WO2022132729A1

WO2022132729A1 - Transducer ramp for transducer mounted on a medical device

Info

Publication number: WO2022132729A1
Application number: PCT/US2021/063256
Authority: WO
Inventors: Steve S. Khalaj; Marc COMTOIS; Sung H. Lee; Samin Askarian
Original assignee: Avent, Inc.
Priority date: 2020-12-17
Filing date: 2021-12-14
Publication date: 2022-06-23

Abstract

A transducer support structure including one or more ramps or angled walls, where the transducer support structure is configured to house an electronic part within a nest, is provided. An invasive medical device that includes the transducer support structure defining the nest and an invasive medical device that includes the transducer support structure defining the nest and that houses an electronic part (e.g., a transducer assembly) are also provided.

Description

TRANSDUCER RAMP FOR TRANSDUCER MOUNTED ON A MEDICAL DEVICE

RELATED APPLICATIONS

The present application claims priority to United States Patent Application Serial No. 63/126,915, filed on December 17, 2020, the entire contents of which are incorporated herein by reference.

FIELD

The present disclosure relates generally to the placement of transducers on medical articles, such as needles, catheters, cannulas, and/or stylets, for use with, for example, autonomous ultrasound imaging systems.

BACKGROUND

Detection of anatomical objects using medical imaging is an essential step for many medical procedures, such as regional anesthesia nerve blocks, and is becoming the standard in clinical practice to support diagnosis, patient stratification, therapy planning, intervention, and/or follow-up. Various systems based on traditional approaches exist for anatomical detection and tracking in medical images, such as computed tomography (CT), magnetic resonance (MR), ultrasound, and fluoroscopic images.

For example, ultrasound imaging systems utilize sound waves with frequencies higher than the upper audible limit of human hearing. Further, ultrasound imaging systems are widely used in medicine to perform both diagnostic and therapeutic procedures. In such procedures, sonographers perform scans of a patient using a hand-held probe or transducer that is placed directly on and moved over the patient.

Certain ultrasound systems may be used in combination with medical devices having active (i.e., electrically-powered) transducers in order to track the location of the medical device. The transducer can be any piezoelectric material, such as lead zirconate titanate (PZT) transducer or a capacitive micromachined ultrasonic transducer (CMUT) and is typically mounted on the medical device and has a rectangular surface or a flat face at its front and back. Such a geometry can lead to abrasion and irritation of the skin when the medical device is being inserted and retracted through the skin. Further, such a geometry can lead to increased forces

'i acting on the transducer itself, which can create a risk of detachment resulting in a hazard to the patient since the transducers may be formed of materials containing lead.

Thus, a need exists for a medical device containing a nest for the transducer that can reduce the aforementioned abrasion and insertion forces during the insertion and retraction of the medical device.

SUMMARY

Objects and advantages of the present disclosure will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the present disclosure.

In one particular embodiment, the present disclosure is directed to an ultrasound-enabled invasive medical device. The ultrasound-enabled medical device includes an invasive medical device; and a transducer support structure attached to an upper surface of the invasive medical device at a distal end of the invasive medical device, wherein the transducer support structure comprises a first angled wall defining a first ramp angle, wherein the transducer support structure defines a nest.

In another embodiment, the ultrasound-enabled invasive medical device can also include a second angled wall defining a second ramp angle. Further, the first ramp angle can be larger than the second ramp angle, where the first angled wall is located towards the distal end of the invasive medical device and the second angled wall is located towards a proximal end of the invasive medical device. In addition, the first ramp angle can range from about 2.5 degrees to about 45 degrees and the second ramp angle can range from about 1 degree to about 40 degrees.

In still another embodiment, the ultrasound-enabled invasive medical device can include a second ramp angle that is larger than the first ramp angle, where the first angled wall is located towards the distal end of the invasive medical device and the second angled wall is located towards a proximal end of the invasive medical device. Further, the first ramp angle can range from about 1 degree to about 40 degrees and the second ramp angle can range from about 2.5 degrees to about 45 degrees. Additionally, the invasive medical device can have a curved portion located at the distal end of the invasive medical device. In yet another embodiment, the invasive medical device can include a needle, a catheter, a cannula, a punch, or a stylet.

In an additional embodiment, the ultrasound-enabled invasive medical device can include a fiducial that can be used to position the transducer support structure, where the fiducial can be located on a lower surface of the invasive medical device at a proximal end of the invasive medical device.

In one more embodiment, the ultrasound-enabled invasive medical device can include an ultrasound transducer assembly. Further, the ultrasound transducer assembly can be attached to the transducer support structure via an adhesive. Additionally, a height of the transducer support structure can be at least 80% of a height of the ultrasound transducer assembly when the ultrasound transducer assembly is attached to the transducer support structure via the adhesive.

In still another embodiment, the ultrasound transducer assembly can include a single-element array. Alternatively, the ultrasound transducer assembly can include a multi-element array.

In yet another embodiment, the ultrasound transducer assembly can include a transducer element comprising a capacitive micromachined ultrasonic transducer (CMUT), a piezoelectric ultrasonic transducer, or a combination thereof.

In another embodiment of the present disclosure, a transducer support structure is provided. The transducer support structure includes a first angled wall defining a first ramp angle, where the transducer support structure defines a nest, wherein the nest is configured to receive an ultrasound transducer assembly.

In one particular embodiment, the transducer support structure can include a second angled wall defining a second ramp angle. Further, the first ramp angle can be larger than the second ramp angle. For example, the first ramp angle can range from about 2.5 degrees to about 45 degrees, and the second ramp angle can range from about 1 degree to about 40 degrees.

These and other features, aspects and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

Figure 1 is a schematic representation of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 2A is a top view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 2B is a side view of the distal end of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 2C is a top view of the distal end of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 2D is a sectional view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 2E is a portion of the sectional view shown in FIG. 2D that has been enlarged for magnification purposes in accordance with one embodiment of the present disclosure;

Figure 2F is a sectional view of an ultrasound-enabled invasive medical device in accordance one embodiment of the present disclosure;

Figure 3 is a flow chart of a method in accordance with one embodiment of the present disclosure;

Figure 4 is a sectional view of a needle in accordance with one embodiment of the present disclosure;

Figure 5A is a side view of a needle in accordance with one embodiment of the present disclosure;

Figure 5B is a top view of a needle in accordance with one embodiment of the present disclosure;

Figure 6A is a side view of a needle and a transducer support structure in accordance with one embodiment of the present disclosure;

Figure 6B is a top view of a needle and a transducer support structure in accordance one embodiment of the present disclosure; Figure 7A is a perspective view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 7B is a sectional view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 8A is a perspective view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 8B is a sectional view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure;

Figure 9A is a perspective view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure; and

Figure 9B is a side view of an ultrasound-enabled invasive medical device in accordance with one embodiment of the present disclosure.

DETAILED DESCRIPTION

Reference will now be made in detail to one or more embodiments of the present disclosure, examples of the present disclosure, examples of which are illustrated in the drawings. Each example and embodiment is provided by way of explanation of the present disclosure, and is not meant as a limitation of the present disclosure. For example, features illustrated or described as part of one embodiment may be used with another embodiment to yield still a further embodiment. It is intended that the present disclosure include these and other modifications and variations as coming within the scope and spirit of the present disclosure.

As used herein, the terms "about," “approximately,” or “generally,” when used to modify a value, indicates that the value can be raised or lowered by 5% and remain within the disclosed embodiment. Further, when a plurality of ranges are provided, any combination of a minimum value and a maximum value described in the plurality of ranges are contemplated by the present disclosure. For example, if ranges of “from about 20% to about 80%” and “from about 30% to about 70%” are described, a range of “from about 20% to about 70%” or a range of “from about 30% to about 80%” are also contemplated by the present disclosure.

Generally speaking, the present invention is directed to a transducer support structure including one or more ramps or angled walls, where the transducer support structure is configured to house an electronic part within a nest. A medical device that includes the transducer support structure defining a nest and a medical device that includes the transducer support structure defining a nest housing an electronic part (e.g., a transducer) or transducer assembly are also contemplated by the present disclosure. The ramped transducer support structure defining a nest can be built via an epoxy after the transducer assembly is placed on the medical device or it can be printed via 3D printing and cured to form the ramped transducer support structure before the transducer assembly is placed on the medical article. In any event, the ramped transducer support structure and nest allow for ease of insertion and retraction of a medical article that includes a transducer assembly for tracking purposes, enabling the medical article to be visualized via ultrasound based on the location of the transducer while at the same time minimizing skin and tissue abrasion and more evenly distributing the forces acting on the transducer assembly itself. The medical device may be an invasive medical device such as a needle, catheter, cannula, punch, stylet, etc., such as an ultrasound-enabled invasive medical device.

Referring now to the drawings, Figure 1 is a schematic representation of an ultrasound-enabled invasive medical device 10 in accordance with one embodiment of the present disclosure. The ultrasound-enabled invasive medical device 10 includes an invasive medical device 11 , a first electrical trace 13, a second electrical trace 15, a transducer support structure 17, and an ultrasound transducer assembly 19. The ultrasound-enabled invasive medical device 10 is schematically represented as a cylinder in Figure 1 . The ultrasound-enabled invasive medical device 10 may be any type of medical device intended to be used inside a patient’s body. For example, the ultrasound-enabled invasive medical device 10 may be a needle, catheter, cannula, punch, stylet, electrode, stent, or any other medical device that is adapted to be used inside a patient. The ultrasound-enabled invasive medical device 10 may also include a connector adapted to attach the ultrasound-enabled invasive medical device 10 to a processor or medical device located outside of the patient during the procedure. The ultrasound-enabled invasive medical device 10 shown in Figure 1 does not illustrate the connector.

The first electrical trace 13 and the second electrical trace 15 are made of an electrically conductive material that is deposited on either a surface of the invasive medical device 11 or on an insulting layer covering at least a portion of the surface of the invasive medical device 11 . The first electrical trace 13 and the second electrical trace 15 can be deposited by an additive manufacturing process. The electrically conductive material used to form the first electrical trace 13 and the second electrical trace 15 may be any electrically conductive material configured to be deposited, for example, via an additive manufacturing process. For instance, the first electrical trace 13 and the second electrical trace 15 may be made of metals, such as silver, aluminum, copper, gold and/or alloys including silver, aluminum, copper or gold. Additionally, the first electrical trace 13 and the second electrical trace 15 may be made of composite materials, such as a plastic doped with conductive particles. In one embodiment, the first electrical trace 13 and the second electrical trace 15 may be made from single crystal nanoparticles. The single crystal nanoparticles may be any conductive material, such as silver or copper. Additional details about the manufacturing process will be described in more detail below.

The ultrasound transducer assembly 19 includes at least one ultrasound transducer element and may be either a single-element array including only a single ultrasound transducer element, or the ultrasound transducer assembly 19 may be a multi-element array including two or more ultrasound transducer elements. Each of the ultrasound transducer elements may be a piezoelectric (PZT) element, a capacitive micromachined ultrasonic transducer (CMUT) element, or a micromachined ultrasound transducer (MUT) element. It should also be understood that the ultrasound transducer elements in the ultrasound transducer array may be a combination of PZT, CMUT and/or MUT elements. Only two electrical traces are illustrated in the embodiment shown in Figure 1 , but some embodiments may have only a single electrical trace while still other embodiments may have more than two electrical traces. It is necessary to have two electrical connections to each ultrasound transducer element that is configured to be individually controlled. Each individually controllable ultrasound transducer element needs one conductive path to carry a control signal and a second conductive path for a ground return. Embodiments, such as the one shown in Figure 1 , may use two separate electrical traces: one to carry the control signal and another to function as the ground return. In other embodiments, such as those where the invasive medical device is conductive, it is possible to electrically isolate the electrical trace from the invasive medical device and use the invasive device to either carry the control signal or perform as the ground return. An exemplary embodiment using the invasive medical device as a conductive path will be described in detail hereinafter with respect to Figures 8A and 8B. Likewise, in other embodiments still, it is possible to electrically isolate both electrical traces to leave the conductive invasive medical device neutral.

The transducer support structure 17 is shaped to define a nest 60, and the nest is adapted to receive the ultrasound transducer assembly 19. The nest 60 is not easy to see in Figure 1 because the ultrasound transducer assembly 19 is positioned in the nest 60 defined by the transducer support structure 17, but the four-sided nest 60 can be seen more clearly in other figures described in more detail below. The first electrical trace 13 and the second electrical trace 15 are both connected to the ultrasound transducer assembly 19. The first electrical trace 13 may be configured to carry the control signal while the second electrical trace 15 may be adapted to function as the ground return. Alternatively, the first electrical trace 13 may be adapted to function as the ground return while the second electrical trace 15 is configured to carry the control signal.

Figure 2A is a top view of an ultrasound-enabled invasive medical device 12 where the invasive medical device is a needle 22. The ultrasound-enabled invasive medical device 12 includes a first electrical trace 14, a second electrical trace 16, a transducer support structure 18, and an ultrasound transducer assembly 20. The ultrasound-enabled invasive medical device 12 includes a proximal end 21 and a distal end 23. The ultrasound-enabled invasive medical device 12 also includes a first electrical pad 25 and a second electrical pad 27. The first electrical pad 25 and the second electrical pad 27 are configured to electrically connect the ultrasound- enabled medical device 12 to an external device that is configured to provide a control signal to drive the ultrasound transducer assembly 20.

Figure 2B is a side view of the distal end 23 of the ultrasound-enabled invasive medical device 12 and Figure 2C is a top view of the distal end 23 of the ultrasound-enabled invasive medical device 12 in accordance with an exemplary embodiment.

Figure 2D is a sectional view of the ultrasound-enabled invasive medical device 12 along the dashed line A-A’ shown in Figure 2B. Figure 2E is a portion of the sectional view shown in Figure 2D that has been enlarged for magnification purposes. Figure 2E shows an adhesive 24 used to attach the ultrasound transducer assembly 20 inside the nest 60 defined by the transducer support structure 18 and the needle 22, where it is to be understood that the nest 60 includes four sides and an open bottom adjacent an outer surface of the needle 22 (such as, but not limited to, flat surface 71 in Figure 5A) that form a pocket for holding the transducer support structure 18. Figure 2E also shows a first insulating layer 26 and a second insulating layer 28, where the first insulating layer 26 and the needle 22 are in contact with the transducer support structure 18. The first insulating layer 26 and the second insulating layer 28 will be described in more detail hereinafter. Figure 2F is a sectional view along line B-B’.

Figure 3 is a flow chart showing a method 100 in accordance with an exemplary embodiment. The individual blocks of the flow chart represent steps that may be performed in accordance with the method 100. Additional embodiments may perform the steps shown in a different sequence and/or additional embodiments may include additional steps not shown in Figure 3. The technical effect of the method 100 is the manufacturing of an ultrasound-enabled invasive medical device. The method 100 will be described in detail with respect to the manufacture of the ultrasound-enabled invasive medical device 12, previously described with respect to Figures 2A-2F. It should be appreciated by those skilled in the art that the method 100 may be used in the manufacture of ultrasound- enabled invasive medical devices other than the ultrasound-enabled invasive medical device 12 in accordance with various embodiments.

At step 102, an insulating layer is deposited on the invasive medical device, such as the needle 22 according to an exemplary embodiment. The insulating layer may be any insulating material according to various embodiments. According to exemplary embodiments, the insulating layer may be a vapor-deposited poly polymer such as Parylene C or polydimethylsiloxane (PDMS).

Figure 4 is a sectional view of the needle 22 along dashed line A-A’ (shown in Figure 2B) after it has been coated with an insulating layer 26 at step 102. The insulating layer 26 may be deposited though a vacuum-based process, a chemical vapor deposition process, a spin coating process, a mechanical dipping process, or insulating layer 26 may be applied through an additive manufacturing process such as ink-jetting, aerosol jet printing or dispensing. According to an exemplary embodiment, the insulating layer 26 may be deposited on all or a portion of the surface of the needle 22 through a vapor deposition process.

The insulating layer 26 may be deposited on all of the invasive medical device, such as the needle 22, or the insulating layer 26 may be deposited on just a portion of the invasive medical device. For embodiments where it is desirable to deposit the insulating layer on just a portion of the invasive medical device, a mask may be used in order to keep some of the invasive medical device uninsulated.

At step 104, one or more electrical traces are deposited on either the surface of the invasive medical device or on the insulating layer 26 deposited on the surface of the invasive medical device. According to embodiments where the invasive medical device 11 is an electrical insulator, or at least the portion of the invasive medical device 11 where the electrical traces will be deposited is an electrical insulator, it may not be necessary to add an insulating layer. For embodiments where the invasive medical device is not electrically conductive, one or more electrical traces may be deposited directly on the surface of the invasive medical device 11 . Therefore, step 102 may be skipped according to some embodiments.

Figure 5A is a side view of the needle 22 and Figure 5B is a top view of the needle 22 in accordance with an embodiment. Both Figure 5A and Figure 5B show the needle 22 without either the ultrasound transducer assembly 20 or the transducer support structure 18 in order to more clearly show the first electrical trace 14 and the second electrical trace 16. Figures 5A and 5B represent the needle 22 after the electrical traces have been deposited during step 104.

According to the exemplary embodiment shown in, for example, Figures 2A- 2F, the insulating layer 26 is deposited on the surface of the needle 22, and the first electrical trace 14 and the second electrical trace 16 may be deposited on the insulating layer 26 (see Figure 2E). The first electrical trace 14 and the second electrical trace 16 are deposited through an additive manufacturing process, such as ink-jetting, a spin coating process, aerosol jet printing, or dispensing. The first electrical trace 14 and the second electrical trace 16 are both visible in Figure 5B. The first electrical trace 14 includes a first contact portion 50 and a second contact portion 52. The first contact portion 50 is configured to be the point of electrical connection between the ultrasound transducer assembly 20 and the first electrical trace 14; and the second contact portion 52 is configured to be the point of electrical connection between the ultrasound transducer assembly 20 and the second electrical trace 16. Other embodiments may use contact portions that are shaped differently than the first contact portion 50 or the second contact portion 52. One or both of the first electrical trace 14 and the second electrical trace 16 may be shaped to form one or more fiducials. The embodiment shown in Figures 5A and 5B includes a first fiducial 51 , and optionally a second fiducial 54, a third fiducial 56, and a fourth fiducial 58. Each fiducial (51 , 54, 56, 58) or the combination of fiducials (51 , 54, 56, 58) is shaped to be identified quickly and reliably by an optical camera system connected to a processor with a pattern recognition system. While the third fiducial 56 and the fourth fiducial 58 are integral portions of the first electrical trace 14 and the second electrical trace respectively, the first fiducial 51 and second fiducial 54 are separate from either of the electrical traces. The first fiducial 51 is located at a proximal end 21 of the needle 22 and is disposed on a lower surface 32 of the needle 22, while the other fiducials (54, 56, and 58) may be located on an opposing upper surface 34 of the needle 22 at various locations along the length of the needle 22. In particular, the location of the first fiducial 51 aids in properly orienting the invasive medical device (e.g., needle 22) to ensure the proper positioning of the invasive medical device with respect to the mounting plane when positioning an ultrasound transducer assembly 20 into the nest 60 of the transducer support structure 18. For example, due to the location of the first fiducial 51 on the lower surface 32 of the needle 22 and the geometry of the first fiducial 51 , a flat surface is created on the lower surface 32 of the needle 22 to hold the needle 22, which has a circular cross section, in proper positioning during placement of the ultrasound transducer assembly 20. Other embodiments may generate one or more fiducials from materials other than the conductive material used to form the electrical traces.

At step 106, a fiducial (51 , 54, 56, 58) is identified with a processor and an optical camera system. The processor and optical camera system use the fiducial to make sure the transducer support structure 18 is properly positioned with respect to the first electrical trace 14 and the second electrical trace 16 during step 108.

At step 108 the transducer support structure 18 is attached to the ultrasound- enabled invasive medical device 12. As discussed previously, the transducer support structure 18 may be attached to an insulating layer, such as the first insulating layer 26, added to the ultrasound-enabled invasive medical device 12 during step 102 or the transducer support structure 18 may be directly attached to the surface of the invasive device 12. According to an exemplary embodiment, the transducer support structure 18 may be attached to the first insulating layer 26 covering at least a portion of the needle 22.

According to an embodiment, the transducer support structure 18 may be manufactured separately, through a process such as molding or micro-molding, and then laminated to either the ultrasound-enabled invasive medical device 12 or to the first insulating layer 26 covering at least a part of the ultrasound-enabled invasive medical device 12. Figure 6A is a side view of the needle 22 after the transducer support structure 18 has been attached to the needle 22. Figure 6B is a top view of the needle 22 after the transducer support structure 18 has been attached to the needle 22. Figure 6B clearly shows the nest 60 defined by the transducer support structure 18, where a first angled wall 68 and a second angled wall 70 define a ramped configuration for the transducer support structure 18. According to an embodiment, the nest 60 may have dimensions that are between about 100% and about 350%, such as from about 100% to about 325%, such as from about 100% to about 300% of the respective dimensions of the ultrasound transducer assembly attached to the nest 60.

For example, according to an exemplary embodiment where the ultrasound transducer assembly 20 has a width of about 200 micrometers (pm) and a length of about 1000 pm, an inner width 61 of the nest 60 may be about 350 pm and an inner length 62 of the nest 60 may be about 1000 pm. An overall width 63 of the nest 60 may be about 690 pm and an overall length 64 of the nest 60 may be about 3100 pm. In another exemplary embodiment where the ultrasound transducer has a width of about 600 pm and length of about 1000 pm, an inner width 61 of the nest may be about 750 micrometers and an inner length of the nest 60 may be about 1000 pm. An overall width of the nest 60 may be about 990 pm and an overall length 64 of the nest may be about 3100 pm. Further, in one embodiment, the ultrasound transducer assembly 20 includes a first ramp angle 67 ranging from about 2.5 degrees to about 45 degrees, such as from about 5 degrees to about 40 degrees, such as from about 7.5 degrees to about 30 degrees, and a second ramp angle 69 ranging from about 1 degree to about 40 degrees, such as from about 1 .5 degrees to about 30 degrees, such as from about 2 degrees to about 20 degrees. For instance, the first ramp angle 67 formed by the first angled wall 68 can be about 10 degrees and the second ramp angle 69 formed by the second angled wall 70 can be about 6 degrees. The first ramp angle 67 defined by a first angled wall 68 at a more distal end 23 of the needle 22 and the second ramp angle 69 defined by a second angled wall 70 at a more proximal end 21 of the needle 22 are designed to allow for a smoother insertion (and retraction) of the ultrasound-enabled invasive medical device 12 into the patient. The first ramp angle 67 and the second ramp angle 69 help to streamline the ultrasound transducer assembly 20 so that it does not unintentionally abrade or damage additional tissue during the insertion or removal of the ultrasound-enabled invasive medical device 12 and also help to more evenly distribute the forces transferred to the ultrasound transducer assembly 20 itself.

As shown in Figure 2B, the first ramp angle 67 that is located towards the distal end 23 of the needle 22 is steeper or larger than the second ramp angle 69 that is located towards the proximal end 21 of the needle in the embodiment shown in Figure 6B because it is desirable to have the ultrasound transducer assembly 20 closer to a distal end 23 of the needle. Positioning the ultrasound transducer assembly 20 close to the distal end 23 of the needle is desirable for more accurate localization of the needle 22 during interventional procedures.

Other embodiments may use different a different first ramp angle and/or a different second ramp angle, where the first ramp angle associated with the first angled wall that is distally located along the length of the needle may be smaller or shallower than the second ramp angle that is proximally located along the length of the needle. It should be appreciated that the dimensions described above are for one particular embodiment and that the dimensions of the nest 60 and the transducer support structure 18 may be adjusted based on the dimensions of the ultrasound transducer assembly and/or according to various embodiments. In one example and referring to Figures 9A and 9B, when the invasive medical device is in the form of a T uohy needle 122 having a curved portion 124 at the distal end 23, the ultrasound transducer assembly 128 may be protected by a transducer support structure 126 defining a nest 60 that includes a first ramp angle 130 defined by a first angled wall 131 ranging from about 1 degree to about 40 degrees, such as from about 1 .5 degrees to about 30 degrees, such as from about 2 degrees to about 20 degrees, and a second ramp angle 132 defined by a second angled wall 133 ranging from about 2.5 degree to about 45 degrees, such as from about 5 degrees to about 40 degrees, such as from about 7.5 degrees to about 35 degrees. The first ramp angle 130 defined by the first angled wall 131 at a more distal end 23 of the needle 22 and the second ramp angle 132 defined by a second angled wall 133 at a more proximal end 21 of the needle 22 are designed to allow for a smoother insertion of the ultrasound-enabled invasive medical device 12 into the patient, and because of the curved portion 124 of the Tuohy needle 122, the ultrasound transducer assembly 128 is more protected so that the first ramp angle 130 of the first angled wall 131 is not required to be as steep as in instances with a beveled needle 22 where no curved portion is present. The first ramp angle 130 and the second ramp angle 132 help to streamline the ultrasound transducer assembly 128 in conjunction with the curved portion 124 of the Tuohy needle 122 so that it does not unintentionally abrade or damage additional tissue during the insertion or removal of the ultrasound-enabled invasive medical device 120 and also help to more evenly distribute the forces transferred to the ultrasound transducer assembly 128 itself.

In any event, the nest 60 of any of the aforementioned transducer support structures is adapted to receive the ultrasound transducer assembly, such as ultrasound transducer assemblies 19, 20, 84, 94, and 128 by way of example. The placement and lamination of the transducer support structure 18 may be performed as part of an automated process, such as a pick-and-place process according to embodiments. For example, the invasive medical device, such as the needle 22, may be held in a fixture to ensure the accurate placement of the transducer support structure 18 with respect to the electrical traces (14, 16). Or, an optical camera system in conjunction with a processor may be used to identify one or more fiducials, such as the first fiducial 51 , the second fiducial 54, the third fiducial 56, or the fourth fiducial 58 and guide the placement of the transducer support structure 18 to a predetermined position with respect to the one or more fiducials (51 , 54, 56, 58).

According to another embodiment, the transducer support structure 18 may be deposited onto the invasive medical device 12 or onto the insulating layer 26 covering at least a portion of the invasive medical device 12 through an additive manufacturing process. For example, the transducer support structure 18 may be deposited through a process such as ink-jetting, aerosol jet printing, spin coating, or dispensing. The transducer support structure 18 may be deposited by an additive manufacturing process or manufactured separately and then laminated to the needle 22. As described previously, the transducer support structure 18 shown in Figure 7 may be either directly attached to the needle 22 or it may be attached to the insulating layer 26 covering the surface of the needle 22. Since the ultrasound transducer assembly 20 is not shown in Figure 5A and 5B, it is possible to visualize the first electrical trace 14, the second electrical trace 16, and the fiducials (51 , 54, 56, 58).

The transducer support structure 18 defines the nest 60 that is configured to receive the ultrasound transducer assembly 20. The nest 60 is dimensionally slightly larger than the size of the ultrasound transducer assembly 20. For example, the nest 60 may have a length and a width that are between 50 pm and 500 pm larger than a length and a width of the ultrasound transducer assembly 20. According to an embodiment, a height of the transducer support structure 18 is at least 80% of the height of the ultrasound transducer assembly 20. According to other embodiments, the height of the transducer support structure 18 is at least 60% of the height of the ultrasound transducer assembly 20; according to other embodiments, the height of the transducer support structure 18 is at least 70% of the height of the ultrasound transducer assembly 20; and according to other embodiments, the height of the transducer support structure 18 is at least 100% of the height of the ultrasound transducer assembly 20. The transducer support structure 18 ensures that the ultrasound transducer assembly 20 is accurately positioned with respect to the electrical traces, such as the first electrical trace 14 and the second electrical trace 16.

Additionally, using the transducer support structure 18 results in a more accurate placement and a more reliable attachment of the ultrasound transducer assembly 20 to the needle 22. The transducer support structure 18 helps to control the adhesive, such as glue or epoxy, that is used to encapsulate the ultrasound transducer assembly 20. The transducer support structure contains the adhesive that is used for the encapsulation process. Both of these improvements make it easier to produce the ultrasound-enable invasive medical device using automated techniques.

At step 110, the ultrasound transducer assembly 20 is positioned within the nest 60 defined by the transducer support structure 18 and attached to the invasive medical device, such as needle 22. According to an embodiment, an adhesive, such as epoxy may be placed within the nest 60 prior to attaching the ultrasound transducer assembly 20. The nest 60 defined by the transducer support structure 18 advantageously contains the adhesive, which otherwise might run off a small invasive medical device such as a needle. After adding the adhesive, the ultrasound transducer assembly 20 is positioned within the nest 60 defined by the transducer support structure 18. After the adhesive has cured, the ultrasound transducer assembly 20 is secured to the needle 22. The nest 60 defined by the transducer support structure 18 contains the adhesive before placement of the ultrasound transducer assembly and ensures better control of the encapsulation process — i.e. , the process of securing the ultrasound transducer assembly 20 with the adhesive. As the ultrasound transducer assembly 20 is positioned in the nest 60, the adhesive will be displaced and spread out to the sides of the ultrasound transducer assembly 20. The nest 60, however, contains the adhesive and prevents it from spreading beyond the walls of the transducer support structure 18 defining the nest 60. The adhesive then travels up the sides of the ultrasound transducer assembly 20 adjacent to the walls of the transducer support structure 18.

According to an embodiment, the ultrasound transducer assembly 20 may be attached to the needle 22 automatically via a pick-and-place process. The pick-and- place process may, for instance, entail using a pick-and-place robot to grab various components of the ultrasound-enabled invasive medical device and position the individual components on the invasive medical device to assemble the completed ultrasound-enabled invasive medical device. For instance, the pick-and-place robot may attach the transducer support structure 18 to either the needle 22 or to the insulating layer 26 covering the needle 22. The pick-and-place robot may automatically dispense the adhesive within the nest 60, and the pick-and-place robot may then place the ultrasound transducer assembly 20 within the nest 60 after the adhesive has been applied. In addition to helping with the encapsulation process, the nest 60 defined by the transducer support structure 18 helps ensure an accurate placement of the ultrasound transducer assembly with respect to both the needle 22 and with respect to the electrical traces (14, 16). For example, on the embodiment shown in Figures 6A and 6B, the nest 60 defined by the transducer support structure 18 helps ensure that a first electrical contact zone on the ultrasound transducer assembly 20 contacts the first contact portion 50 and that a second electrical contact zone on the ultrasound transducer assembly 20 contacts the second contact portion 52. By increasing the consistency of both the encapsulation process of the ultrasound transducer assembly 20 and the placement of the ultrasound transducer assembly, the use of the nest 60 defined by the transducer support structure 18 make the production of the ultrasound-enabled invasive medical device much more well-suited to automated production processes, such as an automated pick-and-place process. This helps increase the efficiency of production, which may help to provide both an increase in production throughput and/or a decrease in per-unit cost.

At optional step 112, an additional insulating layer may be deposited over the ultrasound-enabled invasive medical device after the ultrasound transducer assembly 20 has been attached. The insulating layer may be a vapor-deposited poly polymer, such as Parylene C or Polydimethylsiloxane (PDMS) for example. However, the insulating layer may be any other insulating material according to various embodiments. The insulating layer added during step 112 may be used to help the bio-compatibility of the ultrasound-enabled invasive medical device. Some materials used for the insulating layer, such as Parylene C, for example, may act as a moisture barrier as well as a dielectric.

In the embodiment described in Figures 2A-2F and Figures 4, 5A-5B, and 6A-6B, the needle 22 is shaped to define a flat surface 71 (see Figure 5A) at the location where the ultrasound transducer assembly 20 will be attached. The needle 22 may, for instance, be machined to form the flat surface 71 prior to depositing the insulating layer 26 during step 102. Other embodiments may not include the flat surface 71 . For instance, a transducer support structure and the ultrasound transducer assembly may be mounted to an invasive medical device with a crosssection that is not flat. For example, the invasive medical device may have a round cross-section at the location where the transducer support structure and the ultrasound transducer assembly are mounted.

Figure 7 A is a perspective view of an ultrasound-enabled invasive medical device 80 in accordance with an embodiment. The ultrasound-enabled invasive medical device 80 includes a needle 81 , a transducer support structure 82, the ultrasound transducer assembly 84, a first electrical trace 86 and the second electrical trace 88. The needle 81 is shaped to have a round cross-section at the location where the transducer support structure 82 and the ultrasound transducer assembly 84 are mounted. Figure 7B is a sectional view of the ultrasound-enabled invasive medical device 80 along dashed line C-C’. In Figure 7B, it is clearly apparent that the cross-section of the needle 81 is round at the location where the transducer support structure 82and the ultrasound transducer assembly 84 are attached to the needle 81 , where the nest 60 holds the ultrasound transducer assembly 84 within the transducer support structure 82.

The transducer support structure 82 may be manufactured separately in a molding or micro-molding process, or the transducer support structure 82 may be deposited on the needle 81 in an additive manufacturing process, such as such as ink-jetting, aerosol jet printing or dispensing. Other than being curved in order to conform to a needle with a curved cross-section, the transducer support structure 82 otherwise functions identically to the transducer support structure 18 described with respect to previous embodiments. While the embodiment shown in Figures 7A and 7B has two electrical traces, other embodiment may have only a single electrical trace or more than two electrical traces. It should be appreciated by those skilled in that the number of individually controllable ultrasound transducer elements in the ultrasound transducer assembly 84 will dictate the number of electrical traces needed. As described hereinabove, each individually controllable ultrasound transducer element requires a conductive path for control signal and a separate conductive path for a ground return.

Figure 8A is a perspective view of an ultrasound-enabled invasive medical device 90 in accordance with an exemplary embodiment. The ultrasound-enabled invasive medical device 90 includes a needle 91 , an insulating layer 98, a first electrical trace 96, and a transducer support structure 92. The ultrasound transducer assembly 94 is a single-element array according to an embodiment. The first electrical trace 96 may be used to provide one of the control signal and the ground return for the ultrasound transducer assembly 94. The other of the control signal and the ground return is provided by the needle 91 , which is made of a conductive material, such as steel. The insulating layer 98 electrically isolates the first electrical trace 96 from the conductive surface of the needle 91 , thus enabling the needle 91 to function as an electrical pathway for the ultrasound-enabled invasive medical device 90.

Figure 8B is a sectional view of the ultrasound-enabled invasive medical device 80 along the dashed line D-D’. Figure 8B shows a sectional view of the ultrasound-enabled invasive medical device 90. Figure 8B clearly shows how the insulating layer 98 electrically isolates the first electrical trace 96 from the needle 91 . According to other embodiments, additional electrical traces may be deposited on the insulating layer. In other words, embodiments may use the needle as one conductive path while relying on two or more electrical traces for additional conductive paths in order to provide individual electrical connections for embodiments where the ultrasound transducer assembly 94 is a multi-element array with two or more ultrasound transducer elements.

This written description uses examples to disclose the present disclosure, including the best mode, and also to enable any person skilled in the art to practice the present disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the present disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

WHAT IS CLAIMED IS:

1. An ultrasound-enabled invasive medical device comprising: an invasive medical device; and a transducer support structure attached to an upper surface of the invasive medical device at a distal end of the invasive medical device, wherein the transducer support structure comprises a first angled wall defining a first ramp angle, wherein the transducer support structure defines a nest.

2. The ultrasound-enabled invasive medical device of claim 1 , further comprising a second angled wall defining a second ramp angle.

3. The ultrasound-enabled invasive medical device of claim 2, wherein the first ramp angle is larger than the second ramp angle, wherein the first angled wall is located towards the distal end of the invasive medical device and the second angled wall is located towards a proximal end of the invasive medical device.

4. The ultrasound-enabled invasive medical device of claim 3, wherein the first ramp angle ranges from about 2.5 degrees to about 45 degrees and the second ramp angle ranges from about 1 degree to about 40 degrees.

5. The ultrasound-enabled invasive medical device of claim 2, wherein the second ramp angle is larger than the first ramp angle, wherein the first angled wall is located towards the distal end of the invasive medical device and the second angled wall is located towards a proximal end of the invasive medical device.

6. The ultrasound-enabled invasive medical device of claim 5, wherein the first ramp angle ranges from about 1 degree to about 40 degrees and the second ramp angle ranges from about 2.5 degrees to about 45 degrees.

7. The ultrasound-enabled invasive medical device of claim 5, wherein the invasive medical device has a curved portion located at the distal end of the invasive medical device.

8. The ultrasound-enabled invasive medical device of claim 1 , wherein the invasive medical device comprises a needle, a catheter, a cannula, a punch, or a stylet.

9. The ultrasound-enabled invasive medical device of claim 1 , further comprising a fiducial used to position the transducer support structure, wherein the fiducial is located on a lower surface of the invasive medical device at a proximal end of the invasive medical device.

10. The ultrasound-enabled invasive medical device of claim 1 , further comprising an ultrasound transducer assembly.

11. The ultrasound-enabled invasive medical device of claim 10, wherein the ultrasound transducer assembly is attached to the transducer support structure via an adhesive.

12. The ultrasound-enabled invasive medical device of claim 11 , wherein a height of the transducer support structure is at least 80% of a height of the ultrasound transducer assembly when the ultrasound transducer assembly is attached to the transducer support structure via the adhesive.

13. The ultrasound-enabled invasive medical device of claim 10, wherein the ultrasound transducer assembly comprises a single-element array.

14. The ultrasound-enabled invasive medical device of claim 10, wherein the ultrasound transducer assembly comprises a multi-element array.

15. The ultrasound-enabled invasive medical device of claim 10, wherein the ultrasound transducer assembly comprises a transducer element comprising a capacitive micromachined ultrasonic transducer (CMUT), a piezoelectric ultrasonic transducer, or a combination thereof.

16. A transducer support structure comprising a first angled wall defining a first ramp angle, wherein the transducer support structure defines a nest, wherein the nest is configured to receive an ultrasound transducer assembly.

17. The transducer support structure of claim 16, further comprising a second angled wall defining a second ramp angle.

18. The transducer support structure of claim 17, wherein the first ramp angle is larger than the second ramp angle.

19. The transducer support structure of claim 16, wherein the first ramp angle ranges from about 2.5 degrees to about 45 degrees.

20. The transducer support structure of claim 17, wherein the second ramp angle ranges from about 1 degree to about 40 degrees.