Patent Description:
Further <CIT>discloses an implantable patient access port which provides a subcutaneous route for access using an external filament such as an internal catheter, needle, wire or optical fiber.

Moreover, <CIT> discloses an infusion port designed for the introduction of a catheter for fluid infusion or removal or other flexible filaments within a patient. The infusion port is buried subcutaneously and accessed using a needle which introduces the filament.

The present invention is directed to the low-profile access port of claim <NUM>, and the method for manufacturing a low-profile access port for subcutaneous placement in a patient according to claim <NUM>. The dependent claims refer to preferred embodiments. Briefly summarized, embodiments of the present invention are directed to a low- profile access port for subcutaneous implantation within the body of a patient. The access port includes a receiving cup that provides a relatively large subcutaneous target to enable a catheter-bearing needle to access the port without difficulty. In addition, the access port includes a valve/seal assembly to permit pressurized fluid injection through the port while preventing backflow.

In one embodiment, therefore, a low-profile access port comprises a body including a conduit with an inlet port at a proximal end thereof, and a receiving cup. The receiving cup is concavely shaped to direct a catheter-bearing needle into the conduit via the inlet port. The receiving cup is oriented substantially toward a skin surface when subcutaneously implanted within the patient to ease needle impingement thereon. A valve/seal assembly disposed in the conduit enables passage of the catheter therethrough while preventing fluid backflow.

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.

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.

For clarity it is to be understood that the word "proximal" refers to a direction relatively closer to a clinician using the device to be described herein, while the word "distal" refers to a direction relatively further from the clinician. For example, the end of a catheter placed within the body of a patient is considered a distal end of the catheter, while the catheter end remaining outside the body is a proximal end of the catheter. Also, 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 an access port for subcutaneous implantation within the body of a patient. The implanted access port is transcutaneously accessible by a catheter-bearing needle, such as a peripheral intravenous ("PIV") catheter, so as to place the PIV catheter into fluid communication with the access port. A fluid outlet of the access port is operably connected to an in-dwelling catheter disposed within the vasculature of a patient, in one embodiment, to enable the infusion into and/or removal of fluids from the patient's vasculature to take place via the PIV catheter,.

In accordance with one embodiment, the access port defines a low profile so as to facilitate ease of placement within the subcutaneous tissue of the patient. Further, the access port is configured to provide a relatively large subcutaneous target to enable the PIV catheter or other suitable catheter-bearing needle to access the port without difficulty. In addition, the access port includes a valve/seal assembly to permit the injection of fluids through the access port at a relatively high flow rate, such as about <NUM> per second at a pressure of about <NUM>,<NUM> bar (<NUM> psi) (also referred to herein as "power injection"). Possible applications for the access port described herein include administration of medicaments and other fluids to the patient, pheresis, fluid aspiration, etc..

Reference is first made to made to <FIG>, which show various details of an access port, generally designated at <NUM>, in accordance with one embodiment. As shown, the port <NUM> includes a body <NUM> that is defined in the present embodiment by a first portion 12A and a second portion 12B (<FIG>). In the present embodiment the port body <NUM> includes a metal such as titanium, and as such, the second portion 12B is press fit into engagement with the first portion 12A to define the body, though it is appreciated that the port body can include a variety of other materials, including metals, thermoplastics, ceramics, etc..

The port body <NUM> defines in the present embodiment a substantially concavely-shaped receiving cup <NUM> for receiving and directing a catheter-bearing needle (<FIG>) to operably connect with the port <NUM>, as described further below. In particular, the substantially concave shape of the receiving cup <NUM> is configured to direct a catheter-bearing needle (<FIG>) impinging thereon toward an inlet port <NUM> that serves as an opening for a conduit <NUM> defined by the port body <NUM>. The open and shallow nature of the receiving cup <NUM> together with its substantially upward orientation (i.e., toward the skin surface of the patient), so that it is substantially parallel to the skin surface when subcutaneously implanted under the skin of the patient (i.e., the receiving cup is substantially parallel to the skin surface when the skin is at rest, or undeformed by digital pressure or manipulation), enables the receiving cup to present a large, easily accessible target for the needle when introduced into the skin, as seen in <FIG> further shows that the port <NUM> defines a relatively low profile height, which enables relatively shorter needle lengths to be used for accessing the port after implantation.

Palpation features <NUM> are included with the port body <NUM> to assist a clinician to locate and/or identify the port <NUM> via finger palpation after implantation under the skin of the patient. In detail, the palpation features <NUM> in the present embodiment include a bump 26A disposed near the proximal end of the receiving cup <NUM> and a ridge 26B disposed above and curving around a distal portion of the receiving cup. <FIG> shows that the palpation features extend above the general upper plane defined by the port <NUM> so as to facilitate palpation of the features by a clinician in order to locate the position and/or orientation of the receiving cup <NUM>. Note that a variety of other sizes, configurations, numbers, etc., of palpation features can be included on the port in addition to what is shown and described herein.

A guide groove <NUM> is defined on the receiving cup <NUM> and is longitudinally aligned with the inlet port <NUM> of the conduit <NUM>. The guide groove <NUM> is defined as a depression with respect to adjacent portions of the surface of the receiving cup <NUM> and extends distally along the receiving cup surface from a proximal portion of the receiving cup so as to provide a guide path to guide the distal tip of the catheter-bearing needle toward the inlet port <NUM> once impingement of the needle into the guide groove is made. This in turn reduces the chance the needle will slide across and off the receiving cup <NUM> during insertion. Note that these and other similar features, though differing in shape and configuration, can also be included on the other ports disclosed herein.

As best seen in <FIG>, the port body <NUM> further defines the conduit <NUM> as a pathway into which a transcutaneously inserted catheter can pass so as to place the catheter in fluid communication with the port <NUM>. As shown, the conduit <NUM> is in communication with the receiving cup <NUM> via the inlet port <NUM>. A first conduit portion 18A of the conduit <NUM> distally extends from the inlet port <NUM> in an angled downward direction from the perspective shown in <FIG> to a bend <NUM>, where a second conduit portion 18B of the conduit angles slightly upward and changes direction at a predetermined angle (<NUM>°-θ<NUM>). Note that angle orientation (<NUM>°-θ<NUM>) in one embodiment is about <NUM> degrees, but can vary from this in other embodiments, including angles less than <NUM> degrees in one embodiment. The magnitude of angle θ<NUM> depends in one embodiment on various factors, including the size of the catheter and/or needle to be inserted into the port conduit, the size of the conduit itself, etc..

The conduit <NUM> then extends to and through a cavity 20A defined by a valve housing <NUM> of the port body. The conduit <NUM> extends to a distal open end of the stem <NUM> of the port <NUM>. The conduit <NUM> is sized so as to enable the catheter <NUM> (<FIG>) to pass therethrough, as will be seen.

As mentioned, the valve housing <NUM> defines a cavity 20A through which the conduit passes and which houses a valve/seal assembly <NUM>. The valve/seal assembly <NUM> includes a sealing element, or seal <NUM>, which defines a central hole through which the catheter <NUM> can pass, a first slit valve 34A and a second slit valve 34B. The seal <NUM> and valves 34A, 34B are sandwiched together in one embodiment and secured in place within the cavity 20A as shown in <FIG>. The slits of the slit valves 34A, 34B are rotationally offset from one another by about <NUM> degrees in the present embodiment, though other relationships are possible.

The seal <NUM> and valves 34A, 34B of the valve/seal assembly <NUM> cooperate to enable fluid-tight passage therethrough of the catheter <NUM> (<FIG>) while also preventing backflow of fluid through the valve/seal assembly. Indeed, in one embodiment the seals disclosed herein prevent fluid flow around the external portion of the catheter when the catheter is disposed through the seal, while the valves are suitable for preventing fluid flow when no catheter passes through them. As such, when the catheter <NUM> is not inserted therethrough the valve/seal assembly <NUM> seals to prevent passage of air or fluid. In the present embodiment, the seal <NUM> and valves 34A, 34B include silicone, though other suitably compliant materials can be employed.

The port <NUM> in the present embodiment includes an overmolded portion <NUM> that covers the port body <NUM>. The overmolded portion <NUM> includes silicone or other suitably compliant material and surrounds the body <NUM> as shown so as to provide a relatively soft surface for the port <NUM> and reduce patient discomfort after port implantation. The overmolded portion <NUM> includes two predetermined suture locations <NUM>, best seen in <FIG>, for suturing the port <NUM> to patient tissue, though sutures may be passed through other portions of the overmolded portion, if desired. The overmolded portion <NUM> further defines a relatively flat bottom surface 36A so as to provide a stable surface for the port <NUM> in its position within the tissue pocket after implantation. In contrast, the port shown in <FIG> includes a bottom surface with a slightly rounded profile.

<FIG> depicts details regarding the insertion of the catheter <NUM> disposed on the needle <NUM>, according to one embodiment. After locating the port <NUM> via through-skin palpation of the palpation features <NUM>, a clinician uses the catheter-bearing needle <NUM> to pierce a skin surface <NUM> and insert the needle until a distal tip 42A thereof impinges on a portion of the receiving cup <NUM>, as shown. Note that, because of the orientation of the receiving cup <NUM> as substantially parallel to the skin surface, the needle <NUM> can impinge on the receiving cup at an insertion angle θ<NUM> that is relatively steep, which facilitates ease of needle insertion into the body. Indeed, in one embodiment a needle inserted substantially orthogonally through the skin of the patient can impinge the receiving cup of the access port.

The needle <NUM> is manipulated until the distal tip 42A is received into the guide groove <NUM>, which will enable the distal tip to be guided along the groove to the inlet port <NUM>. The needle <NUM> is then inserted through the inlet port <NUM> and into the first portion 18A of the conduit <NUM> until it is stopped by the bend <NUM>. The needle <NUM> can then be proximally backed out a small distance, and the catheter <NUM> advanced over the needle such that the catheter bends and advances past the bend <NUM> into the second portion 18B of the conduit <NUM>. Catheter advancement continues such that a distal end 40A of the catheter <NUM> advances into and past the hole of the seal <NUM> and through both slits of the slit valves 34A, 34B of the valve/seal assembly <NUM>. Once the distal end 40A of the catheter <NUM> has extended distally past the valve/seal assembly <NUM>, further advancement can cease and fluid transfer through the catheter <NUM> and port <NUM> can commence, including infusion and/or aspiration through the stem <NUM>. Once fluid transfer is completed, the catheter <NUM> can be withdrawn proximally through the valve/seal assembly <NUM> and the conduit, then withdrawn through the surface <NUM> of the skin and out of the patient.

<FIG> depict details of an access port <NUM> according to another embodiment. Note that various similarities exist between the port <NUM> and the other ports shown and described herein. As such, only selected port aspects are discussed below. As shown, the port <NUM> includes a body <NUM> that in turn includes a first body portion 112A and a second body portion 112B, best seen in <FIG>. The body <NUM> in the present embodiment includes a thermoplastic, such as an acetyl resin in the present embodiment. As such, the first and second body portions 112A, 112B are ultrasonically welded to one another to define the body <NUM>, in the present embodiment. As before, a receiving cup <NUM> is included with the body <NUM> and is operably connected to a conduit <NUM> via an inlet port <NUM>. Also, note that a variety of materials can be used to define the port body, receiving cup, conduit, etc..

A valve/seal assembly <NUM> is disposed within a cavity 120A that is defined by a valve housing <NUM>, which in the present embodiment, is defined by the first body portion 112A. The valve/seal assembly <NUM> includes a proximal seal <NUM> with a central hole for catheter passage, two slit valves 134A, 134B each with a slit arranged at a <NUM>-degree offset with respect to the other, and a distal seal <NUM> with a central hole, also referred to herein as a sphincter seal.

The distal seal <NUM> includes on its distal surface a frustoconical portion 135A disposed about the seal central hole that is configured to provide a sphincter-like seal about the outer surface of a catheter when it extends through the valve/seal assembly. The frustoconical portion 135A is disposed such that any back-flowing fluid impinging on the frustoconical portion will cause the seal to secure itself about the outer surface of the catheter in an even tighter engagement, thus preventing backflow past the catheter outer surface when high fluid pressures are present, such as in the case of power injection. As mentioned, other valve/seal combinations can also be included in the valve/seal assembly.

In the present embodiment, the receiving cup <NUM> and portion of the conduit <NUM> proximal to the valve/seal assembly <NUM> both include a needle-impenetrable lining that prevents the distal end of a needle from gouging the surface when impinging thereon. This, in turn, prevents the undesirable creation of material flecks dug by the needle. Various suitable materials can be employed for the needle-impenetrable material, including glass, ceramic. metals, etc. In one embodiment, the components of the port <NUM> are all non-metallic such that the port is considered MRI-safe, by which the port does not produce undesired artifacts in MRI images taken of the patient when the port is in implanted therewithin.

<FIG> depicts additional features of the port <NUM> according to another embodiment. As shown, in the present embodiment the receiving cup <NUM> includes radiopaque indicia <NUM> to indicate a characteristic of the port <NUM>. Here, the radiopaque indicia <NUM> includes a "C" and a "T" that are formed by a radiopaque material, such as tungsten, bismuth trioxide, etc., so as to be visible after port implantation via x-ray imaging technology. For instance, the radiopaque material can be formed as an insert that is insert-molded included in the port body, as an initially flowable material that is injected into a cavity of the port body before hardening, etc. In embodiments where the port body is metallic, the radiopaque indicia can be formed by etching, engraving, or otherwise producing a relative thickness difference between the indicia and the surrounding port body material so as to produce an x-ray-discernible contrast that shows up in an x-ray image.

In the present embodiment, the CT radiopaque indicia <NUM> indicate to an observer that the port is capable of power injection of fluids therethrough. In addition to this characteristic, other characteristics can be indicated by various other types of indicia as appreciated by one skilled in the art.

Further, in the present embodiment the top view of the port <NUM> of <FIG> indicates that the port body <NUM> in the region surrounding the receiving cup <NUM> defines a generally triangular shape, which can be palpated by a clinician after implantation and can indicate not only the location of the receiving cup, but also a particular characteristic of the port, such as its ability to be used for power injection. Of course, the receiving cup may define shapes other than triangular in other embodiments.

<FIG> further shows that distributed about the perimeter of the receiving cup <NUM> are three palpation features <NUM>, namely, three suture plugs 126A disposed in corresponding holes defined in the port body <NUM>. The suture plugs 126A include raised silicone bumps in the present embodiment and can serve to locate the position of the receiving cup <NUM> post-implantation when they are palpated by a clinician prior to needle insertion into the patient. Various other palpation features could be included with the port, in other embodiments.

<FIG> depicts details of a low-profile port <NUM> according to one embodiment, including a body <NUM> defining a concavely-shaped receiving cup <NUM> and an inlet port <NUM> positioned slightly off-center with respect to the receiving cup. A stem <NUM> is included as a fluid outlet.

<FIG> depicts the low-profile port <NUM> according to another embodiment, wherein the body <NUM> defining additional surface features, including a raised palpation feature <NUM> distal to the receiving cup <NUM>. In light of <FIG> and <FIG>, it is thus appreciated that the port can be configured in a variety of shapes and configurations to provide a low-profile solution for providing vascular access. Note also that the receiving cup shape, design, and configuration can vary from is explicitly shown and described herein.

<FIG> and <FIG> depict various details of a low-profile dual-body access port <NUM> according to one embodiment, wherein each of the port bodies <NUM> defines a receiving cup <NUM> that is laterally facing and includes an inlet port <NUM> leading to a conduit <NUM>. The conduit <NUM> extends distally to a valve/seal assembly <NUM> disposed in a valve housing <NUM>, which in the present embodiment, is defined by a portion of the body <NUM>. The conduit <NUM> extends through the port <NUM>. A compliant overmolded portion <NUM> covers portions of each body <NUM> of the port <NUM> and operably joins the bodies to one another. The bodies <NUM> can include any suitable material, including metal, thermoplastic, etc..

<FIG> and <FIG> depict various details of a low-profile dual-body access port <NUM> according to one embodiment, wherein a port body <NUM> defines dual fluid paths. Each fluid path includes a receiving cup <NUM> defined by the body <NUM> and facing a substantially upward orientation from the perspective shown in <FIG> and <FIG>. An inlet port <NUM> is included with each receiving cup <NUM> and defines the opening to a conduit <NUM>. Each conduit <NUM> extends distally to a valve/seal assembly <NUM> disposed in a valve housing <NUM>, which in the present embodiment, is defined by a portion of the body <NUM>. The conduit <NUM> extends through the port <NUM>. The body <NUM> can include any suitable material, including metal, thermoplastic, etc..

Claim 1:
A low-profile access port for subcutaneous placement in a patient, comprising: a body (<NUM>) including:
a conduit (<NUM>) including an inlet port (<NUM>) at a proximal end thereof; and
a receiving cup (<NUM>) in communication with the inlet port (<NUM>), the receiving cup (<NUM>) concavely shaped to direct a catheter-bearing needle into the conduit (<NUM>) via the inlet port (<NUM>), the receiving cup to be oriented substantially toward a skin surface when subcutaneously implanted within the patient, so as to have a substantially upward orientation; and
a valve/seal assembly (<NUM>) disposed in the conduit (<NUM>) that enables passage of the catheter therethrough,
wherein the conduit (<NUM>) includes a first conduit portion (18A) and a second conduit portion (18B), the second conduit portion positioned distal to and at an angled orientation with respect to the first conduit portion so as to prevent passage of the needle of the catheter-bearing needle while permitting passage of the catheter, and the second conduit portion (18B) is disposed at an angle less than about <NUM> degrees with respect to the first conduit portion (18A),
characterized in that the first conduit portion (18A) extends distally from the inlet port (<NUM>) in an angled downward configuration to a bend (<NUM>), where the second conduit portion (18B) angles slightly upward and changes direction at the angle less than about <NUM> degrees.