WO2025145101A1 - Visualization devices and techniques for implanting medical devices - Google Patents

Abstract

Visualization devices and techniques for implanting medical devices are provided. An introducer needle or tool for implanting a baroreflex activation device may include a body extending between distal and proximal end portions, a bevel at the proximal end portion, and a plurality of locations along the body. The bevel can include a first contrast feature, and the plurality of locations can include a second contrast feature. The plurality of locations may indicate or denote one or more electrodes of a baroreflex activation device. The first and second contrast features can visually differentiate the bevel and the plurality of locations when the introducer needle is inserted into a patient. Actuation of the first and second contrast features can enable visualization of the introducer needle when inserted into a patient. The first and second contrast features can comprise various active or passive visibility enhancing features.

Description

VISUALIZATION DEVICES AND TECHNIQUES FOR IMPLANTING MEDICAL DEVICES

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application No. 63/616,264 filed on December 29, 2023, the disclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure generally pertains to implant tools. More particularly, the present disclosure pertains to introducer needles and carotid sinus leads having a passive or active visibility enhancing component to increase implant tool visibility during an implant procedure.

BACKGROUND

One approach for treating hypertension, heart failure, or other cardiovascular disease states is baroreflex activation therapy (or “BAT”), which comprises stimulation of baroreceptors and/or associated nerves or nerve structures of a patient. Baroreceptors are sensory nerve ends that are profusely distributed within the walls of the major arteries, as well as in the heart, aortic arch, carotid sinus or arteries, and in the low-pressure side of the vasculature such as the pulmonary artery and vena cava. Baroreceptor signals are used to activate a number of body systems which collectively may be referred to as the baroreflex system. Baroreceptors are connected to the brain via the nervous system. Thus, the brain is able to detect changes in blood pressure, which can be related to, or indicative of, cardiac output.

Early approaches to BAT systems and associated implant procedures typically required relatively large incisions on one or both sides of a patient’s neck to create sufficient access to the target vasculature in the area of the carotid sinus. The carotid artery was dissected first, then one or more electrode pads were wrapped around the artery and sutured in place.

Current generation implantable BAT devices and systems offer pulse generator housings and associated therapy electrodes with reduced form factors as compared to early systems. One such system, described in U.S. Patent No. 8,437,867 to Murney et al., includes an implantable pulse generator and associated circuitry contained within a hermetically sealed housing, an elongate flexible electrical lead connectable to the housing, and a monopolar electrode structure coupled with the electrical lead.

Current generation implantable BAT devices and systems also offer improvements to the implant procedure. Smaller electrode structures typically allow smaller incisions on the patient. Tire electrode structure described in the above-mentioned U.S. Patent No. 8,437,867 can be implanted via a minimally invasive approach, as described therein.

A recent improvement to the implant procedure for BAT devices and systems involves percutaneous, minimally invasive methods and related devices, as described in published PCT application WO 2020/037145 to Pignato et al. The percutaneous implant methods and devices described therein represent an improvement over prior approaches. However, opportunities exist for further refinements to the introduction of the guidewire associated with the percutaneous implant.

For example, current implant methods and devices typically use ultrasound to view implant tools (e.g., delivery needles, guidewires, implant leads) inside the patient during an implant procedure. During such an implant procedure, ultrasound transducers can be configured to emit sound waves into the patient’s body that are either reflected to produce a signal (echogenic) or absorbed in the body (anechoic). An ultrasonic image can be produced by looking at the amplitude and time delay of the returned signal.

In Doppler ultrasound, which is an inherent function of all ultrasound systems, the ultrasound transducer monitors shifted frequency ranges produced by the Doppler effect (i.e., the change in frequency of a wave in relation to an observer who is moving relative to the source of the wave). The different frequencies can be recorded and overlaid on the ultrasound to produce a colored signal, which is normally used to denote the velocity of blood flow in the patient. During ultrasound guided procedures, it can be difficult to get a clear visualization of the implant tool because of ultrasound signal degradation and other issues affecting image quality. The present disclosure addresses this concern through description of various passive and active visibility enhancing techniques for implant tools.

SUMMARY Embodiments described or otherwise contemplated herein substantially provide the advantages of improving ease of use, operation, accuracy, and patient safety during implant procedures, among other advantages.

In an embodiment, an introducer needle may include a body extending between a distal end portion and a proximal end portion, a bevel extending to a tip at the proximal end portion, a first contrast feature or external marker applied to the bevel and/or the tip, a plurality of locations along the body, with a second contrast feature or external marker applied to the needle surface at the locations. The introducer needle may be configured to carry a baroreflex activation device within the needle, and the location of one or more electrodes of the baroreflex activation device can be indicated or denoted by the plurality of contrasted or externally marked locations along the body of the introducer needle. The plurality locations comprising the second contrast features or external markers may be separated by spaces within or along the body. The first and second contrast features or external markers can be configured to visually differentiate the bevel and the plurality of locations, respectively, when the introducer needle is inserted into a patient with a baroreflex activation device positioned within the needle.

In an embodiment, an introducer needle system may include an introducer needle, and electrical components including a battery, a switch, an analog frequency control, a piezoelectric transducer, and an optional controller, the electrical components all being couplable to the introducer needle, and an ultrasound unit. Electrical activation of the piezoelectric transducer can create an artificial Doppler effect that is visible on an ultrasound scan.

In an embodiment, a carotid sinus lead may include a body extending between a distal end portion and a proximal end portion, a suture wing couplable to and configured to extend outward from the body near the distal end portion, a first contrast feature or external marker applied to the entirety of the carotid sinus lead or just to a portion of the carotid sinus lead such as the body, and a backer or backing disk couplable to and configured to extend outward from the body near the proximal end portion. The backer or backing disk can be configured for attachment to a patient at an insertion site. The backer or backing disk can comprise a second contrast feature or external marker. The first and second contrast features or external markers can be configured to visually differentiate the body and the backer or backing disk, respectively, w'hen the carotid sinus lead is inserted into a patient. Iii an embodiment, a carotid sinus lead system may include a carotid sinus lead, and electrical components including active piezoelectric components that can be actuated through electrical connection to a pulse generator such as an implantable pulse generator. The implantable pulse generator can include electrical components such as a battery and control circuitry, with the electrical components all being couplable to the carotid sinus lead, and an ultrasound unit. Electrical activation of the piezoelectric transducer can create an artificial Doppler effect that is visible on an ultrasound scan.

The above summary is not intended to describe each illustrated embodiment or every implementation of the subject matter hereof. The figures and the detailed description that follow more particularly exemplify various embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

Subject matter hereof may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying figures, in which:

FIG. 1 is a perspective view of a current generation baroreflex activation therapy system, according to an embodiment of the present disclosure.

FIG. 2 is a schematic view of a first design of an introducer needle with contrast features or external markers, according to an embodiment of the present disclosure.

FIG. 3 is a schematic view of a second design of an introducer needle with contrast features or external markers, according to an embodiment of the present discl osure.

FIG. 4 is a schematic view of a third design of an introducer needle with contrast features or external markers, according to an embodiment of the present disclosure.

FIG. 5 is a schematic view of a fourth design of an introducer needle with contrast features or external markers, according to an embodiment of the present disclosure.

FIG. 6 is a schematic view of a first design of a carotid sinus lead with a contrast feature or external marker, according to an embodiment of the present disclosure.

FIG. 7 is a schematic view of a second design of a carotid sinus lead with contrast features or external markers, according to an embodiment of the present disclosure.

FIG. 8A is a top view of a non-contrasted introducer needle, according to an embodiment of the present disclosure.

FIG. 8B is a top view of an introducer needle with larger contrast features or external markers, according to an embodiment of the present disclosure.

FIG. 8C is a top view of an introducer needle with smaller contrast features or external markers, according to an embodiment of the present disclosure.

FIG. 8D is a top view of an introducer needle with larger contrast features or external markers, and a contrasted or externally marked bevel face, according to an embodiment of the present disclosure.

FIG. 9A is a top view of a non-contrasted carotid sinus lead, according to an embodiment of the present disclosure.

FIG. 9B depicts top views of a carotid sinus lead contrasted according to the first design, according to an embodiment of the present disclosure.

FIG. 9C is a top view of a carotid sinus lead contrasted according to the second design, according to an embodiment of the present disclosure.

FIG. 10 is an ultrasound image of an introducer needle with larger contrast features or external markers, according to an embodiment of the present disclosure clearly showing the contrast features or external markers whereas the needle shaft is faint or non-contrasted.

FIG. 1 1 is an ultrasound image of a non-contrasted carotid sinus lead, according to an embodiment of the present disclosure.

FIG. 12A is a block diagram of an introducer needle system with a contrast feature or external marker, according to an embodiment of the present disclosure.

FIG. 12B is a schematic view of an introducer needle with a contrast feature or external marker, according to an embodiment of the present disclosure.

FIGS. 13A-13C are ultrasound images of an introducer needle with a contrast feature or external marker, according to embodiments of the present disclosure.

FIG. 14 is a flowchart of a method of implanting a baroreflex activation therapy system into a patient proximate a carotid sinus, according to embodiments of the present disclosure.

FIG. 15 is a perspective view of an introducer needle with a multi-electrode baroreflex activation device, according to embodiments of the present disclosure.

While various embodiments are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the claimed inventions to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject mater as defined by the claims.

DETAILED DESCRIPTION OF THE DRAWINGS

The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the disclosure.

For information pertaining to the cardiovascular, circulatory and nervous systems, as well as baroreceptor and baroreflex therapy systems that may be used in whole or in part with embodiments of the present disclosure, reference is made to the following commonly assigned published applications and patents: U.S. Published Patent Application Nos. 2006/0004417 to Rossing et al., 2006/0074453 to Kieval et al. and 2008/0082137 to Kieval et al., U.S. Pat. Nos. 6,522,926 to Kieval et al., 6,850,801 to Kieval et al., 6,985,774 to Kieval et al., 7,480,532 to Kieval et al., 7,499,747 to Kieval et al., 7,835,797 to Rossing et al., 7,840,271 to Kieval et al., 8,086,314 to Kieval, 8,326,430 to Georgakopoulos et al., and 9,345,877 to Pignato et al., and published PCT Application No. WO 2024/108027 to Pignato et al., the disclosures of which are hereby incorporated by reference in their entireties.

Embodiments of the present disclosure generally pertain to improved devices and methods for implanting a baroreflex activation therapy system. In embodiments, at least some of the components of the baroreflex activation therapy system can be as described in U.S. Patent No. 8,437,867 to Murney et al., the disclosure of which is incorporated by reference herein. A description of percutaneous, minimally invasive methods and related devices is included in published PCT application WO 2020/037145 (“the ’ 145 PCT publication”) to Pignato et al., the disclosure of which is hereby incorporated by reference.

The present disclosure describes several visibility enhancing features or components applied to implant tools. The visibility enhancing features or components can be passive, active, or a combination of passive and active. Generally, a passive visibility enhancing feature does not require external energy to function. It typically involves using materials or design elements that improve the visibility of the implant tool under certain imaging modalities. For example, a coating applied to an implant that enhances its contrast under ultrasound or X-ray imaging can be characterized as a passive feature. This could be achieved using materials with high radiopacity for X-ray visibility or specific textures or coatings that improve ultrasound reflectivity. Mechanical features such as bead blasted, roughened, or banded surfaces can also be used as passive visibility enhancing features. As such, passive visibility enhancing features rely on physical or chemical properties to enhance implant tool visibility without additional input or activation from another device or system.

In contrast, an active visibility enhancing feature generally requires external energy or activation to function (e.g., actuation by a signal generator with a frequency to enable visualization of the feature when the implant tool is inserted into a patient). Such features typically involve components that emit signals or interact dynamically with an imaging system to enhance visibility. For example, incorporating a piezoelectric transducer (PZT) element or an ultrasonic crystal with the implant can be characterized as an active visibility enhancing feature. These components can generate ultrasound waves when electrically stimulated, which can then be detected by ultrasound imaging systems to make the implant tool visible on an ultrasound scan. Active features can be combined with passive features in certain embodiments of the present disclosure to provide an implant tool with a combined active-passive visibility enhancing feature (e g., an introducer needle implant tool comprising one or more coatings arranged along a needle body and a PZT or ultrasonic element positioned at a needle tip).

Referring now to FIG. 1 , an embodiment of a current generation baroreflex activation therapy system 90 is depicted, including a control system 60, a baroreflex activation device 70, and a lead 72. In embodiments, control system 60 may alternately be referred to as an implantable medical device, an implantable pulse generator, or the like. Control system 60 is understood to include the necessary circuitry and associated components for generating and delivering electrical therapy signals, and other functions. Control system 60 is configured to be implanted within a patient and includes a hermetically sealed housing 68, a header 69 adapted to facilitate connection of one or more leads 72, as well as a case electrode 67 on at least a portion of the outer surface of housing 68. Electrode 67 may also be referred to as an indifferent electrode, common electrode, or reference electrode. As used herein, the words “housing,” “enclosure,” “case,” and “can” are synonymous when used to refer to housing 68.

Control system 60 is configured to generate a control signal (also referred to as a therapy signal), which activates, deactivates or otherwise modulates the baroreflex activation device 70. In an embodiment, the therapy signal is in the range of about 1 to 10 volts, at a rate between 5 Hz and 200 Hz, with an amplitude between 1 and 50 milliamps. Typically, activation of the device 70 via the control signal results in activation of baroreceptors of a patient. Alternatively, deactivation or modulation of the baroreflex activation device 70 may cause or modify activation of the baroreceptors. The baroreflex activation device 70 may include a wide variety of devices which utilize electrical means, such as electrodes, to activate baroreceptors.

The control system memory may contain data related to the therapy signal, a sensor signal, and/or values and commands provided by an input device, such as an external programmer operated by a patient or a clinician. The memory may also include software containing one or more algorithms defining one or more functions or relationships between the therapy signal and the sensor signal. The algorithm may dictate activation or deactivation therapy signals depending on the sensor signal or a mathematical derivative thereof. The algorithm may dictate an activation or deactivation therapy signal when the sensor signal falls below a lower predetermined threshold value, rises above an upper predetermined threshold value, or when the sensor signal indicates a specific physiologic event. The memory may also include software containing one or more algorithms for determining patient physiological parameters based on a measured parameter.

In embodiments, baroreflex activation device 70 may comprise an electrode structure 78 which generally includes an electrode 112 mounted on, integrated with, or otherwise coupled to a backer 114. In an embodiment, electrode structure 78 may be considered to be part of lead 72. Electrode 112 may comprise platinum iridium, and may include a surface treatment, such as iridium oxide or titanium nitride and/or can include steroid, antiinflammatory, antibiotic and/or analgesic compounds, for example. In an example embodiment, electrode 112 may have a diameter of about one millimeter, and backer 114 may have a diameter of about six millimeters. In an embodiment, electrode 112 comprises a cathode, while reference electrode 67 or housing 68 of control system 60 may comprise an anode.

As described in the ’ 145 PCT publication referenced previously, an implant system for implanting an electrode structure and lead in a minimally invasive procedure may include a guidewire delivery tool used with an introducer needle. The guidewire may be pre-curved such that when the guidewire is advanced out of the needle and inserted in a neck of the patient, the tip of the guidewire will advance toward the underside of the skin of the patient and then pushed through the skin, creating a pathway for subsequent lead delivery and electrode fixation. However, during some procedures, proper introduction and placement of the guidewire using the techniques described in the ’ 145 PCT publication can prove difficult. Additionally, ultrasound visualization of the guidewire post-implantation can prove difficult due to poor signal quality and/or signal degradation as the guidewire is advanced through the patient.

Referring to FIG. 2, an introducer needle 200 may include a body 202 extending between a distal end portion 204 and a proximal end portion 206, a bevel 208 extending to a tip 212 at the proximal end portion 206, a first contrast feature or external marker 214 applied to the bevel 208 and/or the tip 212, and a second contrast feature or external marker 220 applied to a plurality of locations along the body 202, the plurality of locations being separated by spaces 218. Each second contrast feature or external marker 220 can indicate the location of an electrode on a lead within the introducer needle 200. For example, the plurality of locations along the body 202 comprising second contrast feature or external marker 220 can indicate the location of a plurality of electrodes of a lead, for example a lead included with a baroreflex activation device, positioned w'ithin the introducer needle 200. In embodiments, introducer needle 200 can be a 14-gauge or 18-gauge needle or other sizes, depending on the requirements of the specific implant procedure. By using a pattern of contrast features or external markers, introducer needle 200 can be configured to better visualize where one or more of the plurality of electrodes of a lead of a baroreflex activation device are located in a patient when the introducer needle 200 is implanted and placed under ultrasound or another visualization mechanism.

Body 202 generally has a hollow' geometry with an opening at the proximal end portion 206 formed by bevel 208. Tip 212, which is located at the proximal end portion 206 of body 202, can be sharpened for easier insertion into a patient during an implant procedure. An electrode or a plurality of electrodes of a baroreflex activation device may be sized and aligned inside of body 202. In an embodiment, the plurality of locations marked with second contrast feature or external marker 220 may have a diameter of approximately one millimeter to match the approximate diameter of the electrode(s), though other suitable diameters and geometries less than or greater than one millimeter are contemplated by this disclosure.

First and second contrast features or external markers 214, 220 may be configured to reflect an ultrasound or other visualization signal which enables the contrasted portions of introducer needle 200 to be visible on an ultrasound or other visualization scan. First and second contrast features or external markers 214, 220 may be applied to introducer needle 200 using a manual or automatic contrasting process. In embodiments, first and second contrast features or external markers 214, 220 may comprise the same material or may comprise different materials.

In embodiments, each one of the plurality of contrasted locations 220 along body 202, specifically each location with second contrast feature or external marker 220, can have a length of approximately five millimeters and can be separated from each other by a space 218 of approximately five millimeters. Other length dimensions for the plurality of contrasted locations 220 and spaces 218 are contemplated by this disclosure, including lengths less than five millimeters such as approximately 2.5 millimeters, and lengths greater than five millimeters such as approximately 7.5 millimeters. Hie particular lengths of the plurality of contrasted locations 220 and spaces 218 will vary depending on the requirements of the implant procedure. In embodiments, each one of the plurality of contrasted locations 220 and each one of the spaces 218 may have the same length dimension or may have different length dimensions. For example, a first contrasted location 220 may have a length of 2.5 millimeters and be separated from a second contrasted location 220 by a length of five millimeters, the second contrasted location 220 having a length of five millimeters. The second contrasted location 220 may be separated from a third contrasted location 220 by a length of 2.5 millimeters, the third contrasted location 220 having a length of 2.5 millimeters. Other length combinations for the plurality of contrasted locations 220 and spaces 218 are contemplated by this disclosure.

In embodiments, each one of the plurality of locations along body 202 may include a second contrast feature or external marker 220 applied thereon. In embodiments, such as introducer needles 300 and 500, one or more of the plurality of locations along body 202 (302, 502) may include no second contrast feature or external marker 220 (320, 520) applied thereon (e.g., with introducer needle 200, the outer locations along body 202 comprise second contrast feature or external marker 220 while the middle location has no second contrast feature or external marker 220). In embodiments, bevel 208 may include no first contrast feature or external marker 214 altogether, or only a portion of bevel 208 may include first contrast feature or external marker 214. Iii embodiments, first and second contrast features or external markers 214, 220 may comprise active or passive visibility enhancing features. In embodiments, first and second contrast features or external markers 214, 220 may comprise coatings applied to the bevel 208 or tip 212, and the plurality of locations along body 202 denoting the location of one or more electrodes of a baroreflex activation device, respectively. In embodiments where first and second contrast features or external markers 214, 220 are coatings, the features 214, 220 may be applied to the introducer needle 200 using a manual or automatic dip coating process. In embodiments, first and second contrast features or external markers 214, 220 may comprise echogenic markers configured to reflect an ultrasound signal to make the features or markers 214, 220 visible on an ultrasound scan. In embodiments, first and second contrast features or external markers 214, 220 may comprise bead blasted surfaces or roughened surfaces of the bevel 208 or tip 212, and the plurality locations along body 202, respectively.

In embodiments, first and second contrast features or external markers 214, 220 may be formed from other mechanical alteration techniques suitable to generate a visibility enhancing feature on the introducer needle 200. In embodiments, first contrast feature or external marker 214 applied to the bevel 208 or the tip 212 may comprise a piezoelectric component such as a piezoelectric transducer or an ultrasonic crystal. In embodiments, the bevel 208 may comprise the first contrast feature or external marker 214, the plurality of locations along body 202 may comprise the second contrast feature or external marker 220, and the tip 212 may comprise a third contrast feature or external marker which may be the same as first or second contrast features or external markers 214, 220 or a different contrast feature or external marker according to the present disclosure.

Referring now to FIG. 3, an introducer needle 300 may include a body 302 extending between a distal end portion 304 and a proximal end portion 306, a bevel 308 extending to a tip 312 at the proximal end portion 306, a first contrast feature or external marker 314 applied to the bevel 308 and/or the tip 312, and a second contrast feature or external marker 320 applied to a plurality of locations along the body 302, the plurality of locations being separated by spaces 318. Each second contrast feature or external marker 320 can indicate the location of an electrode on a lead within the introducer needle 300. For example, the plurality of locations along the body 302 comprising second contrast feature or external marker 320 can indicate the location of a plurality of electrodes of a lead, for example a lead included with a baroreflex activation device, positioned within the introducer needle 300. Introducer needle 300 has many similarities to introducer needle 200 and for simplicity the description of common components is not repeated in the following. Like reference numerals and features names may designate like feature names throughout that are corresponding or analogous. Introducer needle 300 may comprise the same contrast features or external markers and the same contrast feature or external marker arrangements as introducer needle 200 in certain embodiments (e.g., one or more of the passive and active visibility enhancing features described and illustrated herein).

Referring now to FIG. 4, an introducer needle 400 may include a body 402 extending between a distal end portion 404 and a proximal end portion 406, a bevel 408 extending to a tip 412 at the proximal end portion 406, a first contrast feature or external marker 414 applied to the bevel 408 and/or the tip 412, and a second contrast feature or external marker 420 applied to a plurality of locations along the body 402, the plurality of locations being separated by spaces 418. Each second contrast feature or external marker 420 can indicate the location of an electrode on a lead within the introducer needle 400. For example, the plurality of locations along the body 402 comprising second contrast feature or external marker 420 can indicate the location of a plurality of electrodes of a lead, for example a lead included with a baroreflex activation device, positioned within the introducer needle 400.

Introducer needle 400 has many similarities to introducer needles 200 and 300 and for simplicity the description of common components is not repeated in the following. Like reference numerals and features names may designate like feature names throughout that are corresponding or analogous. Introducer needle 400 may comprise the same contrast features or external markers and the same contrast feature or external marker arrangements as introducer needles 200, 300 in certain embodiments (e.g., one or more of the passive and active visibility enhancing features described and illustrated herein).

Referring now to FIG. 5, an introducer needle 500 may include a body 502 extending between a distal end portion 504 and a proximal end portion 506, a bevel 508 extending to a tip 512 at the proximal end portion 506, a first contrast feature or external marker 514 applied to the bevel 508 and/or the tip 512, and a second contrast feature or external marker 520 applied to a plurality of locations along the body 502, the plurality of locations being separated by spaces 518. Each second contrast feature or external marker 520 can indicate the location of an electrode on a lead within the introducer needle 500. For example, the plurality of locations along the body 502 comprising second contrast feature or external marker 520 can indicate the location of a plurality of electrodes of a lead, for example a lead included with a baroreflex activation device, positioned within the introducer needle 500.

Introducer needle 500 has many similarities to introducer needles 200, 300, and 400, and for simplicity the description of common components is not repeated in the following. Like reference numerals and features names may designate like feature names throughout that are corresponding or analogous. Introducer needle 500 may comprise the same contrast features or external markers and the same contrast feature or external marker arrangements as introducer needles 200, 300, and 400 in certain embodiments (e.g., one or more of the passive and active visibility enhancing features described and illustrated herein).

Referring now to FIG. 6, a carotid sinus lead (CSL) 600 may include a body 602 extending between a distal end portion 604 and a proximal end portion 606, a suture wing 608 couplable to and configured to extend outward from the body 602 near the distal end portion 604, a first contrast feature or external marker 612 applied to the entirety of CSL 600 or just to a portion of CSL 600 such as body 602, and a backer or backing disk 616 couplable to and configured to extend outward from the body 602 near the proximal end portion 606. CSL 600 is generally constructed from silicone, though other suitable materials such as metals or different polymers are contemplated by this disclosure.

Body 602 generally has a cylindrical geometry though other suitable geometries are contemplated by this disclosure. Suture wing 608 can be configured for securing CSL 600 to the tissue of a patient during an implant procedure. Suture wing 608 generally has a rectangular geometry though other suitable geometries, such as cylindrical, are contemplated by this disclosure. Backer or backing disk 616 generally has a thin cylindrical geometry and can be configured for attachment to the skin of a patient at an insertion site.

First contrast feature or external marker 612 may be configured to reflect an ultrasound signal which enables the contrasted portions of CSL 600 to be visible on an ultrasound scan (i.e., the entirety of CSL 600 may be visible if completely contrasted, or just portions of CSL 600 that are contrasted). In an embodiment, first contrast feature or external marker 612 may have the same thickness as first and second contrast features or external markers 214, 220 for introducer needle 200. First contrast feature or external marker 612 may be applied to CSL 600 using a manual or automatic contrasting process. First contrast feature or external marker 612 may comprise the same contrast features or external markers and the same contrast feature or external marker arrangements as described for first and second contrast features or external markers 214, 220 of introducer needle 200 or other introducer needles described and illustrated herein. Optionally, CSL 600 may undergo a corona treatment prior to application of first contrast feature or external marker 612 to ensure proper adhesion or application.

In embodiments, CSL 600 may further comprise an electrode couplable to the backer or backing disk 616. hi embodiments, first contrast feature or external marker 612 comprises two or more spaced-apart contrast segments between the distal end portion and proximal end portion.

Referring now to FIG. 7, CSL 700 may include a body 702 extending between a distal end portion 704 and a proximal end portion 706, a suture wing 708 couplable to and configured to extend outward from the body 702 near the distal end portion 704, a first contrast feature or external marker 712 applied to a portion of body 702 between the distal and proximal end portions 704, 706, a spacing 714 between the first contrast feature or external marker 712 and a backer or backing disk 716, the backer or backing disk 716 couplable to and configured to extend outward from the body 702 near the proximal end portion 706. The backer or backing disk 716 may include a second contrast feature or external marker 718 applied all around or just to a specific portion such as the center region of the backer or backing disk 716.

CSL 700 has many similarities to CSL 600, and for simplicity the description of common components is not repeated in the following. Like reference numerals and features names may designate like feature names throughout that are corresponding or analogous. CSL 700 may comprise the same contrast features or external markers and the same contrast feature or external marker arrangements as CSL 600 in certain embodiments (e.g., one or more of the passive and active visibility enhancing features described and illustrated herein).

In an embodiment, first contrast feature or external marker 712 may have a length of approximately 50 millimeters along body 702, and first contrast feature or external marker 712 may be separated from backer or backing disk 716 by a spacing 714 of approximately 10 millimeters. Length dimensions greater than or less than 50 millimeters are contemplated by this disclosure for first contrast feature or external marker 712. Likewise, length dimensions greater than or less than 10 millimeters are contemplated by this disclosure for spacing 714. For example, in a different embodiment, first contrast feature or external marker 712 may have a length of approximately 40 millimeters and may be separated from backer or backing disk 716 by a length of approximately eight millimeters. In an embodiment, first contrast feature or external marker 712 may have a continuous length along body 702, or may be separated into different segments such that there are non-contrasted spacings between contrasted segments of body 702 (i.e., discontinuous contrast feature).

Backer or backing disk 716 may be constructed from silicone and have a diameter of approximately seven millimeters. In embodiments, second contrast feature or external marker 718 may be the same material as first contrast feature or external marker 712, or may be a different material. In embodiments, all or a portion of suture wing 708 may be contrasted with first contrast feature or external marker 712 similar to suture wing 608 of CSL 600. The contrast feature or externally marked patterns of first and second contrast features or external markers 712, 718 may be selected based on the particular implant procedure to be performed and the desired ultrasound signal quality to be obtained.

In embodiments, first and second contrast features or external markers 712, 718 may comprise active or passive visibility enhancing features. In embodiments, first and second contrast features or external markers 712, 718 may comprise coatings applied to the body 702 and the backer or backing disk 716, respectively. In embodiments where first and second contrast features or external markers 712, 718 are coatings, the features or markers 712, 718 may be applied to CSL 700 using a manual or automatic dip coating process. In embodiments, first and second contrast features or external markers 712, 718 may comprise echogenic markers configured to reflect an ultrasound signal to make the features or markers 712, 718 visible on an ultrasound scan. In embodiments, first and second contrast features or external markers 712, 718 may comprise bead blasted surfaces or roughened surfaces of the body 702 and the backer or backing disk 716, respectively.

In embodiments, first and second contrast features or external markers 712, 718 may be formed from other mechanical alteration techniques suitable to generate a visibility enhancing feature on the CSL 700. In embodiments, second contrast feature or external marker 718 applied to the backer or backing disk 716 may comprise a piezoelectric component such as a piezoelectric transducer or an ultrasonic crystal. In embodiments, the body 702 may comprise the first contrast feature or external marker 712, the backer or backing disk 716 may comprise the second contrast feature or external marker 718, and the suture wing 708 may comprise a third contrast feature or external marker which may be the same as first or second contrast features or external markers 712, 718, or a different contrast feature or external marker according to the present disclosure. In embodiments, the second contrast feature or external marker 718 can be applied to a central region of the backer or backing disk 716.

Referring now to FIGS. 8A-8D, top views of a non-contrasted introducer needle 800 (FIG. 8A), a contrasted introducer needle 300 with larger contrast features or external markers in the form of second contrast feature or external marker 320 (FIG. 8B), a contrasted introducer needle 500 with smaller contrast features or external markers in the form of second contrast feature or external marker 520 (FIG. 8C), and a contrasted introducer needle 300 with larger contrast features or external markers and a first contrast feature or external marker 314 applied to bevel 308 and tip 312, are depicted. It should be understood that introducer needles 200, 300, 400, and 500 can be used interchangeably with reference to FIGS. 8A-8D. Second contrast features or external markers 320 and 520 may comprise any of the active or passive visibility enhancing features described and illustrated herein, and may comprise the same or different contrast feature(s).

Referring now to FIGS. 9A-9C, top views of a non-contrasted CSL 850 (FIG. 9A), a CSL 600 that is entirely contrasted from distal end portion 604 to backer or backing disk 616 (FIG. 9B), and a CSL 700 that is contrasted only at a portion of body 702 and on backer or backing disk 716 (FIG. 9C), are depicted. It should be understood that a variety of contrast feature or external marker arrangements having different thicknesses and lengths can be used interchangeably with reference to FIGS. 9A-9C. CSLs 600 and 700 may comprise any of the active or passive visibility enhancing features described and illustrated herein, and may comprise the same or different contrast feature(s) (e.g., CSL 600 may comprise first contrast feature or external marker 612, CSL 700 may comprise first and second contrast features or external markers 712, 718).

Referring now to FIG. 10, an ultrasound image for an introducer needle 200/300 contrasted with contrast features or external markers is depicted. It should be understood that other insertion needles or implant tools described and illustrated herein, for example introducer needles 400 and 500, may achieve similar ultrasound results as those depicted in FIG. 10.

To generate the image shown in FIG. 10, ultrasound testing was performed using a linear probe with visibility assessed between 1 and 5 centimeters of depth. The insertion needles were tested in a human cadaver model. The resulting ultrasound images demonstrate that ultrasound visibility is significantly enhanced in the contrasted insertion needles when compared to the non-contrasted needle segments. The contrasted or externally marked portions of the insertion needles are clearly distinguishable under ultrasound. Specifically, FIG. 10 depicts an implanted introducer needle 200/300 with a second contrast feature or external markers 220 highlighting a location of interest along the introducer needle 200/300 (e.g., the location of two electrodes of a lead of a baroreflex activation device arranged along or within a body, bevel, or tip of introducer needle 200/300).

Referring now to FIG. 11, an ultrasound image for a contrasted or externally marked CSL 600/700 is depicted. It should be understood that other CSL embodiments described and illustrated herein may achieve similar ultrasound results as those depicted in FIG. 11 A. As illustrated, the contrasted or externally marked portion of CSL body 600/700 creates a distinctive shadow which denotes the location of the lead. In such embodiments, CSL 600/700 may comprise a first contrast feature or external marker 612/712 and a second contrast feature or external marker 718 highlighting locations along the CSL 600/700 (e.g., locations of a body, a backer or backing disk, or a suture wing of the CSL 600/700). Overall, providing one or more active or passive contrast features or external markers to CSL embodiments of the present disclosure can significantly enhance their ultrasound or other imaging technique visibility.

Referring now to FIGS. 12A and 12B, an introducer needle system 1000 may include an introducer needle 1010, and electrical components including a battery 1032, a switch 1034, an analog frequency control 1036, a piezoelectric transducer (PZT) 1038, and an optional controller 1044 having a button and multiple settings to change the mode of operating the introducer needle system 1000, the electrical components being couplable to the introducer needle 1010, and an ultrasound unit 1050. One or more of the electrical components may be included with an implantable pulse generator configured to actuate or activate the PZT 1038. Electrical activation of the PZT can create an artificial Doppler effect that is visible on an ultrasound or other imaging technique scan 1060 (i.e., Doppler signal). Introducer needle 1010 has many similarities to previous introducer needles described and illustrated herein, and for simplicity the description and annotation of common components is not repeated in the following. Like reference numerals and features names may designate like feature names throughout that are corresponding or analogous. In embodiments, introducer needle 1010 can be replaced with a carotid sinus lead (CSL) (i.e., to form carotid sinus lead system with the same components) to achieve the same effects as those described for introducer needle system 1000.

Unlike certain conventional systems, introducer needle system 1000 may comprise an ultrasonic crystal positioned near the tip of the introducer needle 1010, on a transitional insert probe, or with the delivered product during implantation and subsequent ultrasound testing (i.e., to achieve mechanical isolation from the insertion needle 1010 to prevent resonant vibrations). In an embodiment, introducer needle system 1000 can comprise a PZT 1038 positioned at the tip of the introducer needle 1010 (or on a surface of the CSL) which is then actuated with a particular frequency within the Doppler bandwidth to create an artificial Doppler effect as illustrated particularly in FIGS. 13A-13C.

Accordingly, introducer needle system 1000 may include an active element of tracking the location of the introducer needle tip or other features of interest in real time with high contrast. The use of an active visibility elements contrasts with passive echogenic solutions such as the contrast features or external markers described previously. The amplitude and frequency of actuation of the PZT can be altered to change how the ultrasound signal is depicted on a scan. This suggests that the amplitude and frequency can be altered to better suit different applications, hi an embodiment, the frequency may be approximately 535 kilohertz, though other frequencies greater than or less than this value may be considered suitable. Moreover, introducer needle system 1000 may have several different form factors while still achieving power requirements and the desired ultrasound visibility results (e.g., 5 to 15 millivolts with an approximately 6 microampere current draw to achieve good visibility).

In other embodiments, introducer needle system 1000 may comprise other active visibility enhancing features in addition to the PZT 1038 or ultrasonic crystal arranged at or near the tip of the introducer needle 1010. In other embodiments, introducer needle 1010 may comprise any of the passive visibility enhancing features described and illustrated herein for various embodiments (e.g., coatings, blasted surfaces, roughened surfaces, banded surfaces, other suitable physical or chemical contrasting features, external markers, or techniques).

Referring now' to FIGS. 13A-13C, ultrasound images of the introducer needle 1010 are depicted showing variations in ultrasound measurements based on different test frequencies. An artificial Doppler effect is created based on actuation of a PZT element positioned at the introducer needle tip or on a surface of a CSL, which generates a higher frequency signal than the transmitted frequency and allows for visualization on the Doppler ultrasound. The resulting signal enables localization of the PZT element and therefore the structure of interest with tunable amplitude and frequencies to adjust signal strength and resolution. Improved visibility under ultrasound afforded by the PZT element facilitates accurate navigation, placement, and identification of contrasted structures under ultrasound imaging.

The imagery of FIG. 13A was generated using a resonant frequency of 920 kilohertz, a peak-to-peak voltage of 5 millivolts, and a return frequency of 540 kilohertz. The imagery of FIG. 13B was generated using a resonant frequency of 525 kilohertz, a peak-to-peak voltage of 5 millivolts, and a return frequency of 535 kilohertz. The imagery of FIG. 13C was generated using a resonant frequency of 920 kilohertz, a peak-to-peak voltage of 10 millivolts, and a return frequency of 530 kilohertz. All imagery was generated using a pulse width of 125 micro-seconds. Similar imagery can be generated using frequency, voltage, and pulse width values less than or greater than the values used to generate the imagery of FIGS. 13A-13C.

The ultrasound images depicted in FIGS. 13A-13C illustrate the effects of changing various signal or ultrasound settings such as signal amplitude and signal frequency. The intensity, strength, or resolution of the depicted imagery can be modified by changing the ultrasound settings relative to the PZT element or other active visibility enhancing feature. Generally, the specific settings to generate accurate imagery will vary depending on the type, shape, and size of PZT element used with introducer needle 1010. Unexpectedly, it was determined that image intensity to generate accurate imagery can be changed with minimal variation to the amount of external energy provided to the system. Also unexpectedly, it was determined that the imagery generated using embodiments of the present disclosure was more accurate than expected and could be enhanced with minor changes to signal settings. As such, embodiments of the present disclosure yield more accurate and clear visualization of the implant tool without experiencing signal or image quality issues associated with conventional techniques.

In other embodiments, an implant system for implanting a baroreflex activation device may comprise an introducer tool, a signal generator, and a visualization system. The introducer tool may comprise any of the introducer needles or CSLs described and illustrated herein. For example, the introducer tool may comprise a body extending between a distal end portion and a proximal end portion, and a bevel extending to a tip at the proximal end portion. The body of the introducer tool can comprise a first contrast feature or external marker and the bevel/tip can comprise a second contrast feature or external marker. The first and second contrast features or external markers can comprise any one or more of the active or passive features described herein for visually differentiating the body and the bevel/tip, respectively, when the introducer tool is inserted into a patient.

The signal generator of the implant system embodiment can be configured to actuate the first and second contrast features or external markers according to a programmed operating frequency. This can enable visualization of the contrast features or external markers on an ultrasound or other imaging technique scan when the introducer tool is inserted into a patient. The amplitude and frequency of actuation by the signal generator can be altered to change how the signal, and by extension the first and second contrast features or external markers, is depicted on an imaging scan. The imaging scan can be depicted on any suitable visualization system configured to visualize the first and second contrast features or external markers (e.g., an ultrasound scan monitor). In embodiments, the visualization system can comprise an imaging device couplable to an external display. The external display can be configured to display imagery of the introducer tool generated by the imaging device when the introducer tool is actuated by the signal generator. Accordingly, the implant system embodiment provides enhanced and more precise visibility of implant tools for baroreflex activation systems and devices compared to conventional techniques.

In other embodiments, the implant system can further comprise a lead having at least one electrode, the lead being arranged along or within the introducer tool. More specifically, embodiments of the implant system can further comprise a lead having at least one electrode, the lead being arranged along or within one or both of the body and the bevel/tip. The at introducer tool can comprise any of the active or passive visibility enhancing features, for example any of the contrast features or external markers, described and illustrated herein. In other embodiments, the implant system can further comprise a suture wing arranged along the introducer tool, and more specifically couplable to the body.

Referring now to FIG. 14, a flowchart 1100 depicting an example method of implanting a baroreflex system or device, for example baroreflex system 60 or baroreflex device 70, is depicted. The method may include a preliminary step of providing an introducer tool such as an introducer needle configured according to embodiments described and illustrated herein. The method may include a preliminary step of providing a signal generator configured to actuate the introducer tool according to a preset frequency. The method may include a preliminary step of providing a visualization system configured to visualize the introducer tool when inserted into a patient. The visualization system may comprise an imaging device couplable to an external display configured to display imagery of the introducer tool generated by the imaging device. Imagery can be generated when the introducer tool is inserted into a patient to visualize the precise location of the tool relative to the target site for implantation of a baroreflex activation system or device.

At 1110, the method may include inserting an introducer tool into a patient at an insertion site. Prior to insertion, a local anesthetic may be administered to the patient proximate the insertion site. Also prior to insertion, ultrasound or another visualization technique may be used to locate a carotid sinus of the patient, and the skin of the patient can be marked accordingly to define the insertion site. The insertion site may be located on the neck of the patient with instruction to insert the introducer tool in a downward direction toward the carotid sinus. Inserting the introducer tool may further comprise defining a small incision caudally (inferior) at the insertion site (i.e., the location of the carotid sinus).

At 1120, the method may include positioning the introducer tool such that the bevel/tip is proximate an intended implant location, specifically a location proximate the carotid sinus. The bevel/tip may comprise a location marked by a contrast feature or external marker to indicate or denote the location of an electrode contained within the bevel/tip. In embodiments, the introducer tool may be an introducer needle having first and second contrast features or external markers to indicate or denote the location of one or more electrodes of a lead of a baroreflex activation device positioned along or within the introducer needle.

At 1130, the method may include actuating the introducer tool with the signal generator to visualize the contrast feature or external marker on the external display, thereby visualizing a position of the introducer tool within the patient. Actuation settings such as signal amplitude and signal frequency can be adjusted using the signal generator to change the image resolution or signal strength outputted on the external display.

At 1140, the method may optionally include adjusting the position of the introducer tool relative to the intended implant location based on the visualized contrast feature or external marker. The introducer tool may be adjusted to a different position closer to the intended implant location such as the carotid sinus lead. For example, the bevel/tip at the proximal end portion, which may comprise, contain, or be proximate to an electrode, can be adjusted or moved to a different position relative to the intended implant location that is more advantageous for baroreflex activation therapy. In embodiments, the bevel/tip can receive an electrode of a baroreflex activation device that has been advanced through the introducer tool during the implant procedure. The electrode can be advanced out of the bevel/tip of the introducer tool and positioned at the intended implant location.

At 1150, the method may include removing at least a portion of the introducer tool from the patient after implanting the baroreflex activation system or device. For example, following successful implantation of at least one electrode proximate the intended implant location, the introducer tool or a portion thereof can be removed from the patient. Successful implantation of the at least one electrode can be determined based on visualizing the contrasted or externally marked introducer tool, prior to implanting the electrode at the intended implant location, on an ultrasound or other visualization scan technique. The implanted baroreflex activation system or device can then be used to perfomi therapy on the patient using the at least one electrode and associated instructions included with the system or device.

In embodiments, the method may further include inserting the introducer tool over a guidewire. In embodiments, the method may further include providing instructions recorded on a tangible medium to a user of the implant system. The instructions may include the steps or operations of the method illustrated in flowchart 1100, along with additional steps or operations necessary for baroreflex activation system or device implantation and associated therapy applied to the carotid sinus lead.

Referring now^r to FIG. 15, an introducer needle 1200 used to implant a multi-electrode baroreflex activation device 1250 is depicted according to embodiments of the present disclosure. Introducer needle 1200 may include a body 1202 extending between a distal end portion 1204 and a proximal end portion 1206, a bevel 1208 extending to a tip 1212 at the proximal end portion 1206, a first contrast feature or external marker 1214 applied to the bevel 1208 and/or the tip 1212, and a second contrast feature or external marker 1220 applied to a plurality of locations along the body 1202, the plurality of locations being separated by spaces. Each second contrast feature or external marker 1220 can indicate the location of an electrode 1252 on a lead within the introducer needle 1200. For example, the plurality of locations along the body 1202 comprising second contrast feature or external marker 1220 can indicate the location of a plurality of electrodes 1252 of a lead, for example a lead included with a baroreflex activation device 1250, positioned within the introducer needle 1200. The lead is depicted in Fig. 15 as partially advanced out of the introducer needle, however it will be understood that during use the lead is positioned within the needle such that the electrodes are aligned with the external markers of the needle.

Introducer needle 1200 has many similarities to previous introducer needles and for simplicity the description of common components is not repeated in the following. Like reference numerals and features names may designate like feature names throughout that are corresponding or analogous. Introducer needle 1200 may comprise the same contrast features or external markers and the same contrast feature or external marker arrangements as previous introducer needles in certain embodiments (e.g., one or more of the passive and active visibility enhancing features described and illustrated herein, for example an active feature on the needle tip 1212 and a passive feature on the needle body 1202).

Further description of introducer needles, baroreflex activation devices, and implant techniques compatible with the teachings of the present disclosure can be found in commonly assigned PCT Published Application No. 2024/108027 to Pignato et al., the disclosure of which is incorporated by reference herein in its entirety.

Various embodiments of systems, devices, and methods have been described herein. These embodiments are given only by way of example and are not intended to limit the scope of the claimed inventions. It should be appreciated, moreover, that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the claimed inventions.

Persons of ordinary skill in the relevant arts will recognize that the subject matter hereof may comprise fewer features than illustrated in any individual embodiment described above. The embodiments described herein are not meant to be an exhaustive presentation of the ways in which the various features of the subject matter hereof may be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, the various embodiments can comprise a combination of different individual features selected from different individual embodiments, as understood by persons of ordinary' skill in the art. Moreover, elements described with respect to one embodiment can be implemented in other embodiments even when not described in such embodiments unless otherwise noted.

Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments can also include a combination of the dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are proposed herein unless it is stated that a specific combination is not intended.

Any incorporation by reference of documents above is limited such that no subject matter is incorporated that is contrary to the explicit disclosure herein. Any incorporation by reference of documents above is further limited such that no claims included in the documents are incorporated by reference herein. Any incorporation by reference of documents above is yet further limited such that any definitions provided in the documents are not incorporated by reference herein unless expressly included herein. For purposes of interpreting the claims, it is expressly intended that the provisions of

35 U.S.C. § 112(f) are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim.

Claims

1. An introducer needle for implanting a baroreflex activation device, comprising: a body extending between a distal end portion and a proximal end portion; a bevel at the proximal end portion; and a plurality of locations positioned along the body, wherein the bevel comprises a first contrast feature and the plurality of locations comprise a second contrast feature, the first and second contrast features configured to visually differentiate the bevel and the plurality of locations when the introducer needle is inserted into a patient for implanting the baroreflex activation device proximate a carotid artery.

2. The introducer needle of claim 1, wherein the first and second contrast features are applied to the bevel and the plurality of locations, respectively.

3. The introducer needle of claim 1, wherein the first and second contrast features comprise echogenic markers configured to reflect an ultrasound signal.

4. The introducer needle of claim 1, wherein the first and second contrast features comprise bead blasted surfaces of the bevel and the plurality of locations, respectively.

5. The introducer needle of claim 1, wherein the first and second contrast features comprise banded surfaces of the bevel and the plurality of locations, respectively.

6. The introducer needle of claim 1, wherein the first contrast feature comprises a piezoelectric transducer.

7. The introducer needle of any one of the preceding claims, wherein the first and second contrast features are the same.

8. The introducer needle of any one of claims 1-6, wherein the first and second contrast features are different.

9. The introducer needle of any one of the preceding claims, wherein the plurality of locations are separated by spaces along the body.

10. The introducer needle of any one of the preceding claims, wherein the bevel extends to a needle tip at the proximal end portion.

11. The introducer needle of claim 10, wherein the needle tip comprises a third contrast feature.

12. The introducer needle of any one of the preceding claims, wherein at least one of the plurality of locations does not comprise the second contrast feature.

13. The introducer needle of any one of the preceding claims, wherein the plurality of locations indicate the approximate location of one or more electrodes of the baroreflex activation device when the device is positioned within the introducer needle.

14. A carotid sinus lead, comprising: a body extending between a distal end portion and a proximal end portion; a suture wing coupled to the body; and a backer coupled to the body at the proximal end portion and configured for attachment to a patient at an insertion site, wherein the body comprises a first contrast feature and the backer comprises a second contrast feature, the first and second contrast features configured to visually differentiate the body and the backer when the carotid sinus lead is inserted into a patient for implanting proximate a carotid artery.

15. The carotid sinus lead of claim 14, wherein the backer comprises an electrode.

16. The carotid sinus lead of any one of claims 14-15, wherein the backer is a backing disk having a thin cylindrical geometry.

17. The carotid sinus lead of any one of claims 14-16, wherein the suture wing is configured to secure the carotid sinus lead to a patient.

18. The carotid sinus lead of any one of claims 14-17, wherein the first contrast feature extends from the distal end portion to the proximal end portion.

19. The carotid sinus lead of any one of claims 14-18, wherein the first contrast feature is positioned between the distal end portion and the proximal end portion.

20. The carotid sinus lead of any one of claims 14-19, wherein the first contrast feature comprises two or more spaced-apart contrast segments between the distal end portion and the proximal end portion.

21. The carotid sinus lead of any one of claims 14-20, wherein the second contrast feature is applied to a central region of the backer.

22. The carotid sinus lead of any one of claims 14-21, wherein the first and second contrast are applied to the body and the backer, respectively.

23. The carotid sinus lead of any one of claims 14-21, wherein the first and second contrast features comprise echogenic markers configured to reflect an ultrasound signal.

24. The carotid sinus lead of any one of claims 14-21, 'wherein the first and second contrast features comprise bead blasted surfaces of the body and the backer, respectively.

25. The carotid sinus lead of any one of claims 14-21, wherein the first and second contrast features comprise banded surfaces of the body and the backer, respectively.

26. The carotid sinus lead of any one of claims 14-21, wherein the second contrast feature comprises a piezoelectric transducer.

27. The carotid sinus lead of any one of claims 14-26, wherein the first and second contrast features are the same.

28. The carotid sinus lead of any one of claims 14-26, wherein the first and second contrast features are different.

29. The carotid sinus lead of any one of claims 14-28, wherein the suture wing comprises a third contrast feature.

30. The carotid sinus lead of claim 29, wherein the third contrast feature is the same as the first contrast feature.

31. A system for implanting a baroreflex activation device, comprising: an introducer tool comprising a body extending between a distal end portion and a proximal end portion, the introducer tool further comprising a bevel extending to a tip at the proximal end portion, wherein the body comprises a first contrast feature and the bevel comprises a second contrast feature, the first and second contrast features configured to visually differentiate the body and the bevel when the introducer tool is inserted into a patient; a signal generator for actuating the first and second contrast features to visualize the first and second contrast features when the introducer tool is inserted into a patient; and a visualization system for visualizing the first and second contrast features.

32. The system of claim 31, further comprising a lead arranged within the body of the introducer tool, the lead comprising at least one electrode.

33. The system of any one of claims 31-32, further comprising a suture wing coupled to the body.

34. The system of any one of claims 31-33, wherein the second contrast feature comprises a piezoelectric transducer.

35. The system of any one of claims 31-34, wherein the visualization system comprises an imaging device coupled to an external display, the external display configured to display imagery of the introducer tool generated by the imaging device when the introducer tool is actuated by the signal generator.

36. An implant method, comprising: inserting an introducer tool into a patient at an insertion site, wherein the introducer tool comprises a body extending between a distal end portion and a proximal end portion, the introducer tool further comprising a bevel extending to a tip at the proximal end portion, wherein the introducer tool comprises a first contrast feature positioned between the distal and proximal end portions; positioning the introducer tool such that the bevel extending to the tip is proximate an intended implant location; and actuating the introducer tool with a signal generator to visualize the first contrast feature on an external display, thereby visualizing a position of the introducer tool within the patient.

37. The method of claim 36, further comprising a second contrast feature positioned on the bevel, wherein the first contrast feature is positioned on the body.

38. The method of claim 37, further comprising actuating the second contrast feature with the signal generator to visualize the second contrast feature on the external display.

39. The method of any one of claims 36-38, wherein the first contrast feature comprises a piezoelectric transducer.

40. The method of any one of claims 36-39, further comprising adjusting at least one of signal amplitude, signal frequency, and signal energy using the signal generator to change image intensity on the external display.

41. The method of any one of claims 36-40, wherein the intended implant location is proximate a carotid artery.