Patent Description:
A wide variety of medical devices have been developed for medical use, for example, medical needles having sharp tips, such as biopsy needles. In some situations, it may be desirable to provide a medical device, assembly, or method for guarding and/or protecting the sharp distal tip of a medical needle.

<CIT> discloses methods and apparatus for selective surgical removal of tissue. Tissue may be ablated, resected, removed, or otherwise remodeled by standard small endoscopic tools delivered into the epidural space through an epidural needle. The sharp tip of the needle in the epidural space can be converted to a blunt tipped instrument for further safe advancement. Of the known medical devices and methods, each has certain advantages and disadvantages. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and using such medical devices.

This disclosure provides design, material, manufacturing method, and use alternatives for medical devices, for example, medical needle assemblies, expandable devices for use with medical needles, stylets for use with medical needles, and the like.

The present invention, in particular, relates to an expandable device for guarding a sharp distal tip of a needle defining a lumen. The expandable device includes an elongated tubular member including a body portion configured to be at least partially disposed within the needle lumen, and an expandable distal portion defining an inner lumen including an inner surface. The expandable distal portion is designed to shift between a first configuration in which the expandable distal portion has an outer diameter that is the same or less than the inner diameter of the needle lumen and a second configuration in which the expandable distal portion has an outer diameter that is greater than the inner diameter of the needle lumen and is configured to guard the sharp distal tip of the needle. The expandable device also includes an elongated inner member configured to be at least partially disposed within the inner lumen of the elongated tubular member and being configured to shift the expandable distal portion between the first configuration and the second configuration. The elongated inner member defines an outer surface, wherein the outer surface of the elongate inner member engages the inner surface of the expandable distal portion to shift the expandable distal portion from the first configuration to the second configuration.

Alternatively, or additionally to any of the embodiments above or below, wherein expandable distal portion is disposed distal of and adjacent to the sharp distal tip when in the second configuration such that the expandable distal portion guards the sharp distal tip of the needle.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated inner member defines an outer surface, wherein the outer surface of the elongate inner member engages the inner surface of the expandable distal portion to shift the expandable distal portion from the first configuration to the second configuration.

Alternatively, or additionally to any of the embodiments above or below, wherein the outer surface of the elongate inner member is engaged with the inner surface of the expandable distal portion when the expandable distal portion is in the second configuration.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated inner member defines an outer surface, wherein the outer surface of the elongate inner member disengages from the inner surface of the expandable distal portion to shift the expandable distal portion from the second configuration to the first configuration.

Alternatively, or additionally to any of the embodiments above or below, wherein the outer surface of the elongate inner member is disengaged from the inner surface of the expandable distal portion when the expandable distal portion is in the first configuration.

Alternatively, or additionally to any of the embodiments above or below, wherein the expandable distal portion has an inner diameter, and the elongated inner member has an outer diameter, and when in the first configuration, the outer diameter of the elongated inner member is greater than the inner diameter of the expandable distal portion.

Alternatively, or additionally to any of the embodiments above or below, wherein the inner member includes a proximal segment and a distal segment, and the distal segment includes the outer diameter that is greater than the inner diameter of the expandable distal portion, and the proximal segment includes an outer diameter that is less than the outer diameter of the distal segment.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated tubular member includes a proximal body portion having a first wall thickness, and the distal expandable portion has a second wall thickness that is greater than the first wall thickness.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated tubular member comprises a coil.

Alternatively, or additionally to any of the embodiments above or below, wherein the distal expandable portion comprises a coil.

Alternatively, or additionally to any of the embodiments above or below, wherein the distal expandable portion comprises a tubular body including an expansion relief slot formed therein.

Alternatively, or additionally to any of the embodiments above or below, wherein when in the second configuration the outer diameter of the expandable distal portion is greater than an outer diameter of the body portion.

An example embodiment includes a medical needle assembly including a needle having a needle body including a sharp distal tip and having a needle lumen defining an inner diameter. The assembly includes an elongated tubular member configured to be at least partially disposed within the needle lumen and including an expandable distal portion having an inner lumen defining an inner surface. The expandable distal portion is designed to shift between a first configuration in which the expandable distal portion has an outer diameter that is the same as or less than the inner diameter of the needle lumen and a second configuration in which the expandable distal portion has an outer diameter that is greater than the inner diameter of the needle lumen. The assembly includes an elongated inner member configured to shift the expandable distal portion from the first configuration to the second configuration.

The present disclosure further relates to a method of guarding a sharp tip of a needle having a needle lumen, which method does not fall under the wording of the claims and is merely provided for illustrative purposes. The method includes disposing an elongated tubular member having an expandable distal portion within the needle lumen such that the expandable distal portion is distal of the sharp tip, the expandable distal portion being in a first configuration in which the expandable distal portion has an outer diameter that is the same or less than an inner diameter of the needle lumen. The method further includes shifting the expandable distal portion to a second configuration in which the expandable distal portion has an outer diameter that is greater than the inner diameter of the needle lumen, wherein an elongated inner member is used to shift the expandable distal portion from the first configuration to the second configuration.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated inner member defines an outer surface and the expandable distal portion has an inner lumen defining an inner surface, wherein shifting the expandable distal portion from the first configuration to the second configuration includes engaging the outer surface of the elongate inner member with the inner surface of the expandable distal portion such that the outer diameter of the expandable distal portion increases.

Alternatively, or additionally to any of the embodiments above or below, further including shifting the expandable distal portion from the second configuration to the first configuration by disengaging the outer surface of the elongate inner member from the inner surface of the expandable distal portion such that the outer diameter of the expandable distal portion decreases.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated inner member is used to shift the expandable distal portion from the first configuration to the second configuration by moving the elongated inner member longitudinally into the inner lumen of expandable distal portion.

Alternatively, or additionally to any of the embodiments above or below, wherein the elongated inner member is used to shift the expandable distal portion from the second configuration to the first configuration by moving the elongated inner member longitudinally out of the inner lumen of expandable distal portion.

Another example embodiment includes a medical needle assembly including a needle having a needle body including a sharp distal tip and having a needle lumen. The assembly includes an elongated stylet including a proximal segment, a distal segment, and an intermediate segment, wherein the distal segment includes an elongated tapering stiffness profile, and the intermediate segment is stiffer than the distal segment. The stylet is disposed within the needle lumen such that the rigid intermediate segment is within the sharp distal tip, and the tapered distal segment extends distally beyond the sharp distal tip.

Additionally, when particular features, structures, and/or characteristics are described in connection with one embodiment, it should be understood that such features, structures, and/or characteristics may also be used in connection with other embodiments whether or not explicitly described unless clearly stated to the contrary.

Medical needles, such as biopsy, aspiration or delivery needles, are widely utilized throughout the world in medical procedures. Prior to or during use or during delivery, it may be desirable to guard and/or protect the sharp distal tip of a medical needle. For example, needles, such as biopsy needles, may be navigated to a target or treatment site through a delivery device and/or through the anatomy of a patient. It may be desirable to guard or protect the sharp needle tip during such navigation such that the tip does not undesirably skive, scrape, puncture or become embedded or stuck in the delivery device or in the anatomy. Once at the desired site, it may also be desirable to expose or "unguard" the sharp tip of the needle so that it may be used, for example, to take a biopsy sample or aspirate and/or deliver a fluid or material. As such, some embodiments of the present disclosure may include methods and devices that may be configured and used to selectively guard or protect a sharp needle tip when desired and may also be configured and used to selectively allow for exposure of the sharp needle tip for use as desired.

<FIG> shows a partial cross-sectional side view of one example embodiment of a medical needle assembly <NUM>. The medical needle assembly <NUM> includes a needle <NUM> having a needle body <NUM> defining a sharp distal tip <NUM>. The needle body <NUM> has an outer surface <NUM> and an inner surface <NUM> and defines a needle lumen <NUM> having an inner diameter D1. The sharp distal tip <NUM> defines a distal needle opening <NUM> into the needle lumen <NUM>. The needle <NUM> may be of any of a wide variety of medical needles, for example: a biopsy needle; an aspiration needle, such as a needle that may be used for fine needle aspiration; a delivery needle, such as a needle used for the delivery of therapeutic fluid and/or materials; or the like. In the particular embodiment shown, the needle <NUM> may be a biopsy needle. The sharp distal tip <NUM> and/or needle opening <NUM> may be configured to puncture and acquire a sample from tissue. Some example configurations for the sharp distal tip <NUM> include francine, lancet, beveled, and/or hubers tip configurations, or any other desired needle tip configuration that may be used, for example, in a biopsy and/or aspiration needle, or other type of medical needle. The needle <NUM> may include or be made of one or more metals, polymers, and/or composite or layered structures thereof, including any of those disclosed herein.

The medical needle assembly <NUM> also includes an expandable medical device for use with the needle <NUM>. The expandable medical device may be designed to have a first or non-expanded configuration, in which the medical device is configured to selectively allow movement of the needle <NUM> thereover, for example, to allow exposure of the sharp distal tip <NUM> when desired. The expandable medical device may be designed to have a second or expanded configuration, in which an expandable portion of the medical device is designed to guard and/or protect the sharp distal tip <NUM> when so desired. This embodiment includes an elongated tubular member <NUM> configured to be at least partially disposed within the needle lumen <NUM>. The elongated tubular member <NUM> includes a proximal body portion <NUM> and an expandable distal portion <NUM>, which is configured to shift between a first, radially non-expanded configuration and a second, radially expanded configuration, through the use of an elongated inner member <NUM>.

The proximal body portion <NUM> has an outer surface <NUM> and an inner surface <NUM>, which defines an inner lumen <NUM>. The proximal body portion <NUM> has a wall <NUM> having a first wall thickness which is defined between the outer surface <NUM> and the inner surface <NUM>. The proximal body portion <NUM> may have an outer diameter D5. The outer diameter D5 may be sized and/or configured such that the proximal body portion <NUM> may fit within, and/or be longitudinally movable within, the needle lumen <NUM>. For example, the proximal body portion <NUM> may have an outer diameter D5 that is less than the inner diameter D1 of the needle lumen <NUM>, such that the proximal body portion <NUM> may be disposed within the needle lumen <NUM>. The proximal body portion <NUM> may have an inner diameter D4, defined by the inner lumen <NUM>, which may be configured to accept another device therein, such as the elongated inner member <NUM>, as discussed in more detail below and herein. The proximal body portion <NUM> may include any structure as desired, such as a solid tubular member, extrusion, coil, braid, mesh, or the like. In the embodiment shown, the proximal body portion <NUM> comprises a solid tubular member. The proximal body portion <NUM> may include or be made of one or more metals, polymers, and/or composite or layered structures thereof, including any of those disclosed herein.

The expandable distal portion <NUM> has an inner surface <NUM> defining an inner lumen <NUM>, and an outer surface <NUM>. The inner lumen <NUM> may be connected to and/or in fluid communication with the inner lumen 31of the body portion <NUM>. The inner lumens <NUM> and <NUM> may be coaxial with one another and may be configured such that a device (such as the elongate inner member <NUM>) may extend and/or be moved longitudinally from one lumen (e.g. lumen <NUM>) into the other lumen (e.g. lumen <NUM>) when so desired. The expandable distal portion <NUM> has a wall <NUM> having a second wall thickness that is defined between the inner surface <NUM> and the outer surface <NUM>. In the embodiment shown, the second wall thickness (the wall thickness of the expandable distal portion <NUM>) is greater than the first wall thickness (the wall thickness of the proximal body portion <NUM>). The expandable distal portion <NUM> may have an outer diameter D2 and an inner diameter D3. The expandable distal portion <NUM> may be configured to radially expand and/or contract such that it can shift between a first, radially non-expanded configuration and a second, radially expanded configuration, as will be discussed in more detail below and herein. The expandable distal portion <NUM> may include any structure as desired, such as a tubular member, extrusion, coil, braid, mesh, or the like. In the embodiment shown, the expandable distal portion <NUM> comprises a coil member. The expandable distal portion <NUM> may include or be made of one or more metals, polymers, and/or composite or layered structures thereof, including any of those disclosed herein.

In the particular embodiment shown, the proximal body portion <NUM> and the expandable distal portion <NUM> are separate members that are connected together, for example via a bond, such as a weld, solder, braze, adhesive bond, mechanical bond or interlock, or the like, to create the elongated tubular member <NUM>. In other embodiments, however, the body portion <NUM> and the expandable distal portion <NUM> may be a single member and/or of unitary and/or monolithic construction. For example, elongated tubular member <NUM>, including the body portion <NUM> and the expandable distal portion <NUM>, may be a full length singular and/or monolithic structure, such as a tubular member, extrusion, coil, braid, mesh, or the like.

The elongated inner member <NUM> includes a proximal segment <NUM> and a distal segment <NUM> and has an outer surface <NUM> and an outer diameter D6. The outer diameter D6 may be sized and/or configured such that the elongated inner member <NUM> may fit within, and/or be longitudinally movable within, the inner lumen <NUM> of the proximal body portion <NUM>. For example, the elongated inner member <NUM> may have an outer diameter D6 that is less than the inner diameter D4 of the proximal body portion <NUM>, such that the elongated inner member <NUM> may be disposed within and/or longitudinally movable within the inner lumen <NUM>. In this embodiment, the proximal segment <NUM> and the distal segment <NUM> include the same outer diameter D6. However, in other embodiments, the outer diameter of the elongated inner member <NUM> may vary along its length between the proximal and distal segments, for example, as will be seen in other embodiments herein. The elongated inner member <NUM> is configured and/or arranged to shift the expandable distal portion <NUM> between the first, or radially non-expanded configuration and the second, or radially expanded configuration. For example, the elongated inner member <NUM> may include an outer diameter D6 that is larger than the inner diameter D3 of the expandable distal portion <NUM> when in the first, or radially non-expanded configuration. The elongated inner member <NUM> may be a solid or tubular structural member, and may take the form of such devices as a core member, a guidewire, a dilator, a trocar, an obturator, or the like, or any other such structural member or device.

As indicated herein, the expandable distal portion <NUM> is designed to shift between a first, radially non-expanded configuration, and a second, radially expanded configuration. <FIG> shows the expandable distal portion <NUM> in the first configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is the same as or less than the inner diameter D1 of the needle lumen <NUM>. In this configuration, the elongated inner member <NUM>, including the outer diameter D6, is disposed within the inner lumen <NUM> of the proximal body portion <NUM>, and is disposed proximal of the distal expandable portion <NUM>. As such, the outer surface <NUM> of the elongated inner member <NUM> is not engaged with and/or is disengaged from the inner surface <NUM> of the expandable distal portion <NUM>. The expandable distal portion <NUM> in this first configuration may have an outer diameter D2 that is configured to fit within, and/or be longitudinally movable within, the needle lumen <NUM>. As such, in this first configuration, the needle <NUM>, including the sharp distal tip <NUM>, may be longitudinally moved over and/or about the expandable distal portion <NUM>, and/or the expandable distal portion <NUM> may be moved within the needle <NUM> such that it is disposed within and/or movable within the needle lumen <NUM>. In this first configuration, the sharp needle tip may be considered to not be radially protected and/or guarded by the expandable distal portion <NUM>, relative to when in the second expanded configuration.

In this embodiment, when in the first configuration, the inner diameter D3 of the expandable distal portion <NUM> may be less than the inner dimeter D4 of the proximal body portion <NUM>. Additionally, the outer diameter D2 of the expandable distal portion <NUM> may be the same as the outer diameter D5 of the proximal body portion <NUM>. As can be appreciated, the variance in the wall thickness between the distal expandable portion <NUM> and the body portion <NUM> may allow this to be achieved. However, other embodiments may have different configurations. For example, it is contemplated that in some embodiments, when in the first configuration, the outer diameter D2 of the expandable distal portion <NUM> may be less than the outer diameter D5 of the proximal body portion <NUM>, as long as the expandable distal portion <NUM> has enough wall thickness to allow for adequate radial expansion of the outer diameter D2 when shifted to the second configuration (as discussed in more detail below).

<FIG> shows the expandable distal portion <NUM> in the second configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is larger than the inner diameter D1 of the needle lumen <NUM>. The elongated inner member <NUM> has been moved longitudinally in a distal direction and forced into the inner lumen <NUM> of the expandable distal portion <NUM> with a predetermined amount of force, such that the outer surface <NUM> of the elongated inner member <NUM> engages and/or is engaged with the inner surface <NUM> of the expandable distal portion <NUM>. Because the outer diameter D6 of the elongated inner member <NUM> is larger than the initial (e.g. non-expanded) inner diameter D3 of the expandable distal member <NUM>, as the elongated inner member <NUM> is inserted therein, it forces the expandable distal member <NUM> to expand radially. This radial expansion thus increased both the inner diameter D3 and outer diameter D2 of the expandable distal member <NUM> when in the second configuration relative to these diameters in the first configuration. As such, when in the second configuration, the inner diameter D3 of the expandable distal member <NUM> is about the same (or slightly less than) as the outer diameter D6 of the elongated inner member <NUM>, and the outer diameter D2 is larger than the inner diameter D1 of the needle lumen <NUM>. As such, the expandable distal portion <NUM> when in this second configuration may have an outer diameter D2 that is configured such that it cannot fit within and/or be longitudinally movable within, the needle lumen <NUM>. The expandable distal portion <NUM> is disposed adjacent to the sharp distal tip <NUM>, and now has a larger diameter D2, and thus may act to guard and/or protect the sharp distal tip <NUM>. As such, in this configuration, the sharp distal tip <NUM> may be considered to be radially protected and/or guarded by the expandable distal portion <NUM>.

In this embodiment, when in the second configuration, the outer diameter D2 of the expandable distal portion <NUM> may be larger than the outer diameter D5 of the proximal body portion <NUM>. Additionally, when in the second configuration, the inner diameter D3 of the expandable distal portion <NUM> may be the same as the inner dimeter D4 of the proximal body portion <NUM>. As can be appreciated, the variance in the wall thickness between the distal expandable portion <NUM> and the body portion <NUM> may allow this to be achieved. However, other embodiments may have different configurations. For example, it is contemplated that in some embodiments, when in the second configuration, the inner diameter D3 of the expandable distal portion <NUM> may be less than the inner dimeter D4 of the proximal body portion <NUM>, as long as the expandable distal portion <NUM> has enough wall thickness to allow for adequate radial expansion for the outer diameter D2 to be larger than the inner diameter D1 of the needle lumen <NUM> when in the second configuration.

The expandable medical device as disclosed herein can thus be used in a method of guarding the sharp tip of the needle <NUM>. The elongated tubular member <NUM> having the expandable distal portion <NUM> in the first configuration can be disposed within the needle lumen <NUM> such that the expandable distal portion <NUM> is distal of the sharp distal tip <NUM>, as shown in <FIG>. The expandable distal portion <NUM> can then be shifted to the to the second configuration, as shown in <FIG>, using the elongated inner member <NUM> to shift the expandable distal portion <NUM> from the first configuration to the second configuration.

The expandable distal portion <NUM> may be configured to be biased toward the first and/or unexpanded configuration. For example, when relaxed (e.g. without the application of the predetermined shifting force), the expandable distal portion <NUM> may be configured to be in the unexpanded configuration, for example as shown in <FIG>. The expandable distal portion <NUM> may include structure and/or be made of a material that may help achieve this. For example, expandable distal portion <NUM> may include structure and/or may be made of a resilient and/or elastic material that may allow for the expandable distal portion <NUM> to be mechanically and/or elastically biased to the first or unexpanded configuration. The expandable distal portion <NUM> may be shifted from the first configuration to the second configuration though the application of the predetermined shifting force (e.g. applied through the elongated inner member <NUM>), and then may mechanically and/or elastically reverted back and/or recover to the first configuration once the predetermined shifting force is removed (e.g. the elongated inner member <NUM> is removed from therein). The expandable distal portion <NUM> may include and/or be made of a tube, such as a slotted or cut tube, a winding, a braid, a coil, a mesh, or the like, which may be structurally configured to allow such elastic expansion and/or contraction. In the embodiment shown in <FIG> and <FIG>, the expandable distal portion <NUM> includes a coiled member that may include a spring force that may allow for radial expansion and contraction as desired.

In that regard, the expandable distal portion <NUM> may be shifted from the second, expanded configuration as shown in <FIG>, to the first, unexpanded configuration, as shown in <FIG>, by removing the predetermined expansion force applied by the elongated inner member <NUM>. For example, by moving the elongated inner member <NUM> longitudinally in a proximal direction out of the inner lumen <NUM> of the expandable distal portion <NUM>, the outer surface <NUM> of the elongated inner member <NUM> will disengage from the inner surface <NUM> of the expandable distal portion <NUM>. As such, the expandable distal portion <NUM> may revert and/or relax back to the first configuration, wherein the expandable distal portion <NUM> has an outer diameter D2 that is the same as or less than the inner diameter D1 of the needle lumen <NUM>, as shown in <FIG>.

As indicated herein, it may be desirable to guard and/or protect the sharp distal tip <NUM> of the needle <NUM> as the needle <NUM> is navigated to a target or treatment site through a delivery device and/or through the anatomy of a patient, such that the tip does not undesirably skive, scrape, puncture or become embedded or stuck in the delivery device or in the anatomy. It is then also desirable to expose or "unguard" the sharp distal tip <NUM> of the needle <NUM> for use at the target or treatment site. An example method of using the medical needle assembly <NUM> described above with reference to <FIG> and <FIG> will now be shown and described with reference to <FIG>.

<FIG> is a partial cross-sectional plan view showing a delivery device <NUM> advanced within the anatomy of a patient. In this example, the delivery device <NUM> is advanced through the trachea T and the bronchial tree BT to a location adjacent a peripheral node PN in the lung L of a patient. The medical needle assembly <NUM> is shown advanced through the delivery device <NUM>, and may be used to take a biopsy sample of the peripheral node. The delivery device <NUM> can be any suitable device configured for delivery of the needle assembly <NUM>. Some examples of suitable delivery devices may include an endoscope, a delivery sheath, a guide catheter, a delivery tube, or the like. In yet other embodiments, a delivery device may not be necessary, and the needle assembly <NUM> may be delivered and/or navigated directly though the anatomy of the patient.

<FIG> is a close-up cross-sectional side view of the distal portion of the delivery device <NUM> and the medical needle assembly <NUM> being advanced therein. As can be appreciated, the expandable distal portion <NUM> is in the second, expanded configuration as shown and described above with reference to <FIG>, in which the expandable distal portion <NUM> has an outer diameter D2 that is larger than the inner diameter D1 of the needle lumen <NUM>. In this configuration the sharp distal tip <NUM> may be considered to be radially protected and/or guarded by the expandable distal portion <NUM>. This may aid in navigating to a target or treatment site through a delivery device <NUM> such that the sharp distal tip <NUM> does not undesirably skive, scrape, puncture or become embedded or stuck in the delivery device <NUM>.

As shown in <FIG>, once the medical needle assembly <NUM> is navigated as desired to close proximity to a target and/or treatment cite, the expandable distal portion <NUM> may be shifted from the second, expanded configuration to the first, non-expanded configuration, as shown and described above with reference to <FIG> and <FIG>. As described above, in the first configuration, the expandable distal portion <NUM> has an outer diameter D2 that is the same as or less than the inner diameter D1 of the needle lumen <NUM>. In this first configuration, the sharp distal tip <NUM> may be considered to not be radially protected and/or guarded by the expandable distal portion <NUM>, relative to when in the second expanded configuration. Additionally, in this first configuration, the needle <NUM>, including the sharp distal tip <NUM>, may be longitudinally moved over and/or about and/or distally beyond the expandable distal portion <NUM>.

For example, <FIG> shows the needle <NUM> being advanced distally over the expandable distal portion <NUM> (which is in the first, non-expanded configuration) such that the sharp distal tip <NUM> is distal of the expandable distal portion <NUM> and is exposed for use, for example, in taking a biopsy sample.

<FIG> then shows the sharp distal tip <NUM> being advanced into tissue to obtain a biopsy sample. In <FIG>, the entire expandable medical device, including the elongated tubular member <NUM> (which includes the proximal body portion <NUM> and the expandable distal portion <NUM>) and the elongated inner member <NUM>, have been removed from the needle <NUM>, for example, by withdrawing them proximally through the needle <NUM>. After the needle <NUM> has been used to obtain a biopsy sample, the needle <NUM> (including the tissue sample) and delivery device <NUM> may be removed from the anatomy.

<FIG> show some additional example embodiments of needle assemblies and/or expandable medical devices in accordance with this disclosure that may be the same or similar in form and function to the needle assembly <NUM> and/or the expandable medical device described above. These example needle assemblies and/or expandable medical devices each include an elongated tubular member configured to be at least partially disposed within the needle lumen. Each of the elongated tubular members include a proximal body portion and an expandable distal portion, which is configured to shift between a first, radially non-expanded configuration and a second, radially expanded configuration, for example, through the use of an elongated inner member. The structures shown, named and numbered similarly in these embodiments may include structure, materials, and/or usage that are the same as or similar to those of any such similarly named and numbered structures shown and described herein, for example, in the embodiment above. Features, structures, materials, and usage of the various embodiments may be combined and/or used in other embodiments. For example, the discussion of the structure, materials, usage, form and/or function of the needle assembly and/or the expandable medical device and/or needle, and/or elongated tubular member and/or expandable distal portion and/or proximal body portion and/or elongated inner member and/or any of the features, parts or components thereof and any related structures in the embodiment above with reference to <FIG> may apply equally to any and all of the other embodiments described herein, and vice versa. In particular, the expandable distal portion and the elongated inner member in each of these embodiments, while possibly including some structural differences as noted, may still allow for shifting between a first, radially non-expanded configuration and a second, radially expanded configuration, and may be used for protecting the sharp distal tip of a needle in a similar manner and in accordance with the methods as described herein.

<FIG> shows a partial cross-sectional view of another example embodiment of a needle assembly <NUM> similar in form and function to needle assembly <NUM> shown and described with reference to <FIG> and <FIG>, wherein similarly named structures and/or similarly numbered structures may be similar in form and function as those discussed elsewhere herein. In this embodiment, however, elongated tubular member <NUM> includes an expandable distal portion <NUM> that may vary in wall thickness along at least a portion of its length. In the particular embodiment shown, the expandable distal portion <NUM> includes a tapered coil structure, wherein the diameter of the coil windings decreases as the windings extend distally. However, other embodiments may not include a coil, but some other tubular structure that may be tapered distally. Such a configuration may provide the expandable distal portion <NUM> with a tapered stiffness profile as it extends distally, with the more proximal portion including the larger wall thickness being stiffer, and the more distal portion including the smaller wall thickness being less stiff.

The expandable distal portion <NUM> has an inner surface <NUM> defining an inner lumen <NUM>, and an outer surface <NUM>. The expandable distal portion <NUM> has a wall <NUM> having a wall thickness that is defined between the inner surface <NUM> and the outer surface <NUM>. As may be appreciated, due to the tapered structure, the wall thickness may vary and/or taper along the length of the expandable distal portion <NUM>, with the wall thickness being greatest near the proximal end, and the least near the distal end. The expandable distal portion <NUM> may have an outer diameter D2 and an inner diameter D3. Similar to and/or because of the wall thickness taper, the inner diameter D3, the outer dimeter D2, or both, may also taper along the length expandable distal portion <NUM>.

Similar to the other embodiments described herein, the expandable distal portion <NUM> is designed to shift between a first, radially non-expanded configuration, and a second, radially expanded configuration. <FIG> shows the expandable distal portion <NUM> in the first configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is the same as or less than the inner diameter D1 of the needle lumen <NUM>. As such, in this first configuration, the needle <NUM>, including the sharp distal tip <NUM>, may be longitudinally moved over and/or about the expandable distal portion <NUM>, and/or the expandable distal portion <NUM> may be moved within the needle <NUM> such that it is disposed within and/or movable within the needle lumen <NUM>. In this first configuration, the sharp needle tip <NUM> may be considered to not be radially protected and/or guarded by the expandable distal portion <NUM>, relative to when in the second expanded configuration.

<FIG> shows the expandable distal portion <NUM> in the second configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is larger than the inner diameter D1 of the needle lumen <NUM>. At least a portion, such as the proximal portion, of the expandable distal portion <NUM> has an outer diameter D2 that is larger than the inner diameter D1 of the needle lumen <NUM>. The elongated inner member <NUM> has been moved longitudinally in a distal direction and forced into the inner lumen <NUM> of the expandable distal portion <NUM> with a predetermined amount of force, such that the outer surface <NUM> of the elongated inner member <NUM> engages and/or is engaged with the inner surface <NUM> of the expandable distal portion <NUM>. Because the outer diameter D6 of the elongated inner member <NUM> is larger than the initial (e.g. non-expanded) inner diameter D3 of the expandable distal member <NUM>, as the elongated inner member <NUM> is inserted therein, it forces the expandable distal member <NUM> to expand radially. This radial expansion thus increases both the inner diameter D3 and outer diameter D2 of the expandable distal portion <NUM> when in the second configuration relative to these diameters in the first configuration. As such, the expandable distal portion <NUM> when in this second configuration may have an outer diameter D2 that is configured such that it cannot fit within and/or be longitudinally movable within the needle lumen <NUM>. The expandable distal portion <NUM> is disposed adjacent to the sharp distal tip <NUM>, and now has a larger diameter D2, and thus may act to guard and/or protect the sharp distal tip <NUM>. As such, in this configuration, the sharp distal tip <NUM> may be considered to be radially protected and/or guarded by the expandable distal portion <NUM>.

<FIG> shows partial cross-sectional view of another example embodiment of a needle assembly <NUM> similar in form and function to needle assemblies <NUM> and <NUM> shown and described herein, wherein similarly named structures and/or similarly numbered structures may be similar in form and function as those discussed elsewhere herein. In this embodiment, however, the expandable distal portion <NUM> may be a non-coiled tubular member. Additionally, the entire elongated tubular member <NUM> may be of monolithic and/or unitary construction. In other words, the elongated tubular member <NUM>, including the proximal body portion <NUM> and the expandable distal portion <NUM>, may be a full length singular and/or monolithic structure, such as a tubular member, extrusion, coil, braid, mesh, or the like. In this particular embodiment shown, the elongated tubular member <NUM> may be a monolithic and/or singular tubular member and/or extrusion.

The expandable distal portion <NUM> has an inner surface <NUM> defining an inner lumen <NUM>, and an outer surface <NUM>. The expandable distal portion <NUM> has a wall <NUM> having a wall thickness that is defined between the inner surface <NUM> and the outer surface <NUM>. The wall thickness of the expandable distal portion <NUM> is greater than the wall thickness of the proximal body portion <NUM>. The expandable distal portion <NUM> may have an outer diameter D2 and an inner diameter D3. The expandable distal portion <NUM> may be configured to radially expand and/or contract such that it can shift between a first, radially non-expanded configuration and a second, radially expanded configuration, as will be discussed in more detail below and herein.

<FIG> shows side view of the needle assembly <NUM>. In the side view, it can be seen that the expandable distal portion <NUM> may include one or more expansion relief structures <NUM>, such as one or more channels, slots, folds, cuts, material changes, durometer changes, or the like, formed, cut, built and/or otherwise disposed in and extending longitudinally along and/or in the wall <NUM>. Such expansion relief structures <NUM> may allow for controlled and/or easier expansion of the monolithic and/or unitary expandable distal portion <NUM>. For example, the expansion relief structures <NUM> may be designed and/or configured to preferentially expand and/or be more expandable than the remaining portions of the wall <NUM>. The expandable distal portion <NUM> may include a single expansion relief structure <NUM> or may include a plurality of such expansion relief structures <NUM>. If a plurality of expansion relief structures are used, they may be spaced apart radially from each other in any fashion as desired. For example, a plurality of expansion relief structures <NUM> may be spaced apart radially equally about the expandable distal portion <NUM> (e.g., two expansion relief structures spaced radially apart by <NUM> degrees, three expansion relief structures spaced radially apart by <NUM> degrees, four expansion relief structures spaced radially apart by <NUM> degrees, etc.), or may be spaced apart unequally radially about the expandable distal portion <NUM> (e.g. three expansion relief structures, with a first two spaced radially apart from each other by <NUM> degrees, and a third spaced apart from the first two by <NUM>, etc.).

Similar to the other embodiments described herein, the expandable distal portion <NUM> is designed to shift between a first, radially non-expanded configuration, and a second, radially expanded configuration. <FIG> an <NUM> show the expandable distal portion <NUM> in the first, non-expanded configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is the same as or less than the inner diameter D1 of the needle lumen <NUM>. (as seen in <FIG>). As such, in this first configuration, the needle <NUM>, including the sharp distal tip <NUM>, may be longitudinally moved over and/or about the expandable distal portion <NUM>, and/or the expandable distal portion <NUM> may be moved within the needle <NUM> such that it is disposed within and/or movable within the needle lumen <NUM>. In this first configuration, the sharp needle tip <NUM> may be considered to not be radially protected and/or guarded by the expandable distal portion <NUM>, relative to when in the second expanded configuration.

In this particular embodiment, when in the first, non-expanded configuration, the elongated tubular member <NUM> may have a constant outer diameter along its length. For example, the outer diameter D2 of the expandable distal portion <NUM> may be equal to the outer diameter D5 the proximal body portion <NUM>. Additionally, in this embodiment, when in the first, non-expanded configuration, the inner diameter of the elongated tubular member <NUM> may vary along its length. For example, the inner diameter D3 of the expandable distal portion <NUM> may be smaller than the inner diameter D4 of the proximal body portion <NUM>. There may be a tapered transition in inner diameter and/or wall thickness of the elongated tubular member <NUM> between the proximal body portion <NUM> and the expandable distal portion <NUM>.

<FIG> shows the expandable distal portion <NUM> in the second configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is larger than the inner diameter D1 of the needle lumen <NUM>. The elongated inner member <NUM> has been moved longitudinally in a distal direction and forced into the inner lumen <NUM> of the expandable distal portion <NUM> with a predetermined amount of force, such that the outer surface <NUM> of the elongated inner member <NUM> engages and/or is engaged with the inner surface <NUM> of the expandable distal portion <NUM>. Because the outer diameter D6 of the elongated inner member <NUM> is larger than the initial (e.g. non-expanded) inner diameter D3 of the expandable distal member <NUM>, as the elongated inner member <NUM> is inserted therein, it forces the expandable distal portion <NUM> to expand radially. <FIG> shows a side view of the needle assembly <NUM> in the second, expanded configuration. As can be appreciated, the one or more expansion relief structures <NUM> may expand and/or open in response to the expansion force, allowing for better and/or more controlled and/or easier expansion of the monolithic and/or unitary expandable distal portion <NUM>. The expansion relief structures <NUM> may be designed and/or configured to preferentially expand and/or be more expandable than the remaining portions of the wall <NUM>.

Referring back to <FIG>, this radial expansion thus increases both the inner diameter D3 and outer diameter D2 of the expandable distal portion <NUM> when in the second configuration relative to these diameters in the first, non-expanded configuration. As such, the expandable distal portion <NUM> when in this second, expanded configuration may have an outer diameter D2 that is configured such that it cannot fit within and/or be longitudinally movable within the needle lumen <NUM>. The expandable distal portion <NUM> is disposed adjacent to the sharp distal tip <NUM>, and now has a larger diameter D2, and thus may act to guard and/or protect the sharp distal tip <NUM>. As such, in this configuration, the sharp distal tip <NUM> may be considered to be radially protected and/or guarded by the expandable distal portion <NUM>.

<FIG> shows partial cross-sectional view of another example embodiment of a needle assembly <NUM> similar in form and function to needle assemblies <NUM>, <NUM> and <NUM> shown and described herein, wherein similarly named structures and/or similarly numbered structures may be similar in form and function to those discussed elsewhere herein. In this embodiment, the elongated tubular member <NUM> may include a constant wall thickness along its length. The elongated tubular member <NUM> includes the proximal body portion <NUM> and the expandable distal portion <NUM>. The proximal body portion <NUM> has an outer surface <NUM> and an inner surface <NUM>, which defines an inner lumen <NUM>. The proximal body portion <NUM> has a wall <NUM> having a first wall thickness which is defined between the outer surface <NUM> and the inner surface <NUM>. The expandable distal portion <NUM> has an inner surface <NUM> defining an inner lumen <NUM>, and an outer surface <NUM>. The expandable distal portion <NUM> has a wall <NUM> having a wall thickness that is defined between the inner surface <NUM> and the outer surface <NUM>. The wall thickness of the expandable distal portion <NUM> is the same as the wall thickness of the proximal body portion <NUM>. As in other embodiments herein, the expandable distal portion <NUM> may be configured to radially expand and/or contract such that it can shift between a first, radially non-expanded configuration and a second, radially expanded configuration. The proximal body portion <NUM> may have an outer diameter D5 and an inner diameter D4. The expandable distal portion <NUM> may have an outer diameter D2 and an inner diameter D3. As can be appreciated, because of the constant wall thickness along the length of the elongated tubular member <NUM>, when the expandable distal portion <NUM> is in the first, non-expanded configuration, the outer diameter D2 may equal to the outer diameter D5, and the inner diameter D3 may equal the inner diameter D4.

The elongated inner member <NUM> in this embodiment includes different and/or varying outer diameters along its length. The elongated inner member <NUM> includes a proximal segment <NUM> and a distal segment <NUM>. The proximal segment <NUM> has an outer surface <NUM> and an outer diameter D6, and the distal segment <NUM> has an outer surface <NUM> and an outer diameter D7 that is greater than the outer diameter D6 of proximal segment <NUM>. The outer diameter D6 of the proximal segment <NUM> may be sized and/or configured such that the proximal segment <NUM> of the elongated inner member <NUM> may fit within, and/or be longitudinally movable within, the elongated tubular member <NUM>. For example, the proximal segment <NUM> of the elongated inner member <NUM> may be sized and/or configured to fit within and/or be longitudinally movable within the inner lumen <NUM> of the proximal body portion <NUM> and the inner lumen <NUM> of the expandable distal portion <NUM>. For example, the elongated inner member <NUM> may have an outer diameter D6 that is less than the inner diameter D4 of the proximal body portion <NUM> and less than the inner diameter D3 of the distal expandable portion <NUM>, such that the proximal segment <NUM> of the elongated inner member <NUM> may be disposed within and/or longitudinally movable within the inner lumens <NUM> and <NUM>. The outer diameter D7 of the distal segment <NUM>, however, may be greater than the inner diameter D3 of the expandable distal portion <NUM>, and may also be greater than the inner diameter D4 of the proximal body portion <NUM>.

As shown in <FIG>, the elongated inner member <NUM> may be at least partially disposed within the elongated tubular member <NUM> such that the proximal segment <NUM> is disposed within the inner lumens <NUM> and <NUM>, and the distal segment <NUM> extends distally beyond the expandable distal portion <NUM>. The elongated inner member <NUM> may be configured and/or arranged to shift the expandable distal portion <NUM> between the first, or radially non-expanded configuration and the second, or radially expanded configuration. For example, distal segment <NUM> including the outer diameter D7 that is larger than the inner diameter D3 of the expandable distal portion <NUM> when in the first, or radially non-expanded configuration may be used to expand the expandable distal portion <NUM>.

<FIG> shows the expandable distal portion <NUM> in the first, non-expanded configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is the same as or less than the inner diameter D1 of the needle lumen <NUM>. As such, in this first configuration, the needle <NUM>, including the sharp distal tip <NUM>, may be longitudinally moved over and/or about the expandable distal portion <NUM>, and/or the expandable distal portion <NUM> may be moved within the needle <NUM> such that it is disposed within and/or movable within the needle lumen <NUM>. Similarly, the outer diameter D7 of the distal segment <NUM> of the elongated inner member <NUM> may be less than the inner diameter D1 of the needle lumen <NUM>. As such, the needle <NUM> may similarly be longitudinally moved over and/or about the distal segment <NUM> of the elongated inner member <NUM>, and/or the distal segment <NUM> of the elongated inner member <NUM> may be moved within the needle <NUM> such that it is disposed within and/or movable within the needle lumen <NUM>. In this first configuration, the sharp needle tip <NUM> may be considered to not be radially protected and/or guarded by the expandable distal portion <NUM>, relative to when in the second expanded configuration.

<FIG> shows the expandable distal portion <NUM> in the second configuration, in which the expandable distal portion <NUM> has an outer diameter D2 that is larger than the inner diameter D1 of the needle lumen <NUM>. The elongated inner member <NUM> has been moved longitudinally in a proximal direction and forced into the inner lumen <NUM> of the expandable distal portion <NUM> with a predetermined amount of force, such that the outer surface <NUM> of the distal portion <NUM> of the elongated inner member <NUM> engages and/or is engaged with the inner surface <NUM> of the expandable distal portion <NUM>. Because the outer diameter D7 of the elongated inner member <NUM> is larger than the initial (e.g. non-expanded) inner diameter D3 of the expandable distal member <NUM>, as the elongated inner member <NUM> is inserted therein, it forces the expandable distal portion <NUM> to expand radially. As can be appreciated, the expandable distal member <NUM> may include one or more expansion relief structures, as discussed elsewhere herein, that may expand and/or open in response to the expansion force, allowing for better and/or more controlled and/or easier expansion of the expandable distal portion <NUM>. Additionally or alternatively, the expandable distal member <NUM> may include structure and/or materials that allow it to expand.

This radial expansion thus increases both the inner diameter D3 and outer diameter D2 of the expandable distal portion <NUM> when in the second configuration relative to these diameters in the first, non-expanded configuration. As such, the expandable distal portion <NUM> when in this second, expanded configuration may have an outer diameter D2 that is configured such that it cannot fit within and/or be longitudinally movable within the needle lumen <NUM>. The expandable distal portion <NUM> is disposed adjacent to the sharp distal tip <NUM>, and now has a larger diameter D2, and thus may act to guard and/or protect the sharp distal tip <NUM>. As such, in this configuration, the sharp distal tip <NUM> may be considered to be radially protected and/or guarded by the expandable distal portion <NUM>.

<FIG> shows partial cross-sectional view of an alternative example configuration for a medical needle assembly <NUM>. Similar to the embodiments above, the medical needle assembly <NUM> includes a needle <NUM> having a needle body <NUM> defining a sharp distal tip <NUM>. The needle body <NUM> has an outer surface <NUM>, an inner surface <NUM>, and defines a needle lumen <NUM> having an inner diameter. The sharp distal tip <NUM> defines a distal needle opening <NUM> into the needle lumen <NUM>. The needle <NUM> may be of any of a wide variety of medical needles, for example, any of those already discussed herein.

In this embodiment, the needle assembly <NUM> includes an elongated stylet <NUM>. The stylet includes a proximal segment <NUM>, a distal segment <NUM>, and an intermediate segment <NUM> disposed between the proximal and distal segments. The distal segment <NUM> includes a rounded blunt tip <NUM>.

The stylet <NUM> may include a stiffness profile that varies along at least a portion of the length of the stylet <NUM>. For example, the distal segment <NUM> includes an elongated tapering profile, wherein the diameter of the distal segment <NUM> decreases as it extends distally. As such, the distal segment <NUM> may be less stiff (e.g. more flexible) adjacent the tip <NUM>, and gradually becomes stiffer (e.g. less flexible) as it extends proximally, with the stiffest portion disposed adjacent the intermediate segment <NUM>. The intermediate segment <NUM> may be stiffer (e.g. less flexible) than the distal segment <NUM>, for example, due to its larger diameter. The proximal segment <NUM> may also be stiffer (e.g. less flexible) than the distal segment <NUM>, for example, due to its larger diameter. The proximal segment <NUM> and the intermediate segment <NUM> may be generally the same stiffness, for example, due to their common diameter. Additionally, or alternatively, the stylet <NUM> may include the use of different materials, such as different metals or polymers, with differing stiffness or durometers along the length thereof to achieve stiffness profile variations. For example, intermediate segment <NUM> may include a metal or polymer with higher stiffness or durometer, while the distal segment <NUM> may include a metal or polymer with lower stiffness or durometer. Similarly, the proximal segment <NUM> may include a metal or polymer with higher stiffness or durometer relative to the material used in the distal segment <NUM>. The proximal segment <NUM> and the intermediate segment <NUM> may be generally the same stiffness through the use of similar stiffness materials, or may vary in stiffness from one another, for example, through the use of materials with varying stiffness. In some embodiments, the proximal segment <NUM> may be stiffer than the intermediate segment <NUM>, while in other embodiments, the proximal segment <NUM> may be less stiff than the intermediate segment <NUM>, or they may be the same stiffness, as desired.

Furthermore, as shown in <FIG>, the tapered distal segment <NUM> may extend distally beyond the intermediate segment for a significant length. This long length distal segment <NUM> provides for a longer taper, and a more gradual variation in the stiffness profile. Additionally, this long distal segment <NUM> may aid in navigation and/or in helping to guard or protect the sharp needle tip <NUM> from undesirably contacting a delivery device and/or anatomy during navigation, as discussed in more detail below. In some embodiments, the tapered distal segment <NUM> has a length in the range of about <NUM> to about <NUM>.

As may also be appreciated, there is a tight tolerance between the outer surface <NUM> of stylet and the inner surface <NUM> of the needle <NUM>. There is very little or no gap between the inner surface <NUM> of the needle <NUM> and the outer surface <NUM> of stylet.

The stylet <NUM> is disposed within the needle <NUM> such that the rigid intermediate segment <NUM> is disposed under and/or within the sharp distal tip <NUM> of the needle <NUM>, and the tapered distal segment <NUM> extends distally beyond the sharp distal tip <NUM> and the rigid intermediate segment <NUM>. In other words, the sharp distal tip <NUM> of the needle is disposed about and/or around the rigid intermediate segment <NUM>, and/or surrounds the rigid intermediate segment <NUM>. As such, the rigid intermediate segment <NUM> rigidly supports the sharp distal tip <NUM> of the needle, and thus reduces the likelihood that needle will flex and/or bend away from the stylet <NUM> when force is applied, for example, during navigation. As such, it is less likely that a gap would be created between the stylet <NUM> and the sharp distal tip <NUM>, and therefore less likely that the sharp need tip <NUM> would undesirably skive, scrape, puncture or become embedded or stuck in the delivery device or in the anatomy during navigation.

Additionally, the long distal segment <NUM> may aid in navigation and/or in helping to guard or protect the sharp needle tip from undesirably contacting a delivery device and/or the anatomy during such navigation. Because of the long length of the tapered distal segment <NUM>, the blunt tip <NUM> is spaced a significant distance distally from the sharp need tip <NUM>. During navigation, especially though tight and/or tortuous curves, the blunt tip <NUM> will be leading, and will generally be the first structure of the assembly <NUM> to make contact with the delivery device and/or antomy. The long tapered distal segment <NUM> may help to space the sharp need tip <NUM> from this contact with the delivery device and/or tissue and may help to dissipate any bending force applied to the stylet <NUM>. For example, the long distal segment <NUM> having a tapered stiffness may guide the needle during navigation, for example, through tight curves. As such, the long tapered distal segment <NUM>, in conjunction with the rigid intermediate segment <NUM>, may help to reduce and/or prevent separation of the needle <NUM> from the stylet <NUM>, thus making it less likely that a gap would be created between the stylet <NUM> and the sharp needle tip <NUM>, and therefore less likely that the sharp needle tip <NUM> would undesirably skive, scrape, puncture or become embedded or stuck in the delivery device or in the anatomy during navigation.

The materials that can be used for the various devices, assemblies and components disclosed herein may include those commonly associated with medical devices. For example, the needle, expandable medical device, elongated tubular member, expandable distal portion, proximal body portion, elongated inner member, stylet, and/or any of the components thereof or of any of medical needle assemblies disclosed herein may be made from a metal, metal alloy, polymer, a metal-polymer composite, ceramics, combinations thereof, and the like, or other suitable material or composites of materials. Some examples of suitable metals and metal alloys include stainless steel, such as 304V, <NUM>, 316LV, and <NUM>-<NUM> stainless steel; mild steel; nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol; other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL® <NUM>, UNS: N06022 such as HASTELLOY® C-<NUM>®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® <NUM>, NICKELVAC® <NUM>, NICORROS® <NUM>, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like); platinum enriched stainless steel; titanium; combinations thereof; and the like; or any other suitable material.

Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, for example, DELRIN® available from DuPont), polyether block ester, polyurethane (for example, Polyurethane 85A), thermoplastic polyurethane (for example, PELLETHANE®), polypropylene (PP), polyvinylchloride (PVC), polyetherester (for example, ARNITEL® available from DSM Engineering Plastics), ether or ester based copolymers (for example, butylene/poly(alkylene ether) phthalate and/or other polyester elastomers such as HYTREL® available from DuPont), polyamide (for example, DURETHAN® available from Bayer or CRISTAMID® available from Elf Atochem), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE), Marlex high-density polyethylene, Marlex low-density polyethylene, linear low density polyethylene (for example REXELL®), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly paraphenylene terephthalamide (for example, KEVLAR®), polysulfone, nylon, nylon-<NUM> (such as GRILAMID® available from EMS American Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS 50A), polycarbonates, ionomers, biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers thereof, polymer/metal composites, and the like. In some embodiments the sheath can be blended with a liquid crystal polymer (LCP). For example, the mixture can contain up to about <NUM> percent LCP.

The needle, expandable medical device, elongated tubular member, expandable distal portion, proximal body portion, elongated inner member, stylet, and/or any of the components thereof or of any of medical needle assemblies disclosed herein may include the use of different metals or polymers with differing stiffness or durometers along the length thereof. For example, a more proximal section of any of the components, devices or assemblies disclosed herein may include a metal or polymer with higher stiffness or durometer and a more distal section may include a metal or polymer with lower stiffness or durometer. Any of the components, devices or assemblies disclosed herein may include or be made of one or more layers of materials. For example, a plurality or layers of differing material may be used to form all or portions of the any of the components, devices or assemblies disclosed herein. Any of the components, devices or assemblies disclosed herein may also include and/or be entirely made of a reinforcement member, such as a braid, coil, mesh, or the like.

In at least some embodiments, portions or all of the needle, expandable medical device, elongated tubular member, expandable distal portion, proximal body portion, elongated inner member, stylet, and/or any of the components thereof or of any of medical needle assemblies disclosed herein may be doped with, made of, or otherwise include a radiopaque material. Radiopaque materials are understood to be materials capable of producing a relatively bright image on a fluoroscopy screen or another imaging technique during a medical procedure. This relatively bright image aids the user of the guide extension catheter in determining its location. Some examples of radiopaque materials can include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloy, polymer material loaded with a radiopaque filler, and the like. Additionally, other radiopaque marker bands and/or coils may also be incorporated into the design to achieve the same result.

Claim 1:
An expandable device for guarding a sharp distal tip (<NUM>) of a needle (<NUM>) defining a needle lumen (<NUM>) having an inner diameter (D1), the expandable device comprising:
an elongated tubular member (<NUM>) including a proximal body portion (<NUM>) configured to be at least partially disposed within the needle lumen (<NUM>) and an expandable distal portion (<NUM>) defining an inner lumen (<NUM>) including an inner surface (<NUM>), wherein the expandable distal portion (<NUM>) is designed to shift between a first configuration in which the expandable distal portion (<NUM>) has an outer diameter (D2) that is the same or less than the inner diameter (D1) of the needle lumen (<NUM>) and a second configuration in which the expandable distal portion (<NUM>) has an outer diameter (D2) that is greater than the inner diameter (D1) of the needle lumen (<NUM>) and is configured to guard the sharp distal tip (<NUM>) of the needle (<NUM>); and
an elongated inner member (<NUM>) configured to be at least partially disposed within the inner lumen (<NUM>) of the elongated tubular member (<NUM>) and being configured to shift the expandable distal portion (<NUM>) between the first configuration and the second configuration;
characterized in that the elongated inner member (<NUM>) defines an outer surface (<NUM>), wherein
the outer surface (<NUM>) of the elongated inner member (<NUM>) engages the inner surface (<NUM>) of the expandable distal portion (<NUM>) to shift the expandable distal portion (<NUM>) from the first configuration to the second configuration, and wherein the outer surface (<NUM>) of the elongate inner member (<NUM>) disengages from the inner surface (<NUM>) of the expandable distal portion (<NUM>) to shift the expandable distal portion (<NUM>) from the second configuration to the first configuration.