Patent Description:
Intravascular ultrasound (IVUS) imaging is widely used in interventional cardiology as a diagnostic tool for assessing a diseased vessel, such as an artery, within the human body to determine the need for treatment, to guide the intervention, and/or to assess its effectiveness. An IVUS device including one or more ultrasound transducers is passed into the vessel and guided to the area to be imaged. The transducers emit ultrasonic energy in order to create an image of the vessel of interest. Ultrasonic waves are partially reflected by discontinuities arising from tissue structures (such as the various layers of the vessel wall), red blood cells, and other features of interest. Echoes from the reflected waves are received by the transducer and passed along to an IVUS imaging system. The imaging system processes the received ultrasound echoes to produce a cross-sectional image of the vessel where the device is placed.

Solid-state (also known as synthetic-aperture) IVUS catheters are one of the two types of IVUS devices commonly used today, the other type being the rotational IVUS catheter. Solid-state IVUS catheters carry a scanner assembly that includes an array of ultrasound transducers distributed around its circumference along with one or more integrated circuit controller chips mounted adjacent to the transducer array. The controllers select individual acoustic elements (or groups of elements) for transmitting an ultrasound pulse and for receiving the ultrasound echo signal. By stepping through a sequence of transmit-receive pairs, the solid-state IVUS system can synthesize the effect of a mechanically scanned ultrasound transducer but without moving parts (hence the solid-state designation). Since there is no rotating mechanical element, the transducer array can be placed in direct contact with the blood and vessel tissue with minimal risk of vessel trauma. Furthermore, because there is no rotating element, the electrical interface is simplified. The solid-state scanner can be wired directly to the imaging system with a simple electrical cable and a standard detachable electrical connector, rather than the complex rotating electrical interface required for a rotational IVUS device.

Manufacturing solid-state IVUS devices sufficiently narrow to traverse anatomic structures within the human vasculature is challenging and two general performance standards must be met. First, IVUS devices must be extremely narrow to successfully pass through the small lumens in the human body without damaging tissue and second, despite their small size, intraluminal imaging devices must have high tensile strength to ensure that the device or parts of the device do not separate during a procedure. Such a breakage may cause parts of an intraluminal imaging device to be left within the heart or vasculature creating a condition that is extremely difficult to remedy. Generally, connections between various components of intraluminal imaging devices exhibit weaker tensile strength than unitary structures and are therefore more prone to separation. In addition, current methods of connecting components of intraluminal imaging devices often result in increased overall diameters of the device limiting the ability of the device to safely and successfully maneuver through constrained spaces. Increased overall diameter at connections may also make the surface of the device less uniform and more disposed to agitate or damage tissues within the body.

<CIT> discloses an intraluminal imaging device comprising a flexible elongate member configured to be inserted into a body lumen of a patient, an ultrasound imaging assembly disposed at the distal portion of the flexible elongate member. The imaging assembly comprises a support member, a flexible substrate positioned around the support member, a plurality of ultrasound transducer elements integrated in the flexible substrate, and a plurality of control circuits disposed on the flexible substrate at a position proximal to the plurality of transducer elements. A distal member is coupled to the distal portion of the support member. The flexible substrate, the support member, the distal member, a proximal inner member, and/or a proximal outer member are coupled to one another via an adhesive.

<CIT> discloses an intraluminal imaging device comprising a flexible elongate member configured to be inserted into a lumen of a patient, an ultrasound imaging assembly disposed at the distal portion of the a flexible elongate member and configured to obtain ultrasound imaging data while positioned within the lumen of the patient, a tip member disposed at the distal portion of the flexible elongate member, the tip member comprising a cavity adjacent to the ultrasound imaging assembly and configured to be filled with an adhesive to couple the tip member and the ultrasound imaging assembly.

Embodiments of the present disclosure are intraluminal imaging devices, such as intravascular ultrasound (IVUS) catheters. The IVUS catheter described herein provides stronger attachment between components at the distal end, which overcome the limitations described above. For example, an ultrasound imaging assembly is coupled to a proximal end of the tip member. The imaging assembly is formed of a polymer support member and a flexible substrate positioned around the support member. The distal end of the support member includes one or more recesses. A proximal end of the tip member includes one or more protrusions extending inwardly into the inner lumen created by the tip member. These proximal protrusions received into the corresponding recesses of the support member. As a result, the proximal protrusions of the tip member directly contact an inner polymer member forming part of the catheter body and extending through the lumen created by the support member. When heated during a reflow process, the proximal protrusions of the polymer tip member fuse with the polymer inner member and form a strong mechanical connection in and around the support member. Adhesive may be used to further bond the tip member to the support member and flexible substrate. In other embodiments, the protrusions and recesses are located in different places, such as different components of the IVUS catheter than those described above. For example, the support member can include projections that are received within recesses of the tip member. Connecting the components of the IVUS catheter as described herein increase the tensile strength of these bonds while also ensuring a smaller overall diameter.

In an exemplary aspect, an intraluminal imaging device is provided. The intraluminal imaging device comprises a flexible elongate member configured to be positioned within a body lumen of a patient, the flexible elongate member comprising a proximal portion and a distal portion; an ultrasound imaging assembly disposed at the distal portion of the flexible elongate member and configured to obtain ultrasound data while positioned within the body lumen; and a tip member coupled to the ultrasound imaging assembly, wherein the tip member comprises a protrusion, wherein the ultrasound imaging assembly comprises a recess, and wherein the protrusion is received within the recess.

In some aspects, the ultrasound imaging assembly comprises a support member and a flexible substrate positioned around the support member, and the support member comprises the recess. In some aspects, the support member comprises a proximal portion and a distal portion, wherein the recess is disposed at the distal portion of the support member, the tip member comprises a proximal portion and a distal portion, the protrusion is disposed at the proximal portion of the tip member, and the distal portion of the support member is coupled to the proximal portion of the tip member. In some aspects, the flexible elongate member comprises an inner member extending through the support member such that the recess exposes a portion of the inner member. In some aspects, the support member comprises a first surface and an opposite, second surface, and the recess extends from the first surface to the second surface. In some aspects, the protrusion is in contact with the exposed portion of the inner member. In some aspects, the protrusion is coupled to the exposed portion of the inner member. In some aspects, the tip member comprises a first polymer and the inner member comprises a second polymer, and the first polymer of the protrusion is fused to the second polymer of the inner member. In some aspects, the protrusion extends radially inward. In some aspects, the support member comprises a plurality of recesses, and the tip member comprises a plurality of protrusions, wherein the plurality of protrusions is received within the plurality of recesses. In some aspects, the tip member comprises an outer surface, the outer surface comprises a first sloped portion and an opposite, second sloped portion, and the protrusion is aligned with the first sloped portion.

In an exemplary aspect, an intraluminal imaging device is provided. The intraluminal imaging device comprises a flexible elongate member configured to be positioned within a body lumen of a patient, the flexible elongate member comprising a proximal portion and a distal portion; an ultrasound imaging assembly disposed at the distal portion of the flexible elongate member and configured to obtain ultrasound data while positioned within the body lumen, wherein the ultrasound imaging assembly comprises: a support member comprising a first stand, a second stand, a third stand, and a ridge; and a flexible substrate positioned around the first stand, the second stand, and the third stand, wherein the flexible substrate comprises a plurality of integrated circuit chips and an ultrasound transducer assembly; a filling material between the first stand, the second stand, and a portion of the flexible substrate comprising the plurality of integrated circuit chips; and an acoustic backing material between the second stand, the third stand, and a portion of the flexible substrate comprising the ultrasound transducer assembly; and a tip member coupled to the ultrasound imaging assembly, wherein the tip member comprises a groove receiving the ridge.

In some aspects, the groove of the tip member is configured to engage the ridge of the support member to allow relative movement between the tip member and support member in a first direction and restrict the relative movement in an opposite, second direction. In some aspects, the groove of the tip member comprises a proximal portion and a distal portion, the proximal portion of the groove has a first diameter larger than a second diameter of the distal portion of the groove, the ridge of the support member comprises a proximal portion and a distal portion, and the proximal portion of the ridge has a third diameter larger than a fourth diameter of the distal portion of the ridge. In some aspects, the support member comprises a plurality of ridges, and the tip member comprises a plurality of grooves receiving the plurality of ridges.

In an exemplary aspect, an intravascular ultrasound (IVUS) imaging catheter is provided. The IVUS imaging catheter comprises a flexible elongate member configured to be positioned within a blood vessel of a patient, the flexible elongate member comprising a proximal portion, a distal portion, an inner polymer member, and an outer polymer member positioned around the inner polymer member; an ultrasound imaging assembly disposed at the distal portion of the flexible elongate member and configured to obtain ultrasound data while positioned within the blood vessel, wherein the ultrasound imaging assembly comprises a support member and a flexible substrate positioned around the support member, wherein the flexible substrate comprises an ultrasound transducer array, wherein the inner polymer member extends through the support member, wherein the support member comprises a plurality of recesses exposing portions of the inner member extending through support member; and a polymer tip member coupled to the ultrasound imaging assembly, wherein the polymer tip member comprises a plurality of protrusions received within the plurality of recesses such that the plurality of protrusions is fused to the exposed portions of the polymer inner member.

For example, while the focusing system is described in terms of cardiovascular imaging, it is understood that it is not intended to be limited to this application. The system is equally well suited to any application requiring imaging within a confined cavity.

<FIG> is a diagrammatic schematic view of an intraluminal imaging system <NUM>. The intraluminal imaging system <NUM> can be an ultrasound imaging system. In some instances, the system <NUM> can be an intravascular ultrasound (IVUS) imaging system. The system <NUM> may include an intraluminal imaging device <NUM> such as a catheter, guide wire, or guide catheter, a patient interface module (PIM) <NUM>, a processing system or console <NUM>, and a monitor <NUM>. The intraluminal imaging device <NUM> can be an ultrasound imaging device. In some instances, the device <NUM> can be an IVUS imaging device, such as a solid-state IVUS device.

At a high level, the IVUS device <NUM> emits ultrasonic energy from a transducer array <NUM> included in scanner assembly <NUM> mounted near a distal end of the catheter device. The ultrasonic energy is reflected by tissue structures in the medium, such as a vessel <NUM>, or another body lumen surrounding the scanner assembly <NUM>, and the ultrasound echo signals are received by the transducer array <NUM>. In that regard, the device <NUM> can be sized, shaped, or otherwise configured to be positioned within the body lumen of a patient. The PIM <NUM> transfers the received echo signals to the console or computer <NUM> where the ultrasound image (including the flow information) is reconstructed and displayed on the monitor <NUM>. The console or computer <NUM> can include a processor and a memory. The computer or computing device <NUM> can be operable to facilitate the features of the IVUS imaging system <NUM> described herein. For example, the processor can execute computer readable instructions stored on the non-transitory tangible computer readable medium.

The PIM <NUM> facilitates communication of signals between the IVUS console <NUM> and the scanner assembly <NUM> included in the IVUS device <NUM>. This communication includes the steps of: (<NUM>) providing commands to integrated circuit controller chip(s) 206A and 206B, illustrated in <FIG>, included in the scanner assembly <NUM> to select the particular transducer array element(s), or acoustic element(s), to be used for transmit and receive, (<NUM>) providing the transmit trigger signals to the integrated circuit controller chip(s) 206A and 206B included in the scanner assembly <NUM> to activate the transmitter circuitry to generate an electrical pulse to excite the selected transducer array element(s), and/or (<NUM>) accepting amplified echo signals received from the selected transducer array element(s) via amplifiers included on the integrated circuit controller chip(s)<NUM> of the scanner assembly <NUM>. In some embodiments, the PIM <NUM> performs preliminary processing of the echo data prior to relaying the data to the console <NUM>. In examples of such embodiments, the PIM <NUM> performs amplification, filtering, and/or aggregating of the data. In an embodiment, the PIM <NUM> also supplies high- and low-voltage DC power to support operation of the device <NUM> including circuitry within the scanner assembly <NUM>.

The IVUS console <NUM> receives the echo data from the scanner assembly <NUM> by way of the PIM <NUM> and processes the data to reconstruct an image of the tissue structures in the medium surrounding the scanner assembly <NUM>. The console <NUM> outputs image data such that an image of the vessel <NUM>, such as a cross-sectional image of the vessel <NUM>, is displayed on the monitor <NUM>. Vessel <NUM> may represent fluid filled or surrounded structures, both natural and man-made. The vessel <NUM> may be within a body of a patient. The vessel <NUM> may be a blood vessel, as an artery or a vein of a patient's vascular system, including cardiac vasculature, peripheral vasculature, neural vasculature, renal vasculature, and/or or any other suitable lumen inside the body. For example, the device <NUM> may be used to examine any number of anatomical locations and tissue types, including without limitation, organs including the liver, heart, kidneys, gall bladder, pancreas, lungs; ducts; intestines; nervous system structures including the brain, dural sac, spinal cord and peripheral nerves; the urinary tract; as well as valves within the blood, chambers or other parts of the heart, and/or other systems of the body. In addition to natural structures, the device <NUM> may be used to examine man-made structures such as, but without limitation, heart valves, stents, shunts, filters and other devices.

In some embodiments, the IVUS device includes some features similar to traditional solid-state IVUS catheters, such as the EagleEye® catheter available from Volcano Corporation and those disclosed in <CIT>. For example, the IVUS device <NUM> includes the scanner assembly <NUM> near a distal end of the device <NUM> and a transmission line bundle <NUM> extending along the longitudinal body of the device <NUM>. The transmission line bundle or cable <NUM> can include a plurality of conductors, including one, two, three, four, five, six, seven, or more conductors <NUM> (<FIG>). It is understood that any suitable gauge wire can be used for the conductors <NUM>. In an embodiment, the cable <NUM> can include a four-conductor transmission line arrangement with, e.g., <NUM> diameter (<NUM> AWG gauge) wires. In an embodiment, the cable <NUM> can include a seven-conductor transmission line arrangement utilizing, e.g., <NUM> diameter (<NUM> AWG gauge) wires. In some embodiments, <NUM> diameter (<NUM> AWG gauge) wires can be used.

The transmission line bundle <NUM> terminates in a PIM connector <NUM> at a proximal end of the device <NUM>. The PIM connector <NUM> electrically couples the transmission line bundle <NUM> to the PIM <NUM> and physically couples the IVUS device <NUM> to the PIM <NUM>. In an embodiment, the IVUS device <NUM> further includes a guide wire exit port <NUM>. Accordingly, in some instances the IVUS device is a rapid-exchange catheter. The guide wire exit port <NUM> allows a guide wire <NUM> to be inserted towards the distal end in order to direct the device <NUM> through the vessel <NUM>.

<FIG> is a diagrammatic top view of a portion of a flexible assembly <NUM>. The flexible assembly <NUM> includes a transducer array <NUM> formed in a transducer region <NUM> and transducer control logic dies <NUM> (including dies 206A and 206B) formed in a control region <NUM>, with a transition region <NUM> disposed therebetween. The transducer array <NUM> includes an array of ultrasound transducers <NUM>. The transducer control logic dies <NUM> are mounted on a flexible substrate <NUM> into which the transducers <NUM> have been previously integrated. The flexible substrate <NUM> is shown in a flat configuration in <FIG>. Though six control logic dies <NUM> are shown in <FIG>, any number of control logic dies <NUM> may be used. For example, one, two, three, four, five, six, seven, eight, nine, ten, or more control logic dies <NUM> may be used.

The flexible substrate <NUM>, on which the transducer control logic dies <NUM> and the transducers <NUM> are mounted, provides structural support and interconnects for electrical coupling. The flexible substrate <NUM> may be constructed to include a film layer of a flexible polyimide material such as KAPTON™ (trademark of DuPont). Other suitable materials include polyester films, polyimide films, polyethylene napthalate films, or polyetherimide films, liquid crystal polymer, other flexible printed semiconductor substrates as well as products such as Upilex® (registered trademark of Ube Industries) and TEFLON® (registered trademark of E. In the flat configuration illustrated in <FIG>, the flexible substrate <NUM> has a generally rectangular shape. As shown and described herein, the flexible substrate <NUM> is configured to be wrapped around a support member <NUM> (<FIG>) in some instances. Therefore, the thickness of the film layer of the flexible substrate <NUM> is generally related to the degree of curvature in the final assembled flexible assembly <NUM>. In some embodiments, the film layer is between <NUM> and <NUM>, with some particular embodiments being between <NUM> and <NUM>, e.g., <NUM>.

The set of transducer control logic dies <NUM> is a non-limiting example of a control circuit. The transducer region <NUM> is disposed at a distal portion <NUM> of the flexible substrate <NUM>. The control region <NUM> is disposed at a proximal portion <NUM> of the flexible substrate <NUM>. The transition region <NUM> is disposed between the control region <NUM> and the transducer region <NUM>. Dimensions of the transducer region <NUM>, the control region <NUM>, and the transition region <NUM> (e.g., lengths <NUM>, <NUM>, <NUM>) can vary in different embodiments. In some embodiments, the lengths <NUM>, <NUM>, <NUM> can be substantially similar or, the length <NUM> of the transition region <NUM> may be less than lengths <NUM> and <NUM>, the length <NUM> of the transition region <NUM> can be greater than lengths <NUM>, <NUM> of the transducer region and controller region, respectively.

The control logic dies <NUM> are not necessarily homogenous. In some embodiments, a single controller is designated a master control logic die 206A and contains the communication interface for cable <NUM>, between a processing system, e.g., processing system <NUM>, and the flexible assembly <NUM>. Accordingly, the master control circuit may include control logic that decodes control signals received over the cable <NUM>, transmits control responses over the cable <NUM>, amplifies echo signals, and/or transmits the echo signals over the cable <NUM>. The remaining controllers are slave controllers 206B. The slave controllers 206B may include control logic that drives a transducer <NUM> to emit an ultrasonic signal and selects a transducer <NUM> to receive an echo. In the depicted embodiment, the master controller 206A does not directly control any transducers <NUM>. In other embodiments, the master controller 206A drives the same number of transducers <NUM> as the slave controllers 206B or drives a reduced set of transducers <NUM> as compared to the slave controllers 206B. In an exemplary embodiment, a single master controller 206A and eight slave controllers 206B are provided with eight transducers assigned to each slave controller 206B.

To electrically interconnect the control logic dies <NUM> and the transducers <NUM>, in an embodiment, the flexible substrate <NUM> includes conductive traces <NUM> formed in the film layer that carry signals between the control logic dies <NUM> and the transducers <NUM>. In particular, the conductive traces <NUM> providing communication between the control logic dies <NUM> and the transducers <NUM> extend along the flexible substrate <NUM> within the transition region <NUM>. In some instances, the conductive traces <NUM> can also facilitate electrical communication between the master controller 206A and the slave controllers 206B. The conductive traces <NUM> can also provide a set of conductive pads that contact the conductors <NUM> of cable <NUM> when the conductors <NUM> of the cable <NUM> are mechanically and electrically coupled to the flexible substrate <NUM>. Suitable materials for the conductive traces <NUM> include copper, gold, aluminum, silver, tantalum, nickel, and tin, and may be deposited on the flexible substrate <NUM> by processes such as sputtering, plating, and etching. In an embodiment, the flexible substrate <NUM> includes a chromium adhesion layer. The width and thickness of the conductive traces <NUM> are selected to provide proper conductivity and resilience when the flexible substrate <NUM> is rolled. In that regard, an exemplary range for the thickness of a conductive trace <NUM> and/or conductive pad is between <NUM>-<NUM>. For example, in an embodiment, <NUM> conductive traces <NUM> are separated by <NUM> of space. The width of a conductive trace <NUM> on the flexible substrate may be further determined by the width of the conductor <NUM> to be coupled to the trace/pad.

The flexible substrate <NUM> can include a conductor interface <NUM> in some embodiments. The conductor interface <NUM> can be in a location of the flexible substrate <NUM> where the conductors <NUM> of the cable <NUM> are coupled to the flexible substrate <NUM>. For example, the bare conductors of the cable <NUM> are electrically coupled to the flexible substrate <NUM> at the conductor interface <NUM>. The conductor interface <NUM> can be tab extending from the main body of flexible substrate <NUM>. In that regard, the main body of the flexible substrate <NUM> can refer collectively to the transducer region <NUM>, controller region <NUM>, and the transition region <NUM>. In the illustrated embodiment, the conductor interface <NUM> extends from the proximal portion <NUM> of the flexible substrate <NUM>. In other embodiments, the conductor interface <NUM> is positioned at other parts of the flexible substrate <NUM>, such as the distal portion <NUM>, or the flexible substrate <NUM> may lack the conductor interface <NUM>. A value of a dimension of the tab or conductor interface <NUM>, such as a width <NUM>, can be less than the value of a dimension of the main body of the flexible substrate <NUM>, such as a width <NUM>. In some embodiments, the substrate forming the conductor interface <NUM> is made of the same material(s) and/or is similarly flexible as the flexible substrate <NUM>. In other embodiments, the conductor interface <NUM> is made of different materials and/or is comparatively more rigid than the flexible substrate <NUM>. For example, the conductor interface <NUM> can be made of a plastic, thermoplastic, polymer, hard polymer, etc., including polyoxymethylene (e.g., DELRIN®), polyether ether ketone (PEEK), nylon, Liquid Crystal Polymer (LCP), and/or other suitable materials.

<FIG> illustrates a perspective view of the scanner assembly <NUM> in a rolled configuration. In some instances, the flexible substrate <NUM> is transitioned from a flat configuration (<FIG>) to a rolled or more cylindrical configuration (<FIG>). For example, in some embodiments, techniques are utilized as disclosed in one or more of <CIT>, titled "ULTRASONIC TRANSDUCER ARRAY AND METHOD OF MANUFACTURING THE SAME" and <CIT>, titled "HIGH RESOLUTION INTRAVASCULAR ULTRASOUND SENSING ASSEMBLY HAVING A FLEXIBLE SUBSTRATE".

In some embodiments, the transducer elements <NUM> and/or the controllers <NUM> can be positioned in an annular configuration, such as a circular configuration or in a polygon configuration, around a longitudinal axis <NUM> of a support member <NUM>. It will be understood that the longitudinal axis <NUM> of the support member <NUM> may also be referred to as the longitudinal axis of the scanner assembly <NUM>, the flexible elongate member <NUM>, and/or the device <NUM>. For example, a cross-sectional profile of the imaging assembly <NUM> at the transducer elements <NUM> and/or the controllers <NUM> can be a circle or a polygon. Any suitable annular polygon shape can be implemented, such as one based on the number of controllers/transducers, flexibility of the controllers/transducers, etc., including a pentagon, hexagon, heptagon, octagon, nonagon, decagon, etc. In some examples, the plurality of transducer controllers <NUM> may be used for controlling the plurality of ultrasound transducer elements <NUM> to obtain imaging data associated with the vessel <NUM>.

The support member <NUM> can be referenced as a unibody in some instances. The support member <NUM> can be composed of a metallic material, such as stainless steel, or a non-metallic material, such as a plastic or polymer as described in <CIT>, ('<NUM> Application). In some embodiments, support member <NUM> may be composed of <NUM> stainless steel. The support member <NUM> can be a ferrule having a distal flange or portion <NUM> and a proximal flange or portion <NUM>. The support member <NUM> can be tubular in shape and define a lumen <NUM> extending longitudinally therethrough. The lumen <NUM> can be sized and shaped to receive the guide wire <NUM>. The support member <NUM> can be manufactured using any suitable process. For example, the support member <NUM> can be machined and/or electrochemically machined or laser milled, such as by removing material from a blank to shape the support member <NUM>, or molded, such as by an injection molding process.

Referring now to <FIG>, shown there is a diagrammatic cross-sectional side view of a distal portion of the intraluminal imaging device <NUM>, including the flexible substrate <NUM> and the support member <NUM>. The support member <NUM> can be referenced as a unibody in some instances. The support member <NUM> can be composed of a metallic material, such as stainless steel, or a non-metallic material, such as a plastic or polymer as described in <CIT>. The support member <NUM> can be ferrule having a distal portion <NUM> and a proximal portion <NUM>. The support member <NUM> can define a lumen <NUM> extending along the longitudinal axis LA. The lumen <NUM> is in communication with the entry/exit port <NUM> and is sized and shaped to receive the guide wire <NUM> (<FIG>). The support member <NUM> can be manufactured according to any suitable process. For example, the support member <NUM> can be machined and/or electrochemically machined or laser milled, such as by removing material from a blank to shape the support member <NUM>, or molded, such as by an injection molding process. In some embodiments, the support member <NUM> may be integrally formed as a unitary structure, while in other embodiments the support member <NUM> may be formed of different components, such as a ferrule and stands <NUM>, <NUM>, that are fixedly coupled to one another. In some cases, the support member <NUM> and/or one or more components thereof may be completely integrated with inner member <NUM>. In some cases, the inner member <NUM> and the support member <NUM> may be joined as one, e.g., in the case of a polymer support member.

Stands <NUM>, <NUM> that extend vertically are provided at the distal and proximal portions <NUM>, <NUM>, respectively, of the support member <NUM>. The stands <NUM>, <NUM> elevate and support the distal and proximal portions of the flexible substrate <NUM>. In that regard, portions of the flexible substrate <NUM>, such as the transducer portion <NUM> (or transducer region <NUM>), can be spaced from a central body portion of the support member <NUM> extending between the stands <NUM>, <NUM>. The stands <NUM>, <NUM> can have the same outer diameter or different outer diameters. For example, the distal stand <NUM> can have a larger or smaller outer diameter than the proximal stand <NUM> and can also have special features for rotational alignment as well as control chip placement and connection. To improve acoustic performance, any cavities between the flexible substrate <NUM> and the surface of the support member <NUM> are filled with a backing material <NUM>. The liquid backing material <NUM> can be introduced between the flexible substrate <NUM> and the support member <NUM> via passageways <NUM> in the stands <NUM>, <NUM>, or through additional recesses as will be discussed in more detail hereafter. In some embodiments, suction can be applied via the passageways <NUM> of one of the stands <NUM>, <NUM>, while the liquid backing material <NUM> is fed between the flexible substrate <NUM> and the support member <NUM> via the passageways <NUM> of the other of the stands <NUM>, <NUM>. The backing material can be cured to allow it to solidify and set. In various embodiments, the support member <NUM> includes more than two stands <NUM>, <NUM>, only one of the stands <NUM>, <NUM>, or neither of the stands. In that regard the support member <NUM> can have an increased diameter distal portion <NUM> and/or increased diameter proximal portion <NUM> that is sized and shaped to elevate and support the distal and/or proximal portions of the flexible substrate <NUM>.

The support member <NUM> can be substantially cylindrical in some embodiments. Other shapes of the support member <NUM> are also contemplated including geometrical, non-geometrical, symmetrical, non-symmetrical, cross-sectional profiles. As the term is used herein, the shape of the support member <NUM> may reference a cross-sectional profile of the support member <NUM>. Different portions of the support member <NUM> can be variously shaped in other embodiments. For example, the proximal portion <NUM> can have a larger outer diameter than the outer diameters of the distal portion <NUM> or a central portion extending between the distal and proximal portions <NUM>, <NUM>. In some embodiments, an inner diameter of the support member <NUM> (e.g., the diameter of the lumen <NUM>) can correspondingly increase or decrease as the outer diameter changes. In other embodiments, the inner diameter of the support member <NUM> remains the same despite variations in the outer diameter.

A proximal inner member <NUM> and a proximal outer member <NUM> are coupled to the proximal portion <NUM> of the support member <NUM>. The proximal inner member <NUM> and/or the proximal outer member <NUM> can comprise a flexible elongate member. The proximal inner member <NUM> can be received within a proximal flange <NUM>. The proximal outer member <NUM> abuts and is in contact with the proximal end of flexible substrate <NUM>. A distal tip member <NUM> is coupled to the distal portion <NUM> of the support member <NUM>. For example, the distal member <NUM> is positioned around the distal flange <NUM>. The tip member <NUM> can abut and be in contact with the distal end of flexible substrate <NUM> and the stand <NUM>. In other embodiments, the proximal end of the tip member <NUM> may be received within the distal end of the flexible substrate <NUM> in its rolled configuration. In some embodiments there may be a gap between the flexible substrate <NUM> and the tip member <NUM>. The distal member <NUM> can be the distal-most component of the intraluminal imaging device <NUM>.

One or more adhesives can be disposed between various components at the distal portion of the intraluminal imaging device <NUM>. For example, one or more of the flexible substrate <NUM>, the support member <NUM>, the distal member <NUM>, the proximal inner member <NUM>, and/or the proximal outer member <NUM> can be coupled to one another via an adhesive.

<FIG> is a side view of an embodiment of a support member <NUM>, according to aspects of the present disclosure. Support member <NUM> may exhibit similar characteristics as support member <NUM> shown in <FIG>. For example, the support member <NUM> can be referenced as a unibody in some instances. The support member <NUM> may also be composed of a metallic material, such as stainless steel, gold, silver, copper, and/or alloy, or a non-metallic material, such as a plastic or polymer as previously described in relation to support member <NUM>. The support member <NUM> can be ferrule having a distal portion <NUM> and a proximal portion <NUM>. Support member <NUM> may also comprise a distal flange or end <NUM> and proximal flange or end <NUM>. The support member <NUM> may also be manufactured according to any suitable process. These processes may be substantially similar to manufacturing processes of support member <NUM>. Support member <NUM> may comprise one or more stands extending radially from support member <NUM>. These stands may be substantially similar to stands <NUM> and <NUM> and may serve similar functions. Support member <NUM> may comprise additional or fewer stands depending on the specific application of a particular embodiment. Support member <NUM> may be of any suitable shape. As shown in <FIG>, one embodiment of support member <NUM> may be generally cylindrical in shape. Other shapes of the support member <NUM> are fully contemplated including geometrical, non-geometrical, symmetrical, and non-symmetrical cross-sectional profiles. Support member <NUM> may be of any suitable size. For example, support member <NUM> may be of sufficiently small diameter to maneuver through the coronary vasculature surrounding the human heart. In some embodiments, the support member <NUM> can be relatively larger for peripheral applications, to maneuver through vasculature in the legs, abdomen, neck, and other anatomies of the human body. In other embodiments in which the intraluminal imaging device is to be used to image still larger lumens, either within organic or inorganic lumens, the overall dimensions of support member <NUM> may be adjusted and increased accordingly.

Also depicted in <FIG> are multiple stands in addition to stand <NUM>. As previously mentioned, support member <NUM> may comprise any number of stands of any suitable shape extending in an outward direction generally radially from the support member ferrule. In some embodiments, stand <NUM> may be positioned at a location near the distal end <NUM> of support member <NUM> and support member <NUM> may additionally comprise a proximal stand <NUM> positioned near the proximal end <NUM> of support member with an intermediate stand <NUM> positioned therebetween. These three stands, the distal stand <NUM>, the intermediate stand <NUM>, and the proximal stand <NUM>, may serve various purposes or functions within ultrasound imaging assembly <NUM>. One purpose of distal stand <NUM>, intermediate stand <NUM>, and proximal stand <NUM> may be to provide support for flexible substrate <NUM>. In addition, intermediate stand <NUM> may be placed at a location proximal to the transducers <NUM> disposed on the surface of flexible substrate <NUM>.

Distal stand <NUM> and intermediate stand <NUM> define a region <NUM> extending longitudinally along the support member <NUM>. Transducers <NUM> on flexible substrate <NUM> may be positioned over region <NUM> such that transducers <NUM> are situated generally at the same longitudinal position as region <NUM> and radially outward from region <NUM>. The ferrule surface of support member <NUM> at region <NUM> between distal stand <NUM> and intermediate stand <NUM> may comprise one or more recesses <NUM>. Recesses <NUM> may be configured to extend completely through the exterior of support member <NUM> to the interior or inner lumen <NUM> within support member <NUM>. Recesses <NUM> may thereby allow direct access to the inner lumen <NUM> of support member <NUM> from the exterior environment of support member <NUM> and vice versa. One function of recesses <NUM> may be to introduce acoustic backing material <NUM> (<FIG>) to be positioned within the lumen created by distal stand <NUM>, intermediate stand <NUM>, region <NUM> and the inner surface of flexible substrate <NUM>. Acoustic backing material <NUM> may be used to attenuate signals which may propagate from transducers <NUM> of flexible substrate <NUM> in an inwardly radial direction. Acoustic backing material <NUM> may also attenuate reflected waves received by transducers <NUM> which may propagate from a source radially inward of transducers <NUM>. Due to these acoustic properties, acoustic backing material is positioned radially inward of transducers <NUM>. Intermediate stand <NUM> may serve as a barrier between region <NUM> filled with acoustic backing material <NUM> and region <NUM> which may not need to be filled with acoustic backing material <NUM>.

Intermediate stand <NUM> and proximal stand <NUM> may define region <NUM> extending longitudinally along the support member <NUM>. Integrated circuit controller chip(s) 206A and 206B may be positioned over region <NUM> such that integrated circuit controller chip(s) 206A and 206B are situated generally at the same longitudinal position as region <NUM> and radially outward from region <NUM>. The ferrule surface of support member <NUM> at region <NUM> between intermediate stand <NUM> and proximal stand <NUM> may comprise one or more recesses <NUM>. Recesses <NUM> may be configured to extend completely through the exterior of support member <NUM> to the interior or inner lumen <NUM> within support member <NUM>. Recesses <NUM> may thereby allow direct access to the inner lumen <NUM> of support member <NUM> from the exterior environment of support member <NUM> and vice versa. One function of recesses <NUM> may be to introduce filling material <NUM> (<FIG>) to be positioned within the lumen created by intermediate stand <NUM>, proximal stand <NUM>, region <NUM> and the inner surface of flexible substrate <NUM>. Region <NUM> may be composed of any suitable metallic or non-metallic material. In some embodiments, region <NUM> may be filled with an underfill material to the support the chips 206A and 206B. The underfill material can be an adhesive, an epoxy, etc. In some embodiments, the underfill material need not have acoustic attenuating properties as the acoustic backing material <NUM> because the underfill material is under the chips 206A, 206B, and not the transducers <NUM>. Filling material <NUM> may serve to physically support flexible substrate <NUM> generally around region <NUM>. Filling material <NUM> may be positioned at a location radially inward of integrated circuit controller chip(s) 206A and 206B as well as other components previously mentioned that may be positioned on the surface of flexible substrate <NUM>.

Also depicted in <FIG> is recess <NUM> positioned near the distal end <NUM> of support member <NUM>. As will be discussed in reference to <FIG>, recess <NUM> may extend completely through the exterior of support member <NUM> to the interior or inner lumen <NUM> within support member <NUM>. Recess <NUM> may thereby allow direct access to the inner lumen <NUM> of support member <NUM> from the exterior environment of support member <NUM> and vice versa.

<FIG> is a diagrammatic cross-sectional view of the distal portion of an ultrasound imaging assembly <NUM> before a tip member <NUM> (<FIG>) is coupled to the ultrasound imaging assembly <NUM>, according to aspects of the present disclosure. Ultrasound imaging assembly <NUM> may be substantially similar to ultrasound imaging assembly <NUM> previously presented or may differ. As shown in <FIG>, ultrasound imaging assembly <NUM> may comprise support member <NUM>. Support member <NUM> can be tubular in shape and define a lumen <NUM> extending longitudinally therethrough. The lumen <NUM> can be sized and shaped to receive the guide wire <NUM>. Lumen <NUM> may further be configured to receive inner member <NUM> therethrough.

Support member <NUM> may further comprise a stand <NUM>. Stand <NUM> may extend radially from support member <NUM>. Stand <NUM> may also be referred to as a lip or shoulder. Stand <NUM> and support member <NUM> may be integrally formed as a unitary structure, while in other embodiments, stand <NUM> may be formed of a different component than support member <NUM>. Stand <NUM> may be fixedly coupled to support member <NUM>. In different embodiments, stand <NUM> may be manufactured of different materials than support member <NUM>, or the same materials. In any case, stand <NUM> may be manufactured of any suitable material, including metallic and non-metallic materials depending on the specific application of a particular embodiment. Stand <NUM> may be of any suitable shape. For example, stand <NUM> may be generally circular extending completely around and in direct contact with support member <NUM>. In other embodiments, stand <NUM> may be replaced with multiple components spaced a distance apart from one another and positioned at the same longitudinal position around support member <NUM>. In addition, stand <NUM> may extend any suitable distance from support member <NUM>.

Ultrasound imaging assembly <NUM> may further comprise flexible substrate <NUM>. Flexible substrate <NUM> may be fixedly coupled to the outer surface of stand <NUM> in such a way that stand <NUM> may support flexible substrate <NUM>. Flexible substrate <NUM> may thereby be positioned at an appropriate space away from support member <NUM> so as to create a gap between these two components. This gap is created by stands which may be substantially similar to stand <NUM>, stand <NUM>, stand <NUM>, or stand <NUM> which extend radially outward from the ferrule of support member <NUM> in such a way that the outer diameter of the stands is greater than the overall diameter of the support member <NUM> ferrule. This gap may be filled with any suitable materials or components, including but not limited to an acoustic backing material <NUM>, filling material <NUM> (<FIG>), other attenuating material, or any suitable material. In the particular embodiment shown in <FIG>, the gap between flexible substrate <NUM> and support member <NUM> as defined by stand <NUM> is filled with acoustic backing material <NUM>. To improve acoustic performance, any cavities between the flexible substrate <NUM> and the surface of the support member <NUM> are generally filled with a backing material <NUM>. The liquid backing material <NUM> has a relatively low acoustic impedance, and can be introduced between the flexible substrate <NUM> and the support member <NUM> via passageways in the support member <NUM> (not shown). Backing material <NUM> may be used to attenuate or absorb acoustic energy not directed to the anatomy of interest. The backing material <NUM> fills the space between the support member <NUM> and the transducer array <NUM> as well as the gaps between adjacent individual transducers <NUM>. The backing material <NUM> possesses the ability to highly attenuate the ultrasound which is transmitted by the transducer array <NUM>. The backing material <NUM> also provides support for the transducer elements. The backing material <NUM> can be cured to allow it to solidify and set in a sufficiently short period of time to meet manufacturing needs. A number of known materials meeting the above described criteria for a good backing material will be known to those skilled in the art. An example of such a backing material comprises a mixture of epoxy, hardener and phenolic microballoons providing high ultrasound signal attenuation and satisfactory support for the ultrasound transducer assembly. Still other materials for baking material <NUM> may include polymers, graphite, composites, ceramics, metals, or any combination thereof.

In some embodiments, positioned at the distal portion <NUM> of support member <NUM>, support member <NUM> may comprise a plurality of recesses <NUM>. In its cross-sectional view, support member <NUM> is pictured comprising two such recesses <NUM>. However, support member <NUM> may comprise only one, three, four, or more recesses <NUM>. In an embodiment, recess <NUM> may extend completely through the distal portion <NUM> of support member <NUM>. For example, recess <NUM> may extend from surface <NUM> of recess <NUM> completely through a portion of support member <NUM> to the opposing surface <NUM> of support member <NUM>. In this configuration, recess <NUM> allows for direct access to or exposes inner member <NUM>. In other embodiments, however, recess <NUM> may not extend completely through support member <NUM> such that recess <NUM> does not expose inner member <NUM>. In such an embodiment, recess <NUM> may only be configured on surface <NUM> of support member <NUM>. Opposing surface <NUM> would not comprise any such recess, but would be substantially uniform. In still other embodiments, support member <NUM> may comprise some recesses which extend completely through support member <NUM>, and some recesses which do not extend completely through support member <NUM>. Recess <NUM> may be of any suitable size or shape. In some embodiments, recess <NUM> is of a generally circular shape. In other embodiments, the shape of recess <NUM> may be that of a rectangle, square, triangle, or any other polygon. Other shapes are also contemplated including geometrical, non-geometrical, symmetrical and non-symmetrical shapes. Recess <NUM> may also be referred to as a hole or cavity.

<FIG> is a diagrammatic cross-sectional view of a tip member <NUM>, according to aspects of the present disclosure. Tip member <NUM> may also be referred to as a molded tip or lead tip. Tip member <NUM> may be constructed of any suitable material including a non-metallic material, such as a plastic or polymer. In some embodiments, tip member <NUM> is the leading component of intraluminal imaging device <NUM> while the device travels through a body lumen. Tip member <NUM> may be composed of any appropriate material, but may be flexible so as to not penetrate the body lumen. Tip member <NUM> may comprise a distal end <NUM> and a proximal end <NUM>. Tip member <NUM> may also be of a generally conical shape. However, tip member <NUM> may be of any suitable shape configured to allow an intraluminal imaging device to easily maneuver through the vasculature of a patient. In addition, tip member <NUM> may be of any suitable size configured to accomplish the desired result in any particular application. The overall diameter of tip member <NUM> at a distal end <NUM> may be smaller than the overall diameter of tip member <NUM> at a proximal end <NUM>. In addition, the overall diameter of tip member <NUM> at a proximal point <NUM> may be smaller than the overall diameter of tip member <NUM> at a point <NUM> positioned between distal end <NUM> and proximal end <NUM>. Tip member <NUM> may then further comprise two sloped or tapered surfaces, surface <NUM> and surface <NUM> sloping in opposite directions from one another. In other words, surface <NUM> and surface <NUM> comprise opposite tapers. For example, surface <NUM> and surface <NUM> may extend towards the radial center of tip member <NUM> and away from point <NUM>. Point <NUM> also need not be a singular longitudinal point along tip member <NUM>. In other embodiments, there may be a larger region of substantially the same outer diameter in place of point <NUM>. In still other embodiments, tip member <NUM> may not comprise surface <NUM>. For example, the overall diameter of proximal end <NUM> may be the largest overall diameter at any longitudinal location of tip member <NUM> making tip member <NUM> a purely conical shape.

Tip member <NUM> may further define an inner lumen <NUM>. Lumen <NUM> may comprise a space between the outer surfaces of tip member <NUM> and may be configured to receive inner member <NUM>. The overall diameter of inner lumen <NUM> may be substantially similar to the diameter of inner member <NUM> or may be larger depending on the application so as to allow additional components to be received within lumen <NUM>.

Tip member <NUM> may further comprise a plurality of protrusions <NUM> which extend from an inner surface <NUM> of tip member <NUM> in an inward direction towards the radial center of tip member <NUM> and protruding into lumen <NUM>. In other embodiments, tip member <NUM> may comprise only one such protrusion <NUM>, or may comprise two, three, four, or more protrusions <NUM>. The dimensions of protrusion <NUM> may be of any suitable dimension and may be configured to correspond to or be received by recesses <NUM> of support member <NUM>. In an embodiment, protrusion <NUM> may have a generally circular cross-sectional profile shape. In still other embodiments, it is fully contemplated that cross-sectional profiles of a rectangle, square, triangle, other polygon, and geometrical, non-geometrical, symmetrical and non-symmetrical shapes may be used for protrusion <NUM>. In addition, though <FIG> presents protrusion <NUM> extending in a direction directly towards the radial center of tip member <NUM>, in other embodiments, protrusion <NUM> may extend at any suitable angle, e.g. an oblique angle or the like, in an inward, radial direction. In addition, the overall width of protrusion <NUM> need not be uniform. In addition, protrusion <NUM> and tip member <NUM> may be integrally formed as a unitary structure, while in other embodiments protrusion <NUM> and tip member <NUM> may be formed of different components. As such, protrusion <NUM> may be constructed of a different material than tip member <NUM> or may be constructed of the same material.

<FIG> is a diagrammatic cross-sectional view of the connection of the distal end of the ultrasound imaging assembly <NUM> shown in <FIG> and the proximal end of the tip member <NUM> shown in <FIG>, according to aspects of the present disclosure. The diameter of tip member <NUM> at proximal end <NUM> may be smaller than the overall diameter of the lumen created by flexible substrate <NUM> in its rolled configuration, such that the proximal end <NUM> may be received inside the distal portion of flexible substrate <NUM> in its rolled configuration, as shown in <FIG>. In this configuration and as also shown in <FIG>, the distal end or flange <NUM> of support member <NUM> is received within lumen <NUM> (<FIG>) of tip member <NUM>. The proximal end <NUM> of tip member <NUM> may be in direct contact with and abut stand <NUM> of support member <NUM>. In other embodiments, proximal end <NUM> of tip member <NUM> may not abut stand <NUM> but may positioned at a location distal of stand <NUM> so as to create a gap.

When tip member <NUM> is placed in connection or direct contact with ultrasound imaging assembly <NUM>, protrusions <NUM> of tip member <NUM> may be received into corresponding recesses <NUM> of support member <NUM>. Protrusions <NUM> may be of the same cross-sectional profile shape as recesses <NUM> or may be of a different cross-sectional profile shape. Though <FIG> depicts two such protrusions <NUM> and two corresponding recesses <NUM>, there may be more or fewer protrusions <NUM> and corresponding recesses <NUM>. In addition, though both protrusions <NUM> and recesses <NUM> depicted in <FIG> are positioned at the same longitudinal location along ultrasound imaging assembly <NUM>, this need not be the case. For example, in other embodiments, a protrusion <NUM> located on tip member <NUM> and a corresponding recess <NUM> located on support member <NUM> may be located at a point proximal or distal to another protrusion <NUM> and corresponding recess <NUM>.

In some embodiments, protrusion <NUM> may extend completely through recess <NUM> such that the distal end of protrusion <NUM> is in direct contact with the outer surface of inner member <NUM>. Tip member <NUM>, including protrusion <NUM> may also be of the same material as inner member <NUM>. This embodiment provides a strong mechanical bond between support member <NUM> and tip member <NUM>. As previously stated, in other embodiments, recess <NUM> may not extend completely through support member <NUM> from surface <NUM> to surface <NUM>. In these embodiments, recess <NUM> may only be positioned on surface <NUM> and surface <NUM> may be substantially uniform. In these embodiments, the proximal end of protrusion <NUM> would not extend completely through support member <NUM> and would not be in direct contact with the outer surface of inner member <NUM>. A mechanical bond would still be formed between support member <NUM> and tip member <NUM> in this embodiment.

In some embodiments, a protrusion may be positioned at the distal region of support member <NUM> and a corresponding recess may be positioned on tip member <NUM>. In such an embodiment, the protrusion may be of similar geometry to protrusion <NUM>. However, the protrusion may extend radially outward from the ferrule of support member <NUM> and may be of the same material as support member <NUM> such that the protrusion and support member <NUM> are one unitary structure. The protrusion may also be of a different material. The protrusion may be positioned on surface <NUM> of support member <NUM>. A recess positioned on the tip member <NUM> may receive the protrusion.

In an embodiment in which protrusion <NUM> extends completely through support member <NUM> and is direct contact with inner member <NUM>, ultrasound imaging assembly <NUM> may be subject to a reflow process after assembly. This reflow process may be substantially similar to reflow processes known and readily available to those skilled in the art. During such a reflow process, the temperature of the surrounding environment of ultrasound imaging assembly <NUM> may be increased above the melting point of the materials used to construct protrusion <NUM> of tip member <NUM> and inner member <NUM>, but be kept below the melting point of other components of ultrasound imaging assembly <NUM> including but not limited to support member <NUM>, flexible substrate <NUM>, and others. In some embodiments, the flexible substrate <NUM> may be composed of a thermal set material that will not melt during reflow, such as Kapton® or any other suitable material. The range of settings during a reflow process may be configured based on visual inspection by a manufacturer of the ultrasound imaging assembly <NUM>. In some embodiments, the range of settings during a reflow process may comprise the temperature of the environment during reflow, the areas or parts of ultrasound imaging assembly <NUM> to be included in the reflow process, or other features or characteristics. Other components may also be shielded to avoid melting during a reflow process. In some embodiments, shielding components may not be necessary due to characteristics and/or properties of the heat generating element used during a reflow process. For example, the travel distance of the heat may depend on the length of the heated die. During this reflow process, protrusion <NUM> and inner member <NUM> may begin a phase transition from a substantially solid material to a liquid material such that, once the temperature cools, the two components fuse together becoming one unitary structure and ensuring a very strong bond between tip member <NUM>, inner member <NUM>, and support member <NUM>. In some embodiments in which protrusion <NUM> is constructed of a different material than tip member <NUM>, protrusion <NUM> alone fuses with inner member <NUM> such that they become a unitary structure. The material of protrusion <NUM> may be selected with a melting point below the environmental temperature of the ultrasound imaging assembly <NUM> during the reflow process and the material of tip member <NUM> may be selected with a melting point above the environmental temperature. In this embodiment, only protrusion <NUM> may phase transition and fuse to inner member <NUM> while tip member <NUM> may retain its original shape.

At some point after tip member <NUM> is positioned in contact with support member <NUM> and ultrasound imaging assembly <NUM>, and either before or after the reflow process previously described, adhesive <NUM> may be applied to the distal connection between tip member <NUM> and ultrasound imaging assembly <NUM>. Adhesive <NUM> may fill gaps left between the outer surface <NUM> of tip member <NUM> and the inner surface of flexible substrate <NUM> in its rolled configuration. Adhesive <NUM> may also fill gaps left between the inner surface <NUM> of tip member <NUM> and surface <NUM> (<FIG>) of support member <NUM> and may extend distally within tip member <NUM>. Adhesive <NUM> may be any particular type of suitable adhesive, such as epoxy, cyanoacrylate, urethane adhesive, and/or acrylic adhesives, as well as others. Adhesive <NUM> may be liquid of any suitable viscosity. In some embodiments, adhesive <NUM> is not light cured (e.g., not UV cured).

<FIG> is a partial cutaway view of another embodiment of the connection of the distal end of a support member <NUM> and the proximal end of a tip member <NUM>, according to aspects of the present disclosure. Support member <NUM> may be similar to support member <NUM> presented previously and may serve similar functions as support member <NUM>. Support member <NUM> may also be referred to as a unibody. Similar to support member <NUM>, support member <NUM> may also be composed of a metallic material, such as stainless steel, or a non-metallic material. The support member <NUM> can be ferrule and may be manufactured according to any suitable process. Support member <NUM> may comprise one or more stands <NUM> extending radially from support member <NUM>. These stands may be substantially similar to stands <NUM>, <NUM> and <NUM> and may serve similar functions. Support member <NUM> may be of any suitable size.

In some embodiments, as shown in <FIG>, support member <NUM> may comprise a recess <NUM> at the distal portion <NUM> of support member <NUM>. Recess <NUM> may be substantially similar to recess <NUM> presented in <FIG>. Like recess <NUM>, recess <NUM> may be of any suitable shape. For example, as shown in <FIG>, recess <NUM> may be of a generally oval shape. In other embodiments, recess <NUM> may be circular, or have a cross-sectional profile of any other suitable shape. Recess <NUM> may extend completely through the surface of support member <NUM> such that the outer environment of support member <NUM> may be in direct contact with the inner lumen within the axial center of support member <NUM>. Recess <NUM> may receive a protrusion positioned on the inner surface of tip member <NUM>. Such a protrusion may be substantially similar to protrusion <NUM>. Recess <NUM> may allow a protrusion on the inner surface of tip member <NUM> to come into direct contact with the outer surface of inner member <NUM>.

In some embodiments, as shown in <FIG>, support member <NUM> may further comprise one or more ridges <NUM> positioned around the outer surface of the distal portion <NUM> of support member <NUM>. Ridges <NUM> may also be referred to as barbs, spikes, anchors, flanges, collars, or ribs. In some embodiments, ridges <NUM> and support member <NUM> may be integrally formed as a unitary structure. Ridges <NUM> may be of any suitable shape. As shown in <FIG>, in some embodiments, ridges <NUM> may comprise two outer surfaces, distal surface <NUM> and proximal surface <NUM>. Distal surface <NUM> may be sloped such that the outer diameter of support member <NUM> is substantially similar to the overall outer diameter of support member <NUM> at a distal point of a ridge <NUM> of support member <NUM> and then gradually increases to a larger diameter at a proximal point on ridge <NUM>. Surface <NUM> may extend in a substantially orthogonal direction to the outer surface of support member <NUM> as shown in <FIG>. This configuration of a sloped distal surface <NUM> and an oblique proximal surface <NUM> results in a more secure connection between tip member <NUM> and support member <NUM> by allowing tip member to move in a proximal direction, as indicated by arrow <NUM>, when being connected to support member <NUM> but not allowing tip member to move in a distal direction, as indicated by arrow <NUM>. In other embodiments, surface <NUM> may be a sloped surface as well. In still other embodiments, ridges <NUM> may comprise additional surfaces and may be of any suitable cross-sectional shape. For example, the cross-sectional profile of ridges <NUM> may be substantially rectangular or semi-circular among other geometric and non-geometric shapes. In some embodiments, ridges <NUM> may extend completely around the outer surface of support member <NUM> at a longitudinal point along support member <NUM>. In other embodiments, ridges <NUM> may only extend partially around outer surface of support member <NUM>. For example, ridges <NUM> may extend around substantially half of the outer surface of support member <NUM>, substantially a quarter of the outer surface of support member <NUM> or around any other suitable portion of support member <NUM>. In addition, at the same longitudinal point along support member <NUM>, there may be positioned more than one such ridge <NUM> extending along some fraction of the outer circumference of support member <NUM>.

As shown in <FIG>, the support member <NUM> can include multiple ridges <NUM>. Three such ridges <NUM> are depicted in <FIG>, however, fewer or more ridges <NUM> may be used in the design of support member <NUM>. For example, one, two, three, four, five, or more ridges <NUM> may be placed along the outer surface of the distal portion <NUM> of support member <NUM>. Ridges <NUM> may be in any position relative to recess <NUM>. As shown in <FIG>, recess <NUM> may overlap with one or more of ridges <NUM>, however, in other embodiments, recess <NUM> may be positioned between, proximal or distal of one or more ridges <NUM>.

As also shown in <FIG>, tip member <NUM> may comprise one or more grooves <NUM>. Grooves <NUM> may also be referred to as troughs, channels, indentations, notches, or other suitable terms. In some embodiments, grooves <NUM> may be of a substantially similar shape as ridges <NUM> such that ridges <NUM> may be received into grooves <NUM> when the proximal end of tip member <NUM> is brought into contact with the distal end of support member <NUM>. As with ridges <NUM>, grooves <NUM> be of any suitable cross-sectional shape. For example, the cross-sectional profile of grooves <NUM> may be substantially rectangular or semi-circular among other geometric and non-geometric shapes, Similarly, grooves <NUM> may extend completely around the inner surface of tip member <NUM> at a longitudinal point along tip member <NUM>. In other embodiments, grooves <NUM> may only extend partially around inner surface of the tip member <NUM>. In addition, at the same longitudinal point along the inner surface of tip member <NUM>, there may be positioned more than one such groove <NUM> extending along some fraction of the inner circumference of tip member <NUM>. In addition, although three such grooves <NUM> are depicted in <FIG>, fewer or more grooves <NUM> may be used in the design of tip member <NUM>. For example, one, two, three, four, five, or more grooves <NUM> may be placed along the inner surface of the proximal portion of tip member <NUM>. Further, although not depicted in the partial cutaway view of tip member <NUM> in <FIG>, tip member <NUM> may comprise one or more protrusions substantially similar to protrusion <NUM> previously discussed. These protrusions may be positioned at any suitable location within the inner surface of tip member <NUM> and in any position relative to grooves <NUM>.

In another embodiment of the disclosed invention, the location of ridges <NUM> and grooves <NUM> may be reversed. For example, ridges may be located on the inner surface of the proximal portion of tip member <NUM>. These ridges may extend inwardly radially from the inner surface of tip member <NUM> so as to protrude into the inner lumen created by tip member <NUM>. In contrast, the distal portion <NUM> of support member <NUM> may comprise corresponding grooves similar to grooves <NUM> depicted in <FIG>. However, these grooves may be positioned on the outer surface of the distal portion <NUM> of support member <NUM> so as to create a recess or void extending inwardly radially into the outer surface of support member <NUM>.

In still other embodiments, the outer surface of support member <NUM> may comprise one or more of both ridges and grooves as previously described and the inner surface of tip member <NUM> may similarly comprise one or more of both ridges and grooves as previously described. This plurality of both ridges and grooves positioned on both support member <NUM> and tip member <NUM> may be configured to receive one another or interlock with one another creating a substantially stronger coupling of support member <NUM> and tip member <NUM>.

<FIG> is a flow diagram of a method <NUM> of a phase of assembling an intraluminal imaging device <NUM> according to an embodiment of the present disclosure. The method <NUM> can include mechanically coupling tip member <NUM> to intraluminal imaging device <NUM>. As illustrated, method <NUM> includes a number of enumerated steps, but embodiments of method <NUM> may include additional steps before, after, or in between the enumerated steps. In some embodiments, one or more of the enumerated steps may be omitted, performed in a different order, or performed concurrently. The steps of method <NUM> can be carried out by a manufacturer of the intraluminal imaging device <NUM> and/or a manufacturer of any other component discussed in the present disclosure. Method <NUM> will be described with reference to <FIG>, which are side views of various components of the ultrasound imaging assembly <NUM> during various steps of manufacturing. For example, <FIG> illustrate assembly steps for various components of the ultrasound imaging assembly <NUM>, such as the connection between the intraluminal imaging device <NUM> and the tip member <NUM>.

At step <NUM>, method <NUM> includes positioning scanner assembly or ultrasound imaging assembly <NUM> around an assembly mandrel <NUM> (<FIG>). An assembly mandrel <NUM> may be used to support the ultrasound imaging assembly <NUM> during various stages of manufacturing. Assembly mandrel <NUM> may be of any suitable length. The diameter of assembly mandrel <NUM> may correspond to the inner diameter of the inner member <NUM> or may differ. In other embodiments, ultrasound imaging assembly <NUM> may be constructed without the use of assembly mandrel <NUM>. Assembly mandrel <NUM> may also be referred to as a support shaft or support rod. Assembly mandrel <NUM> may be constructed of any suitable material, including metallic and non-metallic materials. In addition, assembly mandrel <NUM> may be a rigid structure or semi-rigid structure.

At step <NUM>, method <NUM> includes positioning tip member <NUM> around assembly mandrel <NUM> at some point distal to scanner assembly or ultrasound imaging assembly <NUM> as shown in <FIG> is a side view of the intraluminal imaging device <NUM> and tip member <NUM> positioned around an assembly mandrel <NUM> before coupling the tip member <NUM> to the scanner assembly <NUM>, according to aspects of the present disclosure.

At step <NUM>, method <NUM> includes positioning the proximal portion of tip member <NUM> within the distal portion of ultrasound imaging assembly or scanner assembly <NUM> and interlocking protrusions <NUM> of tip member <NUM> with corresponding recesses <NUM> of support member <NUM> as shown in <FIG> is a side view of the ultrasound imaging assembly or scanner assembly <NUM> and a tip member <NUM> positioned around an assembly mandrel <NUM> after coupling the tip member <NUM> to the scanner assembly <NUM>, according to aspects of the present disclosure. As previously discussed, when tip member <NUM> is placed in connection or direct contact with scanner assembly <NUM>, protrusions <NUM> of tip member <NUM> may be received into corresponding recesses <NUM> of support member <NUM> creating a strong mechanical connection between support member <NUM> and tip member <NUM>. Protrusions <NUM> may also be in direct contact with inner member <NUM> such that during a subsequent reflow process, protrusions <NUM> and inner member <NUM> fuse together and becoming a unitary structure.

At step <NUM>, method <NUM> includes applying adhesive <NUM> to the distal connection of the tip member <NUM> and ultrasound imaging assembly or scanner assembly <NUM>. Adhesive <NUM> may additionally be applied to the connection of tip member <NUM> and scanner assembly <NUM> and fill gaps between the outer surface <NUM> of tip member <NUM> and the inner surface of flexible substrate <NUM> in its rolled configuration and gaps between the inner surface <NUM> of tip member <NUM> and outer surface <NUM> of support member <NUM>. Adhesive <NUM> applied in such a manner may increase the strength of the connection between tip member <NUM> and ultrasound imaging assembly <NUM> as described in relation to <FIG>.

At step <NUM>, method <NUM> includes positioning a heat shrink layer <NUM> around tip member <NUM> and ultrasound imaging assembly or scanner assembly <NUM>. <FIG> is a side view of a heat shrink layer <NUM> positioned around an ultrasound imaging assembly or scanner assembly <NUM> and a tip member <NUM> supported by an assembly mandrel <NUM>, according to aspects of the present disclosure. A heat shrink layer <NUM> may be applied around the scanner assembly <NUM> and related components prior to a reflow process. Heat shrink layer <NUM> may be constructed of any one of a variety of thermoplastics, including polyolefin, polyvinyl chloride, polychloroprene (e.g., NEOPRENE®), among others. Heat shrink layer <NUM> may be positioned at a location around the outer surface of scanner assembly <NUM> and then subjected to increased temperature, causing heat shrink layer <NUM> to contract inwardly around scanner assembly <NUM>. Heat shrink layer <NUM> may be used to shield components such as the inner member <NUM>, outer member <NUM>, scanner assembly <NUM>, or other components that are incompatible with high temperature exposure during a reflow process. In some embodiments, heat shrink layer <NUM> may also serve other purposes as well. After a reflow process is completed, heat shrink layer <NUM> may be removed from the intraluminal imaging device.

At step <NUM>, method <NUM> includes increasing the temperature of the environment of the ultrasound imaging assembly or scanner assembly <NUM> to initiate a reflow process. As previously described, during a reflow process, the temperature of the surrounding environment of ultrasound imaging assembly or scanner assembly <NUM> may be increased above the melting point of the materials used to construct protrusion <NUM> of tip member <NUM> and inner member <NUM>, but be kept below the melting point of other components of scanner assembly <NUM>. Protrusion <NUM> and inner member <NUM> may then begin a phase transition such that the two components fuse together becoming one unitary structure and ensuring a very strong bond between tip member <NUM>, inner member <NUM> and support member <NUM>. In some embodiments, heat shrink layer <NUM> may be removed at this phase of assembly. In other embodiments, heat shrink layer <NUM> may not be removed. In some embodiments, additional steps may be performed to reach a final product including applying hydrophobic or hydrophilic coatings to various components or portions of the scanner assembly <NUM> and its associated components. Other steps may be taken in different embodiments as well.

<FIG> is a side view of an ultrasound imaging assembly or scanner assembly <NUM> after assembly, according to aspects of the present disclosure. Ultrasound imaging assembly or scanner assembly <NUM> is connected at a distal end to tip member <NUM> and connected at a proximal end to outer member <NUM>. Flexible substrate <NUM> is depicted in <FIG> wrapped around a support member. A plurality of conductors, transmission line bundle, or cables <NUM> are also depicted connected at a proximal end of scanner assembly <NUM> extending proximally from the assembly.

Embodiments of the presently disclosed invention may comprise protrusions and/or corresponding recesses/grooves at any suitable location of the intraluminal device. For example, one or more protrusion(s) and/or one or more recesses/grooves can be provided on tip member <NUM>, the scanner assembly <NUM>, the flexible substrate <NUM>, the support member <NUM>, the inner member <NUM>, and/or any other component described in the present application. The protrusions and/or recesses/grooves can have any suitable size and shape, orientation, and/or direction of extension (radially inward, radially outward, proximally, distally, obliquely, perpendicularly, etc.) For example, a flexible substrate <NUM> can include a protrusion that extends radially inward and is received within a recess/groove of the support member <NUM>, the tip member <NUM>, and/or the inner member <NUM>. For example, the inner member <NUM> can include a protrusion that extends radially outward and is received within a recess/groove of the flexible substrate <NUM>, the support member <NUM>, and/or the tip member <NUM>.

One or more embodiments of the present disclosure advantageously increase coupling strength between components. This advantageously ensures that the components cannot come apart. This improves patient safety by minimizing and/or eliminating the possibility of components separating while the intraluminal device is within the patient's body. Such strength can be added as the result of mechanical engagement between components (e.g., physical contact resulting from the protrusion of one component being received within a recess/groove of another component). In some embodiments, the material of multiple components can be joined together. For example, polymer material(s) can be fused or melted together during a reflow process. In some embodiments, the mechanical engagement between components is supported by adhesive surrounding and in contact with the joint.

<FIG> is a diagrammatic cross-sectional view of an embodiment of the connection between components at the distal portion of the intraluminal imaging device, according to aspects of the present disclosure. <FIG> includes a protrusion <NUM> of the tip member <NUM>. Protrusion <NUM> may be substantially similar to protrusion <NUM> previously mentioned or may differ. As shown in <FIG>, protrusion <NUM> may be configured to be received into recess <NUM> of support member <NUM>. Protrusion <NUM> may also be configured to be received into an additional recess <NUM> within inner member <NUM>, such that the tip of protrusion <NUM> may be in direct contact with lumen <NUM> created by inner member <NUM>. In other embodiments, recess <NUM> may not extend completely through inner member <NUM> as shown in <FIG>. For example, recess <NUM> may only extend part way through inner member <NUM> such as to extend into the outer surface of inner member <NUM> but not through the inner surface of inner member <NUM>. In either of these embodiments, however, during a reflow process, protrusion <NUM> fuses with inner member <NUM> so as to create a strong bond between the two components and forming one unitary structure.

<FIG> is a diagrammatic cross-sectional view of an embodiment of the connection between components at the distal portion of the intraluminal imaging device, according to aspects of the present disclosure. <FIG> includes a protrusion <NUM> of the tip member <NUM>. Protrusion <NUM> may be substantially similar to protrusion <NUM> and/or protrusion <NUM> previously mentioned or may differ. As shown in <FIG>, protrusion <NUM> may be configured to be received into recess <NUM> of inner member <NUM>. Recess <NUM> may be substantially similar to recess <NUM> previously mentioned. For example, recess <NUM> may extend completely through inner member <NUM> such that recess <NUM> may be detected on both the outer surface and inner surface of inner member <NUM>. In addition, in other embodiments, recess <NUM> may only extend part way through inner member <NUM> such as to extend into the outer surface of inner member <NUM> but not through the inner surface of inner member <NUM>. In either of these embodiments, however, during a reflow process, protrusion <NUM> fuses with inner member <NUM> so as to create a strong bond between the two components and forming one unitary structure. As shown in <FIG>, protrusion <NUM> may be positioned at some location distal of support member <NUM> so as to not extend through any recess on or within support member <NUM>. In some embodiments, the distal tip of support member <NUM> may abut protrusion <NUM>. In other embodiments, protrusion <NUM> may be spaced from the support member <NUM> so as not to be in contact with support member <NUM>.

<FIG> is a diagrammatic cross-sectional view of an embodiment of the connection between components at the distal portion of the intraluminal imaging device, according to aspects of the present disclosure. <FIG> includes a protrusion <NUM> of the tip member <NUM>. Protrusion <NUM> may be substantially similar to protrusion <NUM>, protrusion <NUM>, and/or protrusion <NUM> except that protrusion <NUM> may extend radially outward from the outward surface of tip member <NUM>. As shown in <FIG>, protrusion <NUM> may be configured to be received into recess <NUM> of flexible substrate <NUM>. Recess <NUM> may be substantially similar to recess <NUM> and/or recess <NUM> previously mentioned but may be positioned within support member <NUM>. For example, recess <NUM> may extend completely through flexible substrate <NUM> such that recess <NUM> may be detected on both the outer surface and inner surface of flexible substrate <NUM>. In addition, in other embodiments, recess <NUM> may only extend part way through flexible substrate <NUM> so as to extend into the inner surface of flexible substrate <NUM> but not through the outer surface of flexible substrate <NUM>. In some embodiments, during a reflow process, protrusion <NUM> fuses with flexible substrate <NUM> so as to create a strong bond between the two components and forming one unitary structure. In other embodiments, protrusion <NUM> may not bond with flexible substrate <NUM> during a reflow process. Protrusion <NUM> may be positioned at any suitable location and a corresponding recess within flexible substrate <NUM> may be positioned at any suitable location within, on, or around scanner assembly <NUM>.

In other embodiments, an additional protrusion may extend from tip member <NUM> in a proximal direction towards stand <NUM> of support member <NUM>. Such a protrusion may be received into a corresponding recess positioned within stand <NUM> of support member <NUM>. Such a recess may be substantially similar to recess <NUM> of <FIG> or may differ. Such a configuration may provide a stronger connection between tip member <NUM> and the scanner assembly <NUM>. In some embodiments, a protrusion may extend distally from the stand <NUM> and be received within a recess of the tip member <NUM>.

While some embodiments are described in the context of an intraluminal ultrasound imaging device, it is understood that the present disclosure contemplates any type of intraluminal device (e.g., catheter, guide wire, guide catheter, etc.). For example, the intraluminal device can include a pressure sensor, flow sensor, temperature sensor, and/or electrode(s). The intraluminal device can include any suitable type of optical sensor. Any type of intraluminal imaging is contemplated, including intraluminal devices with an optical coherence tomography (OCT) imaging element and/or an intracardiac echocardiography (ICE) transducer array. One or more sensing devices of the intraluminal device can obtain physiological data (pressure, flow, temperature, images, etc.) associated with the body lumen in which intraluminal device is positioned. In some embodiments, the intraluminal device is a diagnostic device. In some embodiments, the intraluminal device is a therapeutic device that delivers a therapy to the body lumen. Such a therapeutic intraluminal device can have a treatment component at a distal portion (e.g., a balloon, an ablation electrode, a laser, an atherectomy blade, etc.).

Claim 1:
An intraluminal imaging device (<NUM>), comprising:
a flexible elongate member (<NUM>) configured to be positioned within a body lumen of a patient, the flexible elongate member comprising a proximal portion and a distal portion;
an ultrasound imaging assembly disposed at the distal portion of the flexible elongate member and configured to obtain ultrasound data while positioned within the body lumen; and
a tip member (<NUM>) coupled to the ultrasound imaging assembly, wherein the tip member comprises a polymer protrusion (<NUM>),
wherein the ultrasound imaging assembly comprises a recess (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) exposing a polymer portion of the ultrasound imaging assembly, and wherein the protrusion received within the recess is fused to the exposed polymer portion of the ultrasound imaging assembly to form a unitary structure.