Medical device having acoustic sensor and method for locating medical device and acoustic source

Abstract

The catheter comprises a shaft; a tip disposed at a distal end of the shaft; at least one acoustic sensor disposed on or in the shaft, each acoustic sensor disposed at a respective distance from a distal end of the shaft; and at least one electrical conductor disposed on or in the shaft, each electrical conductor electrically connecting a respective acoustic sensor to one or more electrical connection points in the housing, the housing being attached to the proximal end of the shaft. The conduit and the sound source are positioned relative to each other using acoustic signals transmitted between the sound source and the conduit.

Description

Cross-references to related applications

[0001] This application claims priority to U.S. Provisional Application No. 63 / 498,297, filed April 26, 2023, entitled “System and method for use with respect to catheter positioning therapy device,” which is incorporated herein by reference. Technical Field

[0002] This application relates in general to a medical device having one or more acoustic sensors, and to positioning a sound source relative to such a medical device. Background Technology

[0003] Many treatment procedures require locating and monitoring the position of catheters within blood vessels. While X-ray imaging can visualize catheters, alternative methods that do not use ionizing radiation are preferred. Ultrasound scanners can provide non-ionizing visualization, but image resolution can be challenging, making reliable identification and monitoring of catheter position difficult. For example, image resolution is better at higher frequencies with poor penetration depth, making ultrasound imaging difficult at greater depths. There is a desire to improve the ability to locate and monitor catheter position without using ionizing radiation.

[0004] For many treatment procedures, the location of the catheter is desirable as a marker, for example, to deliver electromagnetic or acoustic energy to specific areas of the body. Delivering acoustic energy to a target is often associated with a variety of challenges. One challenge is the alignment of the ultrasound beam on the target, which is also affected by the diffraction and deflection of sound waves as they travel along the acoustic path through different layers of tissue to reach the target. Another challenge is the acoustic coupling between the sound source and the patient's skin, and creating an acoustic window within the patient's body for an effective channel of sound waves to the target. Summary of the Invention

[0005] The exemplary embodiments described herein are innovative in that no single feature is indispensable or solely responsible for its desired properties. The following description and accompanying drawings illustrate certain illustrative implementations of this disclosure, indicating several exemplary ways in which various principles of this disclosure can be implemented. However, the illustrative examples are not exhaustive of the many possible embodiments of this disclosure. Some advantageous features will now be summarized without limiting the scope of the claims. Other objects, advantages, and novel features of this disclosure will be set forth in the following detailed description of the disclosure when considered in conjunction with the accompanying drawings, which are intended to illustrate and not limit the invention.

[0006] One aspect of the invention relates to a conduit comprising: a shaft; a tip disposed at a distal end of the shaft; at least one acoustic sensor disposed on or in the shaft, each acoustic sensor being disposed at a corresponding distance from the distal end of the shaft; and at least one electrical conductor disposed on or in the shaft, each electrical conductor electrically connecting a corresponding acoustic sensor to one or more electrical connection points in a housing attached to a proximal end of the shaft.

[0007] In one or more embodiments, each acoustic sensor includes a piezoelectric polymer diaphragm disposed around at least a portion of the outer periphery of the shaft. In one or more embodiments, the piezoelectric polymer diaphragm includes polyvinylidene fluoride (PVDF).

[0008] In one or more embodiments, the shaft includes an inner tube and an outer tube, a corresponding piezoelectric polymer film is disposed around at least a portion of the outer periphery of the inner tube, and at least one electrical conductor is disposed between the inner and outer tubes. In one or more embodiments, the inner tube is defined by a wall having an inner wall thickness, and one or more regions of the wall have an increased thickness compared to the inner wall thickness. In one or more embodiments, the outer tube is defined by a wall having an outer wall thickness, and one or more regions of the wall have an increased thickness compared to the outer wall thickness. In one or more embodiments, a spacer is provided between the inner and outer tubes.

[0009] In one or more embodiments, one or more electrical connection points are electrically connected to cables extending through the housing. In one or more embodiments, one or more electrical connection points are formed on a printed circuit board disposed within the housing. In one or more embodiments, the conduit further includes wireless communication circuitry electrically connected to one or more electrical connection points.

[0010] In one or more embodiments, the housing includes a port having a hole aligned with a central channel of the shaft. In one or more embodiments, at least one acoustic sensor includes a first acoustic sensor and a second acoustic sensor, the first acoustic sensor and the second acoustic sensor being separated by a predetermined distance.

[0011] Another aspect of the invention relates to a method for locating a sound source and a medical device relative to each other, the method comprising: a. introducing the medical device into a mammal; b. acoustically coupling a sound source to the mammal at a location corresponding to a target location of the medical device, the sound source including a housing and a source transducer disposed within the housing; c. generating an acoustic signal using the source transducer; d. receiving the acoustic signal using an acoustic sensor on or within the medical device, the acoustic sensor being in electrical or wireless communication with a detector; e. determining the time of flight (ToF) of the acoustic signal transmitted between the source transducer and the acoustic sensor using the detector; f. determining the distance between the source transducer and the acoustic sensor using the detector and the ToF; and g. locating the sound source and the medical device relative to each other in real time using the detector, at least in part based on the distance between the source transducer and the acoustic sensor.

[0012] In one or more embodiments, the acoustic sensor is a first acoustic sensor, the medical device includes at least a second acoustic sensor, and the method further includes receiving acoustic signals using the first and second acoustic sensors; determining a first Time of Flight (ToF) of the acoustic signals transmitted between a source transducer and the first acoustic sensor using a detector; determining a second ToF of the acoustic signals transmitted between the source transducer and the second acoustic sensor using a detector; determining a first distance between the source transducer and the first acoustic sensor using the detector and the first ToF; determining a second distance between the source transducer and the second acoustic sensor using the detector and the second ToF; and locating the sound source and the medical device relative to each other, at least in part, based on the first and second distances.

[0013] In one or more embodiments, the medical device includes a plurality of acoustic sensors, the sound source includes a plurality of source transducers, and the method further includes sequentially generating acoustic signals using at least a first source transducer and a second source transducer of the plurality of source transducers; receiving the acoustic signals using each acoustic sensor; determining a corresponding Time of Flight (ToF) in the acoustic signals transmitted between (a) each of the at least first source transducers and the second source transducers and (b) each acoustic sensor; using each ToF to determine a corresponding distance between (a) each of the at least first source transducers and the second source transducers and (b) each acoustic sensor; and positioning the sound source and the medical device relative to each other, at least in part, based on the corresponding distances.

[0014] In one or more embodiments, the location is a first location, and the method further includes moving the sound source to a second location after performing at least steps b-f when the sound source is in the first location, and repeating steps b-f when the sound source is in the second location, so as to improve the resolution of the positioning of the sound source and the medical device relative to each other compared to performing positioning only when the sound source is in the first location.

[0015] In one or more embodiments, the medical device includes a catheter that is introduced into an organ, and the method further includes introducing an acoustic enhancer into a region adjacent to the calcification via the catheter; applying acoustic energy using an acoustic source; and generating cavitation with the acoustic energy and the acoustic enhancer to decompose at least a portion of the calcification.

[0016] In one or more embodiments, the method further includes using a robotic locator in communication with the detector to adjust the position of the sound source based on the positioning of the sound source and the medical device relative to each other. In one or more embodiments, the method further includes displaying the relative positions of the sound source and the medical device on the detector or on a display in electrical communication with the detector.

[0017] In one or more embodiments, the medical device includes a catheter or guidewire.

[0018] Another aspect of the invention relates to a method for positioning a sound source and a conduit relative to each other, the method comprising: a. introducing a conduit into a mammal, the conduit including an axis and a tip disposed at a distal end of the axis; and at least one acoustic sensor disposed on or within the axis, each acoustic sensor disposed at a corresponding distance from the distal end of the axis; b. acoustically coupling a sound source to the mammal at a location corresponding to a target location of the conduit, the sound source including a housing and a plurality of source transducers disposed within the housing; c. generating a wide beam of acoustic energy using the sound source; d. determining a measured distance between the source transducers and the at least one acoustic sensor using a detector that is in electrical or wireless communication with the at least one acoustic sensor, the measured distance being at least partially based on the Time-of-Flight (ToF) of the acoustic signal transmitted between the source transducer and each acoustic sensor; e. setting a focal length of the source transducer corresponding to the measured distance; f. generating a focused beam of acoustic energy with the sound source while moving the sound source parallel to a first axis orthogonal to the acoustic axis of the acoustic transducer, the focused beam being focused at the focal length; g. h. Monitoring the output signal of at least one acoustic sensor with a detector to determine a first maximum amplitude signal while generating a focused beam, the first maximum amplitude representing a first position relative to a first axis; h. After step g, scanning the focused beam relative to a second axis orthogonal to the acoustic axis of the acoustic transducer, with the ultrasonic source positioned at a position corresponding to the first maximum amplitude signal; i. Monitoring the output signal of at least one acoustic sensor with a detector to determine a second maximum amplitude signal while scanning the focused beam, the second maximum amplitude representing a second position relative to a second axis; j. After step h, rotating the focused beam relative to the acoustic axis; and k. Monitoring the output signal of at least one acoustic sensor with a detector to determine a third maximum amplitude signal while the focused beam is rotated, the third maximum amplitude representing a third position relative to the acoustic axis.

[0019] In one or more embodiments, the method further includes locking the sound source at a location corresponding to the first maximum amplitude signal.

[0020] Another aspect of the invention relates to a guidewire comprising a core; a coil arranged coaxially on the core; a protective coating disposed on the coil; at least one acoustic sensor disposed at a corresponding distance from the distal end of the axis; and at least one electrical conductor disposed in the protective coating, each electrical conductor electrically connecting a corresponding acoustic sensor to one or more electrical connection points in a housing attached to the proximal end of the guidewire.

[0021] In one or more embodiments, each acoustic sensor includes a piezoelectric polymer film disposed around at least a portion of the outer periphery of the core. In one or more embodiments, each acoustic sensor includes a piezoelectric polymer film disposed around at least a portion of the outer periphery of a protective film. In one or more embodiments, each acoustic sensor includes a piezoelectric polymer film disposed within the protective film. Attached Figure Description

[0022] To gain a more complete understanding of the nature and advantages of the concepts disclosed herein, reference is made to the detailed description and accompanying drawings of the preferred embodiments.

[0023] Figure 1 This is a block diagram of a system for acoustically locating a sound source relative to a duct, according to an embodiment.

[0024] Figure 2 According to one embodiment Figure 1 An isometric view of the catheter shown.

[0025] Figure 3 yes Figure 2 An enlarged view of the distal end of the catheter shown.

[0026] Figure 4A C is the cross section of the conduit axis through the first plane according to different embodiments.

[0027] Figure 5 It is a cross-section of the duct axis through a second plane according to one embodiment.

[0028] Figure 6A D is the cross section of the conduit axis through the third plane according to different embodiments.

[0029] Figure 7 yes Figure 2 A top view of the housing of the catheter shown, with the cap removed.

[0030] Figure 8 This is a flowchart of a method for positioning a sound source and a conduit relative to each other.

[0031] Figure 9 An example positioning method according to an embodiment is shown.

[0032] Figure 10 An example positioning method according to another embodiment is shown.

[0033] Figure 11 This is a flowchart of a method for positioning a sound source and a conduit relative to each other, according to another embodiment.

[0034] Figure 12 An example coordinate system is shown.

[0035] Figure 13A and 13B Example trajectories of two acoustic sensors on the duct and their respective differential signals are shown.

[0036] Figure 14 Example traces from two acoustic sensors on a duct oriented along the acoustic axis of the sound source are shown.

[0037] Figure 15 This is a block diagram of a system for acoustically locating a sound source relative to a duct, according to another embodiment.

[0038] Figure 16 This is a partially transparent side view of the guidewire according to one embodiment.

[0039] Figure 17A and 17B According to different embodiments Figure 16 The cross-section of the guide wire is shown.

[0040] Figure 18 This is a partially transparent side view of the guidewire according to another embodiment.

[0041] Figure 19A C is based on different embodiments Figure 18 The cross-section of the guide wire is shown.

[0042] Figure 20 This is a block diagram of a system for acoustically locating a sound source relative to a guidewire, according to an embodiment.

[0043] Figure 21 An exemplary embodiment is shown, in which a medical device having multiple acoustic sensors is inserted into a human kidney collection system via a ureter. Detailed Implementation

[0044] The conduit includes a shaft having one or more acoustic sensors disposed on or within the shaft and at a corresponding distance from its distal end. The acoustic sensors may include a corresponding piezoelectric polymer membrane disposed around part or all of the outer periphery of an inner or outer tube of the shaft. The outer tube is disposed on the inner tube to cover the acoustic sensors. Leads and wires for the acoustic sensors may be disposed between the inner and outer tubes.

[0045] A guidewire includes a coil, a core, and has one or more acoustic sensors disposed on or within the guidewire at a corresponding distance from the distal end of the guidewire. The acoustic sensors may include corresponding piezoelectric polymer films disposed around some or all of a protective coating of the coil or around some or all of the core.

[0046] After a catheter or guidewire is inserted or introduced into a mammal, acoustic sensors can be used to position the catheter or guidewire and the sound source relative to each other without imaging.

[0047] Figure 1 This is a block diagram of a system 10 for acoustically positioning a sound source 12 relative to a catheter 14, according to an embodiment. The sound source 12 includes a housing 16 and one or more acoustic transducers 18 disposed within the housing 16. The sound source 12 may include an acoustic treatment head that can be configured to generate acoustic energy to perform a treatment or medical procedure. The sound source 12 may be placed on the skin 20 of a mammal 22, such as a human. An acoustic transmission medium 24, such as water, a water pad, acoustic coupling oil, and / or acoustic coupling gel, may be disposed between the sound source 12 and the skin 20 (e.g., in direct physical contact) to improve acoustic transmission. The sound source 12 may be powered by a power source, an amplifier, and / or a controller 25 electrically connected to the sound source 12.

[0048] The catheter 14 includes a shaft 26 and one or more acoustic sensors 28 disposed on or within the shaft 26. The acoustic sensors 28 may be located at predetermined positions distal to the shaft 26 and / or at the tip 30 distal to the catheter 14. After the catheter 14 is introduced into the mammal 22, for example through a natural or surgical opening 32, the acoustic source 12 and the catheter 14 can be positioned and / or aligned relative to each other using an acoustic signal 34 generated by the sound source 12 and received by the acoustic sensors 28 on the catheter 14. For example, the time-of-flight (ToF) and / or amplitude (e.g., maximum value) of the acoustic signal 34 can be used to position and / or align the sound source 12 and the catheter 14. The catheter 14 may be placed within the anatomical structures of the mammal 22, such as in an anatomical passage 38 (e.g., the urethra, rectum, or blood vessel), internal organs, or another anatomical structure. The catheter 14 may be placed near a target volume 40, which may be the target of a treatment and / or medical procedure. The catheter 14 can be used to introduce guidewires, tools, acoustic enhancers (e.g., engineered microbubbles), fluids, and / or therapeutic substances into or near the target volume 40. For example, acoustic enhancers can be used to promote the fracturing of calcifications (e.g., urinary stones or kidney stones) by promoting local cavitation under low-pressure amplitude.

[0049] Acoustic sensor 28 may be electrically connected (e.g., via cable or wire 36 (typically a cable)) to detector 42 to detect and / or analyze acoustic signals (e.g., acoustic signal 34) received by acoustic sensor 28, which have been converted into electrical signals by acoustic sensor 28. Additionally or optionally, electrical signal data representing the acoustic signals received by acoustic sensor 28 may be wirelessly transmitted to detector 42. Wireless transmission may be performed using a local wireless protocol such as Bluetooth, a local wireless network such as Wi-Fi, a wide-area wireless network such as a cellular network, or another wireless transmission network or protocol.

[0050] Detector 42 may include a computer, a treatment console (e.g., a portion of a treatment console), a data acquisition board, an oscilloscope, or any other device to preprocess and / or detect the acoustic signals received by acoustic sensor 28. In some embodiments, detector 42 and controller / power supply 25 may be combined, for example, within a treatment console.

[0051] Figure 2 This is an isometric view of a conduit 14 according to one embodiment. A shaft 26 has a proximal end 201 and a distal end 202. The shaft 26 may extend from the proximal end 201 to the distal end 202 parallel to an axis 204. The shaft 26 may be flexible and / or bendable, such that it includes one or more bends and / or turns.

[0052] Housing 210 is disposed and / or connected to the proximal end 201 of shaft 26. Housing 210 may also be referred to as a connection hub or handle. Housing 210 may enclose the electrical connection between acoustic sensor 28 and cable 36. The proximal end of cable 36 may include an electrical plug 220, which may be electrically connected to detector 42. Housing 210 may also include one or more ports that connect to corresponding channels in shaft 26.

[0053] Figure 3 It corresponds to the distal end of catheter 14. Figure 2 An enlarged view of region 300. In the embodiment described, acoustic sensor 28 includes a first acoustic sensor 381 and a second acoustic sensor 382. In other embodiments, the acoustic sensor includes only the first acoustic sensor 381 or the second acoustic sensor 382. In other embodiments, acoustic sensor 28 includes more than two acoustic sensors.

[0054] The first acoustic sensor 381 includes a first piezoelectric polymer membrane 391 wound and / or disposed on the inner tube 310 of the shaft 26. The second acoustic sensor 382 includes a second piezoelectric polymer membrane 392 wound and / or disposed on the inner tube 310 of the shaft 26. The shaft 26 includes an outer tube 312 disposed on the inner tube 310. For illustrative purposes only, the outer tube 312 is shown not extending to the distal end 202 of the shaft 26 so as not to obscure the first and second sensors 381, 382. However, the outer tube 312 may extend to the distal end 202 of the shaft 26 (e.g., to the proximal end of the tip 30). The outer tube 312 may be configured to cover the first sensor 381 and the second sensor 382, ​​including the first piezoelectric polymer membrane 391 and the second piezoelectric polymer membrane 392, such that the first sensor 381 and the second sensor 382 (and the first piezoelectric polymer membrane 391 and the second piezoelectric polymer membrane 392) are between the inner tube 310 and the outer tube 312. The inner tube 310 and the outer tube 312 are coaxial.

[0055] Electrical leads 321 and 322 are disposed on the inner tube 310. The distal end of each electrical lead 321 and 322 is electrically connected to one or both of the first sensor 381 and the second sensor 382 (e.g., electrically connected to one or both of the first piezoelectric polymer film 391 and / or the second piezoelectric polymer film 392, respectively). The proximal end of each electrical lead 321 and 322 is electrically connected to one or more electrical contact pads 325. In some embodiments, the proximal end of each electrical lead 321 and 322 is electrically connected to a corresponding electrical contact pad 325. In some embodiments, more than two electrical leads 321 and 322 may be present, for example, three or more electrical leads electrically connected to one or more electrical contact pads 325. In one embodiment, three electrical leads (e.g., including electrical leads 321 and 322) and three electrical pads 325 are present, wherein each lead is electrically connected to a corresponding electrical pad 325. The wires may be electrically connected to the electrical pads 325 and electrical connection points in the housing 210. The wires can be installed between the inner conduit 310 and the outer conduit 312.

[0056] The first piezoelectric polymer film 391 and the second piezoelectric polymer film 392 comprise or are composed of piezoelectric polymers, such as polyvinylidene fluoride (PVDF), Pb(Zr,Ti)O3 (PZT), poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) copolymer, BaTiO3 / PVDF-TrFE, ZnO film, Zr2P2BrCl, M2CO2, and / or another piezoelectric polymer. Piezoelectric polymers, such as PVDF, are polarized fluoropolymers that exhibit strong and stable piezoelectric and thermoelectric activity in their polar form (e.g., β phase). Ferroelectricity is the property of spontaneously polarized electrodes that can be reversed by the application of an external electric field. This property is commonly observed in materials with non-centrosymmetric crystal structures that allow for the formation and conversion of dipoles within the crystal.

[0057] Piezoelectric polymer membranes, such as those containing or composed of PVDF, can provide ultrasonic performance with consistent cell-to-cell repeatability at low cost. PVDF membranes can provide a wide frequency bandwidth with low Q-factor and low impedance (e.g., 30–100 ohms). Furthermore, PVDF membranes are lightweight and flexible to conform to the cylindrical surface of the conduit 14 (e.g., inner tube 310). PVDF membranes can also provide excellent acoustic matching with fluids and / or biological tissues.

[0058] PVDF films are mechanically robust and are also used in structural and coating applications where piezoelectric properties are not specifically required. In one embodiment, shaft 26 (or a portion thereof) may be formed of PVDF (or another piezoelectric polymer material), and acoustic sensor 28 may be formed by depositing electrodes at certain locations on the PVDF structure.

[0059] The magnified view also shows that the tip 30 may be tapered, for example, to facilitate easy passage of the catheter 14 along or through anatomical features such as blood vessels (e.g., vascular vessels) or ureters. The tip 30 includes an opening 330 that connects to one or more channels defined in the inner tube 310.

[0060] Figure 4A It is axis 26 along Figure 3 A cross-sectional view of plane 401 is shown. The cross-section is the shaft 26 between the solder pad 325 and the proximal end 201 of the shaft 26. The cross-section shows one or more (e.g., multiple) wires 400 or other electrical conductors arranged between the inner tube 310 and the outer tube 312. In the illustrated embodiment, there are three wires 400. In other embodiments, there may be only one wire 400, two wires 400, four wires 400, or other numbers of wires. The wires 400 may be electrically connected to the corresponding solder pad 325. In some embodiments, the wires 400 may be electrically connected to more than one solder pad 325 and / or multiple wires 400 may be electrically connected to the same solder pad 325.

[0061] The conductor 400 can be electrically insulated or exposed. Furthermore, an insulating material 420 can be disposed between the inner tube 310 and the outer tube 312, and can surround each conductor 400 to provide electrical insulation to it. The insulating material 420 can also improve the mechanical strength of the shaft 26.

[0062] One or more channels 430 are defined at least by the inner diameter 410 of the inner tube 310. Channels 430 can be used to introduce guidewires, tools, acoustic intensifiers (e.g., engineered microbubbles), fluids, and / or therapeutic substances into or near a target volume. Channels 430 extend to an opening 330 at the tip 30.

[0063] The inner tube 310 has a wall 440 with an inner tube thickness defined by the difference between the outer diameter 412 and the inner diameter 410. The radial thickness of the wall 440 may have one or more local regions 442 that are thicker than the inner tube thickness. For example, a local section 444 of the wall 440 may have a larger local outer diameter or outer diameter than the outer diameter 412 (or outer diameter). The local regions 442 may be areas (e.g., extruded regions) where additional material is extruded to form the wall 400 during manufacturing. These local regions 442 increase the structural strength and / or stiffness of the inner tube 310 and may generally increase the structural strength and / or stiffness of the shaft 26. Additionally or alternatively, the local regions 442 may be provided between adjacent conductors 400 to physically separate and electrically isolate the conductors 400.

[0064] The outer tube 312 has a wall 450, the wall 450 having an outer tube thickness defined by the difference between the outer diameter 452 and the inner diameter 454 of the outer tube 312. A gap 460 is defined between the outer diameter 412 of the inner tube 310 and the inner diameter 454 of the outer tube 312. A wire 400, an insulating material 420, and a localized area 442 are disposed in the gap 460.

[0065] In other embodiments, the local region 442 may be on the wall 450 of the outer tube 312 instead of on the wall 440 of the inner tube 310, for example, as shown in the example. Figure 4B As shown, Figure 4B Shaft 26 according to another embodiment passes through Figure 3 The cross-section of plane 401 in the middle. Local region 442 increases the structural strength and / or stiffness of outer tube 312. Apart from the location of local region 442, Figure 4B The cross section shown is... Figure 4A The cross-sections shown are the same, therefore not Figure 4B All features of the cross-section shown are labeled as they are in Figure 4A In other embodiments, the local region 442 may be on the wall 450 of the outer tube 312 and the wall 440 of the inner tube 310.

[0066] In other embodiments, the local region 442 may be replaced by a spacer 462, which is constructed as a separate element and does not need to be part of the wall 450 of the outer tube 312 and / or the wall 440 of the inner tube 310, such as Figure 4C As shown. The number, geometry, and position of the local regions 442 or spacers 462 can vary, as will be apparent to those skilled in the art. Alternatively, the local regions 442 or spacers 462, or both, can be removed.

[0067] Figure 5 It is axis 26 along Figure 3 Cross-sectional view of plane 402 in the middle. Figure 5 The cross-section shown illustrates three electrical leads 321-323 disposed in the gap 460 between the wall 450 of the outer tube 312 and the wall 440 of the inner tube 310. In other embodiments, there may be more or fewer electrical leads 321-323. The partial region 442 is shown as being disposed on the wall 440, but may be on the wall 450 instead of or outside the wall 440, as described above. Alternatively, the partial region 442 may be replaced by a spacer 462 or may be removable.

[0068] Figure 5 The cross section shown in the figure is the same as Figure 4A The cross-section shown is the same, except that conductor 400 is replaced by leads 321-323, and therefore... Figure 5 Not all features of the cross-section shown are labeled as they are in Figure 4Amiddle.

[0069] Figure 6A It is axis 26 along Figure 3 The cross-sectional view of plane 403 in the middle. Figure 6A The cross-section shown illustrates a second piezoelectric polymer membrane 392 disposed within gap 460. The second piezoelectric polymer membrane 392 may be disposed around and / or cover the outer periphery of the wall 440 of the inner tube 310. In other embodiments, the second piezoelectric polymer membrane 392 may be disposed around and / or cover a portion (e.g., an arc) of the outer periphery of the wall 440, for example, within approximately 30% to approximately 75% of the outer periphery of the wall 440, including any value or range therebetween. The local region 442 and spacer 462 do not extend into the portion of shaft 26 to allow the second piezoelectric polymer membrane 392 to be disposed around and / or cover the inner tube 310 without forming an air gap and / or minimizing the air gap. Good acoustic transmission requires the absence (or minimization) of an air gap between the outer tube 312 and the sensor (e.g., the second piezoelectric polymer membrane 392). This can be achieved, for example, by filling the gap 460 with one or more materials 600 having an acoustic impedance that matches (e.g., within about 20%) the impedance of body fluids and / or tissues, which have an acoustic impedance similar to that of water. In another embodiment, the air gap can be removed or reduced by locally increasing the diameter of the inner tube 310, such that the second piezoelectric polymer film 392 is in direct physical contact with both the outer tube 312 and the inner tube 310, as... Figure 6B As shown. In another embodiment, by disposing the second piezoelectric polymer film 392 around and / or covering the inner diameter of the outer tube 312, the air gap can be removed or reduced, such as... Figure 6C As shown. The gap 460 between the second piezoelectric polymer membrane 392 and the inner tube 310 may be filled with one or more materials 610 having high acoustic impedance and / or providing an acoustically rigid interface to increase the sound pressure at the acoustic sensor. In some embodiments, the material 610 may be configured to absorb sound waves. Partial or complete absorption of sound waves (e.g., through epoxy resin) can reduce or eliminate sound wave reflection, which may be desirable in some embodiments.

[0070] In some embodiments, the two piezoelectric polymer films 392, 692 may be stacked and arranged around the wall 440 of the inner tube 310, for example as... Figure 6D As shown. One of the two piezoelectric polymer films can be reverse-biased to reduce electromagnetic interference (EMI) and increase the signal-to-noise ratio (SNR). The piezoelectric polymer films 392 and 692 can be identical or different from each other. To remove or reduce the air gap, the outer piezoelectric polymer film 692 can be in direct physical contact with the outer tube 312, such as... Figure 6BAs shown, any gap between the external piezoelectric polymer film 692 and the outer tube 312 can be made of one or more materials 600 to interact with... Figure 6A The same manner as shown is used for filling. Additionally or alternatively, any gap between the inner piezoelectric polymer membrane 392 and the inner tube 310 may be filled with one or more materials 610, such as... Figure 6C As shown. The inner and outer piezoelectric polymer films 392 and 692 can be in direct physical contact with each other. The inner piezoelectric polymer film 392 can be in direct physical contact with the inner tube 310.

[0071] The local area 442 is shown as being set on wall 440, but may be on wall 450 instead of or outside of wall 440, as above. Alternatively, the local area 442 may be replaced by or removed by spacer 462.

[0072] Figures 6A to 6D The cross section shown is... Figure 4A , 4B Or the cross-section shown in 4C is the same, except that the conductor 400 is replaced by a piezoelectric polymer film 392 and optionally a piezoelectric polymer film 692, and the insulating material 420 is replaced by a sound-permeable material 600, or the gap 460 is removed by increasing the diameter of the inner tube 310, and therefore Figures 6A to 6D Not all features of the cross-section shown are as Figures 4A to 4C It was marked like that.

[0073] Except for replacing the second piezoelectric polymer film 392 with the first piezoelectric polymer film 391 in the cross-section passing through plane 404, passing through Figure 3 The cross-section of plane 404 in the middle can be with Figures 6A to 6D All cross sections shown are identical.

[0074] Figure 7 This is a top view of housing 210, with the top cover removed to expose the interior of housing 210. Electronic device 700 is disposed within housing 210. Electronic device 700 may include a device having a corresponding housing and / or circuitry mounted on a printed circuit board (PCB) 710. For example, electrically connected to electrical contact pads 325 (… Figure 3The wire 400 can be electrically connected to the electronic device 700 (e.g., to PCB 710). The electronic device 700 may include circuitry to preprocess signals, improve the signal-to-noise ratio, and / or suppress common-mode electromagnetic interference. In some embodiments, the circuitry may include one or more signal preamplifiers, common-mode chokes, and / or common-mode suppression transformers. Wiring connections within the housing 210 (e.g., wire connections from wire 400 to the electronic device 700) may be direct to provide direct current (DC) continuity, or indirect, with capacitive and / or inductive coupling to transmit alternating current (AC) only. Furthermore, by using isolation devices, such as isolation transformers or optocouplers, circuitry can be used to connect the acoustic sensor 28 to detection circuitry (e.g., in a detector such as detector 42). Figure 1 The external detector is electrically isolated.

[0075] Optional cable 36 can be electrically connected to PCB 710 to receive electrical signals after passing through electronics 700. Therefore, housing 210 can provide the physical and electrical transition from the precision wire 400 connecting the acoustic sensor 28 to the more robust cable 36. Cable 36 can be permanently connected to housing using another connector or, for example, using strain relief device 736. Additionally or optionally, electrical signal data representing the acoustic signals received by acoustic sensor 28 can be wirelessly transmitted using wireless communication circuitry 750, which can be mounted on and / or electrically connected to PCB 710. Wireless transmission circuitry 750 can be configured to transmit using a local wireless protocol such as Bluetooth, a local wireless network such as Wi-Fi, a wide-area wireless network such as a cellular network, or another wireless transmission network or protocol.

[0076] The housing 210 may include a port 720 having an opening 722 for connection to a channel 330 in the shaft 26. The port 720 may be configured to connect to a tube or syringe, for example, using a Luer locking connector 724. The Luer locking connector 724 is shown as a concave connector, but in another embodiment it may be a convex connector. The Luer locking connector 724 can provide a leak-proof connection to a standard convex tapered connector for syringe tips and / or other fluid transfer devices.

[0077] Opening 722 can be used to insert guidewires, tools, acoustic enhancers (e.g., engineered microbubbles), fluids and / or therapeutic substances through channel 430 and from tip 30. Figure 3 The opening 330 in the target volume is placed, for example, at or near the target volume 40.

[0078] The housing 210 may include a pin 730 to releasably connect the front (not shown) and rear 740 of the housing 210. The internal space 742 of the housing 210 may be enclosed to provide a fluid seal (e.g., for liquids and / or gases) and to improve the mechanical and electrical robustness of the final assembly.

[0079] Figure 8 This is a flowchart of a method 80 for positioning sound source 12 and conduit 14 relative to each other.

[0080] In step 801, the catheter 14 is inserted into the natural or surgical opening 32 of the mammal.

[0081] In step 802, the sound source 12 is acoustically coupled to a mammal 22, such as a human. The sound source 12 may be placed directly on the mammal 22 (e.g., on the skin 20 of the mammal 22) to acoustically couple the sound source 12 to the mammal 22. Alternatively, an acoustic transmission medium 24, such as water, a water pad, acoustic coupling oil, and / or acoustic coupling gel, may be disposed between the sound source 12 and the skin 20 (e.g., in direct physical contact) to improve acoustic transmission and acoustic coupling. The sound source 12 may be acoustically coupled to the mammal 22 at a location corresponding to the target location of the introduction catheter 14.

[0082] In step 803, an acoustic signal 34 is generated using one or more acoustic transducers 18 in the sound source 12. When an acoustic signal 34 is generated using multiple (e.g., two or more) acoustic transducers 18, the acoustic signal 34 is generated sequentially using each acoustic transducer 18.

[0083] The sound source 12 may include an array or other structure of acoustic transducers 18. The array may include one (e.g., a linear array) or two or more rows of acoustic transducers 18. In some embodiments, one of the acoustic transducers 18 may be offset relative to the linear array to break the symmetry of the acoustic transducers 18.

[0084] Figure 9 An exemplary linear array of acoustic transducers 18 and an exemplary conduit 14 in sound source 12 are shown, simplified to cylinders for illustrative purposes only. Acoustic signal 34 is generated sequentially by the first and last (digits 1 and 12) acoustic elements. In other embodiments, acoustic signal 34 may be generated sequentially by other and / or additional acoustic transducers 18. In other embodiments, acoustic signal 34 is generated by only one acoustic transducer 18.

[0085] In step 804, the acoustic signal 34 is received by the acoustic sensor 28 on or within the catheter 14. For example, in Figure 9In the process, acoustic signal 34 is received by first acoustic sensor 901 and second acoustic sensor 902. When acoustic signal 34 is generated sequentially by multiple acoustic transducers 18, acoustic signal 34 is received sequentially from each acoustic transducer 18 by first acoustic sensor 901 and second acoustic sensor 902.

[0086] In step 805, the Time of Flight (ToF) of the acoustic signal 34 transmitted between the acoustic transducer 18 and the acoustic sensor 28 is determined. The ToF can be determined by a detector 42 (e.g., a computer) electrically connected, electrically communicating, and / or electromagnetically (e.g., wirelessly) to the acoustic sensor 28. The detector 42 can be electrically connected, electrically communicating, and / or electromagnetically (e.g., wirelessly) to the controller 25 and / or the source 12. Information from the detector 42 can be sent to a processing device and / or a display device.

[0087] Time of Flight (ToF) can be determined as the arrival time of the acoustic signal 34 relative to the trigger signal provided by the controller 25 at the acoustic sensor 28. Alternatively, ToF can be determined by measuring the time delay between the transmitted and received signals. Alternatively, ToF can be determined solely from the receiver signal, since the acoustic sensor 28 typically detects the acoustic signal and the EMI generated during the transmission of the acoustic signal 34 by the transmitting acoustic transducer 18, such as a treatment head. The delay between the EMI and the acoustic signal detected at the acoustic sensor 28 can be used to determine ToF.

[0088] The delay between transmitted and received signals can be measured by finding the maximum value of the cross-correlation function of the transmitted and received signals. Alternatively, the delay can be determined as the time difference between some detectable characteristic features in the transmitted and received signals. Features may include a maximum amplitude or a threshold level, for example, in the range of approximately 10% to approximately 50% of the maximum amplitude. Features may also include signal peaks, troughs, and / or zero-crossings. These features can be used individually or in combination using sequences of one or more frequencies. Furthermore, specific features can be created in the sound waves using, for example, amplitude, phase, and / or frequency modulation. Certain combinations of these techniques can be used to improve the accuracy of delay time measurements.

[0089] In another embodiment, the sensor's position can be determined by considering the time differences of arrival from different transducer elements. The difference lies in the hyperbola, which has a focal point at the transducer location. Different pairs of transducers can provide different hyperbolas. The intersection of the hyperbolas gives the sensor's position. The mathematical formula will be similar to that used in hyperbolic navigation.

[0090] In step 806, the distance between each acoustic sensor 28 and each acoustic transducer 18 is determined. This distance can be determined by multiplying the corresponding ToF by the speed of sound in soft tissue, which can be approximated by the speed of sound in water. The speed of sound in water at normal body temperature (37°C or 98.6°F) is 1524 m / s, approximately 2.6% higher than the speed of sound at room temperature (20°C).

[0091] In step 807, the conduit 14 and the sound source 12 are positioned relative to each other. The positioning resolution can vary depending on the number and / or configuration of the acoustic transducers 18, including the number of transducer elements of the acoustic transducers 18 that generate the acoustic signal 34 and / or the number of acoustic sensors 28. Note that positioning occurs without imaging, including acoustic (e.g., ultrasound) imaging. The relative position of the sound source 12 and the conduit 14 can be displayed on a display 44 that is wirelessly connected to or electrically communicates with the detector 42. Figure 1 )superior.

[0092] In some embodiments, steps 803-807 may be repeated 808, for example, during a medical procedure. Additionally or alternatively, catheter 14 may be used to monitor the amplitude and / or other characteristics of the therapeutic ultrasound (or other acoustic energy) generated by sound source 12. Catheter 14 may also be used to introduce guidewires, tools, acoustic enhancers (e.g., engineered microbubbles), fluids, and / or therapeutic substances. Additionally or alternatively, steps 803-807 may be repeated 808 until the positioning (e.g., rolling, sliding, and depth) is at a target value or within a target range. After positioning catheter 14 and sound source 12 at the target value or within a target range, positioning attachments may be used, for example, to fix or lock the position of sound source 12.

[0093] Figure 9 An example positioning method is illustrated. Reference axis 913 is positioned along the surface of an example linear array of acoustic transducers 18 of sound source 12. Lines 921 and 922 represent radial distances along corresponding radial lines from reference axis 913 to the first acoustic sensor 901 and the second acoustic sensor 902 on conduit 14. Lines 921 and 922 are orthogonal to reference axis 913 and oriented at respective angles 925 and 926, which may be the same or different depending on the orientation of conduit 14. Angles 925 and 926 represent the angular coordinates of the first acoustic sensor 901 and the second acoustic sensor 902 in a cylindrical coordinate system with longitudinal axis 913.

[0094] Measuring the Time-of-Flight (ToF) of the acoustic signals 34 from the acoustic transducer 18 to the first acoustic sensor 901 and the second acoustic sensor 902 allows determination of the distances (e.g., reference axis 913) between the first acoustic sensor 901 and the second acoustic sensor 902 and the acoustic transducer 18. Any pair of acoustic transducers 18 can be used to determine the following two coordinates of the first acoustic sensor 901 and the second acoustic sensor 902: axial coordinates 923 and 924 along the reference axis 913 and radial distances 921 and 922 from the reference axis 913, respectively. For example, the distances from the acoustic elements 1 and 12 of the transducer 18 to the first acoustic sensor 901 and the second acoustic sensor 902 are shown by dashed lines 917-920. Considering the triangle formed by lines 917 and 919 and the line connecting the acoustic elements 1 and 12 of the transducer 18 (e.g., line segment 913), the radial distance 921 between the first acoustic sensor 901 and the reference axis 913 can be found. Similarly, considering the triangle formed by lines 918, 920 and the lines connecting acoustic elements 1 and 12 of transducer 18, the radial distance 922 between the second acoustic sensor 902 and the reference axis 913 can be found.

[0095] Figure 10 An example positioning method according to another embodiment is shown. Figure 10 A cylindrical coordinate system is shown with a reference axis 1013 along or through the conduit 14, wherein the conduit 14 remains stationary while the acoustic transducer 18 is movable. Lines 1021 and 1022 represent the radial distances from the reference axis 1013 to the acoustic elements 1 and 12 of the transducer 18 along the respective radial lines. The distances from the acoustic elements 1 and 12 of the transducer 18 to the first acoustic sensor 901 and the second acoustic sensor 902 are shown by dashed lines 1017-1020. The radial distance 1021 from the reference axis 1013 to the acoustic element 1 can be determined by the triangle formed by lines 1017, 1018 and line 1023 (e.g., a segment of the reference axis 1013) connecting the first acoustic sensor 901 and the second acoustic sensor 902. Similarly, the radial distance 1022 from the reference axis 1013 to the acoustic element 12 can be determined by the triangle formed by lines 1019, 1020, and 1023. Lines 1021 and 1022 are typically skewed lines. That is, the triangle formed by lines 1017, 1018, and 1023 does not necessarily lie in the same plane as the triangle formed by lines 1019, 1020, and 1023.

[0096] Figure 9 and 10A potential problem with the illustrated localization method is that the symmetry of the linear array of acoustic transducers 18 may make it difficult to resolve all three coordinates of the corresponding positions of each acoustic sensor 901, 902. All elements of the linear array transducers are arranged along a line. The symmetry of this linear array arrangement can cause problems with full three-dimensional position resolution. For example, see [reference to...] Figure 9 The following explanation is provided. Measuring the distance between each acoustic sensor 901, 902 and any pair of acoustic transducers 18 allows for the determination of only two independent coordinates. In a cylindrical coordinate system, these coordinates are the position along a reference (or longitudinal) axis 913 and the radial distance from the reference axis 913 (e.g., along lines 921, 922). For the first acoustic sensor 901, for example, the radial distance from the reference axis 913 is shown as 921. Dashed lines 917, 919 connect the first acoustic sensor 901 to acoustic elements 1 and 12, respectively, and represent the corresponding distances between the first acoustic sensor 901 and acoustic elements 1 and 12. Considering any other collinear elements (e.g., any one of acoustic elements 2-11), the angular coordinate 925—the third independent coordinate of the cylindrical system—is not distinguished because all transducer elements lie on the same line and in the same plane as lines 917 and 919. Additional information is needed to determine the angle 925.

[0097] In embodiments, the problem associated with the symmetry of the linear array arrangement can be addressed using a 2D or 3D arrangement of acoustic sensors 28 (e.g., acoustic sensors 901, 902) and / or acoustic transducers 18. For example, the conduit 14 may have three or more non-collinear acoustic sensors 28. Alternatively, the acoustic transducers 18 may be arranged on a 2D surface or a 3D geometry. Note that to address the symmetry problem, the arrangement is achieved by using a symmetry perpendicular to the longitudinal axis of the linear array (…). Figure 9 Separating, splitting, or adding one or more elements along the direction of the reference axis 913 in the linear array is sufficient to break the symmetry of the linear array. For example, the acoustic transducers 18 can be arranged in a two-dimensional or three-dimensional array. Alternatively, one or more additional acoustic transducers 18 can be added to the linear array in a non-collinear manner.

[0098] Another localization method employs a known acoustic field distribution generated by a given transducer. Matching the known acoustic distribution with measurements of acoustic signals from a duct sensor (e.g., acoustic sensor 28) allows for the determination of the duct's position within the acoustic field. An example of this general approach is using known angular correlations of the acoustic signals to evaluate a third independent coordinate. Figure 9 For example, such a third coordinate is the angular coordinates 925 and 926 in a cylindrical coordinate system. Figure 9As shown, the linear array of acoustic transducers 18 has a finite thickness in the direction perpendicular to the reference axis 913. Therefore, these elements can generate a sound field with a specific pattern characterized by angle dependence. Angular dependence can affect the acoustic amplitude and / or duration of the acoustic signal. Matching the angular dependence to acoustic signal measurements allows for the determination of angular coordinates 925, 926.

[0099] Another positioning method involves separating the acoustic sensors 28 (e.g., acoustic sensors 901, 902) mounted on conduit 14 at a known distance. This distance provides an additional constraint to reduce positioning ambiguity. For example, consider... Figure 9 The diagram shows a duct with two sensors and a linear array transducer. The positions of the first acoustic sensor 901 and the second acoustic sensor 902 are described by axial coordinates 923, 924, radial distances 921, 922, and angles 925, 926, respectively. As described above, due to the symmetry of the linear array transducer, Time-of-Flight (ToF) measurements allow for the determination of the axial coordinates 923, 924 and radial distances 921, 922, rather than the angles 925, 926. The known distance between the first and second acoustic sensors 901, 902 allows for the evaluation of the angle between the reference axis 913 and the duct direction to determine the angles 925, 926.

[0100] Note that when the conduit 14 includes only one acoustic sensor 28, the orientation of the conduit 14 is difficult to determine. The distance between the conduit 14 and the sound source 18 can be determined. (Refer to...) Figure 9 Assuming that the conduit 14 includes only the first acoustic sensor 901, when at least two acoustic transducers 18 generate acoustic signals 34, the radial distance along the radius line 921 and the axial coordinate 923 of the first acoustic sensor 901 (e.g., of the radius line 921) can be determined. The angle 925 of the first acoustic sensor 901 (e.g., the angle of the radius line 921) can be determined, for example, using the angular dependence of the acoustic signals on the orientation of the acoustic transducers 18, as described above.

[0101] In some embodiments, detector 42 may use positioning data to generate an output signal that enables robot locator 1510 ( Figure 15 The sound source 12 is positioned relative to the conduit, for example, aligned with the sound source 12 relative to the conduit 14. The robot locator 1510 and the detector 42 can communicate wirelessly, electrically, or both.

[0102] Figure 11 This is a flowchart of a method 1100 for positioning a sound source 12 and a conduit 14 relative to each other, according to another embodiment.

[0103] In step 1101, the catheter 14 is inserted into the natural or surgical opening 32 of the mammal.

[0104] In step 1102, the sound source 12 is acoustically coupled to a mammal 22, such as a human. The sound source 12 may be placed directly on the mammal 22 (e.g., on the skin 20 of the mammal 22) to acoustically couple the sound source 12 to the mammal 22. Alternatively, an acoustic transmission medium 24, such as water, a water pad, acoustic coupling oil, and / or acoustic coupling gel, may be disposed between the sound source 12 and the skin 20 (e.g., in direct physical contact) to improve acoustic transmission and acoustic coupling.

[0105] In step 1103, a wide-beam percutaneous ultrasound is generated to determine the skin-to-catheter distance by measuring the Time-of-Flight (ToF) between the acoustic transducer 18 and the acoustic sensor 28. In step 1104, the ToF is used to determine the distance between the acoustic transducer 18 and the acoustic sensor 28. In step 1105, the focal length of the sound beam generated by the acoustic transducer 18 is set based on the measured distance (e.g., the skin-to-catheter distance).

[0106] In step 1106, the acoustic transducer 18 generates an acoustic signal 34 focused at the focal length determined in step 1104. When the sound source 12 includes only one acoustic transducer 18, the acoustic transducer 18 may include an adjustable acoustic lens and / or mechanical means to change the focal length. When the sound source 12 is parallel to... Figure 12 As the Y-axis of the XYZ coordinate system shown moves or translates, the sound source 12 is aligned with the conduit 14 by searching for a first maximum amplitude signal measured by the acoustic sensor 28. The first maximum amplitude signal corresponds to a first positioning, such as a first coordinate (e.g., relative to the Y-axis), and the corresponding position of the sound source 12 on the mammal 22 (e.g., relative to the Y-axis). In step 1107, once the sound source 12 is aligned with the acoustic sensor 28, the sound field on the sound source 12 is switched to a scanning focused beam while the sound source 12 remains at the position along the Y-axis corresponding to the first maximum amplitude signal. The scanning focused beam can be performed by moving the sound source 12 parallel to the Y-axis and / or by electronically changing the focus position (e.g., by changing the relative phase of the acoustic transducers 18 in the phased array). This will be along or parallel to... Figure 12 The X-axis scanning beam of the XYZ coordinate system is shown.

[0107] In step 1108, when the signal on acoustic sensor 28 is maximized, sound source 12 rotates about the transducer axis to find orientation, indicating good alignment of the treatment head with the catheter in the ureter. In step 1109, the aligned sound source 12 is locked in place (e.g., at the position corresponding to the first maximum amplitude signal) to perform the treatment procedure. Sound source 12 can be locked in place using a mechanical means. Note that positioning occurs without imaging, including acoustic (e.g., ultrasound) imaging.

[0108] Figure 12An example Cartesian coordinate system with three orthogonal coordinates X, Y, and Z is shown. The X-axis is oriented along the longitudinal axis of the sound source 12 (e.g., the treatment head). The Z-axis is oriented along the axis of symmetry of the sound source 12. The distal end 202 of the catheter 14 ( Figure 2 It is located at a distance Z from the sound source, which is 12.

[0109] Figure 13A and 13B Example traces 1301A, 1301B, 1302A, and 1302B of two acoustic sensors 28 on catheter 14 are shown, along with their respective differential signals 1303A and 1303B, demonstrating the alignment process between the sound source 12 and catheter 14. One acoustic sensor 28 is mounted approximately 3 cm from the catheter tip (traces 1301A and 1301B), and the other is closer to the tip (traces 1302A and 1302B). Catheter 14 is aligned along the X-axis of the sound source 12 (… Figure 12 The acoustic sensor 28 was positioned approximately 12 cm (Z-axis) from the sound source 12, corresponding to a Time-of-Flight (ToF) of approximately 80 μs. The sound source 12 emitted a 10-cycle tonal pulse train at a center frequency of 450 kHz. The acoustic signal received by the acoustic sensor 28 was observed within a time window of 80–120 μs. Figure 13A In the diagram, trace 1301A shows a larger acoustic signal amplitude than trace 1302A detected by the transducer at the catheter tip. A 3 cm displacement of the treatment head along the X-axis decreases trace 1301B and increases trace 1302B, indicating alignment of the treatment head 12 with the tip of the catheter 14. Signal traces 1303A and 1303B show differential signals calculated by taking the difference between the signals received by the two sensors 1301 and 1302, thus demonstrating a method for reducing EMI induced during emission from the sound source 12.

[0110] Figure 14 Signals from acoustic sensors 28 (traces 1401, 1402) are shown. These sensors are mounted on a catheter 14 oriented along the Z-axis of the sound source 12, approximately 3 cm apart. The propagation time of the acoustic signal over the 3 cm distance is 20 μs. This time delay, observed between traces 1401 and 1402, indicates that the Z-axis of the treatment head is oriented such that the acoustic axis (Z-axis, Figure 12Along the length of catheter 14. Furthermore, the arrival time of acoustic sensor 28 positioned closer to the tip 30 of catheter 14 (trace 1402) is shorter than that of acoustic sensor 28 positioned further away from the tip 30, indicating that the tip 30 of catheter 14 is oriented towards sound source 12. Visual confirmation of this orientation of catheter 14 demonstrates the proposed alignment method. Trace 1403 represents a differential signal, indicating a method for reducing EMI simultaneously induced on both acoustic sensors 28 during treatment head emission (approximately 0–20 μs). Sound source 12 emits a 10-cycle burst of sound with a center frequency of 450 kHz. The acoustic signal received by acoustic sensor 28 is observed within a time window of 40–100 μs, corresponding to the ToF of the sound wave from sound source 12 to acoustic sensor 28.

[0111] The catheter 14, equipped with an acoustic sensor 28, can be used for guidance in medical procedures. The catheter 14 can be inserted through a small incision in the skin or through a natural opening in the body. Such applications include, for example, biopsies of various organs or percutaneous access to the kidney. For percutaneous access, the catheter 14 can be inserted through the ureter and can have a preset shape that will ensure a specific location of the catheter 14 in the kidney. For example, the catheter 14 can be designed such that it preferably has a certain shape that tends to be positioned in the lower pole of the kidney. The ultrasound source 12 can include a guide clamp for a guide needle, which can be used in medical procedures such as biopsies or percutaneous nephrolithotomy (PCNL). The guide clamp can be adjustable to orient the catheter 14 at a localized location. The system can determine the depth of needle insertion, which can be the same as a measured depth or the distance between the sound source 12 and the catheter 14, and can ensure that the needle avoids blood vessels, a typical problem and / or complication in percutaneous access procedures. A significant advantage of all the potential applications of catheters with acoustic sensors is the avoidance or minimization of the use of harmful X-ray radiation currently used for guidance in these procedures.

[0112] Another unique advantage of the catheter 14 with acoustic sensor 28 is that the device provides an absolute measurement of the sound pressure in the treatment area. This is important because sound transmission is typically affected by various factors, such as acoustic impedance mismatches at various interfaces, low sound transmission through ribs and bones, differences in sound wave attenuation in different types of tissues, and the presence of air or cavitation along the acoustic pathway. Due to these factors, the actual sound pressure delivered to the treatment area is often unknown. This weakness can be overcome by using the catheter 14 with acoustic sensor 28.

[0113] Figure 15 This is a block diagram of a system 1500 for acoustically locating a sound source 12 relative to a conduit 14, according to another embodiment. System 1500 and system 10 ( Figure 1Similar to the previous system, except that in system 1500, robot locator 1510 is electromechanically connected to sound source 12. Detector 42 can send an output control signal to robot locator 1510, causing robot locator 1510 to locate sound source 12 in response to the positioning of sound source 12 and conduit 14 relative to each other. For example, robot locator 1510 can be aligned with sound source 12 relative to conduit 14. Detector 42 and robot locator 1510 can be electrically and / or wirelessly connected.

[0114] Figure 16 This is a partially transparent side view of a guidewire 1600 according to one embodiment. The guidewire 1600 includes a core 1610, an optional coil 1620, and one or more acoustic sensors 1628. In some embodiments, the coil 1620 may be removed. The core 1610 and the coil 1620 are coaxial and extend from the proximal end to the distal end of the guidewire 1600. The acoustic sensor 1628 may be located at a predetermined position from the distal end of the guidewire 1600 and / or from the tip 1630 of the distal end of the catheter 1600.

[0115] Acoustic sensor 1628 is located between core 1610 and coil 1620, and is disposed around at least a portion of core 1610. Acoustic sensor 1628 is electrically connected to lead and / or wire 1640. Wire and / or wire 1640 may be electrically connected to one or more electrical connection points in housing 1650, which is attached to the proximal end of guide wire 1600. It should be noted that guide wire 1600 is not shown to scale, and in practice housing 1650 will be further away from tip 1630 and acoustic sensor 1628 than shown.

[0116] The conductor and / or wire 1640 may be disposed or embedded in a protective coating 1660 covering the outer surface of the guide wire 1600, such that the conductor and / or wire 1640 extends parallel to the core 1610. The coil 1620 may be disposed or embedded in the protective coating 1660. In another embodiment, the core 1610 may be hollow, and the conductor and / or wire 1640 may pass through channels in the core 1610.

[0117] Acoustic sensor 1628 may be the same as acoustic sensor 28. Alternatively or additionally, housing 1650 may be the same as housing 210.

[0118] Figure 17A It is according to one embodiment of the passage Figure 16 The cross-section of the guide wire 1600 in the plane 1601. The acoustic sensor 1628 includes a piezoelectric polymer membrane 1692 disposed around at least a portion of the outer periphery of the core 1610. The piezoelectric polymer membrane 1692 may be the same as the piezoelectric polymer membrane 392. In some embodiments, the acoustic sensor 1628 may include two piezoelectric polymer membranes (e.g., as shown in Figure 1628). Figure 6D (As shown).

[0119] To reduce or eliminate the air gap between the protective coating 1660 and the sensor 1628 (e.g., the piezoelectric polymer film 1692), the gap 1662 between the protective coating 1660 and the sensor 1628 can be filled with one or more materials 1670 having an acoustic impedance that matches the impedance of body fluids and / or tissues (e.g., within about 20%), and having an acoustic impedance similar to that of water. Material 1670 can be the same as material 600. In another embodiment, the air gap can be removed or reduced by increasing the diameter of the core 1610 and / or by increasing the thickness of the protective coating 1660, such that the piezoelectric polymer film 1692 is in direct physical contact with the protective coating 1660 and the core 1610, as shown below. Figure 17B As shown.

[0120] 1600 guide wire passes through Figure 16 The cross section of plane 1602 in the middle can be with Figure 17A The cross-section shown is the same as, or the same as, the cross-section shown. Figure 17B The cross sections shown are the same, although the diameter of the core 1610 may be smaller in the cross section passing through plane 1602 than in the cross section passing through plane 1601.

[0121] Figure 18 This is a partially transparent side view of guidewire 1800 according to another embodiment. Guidewire 1800 is the same as guidewire 1600, except that in guidewire 1800, acoustic sensor 1628 is disposed on or within protective coating 1660.

[0122] Figure 19A It is according to one embodiment of the passage Figure 18 The cross-section of the guide wire 1800 in the plane 1801. The acoustic sensor 1628 includes a piezoelectric polymer film 1692 disposed on the outer surface of the protective coating 1660. The piezoelectric polymer film is disposed around at least a portion of the outer periphery of the protective coating 1660. The gap 1962 between the protective coating 1660 and the core 1610 may be filled with one or more materials 1970 having high acoustic impedance and / or providing an acoustically rigid interface to increase the sound pressure at the acoustic sensor 1628. In some embodiments, the material 1970 may be configured to absorb sound waves. Partial or complete absorption of sound waves (e.g., through epoxy resin) may reduce or eliminate the reflection of sound waves, which may be desirable in some embodiments. The material 1970 may be the same as the material 610.

[0123] In some embodiments, the acoustic sensor 1628 may include two piezoelectric polymer films (e.g., as shown in the figure). Figure 6D (As shown).

[0124] Figure 19BIt is according to another embodiment of crossing Figure 18 The cross-section of the guide wire 1800 in the plane 1801. The acoustic sensor 1628 includes a piezoelectric polymer film 1692 disposed or embedded in a protective coating 1660. The piezoelectric polymer film is disposed around at least a portion of the protective coating 1660. The gap 1962 may be filled with one or more materials 1970.

[0125] Figure 19C It is according to another embodiment of crossing Figure 18 The cross-section of the guide wire 1800 in the plane 1801. The acoustic sensor 1628 includes a piezoelectric polymer film 1692 disposed on the inner surface of the protective coating 1660. The piezoelectric polymer film is disposed around at least a portion of the outer periphery of the inner diameter of the protective coating 1660. The gap 1964 between the piezoelectric polymer film 1692 and the core 1610 can be filled with one or more materials 1970.

[0126] 1800 guidewires Figure 18 The cross-section of plane 1802 in the middle can be compared with Figure 19A The cross-sections shown in -C are identical, although the diameter of the core 1610 may be smaller in the cross-section through plane 1602 than in the cross-section through plane 1601.

[0127] Figure 20 This is a block diagram of a system 2000 for acoustically locating a sound source 12 relative to a guidewire 2010, according to an embodiment. System 2000 is identical to system 10 and / or system 1500, except that in system 10 and 1500, the catheter 14 is replaced with guidewire 2010. Guidewire 2010 may be the same as guidewire 1600 or guidewire 1800.

[0128] The sound source 12 and guide wire 2010 can be used according to method 80 ( Figure 8 ) or according to method 1100 ( Figure 11 They are positioned relative to each other, wherein catheter 14 is replaced by guidewire 2010.

[0129] Figure 21 One embodiment is shown in which a medical device 2100 having a plurality of acoustic sensors 2102 is inserted into a collection system of a human kidney 2120 via a ureter 2110. The medical device 2100 may be a catheter (e.g., catheter 14), a guidewire (e.g., guidewires 1600, 1800), or another medical device. The acoustic sensors 2102 may be acoustic sensors 28, 1628, and / or 1828.

[0130] When fully inserted, the medical device 2100 is configured to coil or unfold to receive a predetermined shape, such as forming a coiled structure of a predetermined shape in the kidney 2120 or at another target location. The predetermined shape determines the relative position of the acoustic sensor 2102 to avoid potential ambiguity regarding the sensor's position within the kidney 2120. An external sound source 12, acoustically coupled to the patient's skin 2112, generates an acoustic signal 2134 received by the acoustic sensor 2102 to establish and / or determine the relative position of the sound source 12 and the acoustic sensor 2102 within the kidney 2120, for example, using a detector 42. The acoustic signal 2134 may be the same as the acoustic signal 34.

[0131] After determining the relative positions of the sound source 12 and the acoustic sensor 2102 within the kidney 2120, a needle 2140 or a similar medical device can now be inserted into the kidney 2120 (e.g., into the renal calyx or renal wall), for example, to perform a percutaneous insertion procedure under the acoustic guidance of the sound source 12 and the acoustic sensor 2102, as disclosed herein. The relative position and orientation (e.g., angle) of the needle 2140 relative to the sound source 12 are known, for example, using a needle guide or needle holder 2142, which may have an adjustable insertion angle for the needle 2140. The method is easy to perform and does not require special skills, such as an acoustic spectrometer. This method requires neither an ultrasound imaging system nor harmful ionizing radiation imaging, such as X-ray imaging.

[0132] The present invention should not be considered limited to the specific embodiments described above. After reading this disclosure, those skilled in the art will readily understand the various modifications, equivalents, and structures applicable to the invention. The above embodiments can be implemented in various ways. One or more aspects and embodiments relating to the execution of a process or method can be performed or controlled using program instructions executable by a device (e.g., a computer, processor, or other device).

[0133] In this regard, various inventive concepts can be embodied in a non-transient computer-readable storage medium (or multiple non-transient computer-readable storage media) encoded with one or more programs (e.g., any suitable type of computer memory, including transient or non-transient digital memory cells, circuit configurations in field-programmable gate arrays or other semiconductor devices, or other tangible computer storage media), which, when executed on one or more computers or other processors, performs one or more methods implementing the various embodiments described above. When implemented as software (e.g., as an application program), the software code can execute on any suitable processor or set of processors, whether provided in a single computer or distributed across multiple computers.

[0134] Furthermore, it should be understood that, as a non-limiting example, a computer can be implemented in any of a variety of forms, such as a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer. Additionally, a computer can be embedded in a device that is not typically considered a computer but has appropriate processing capabilities, including a personal digital assistant (PDA), a smartphone, or any other suitable portable or fixed electronic device.

[0135] Furthermore, the computer may have one or more communication devices that can be used to interconnect the computer to one or more other devices and / or systems, such as one or more networks of any suitable form, including local area networks (LANs) or wide area networks (WANs), such as enterprise networks, and intelligent networks (INs) or the Internet. Such networks may be based on any suitable technology and may operate in accordance with any suitable protocol, and may include wireless or wired networks.

[0136] In addition, a computer may have one or more input devices and / or one or more output devices. These devices are particularly useful for presenting a user interface. Examples of output devices that can be used to provide a user interface include a printer or monitor for visual presentation of output, and a speaker or other sound-generating device for audible presentation of output. Examples of input devices that can be used for a user interface include a keyboard and pointing devices such as a mouse, touchpad, and digitizer. As another example, a computer may receive input information through speech recognition or in other audible formats.

[0137] One or more non-transitory computer-readable media may be transportable, such that one or more programs stored thereon may be loaded onto one or more different computers or other processors to implement one or more of the aspects described above. In some embodiments, the computer-readable medium may be a non-transitory medium.

[0138] The terms “program,” “application,” and “software” are used herein in a general sense to refer to any type of computer code or set of computer-executable instructions that can be used to program a computer or other processor to implement the various aspects described above. Furthermore, it should be understood that, according to one aspect, one or more computer programs that perform the methods of this application during execution do not need to reside on a single computer or processor, but can be distributed in a modular manner among multiple different computers or processors to implement the various aspects of this application.

[0139] Computer-executable instructions can take many forms, such as program modules, and can be executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or distributed as needed.

[0140] Furthermore, data structures can be stored in any suitable form on a computer-readable medium. For simplicity, a data structure can be represented as having fields that are related by their position within the data structure. Such relationships can also be implemented by assigning storage to fields with positions that convey the relationships between the fields in a computer-readable medium. However, any suitable mechanism can be used to establish relationships between information in the fields of a data structure, including by using pointers, labels, or other mechanisms that establish relationships between data elements.

[0141] Therefore, this disclosure and claims include new and novel improvements to existing methods and techniques that are neither previously known nor implemented to achieve the aforementioned useful results. Users of the methods and systems will derive significant benefits from the functionality now possible due to the specific modifications described herein that result in the effects on the system and its output to the user. It is anticipated that significantly improved operation can be achieved in implementing the claimed invention by using the technical components described herein.

[0142] Moreover, as described, some aspects can be embodied as one or more methods. Actions performed as part of a method can be ordered in any suitable manner. Thus, embodiments can be constructed in which actions are performed in a different order than those illustrated, which may include performing certain actions simultaneously, even if they are shown as sequential actions in the illustrative embodiments.

Claims

1. A catheter comprising: a shaft; a tip disposed at a distal end of the shaft; at least one acoustic sensor disposed on or in the shaft, each acoustic sensor disposed at a respective distance from the distal end of the shaft; and at least one electrical conductor disposed on or in the shaft, each electrical conductor electrically connecting a respective acoustic sensor to one or more electrical connection points in a housing attached to a proximal end of the shaft.

2. The catheter of claim 1, wherein each acoustic sensor comprises a piezoelectric polymer film disposed around at least a portion of an outer circumference of the shaft.

3. The catheter of claim 2, wherein the piezoelectric polymer film comprises polyvinylidene fluoride.

4. The catheter of claim 2, wherein: the shaft comprises an inner tube and an outer tube, the respective piezoelectric polymer film is disposed around at least a portion of an outer circumference of the inner tube, and the at least one electrical conductor is disposed between the inner tube and the outer tube.

5. The catheter of claim 4, wherein: the inner tube is defined by a wall having an inner wall thickness, and one or more regions of the wall have an increased thickness compared to the inner wall thickness.

6. The catheter of claim 4, wherein: the outer tube is defined by a wall having an outer wall thickness, and one or more regions of the wall have an increased thickness compared to the outer wall thickness.

7. The catheter of claim 4, wherein a spacer is disposed between the inner tube and the outer tube.

8. The catheter of claim 1, wherein the one or more electrical connection points are electrically connected to a cable extending through the housing.

9. The catheter of claim 8, wherein the one or more electrical connection points are formed on a printed circuit board disposed in the housing.

10. The catheter of claim 8, further comprising wireless communication circuitry electrically connected to the one or more electrical connection points.

11. The catheter of claim 1, wherein the housing comprises a port having a hole aligned with a central channel of the shaft.

12. The catheter of claim 1, wherein the at least one acoustic sensor comprises a first acoustic sensor and a second acoustic sensor, the first and second sensors separated by a predetermined distance.

13. A method for locating a sound source and a medical device relative to one another, the method comprising: a. introducing the medical device into a mammal; b. acoustically coupling the sound source to the mammal at a location corresponding to a target location of the medical device, the sound source comprising a housing and a source transducer disposed in the housing; c. producing an acoustic signal with the source transducer; d. receiving the acoustic signal with an acoustic sensor on or in the medical device, the acoustic sensor in electrical or wireless communication with a detector; e. determining a time of flight (ToF) of the acoustic signal transmitted between the source transducer and the acoustic sensor with the detector; ​ f. determining, with the detector and using the ToF, a distance between the source transducer and the acoustic sensor; and g. positioning, with the detector, the acoustic source and the medical device relative to each other in real time based at least in part on the distance between the source transducer and the acoustic sensor.

14. The method of claim 13, wherein: the acoustic sensor is a first acoustic sensor, the medical device includes at least a second acoustic sensor, and the method further comprises: receiving, with the first acoustic sensor and the second acoustic sensor, the acoustic signal; determining, with the detector, a first ToF of the acoustic signal transmitted between the source transducer and the first acoustic sensor; determining, with the detector, a second ToF of the acoustic signal transmitted between the source transducer and the second acoustic sensor; determining, with the detector and using the first ToF, a first distance between the source transducer and the first acoustic sensor; determining, with the detector and using the second ToF, a second distance between the source transducer and the second acoustic sensor; and positioning the acoustic source and the medical device relative to each other based at least in part on the first distance and the second distance.

15. The method of claim 13, wherein: the medical device includes a plurality of acoustic sensors, the acoustic source includes a plurality of source transducers, and the method further comprises: sequentially generating the acoustic signal with at least a first source transducer and a second source transducer of the plurality of source transducers; receiving the acoustic signal with each acoustic sensor; determining a respective ToF of the acoustic signal transmitted between (a) each source transducer of at least the first source transducer and the second source transducer and (b) each acoustic sensor; determining a respective distance between (a) each source transducer of at least the first source transducer and the second source transducer and (b) each acoustic sensor using each ToF; and positioning the acoustic source and the medical device relative to each other based at least in part on the respective distances.

16. The method of claim 13, wherein: the position is a first position, and the method further comprises: after performing at least steps b-f while the acoustic source is at the first position, moving the acoustic source to a second position and repeating steps b-f while the acoustic source is at the second position to improve resolution of positioning the acoustic source and the medical device relative to each other compared to performing positioning while the acoustic source is at only the first position.

17. The method of claim 13, wherein: the medical device includes a catheter, the catheter is introduced into an organ, and the method further comprises: introducing, with the catheter, an acoustic enhancer proximal to the calcification; applying acoustic energy with the acoustic source; and generating cavitation with the acoustic energy and the acoustic enhancer to break down at least a portion of the calcification.

18. The method of claim 13, further comprising adjusting a position of the acoustic source with a robotic positioner in communication with the detector based on a positioning of the acoustic source and the medical device relative to each other.

19. The method of claim 13, further comprising displaying a relative position of the acoustic source and the medical device on the detector or a display in electrical communication with the detector.

20. The method of claim 13, wherein the medical device comprises a catheter or a guidewire.

21. A method for positioning an acoustic source and a catheter relative to each other, the method comprising: a. introducing the catheter into a mammal, the catheter comprising: a shaft and a tip disposed at a distal end of the shaft; and at least one acoustic sensor disposed on or in the shaft, each acoustic sensor disposed at a respective distance from the distal end of the shaft; b. acoustically coupling the acoustic source to the mammal at a location corresponding to a target location of the catheter, the acoustic source comprising a housing and a plurality of source transducers disposed in the housing; c. generating a wide acoustic energy beam with the acoustic source; d. determining a measured distance between the source transducers and the at least one acoustic sensor with a detector in electrical or wireless communication with the at least one acoustic sensor, the measured distance based at least in part on a time of flight (ToF) of an acoustic signal transmitted between the source transducers and each acoustic sensor; e. setting a focal distance of the source transducers corresponding to the measured distance; f. generating a focused beam of acoustic energy with the acoustic source while moving the acoustic source parallel to a first axis orthogonal to an acoustic axis of the acoustic transducers, the focused beam focused at the focal distance; g. monitoring an output signal of the at least one acoustic sensor with the detector to determine a first maximum amplitude signal when the focused beam is generated, the first maximum amplitude indicative of a first positioning relative to the first axis; h. after step g, scanning the focused beam relative to a second axis orthogonal to the acoustic axis of the acoustic transducers, the ultrasound source located at a position corresponding to the first maximum amplitude signal; i. monitoring the output signal of the at least one acoustic sensor with the detector to determine a second maximum amplitude signal while the focused beam is scanned, the second maximum amplitude indicative of a second positioning relative to the second axis; j. after step h, rotating the focused beam relative to the acoustic axis; and k. monitoring the output signal of the at least one acoustic sensor with the detector to determine a third maximum amplitude signal while the focused beam is rotated, the third maximum amplitude indicative of a third positioning relative to the acoustic axis.

22. The method of claim 21, further comprising locking the acoustic source at a position corresponding to the first maximum amplitude signal.

23. A guidewire, comprising: a core; a coil coaxially disposed on the core; a protective coating disposed on the coil; at least one acoustic sensor disposed at a respective distance from the distal end of the shaft; and at least one electrical conductor disposed in the protective coating, each electrical conductor electrically connecting a respective acoustic sensor to one or more electrical connection points in a housing attached to the proximal end of the guidewire.

24. The guidewire of claim 23, wherein each acoustic sensor comprises a piezoelectric polymer film disposed around at least a portion of an outer circumference of the core.

25. The guidewire of claim 23, wherein: Each acoustic sensor comprises a piezoelectric polymer film disposed around at least a portion of an outer circumference of the protective film.

26. The guidewire of claim 23, wherein each acoustic sensor comprises a piezoelectric polymer film disposed in the protective film.

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