entirety.

[0077] 1, the tool 112 includes at least one wireless tag 116 configured to generate a wireless signal in response to a magnetic field generated by an excitation coil in the pad 104. Wireless signals from the wireless tag 116 in the tool 112 and the wireless tag 108 in / on the patient are detected by, for example, a sensor coil in the pad 104. As detailed herein, the tool 112 is, in some embodiments, a surgical tool with the wireless tag 116 embedded therein.

[0078] The processor 120 (shown in FIG. 1 as part of the wireless location console 124) is configured to determine the location of the tool 112 and the location of the targeted area within the patient based on signals from the wireless tags 108, 116, as measured by the sensor coils. As discussed further herein, the relative locations of the tag 108 and the tool 112 within the patient tissue are utilized to improve the outcome of the medical procedure. For example, the relative distance between the tag 108 and the tool 112 may be indicated visually (e.g., on the display 105) or by providing audio or haptic feedback to the user. In some embodiments, the system 100 tracks the locations of multiple wireless tags.

[0079] In the illustrated embodiment, the tool 112 includes two wireless tags 116 positioned along the longitudinal axis 113 of the tool 112 that determine the orientation of the tool 112 in addition to the position of the tool 112. In some embodiments, the tags 116 are positioned within the outer housing of the tool 112. In other embodiments, the tags 116 are positioned on the exterior surface of the tool 112.

[0080] Continuing with reference to Figure 1, the environment in which wireless location system 100 is located includes various active and reactive sources of electromagnetic noise. For example, the environment in Figure 1 includes overhead lighting 106A, anesthesia machine 106B, display 105, surgical bed 106C, and electrocautery generator 106D, each of which may affect the electromagnetic fields present around wireless location system 100. As described herein, wireless location system 100 effectively tracks (e.g., locates) multiple wireless tags in proximity to various active and reactive sources of electromagnetic noise.

[0081] In some embodiments, the tool 112 is a camera. For example, some medical procedures utilize cameras to visualize the treatment area, but wireless tags implanted in the patient are typically not visible in the camera view. The solution presented herein is a camera with an integrated wireless tag for tracking the location of the camera and a processor for determining a coordinate transformation from implant tracker coordinates to camera field of view coordinates. Thus, the location of the implanted tag (e.g., tag 108) can be superimposed on the camera view (e.g., display 105) presented to the user, thereby improving the user's identification of the tag from the camera's field of view.

[0082] To determine the coordinate transformation, an object of known geometry is simultaneously imaged with the camera and located with the wireless location system. To track the camera, a wireless tag (e.g., tag 116) is fixed to the camera and tracked with the wireless location system. To track the roll of the camera, or if the wireless tag cannot be coaxial with the camera, two wireless tags are utilized. Alignment of the camera can occur in two ways: the camera remains stationary and a moving object is tracked (see FIG. 6A), or a stationary object is aligned with the moving camera. In some embodiments, the camera is moved manually by the user. In other embodiments, the camera is moved by an actuator.

[0083] In some embodiments, the tool 112 is an ultrasound probe. Ultrasound can be used to interrogate tissue and determine the location of the target tissue, but imaging is two-dimensional and a separate probe must be used. The solution presented herein is to track the position and orientation of the ultrasound probe simultaneously with the location of the implanted tag (e.g., tag 108). Ultrasound images at many positions and orientations may be acquired. The ultrasound probe and the tool used to perform the surgical removal are then interchanged and also tracked. The ultrasound images are then reconstructed according to the position of the electrosurgical tool and corrected for any relative shift in the implant location. Furthermore, the ultrasound images are segmented by tissue type and a 3D model can be constructed and registered to the implant location. After enough images are constructed, the 3D model can be maintained relative to the implant location and used in live navigation.

[0084] In some embodiments, the tool 112 is an electrical impedance probe. It may be useful to measure the 3D contour of the patient's body, including any external surfaces and internal organs (i.e., to measure the geometry of the tissue to be excised). The solution presented herein utilizes an electrical impedance probe to detect when the electrical impedance probe contacts the patient's tissue. If the location of the probe tip is tracked, the geometry of any part of the patient can be obtained by moving the probe tip around the skin.

[0085] In some embodiments, the tracked probe provides ultrasound of the patient tissue that is used to determine the target location relative to a tag positioned on the skin surface (e.g., embedded in an adhesive material that is adhered to the patient's skin). Once the ultrasound is compartmentalized, direct feedback to the user can be provided regarding needle placement, insertion orientation, and depth of insertion. In some embodiments, a motorized needle guide is tracked and adjusted to ensure proper needle insertion.

[0086] In some embodiments, the tool 112 is an optical probe. While spectroscopy can be performed, for example, by illuminating tissue with broadband light and collecting the reflected light, tracking of the location of the data collection must be performed manually. The solution presented herein collects location and spectral data simultaneously, such that the location of anomalies or features of interest can be automatically collected and presented to the user.

[0087] Pulmonary surgeons need to have clear visibility of the tumor location during video-assisted thoracic surgery (VATS) and robot-assisted thoracic surgery (RATS) procedures. Surgeons attempt to position 2D or 3D cameras to define the viewpoint, and traditional video processing may overlay graphics and text onto the video feed provided by the user. However, video processing typically requires interconnection between systems by cables, software, and facility-specific configurations. The solution presented herein is a projected light that overlays graphics and text onto tissue in the camera field of view. Alternatively, a tracked probe in the camera view can be equipped with one or more controlled light sources.

[0088] A projected light implementation compatible with VATS and RATS procedures includes, in some embodiments, a robotically controlled laser pointer mounted near the camera, with two motion-controlled axial degrees of freedom allowing the system to constantly aim the laser at the wireless tag, thereby directly illuminating a location on the tissue surface between the camera and the wireless tag. In some embodiments, the distance from the tissue surface to the wireless tag is determined by touching a wirelessly tracked probe to the tissue at the illumination point, or by using a camera video feed to determine the location of the illumination point. In such embodiments, the camera is calibrated and tracked in the same reference frame as the wireless tag and the light projector. In some embodiments, the projected light and machine vision processing are configured for structured light projection to more accurately determine the tissue geometry. In some embodiments, rasterization is used to project other graphics and text. In some embodiments, the light projection technique has no moving parts. In some embodiments, high-power light is utilized to burn the tissue and create a durable mark on the tissue.

[0089] A tracked probe with a controlled light source compatible with VATS and RATS procedures includes, in some embodiments, a single light emitting diode (LED) attached to the tracked probe. In some embodiments, the brightness of the LED is controlled by the system based on the relative position and / or alignment of the probe and the wireless tag. For example, a user may manipulate the tracked probe until the user sees illumination in the camera view, and when the brightness is maximized, the tracked probe is pointed directly at the wireless tag. In other embodiments, a tracked probe with a controlled light source compatible with VATS and RATS procedures includes multiple LEDs arranged in a pattern. In some embodiments, the brightness of each LED is controlled by the system based on the relative position and / or alignment of the probe and the wireless tag. For example, a user may observe a pattern configured to guide them to the wireless tag. In some embodiments, a set of LEDs arranged in a plane are illuminated such that the location of the highest intensity corresponds to the location of the wireless tag.

[0090] In some embodiments, the tool 112 is a micro-force probe. The bite force of the robot can be easy to control, but there are also advantages to wirelessly monitor the bite force. In some cases, the robot jaws are configured to grasp an object, but there is no feedback on the amount of resistance they are experiencing. The solution presented here is a radio tag embedded in a small module with a wireless communication module and one or more sensors and mechanical interfaces for measuring and transmitting real-time data such as force, temperature, pressure, etc. In some embodiments, the tool 112 is a specialized tracked tool that deflects measurably through the angle between two radio tags, the deflection being related to the amount of force applied to what is captured in the jaws. Advantageously, no battery is required since the communication can be powered by an exciter via induction. In other words, the same exciter used for localization can also provide power to the micro-sensor. Thus, the size can be minimized. For example, the communications chip can be as small as about 2.5 mm by about 2.5 mm without an antenna. The probe data can be used, for example, to generate haptic feedback to the user.

[0091] In some embodiments, the tool 112 is an electrocautery multi-tool. Conventional electrocautery tools include various cords or tubes that must be assembled by the user. The solution presented herein is a single device with smoke capture, illumination, electrocautery, and tip localization. The solution consolidates multiple cords into one and eliminates the user assembly step. This is beneficial because the localization and electrocautery systems are coordinated so that interference is mitigated. Advantageously, better cutting energy can be delivered by more precisely controlling the waveform and by using low energy to detect when the tip contacts tissue. Additionally, low energy detection of the tip contacting tissue can be used to build a 3D model of the patient.

[0092] In some embodiments, tool 112 is an electrocautery tool accessory (e.g., collar, tip, etc.). Conventional electrocautery tools include a tip that is removable from a pen. The solution presented herein is an adapter for an electrocautery tool (e.g., a Bovie pen). In some embodiments, the adapter is a small wireless device that is attached to the electrocautery tool, such as a collar. In other embodiments, a locatable tip (i.e., a tip with a wireless tag embedded in the shaft) is provided such that the tip can be wirelessly tracked by a wireless location system.

[0093] In some embodiments, the tool 112 is a stapler. In lung applications, the cut is optimally performed perpendicular to the lung plane. The solution presented herein is a stapler that includes at least one wireless tag configured to define the plane in which the lung will be cut and the edge of the stapler. In some embodiments, the wireless tag is oriented perpendicular to the plane of interest, which aligns the unknown roll coordinates of the wireless tag anywhere on the plane.

[0094] In some embodiments, the tool 112 is a tracked clamp configured to traverse the lung and span the entire cut.

[0095] In some embodiments, the tool 112 is a needle utilized in a medical procedure. The solution presented herein includes a needle 200 with a wireless tag 202 (e.g., SmartClip®) in the upper shaft that can be tracked. With reference to FIG. 2, the needle 200 includes a wireless tag 202 that is coupled to the needle 200 for localization of the needle 200. In some embodiments, a patch 204 that includes a wireless tag 205 is positioned on the skin of the patient 201 to localize the skin surface (e.g., track the location of the skin surface). The known distance 203 between the wireless tag 202 and the tip 206 of the needle 200 is utilized to provide advantageous information. Thus, the insertion depth of the needle is tracked by the patch 204 that is coupled to the patient's skin near the intended puncture site. The position and orientation of the patch 204 will also allow the angle of the needle 200 relative to the patient 201 to be calculated. Alternatively, the patch 204 is eliminated and the depth of insertion is tracked by having the user indicate when the tip 206 of the needle 200 is at the skin surface 201 .

[0096] In some embodiments, the tool 112 is a capsule or pill that is swallowed by the patient. For example, a conventional capsule is swallowed by the patient to diagnose GI problems. The solution presented herein is a capsule with an integrated radio tag to provide wireless tracking of the capsule and increase the usefulness of the device. With an integrated radio tag, the capsule can be enabled to deliver medication therapy based on commands given via wireless communication. Medication therapy delivery can be disrupted by requesting a large pulse of energy from the exciter. The large pulse can physically alter the capsule between a medication therapy delivery inhibiting configuration and a medication therapy delivery permitting configuration. Additionally, capsules with an integrated tag can embed a radio tag on demand to mark tissue of interest.

[0097] In some embodiments, the tool 112 is a keypad and stylus (i.e., a sterile surgical interface). In surgery, a sterile user cannot touch a non-sterile user input device. Bringing in an additional wired device to serve as an input device requires additional sterile field management. Conventional wireless input devices are typically expensive and battery-requiring. The solution presented herein provides a keypad (i.e., a low-cost keypad) without electronic or digital communication with an embedded wireless tag that can be located. A stylus or electrocautery tool that can be located can touch the keypad that can be located.

[0098] Referring to FIG. 3A, a keypad 250 includes two wireless tags 251 and is located by a wireless location system (e.g., system 100). The system then determines which key on the keypad was touched by tracking the location of a tracked tool tip or stylus 252 relative to the keypad 250. In other words, the tracked tool tip 252 location is known and the button location is known relative to the wireless tag 251 in the keypad 250. Thus, the location system can detect the location of the tracked tool tip 252 and will register the button press by the tool tip 252 to its location relative to the keypad 250. In some embodiments, the keypad provides a mechanical response on each button that can be recognized by the location system as a "click" based on a characteristic movement of the tracked tool (e.g., a tracked stylus, a tracked electrocautery tool, etc.). In some embodiments, the keypad is located by positioning a stylus with a single wireless location tag on or above the keypad.

[0099] 3B, in some embodiments, the tool 112 is a localized probe 310 that can be grasped by a robotic arm or tool 326. The localized probe 310 includes a conical tip 314 and a wireless tag 318 that is positioned in a housing 322. In the illustrated embodiment, the housing 322 is graspable by the robotic arm or tool 326. The probe 310 further includes a stem 330 with indicia 334 (e.g., visual markings) that can be detected and tracked by a camera. In other words, the localized probe 310 is a small, wirelessly tracked probe that can be grasped by a robot or other instrument within the patient's body, which has a stem that acts as a visual reference. In some embodiments, the orientation of the probe 310 is constrained to define the orientation of the probe. In other words, the robotic arm 326 can be constrained to keep the probe 310 oriented vertically with the stem 330 pointing upward at all times.

[0100] 3B, in some embodiments, the tool 112 is a localized needle 350 that is graspable by a robotic arm or tool 352. The localized needle 350 includes a housing 354 with a wireless tag 358 and a needle portion 362 with indicia 366 (e.g., visual markings) that can be detected and tracked by a camera. In other words, the localized needle 350 includes an insertion depth dimension that is readable by the camera. Thus, in some embodiments, the localized probe is inserted into the patient organ until its tip is co-located with the embedded wireless tag to serve as a physical landmark that is visualized by the camera. In some embodiments, this can be sensed tactilely. B. Robot integration applications

[0101] As disclosed herein, wireless tags are integrated into robots and robotic devices utilized in various medical procedures. An example of such a robotic system is the Intuitive da Vinci system. An example of a computer-assisted teleoperated surgical system and method is disclosed in U.S. Patent No. 11,207,143, the entire contents of which are incorporated herein by reference. Unique challenges arise when attempting to integrate wireless location tags into a robotic environment.

[0102] For example, patient anatomy and pre-operative imaging are insufficient for many surgical interventions. Wired-only navigation systems rely on pre-operative imaging and other methods to register detected locations to the patient anatomy. As mentioned, some medical procedures utilize cameras, but radio frequency tags implanted within the patient are typically not visible within the camera view. The solution presented herein provides radio frequency tag localization in robotic applications. Precise localization of the implanted tag, co-registered to the surgeon's visual frame of reference, along with tool localization, can provide intuitive dimensional feedback essential for successful interventions such as extraction, ablation, drug delivery, etc.

[0103] Referring to FIG. 4, a wireless location system 400 is shown diagrammatically in an operating room (i.e., doctor's office, surgical equipment, etc.) for a typical medical procedure. The environment in which the wireless location system 400 is positioned includes various active and reactive sources of electromagnetic noise. For example, the environment in FIG. 4 includes overhead lighting 406A, an anesthesia machine 406B, and a surgical bed 406C, each of which may affect the electromagnetic field present around the wireless location system 400. The wireless location system 400 includes a pad 404 that is positioned beneath the patient. In some embodiments, the pad 404 includes at least one excitation coil and at least one sensor coil (e.g., a witness station). The wireless location system 400 includes a surgical robot assembly 408 (e.g., the da Vinci system developed by Intuitive). In the illustrated embodiment, the surgical robot assembly 408 includes a robotic arm 412, a camera 416, and a tool coupled to a distal end of the robotic arm 412. In some embodiments, the surgical robot assembly 408 includes a single robotic arm. In other embodiments, the surgical robot assembly 408 includes at least one robotic arm. In the illustrated embodiment, the surgical robot assembly 408 includes three robotic arms 412. In some embodiments, the surgical robot assembly 408 includes multiple cameras. As described in more detail herein, the wireless localization system 400 integrates the surgical robot assembly 408 and provides improved localization of portions of the surgical robot assembly 408 relative to a target area within a patient. For example, visualization of a wireless tag 422 embedded within the patient can be overlaid on the visualization and robot vision from the camera 416. In some embodiments, the surgical robot assembly includes a control console 430 where a surgeon 431 controls the robot, and the location of the wireless tag is displayed on the control console.In some embodiments, the control console 430 is in the same location (e.g., the room) as the surgical robot, while in other embodiments the control console 420 is in a different location (e.g., a remote location, an off-site location).

[0104] 4, a first wireless tag 418 is coupled to a portion of the surgical robot assembly 408 (e.g., a robotic arm) and a second wireless tag 422 is coupled to a target tissue of a patient. The first wireless tag 418 and the second wireless tag 422 are configured to generate wireless signals in response to a magnetic field generated by at least one excitation coil in the pad 404. The wireless signals from the tags 418 and 422 are detected by at least one sensor coil in the pad 404. The processor 426 then determines the locations of the first wireless tag 418 and the second wireless tag 422 based on the signals measured by the at least one sensor coil.

[0105] 5, in some embodiments, the robotic arms 500 each include two wireless tags 504 mounted along a longitudinal axis 506 aligned with a surgical tool mounted on the distal end of the arm. In some embodiments, a sensor coil 508 (similar to and / or in addition to the sensor coil in the patient pad 510) is coupled to the robotic arm 500 to improve sensing of the wireless tag signal, which may be positioned away from the patient pad 510. In the illustrated embodiment, the sensor coil 508 is positioned axially between the two wireless tags 504 along the longitudinal axis 506. In some embodiments, the sensor coil 508 is oriented orthogonal to the coil in the wireless tag 504.

[0106] One challenge of integrating wireless tags into robotic applications is to effectively use cameras to measure anatomical landmarks. The use of cameras to measure landmarks has drawbacks such as challenges with illumination, lack of clear reference marks, tissue changes compared to the time of imaging, presence of fluid, etc. The solution presented herein allows co-registration to be achieved by aligning the camera location with respect to a wireless tag mounted on the camera and by tracking an object that travels to a specific point in the camera's field of view. The wireless tag mounted on the camera is not mounted directly on the lens, so the relative positions of the wireless tag and the camera lens are aligned to improve localization. In some embodiments, field of view alignment is accomplished by moving the tracked object to the top right, bottom right, top left, and bottom left corners of the field of view when the camera's position is known. In some embodiments, the camera is calibrated by placing a first wireless tag at a known close distance (e.g., within about 50 mm) from the camera and obtaining the camera position, and then the orientation of the camera is determined by imaging a second wireless tag with the camera while the second wireless tag is farther away from the camera. The wireless location system can locate the magnetic center and direction of the longitudinal axis of the wireless tag, but not necessarily which end of the tag is which. In order to consistently co-register the camera view with the system coordinate system, additional degrees of freedom are required to be constrained.

[0107] Referring to FIG. 6A, a tracked object 600 for camera alignment is illustrated. The tracked object 600 includes a clear outer shell 605 and an inner sphere 606 that is freely movable relative to the outer shell 605. In some embodiments, the outer shell 605 is configured to be grasped or gripped by a robotic tool. A wireless tag 604 is positioned within the inner sphere 606. In the illustrated embodiment, a weighted portion 602 (e.g., a weighted bottom) uses gravity to ensure that the wireless tag 604 within the inner sphere 606 is "oriented" in a given direction (i.e., upward and away from the patient pad) at all times, thereby providing sufficient information to constrain the last degree of freedom. In other words, the inner sphere 606 includes the weighted portion 602 and orients the inner sphere 606 and the tag 604 in a default orientation relative to gravity. The inner sphere 606 further includes multiple segments 608 of different colors or shades of black and white that are detectable by the camera. In the illustrated embodiment, the plurality of segments 608 includes four different color segments. In some embodiments, the plurality of segments 608 includes eight different color segments. Thus, the movable tracked object 600, which includes the wireless tag 604, is moved to various positions and detected by the camera to align the camera's field of view.

[0108] In some embodiments, the wireless tag is cylindrical, and the roll about its longitudinal axis and the direction in which the tag is pointing are difficult to determine. The solution presented herein is to place the wireless tag in an asymmetrically loaded mount. The wireless tag in the mount creates an angle of about 20-70 degrees from a line extending between the mount's center of mass and the mount's axis of rotation. The asymmetric loading provides sufficient constraints on the tag orientation to allow for both roll orientation and pointing direction determination. In some embodiments, the mount is enclosed within an object having a known pattern (e.g., a plurality of segments 608). The known pattern is imaged using a camera, allowing the object to be simultaneously located using the camera and the wireless location system. Once simultaneously located, a general transformation between the wireless location system and the camera is determined.

[0109] If the camera position is not known, the four corners of the field of view can be measured at two different distances from the camera to determine the camera location. In some embodiments, the camera performs a set of predefined movements (e.g., spinning, moving forward, etc.). In other embodiments, the camera views the same point from different perspectives. In some embodiments, the camera alignment configurations can be saved and loaded as pre-set configurations.

[0110] Referring to FIG. 6B, a method 650 for aligning a camera to a wireless location system is disclosed. The method 650 includes a step 654 of providing a camera unit with a wireless tag mounted thereon. The method 650 also includes a step 658 of moving the located probe into contact with the camera unit. In other words, the step 658 includes abutting the located probe against the camera unit. The method 650 also includes a step 662 of positioning the located probe within the camera field of view. In some embodiments, the located probe position within the field of view is the same probe from step 658. In other embodiments, the located probe located within the field of view is different than the located probe used in step 658. The method 650 further includes a step 666 of calibrating the camera zoom utilizing an object of known size located within the camera field of view. In some embodiments, the calibration contour is displayed to a user and the camera zoom is adjusted until the object of known size is contained within the calibration contour. In one embodiment, a known object with a 10 cm diameter is positioned in the camera field of view and the zoom on the camera is adjusted until the object fits within the calibration contour on the display. Method 650 further includes a step 670 of displaying a dimensionally accurate augmented reality. In other words, in step 670, the camera field of view can be overlaid with a 3D interface. In some embodiments, two 3D interfaces are provided on separate video feeds, one for each eye, such that the localization interface is overlaid on top of the 3D camera interface. Thus, method 650 provides a calibration process for aligning the camera view to a wireless localization system that visualizes the locations of various wireless tags. In some embodiments, additional corrections are applied to account for different camera lens types (e.g., wide aperture lens adjustments).

[0111] Another challenge of integrating wireless tags into surgical robotic applications is that metal objects should be kept away from the detector or sensor coils because they create distortions in the electromagnetic field. In other words, surgical robots often include metal components (e.g., metal arms) that can distort the electromagnetic fields relied upon by wireless localization systems. The solution presented herein is to utilize various noise reduction and signal processing techniques. In some embodiments, the system utilizes phase-sensitive signal processing.

[0112] Another challenge of integrating wireless tags into surgical robotic applications is that attaching the wireless tag directly to a metal component (e.g., a robot arm) can degrade the signal transmitted by the wireless tag due to eddy currents induced in the metal. The solution presented herein includes a thin layer of highly permeable material (e.g., iron, manganese, zinc, silicon, aluminum, nickel, electric steel, cobalt iron, etc.) positioned between the antenna windings of the wireless tag and the metal. In some embodiments, the layer of highly permeable material is selected based on the frequency range of the signal transmitted by the wireless tag.

[0113] Another challenge of integrating wireless tags into surgical robotic applications is that range is limited by the ability to measure, and features of interest on the patient can often be located far from the pad. The solution presented herein is to embed a high gain detector (e.g., 508 in FIG. 5) orthogonal to the emitter to sense the wireless tag signal. The high gain detector is mounted on a robotic component (e.g., the robot arm) and the sensor can be moved in close proximity to the wireless tag.

[0114] Another challenge of integrating tags into surgical robotic applications is that small wireless tags respond to only one direction of the excited field, and in some embodiments, a robotic application will have multiple wireless location tags (i.e., clips, SmartClip®) being tracked. The solution presented herein utilizes pads that generate three orthogonal directions of magnetic excitation field. With reference to FIG. 11, an exciter pad 1102 is illustrated generating three mutually orthogonal electromagnetic fields (e.g., X, Y, and Z directional electromagnetic fields) directly above the pad 1102. With three orthogonal directions of magnetic excitation field, there is sufficient power transfer for the wireless tag regardless of the wireless tag orientation. The preferred field direction for any wireless tag can be determined by measuring the total power received by the sensing system and choosing the field direction with the maximum total power. If multiple tags need to be located, only those excited by the same field direction can be located simultaneously. All tags are located by proceeding through the minimum number of field directions that allow all wireless tags to be located in sequence. The amount of time it takes to change field direction is important. To minimize the time, solid-state transistors are used to change the field polarity (instead of or in addition to electromechanical repeaters). In some embodiments, electromechanical repeaters may take longer to switch than solid-state transistors, and electromechanical repeaters will generate noise when switching that must be attenuated outside of narrow bandwidth signal conditioning. An exemplary pad with excitation coil and sensor coil is described in U.S. Pat. No. 10,278,779, the entire contents of which are incorporated herein by reference.

[0115] In some embodiments, the surgical robot performs an automated intervention (e.g., a set of steps based on a detailed surgical plan for the robotic movements). Another challenge of integrating tags into robotic applications is that the automated intervention may be based on a detailed surgical plan for the robotic movements. The solution presented herein is an automated safety measure that is enhanced by monitoring the robotic movements by an independent processing system that compares the actual movements with the planned movements and generates a signal if the plan deviates beyond an allowed tolerance. A secondary signal is generated when the robotic movements are not being tracked. In other words, in some embodiments, a wireless tag is utilized to track the robotic component and double check that it is moving according to the plan. Thus, the wireless tag can wirelessly track the movements of the robotic components and may be utilized to provide additional safety measures or safety lockouts. C. General surgical applications

[0116] The solutions provided herein also have general surgical applications, including, but not limited to, preventing items from being left within a patient, bone modeling, and soft tissue modeling.

[0117] A common problem with surgical procedures occurs when items (e.g., surgical instruments, sponges, etc.) are left behind in a patient after a surgical procedure is completed. The solution presented herein embeds wireless tags into such items so that they can be tracked wirelessly. Conventional magnetic field wireless object tracking systems are not compatible with wireless tag location systems. As described herein, magnetic field wireless object tracking is integrated into the tag location system, reducing the amount of equipment required and / or reducing the amount of wireless interference. Items tagged with the tags are detectable with high assurance using the EnVisio® system. Large numbers of tags can be supported if location requirements are relaxed. In some embodiments, the system keeps a running count, tracking the number of items introduced into the general magnetic field area and reducing the number of times tagged items are left in the general magnetic field area (i.e., keeping a cumulative total of items in the environment).

[0118] Another challenge is that conventional robotic guided orthopedic systems rely on optical tracking of bones, which requires that the optical tracker be surgically embedded into the bone, and the system maintains a direct line of sight to the optical tracker. The solution presented herein embeds two or more wireless tags (i.e., SmartClip®) into the bone, and uses preoperative imaging and image segmentation to establish the bone geometry in a coordinate system defined by the two or more wireless tags. In some embodiments, during surgery, the bone is mounted on a motor-driven actuator (e.g., a robotic arm) controlled by software, and the bone interface includes a wireless tag excitation and sensing subsystem.

[0119] Another challenge is that pre-operative imaging is collected with soft tissues in different positions, orientations, and shapes, and then presented in the operating room for surgery. The solution presented herein is to embed two or more wireless tags in the patient's soft tissues and / or on the skin. Pre-operative imaging can be performed with the tags in fixed positions, and imaging can be imported to observe the new location and orientation of the tags. The 3D images are deformed according to a volume-preserving algorithm that matches the imaged tags to the live observed tags. In some embodiments, the volume-preserving algorithm is physics and physiology-based, which may incorporate tissue density, elasticity, deformation, etc. D. Radio tag deployment

[0120] The tag can be delivered into the soft tissue using a conventional plunger mechanism through a needle, catheter, etc. In some embodiments, additional mechanical features are added to anchor the wireless tag to the surrounding tissue. Anchoring the wireless tag is important, especially during tissue extraction that involves manipulation of the tissue. With reference to FIG. 7, a wireless location tag 702 is positioned within a housing 704 having at least one tine 706 formed at an axial end 708 of the housing 704. In the illustrated embodiment, the tine 706 extends along a longitudinal axis 712 of the tag 702. The tine 706 is configured to grip, anchor, or otherwise tether the wireless tag 702 to the surrounding tissue.

[0121] 8, the wireless tag 802 includes a housing 804 with self-deploying tines 806 that engage within surrounding tissue and prevent migration. In the illustrated embodiment, the tines 806 are radially biased relative to a longitudinal axis 810 of the tag 802 (housing 804). In some embodiments, the tines 806 are movable to a first position where the tines 806 are biased radially inward toward the longitudinal axis 810 (e.g., during deployment or delivery) and the tines 806 are movable to a second position where the tines 806 extend radially outward from the longitudinal axis 810 (e.g., deployed and in place). In other words, the tines 806 deploy radially outward when in place. In some embodiments, the tines 806 are used to anchor the wireless tag 802 to the patient's lungs.

[0122] 9, a wireless tag 902 includes a housing 904 with tines 908. In the illustrated embodiment, the tines 908 are spirals that extend in a plane 910 perpendicular to a longitudinal axis 912 of the tag 902. In some embodiments, the tines 908 are made from Nitinol. The tines 908 are movable between a first position in which the spiral tines 908 are biased radially inward toward the longitudinal axis 912 (e.g., compressed circumferentially to a deployed position) and a second position (e.g., a deployed position) in which the spiral tines 908 extend radially outward. In the illustrated embodiment, the spiral tines 908 remain in the plane 910 as the tines 908 move between the first and second positions.

[0123] 10, a wireless tag 1002 includes a housing 1004 with tines 1006. In the illustrated embodiment, the tines 1006 are expandable stents. E. Targeted Radiation Delivery

[0124] When delivering high energy radiation to the soft tissue of a patient, it is essential to position the target tissue at the intended location. Conventional techniques for determining the location for irradiation include the use of external landmarks (e.g., anatomy, tattoos) or X-ray-based imaging. Once in place, conventional techniques for detecting patient movement include monitoring external tags, monitoring patient breathing via airflow.

[0125] The solution presented herein provides direct localization with a tag implanted at or near the site targeted for radiation. When a wireless tag is implanted at the site where radiation is intended to be delivered, the patient is necessarily positioned so that the tag is at or near the focus of the targeted radiation system. Thus, the volume over which the wireless tag is placed is relatively small (e.g., 10 cm x 10 cm x 10 cm) compared to other procedures. The tag excitation and sensing elements should not overlap with the radiation, both to prevent beam deflection and also to prevent damage to the electronics. In some embodiments, it is advantageous to have the excitation and sensing elements in separate modules, so that the excitation field is much lower and electronic filters are sufficient to remove the excitation signal. In some embodiments, a Helmholtz coil configuration with an exciter in two locations with a wireless tag between the two may also be advantageous. In other embodiments, a single pad with both the exciter and the sensor is placed alongside the patient instead of under the patient during radiation treatment. F. Perioperative Imaging

[0126] Radiopaque materials used in RFID tag signal excitation and sensing can obscure patient characteristics when present between the imaging source and detector. In some procedures, a signal is provided when a wire, catheter, or similar device is at a location intravascularly relative to the implant.

[0127] The solution presented herein is a wireless tag that is positioned within a stent (e.g., a coronary vessel), for example, when it is desired to retrieve the stent. The solution also includes a wired emitter that is coupled to the outer wall of a catheter or similar device. The wired emitter provides sufficient magnetic field strength to power the wireless tag. A sensor or set of sensors, positioned outside the body, listens for wireless tag responses (indicating that the wired emitter is approaching a wireless tag). In some embodiments, signal conditioning on the sensor signal includes a notch or low-pass filter to block the excitation signal carried by the emitter. When a wireless tag is within range of the wired emitter, the radio frequency spectrum characteristics can be sensed.

[0128] Alternatively, the implant contains a magnet and the catheter contains a sensitive magnetometer. The present approach includes a "zeroing" procedure to reduce the effects of variations in the local magnetic field due to earth and nearby metallic components.

[0129] Alternatively, the tag includes a passive highly resonant LC circuit and the reflected signal on the emitter is monitored. Changes in the coupling between the wired emitter and the implant modify the reflected signal, the location where the reflected signal is most affected corresponds to the location of maximum coupling, and the geometry of the emitter and tag are tailored so that the location of maximum coupling corresponds to the signal relative to the location of the catheter within the vessel. G. Arterial Access

[0130] Obtaining arterial access can be difficult, especially for femoral access in either cardiac or leg interventions. The solution presented herein is a wireless tag that is positioned along the artery at the intended access location under ultrasound or imaging guidance. In some embodiments, the needle used for initial access is tracked with a wireless or wired beacon and then guided by the system for ideal placement and orientation. High accuracy reduces bleeding and shortens the time required to gain access. H. Different Environments

[0131] Complex magnetic permeability changes in the vicinity of the pad can affect the signal used to locate the beacon. For example, metallic (highly conductive) materials force the magnetic field to zero with induced currents acting as a signal source at the same frequency. Ferrous (highly permeable) materials are less common but also modify the field. The pads positioned under the patient are placed as close as possible to the bed, with large metal components. A mapping process is used to learn the effect of the bed on the field and eliminate its effect on the localization. However, different environments range from no metal to mounting the pad directly on the metal. The solution presented here allows the pads to be used in these various environments.

[0132] The first challenge comes from the large metal loops embedded in the bed, which can generate a counter magnetic field that effectively cancels the excitation field. The solution presented herein is to position an electrically conductive layer 1206 (e.g., a conductive plate) on the bottom of the pad 1202. The conductive plate 1206 acts as a shield and changes the permeability below the pad 1202 in the environment. With reference to FIG. 12, the conductive plate 1206 shapes the magnetic field (see arrows 1210) and contains the electromagnetic flux within the pad 1202. In some embodiments, the conductive plate is a metal. In some embodiments, the conductive layer is aluminum. In some embodiments, the conductive layer is mu-metal, copper, or stainless steel. In some embodiments, the electrically conductive layer is at least 20×10 6 Includes conductivity in siemens per meter (S / m).

[0133] The second challenge comes from the conductive layer, which affects the excitation field due to currents induced in the metal and the resulting opposing magnetic field. With reference to FIG. 12, the solution presented herein is a pad 1202 with a first layer 1204 of a highly electromagnetically permeable material and a second layer 1206 of an electrically conductive material (e.g., a conductive plate). In some embodiments, the first layer 1204 has an electromagnetic permeability in the range of about 10 to about 5,000. In some embodiments, the first layer 1204 is a ferrite core (e.g., an oxide made from iron, manganese, and zinc, i.e., manganese zinc ferrite). In some embodiments, the first layer 1204 is a composite material including iron, silicon, aluminum, and / or nickel (e.g., a powder core).

[0134] In the illustrated embodiment, the first layer 1204 is positioned between the multiple excitation coils 1212 and the second layer 1206. The electromagnetic field in the second layer 1206 is lower and the corresponding current is induced lower. In the illustrated embodiment, the permeable layer 1202 is positioned between the excitation coils 1212 and the conductive layer 1206. Thus, the pad 1202 includes a combination of materials that redirect and confine magnetic flux onto the bottom of the pad 1202, such that the pad 1202 is configured to operate efficiently on a variety of surgical beds (e.g., "bed independent").

[0135] In some embodiments, the excitation coil 1212 is encapsulated with a high thermal conductivity encapsulation material 1214 (e.g., epoxy). In some embodiments, the encapsulation material has a thermal conductivity greater than 1,000 W / Kelvin. In some embodiments, the encapsulation material has a heat capacity greater than 1,000 Joules / kg°C. In some embodiments, the encapsulation material 1214 has a dielectric strength of at least 400 volts / mil. In some embodiments, a ferrite material helps shape the magnetic field.

[0136] A third challenge arises because the presence of highly permeable materials distorts the magnetic field direction. Distortion of the magnetic field direction poses a challenge because for each state of the exciter that produces a different field direction, it is desirable to position the sensor at a location and orientation where the sensor is orthogonal to the excitation field. The distortion is more pronounced in multi-exciter systems, where the phase of the current is varied to change the primary directivity of the induced magnetic field. This effect results in large changes in the field direction in the plane of the exciters as the exciters are configured to produce different field directions (e.g., FIG. 11).

[0137] 13, the solution presented herein is a pad 1301 with excitation coils 1300A, 1300B, 1300C, 1300D and sensor coils 1304A-1304L arranged in a grid configuration. The sensor coils 1304A-1304L are placed at locations where there is minimal change in field direction in the plane of the exciter. In the illustrated embodiment, the sensor coils 1304A-1304L define sensor coil axes 1306A-1306L, respectively, and the excitation coils 1300A-1300D define excitation coil axes 1302A-1302D, respectively. In this grid configuration, all sensor coils 1304A-1304L are oriented parallel to the tangent of the adjacent excitation coils 1300A-1300D. For example, the sensor coil axes 1306A, 1306D, 1306F, and 1306C of the sensor coils 1304A, 1304D, 1304F, and 1304C are oriented parallel to a tangent to the excitation coil 1300A. In other words, the sensor coil axes 1306A, 1306D, 1306F, and 1306C do not intersect the excitation coil axis 1302A.

[0138] With continued reference to FIG. 13, four excitation coils 1300A-1300D are positioned circumferentially around the center 1312 of the pad. In the illustrated embodiment, the sensor axes 1306A, 1306B, 1306F, 1306G, 1306K, and 1306L are aligned in a first direction (e.g., X-direction) and the sensor axes 1306C, 1306D, 1306E, 1306H, 1306I, and 1306J are aligned in a second direction (e.g., Y-direction). In the illustrated embodiment, the first and second directions are perpendicular. In the illustrated embodiment, the exciter axes 1302A-1302D are aligned in a third direction (e.g., Z-direction) perpendicular to the plane of the drawing of FIG. 13. In the illustrated embodiment, the sensor coils 1304A-1304L are positioned in alignment with at least one of the excitation coils (in line with at least one of the exciter axes 1302A-1302D). For example, the sensor coils 1304A, 1304D, 1304F, and 1304C are positioned circumferentially around the excitation coil 1300A. In the illustrated embodiment, there are sensor coils 1304A-1304L positioned at the midpoints on each side of the excitation coils 1300A-1300D, respectively.

[0139] In some embodiments, the excitation coil is circular. In other embodiments, the excitation coil is rectangular or another suitable shape. In some embodiments, the electronics utilized for monitoring and control of the pad are positioned under a conductive shield (e.g., the conductive shield is positioned between the electronics and the excitation coil).

[0140] In the illustrated embodiment, the highly permeable material withstands high fields without saturating. In some embodiments, the internally induced fields that the highly permeable material can support are higher than the externally applied fields.

[0141] Various features and advantages are set forth in the following claims.

Claims

1. 1. A wireless location system comprising: a surgical robot assembly including a robotic arm, a camera, and a tool coupled to the robotic arm; a pad including an excitation coil and a sensor coil; a first wireless tag coupled to the robot arm of the surgical robot assembly, the first wireless tag configured to generate a first signal in response to a magnetic field generated by the excitation coil, the first signal being detected by the sensor coil; and a second wireless tag coupled to tissue of a patient, the second wireless tag configured to generate a second signal in response to the magnetic field generated by the excitation coil, the second signal being detected by the sensor coil; and a third wireless tag coupled to the camera of the surgical robot assembly, the third wireless tag configured to generate a third signal in response to the magnetic field generated by the excitation coil, the third signal being detected by the sensor coil; and a processor configured to determine locations of the first wireless tag, the second wireless tag, and the third wireless tag based on the first signal, the second signal, and the third signal detected by the sensor coil; A system comprising:

2. The system of claim 1 , wherein the sensor coil is a first sensor coil, the system further comprising a second sensor coil coupled to the robot arm.

3. The system of claim 1 further comprising a movable object including a fourth wireless tag, said movable object being moved to various positions and detected by said camera to align the field of view of said camera.

4. The system of claim 3 , wherein the movable object includes an outer shell and an inner sphere movable relative to the outer shell, and the fourth wireless tag is positioned within the inner sphere.

5. The system of claim 4 , wherein the inner sphere includes a weighted portion to orient the sphere in a default orientation with respect to gravity.

6. The system of claim 1 , wherein the surgical robot assembly includes a control console, and the location of the first wireless tag and the location of the second wireless tag are displayed on the control console.

7. The system described in claim 6, wherein the location of the first wireless tag and the location of the second wireless tag are overlaid on the field of view of the camera.

8. The system described in claim 1, wherein the robotic arm is one of a plurality of robotic arms.

9. The system described in claim 1, further comprising a fourth wireless tag coupled to the robotic arm, the first wireless tag and the fourth wireless tag being mounted along a longitudinal axis of the robotic arm.

10. The system described in claim 9, wherein the sensor coil is a first sensor coil, and the system further includes a second sensor coil coupled to the robot arm, and the second sensor coil is positioned between the first wireless tag and the fourth wireless tag.

11. The system described in claim 10, wherein the second sensor coil is oriented orthogonal to a first coil in the first wireless tag and a fourth coil in the fourth wireless tag.

12. The system described in claim 1, wherein the first wireless tag includes a layer of material positioned between a winding and the robot arm.

13. The system of claim 12, wherein the material layer is iron, manganese, zinc, silicon, aluminum, nickel, electrical steel, or cobalt iron.

14. The system of claim 1, wherein the determined location of the first radio tag is compared to a planned movement of the robotic arm.

15. The system of claim 1, wherein the second wireless tag has an outer housing including an anchor, the anchor configured to be secured within the tissue of the patient, the anchor extending radially outward from a longitudinal axis of the outer housing.

16. The system of claim 1, wherein the excitation coil is a first excitation coil, and the pad further includes a second excitation coil, a third excitation coil, and a fourth excitation coil positioned circumferentially around a center, and the magnetic fields generated by the first excitation coil, the second excitation coil, the third excitation coil, and the fourth excitation coil comprise three orthogonal magnetic fields.

17. The system described in claim 16, wherein a first sensor coil includes a first sensor axis, a third sensor coil includes a third sensor axis, the first sensor axis being parallel to the third sensor axis, a second sensor coil includes a second sensor axis, and a fourth sensor coil includes a fourth sensor axis, the second sensor axis being parallel to the fourth sensor axis.

18. The system described in claim 17, wherein the first sensor axis is perpendicular to the second sensor axis, and the first excitation coil includes an excitation coil axis perpendicular to the first sensor axis and the second sensor axis.

Images