Selectable angle needle guide

A needle guide assembly for inserting a needle into the body of a patient in order to access a subcutaneous target, such as a vessel, is disclosed. In one embodiment, the needle guide assembly comprises a needle guide body that is configured to at least indirectly and removably attach to an image producing device, such as an ultrasound probe. The needle guide body defines at least first and second elongate guide channels. Each guide channel defines a unique insertion angle with respect to a longitudinal axis of the ultrasound probe. Further, each guide channel is configured to accept needles of differing gauges.

BRIEF SUMMARY

Briefly summarized, embodiments of the present invention are directed to a needle guide assembly for inserting a needle into the body of a patient in order to access a subcutaneous target, such as a vessel. In one embodiment, the needle guide assembly comprises a needle guide body that is configured to at least indirectly and removably attach to an image producing device, such as an ultrasound probe. The needle guide body defines at least first and second elongate guide channels. Each guide channel defines a unique insertion angle with respect to a longitudinal axis of the ultrasound probe. Further, each guide channel is configured to accept needles of differing gauges.

In addition, other needle guide assemblies are disclosed that include multiple guide channels for inserting a needle at a variety of insertion angles into the patient's body. Related methods are also disclosed.

These and other features of embodiments of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of embodiments of the invention as set forth hereinafter.

DETAILED DESCRIPTION OF SELECTED EMBODIMENTS

Reference will now be made to figures wherein like structures will be provided with like reference designations. It is understood that the drawings are diagrammatic and schematic representations of exemplary embodiments of the present invention, and are neither limiting nor necessarily drawn to scale. It is to be understood that the words “including,” “has,” and “having,” as used herein, including the claims, shall have the same meaning as the word “comprising.”

Embodiments of the present invention are generally directed to a needle guide assembly for guiding a needle or other elongate implement into a body of a patient. In one embodiment, the needle guide is removably attached in a direct or indirect manner to an ultrasound probe so as to enable insertion of the needle via the needle guide assembly while an intended subcutaneous target of the needle is being imaged by the ultrasound probe. Further, in one embodiment, the needle guide assembly includes multiple differently angled needle guide channels that are selectable by a user to enable the needle to be directed at a desired angle into the patient's body toward the subcutaneous target. Thus, the ability to direct a needle at a variety of angles with a single guide assembly is achieved.

FIGS. 1A-1Ddepict one example of a needle guide assembly, generally designated at10, according to one embodiment. As shown, the needle guide assembly10includes a body12for attaching the assembly to an image producing device, as will be described further below. In one embodiment, the image producing device includes a handheld probe of an ultrasound imaging device, though other imaging devices can also be utilized, such x-ray and MRI-based systems, for example. Optionally, the needle guide assembly can be attached to other components in addition to image producing devices. The needle guide body12in the present embodiment includes thermoplastic, but in other embodiments other materials can be employed, including other types of plastic, metals, metal alloys, ceramics, etc.

As shown in the perspective shown inFIGS. 1A and 1B, the needle guide body12in the present embodiment defines three front faces22A,22B, and22C. At the bottom of each of the front faces22A-22C, a corresponding guide channel20A,20B, and20C is defined. Each guide channel20A-20C defines a unique angle of attack, or needle insertion angle, for a needle disposed therein. Correspondingly, each front face22A-22C is oriented so as to be disposed at substantially a right angle with the longitudinal length of the respective guide channel20A-20C, as best seen inFIG. 1C. As will be seen further below, the unique angling of each guide channel facilitates proper placement of a needle into a patient so as to access a desired target at a particular subcutaneous depth, such as a vessel, for instance.

Each of the front faces22A-22C includes a concavely shaped contoured surface24that slopes toward an open proximal end26A,26B,26C of the respective guide channel20A-20C. The contoured surfaces24assist in guiding a needle tip placed thereon toward the respective guide channel proximal end opening, thus easing needle insertion into the guide channel. It is appreciated that the front faces can be contoured in other ways as well.

Also, as best seen inFIG. 1D, the proximal ends26A-26C of the guide channels20A-20C extend slightly proximal to the respective front faces22A-22C so as to further ease insertion of the needle tip into the particular guide channel.

The needle guide assembly10in the present embodiment is configured so as to be movable with respect to the ultrasound probe or other device with which it is connected.FIGS. 1A and 1Cshow one implementation of this, wherein the needle guide body12includes a track30configured to slidably engage a rail60(FIGS. 4 and 5) associated with the probe, thus enabling the needle guide body to slide with respect to the probe, as will be further discussed below. As shown, the track30includes an L-shaped configuration to assist the needle guide in remaining physically engaged with the rail60. Note that this is but one example of fixtures to provide connection between the probe and the needle guide; indeed, various other connection schemes can be employed. In addition, it is appreciated that the needle guide can be indirectly or indirectly and temporarily or permanently attached to other surfaces of the ultrasound probe, including side surfaces, end surfaces, etc.

FIG. 2shows a proximal end view of the guide channel20B, which is representative of the other guide channels20A and20C, and thus the description here equally applies to each guide channel. As shown, the guide channel20B includes two arms40that each extend distally from the proximal end26B along the length of the needle guide body12to enclose an elongate volume into which a portion of the needle is disposed when the needle is inserted into the guide channel20B. Cross sectionally, the arms40are shaped to extend from the needle guide body12and terminate toward each other such that an opening42is defined between the terminal arm ends. The opening42runs the entire length between the arms40so as to define a slot through which a needle or other suitable elongate device can be removed from the guide channel20A-20C when desired. Notches44are also included in each arm40proximate attachment of the arm with the main portion of the needle guide body12. The shape of the arms40, together with the notches44, enables the guide channel20B to expand when needed to receive therewithin needles of a variety of gauges. This in turn offers flexibility for the needle guide10and enables it to be used to guide a variety of needles into the patient while still maintaining a suitable amount of directional constraint for the needle such that it enters the patient's body at the intended needle insertion angle. The notches44are particularly suited to facilitating expansion of the channel size while maintaining suitable amounts of force imposed on the needle by the arms40, resulting in the above-mentioned constraint. Note that in one embodiment at least the arms40include a thermoplastic or other suitably compliant material to enable bending thereof, as just described.

It is appreciated that the number, size, shape, placement, etc. of the guide channels on the needle guide can vary from what is shown and described herein. Further, though all are similarly configured in the embodiment ofFIGS. 1A-1D, it is appreciated that the particular configuration of the guide channels can vary one from another on the same needle guide. Thus, these and other expansions of the principles discussed herein are contemplated.

FIG. 3shows the needle guide assembly10disposed in a storage tray52together with a probe cap54. An ultrasound probe50is shown with a head thereof removably inserted into the probe cap54, in preparation for removing the probe cap and the needle guide assembly10from the tray52. As such, it is appreciated that in the present embodiment the tray52is an example of a manner in which the needle guide assembly can be packaged, sterilized, and stored prior to use by a clinician, though other packaging configurations are also contemplated.

FIG. 4shows the manner of attachment of a head portion56of the ultrasound probe50with the probe cap54.FIGS. 4 and 5show details of the rail60that extends from the probe cap54and serves as a fixture for attachment of the needle guide assembly10thereto. Note that, though a probe cap is used here for attachment, in other embodiments the needle guide assembly can be attached directly to the probe itself, or directly/indirectly to another device. Further details regarding probe caps with which the needle guide assembly described herein can be used can be found in U.S. Patent Publication No. 2011/0313293, filed Aug. 9, 2011, and entitled “Support and Cover Structures for an Ultrasound Probe Head,” which is incorporated herein by reference in its entirety.

As shown, the rail60includes an L-shaped cross sectional shape to match the shape of the track30and to assist in maintaining engagement with the needle guide assembly10, though it is appreciated that other rail shapes can also be employed.FIG. 6shows the rail60of the probe cap54slidably inserted into the track30defined by the needle guide assembly10such that needle guide assembly is in position for use in guiding a needle into the body of a patient. Note that the probe50includes an arrow66that indicates the lateral center of the device, for alignment purposes during use. As best seen inFIG. 4, a notch64is included on the rail60that is aligned with the probe arrow66when the probe cap54is properly attached the probe50, and can be used to assist the clinician in aligning a needle with the center of the probe head56when no needle guide is used.

FIG. 5shows that a plurality of detents62are included on the rail60. The detents62are spaced so as to individually engage with a nub34, disposed in the track30(FIG. 1C) when a respective one of the guide channels20A-20C are aligned with the arrow66of the probe50, i.e., in position to guide a needle into the body of the patient.

With the needle guide assembly10attached to the probe cap54of the probe50via the track30and rail60engagement described above and as shown inFIG. 6, the needle guide assembly can be employed to guide a needle into the body of a patient. As mentioned and as seen inFIG. 6, each guide channel20A-20C defines a unique needle insertion angle with respect to a longitudinal axis of the probe50(or, optionally, the skin surface of the patient when the cap-covered probe head56is positioned against the skin in the orientation shown inFIG. 6). The front faces22A-22C of the needle guide body12inFIG. 6are marked with a depth number indicating the depth at which a needle inserted through the corresponding guide channel20A-20C would intercept the plane of the image produced by the ultrasound probe.

Thus, in the configuration shown inFIG. 6, the guide channel20B is aligned with the probe arrow66such that a needle70that is passed therethrough enters the center of the image produced by the probe50. As indicated on its front face22B, the needle insertion angle of the guide channel20B is such that the needle70will intercept the image plane of the probe50approximately 0.5 cm below the surface of the skin.

Thus, during an ultrasound imaging procedure, a clinician can observe an image produced by the ultrasound probe of an intended subcutaneous target, such as a vein, when the probe is placed against the skin of the patient. Once the target is imaged by the probe, the clinician can inspect the image and determine or observe the depth of the target under the skin. The clinician can then laterally slide the needle guide body along the probe rail60until the guide channel20A-20C that is marked with a depth corresponding to the depth of the target is aligned with the center of the probe, indicated by the arrow66on the probe head56. Note that the needle guide body12is maintained in the selected position via engagement of the nub34in the track30(FIG. 1C) with the corresponding detent62on the rail60(FIG. 5). In the configuration shown inFIG. 6, for example, the nub34is engaged with the middle detent62so as to maintain the guide channel20B aligned with the center of the probe50indicated by the arrow66. The needle70can then be inserted into the selected guide channel20A-20C (e.g., guide channel20B in the example shown inFIG. 6) and with continued use of the ultrasound image, the needle can be guided to the intended subcutaneous target.

If a deeper or shallower insertion angle is desired in order to access a deeper or shallower target, respectively, the needle guide assembly10can be laterally slid so that the guide channel having the desired target interception depth as marked on the front face22A-22C is centered with the probe arrow66. A needle or other suitable elongate instrument can then be inserted through the guide channel and into the patient's skin while the probe50is held in place against the skin to continue imaging the target. This is illustrated inFIG. 7, wherein the needle guide assembly10is positioned as described and the needle70is inserted through the guide channel20A so as to intercept the ultrasound imager plane at a depth under the skin of approximately 0.25 cm. Note the relatively more shallow needle insertion angle of the guide channel20A (as evidenced by the less steeply angled needle70) inFIG. 7in comparison with the needle insertion angle of the guide channel20B inFIG. 6.

As described above, each guide channel20A-20C includes a slot defined by the longitudinal opening42between the guide channel arms40(FIGS. 1B, 2). Once the target has been accessed, the needle70can be removed from engagement with the needle guide assembly10by gently pulling the assembly away from the needle such that the needle pulls through the slot of the guide channel20A-20C and separates from the needle guide assembly.

As was mentioned, the needle guide assembly10can include guide channels defining other needle insertion angles and corresponding image plane interception depths. One example of this is shown inFIG. 8, wherein the needle guide assembly body12defines needle guide channels20A,20B, and20C that include relatively steeper needle insertion angles than those of the assembly shown inFIGS. 1A-1D, which are useful for accessing relatively deeper subcutaneous targets within the body of the patient. Thus, it is appreciated that guide channels of a variety of needle insertion angles can be included on the needle guide. In addition, the needle guide assembly can define different numbers and positions of guide channels other than what is explicitly shown and described herein. Moreover, the various guide channels and/or front faces corresponding thereto can be color-coded to assist the user in selecting a desired insertion angle. It is also appreciated that, though disclosed herein as being able to accommodate needles of multiple gauges, the guide channels of the needle guide assemblies of other embodiments can be configured for accommodating needles of only a single gauge, if desired. These and other variations to the needle guide assembly are therefore contemplated.

FIGS. 9A-9Cdepict details of a needle guide assembly110, according to another embodiment, including a base112defining a cavity122for attaching the assembly to a corresponding fixture on an ultrasound probe or other suitable device, and a platform114. The platform114includes a plurality of differently angled guide channels120and is slidably attached to the base112so as to enable the platform to slide laterally with respect to the base.

In greater detail, the platform114is shaped such that each guide channel120defines a unique needle insertion angle for a needle disposed therein. As with the needle guide assembly ofFIGS. 1A-1D, the needle guide assembly110is slidably adjustable with respect to the ultrasound probe to enable the clinician to laterally slide the platform114of the assembly until the guide channel120that matches the required depth to the intended subcutaneous target as imaged by the probe is aligned with the center of the probe. The needle can then be inserted into the selected guide channel120and with continued use of the ultrasound imaging, the needle can be guided to the intended target. Note again that, as with the other embodiments herein, the number, shape, angle, and configuration of the needle guide channels can vary from what is shown and described. Note also that the needle guide assemblies herein can be configured to guide other elongate implements in addition to needles. Further, note that the needle guide assembly can be configured such that the guide channel to be used is positioned at some point other than at the lateral center of the ultrasound probe or other device to which the assembly is operably attached.

FIG. 9Bshows the dovetail-type engagement of the platform114with the base112to enable relative sliding therebetween. Nubs or other interference features can be included on the base112, the platform114, or both to enable each guide channel120to lock into place when positioned for use. The base112can be removable from the ultrasound probe/cap via a snap-fit engagement of the cavity112thereof with a suitable fixture on the probe, or permanently affixed thereto. Note that the design of the cavity and fixture can vary from what is shown and described herein, as may be appreciated. In other embodiments the platform can include a semi-circular, parabolic, elliptical, or other non-linear shape to enable the platform to arcuately or otherwise slide about the base. Note that the dovetail-type engagement between the platform and the base can be replaced by other engagement schemes that enable relative movement therebetween.

FIGS. 10A and 10Bdepict another example of a needle guide assembly210, which includes a base212and a stepped platform214. The platform214includes multiple needle guide channels220oriented at similar needle insertion angles but at differing distances from a needle insertion point on the skin of the patient when the needle guide assembly210is attached to an ultrasound probe. The differing distances of the guide channels220from the needle insertion site on the skin (caused by the stepped platform214) enables each guide channel to guide a needle to a unique depth of intersection with the image plane of the ultrasound probe, and thus to targets at different subcutaneous depths. Thus, a clinician can select a desired one of the needle guide channels220that corresponds to the ultrasonically imaged depth of the subcutaneous target. In one embodiment, the clinician slides the ultrasound probe laterally to align the selected needle guide channel220with the imaged target as the needle guide assembly is not slidable in the design shown inFIGS. 10A and 10B, though the needle guide can be made movable in other embodiments. Note again that the number and indicated angles of the needle guide assembly210as illustrated in the accompanying figures are only examples and other configurations are, of course, possible. In another embodiment, it is appreciated that the guide channels define differing needle insertion angles independent of their separation via the stepped platform. In yet another embodiment, the guide channels are not parallel to one another, but are disposed on the platform so as to converge toward one another.

FIGS. 11A and 11Bshow a needle guide assembly310according to another embodiment, including a body312defining a cavity322for attachment to a probe, probe cap, or the like. A platform314including a slotted needle guide channel320is also included. In particular, the platform314includes a notched arm316that is slidably disposed between two arcuate rails318of the body312. So configured, the platform314is slidable along the rails318to enable the insertion angle of the guide channel320to be modified as desired by the user so as to enable a needle inserted therein to intercept an imaged subcutaneous target, such as a vessel. In one embodiment, the insertion angle with respect to the skin of the patient can vary from about a few degrees to about 90 degrees or more. Note that depth markers can be included on the rails318or other portion of the needle guide assembly310. Note further that in one embodiment the platform can be configured to be releasably lockable to the rails so as to maintain the needle guide channel at a desired angle.

FIGS. 12A and 12Bshow the manner of releasable engagement of the needle guide assembly310with a fixture332of a probe cap330, according to one possible mounting scheme. Of course, other direct or indirect engagement schemes of the probe/probe cap with this or the other needle guide assemblies disclosed herein can be employed.

Embodiments of the invention may be embodied in other specific forms without departing from the spirit of the present disclosure. The described embodiments are to be considered in all respects only as illustrative, not restrictive. The scope of the embodiments is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.