Robot-assisted thrombus probing

Abstract

A system (100) for probing a thrombus includes a robot controller (150) and an actuator. The robot controller (150) includes a memory (151) that stores instructions and a processor (152) that executes the instructions. The actuator is controlled by the robot controller (150) and is configured to drive at least one of a catheter (120) or a guidewire (121). When executed by the processor (152), the instructions cause the robot controller (150) to: determine a first amplitude and a first frequency for the actuator to drive the guidewire (121) to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire (121) at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.

Description

ROBOT-ASSISTED THROMBUS PROBINGBACKGROUND

[0001] A formal name for a blood clot is a thrombus. A thrombus is the product of blood coagulation in hemostasis. A thrombus has two components. The first component is aggregated platelets and red blood cells that form a plug. The second component is a mesh of cross-linked fibrin protein. Knowledge of the stiffness of the thrombus and the composition of the thrombus would be helpful information for an operator to know, as such knowledge may impact selection of a device to remove the thrombus. Therefore, any prior knowledge or knowledge that can be generated about the composition and the material of this clot composition would be helpful. Identification of the composition of the thrombus causing a stroke would likely provide critical insight into the most effective treatment approaches for avoiding repeated revascularization maneuvers and treatment failure, and various mechanisms for such identification have been proposed. Various mechanisms proposed for characterizing thrombus composition include spectral computed tomography (CT), optical spectroscopy to characterize color composition of the thrombus, and impedance-based sensors. These additional sensor or imaging techniques provide additional information about the clot composition but increase cost and complexity. The alternative of a direct measurement of the thrombus composition and its surrounding hardness has not been previously studied.

[0002] A direct measurement of thrombus composition would be valuable. For example, a detailed knowledge about the clot composition may enable fast and personalized treatment options and correct first time selections of tools and devices for treatment. However, adding sensor devices to obtain additional information about the clot composition generates more costs for a procedure due to additional devices and increased time requirements.SUMMARY

[0003] According to an aspect of the present disclosure, a system for probing a thrombus includes a robot controller and an actuator. The robot controller includes a memory that stores instructions and a processor that executes the instructions. The actuator is controlled by the robot controller and is configured to drive at least one of a catheter or a guidewire. When executed bythe processor, the instructions cause the robot controller to: determine a first amplitude and a first frequency for the actuator to drive the guidewire to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.

[0004] According to another aspect of the present disclosure, a controller for controlling a system for probing a thrombus includes a memory that stores instructions; and a processor that executes the instructions. When executed by the processor, the instructions cause the robot controller to: determine a first amplitude and a first frequency for an actuator to drive a guidewire to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.

[0005] According to another aspect of the present disclosure, a tangible, non-transitory computer-readable medium stores instructions. When executed by a processor, the instructions cause the processor to determine a first amplitude and a first frequency for an actuator to drive a guidewire to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The example embodiments are best understood from the following detailed description when read with the accompanying drawing figures. It is emphasized that the various features are not necessarily drawn to scale. In fact, the dimensions may be arbitrarily increased or decreased for clarity of discussion. Wherever applicable and practical, like reference numerals refer to like elements.

[0007] FIG. 1 illustrates a system for robot-assisted thrombus probing, in accordance with a representative embodiment.

[0008] FIG. 2 illustrates a method for robot-assisted thrombus probing, in accordance with arepresentative embodiment.

[0009] FIG. 3 illustrates a memory in robot-assisted thrombus probing, in accordance with a representative embodiment.

[0010] FIG. 4 illustrates a computer system, on which a method for robot-assisted thrombus probing is implemented, in accordance with another representative embodiment.DETAILED DESCRIPTION

[0011] In the following detailed description, for the purposes of explanation and not limitation, representative embodiments disclosing specific details are set forth in order to provide a thorough understanding of embodiments according to the present teachings. However, other embodiments consistent with the present disclosure that depart from specific details disclosed herein remain within the scope of the appended claims. Descriptions of known systems, devices, materials, methods of operation and methods of manufacture may be omitted so as to avoid obscuring the description of the representative embodiments. Nonetheless, systems, devices, materials and methods that are within the purview of one of ordinary skill in the art are within the scope of the present teachings and may be used in accordance with the representative embodiments. It is to be understood that the terminology used herein is for purposes of describing particular embodiments only and is not intended to be limiting. Definitions and explanations for terms herein are in addition to the technical and scientific meanings of the terms as commonly understood and accepted in the technical field of the present teachings.

[0012] It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements or components, these elements or components should not be limited by these terms. These terms are only used to distinguish one element or component from another element or component. Thus, a first element or component discussed below could be termed a second element or component without departing from the teachings of the inventive concept.

[0013] As used in the specification and appended claims, the singular forms of terms ‘a’, ‘an’ and ‘the’ are intended to include both singular and plural forms, unless the context clearly dictates otherwise. Additionally, the terms "comprises", and / or "comprising," and / or similar terms when used in this specification, specify the presence of stated features, elements, and / or components, but do not preclude the presence or addition of one or more other features, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any andall combinations of one or more of the associated listed items.

[0014] Unless otherwise noted, when an element or component is said to be “connected to”, “coupled to”, or “adjacent to” another element or component, it will be understood that the element or component can be directly connected or coupled to the other element or component, or intervening elements or components may be present. That is, these and similar terms encompass cases where one or more intermediate elements or components may be employed to connect two elements or components. However, when an element or component is said to be “directly connected” to another element or component, this encompasses only cases where the two elements or components are connected to each other without any intermediate or intervening elements or components.

[0015] The present disclosure, through one or more of its various aspects, embodiments and / or specific features or sub-components, is thus intended to bring out one or more of the advantages as specifically noted below.

[0016] As described herein, composition of a thrombus causing a stroke may be identified and used to provide critical insight into the most effective treatment approaches for avoiding repeated revascularization maneuvers and treatment failure. The identification may be performed during stroke thrombectomy interventions, and also during removal of thrombi in peripheral or other vasculatures, and / or for chronic total occlusions (CTOs). An easy measurement of the clot and its surrounding is provided by measuring the haptic frequency feedback of a "high" frequency mechanical stimulus given by a (robotic) catheter system, even when the feedback may be imperceptible to a human. Analysis of the frequency spectrum provides information about the mechanical characteristics of the thrombus. A response can be recorded as the excitation frequency / amplitude is controlled, and the response may take into account the mechanical transfer function of the catheter. The recorded response can be used as a measure for composition and used to guide the selection of treatment strategies.

[0017] FIG. 1 illustrates a system 100 for robot-assisted thrombus probing, in accordance with a representative embodiment.

[0018] The system 100 in FIG. 1 is a system for robot-assisted thrombus probing and includes components that may be provided together or that may be distributed. The system 100 includes an imaging device 101, a computer 110, a catheter 120, a guidewire 121, an intravascular filter 122, a robot 130, a motor 140, an encoder 145, a display 180, and a speaker 185.

[0019] The computer 110 includes a first interface 111, a second interface 112, a third interface 113, a fourth interface 114, and a robot controller 150. The robot controller 150 may comprise a robot controller as described herein and includes a memory 151 that stores instructions and a processor 152 that executes the instructions. The first interface 111 connects the computer 110 to the imaging device 101. The second interface 112 connects the computer 110 to the motor 140 and the encoder 145. The third interface 113 connects the computer 110 to the display 180. The fourth interface connects the computer 110 to the speaker 185. One or more of the interfaces may include ports, disk drives, wireless antennas, or other types of receiver circuitry that connect the robot controller 150 to other electronic elements. One or more of the interfaces may also include user interfaces such as buttons, keys, a mouse, a microphone, a speaker, a display separate from the display 180, or other elements that users can use to interact with the robot controller 150 of the computer 110 such as to enter instructions and receive output. A computer that can be used to implement the computer 110 is depicted in FIG. 4, though a computer 110 may include more elements than depicted in FIG. 1, and more or fewer elements than depicted in FIG. 4. In some embodiments, multiple different elements of the system 100 in FIG. 1 may include a controller such as the robot controller 150.

[0020] The imaging device 101 may comprise an X-ray system, an ultrasound system with a transducer, or another type of imaging device used during an interventional procedure. The imaging device 101 may also be representative of multiple types of imaging devices used for the teachings herein. For example, an X-ray system may be used to obtain an X-ray image before or at the start of an intervention, and an ultrasound system may be used during the intervention. Additionally, multiple types of imaging devices may be used during the intervention, such as an ultrasound system and optical shape sensing to sense the shape and location of the guidewire 121 relative to anatomy known from pre-interventional imaging.

[0021] The guidewire 121 is advanced in the arterial vasculature manually or by the robot 130 at the beginning of a thrombectomy procedure until the proximal part of the thrombus.

[0022] The intravascular filter 122 is an optional feature and may be configured to filter blood downstream of the thrombus and detect when material from the thrombus is caught in the intravascular filter 122 while the thrombus is being probed by the guidewire 121. The intravascular filter 122 may be difficult to place distally of the thrombus for smaller vessels. The intravascular filter 122 has multiple purposes, including to ensure that thrombus materialremoved from the thrombus during the probing does not end up in circulation in the vascular system in a manner that may cause another blockage distal of the thrombus being currently treated, as well as to detect the removal of thrombus material as part of the information used to characterize the thrombus.

[0023] The robot 130 may be controlled by the robot controller 150 as a robot controller and is configured to drive at least one of the catheter 120 or the guidewire 121. The robot 130 may steer the guidewire 121 via the catheter 120. The driving by the robot 130 may be controlled so that different frequency and amplitude combinations may be used to advance and retract the guidewire 121. Resistance from the thrombus encountered by the guidewire 121 may be analyzed in relationship to the frequency and amplitude combination being used to generate the resistance. Composition of the thrombus may be derived from the measurements and known information about the frequency and amplitude combinations being used.

[0024] The motor 140 may be configured to generate energy for the robot 130 as a translation of instructions from the robot controller 150 into mechanical motion used to drive at least one of the catheter 120 or the guidewire.

[0025] In some embodiments, an actuator may be implemented by one or more of the robot 130, the motor 140, the encoder 145, and the imaging device 101. For example, the actuator may be considered one or elements of each robot arm that directly interfaces with the catheter 120 or guidewire 121 by advancing, pulling back or rotating the catheter 120 or guidewire 121. For example, an ultrasound transducer may be used as a component of the imaging device 101, and electrical energy received by the transducer may be converted by the robot controller 150 as a robot controller into data used to activate the motor 140 to generate the energy for the robot 130. The robot 130 mechanically moves the catheter 120 and / or the guidewire 121 using mechanical motion. The actuator is controlled to advance the guidewire 121 to the thrombus and to retract the guidewire from the thrombus at the first frequency. In some embodiments, the robot 130 may be provided with a sensor that detects or otherwise senses the mechanical system response. For example, a sensor on the robot 130 may be provided to sense haptic feedback. Sensing directly at the robot drive may present a challenge if the distance is approximately 1 meter or greater as in a common clinical use case. In other embodiments, a sensor may be provided on the tip of the guidewire 121 and / or the tip of the catheter 120. For example, a force sensor may be provided on the tip of the guidewire 121 or the tip of the catheter 120.

[0026] The mechanical system response may comprise haptic feedback or another form of a mechanical system transfer function, including feedback that may not be perceptible to some, most or all humans.

[0027] The display 180 may be local to the robot controller 150 or may be remotely connected to the robot controller 150. The third interface 113 may be a local wired interface such as an Ethernet cable or a local wireless interface such as a Wi-Fi connection. The display 180 may be interfaced with other user input devices by which users can input instructions, including mouses, keyboards, thumbwheels and so on. The display 180 may be a monitor such as a computer monitor, a display on a mobile device, an augmented reality display, a television, an electronic whiteboard, or another screen configured to display electronic imagery. The display 180 may also include one or more input interface(s) such as those noted above with respect to the computer 110, and such interface(s) may connect to other elements or components, as well as an interactive touch screen configured to display prompts to users and collect touch input from users.

[0028] The speaker 185 may be configured to provide audio output and may also be local to the robot controller 150 or may be remotely connected to the robot controller 150. The fourth interface 114 may be a local wired interface such as an Ethernet cable or a local wireless interface such as a Wi-Fi connection.

[0029] The robot controller 150 may perform some of the operations described herein directly and may implement other operations described herein indirectly. For example, the robot controller 150 may indirectly control operations such as by generating and transmitting content to be displayed on the display 180. The robot controller 150 may directly control other operations such as logical operations performed by the processor 152 executing instructions from the memory 151 based on input received from electronic elements and / or users via the interfaces. Accordingly, the processes implemented by the robot controller 150 when the processor 152 executes instructions from the memory 151 may include steps not directly performed by the robot controller 150.

[0030] Using the system 100, the thrombus is carefully poked utilizing the guidewire 121 or a second catheter and the robot 130 is used to advance the wire into the thrombus and retract the wire subsequently. The advancing and retracting is automatically repeated with a specified combination of frequency and amplitude. The signal measured by a sensor on the tip of thecatheter 120, on the tip of the guidewire 121 or with the robot 130 as response of the actuator is indicative of the material crossed. The signal may indicate relative recovery of the tissue of the thrombus when probed at different frequencies and amplitudes, as this mechanical response function indicates health (e.g., robustness) of the thrombus. The frequency and / or amplitude of this probing and retraction may be modified to obtain a spectral response of the clot material. The amplitude is chosen to be small to avoid unintended damage to the vessel, but large enough to compensate for the elasticity of the catheter system, such as to generate a measurable response function signal at the sensor. The response function signal may be small enough to be imperceptible to a human given the small amplitude chosen to avoid unintended damage to the vessel.

[0031] Using the system 100, haptic frequency feedback of a “high” frequency mechanical stimulus may be measured. While the robot 130 is used in the system 100, some embodiments may use a catheter system that does not particularly require a robot. Analysis of the frequency spectrum and the haptic feedback provides information about the mechanical characteristics of the thrombus and its immediate surrounding. The recorded response can be used as a measure for composition of the thrombus to guide the selection of treatment strategies, such as locally applied thrombolysis, mechanical removal devices such as stent retrievers for thrombectomies, or even laser ablation techniques. The recorded response is provided by controlling the excitation frequency / amplitude and taking the mechanical transfer function of the catheter into account.

[0032] The system 100 is thus for probing a thrombus and includes the robot controller 150 as a robot controller comprising the memory 151 that stores instructions and the processor 152 that executes the instructions, along with an actuator controlled by the robot controller and configured to drive at least one of the catheter or the guidewire 121. As noted, the actuator may comprise one or more of the robot 130, the motor 140, the encoder 145, the imaging device 101, and in some embodiments a sensor on or with the robot 130 or on the tip of the guidewire 121 or the tip of the catheter 120 for sensing the haptic feedback. When executed by the processor, the instructions cause the robot controller 150 to determine a first amplitude and a first frequency for the actuator to drive the guidewire 121 to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire 121 at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire 121 at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the hapticfeedback. The computer 110 may therefor use the robot controller 150 to identify a treatment for the thrombus during the intravascular intervention; and output an identification for the treatment for the thrombus during the intravascular intervention.

[0033] FIG. 2 illustrates a method for robot-assisted thrombus probing, in accordance with a representative embodiment.

[0034] The method of FIG. 2 may be performed by the system 100 including the robot controller 150.

[0035] At S205, a thrombus location is identified.

[0036] At S210, a first point of contact is determined. The first point of contact may be a point of contact on the thrombus at the thrombus location. The first point of contact may be determined by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructions from the memory 151.

[0037] At S215, a first amplitude and first frequency is determined. The first amplitude and the first frequency may be determined by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructions from the memory 151. Frequencies of probing described herein are typically in the area of 1 hertz to 10 hertz, though the frequencies of probing may be higher than 10 hertz. The selected frequency may vary based on longitudinal stiffness of the catheter 120. The selected frequency may also vary based on the material of the catheter 120, as well as where the haptic frequency is being sensed relative to the catheter 120. For example, if a sensor used to measure the haptic feedback is on the tip of the catheter 120, the probing frequency may vary to be much higher than 10 hertz, such as 500 hertz or 1000 hertz or higher.

[0038] At S220, the method of FIG. 2 includes driving to a first point of contact. S220 may be performed by an actuator such as the robot 130 drive at least one of the catheter 120 or the guidewire 121 to the first point of contact. The driving at S220 may be performed at the first amplitude and the first frequency.

[0039] At S225, force or haptic feedback is measured. The haptic feedback measured at S225 is feedback that can be sensed by a human and / or physically measured by a sensor on / or with the catheter 120, or guidewire 121 or robot 130. For example, the haptic feedback measured at S225 may be a force that can be sensed by a sensor on / or with the robot 130 and imperceptible to some, most or any humans. The haptic feedback may include force due to the tissue response, thetissue stiffness, friction from the catheter 120, and / or other types of measurable force components that may vary based on the equipment being used, the combinations of frequency and amplitude being used, and the components of the thrombus. For example, if the haptic feedback is more dominated by friction of the catheter 120, the frequency response may reflect the force (amplitude) needed to obtain a specific amount of excitation, whereas if the haptic feedback is more dominated by amplitude, the frequency response may reflect more the stiffness of the thrombus.

[0040] The haptic feedback may be analyzed to determine recovery of the tissue in response to the probing. The measurements may be used to determine the mechanical response over the entirety of the catheter 120. The feedback is used to generate characteristics of the frequency response such indicative of elasticity of the thrombus.

[0041] At S230, a second point of contact is determined. The second point of contact may also be a point of contact on the thrombus at the thrombus location. The second point of contact may be determined by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructions from the memory 151.

[0042] At S235, a second amplitude and second frequency is determined. The second amplitude and the second frequency may be determined by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructions from the memory 151.

[0043] At S240, the method of FIG. 2 includes driving to a second point of contact. S240 may be performed by an actuator such as the robot 130 drive at least one of the catheter 120 or the guidewire 121. The driving at S240 may be performed at the second amplitude and the second frequency.

[0044] At S245, haptic feedback is measured. The haptic feedback measured at S245 is feedback that can be sensed by a human and / or physically measured by a sensor on / or with the catheter 120, the guidewire 121 or the robot 130. For example, the haptic feedback measured at S245 may be a force that can be sensed by a sensor on / or with the catheter 120, the guidewire 121 or the robot 130 and imperceptible to some, most or any humans. An example of a sensor which can be used to measure the haptic feedback is a piezo electric element.

[0045] The driving at S220 and S240 and subsequent retraction may be repeated several times at a certain spatial interval in the vessel and / or across the trans-axial cross-section of the thrombus. This provides the spectral probing response for the complete elongation and may be indicative ofdifferent compositions along the thrombus.

[0046] At S250, the spectral response is determined. The spectral response is determined based on the haptic feedback measured at S225 and S245. The spectral response is measured at S250 by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructions from the memory 151.

[0047] At S255, a composition of the thrombus is determined. The composition of the thrombus is determined at S255 by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructions from the memory 151. The classification of the thrombus mixture / composition at S255 may be based on a trained machine learning model. Compositions may be learned in ex-vivo models of thrombi gathered from previous interventions. Due to the numerous parameters involved and the minute “fingerprint” signal of the thrombus consistency, a large number of training data for the respective learning algorithm may be required to enable extraction of the frequency response specific to the thrombus. The parameters input for training may include, for example, stiffness / shape / friction of the catheter system components, variability of the surrounding vessel / tissue, constant motion of the system (particularly during cardiac interventions) and the minute “fingerprint” signal of the thrombus consistency.

[0048] Additional information about the thrombus characteristics may be gathered by utilizing protection systems such as the intravascular filter 122. The protection systems may be placed proximal and / or distal to the thrombus before the actuation via the catheter 120 starts. The protection system may be sensitive to haptic feedback. Fragments of the thrombus may be separated by the mechanical actuation of the thrombus. The amount and size of fragments can be estimated by the frequency and amplitude of potential fragments caught by the intravascular filter 122.

[0049] At S260, the composition of the thrombus is output. As an example, the composition may be provided as the percentages contained in the thrombus of red blood cells (RBC), platelets, fibrin and white blood cells (WBC).The estimated thrombus composition may be displayed to the interventionalist on the display 180 to support their decision on the thrombus removal device. The estimated thrombus composition may also be output by the speaker 185 based on data provided from the robot controller 150.

[0050] At S265, a treatment is identified. The treatment is identified at S265 by the robot controller 150 as a robot controller, and specifically by the processor 152 executing instructionsfrom the memory 151. The treatment may be a treatment for the thrombus to be performed during an intravascular intervention being performed while the method of FIG. 2 is performed. The treatment may be identified as one or more treatment option, or the identification may include selecting or at least suggesting one or more treatment devices such as stent retriever devices.

[0051] The method of FIG. 2 may also include the robot controller 150 identifying and providing additional information for the treatment for the thrombus at S265.

[0052] At S290, the identified treatment is output. The identified treatment may be output by the display 180 and / or by the speaker 185. The output identified treatment may comprise an identification for the treatment and may be output during the intravascular intervention performed while the method of FIG. 2 is performed. The treatment may be performed after S290, and during the same interventional procedure in which the method of FIG. 2 is performed.

[0053] In some embodiments based on the system 100 of FIG. 1 and the method of FIG. 2, the frequency and / or amplitude of the catheter 120 actuating the probing may be increased in such a way that the thrombus will be destroyed without any other devices needed. Thrombus fragments may be collected in the intravascular filter 122 or another component of a protection system to prevent further damage in distal vessels of the patient.

[0054] FIG. 3 illustrates a memory in robot-assisted thrombus probing, in accordance with a representative embodiment.

[0055] In FIG. 3, a memory 351 includes a first memory area 3511, a second memory area 3512, and a third memory area 3513. The memory 351 may comprise a flash memory, a random-access memory or another type of memory. The memory 351 may also include multiple different memories, such as different pages or banks of pages of random-access memory.

[0056] The first memory area 3511 stores data of a plurality of frequency and amplitude combinations, including a first frequency Fl and first amplitude Al, a second frequency F2 and second amplitude A2, a third frequency F3 and third amplitude A3, and a fourth frequency F4 and fourth amplitude A4.

[0057] The second memory area 3512 stores a trained machine learning model and / or another trained form of artificial intelligence. The third memory area 3513 stores instructions such as the instructions executed by the processor 152 in FIG. 1.

[0058] Using the ability to vary frequency and amplitude in order to generate a spectral response,the trained machine learning model may be used during an intervention to characterize a thrombus. In addition to probing the thrombus itself, the same principle described above may be used during insertion of the guidewire 121 and / or catheter 120. The overlay of microscopic motion (longitudinal vibration) may be indicative of the proper advancement of the devices along the vessel path, in that the transfer function may rapidly change if there are kinks in the path. In other embodiments, the actuator may be positioned close to the tip, in order to obtain a more direct feedback from the thrombus. In still other embodiments, these teachings may be combined with interventional imaging, (e.g. intravascular ultrasound (IVUS), spectral cone beam computed tomography (CBCT), spectral fluoroscopy, diffuse optical spectroscopy and / or optical coherence tomography (OCT).

[0059] FIG. 4 illustrates a computer system, on which a method for robot-assisted thrombus probing is implemented, in accordance with another representative embodiment.

[0060] Referring to FIG. 4, the computer system 400 includes a set of software instructions that can be executed to cause the computer system 400 to perform any of the methods or computer- based functions disclosed herein. The computer system 400 may operate as a standalone device or may be connected, for example, using a network 401, to other computer systems or peripheral devices. In embodiments, a computer system 400 performs logical processing based on digital signals received via an analog-to-digital converter.

[0061] In a networked deployment, the computer system 400 operates in the capacity of a server or as a client user computer in a server-client user network environment, or as a peer computer system in a peer-to-peer (or distributed) network environment. The computer system 400 can also be implemented as or incorporated into various devices, such as a workstation that includes a controller, a stationary computer, a mobile computer, a personal computer (PC), a laptop computer, a tablet computer, or any other machine capable of executing a set of software instructions (sequential or otherwise) that specify actions to be taken by that machine. The computer system 400 can be incorporated as or in a device that in turn is in an integrated system that includes additional devices. In an embodiment, the computer system 400 can be implemented using electronic devices that provide voice, video or data communication. Further, while the computer system 400 is illustrated in the singular, the term “system” shall also be taken to include any collection of systems or sub-systems that individually or jointly execute a set, or multiple sets, of software instructions to perform one or more computer functions.

[0062] As illustrated in FIG. 4, the computer system 400 includes a processor 410. The processor 410 may be considered a representative example of a processor of a controller and executes instructions to implement some or all aspects of methods and processes described herein. The processor 410 is tangible and non-transitory. As used herein, the term “non- transitory” is to be interpreted not as an eternal characteristic of a state, but as a characteristic of a state that will last for a period. The term “non-transitory” specifically disavows fleeting characteristics such as characteristics of a carrier wave or signal or other forms that exist only transitorily in any place at any time. The processor 410 is an article of manufacture and / or a machine component. The processor 410 is configured to execute software instructions to perform functions as described in the various embodiments herein. The processor 410 may be a general- purpose processor or may be part of an application specific integrated circuit (ASIC). The processor 410 may also be a microprocessor, a microcomputer, a processor chip, a controller, a microcontroller, a digital signal processor (DSP), a state machine, or a programmable logic device. The processor 410 may also be a logical circuit, including a programmable gate array (PGA), such as a field programmable gate array (FPGA), or another type of circuit that includes discrete gate and / or transistor logic. The processor 410 may be a central processing unit (CPU), a graphics processing unit (GPU), or both. Additionally, any processor described herein may include multiple processors, parallel processors, or both. Multiple processors may be included in, or coupled to, a single device or multiple devices.

[0063] The term “processor” as used herein encompasses an electronic component able to execute a program or machine executable instruction. References to a computing device comprising “a processor” should be interpreted to include more than one processor or processing core, as in a multi-core processor. A processor may also refer to a collection of processors within a single computer system or distributed among multiple computer systems. The term computing device should also be interpreted to include a collection or network of computing devices each including a processor or processors. Programs have software instructions performed by one or multiple processors that may be within the same computing device or which may be distributed across multiple computing devices.

[0064] The computer system 400 further includes a main memory 420 and a static memory 430, where memories in the computer system 400 communicate with each other and the processor 410 via a bus 408. Either or both of the main memory 420 and the static memory 430 may beconsidered representative examples of a memory of a controller, and store instructions used to implement some or all aspects of methods and processes described herein. Memories described herein are tangible storage mediums for storing data and executable software instructions and are non-transitory during the time software instructions are stored therein. As used herein, the term “non-transitory” is to be interpreted not as an eternal characteristic of a state, but as a characteristic of a state that will last for a period. The term “non-transitory” specifically disavows fleeting characteristics such as characteristics of a carrier wave or signal or other forms that exist only transitorily in any place at any time. The main memory 420 and the static memory 430 are articles of manufacture and / or machine components. The main memory 420 and the static memory 430 are computer-readable mediums from which data and executable software instructions can be read by a computer (e.g., the processor 410). Each of the main memory 420 and the static memory 430 may be implemented as one or more of random access memory (RAM), read only memory (ROM), flash memory, electrically programmable read only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, a hard disk, a removable disk, tape, compact disk read only memory (CD-ROM), digital versatile disk (DVD), floppy disk, blu-ray disk, or any other form of storage medium known in the art. The memories may be volatile or non-volatile, secure and / or encrypted, unsecure and / or unencrypted.

[0065] “Memory” is an example of a computer-readable storage medium. Computer memory is any memory which is directly accessible to a processor. Examples of computer memory include, but are not limited to RAM memory, registers, and register files. References to “computer memory” or “memory” should be interpreted as possibly being multiple memories. The memory may for instance be multiple memories within the same computer system. The memory may also be multiple memories distributed amongst multiple computer systems or computing devices.

[0066] As shown, the computer system 400 further includes a video display unit 450, such as a liquid crystal display (LCD), an organic light emitting diode (OLED), a flat panel display, a solid-state display, or a cathode ray tube (CRT), for example. Additionally, the computer system 400 includes an input device 460, such as a keyboard / virtual keyboard or touch-sensitive input screen or speech input with speech recognition, and a cursor control device 470, such as a mouse or touch-sensitive input screen or pad. The computer system 400 also optionally includes a disk drive unit 480, a signal generation device 490, such as a speaker or remote control, and / or a network interface device 440.

[0067] In an embodiment, as depicted in FIG. 4, the disk drive unit 480 includes a computer- readable medium 482 in which one or more sets of software instructions 484 (software) are embedded. The sets of software instructions 484 are read from the computer-readable medium 482 to be executed by the processor 410. Further, the software instructions 484, when executed by the processor 410, perform one or more steps of the methods and processes as described herein. In an embodiment, the software instructions 484 reside all or in part within the main memory 420, the static memory 430 and / or the processor 410 during execution by the computer system 400. Further, the computer-readable medium 482 may include software instructions 484 or receive and execute software instructions 484 responsive to a propagated signal, so that a device connected to a network 401 communicates voice, video or data over the network 401. The software instructions 484 may be transmitted or received over the network 401 via the network interface device 440.

[0068] In an embodiment, dedicated hardware implementations, such as application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), programmable logic arrays and other hardware components, are constructed to implement one or more of the methods described herein. One or more embodiments described herein may implement functions using two or more specific interconnected hardware modules or devices with related control and data signals that can be communicated between and through the modules. Accordingly, the present disclosure encompasses software, firmware, and hardware implementations. Nothing in the present application should be interpreted as being implemented or implementable solely with software and not hardware such as a tangible non-transitory processor and / or memory.

[0069] In accordance with various embodiments of the present disclosure, the methods described herein may be implemented using a hardware computer system that executes software programs. Further, in an exemplary, non-limited embodiment, implementations can include distributed processing, component / object distributed processing, and parallel processing. Virtual computer system processing may implement one or more of the methods or functionalities as described herein, and a processor described herein may be used to support a virtual processing environment.

[0070] Accordingly, robot-assisted thrombus probing enables measurement of composition of a thrombus for use in guiding selection of treatment strategies in order to avoid repeated revascularization maneuvers and treatment failure. The identification may be performed duringstroke thrombectomy interventions, and also during removal of thrombi in peripheral or other vasculatures, and / or for chronic total occlusions (CTOs). Measurement of the clot and its surrounding is readily provided by measuring the haptic frequency feedback of a "high" frequency mechanical stimulus given by a (robotic) catheter system, even when the feedback may be imperceptible to a human. Analysis of the frequency spectrum provides information about the mechanical characteristics of the thrombus. A response can be recorded as the excitation frequency / amplitude is controlled, and the response may take into account the mechanical transfer function of the catheter.

[0071] Although robot-assisted thrombus probing has been described with reference to several exemplary embodiments, it is understood that the words that have been used are words of description and illustration, rather than words of limitation. Changes may be made within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of robot-assisted thrombus probing in its aspects. Although robot-assisted thrombus probing has been described with reference to particular means, materials and embodiments, robot-assisted thrombus probing is not intended to be limited to the particulars disclosed; rather robot-assisted thrombus probing extends to all functionally equivalent structures, methods, and uses such as are within the scope of the appended claims.

[0072] The illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The illustrations are not intended to serve as a complete description of all of the elements and features of the disclosure described herein. Many other embodiments may be apparent to those of skill in the art upon reviewing the disclosure. Other embodiments may be utilized and derived from the disclosure, such that structural and logical substitutions and changes may be made without departing from the scope of the disclosure. Additionally, the illustrations are merely representational and may not be drawn to scale. Certain proportions within the illustrations may be exaggerated, while other proportions may be minimized. Accordingly, the disclosure and the figures are to be regarded as illustrative rather than restrictive.

[0073] One or more embodiments of the disclosure may be referred to herein, individually and / or collectively, by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any particular invention or inventive concept. Moreover, although specific embodiments have been illustrated and described herein, it shouldbe appreciated that any subsequent arrangement designed to achieve the same or similar purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all subsequent adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the description.

[0074] The Abstract of the Disclosure is provided to comply with 37 C.F.R. § 1.72(b) and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the foregoing Detailed Description, various features may be grouped together or described in a single embodiment for the purpose of streamlining the disclosure. This disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter may be directed to less than all of the features of any of the disclosed embodiments. Thus, the following claims are incorporated into the Detailed Description, with each claim standing on its own as defining separately claimed subject matter.

[0075] The preceding description of the disclosed embodiments is provided to enable any person skilled in the art to practice the concepts described in the present disclosure. As such, the above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments which fall within the true spirit and scope of the present disclosure. Thus, to the maximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the following claims and their equivalents and shall not be restricted or limited by the foregoing detailed description.

Claims

CLAIMS:We claim:

1. A system (100) for probing a thrombus, comprising: a robot controller (150) comprising a memory (151) that stores instructions and a processor (152) that executes the instructions; and an actuator controlled by the robot controller (150) and configured to drive at least one of a catheter (120) or a guidewire (121), wherein, when executed by the processor (152), the instructions cause the robot controller (150) to: determine a first amplitude and a first frequency for the actuator to drive the guidewire (121) to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire (121) at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.

2. The system (100) of claim 1, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: identify a treatment for the thrombus during the intravascular intervention; and output an identification for the treatment for the thrombus during the intravascular intervention.

3. The system (100) of claim 1, further comprising: the catheter (120); and the guidewire (121).

4. The system (100) of claim 1, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: determine a second amplitude and a second frequency for the actuator to drive the guidewire (121) to probe a thrombus during the intravascular intervention;control the actuator to drive the guidewire (121) at the second amplitude and the second frequency; and measure the haptic feedback from driving the guidewire (121) at the second amplitude and the second frequency, wherein the composition is determined based on measuring the haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency and from driving the guidewire (121) at the second amplitude and the second frequency.

5. The system (100) of claim 4, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: determine a spectral response of the thrombus from measuring the haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency and from driving the guidewire (121) at the second amplitude and the second frequency.

6. The system (100) of claim 4, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: determine a first point of contact on the thrombus for the guidewire (121); determine a second point of contact on the thrombus for the guidewire (121), and control the actuator to change from the first point of contact to the second point of contact.

7. The system (100) of claim 1, wherein the haptic feedback is measured based on a mechanical system (100) transfer function of the catheter (120).

8. The system (100) of claim 1, further comprising: an intravascular filter (122) configured to filter blood downstream of the thrombus and detect when material from the thrombus is caught in the intravascular filter (122) while the thrombus is being probed.

9. The system (100) of claim 1, wherein the actuator is controlled to advance the guidewire (121) to the thrombus and to retract the guidewire (121) from the thrombus at the first frequency.

10. The system (100) of claim 1, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: apply a trained machine learning model to measurements of the haptic feedback to determine the composition of the thrombus.

11. The system (100) of claim 1, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: apply a trained machine learning model to a system (100) transfer function to determine the composition of the thrombus.

12. The system (100) of claim 1, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: output a description of the composition of the thrombus determined based on measuring the haptic feedback.

13. The system (100) of claim 1, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: identify a location of the thrombus from an image; and control the actuator to drive the guidewire (121) to the location of the thrombus identified from the image.

14. A robot controller (150) for controlling a system (100) for probing a thrombus, comprising: a memory (151) that stores instructions; and a processor (152) that executes the instructions; wherein, when executed by the processor (152), the instructions cause the robot controller (150) to: determine a first amplitude and a first frequency for an actuator to drive a guidewire (121) to probe a thrombus during an intravascular intervention;control the actuator to drive the guidewire (121) at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.

15. The robot controller (150) of claim 14, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: provide additional information for treatment for the thrombus during the intravascular intervention; and output an identification for the treatment for the thrombus during the intravascular intervention.

16. The robot controller (150) of claim 14, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: determine a second amplitude and a second frequency for the actuator to drive the guidewire (121) to probe a thrombus during the intravascular intervention; control the actuator to drive the guidewire (121) at the second amplitude and the second frequency; and measure the haptic feedback from driving the guidewire (121) at the second amplitude and the second frequency, wherein the composition is determined based on measuring the haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency and from driving the guidewire (121) at the second amplitude and the second frequency.

17. The robot controller (150) of claim 16, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: determine a spectral response of the thrombus from measuring the haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency and from driving the guidewire (121) at the second amplitude and the second frequency.

118. The robot controller (150) of claim 14, wherein, when executed by the processor (152), the instructions further cause the robot controller (150) to: apply a trained machine learning model to measurements of the haptic feedback to determine the composition of the thrombus.

19. A tangible, non-transitory computer-readable medium (482) that stores instructions, which when executed by a processor (152), cause the processor (152) to: determine a first amplitude and a first frequency for an actuator to drive a guidewire (121) to probe a thrombus during an intravascular intervention; control the actuator to drive the guidewire (121) at the first amplitude and the first frequency; measure a haptic feedback from driving the guidewire (121) at the first amplitude and the first frequency; and determine a composition of the thrombus based on measuring the haptic feedback.

Images