WO2018150374A1

WO2018150374A1 - Sensor coil assembly

Info

Publication number: WO2018150374A1
Application number: PCT/IB2018/050973
Authority: WO
Inventors: Gregory K. OLSON; Anthony D. HILL; Troy T. Tegg
Original assignee: St Jude Medical International Holding SARL
Current assignee: St Jude Medical International Holding SARL
Priority date: 2017-02-17
Filing date: 2018-02-16
Publication date: 2018-08-23
Anticipated expiration: 2019-08-17

Abstract

A sensor coil assembly for use with an elongate medical device comprising a planar coil formed by a first conductive wire segment with a concentric pattern, the first conductive wire segment including a first coil end and a second coil end, and a flexible substrate wherein the planar coil is attached to the flexible substrate wherein the flexible substrate is coupled with the elongate medical device and aligned with an elongated axis of the elongate medical device. A catheter, comprising an elongated shaft, where the elongated shaft includes a proximal portion and a distal portion, a sensor coil assembly disposed on the distal portion of the elongated shaft, wherein the sensor coil assembly comprises a first conductive wire segment in a concentric pattern and a substrate.

Description

SENSOR COIL ASSEMBLY

BACKGROUND

a. Field

[0001] The present disclosure relates generally to an elongate medical device. In particular, the instant disclosure relates to a planar sensor coil assembly. b. Background Art

[0002] Medical devices, catheters, and/or cardiovascular catheters, such as

electrophysiology catheters can be used in a variety of diagnostic, therapeutic, mapping, and/or ablative procedures to diagnose and/or correct conditions such as atrial arrhythmias, including, for example, ectopic atrial tachycardia, atrial fibrillation, and atrial flutter.

Arrhythmias can create a variety of conditions including irregular heart rates, loss of synchronous atrioventricular contractions and stasis of blood flow in a chamber of a heart, which can lead to a variety of symptomatic and asymptomatic ailments and even death.

[0003] A medical device can be threaded through a vasculature of a patient to a site where the diagnostic, therapeutic, mapping, and/or ablative procedure to diagnose and/or treat the condition is performed. To aid in the delivery of the medical device to the site, sensors (e.g., electrodes, electromagnetic coils) can be placed on the medical device, which can receive signals that are generated proximate to the patient from a device (e.g.,

electromagnetic field generator). Based on the received signals, an orientation, and/or position of the medical device can be computed.

BRIEF SUMMARY

[0004] Various embodiments herein provide an elongate medical device. The elongate medical device can include a sensor coil assembly. In at least one embodiment, a sensor coil can be formed by a planar coil formed by a first conductive wire segment with a concentric pattern, the first conductive wire segment including a first coil end and a second coil end. In some embodiments, the sensor coil assembly can include a flexible substrate, wherein the flexible substrate is coupled with the elongate medical device and aligned with an elongated axis of the elongate medical device. [0005] Various embodiments herein provide a catheter. In at least one embodiment, the catheter can include an elongated shaft. The elongated shaft can include a proximal portion and a distal portion. A sensor coil can be disposed on the distal portion of the elongated shaft. The sensor coil assembly disposed on the distal portion of the elongated shaft can comprise a first conductive wire segment in a concentric pattern and a substrate.

[0006] Various embodiments herein provide a sensor coil assembly. In at least one embodiment, the sensor coil can include a first sensor coil formed from a first conductive wire segment and a second sensor coil formed from a second conductive wire segment. In at least one embodiment, the first and second sensor coils include a concentric pattern. The first and second sensor coils can overlap and can be electrically connected.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a diagrammatic view of an exemplary system for performing one or more diagnostic or therapeutic procedures, wherein the system comprises a magnetic field-based medical positioning system, in accordance with embodiments of the present disclosure.

[0008] Fig. 2A is an isometric end, side, and top view of a sensor coil assembly that includes an oval sensor coil (e.g., a circular, ovate, or elliptical sensor coil) and an optional substrate, wherein a longitudinal axis of the sensor coil is aligned with a longitudinal axis of the substrate, in accordance with embodiments of the present disclosure.

[0009] Fig. 2B is an isometric end, side, and top view of a sensor coil assembly that includes a sensor coil and substrate in accordance with embodiments of the present disclosure.

[0010] Fig. 2C is an isometric end, side, and top view of a sensor coil assembly that includes a rectilinear sensor coil (e.g., a rectangular or square sensor coil) and a substrate, in accordance with embodiments of the present disclosure.

[0011] Fig. 3 A is an isometric end, side, and top view of the sensor coil assembly in Fig. 2A wrapped around a tube, in accordance with embodiments of the present disclosure.

[0012] Fig. 3B is an isometric end, side, and top view of the sensor coil from the sensor coil assembly in Fig. 2A attached to a tube without a substrate, in accordance with embodiments of the present disclosure. [0013] Fig. 3C is an isometric end, side, and top view of the sensor coil assembly in Fig. 2A being attached to a tube such that a longitudinal axis of the sensor coil will be disposed at an angle not parallel to a longitudinal axis of the tube, in accordance with embodiments of the present disclosure.

[0014] Fig. 3D is an isometric end, side, and top view of the sensor coil assembly of Fig. 3C attached to the tube where the longitudinal axis of the sensor coil is disposed at an angle not parallel with the longitudinal axis of the tube, in accordance with embodiments in the present disclosure.

[0015] Fig. 3E is an isometric end, side, and top view of a first sensor coil assembly attached to a tube, wherein the longitudinal axis of the first sensor coil assembly is parallel to a longitudinal axis of the tube, and a second sensor coil assembly being attached to the tube over the first sensor coil assembly and oriented such that a longitudinal axis of the second sensor coil assembly will be disposed at an angle not parallel to the longitudinal axis of the tube and not parallel to the longitudinal axis of the first sensor coil, in accordance with embodiments of the present disclosure.

[0016] Fig. 3F is an isometric end, side, and top view of a first sensor coil assembly and a second sensor coil assembly attached to a tube, wherein a longitudinal axis of the first sensor coil assembly and a longitudinal axis of the second sensor coil assembly are circumferentially spaced, in accordance with embodiments of the present disclosure.

[0017] Fig. 3G is an end view of the first sensor coil assembly and the second sensor coil assembly of Fig. 3F, in accordance with embodiments of the present disclosure.

[0018] Fig. 3H is an end view of an exemplary embodiment of four sensor coil assemblies circumferentially spaced, in accordance with embodiments of the present invention.

[0019] Fig. 4 is a partial cross-sectional side view of a catheter that includes a sensor coil assembly, in accordance with embodiments of the present disclosure.

[0020] Fig. 5 is an isometric side view of catheter that includes two sensor coil assemblies, in accordance with embodiments of the present disclosure.

[0021] Fig. 6 is a cross-sectional end, side, and top view of multiple sensor coil assemblies, in accordance with embodiments of the present disclosure. [0022] Fig. 7A is a side view of a sensor coil assembly including a conductive segment in a spiral pattern around a tube, in accordance with embodiments of the present disclosure.

[0023] Fig. 7B is a cross-sectional end view of the sensor coil assembly depicted in Fig. 7A, in accordance with embodiments of the present disclosure.

[0024] Fig. 8A is a side view of a sensor coil assembly including a ring electrode and a conductive wire segment, in accordance with embodiments of the present disclosure.

[0025] Fig. 8B is a cross-sectional end view of the sensor coil assembly depicted in Fig. 8A, in accordance with embodiments of the present disclosure.

[0026] FIG. 9 depicts an exemplary embodiment of an irregular or asymmetrical concentric pattern for the wire segment of the sensor coil in accordance with various embodiments of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

[0027] In some embodiments, and with reference to FIG. 1, the system 10 can include a medical device 12 and a medical positioning system 14. The medical device can include an elongate medical device such as, for example and without limitation, a catheter, sheath, introducer, endoscope, or other device configured for insertion into the body. For purposes of illustration and clarity, the description below will be limited to an embodiment wherein the medical device 12 comprises a catheter (a sample catheter is shown in FIG. 1). It will be appreciated, however, that the present disclosure is not meant to be limited to catheters.

[0028] With continued reference to FIG. 1, the catheter 12 can be configured to be inserted into a patient's body 16, and more particularly, into the patient's heart 18. The catheter 12 can include a handle 20 that has a proximal end 30, a shaft 22 having a proximal end portion 24 and a distal end portion 26, and one or more sensors 28 mounted in or on the shaft 22 of the catheter 12. As used herein, "sensor 28" or "sensors 28" can refer to one or more sensors 28_1; 28₂, . . . 28N, as appropriate and as generally depicted. In an exemplary embodiment, the sensors 28 are disposed at the distal end portion 26 of the shaft 22. The catheter 12 can further include other conventional components such as, for example and without limitation, a temperature sensor, force sensors, additional sensors or electrodes, ablation elements (e.g., ablation tip electrodes for delivering RF ablative energy, high intensity focused ultrasound ablation elements, etc.), and corresponding conductors or leads. [0029] The shaft 22 can be an elongate, tubular, flexible member configured for movement within the body 16. The shaft 22 supports, for example and without limitation, sensors and/or electrodes mounted thereon, such as, for example, the sensors 28, associated conductors, and possibly additional electronics used for signal processing and conditioning. The shaft 22 can also permit transport, delivery, and/or removal of fluids (including irrigation fluids, cryogenic ablation fluids, and bodily fluids), medicines, and/or surgical tools or instruments. The shaft 22 can be made from conventional materials such as, for example, polyurethane, and define one or more lumens configured to house and/or transport electrical conductors, fluids, or surgical tools. The shaft 22 can be introduced into a blood vessel or other structure within the body 16 through a conventional introducer. The shaft 22 can then be steered or guided through the body 16 to a desired location, such as the heart 18, using means well known in the art.

[0030] The sensors 28 mounted in or on the shaft 22 of the catheter 12 can be provided for a variety of diagnostic and therapeutic purposes including, for example and without limitation, electrophysiological studies, pacing, cardiac mapping, and ablation. In an exemplary embodiment, one or more of the sensors 28 are provided to perform a location or position sensing function. More particularly, and as will be described in greater detail below, one or more of the sensors 28 are configured to be a positioning sensor that provides information relating to the location (e.g., position and orientation) of the catheter 12, and the distal end portion 26 of the shaft 22 thereof, in particular, at certain points in time.

Accordingly, in such an embodiment, as the catheter 12 is moved along a surface of a structure of interest of the heart 18 and/or about the interior of the structure, the sensor(s) 28 can be used to collect location data points that correspond to the surface of, and/or other locations within, the structure of interest. These location data points can then be used for a number of purposes such as, for example and without limitation, the construction of surface models of the structure of interest.

[0031] For purposes of clarity and illustration, the description below will be with respect to an embodiment wherein a single sensor 28 of the catheter 12 comprises a positioning sensor. It will be appreciated, however, that in other exemplary embodiments, which remain within the spirit and scope of the present disclosure, the catheter 12 can comprise more than one positioning sensor as well as other sensors or electrodes configured to perform other diagnostic and/or therapeutic functions. As will be described in greater detail below, the sensor 28 can include a pair of leads extending from a sensing element thereof (e.g., a coil) that are configured to electrically couple the sensor 28 to other components of the system 10, such as, for example, the medical positioning system 14. In some embodiments, the sensing element can be an electromagnetic position sensor, such as a sensor coil, which can sense a magnetic field that is generated in proximity to the patient. Depending on a position and orientation (P&O) of the electromagnetic position sensor, different electrical signals can be generated by the coil and transferred to the medical positioning system, for a determination of a location reading that can be indicative of the P&O of the electromagnetic position sensor.

[0032] The location readings can each include at least one or both of a P&O relative to a reference coordinate system, which can be the coordinate system of medical positioning system 14. For some types of sensors, the P&O can be expressed with five degrees-of- freedom (five DOF) as a three-dimensional (3D) position (i. e., a coordinate in three axes X, Y and Z) and two-dimensional (2D) orientation (e.g., an azimuth and elevation) of sensor 28 in a magnetic field relative to a magnetic field generator(s) or transmitter(s) and/or a plurality of electrodes in an applied electrical field relative to an electrical field generator (e.g., a set of electrode patches). For other sensor types, the P&O can be expressed with six degrees-of- freedom (six DOF) as a 3D position (i.e. , X, Y, Z coordinates) and 3D orientation (i.e. , roll, pitch, and yaw). Additional information about roll detection as it relates to six DOF can be found in U.S. patent 9,427, 172, titled "Roll Detection and Six Degrees of Freedom Sensor Assembly," which is hereby incorporated by reference as if set forth fully herein.

[0033] Fig. 2A is an isometric end, side, and top view of a sensor coil assembly that includes an oval sensor coil (e.g., a circular, ovate, elliptical sensor coil, similar to a the shape of an automotive "racetrack" (e.g., generally elliptical, but with longer, straight sides, and curved ends that may or may not have a straight section)) and an optional substrate, wherein a longitudinal axis of the sensor coil is aligned with a longitudinal axis of the substrate, in accordance with embodiments of the present disclosure. In some embodiments, the sensor coil assembly 38₂ can include a sensor coil 42i. In some embodiments, the sensor coil 42i can be arranged in an elongated pattern that aligns with the axis defined by a line & & . The sensor coil 42_1; as depicted in Fig. 2A, can be a planar elongated coil and can extend further in a first direction (e.g., along an x-axis) than in a second direction (e.g., along a y-axis). For example, the sensor coil 421 can extend along the longitudinal axis defined by line aiai. In other embodiments, the planar elongated coil can extend further in a different direction (e.g., longer along a y-axis and shorter along an x-axis). [0034] The sensor coil 42i can be formed from a conductive wire segment, which can include a first coil end 46i and a second coil end 48i. The conductive wire segment 45χ can be concentrically wound around an elongated central origin that extends along a longitudinal axis aiai. The conductive wire segment 451 can be concentrically wound in an elongated pattern (e.g. an oval pattern, a rectangular pattern, or an elliptical pattern). The concentric patterns can be symmetrical (e.g., equal spacing between the circles, curves, arcs, or other shapes of the pattern) or asymmetrical (e.g., irregular or variable spacing between the circles, curves, arcs, or other shapes of the pattern). The sensor coil 42i can be shaped in a generally flat (e.g. planar) configuration to fit on a substrate 40i. For example, the sensor coil 42i can be coplanar with the substrate 401. As used herein, "sensor coil 42" or "sensor coils 42" can refer to one or more sensors 42_1; 42₂, . . . 42N, as appropriate and as generally depicted. The sensor coil can function as a magnetic pickup (e.g., an electric guitar pickup) or a magnetic transducer.

[0035] In some embodiments, the substrate 401 can be formed of a semi-rigid material that can be flat (e.g., planar) and/or can include a flat surface upon which the sensor coil 42i can be disposed. The substrate 40i can be formed as, for example, a planar rectangle, square, circle, ellipses, or other shape. As depicted in Fig. 2A, the substrate 40i is a planar rectangle that extends along a longitudinal axis defined by line ai_ai. The longitudinal axis defined by line ai.ai is depicted as extending parallel to the elongate edges of the planar rectangle. In some embodiments, the longitudinal axis of the sensor coil 421 can be parallel with and/or coaxial with the longitudinal axis of the substrate 40_1; as depicted in Fig. 2A.

[0036] In some embodiments the substrate 401 can be formed of a flexible material that can be flat initially and later formed into a hollow cylinder that has an elongated axis defined by line aiai, for example, as depicted in Fig. 3A. Alternatively, in some embodiments, the sensor coil 42i can be formed to fit around an elongated axis defined by line ff, as depicted in Fig. 3B, and may not include a substrate 40i. The substrate can also be a tube, in some embodiments, upon which sensor coil 42i is attached. For example, the sensor coil 42i can be formed to fit around the tube. The tube can be a feature inside the catheter 12 including a fluid lumen, or a guide wire lumen, or other interior tubular structures (e.g., insulative or tubing bundling other wires/components), or a tubular structure designed to mount a flat coil. The sensor coil 421 can be attached to the tube by any suitable method including, for example an adhesive or additive manufacturing, and deposition processes. The sensor coil 42i can be connected by one or more wires or printed trace conductors to an electrical device including parts of a medical positioning system 14. Any of the sensor coil 42_x embodiments of the present disclosure can be connected to an electrical device including parts of a medical positioning system. In some embodiments, the sensor coil 42i can be fit inside a tube. For example, a substrate with a sensor coil 42i could be rolled up and inserted into a tube and then released causing the substrate to conform to an inner surface of the tube.

[0037] Fig. 2B is similar to Fig. 2A, but depicts an oval sensor coil and an optional substrate wherein a longitudinal axis of the sensor coil is offset from a longitudinal axis of the substrate, in accordance with embodiments of the present disclosure. In some embodiments, a longitudinal axis of the sensor coil assembly 38₂, defined by the line b₂b₂, can be disposed at an offset angle with respect to horizontal longitudinal axis of the substrate 40₂ defined by the line a₂a₂. Fox example, the sensor coil 42₂ can be disposed at an angle Θ with the axis defined by a line a₂a₂ as shown in Fig. 2B. The angle Θ with respect to the longitudinal axis of the substrate, as depicted in Fig. 2B. The angle Θ between the axes defined by the lines a₂a₂ and b₂b₂ can range between zero and 180 degrees.

[0038] In some embodiments, the sensor coil assembly 38₂ can be a conductive trace. The conductive trace can be formed by, for example, thin film deposition. The conductive trace can also be formed using a conductive ink through an ink jet process or additive manufacturing process. Additive manufacturing processes include material jetting and binder jetting and others described in American Society for Testing Materials (ASTM) group 42 definitions. The conductive trace can be formed by other suitable methods including screen printing, flexographic printing, and other material deposition/removal processes (vapor deposition, ink jet, atomization jets, aerosol jets, melt deposition, etc.), etching or other similar processes. The conductive trace can be formed on catheter components (e.g., the shaft 22, etc.) and/or non-catheter components (e.g., a substrate 40_x,). The sensor coil assembly 38₂ can then be covered with additional coatings. For example, a non-conductive or dielectric coating can be applied on top of the conductive trace for protection.

[0039] In some embodiments, the sensor coil 42₂ can be formed from a conductive wire segment. The conductive wire segment can include a first coil end 46₂ and a second coil end 48₂. In some embodiments, the sensor coil 42₂ can be arranged in generally concentric coils. The sensor coil 42₂ can be arranged so that that one end starts at the exterior outer edge of the substrate 40₂ and ends generally in the center of the substrate 40₂, in some embodiments. The sensor coil 40₂ can have a gap or a spacing between the adjacent wire segments that is equal throughout the coil. As an example, the spacing can be approximately 0.001 inches. The sensor coil 42₂ can also be referred to as a conductive trace. The width of the trace can be approximately 0.001 inches. The sensor coil 42₂ can have any suitable number of traces. An example of the number of traces is 25. The dimensions of the substrate 40₂ can be selected to fit a particular tube size. An exemplary set of dimensions for the substrate 40₂ is 0.125" wide by 0.140" long which would fit onto a tube with an outside diameter of 0.0445".

[0040] In some embodiments (not shown), the sensor coil can be covered by, for example, one or more substrates or layers of another material. For example, the sensor coil 42₂ can be formed by shaping a conductive wire segment (e.g., 45₂) into a pattern as described herein. The conductive wire segment can then be coupled with a substrate. In other embodiments (not shown), the sensor coil 42₂ can be sandwiched between two substrates or coated with a material (e.g., laminated) and then coupled with another element (e.g., a tube).

[0041] As shown in Fig. 2B, sensor coil assembly 38₂ can include a substrate 40₂ and a sensor coil 42₂. In some embodiments, the substrate 40₂ can have an axis defined by the line a₂a₂. The sensor coil assembly 38₂ can be fabricated so the sensor coil 42₂ is aligned with an axis defined by the line b₂b₂. The sensor coil 42₂ can be positioned at an angle Θ between lines a₂a₂ and b₂b₂. Varying the angle Θ from zero (when lines a₂a₂ and b₂b₂ are parallel) changes the properties of sensor coil 42₂. The angle Θ can be any angle that results in the desired properties of sensor coil assembly 38₂.

[0042] Fig. 2C is an isometric end, side, and top view of a sensor coil assembly that includes a rectilinear sensor coil (e.g., a rectangular or square sensor coil) and a substrate, in accordance with embodiments of the present disclosure. In some embodiments, the sensor coil assembly 38₃ can include a sensor coil 42₃. Sensor coil 42₃ can be formed from a conductive wire segment. The conductive wire segment can include a first coil end 46₃ and a second coil end 48₃. In some embodiments, the sensor coil 42₃ can be arranged in a concentric pattern (e.g., a series of concentric loops). The sensor coil 42₃ can be shaped in a generally flat configuration to fit on a substrate 40₃. In some embodiments, the substrate 40₃ can be formed of a semi-rigid material and can be a flat substrate that can be later formed into a hollow cylinder that has an elongated axis defined by line dd. In some embodiments the substrate 40₃ can be formed of a flexible material that can be flat initially and later formed into a hollow cylinder that has an elongated axis defined by line dd. Alternatively, in some embodiments, the sensor coil 42₃ can be formed to fit around an elongated axis defined by line dd, but may not include a substrate 40₃. The size of the sensor coil 42₃ can be any suitable size for the application. As an example the width of the sensor coil 42₃ could be 2 mm and the length 9 mm. The sensor coil 42₃ can be attached to the substrate 40₃ using any suitable means including, for example, an adhesive. The sensor coil 42₃ can have a gap or a spacing between the adjacent wire segments that is equal throughout the coil. As an example, the spacing can be approximately 0.00039". The sensor coil 42₃ can also be referred to as a conductive trace. The width of the trace can be approximately 0.00039". The conductive trace can have a thickness of 0.001 mm. The sensor coil 42₃ can include 40 traces. The multiple layers of sensor coils can be interconnected by, for example, conductive paths (also referred to herein as "vias") or other conductive traces that are orthogonal to other conductors. The different types of vias include through vias, blind vias or buried vias. See Fig. 6 for more detail on the via types. The orientation of the layers of sensor coils and vias can be arranged to facilitate correct electrical flow direction of all layers. The sensor coil 42₃ can have concentric loops that are rectangular. The rectangular concentric loops can differ slightly from the concentric loops depicted in Figs. 2A and 2B in that the transition between the winding aligned with the longitudinal axis defined by the line dd to the portion of the loop that is perpendicular to the axis defined by the dd can be closer to a right angle with a less gradual curve.

[0043] Fig. 3A is an isometric end, side, and top view of the sensor coil assembly in Fig. 2A, wrapped around a tube, in accordance with embodiments of the present disclosure.

Sensor coil 424 can be formed from a conductive wire segment. The conductive wire segment can include a first coil end 464 and a second coil end 484. In some embodiments, the sensor coil assembly 384 can be positioned so a longitudinal axis of the sensor coil assembly 384 is aligned with an axis defined by the line ee. The sensor coil assembly 384 can be secured to a location of a catheter feature like a tube. For example, the sensor coil assembly 384 can be attached to the exterior of a fluid lumen or other similar feature. The tube 544 is aligned with an axis defined by the line ee. The sensor coil assembly 384 can be secured to the tube 544 by any suitable means, including, for example, adhesive.

[0044] Fig. 3B is an isometric end, side, and top view of the sensor coil from the sensor coil assembly in Fig. 2A attached to a tube without a substrate in accordance with embodiments of the present disclosure. Sensor coil 42¾ can be formed from a conductive wire segment. The conductive wire segment can include a first coil end 46_¾ and a second coil end 48_¾. In some embodiments, sensor coil 42_¾ can be used with a tube 54_¾ without a substrate. The sensor coil 42_¾ can be attached to a tube 54_¾ by any suitable means including, for example, an adhesive. In some embodiments, a longitudinal axis of the sensor coil 42_¾ can be positioned to align with an axis defined by the line ff as shown in Fig. 3B.

[0045] Fig. 3C is an isometric end, side, and top view of the sensor coil assembly in Fig. 2A being attached to a tube such that a longitudinal axis of the sensor coil will be disposed at an angle not parallel to a longitudinal axis of the tube, in accordance with embodiments of the present disclosure. Sensor coil 42₆ can be formed from a conductive wire segment. The conductive wire segment can include a first coil end 46 and a second coil end 48₆. In some embodiments, a longitudinal axis of sensor coil assembly 38₆ can be aligned so that the sensor coil assembly 38δ can be aligned with the axis formed by the line b6b6. The sensor coil 42 can be positioned at an angle Θ between the axes defined by lines a&a6 and b6b6. Varying the angle Θ from zero (when lines ae and b b are parallel) changes the properties of sensor coil

42₆. The angle Θ can be any angle that results in the desired properties of sensor coil assembly 38₆. Fig. 3C shows sensor coil 38₆ is in a position before attaching to the tube 54₆.

[0046] Fig. 3D is an isometric end, side, and top view of the sensor coil assembly of Fig. 3C attached to the tube where the longitudinal axis of the sensor coil is disposed at an angle not parallel with the longitudinal axis of the tube, in accordance with embodiments in the present disclosure. Sensor coil 42₇ can be formed from a conductive wire segment. The conductive wire segment can include a first coil end 46₇ and a second coil end 48₇. In some embodiments, a longitudinal axis of sensor coil assembly 38₇ can be aligned so that the sensor coil assembly 38₇ can be aligned with the axis formed by the line b₇b₇. The sensor coil 42₇ can be positioned at an angle Θ between the axes defined by lines a₇a₇ and b₇b₇. Varying the angle Θ from zero (when lines a₇a₇ and b₇b₇ are parallel) changes the properties of sensor coil

42₇. The angle Θ can be any angle that results in the desired properties of sensor coil assembly 38₇. Fig. 3D shows sensor coil 38₇ is in a position after attaching to the tube 54₇.

[0047] Fig. 3E is an isometric end, side, and top view of a first sensor coil assembly attached to a tube, wherein the longitudinal axis of the first sensor coil assembly is parallel to a longitudinal axis of the tube, and a second sensor coil assembly being attached to the tube over the first sensor coil assembly and oriented such that a longitudinal axis of the second sensor coil assembly will be disposed at an angle not parallel to the longitudinal axis of the tube and not parallel to the longitudinal axis of the first sensor coil, in accordance with embodiments of the present disclosure. A tube 54g can include two sensor coil assemblies 38gA and 38»Β in accordance with embodiments of the present disclosure. Sensor coil 42»A can be formed from a first conductive wire segment 45gA- The first conductive wire segment 45gA can include a first coil end 46»A and a second coil end 48gA- Sensor coil 42»Β can be formed from a second conductive wire segment 45_8B. The second conductive wire segment 458B can include a first coil end 46SB and a second coil end 48SB which are hidden from view in Fig. 3E. In some embodiments, the sensor coils 38»Α and 38gB can be overlapped. The sensor coils assemblies 38»Α and 38»Β can be oriented so that the sensor coil 42»A can be aligned with the axis formed by line gsgs and the sensor coil 42»B can be aligned with the axis formed by a line a_&a_&. The sensor coils 42»A and 42»B can be attached to a substrate 40gA and 40gB. The sensor coils assemblies 38»A and 38»Β attached to a tube 54g using any suitable method including, for example, an adhesive. The tube 54g can have an axis defined by the line a₈a₈. Fig. 3E shows sensor coil assembly 38»A attached to a tube 54g and sensor coil assembly 38»Β is in a position before attaching to the tube 54g, where sensor coil assembly 38gB overlaps sensor coil assembly 38»Α· In this embodiment, the sensor coil assembly 38»A can have a sensor vector 57gA, where the sensor vector 57»A can be represented by line from the center of the coil and perpendicular to the plane of the sensor coil assemblies 38SA-B- The sensor coil assembly 38SB can have a sensor vector 57SB. AS shown in FIG. 3E, the sensor vectors 57»A and 5T$B can be unaligned (e.g., the sensor coil assemblies 38SA-B do not share the same sensor vector). The sensor coils can provide 6DOF capability (e.g., using the sensor vectors for the sensor coils). Any angle greater than 0° and less than 180° between the sensor vectors of the sensor coils can allow for the determination of 6DOF of the sensor coil assembly. The multiple layers of sensor coils can be interconnected by vias. See Fig. 6 for more detail on the via types. The orientation of the layers of sensor coils and vias can be arranged to facilitate correct electrical flow direction of all layers.

[0048] Fig. 3F is an isometric end, side, and top view of a first sensor coil assembly, a second sensor coil assembly, and a third sensor coil assembly attached to a tube, wherein a longitudinal axis of the first, the second, and the third sensor coil assemblies are

circumferential spaced, in accordance with embodiments of the present disclosure. A tube 54io can include three sensor coil assemblies 38IOA-C in accordance with embodiments of the present disclosure. Sensor coil 42IOA can be formed from a first conductive wire segment 45 ΙΟΑ· The first conductive wire segment 45 IOA can include a first coil end 46IOA and a second coil end 48ioAwhich are hidden from view in Fig. 3F. Sensor coil 42IOB can be formed from a second conductive wire segment 45 ΙΟΒ· Sensor coil 42ioc can be formed from a third conductive wire segment (45 wc, hidden from view in Fig. 3F). The second and third conductive wire segments 45 IOB and 45 ioc can include first coil ends 46IOB, 46IOC and second coil ends 48IOB_, 8IOC (hidden from view in Fig. 3F). The tube 54io can have an axis defined by a line a^aio. The sensor coils 38I₀A-C can be oriented so that a longitudinal axis of each of the sensor coils 38IOA-C can be aligned with the line aioaio but the sensor coils 38IOA-C can be spaced around a circumference of the tube 54₁₀. The circumferential spacing can be, for example, 120° between the longitudinal axes of the sensor coils 38IOA and 38IOB_. The circumferential spacing can vary depending on, for example, the size of the sensor coils 38IOA and 38IOB and desired characteristics of the sensors. In some embodiments, the sensor coils 38IOA-C can be on different substrates (e.g., the sensor coil 38IOA can be on a first substrate, 38IOB can be on a second substrate and 38ioc can be on a third substrate, similar to Fig. 3E) or the sensor coils 38IOA-C can be on the same substrate.

[0049] Fig. 3G is an end view of the first sensor coil assembly and the second sensor coil assembly of Fig. 3F, in accordance with embodiments of the present disclosure. As discussed above in reference to Fig. 3F, the sensor coils 38IOA-C (sensor coil 38io_c is hidden from view in Fig. 3G) )can, for example, be oriented so that a longitudinal axis of each of the sensor coils 38IOA-C can be aligned with the line aioaio (the tube 54io can have an axis defined by a line aioaio, which is represented by a dot in Fig. 3G) and the sensor coils 38IOA-C can be spaced around a circumference of the tube 54_lo. The circumferential spacing can be, for example, 120° between the longitudinal axes of the sensor coils 38IOA-C- Sensor vectors (not shown) for each of the sensor coils can be separated by, for example, 120° (similar as described above with respect to Fig. 3F). In some embodiments, the sensor vectors can be offset longitudinally.

[0050] In some embodiments, there can be only two sensor coils (e.g., sensor coils 38IOA and 38IOB) and the circumferential spacing between the coils (e.g., measured by the sensor vectors and/or the longitudinal axes) can be (similar to Fig. 3G) 30°, 45°, 60°, 90°, 100°, 120°, or 135°. Any angle between the sensor vectors greater than 0° and less than 180° is suitable_. In other embodiments with three sensor coils, the angles between the sensor vectors for the sensor coils can be different (e.g., instead of equal circumferential spacing of 120° as shown in Fig. 3G). For example, the two angles between the sensor vectors for the sensor coils can be 45° and 60°, 60° and 90°, 45° and 90°, etc.

[0051] Fig. 3H is an end view of an exemplary embodiment of four sensor coil assemblies circumferentially spaced, in accordance with embodiments of the present invention. Similar to the discussion above for Fig. 3G, , some embodiments can include four sensor coils 38HA-D coupled with a tube 54n. The sensor coils 38HA-D can be oriented so that a longitudinal axis of each of the sensor coils 38HA-D can be aligned with the line anan (which is represented by a dot in Fig. 3H) and the sensor coils 38n_A-D can be spaced around a circumference of the tube 54n. The circumferential spacing can be, for example, 90° between the longitudinal axes of the sensor coils 38HA-D- Sensor vectors (not shown) for each of the sensor coils can be separated by, for example, 90° (similar as described above with respect to Fig. 3F). Any angle between the sensor vectors greater than 0° and less than 180° is suitable. In some embodiments, the angles between the four sensor coil assemblies can vary. For example, the angles could be 45°, 90°, and 45°; 45°, 45°, and 90°; 45°, 90°, and 90°; 45°, 60°, and 90°;

[0052] Fig. 4 is a partial cross-sectional side view of a catheter that includes a sensor coil assembly, in accordance with embodiments of the present disclosure. In some embodiments, the catheter can include a shaft 22 io, which can be elongated and can include a proximal portion 64io and a distal portion 62io. In some embodiments, sensor coil 42io can be disposed in the distal portion 62io of the shaft 22io. The shaft 22io can have an elongated axis that travels through a center of the shaft 22io. In some embodiments, the sensor coil 42io can be shaped to fit around an interior feature of the shaft 22io disposed about the elongated axis, such that the shaft 22io is coaxial with the center axis of the sensor coil 42io. In another embodiment, the center axis of the sensor coil 42 io is not coaxial with the axis of the shaft 22io. The interior of the shaft 22i₀that is the feature that sensor coil 42i₀ is attached to can include a lumen, a guide wire lumen, or other interior tubular structure (e.g., insulative or tubing bundling other wires/components), or a tubular structure designed to mount a flat coil.

[0053] Fig. 5 is an isometric side view of catheter that includes two sensor coil assemblies, in accordance with embodiments of the present disclosure. In some

embodiments, the catheter can include a shaft 22n, which can be elongated and can include a proximal portion 64n and a distal portion 62n. The shaft 22n can have an elongated axis that travels through a center of the shaft 22n. In some embodiments, the sensor coil 42HA and a sensor coil 42 HB can be shaped to fit around an interior feature of the catheter 22 n disposed about the elongated axis, such that the shaft 22 n is coaxial with the center axis of the sensor coil 42HA and a sensor coil 42HB. In another embodiment, the center axis of the sensor coil 42HA and a sensor coil 42HB is not coaxial with the axis of the shaft 22n. The center axes of sensor coil 42HA and a sensor coil 42HB can be the same or they can be different. [0054] Fig. 6 is a cross-sectional end, side, and top view of multiple sensor coil assemblies, in accordance with embodiments of the present disclosure. More than one sensor coil can be used at a time and the sensor coils can be connected to provide specific properties. The sensor coils can be stacked on top of each other. Any suitable number of the sensor coils can be included in the stack. Stacked sensor coils 80 permit can, for example, produce a larger current when in a given magnetic field. This embodiment can provide a larger signal to noise ratio . The stacked sensor coils 80 can include sensor coils that overlap each other so that a portion of the sensor coils line up with each other vertically (e.g. when viewing the stacked sensor coils 80 from above all the sensor coils are aligned). The sensor coils can overlap each other (e.g., they can partially overlap or fully overlap) . The overlapped sensor coils can be individual coils that overlap (fully or partially).

[0055] The stacked sensor coils can be connected using vias or other suitable electrical connections known in the art. The vias can be a through via 90, a blind via 92, or a buried via 94. Any number of vias can be used to connect the stacked sensor coils and any combination of via types can be used. Typical materials for the sensor coils or conductive traces are copper or copper alloys. However, any suitable conductive material can be used. The conductive trace can be, for example attached to the substrate (e.g. conductive trace 824 can be attached to substrate 865 (not shown in Fig. 6). In some embodiments, additional conductive traces can be used to connect (e.g., electrically) adjacent conductive traces in different layers of the stacked sensor coil. For example, conductive traces 824 can connect (e.g., electrically) through the blind via 90 with conductive traces 82₃.

[0056] In some embodiments, a highly magnetic permeable material 84 can be used as one of the substrate layers (e.g., . In another embodiment, the conductive trace can be surrounded by another material, for example, the highly magnetic permeable material (e.g., conductive trace 824 is surrounded by highly magnetic permeable material 844). The substrate layers in the stacked sensor coils can be the same material (e.g., substrates 86i_₆ can be one material) or they can be different materials in each layer (e.g., substrates 86₂ and 86₃ can be one material and substrates 864 and 865 can be a different material. Examples of the highly magnetic permeable material include Mu metal or Metglas®.

[0057] Fig. 7A is a side view of a sensor coil assembly including a conductive segment in a spiral pattern around a tube, in accordance with embodiments of the present disclosure. In some embodiments, a sensor coil assembly 38i₃ can include a sensor coil 42i₃. The sensor coil 42i₃ can be wrapped around a tube 54i₃ in a spiral pattern. The spiral can be any suitable configuration. The sensor coil 42i₃ can be round wire, flat wire, or some other suitable shape. The sensor coil 42₁₃ can also be a conductive trace formed using any suitable method including, for example, thin film deposition. The conductive trace can be formed in other embodiments using an ink jet printing process or an additive manufacturing process. One exemplary configuration is a wire width of 60 micrometers and a height of 15 micrometers. The wire can have a connection at one end to facilitate connecting the sensor coil 42₁₃ to a wire or other electrical device. The connection can be any suitable size or shape. An exemplary shape can be a square connection approximately 100 micrometers long. An exemplary spacing of the spirals in the wire can be approximately 1 cm. The substrate can be any suitable material. An exemplary material is polyimide (PI). The diameter of the tubing can be approximately 575 micrometers.

[0058] Fig. 7B is a cross-sectional end view of the sensor coil assembly depicted in Fig. 7A, in accordance with embodiments of the present disclosure. In some embodiments, the sensor coil 42i₃ can be wrapped around a substrate 54i₃ in a spiral pattern. The sensor coil 421₃ can be coated with a material to improve the performance of the sensor coil 42₁₃. For example, the PI dielectric coating can be applied on top of the sensor coil 42₁ and substrate 54₁₃. As an example, the coating can be approximately 10 micrometers thick. Conductivity of the wire can be maximized through ink and annealing temperatures. For example, the conductivity of the wire can be dependent on both the wire size and materials. There are many materials and curing methods and can be used to generate the wire used in the sensor coil 42₁₃. Materials can include carbon nanotubes, conductive metal (e.g., silver, gold, copper, etc.), particles/nanowires (down to ion implanted) in carrier materials (e.g., polymers). The annealing/curing temperature can be achieved using thermal, radiative, photonic, chemical, laser, microwave, plasma & electronic processes. Annealing/curing the wire can change the properties (e.g., increase the conductivity) of the wire to improve performance.

[0059] Fig. 8A depicts a side view of a sensor coil assembly including a ring electrode and a conductive wire segment, in accordance with embodiments of the present disclosure. In some embodiments, the sensor coil assembly can include a ring conductor 6O15 around a tube 54i5 electrically connected to a wire 102^. The ring conductor 6O15 can be any suitable material including, for example, platinum. The wire 102^ can be round or some other suitable shape. The wire 102^ can be any suitable conductive material including, for example, silver, gold or copper. The wire 102^ can be any suitable length. The wire 102^ can include, for example, a trace conductor as previously discussed. One exemplary configuration is a wire width of 60 micrometers and a height of 15 micrometers. The wire 102i₅ can have a connection IOO15 at one end opposite the ring connector 6O15 to facilitate connecting the ring connector 6O15 to a wire or other electrical device. The connection IOO15 can be any suitable size or shape. An exemplary shape can be a square connection (e.g., a bonding pad) approximately 100 micrometers long. The connection IOO15 can be any suitable distance from the ring connector 6O15. An exemplary distance between the ring conductor 6O15 and the connection IOO15 is 10 cm. The tube 54i_¾ can be any suitable material. An exemplary material is Pebax^® polyether block amide (PEBA). The diameter of the tubing can be approximately 575 micrometers.

[0060] Fig. 8B is a cross-sectional end view of the sensor coil assembly depicted in Fig. 8A, in accordance with embodiments of the present disclosure. In some embodiments, the sensor coil can surround a substrate 54i_¾ in a ring conductor 6O15. The substrate 54i_¾ can be coated with a material to improve the performance of the sensor coil. For example, the PI dielectric coating can be applied on top of the ring conductor 6O15 and substrate 54ι¾. As an example, the coating can be approximately 10 micrometers thick.

[0061] The sensor coil can be designed to meet the performance levels of a current sensor set used. A current sensor set used is a wound sensor coil where cross-sectional area (A) is a main component of voltage output for the sensor coil:

[0062] V = μ * η * Α * (^)

[0063] where V is voltage, μίβ relative magnetic permeability, n is total number of coil turns, A is the cross-sectional area, H is magnetic field strength and t is time. A calculation for the flat layer area can be performed to determine the appropriate size to fit a catheter. Assuming that the sensor coil shape is an ellipse that decreases in radius, the formula for the area enclosed in one layer is:

[0064] A = (r_y - r_x) * * (1 - cos² (2 * π * N_turns)) + n * r * r_y * N_turns - ) * (r_x + Ty) * n * d * N_turns ² + * d² * π * N_turns ³

[0065] Where r_x and r_y are the outer radii in the X and Y directions, d is the total space between turns (it is the sum of the trace width and gap), N_turns does not have to be an integer. The elliptical spiral starts at (r_x, 0) and turns counter-clockwise. It is important that each layer turns the same direction or the voltages will cancel. [0066] Assume that:

[0067] r_x = 4.5e— 3 m, r_y = le— 3 m, d =0.002" (or 2 mil) where the trace is 1 mil and the gaps is 1 mil = 5.08e-5 m, N_turns = 10. This yields an area of 1.00 e-4 m² per layer. In this example, four sensor coils (or four layers) produces the desired sensor characteristics. The number of layers and the parameters (trace width, gap, number of turns, radius of the turns) can be adjusted to adjust the sensor characteristics.

[0068] The path followed by a wire segment forming a sensor coil according to embodiments of the present disclosure need not form or trace a symmetrically-looping pattern, such as the substantially symmetrical concentric patterns shown in, for example, FIGS. 2A-C. For example, any concentric pattern of circles, curves, arcs, or other shapes, including irregular or asymmetrical concentric patterns, may be used. For example, the distance between adjacent segments of the overall trace may vary as long as the concentric pattern is formed by without fully reversing directions. For example, any symmetrical or asymmetrical clockwise (or counterclockwise) concentric patterns are acceptable if the wire segment forming the concentric pattern does not fully reverse on itself. FIG. 9 depicts an exemplary embodiment of an irregular or asymmetrical concentric pattern for the wire segment of the sensor coil in accordance with various embodiments of the present disclosure. In the sensor coil depicted in FIG. 9, the wire segment 45 n forming the asymmetrical concentric pattern 104 traces a pattern with uneven spacing between adjacent sections or loops of wire, and the wire segment comprises a plurality of different curvatures.

[0069] Embodiments are described herein of various apparatuses, systems, and/or methods. Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and depicted in the accompanying drawings. It will be understood by those skilled in the art, however, that the embodiments can be practiced without such specific details. In other instances, well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. Those of ordinary skill in the art will understand that the embodiments described and illustrated herein are non-limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein can be representative and do not necessarily limit the scope of the embodiments, the scope of which is defined solely by the appended claims. [0070] Reference throughout the specification to "various embodiments," "some embodiments," "one embodiment," or "an embodiment", or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment(s) is included in at least one embodiment. Thus, appearances of the phrases "in various embodiments," "in some embodiments," "in one embodiment," or "in an embodiment," or the like, in places throughout the specification, are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment can be combined, in whole or in part, with the features, structures, or characteristics of one or more other embodiments without limitation given that such combination is not illogical or non-functional.

[0071] It will be appreciated that the terms "proximal" and "distal" can be used throughout the specification with reference to a clinician manipulating one end of an instrument used to treat a patient. The term "proximal" refers to the portion of the instrument closest to the clinician and the term "distal" refers to the portion located furthest from the clinician. It will be further appreciated that for conciseness and clarity, spatial terms such as "vertical," "horizontal," "up," and "down" can be used herein with respect to the illustrated embodiments. However, surgical instruments can be used in many orientations and positions, and these terms are not intended to be limiting and absolute.

[0072] Although at least one embodiment of a sensor coil assembly has been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this disclosure. All directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present disclosure, and do not create limitations, particularly as to the position, orientation, or use of the devices. Joinder references (e.g., affixed, attached, coupled, connected, and the like) are to be construed broadly and can include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily infer that two elements are directly connected and in fixed relationship to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure can be made without departing from the spirit of the disclosure as defined in the appended claims.

[0073] Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials do not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

Claims

What is claimed is:

1. A sensor coil assembly for use with an elongate medical device, comprising:

a planar coil formed by a first conductive wire segment with a concentric pattern, the first conductive wire segment including a first coil end and a second coil end; and

a flexible substrate wherein the planar coil is coupled to the flexible substrate, and wherein the flexible substrate is coupled with the elongate medical device and aligned with an axis of the elongate medical device.

2. The sensor coil assembly of claim 1, wherein the first conductive wire segment is formed from at least one of a unitary piece of wire and a continuous conductive trace.

3. The sensor coil assembly of claim 2, wherein the a portion of the concentric pattern extends along a longitudinal axis extending parallel to the elongate edges of the substrate.

4. The sensor coil assembly of claim 3, wherein the concentric pattern comprises a symmetrical pattern or an asymmetrical pattern.

5. The sensor coil assembly of claim 1, wherein the sensor coil is coupled with a tube.

6. The sensor coil assembly of claim 1, further comprising a non-conductive coating covering the sensor coil.

7. The sensor coil assembly of claim 2, wherein the first conductive wire segment is formed from at least one of a plurality of pieces of wire and a plurality of conductive traces.

8. The sensor coil assembly of claim 7, wherein the flexible substrate or the planar coil is coupled with the elongate medical device.

9. A catheter, comprising:

an elongated shaft, wherein the elongated shaft includes a proximal portion and a distal portion,

a sensor coil assembly disposed on the distal portion of the elongated shaft, wherein the sensor coil assembly comprises a first conductive wire segment in a concentric pattern and a substrate.

10. The catheter of claim 9, wherein the concentric pattern is selected from the group consisting of a symmetrical concentric pattern and an asymmetrical concentric pattern.

11. The catheter of claim 9, wherein a longitudinal axis of the sensor coil assembly is aligned with an axis of the catheter.

12. The catheter of claim 9, wherein a longitudinal axis of the sensor coil assembly is disposed at an angle with respect to an axis of the catheter.

13. The catheter of claim 11, further comprising a second sensor coil assembly disposed on the distal portion of the elongated shaft, wherein the second sensor coil assembly comprises a second conductive wire segment.

14. The catheter of claim 13, where a second longitudinal axis of second sensor coil assembly is aligned with the longitudinal axis of the elongated shaft and the sensor coil assembly and the second sensor coil assembly are circumferentially spaced around the catheter.

15. A sensor coil assembly, comprising:

a first sensor coil formed from a first conductive wire segment; and

a second sensor coil formed from a second conductive wire segment;

wherein the first and second sensor coils include a concentric pattern, and wherein the first and second sensor coils overlap and are electrically connected.

16. The sensor coil assembly of claim 15, wherein the first and second sensor coils are electrically connected with a plurality of vias.

17. The sensor coil assembly of claim 16, wherein the first and second sensor coils overlap and the first and second conductive wire segments are parallel at a plurality of portions.

18. The sensor coil assembly of claim 15, wherein the first sensor coil and second sensor coil are formed from a plurality of conductive wire segments.

19. The sensor coil assembly of claim 15, further comprising a non-conductive coating covering the first and second sensor coils.

20. The sensor coil assembly of claim 15, further comprising a magnetic permeable material in at least one of the first sensor coil and the second sensor coil.