Patent Description:
In lung resection of nodules, it is becoming common practice to use localization tools to aid the surgical team in effective resection of nodules that may not be palpable with current techniques. Several preoperative and intraoperative techniques are presently being used for nodule localization. One of these techniques utilizes small fiducials that are guided to a position adjacent a lung nodule using medical imaging, such as computed tomography. <CIT> describes that lesions, biopsy sites, and other target sites in solid tissue are localized by positioning an illumination source adjacent the lesion in the solid tissue. Usually, the illumination source is positioned using a localization wire (<NUM>, <NUM>) which is percutaneously introduced to the lesion. <CIT> describes markers, probes, and related systems and methods are provided for localizing locations within a patient's body, e.g., a lesion within a breast. The marker includes an energy converter e.g., one or more photodiodes, for transforming light energy striking the marker into electrical energy, a storage device coupled to the energy converter for storing the electrical energy, a threshold element that closes a switch when the electrical energy reaches a predetermined threshold to discharge the electrical energy and cause the antenna to transmit a radio frequency (RF) signal. <CIT> describes a system for generating a excitation field for excitation of a leadless marker assembly. One aspect of the system comprises a source generator assembly having a power supply, an energy storage device, a switching network and a source coil interconnected and configured to deliver a magnetic excitation signal waveform.

The herein claimed invention relates to a tissue marking beacon according to claim <NUM>. Optional features are defined in the dependent claims. In accordance with an aspect of the disclosure, a tissue marking beacon includes a storage capacitor including an onboard power coil. The onboard power coil wirelessly receives energy from a radio frequency (RF) field generator and stores an electrical charge in the storage capacitor. A light-emitting diode (LED) emits pulsatile near-infrared (NIR) light upon receiving a current from the storage capacitor. A circuit is arranged between the storage capacitor and the LED. The circuit controls a flow of the current from the storage capacitor to the LED. A RF antenna receives external RF pulses and signals emission of the pulsatile NIR light from the LED in response to the external RF pulses.

In some aspects, the tissue marking beacon is configured to be implanted in a tumor. The tissue marking beacon is configured to be implanted using a syringe. The tissue marking beacon may be disposed in a titanium sleeve.

In some aspects, the circuit further includes a step-up circuit configured to increase a voltage supplied to the LED.

In some aspects, a logic circuit may control an emission pattern of the pulsatile NIR light.

In some aspects, a NIR camera detects emission of the pulsatile NIR light to determine a location of the tissue marking beacon. An emission pattern of the pulsatile NIR light is configured to be synchronized with a data capture rate and/or detector exposure (shutter) of the NIR camera.

In some aspects, a second LED emits pulsatile NIR light upon receiving a current from a second storage capacitor.

In some aspects, the emission pattern of the pulsatile NIR light from the LED is different from a second emission pattern of the pulsatile NIR light emitted from the second LED. A comparison of the emission pattern and the second emission pattern identifies a location and a depth of the tissue marking beacon.

In some aspects, a RF field generator is configured to emit RF energy.

In some aspects, the RF field generator is connected with the NIR camera. The RF field generator is configured to emit pulsatile RF energy to synchronize the emission pattern of the pulsatile NIR light with the data capture rate and/or detector exposure (shutter) of the NIR camera.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate aspects and features of the disclosure and, together with the detailed description below, serve to further explain the disclosure, in which:.

"About" or 'approximately" or "substantially" as used herein may be inclusive of the stated value and means within an acceptable range of variation for the particular value as determined by one of ordinary skill in the art, considering tolerances (e.g., material, manufacturing, use, environmental, etc.) as well as the measurement in question and the error associated with measurement of the particular quantity (e.g., the limitations of the measurement system). For example, "about:" may mean within one or more standard variations, or within ± <NUM>%, <NUM>%, <NUM>%, <NUM>% of the stated value.

Descriptions of technical features or aspects of an exemplary embodiment of the disclosure should typically be considered as available and applicable to other similar features or aspects in another exemplary embodiment of the disclosure. Accordingly, technical features described herein according to one exemplary embodiment of the disclosure may be applicable to other exemplary embodiments of the disclosure, and thus duplicative descriptions may be omitted herein.

Exemplary embodiments of the disclosure will be described more fully below (e.g., with reference to the accompanying drawings). Like reference numerals may refer to like elements throughout the specification and drawings.

Tumor localization refers to methods of identifying the specific location of tumors in organs pre and perioperatively. In recent years, surgeons have been exploring a variety of approaches for localization, including the use of radioactive seeds, magnetic markers, and RFID. No technologies have emerged to enable the surgeon to localize a marker while actively preforming surgery as current approaches for localization involve the use of a hand-held wand to target and range the seed or implant.

Described herein is a seed (e.g., a fiducial or a beacon) with a light emitting diode (LED) powered by an inductively coupled RF antenna. As an example, an <NUM> LED (e.g., having a range of from about <NUM> to about <NUM>) deeply penetrates tissue and can be imaged with Medtronic's Visionsense NIR imaging system®. The devices and systems described herein may be employed for tumor localization as deep as <NUM> (e.g., for lung cancer treatment). The LED may be configured to produce a pulsatile signal that is within the visible spectrum, and thus the LED may be identifiable intra-operatively using known white-light methods.

<FIG> illustrates a tissue marking system <NUM> in accordance with this disclosure. The system <NUM> generally includes a control module <NUM> having a display <NUM> for visualizing a position of a tissue marking beacon <NUM> (e.g., with respect to a surgical target such as a tumor in a patient's lung <NUM>), a camera <NUM>, an RF field generator <NUM> configured to emit RF energy, and the tissue marking beacon <NUM> configured to be located by the system <NUM>. The tissue marking beacon <NUM> may be injected into a tumor site pre-operatively or perioperatively and then used to identify the location of the tumor.

The camera <NUM> is a near-infrared (NIR) camera that detects emission of pulsatile NIR light from the tissue marking beacon <NUM> to determine a location of the tissue marking beacon <NUM>. An emission pattern of the pulsatile NIR light is synchronized with a data capture rate of the NIR camera <NUM>. For example, a shutter speed/frequency of the NIR camera <NUM> may be synchronized with the emission pattern of the pulsatile NIR light such that the NIR light is emitted precisely when the camera shutter is in an open position, thus allowing a minimal amount of electrical current to be used by the tissue marking beacon <NUM>.

The RF field generator <NUM> may be coupled with the NIR camera <NUM> to facilitate the synchronization between the data capture rate and/or detector exposure (shutter) of the NIR camera <NUM> and the emission pattern of NIR light. The RF field generator <NUM> is configured to emit pulsatile RF energy to control when NIR light is emitted from the tissue marking beacon <NUM>. While tissue marking beacon <NUM> is illustrated in <FIG>, any of the tissue marking beacons described herein may be employed by the tissue marking system <NUM>.

<FIG> illustrates a tissue marking beacon <NUM> in accordance with aspects of this disclosure. The tissue marking beacon <NUM> includes a storage capacitor <NUM> including an onboard power coil <NUM>. The storage capacitor <NUM> is an energy storage capacitor capable of high current discharge as a ratio of total energy stored. The onboard power coil <NUM> wirelessly receives energy from a radio frequency (RF) field generator (see, e.g., RF filed generator <NUM> of <FIG>) and stores an electrical charge in the storage capacitor <NUM>. A light-emitting diode (LED) <NUM> emits pulsatile near-infrared (NIR) light upon receiving a current from the storage capacitor <NUM>. A circuit (see, e.g., circuit <NUM> of <FIG>) is arranged between the storage capacitor <NUM> and the LED <NUM> and serves to control a flow of current from the storage capacitor <NUM> to the LED <NUM>. The circuit may be configured to control a flow of current from the storage capacitor <NUM> to the LED <NUM> in a manner that alternates an emission of light from multiple LEDs. The circuit may be configured to discharge current to the LED <NUM> based on a signal passed through the power coil <NUM>. The signal may be a cessation of transmitted power. An RF antenna <NUM> receives external RF pulses and signals emission of the pulsatile NIR light from the LED <NUM> in response to the external RF pulses. The RF pulses may be emitted from the RF filed generator <NUM>. The RF field generator may be adjacent to a patient's body, or may be positioned on an instrument inside the patient's abdomen.

Each of the tissue marking beacons described herein may be dimensioned to be implanted in a tumor by a syringe (e.g., a syringe having about a <NUM> gauge needle). For example, the tissue marking beacon <NUM> is configured to be implanted in a tumor to mark a location of the tumor. The tissue marking beacons described herein can be implanted by Electromagnetic Navigation Bronchoscopy (ENB) or by an endoluminal robot.

<FIG> illustrates a tissue marking beacon <NUM> in accordance with another aspect of this disclosure. The tissue marking beacon <NUM> is substantially the same as the other tissue marking beacons described herein, unless otherwise indicated. The tissue marking beacon <NUM> includes a storage capacitor <NUM>, an onboard power coil <NUM>, an LED <NUM>, and an RF antenna <NUM>. The tissue marking beacon <NUM> further includes a sleeve <NUM>. The tissue marking beacon <NUM> may be disposed in the sleeve <NUM> for injection into a tumor. The sleeve <NUM> may include or may be formed of titanium. Titanium is a highly durable and cost-effective material for manufacturing. Using titanium or another similar relatively low-conductivity metal reduces eddy current losses induced from the RF field generator <NUM>. As an example, the sleeve <NUM> may have a wall thickness of about <NUM>, an outer diameter of <NUM>, and a length of from about <NUM> to about <NUM>.

<FIG> illustrate a tissue marking beacon <NUM> in accordance with another aspect of this disclosure having at least two LEDs. For example, tissue marking beacon <NUM> includes a first LED <NUM> and a second LED <NUM>. An RF antenna <NUM> may signal NIR light emission from the first LED <NUM> and a corresponding RF antenna may signal NIR light emission from the second LED <NUM>. The first LED <NUM> is positioned at a first end portion <NUM> of the tissue marking beacon <NUM> and the second LED <NUM> is positioned at a second end portion <NUM> of the tissue marking beacon <NUM> opposite the first end portion <NUM>. The first LED <NUM> emits pulsatile NIR light upon receiving a current from a first storage capacitor <NUM>. The second LED <NUM> emits pulsatile NIR light upon receiving a current from a second storage capacitor <NUM>. Alternatively, a single storage capacitor may power each of the LEDs <NUM> and <NUM>.

<FIG> is a line graph <NUM> of an exemplary current discharge to an LED (e.g., LEDs <NUM>, <NUM> or <NUM>). As an example, the LED <NUM> may emit each pulse of NIR light for about <NUM>. The current discharge illustrated in <FIG> may be similarly applicable to other LEDs described herein, unless otherwise indicated.

<FIG> is a diagram of an exemplary circuit <NUM> for controlling the current discharge to LEDs <NUM>, <NUM> or <NUM>. The circuit <NUM> may further include a step-up circuit <NUM> (see, e.g., <FIG>) configured to increase a voltage supplied to LEDs <NUM>, <NUM> or <NUM>. <FIG> is a line graph <NUM> of an exemplary current step-up pattern of the step-up circuit <NUM>.

In some aspects, a logic circuit may control an emission pattern of the pulsatile NIR light emitted by LEDs <NUM>, <NUM> or <NUM>. The logic circuit may be onboard any of the tissue marking beacons described herein.

<FIG> displays a graph <NUM> illustrating exemplary pulsatile emission patterns of NIR light. As an example, each pulse of NIR light may be emitted for about <NUM>. <FIG> illustrates an external signaling device <NUM> employing exemplary circuit <NUM> and a receiver <NUM> employing exemplary circuit <NUM>.

<FIG> is a conceptual illustration of a solar photocell system <NUM> in accordance with an aspect of this disclosure including an external signaling device <NUM> a receiver <NUM> operating as a tissue marking beacon. The external signaling device <NUM> of the solar photocell system <NUM> may be on board the camera (e.g., camera <NUM>), and thus the RF pulses from the RF field generator <NUM> need not be used. The camera may include a low-pass filter. The external signaling device <NUM> may emit light signals to the receiver <NUM> to trigger a desired emission of pulsatile NIR light from at least one of the LEDs <NUM> or <NUM> of the receiver <NUM>. Thus, the camera <NUM> need not be coupled with the RF field generator <NUM> to synchronize the NIR emission pattern of the tissue marking beacon with the data capture rate of the camera <NUM>. The camera <NUM> may directly regulate synchronization with the tissue marking beacon. The receiver <NUM> includes photovoltaic power cells <NUM> and <NUM> operated by a control/storage capacitor configured to control a flow of current to the LEDs <NUM>, <NUM>.

The external signaling device <NUM> may transmit optical power at a first wavelength to the receiver <NUM>. The receiver <NUM> may store electrical power (e.g., in photovoltaic power cells <NUM> and <NUM>) and emit light of a second wavelength (e.g., different from the first wavelength) back to the external signaling device <NUM>. Thus, a shutter of external signaling device <NUM> may be synchronized with the emitted light having the second wavelength. As an example, a signal may be transmitted in the optical power at the first wavelength to control the synchronization between the shutter of external signaling device <NUM> and the emitted light having the second wavelength. As an example, the external signaling device may emit light of the first wavelength in a range of from about <NUM> to about <NUM> and at least one of LEDs <NUM> or <NUM> may emit light of the second wavelength in a range of from about <NUM> to about <NUM>.

To enhance position location or detection variations a second LED/LD (Laser Diode) is added to the tissue marking beacon. For example, an LED/LD could be attached to both ends of the tissue marking beacon. The resulting two points of light can be triangulated to provide a location over distance. Two or more sources of light can also provide a relative orientation of the tissue marking beacon in free space. Each of the two LEDs may be pulsed with different identifiable emission patterns (e.g., different frequencies and/or with different emission timing). Alternatively, variations in color/wavelengths of light may be employed to differentiate opposite ends of the tissue marking beacon.

Pulsing variations of each LED can provide discrimination based upon a (known) pulse repetition rate. Increased light intensity from the LED/LD can be achieved by pulsing the current through the diode(s).

Pulsing of RF Energy to charge the RF beacon can be made synchronous to the detection camera such that the shutter and or exposure to charge the detector is synchronized with the RF pulse to the tissue marking beacon. This allows for increased discrimination of ambient light and increased signal detection accuracy.

<FIG> illustrate dispersion patterns of a tissue marking beacon <NUM> in accordance with an aspect of this disclosure. Tissue marking beacon <NUM> is substantially the same as tissue marking beacon <NUM> described herein, unless otherwise indicated. The first emission pattern of the pulsatile NIR light from the first LED is different from a second emission pattern of the pulsatile NIR light emitted from the second LED. A comparison of the first emission pattern and the second emission pattern identifies a location and a depth of the tissue marking beacon <NUM>.

NIR light emitted from each LED may have a distinct spherical dispersion pattern. The relative intensity of the center intensity of light to the edge intensity of light allows a calculation of the depth of the tissue marking beacon <NUM> to be performed. This calculation may be performed because eccentricity of surface illuminations enables prediction of incident angles (see, e.g., <FIG>) and triangulation to estimate a depth of the tissue marking beacon <NUM>. The size and shape of a single dispersion pattern can be employed to predict a distance from a surface of the patient's skin to the tissue marking beacon <NUM>.

<FIG> is a diagram of an exemplary circuit <NUM> for controlling pulsatile emission patterns of two LEDs. <FIG> is a line graph <NUM> of an exemplary current discharge pattern of two LEDs in accordance with the disclosure.

<FIG> is a block diagram of an exemplary computer <NUM> of the control module <NUM> of <FIG>. The computer of the control module <NUM> may include a processor <NUM> connected to a computer-readable storage medium or a memory <NUM> which may be a volatile type memory, e.g., RAM, or a non-volatile type memory, e.g., flash media, disk media, etc. The processor <NUM> may be another type of processor such as, without limitation, a digital signal processor, a microprocessor, an ASIC, a graphics processing unit (GPU), field-programmable gate array (FPGA), or a central processing unit (CPU).

The memory <NUM> can be random access memory, read-only memory, magnetic disk memory, solid state memory, optical disc memory, and/or another type of memory. The memory <NUM> can communicate with the processor <NUM> through communication buses <NUM> of a circuit board and/or through communication cables such as serial ATA cables or other types of cables. The memory <NUM> includes computer-readable instructions that are executable by the processor <NUM> to operate the control module. The control module <NUM> may include a network interface <NUM> to communicate with other computers or a server. A storage device <NUM> may be used for storing data. The control module <NUM> may include an AI or machine learning module <NUM> (see, <FIG>) including one or more FPGAs <NUM>. The FPGAs <NUM> may be used for executing various machine learning algorithms such as those described herein (e.g., a location algorithm <NUM> or a camera shutter/LED synchronization algorithm <NUM>).

The storage device <NUM> of the control module <NUM> store one or more machine learning algorithms and/or models, configured to determine a location, depth, and/or directional orientation of at least one tissue locating beacon, and to render an image on the display <NUM> of the tissue locating beacon with respect to a patient's anatomy. The machine learning algorithm may apply mathematical models to determine a location, depth, and/or directional orientation of at least one tissue locating beacon, and to render an image on the display <NUM> of the tissue locating beacon with respect to a patient's anatomy. The machine learning algorithm(s) may be trained on and learn from experimental data and/or data from previous procedures initially input into the one or more machine learning applications in order to enable the machine learning application(s) to determine a location, depth, and/or directional orientation of at least one tissue locating beacon, and to render an image on the display <NUM> of the tissue locating beacon with respect to a patient's anatomy.

Machine learning algorithms are advantageous for use in determining a location, depth, and/or directional orientation of at least one tissue locating beacon, and to render an image on the display <NUM> of the tissue locating beacon with respect to a patient's anatomy, at least in that complex sensor components and pre-defined categorization rules and/or algorithms are not required. Rather, machine learning algorithms utilize initially input data to determine statistical features and/or correlations by analyzing data therefrom. Thus, with the one or more machine learning algorithms having been trained as detailed above, such can be used to determine a location, depth, and/or directional orientation of at least one tissue locating beacon, and to render an image on the display <NUM> of the tissue locating beacon with respect to a patient's anatomy.

The various embodiments disclosed herein may also be configured to work with robotic surgical systems and what is commonly referred to as "Telesurgery. " Such systems employ various robotic elements to assist the surgeon and allow remote operation (or partial remote operation) of surgical instrumentation. Various robotic arms, gears, cams, pulleys, electric and mechanical motors, etc. may be employed for this purpose and may be designed with a robotic surgical system to assist the surgeon during the course of an operation or treatment. Such robotic systems may include remotely steerable systems, automatically flexible surgical systems, remotely flexible surgical systems, remotely articulating surgical systems, wireless surgical systems, modular or selectively configurable remotely operated surgical systems, etc..

The robotic surgical systems may be employed with one or more consoles that are next to the operating theater or located in a remote location. In this instance, one team of surgeons or nurses may prep the patient for surgery and configure the robotic surgical system with one or more of the instruments disclosed herein while another surgeon (or group of surgeons) remotely control the instruments via the robotic surgical system. As can be appreciated, a highly skilled surgeon may perform multiple operations in multiple locations without leaving his/her remote console which can be both economically advantageous and a benefit to the patient or a series of patients.

The robotic arms of the surgical system are typically coupled to a pair of master handles by a controller. The handles can be moved by the surgeon to produce a corresponding movement of the working ends of any type of surgical instrument (e.g., end effectors, graspers, knifes, scissors, etc.) which may complement the use of one or more of the embodiments described herein. The movement of the master handles may be scaled so that the working ends have a corresponding movement that is different, smaller or larger, than the movement performed by the operating hands of the surgeon. The scale factor or gearing ratio may be adjustable so that the operator can control the resolution of the working ends of the surgical instrument(s).

Claim 1:
A tissue marking beacon (<NUM>), comprising:
a storage capacitor (<NUM>, <NUM>) including an onboard power coil (<NUM>), the onboard power coil configured to wirelessly receive energy from a radio frequency (RF) field generator (<NUM>) and store an electrical charge in the storage capacitor;
wherein the tissue marking beacon comprises at least one first light-emitting diode (LED) (<NUM>) configured to emit pulsatile near-infrared (NIR) light upon receiving a current from the storage capacitor; and
a second storage capacitor (<NUM>); and
at least one second LED (<NUM>).