Patent Description:
Deflecting catheters, also referred to as steerable catheters are used in a variety of medical and non-medical procedures. In diagnostic and therapeutic medical procedures, a steerable catheter provides an operator (e.g., physician) with the ability to articulate the distal tip of the catheter in order to travel through constrained and/or tortuous anatomy, and/or to direct the distal catheter tip in a particular direction. Similar mechanisms are used in medical and nonmedical endoscopes to steer them to a target site and to orient a device portion (e.g., including a camera or other visualization means) in a desired direction.

In a typical design, control wires are manipulably attached at a proximal end of the device, and also attached at or near a distal end of the device. Such a configuration operates by manipulating one or more of the control wires to increase and/or decrease a generally longitudinal force on the distal device end that will deflect it in a desired direction. As described with reference to an existing steerable endoscopic camera device <NUM> of <FIG>, the control wires may be actuated by rotation of control wheels <NUM>, <NUM>. Each control wheel can be rotated to operate a control wire or pair of control wires in a manner exerting push/pull tension on a deflectable distal device portion (not shown, but well-known in the art) to deflect that portion along a first plane, while the other control wheel operates similarly to deflect that portion along a second plane intersecting (e.g., orthogonal to) the first plane. At times, it is desirable to lock that distal device portion into a particular deflected orientation (e.g., so that the operator may execute another task requiring releasing hand contact with one or both control wheels). The illustrated device <NUM> includes a first brake for the first control wheel <NUM>, with a twistable knob <NUM> for locking/unlocking an internal brake mechanism that operates along the central rotational axis of the first control wheel <NUM>. The illustrated device <NUM> includes a second brake for the second control wheel <NUM>, with a lever <NUM> for locking/unlocking an internal brake mechanism that operates by exerting a braking engagement along the central rotational axis of the second control wheel <NUM>. One or both brake controls <NUM>, <NUM> require a user to change his/her grip for actuation.

A variety of different steerable shaft constructions have been used in different prior catheters and endoscopes. Each shaft typically has at least one working channel that extends longitudinally therethrough (e.g., through a working channel port <NUM> in the handle, shown capped). A steerable catheter device may be configured as a gastrointestinal duodenoscope with a distal terminal end construction 59a as shown in <FIG> or as an endoscopic ultrasound (EUS) endoscope with a distal terminal end construction 59b as shown in <FIG>, which also shows a tool structure extending out through that scope's working channel lumen.

However, there are special challenges and needs for a small-diameter catheter (e.g., less than <NUM>, less than <NUM>, or less than <NUM>) configured for use through a side-viewing endoscope - such as a duodenoscope, potentially including designs like those shown in <FIG>. In particular, such a device will need different resistance to crimping, kinking, and/or collapse along its length during operation and manipulation - including during introduction into and operation within a biliary tree of a human or non-human patient. Further, it is desirable for a handle of a steerable catheter device to attach directly and rigidly to a working port of a larger endoscope, for which reason it is desirable to have the handle to include physical features and functions that provide for management of fluid and vacuum, while also providing for operation of a camera, light element(s), steering along and between all four transverse axes relative to a catheter device shaft, and robust construction.

It would be desirable to provide a catheter shaft design that is configured and dimensioned for operation as a cholangioscope. Moreover, there is a need for a catheter device like this that provides diagnostic, therapeutic, and economic benefit to patients and caregivers by providing reliably predictable operative functionality and resistance to impaired structure or function during typical operations.

<CIT> discloses medical visualization systems that comprise combinations of disposable and reusable components. <CIT> discloses an endoscope mountable visualization device and handle. <CIT> discloses an endoscope mountable visualization device quick-connect/release handle attachment mechanism. <CIT> discloses a secondary endoscope which can be attached to a parent endoscope.

The subject matter of the present invention is defined by the appended claims.

More generally, the present disclosure provides, in one aspect, a handle for a steerable catheter device, including an endoscopy device such as a cholangioscope, as well as methods for making such a device.

In one aspect, embodiments disclosed herein may include steerable catheter handle including: an outer housing; a multilumen catheter body extending generally distally from the outer housing; a mounting mechanism at or near a distal terminal end of the outer housing; an internal track, disposed between the distal terminal end of the outer housing and a proximal terminal end of the outer housing, the internal track including means to define a track for the catheter body (<NUM>) to be removably directed from a generally proximal catheter port (<NUM>) through to a central opening of the mounting mechanism (<NUM>); a manifold engaged with the multilumen catheter body; a working channel port member extending outside an outer housing exterior surface and providing a path in fluid communication with at least a first lumen of the multilumen catheter; a vacuum channel port member in fluid communication with at least one lumen of the multilumen catheter via one or both of the working channel port member and the manifold; and a generally proximal catheter port open through an outer housing exterior surface and providing a path of mechanical communication with the internal track; where at least a distal endmost portion of the multilumen catheter is in mechanical communication with one or more control surfaces of the handle portion such that the distal endmost portion of the multilumen catheter is deflectable along at least two intersecting axes; and where a portion of the multilumen catheter body extends removably through the internal track.

Various embodiments are described below with reference to the drawings in which like elements generally are referred to by like numerals. The relationship and functioning of the various elements of the embodiments may better be understood by reference to the following detailed description. However, embodiments are not limited to those illustrated in the drawings. It should be understood that the drawings may be but are not necessarily to scale, and in certain instances details may have been omitted that are not necessary for an understanding of embodiments disclosed herein, such as - for example -conventional fabrication and assembly.

Generally, the steerable catheter handle embodiments of the present disclosure provide structure for a small-diameter deflectable/ steerable catheter (including one provided with visualization elements for use as an endoscope) to be attached to a larger "parent" scope, and with an internal manifold that provides structure for effective operation of the steerable shaft portion including manipulation and passage of fluids and/or devices.

The invention is defined by the claims, may be embodied in many different forms, and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey enabling disclosure to those skilled in the art. As used in this specification and the claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Reference herein to any industry standards (e.g., ASTM, ANSI, IEEE standards) is defined as complying with the currently published standards as of the original filing date of this disclosure concerning the units, measurements, and testing criteria communicated by those standards unless expressly otherwise defined herein.

The terms "proximal" and "distal" are used herein in the common usage sense where they refer respectively to a handle/doctor-end of a device or related object and a tool/patient-end of a device or related object. The terms "about," "substantially," "generally," and other terms of degree, when used with reference to any volume, dimension, proportion, or other quantitative or qualitative value, are intended to communicate a definite and identifiable value within the standard parameters that would be understood by one of skill in the art (equivalent to a medical device engineer with experience in this field), and should be interpreted to include at least any legal equivalents, minor but functionally-insignificant variants, standard manufacturing tolerances, and including at least mathematically significant figures (although not required to be as broad as the largest range thereof).

Embodiments of a handle are described with reference to <FIG>, where <FIG> shows a steerable catheter device of the present disclosure including a handle portion assembly <NUM> with a steerable catheter body <NUM> extending distally therefrom (which may have a default straight linear configuration, and for which is illustrated only a slightly-deflected distal end terminal lengthwise portion). Various embodiments may include one or more different steering control means known in the art. This illustrated embodiment includes a pair of control wheels, with an outer control wheel <NUM> and an inner control wheel <NUM>. As set forth in greater detail below (including with reference to <FIG>), the outer control wheel <NUM> is disposed in mechanical communication with a pair of control wires that are operable, upon wheel rotation, to deflect at least the end portion <NUM> of the catheter body <NUM> along a first plane, and the inner control wheel <NUM> is disposed in mechanical communication with another pair of control wires that are operable, upon wheel rotation, to deflect the catheter body <NUM> along a second plane that may be generally orthogonal to the first plane, and is at least somewhat offset from that first plane. Simultaneous or sequential operation of the outer and inner wheels <NUM>, <NUM> preferably will deflect the distal end portion <NUM> of the catheter body <NUM> in any direction around a <NUM>-degree circle defined generally by a circumference of the catheter. The phrase "generally orthogonal" is used to refer to the objects being perpendicular, or very nearly so (for example, within <NUM>° to <NUM>°; in one embodiment, by way of non-limiting example, the planes may be offset by <NUM>°/<NUM>° as shown in <FIG> with reference to the position and orientation of the parallel control wire lumens).

Steering mechanisms using control wires are well-known in the art including in <CIT> to Williams. The overall control structure described is also well known in the steerable device art, including particularly the endoscope art, but those devices lack the currently disclosed finely-controlled mechanism for efficient and effective tensioning of control wires. Certain embodiments in keeping with the present disclosure may include at least one visualization element (as well as supporting hardware and/or software, not shown - but well-known in the art and readily understandable as using electrical and/or optical devices such as CCD, fiber optic, CMOS, etc.) for use of such embodiments as endoscopic devices including, for example, as a cholangioscope configured for use with and through a larger endoscope. The illustrated handle embodiment <NUM> is configured for secure attachment to a working channel of a larger endoscope (e.g., as shown in <FIG>), and it may include any number of different attachment/ mounting mechanisms <NUM>, such as - for example - those described and illustrated in <CIT> and/or <CIT>.

In <FIG>, a strain-relief sheath <NUM> is shown attached to and extending from a near-distal catheter-base port <NUM> of the handle housing <NUM>, which strain-relief sheath is described below in greater detail. A vacuum channel port member <NUM> and a flush port member <NUM> are also shown adjacent the near-distal catheter-base port <NUM> of the handle housing <NUM>. A working channel port member <NUM> extends from a proximal end portion 161a of the handle housing <NUM> and provides for mechanical and fluid communication with at least one lumen of the catheter <NUM>. As used herein, a path or structure providing "fluid communication" refers to a lumen or passage at least partially enclosed that is dimensioned and otherwise configured for movement therethrough of liquid and gas. As used herein, a path or structure providing "mechanical communication" refers to a lumen or passage at least partially enclosed that is dimensioned and otherwise configured for movement therethrough of a physical object (e.g., an endoscopic tool such as a needle, biopsy pincers, sphincterotome, needle-knife, guidewire, or other device).

The exploded views of <FIG> show internal components and relative position/arrangement thereof, but certain components not being claimed in the present disclosure are not described in any detail. These views are shown positioned adjacent to a partially-illustrated larger steerable device such as an endoscope <NUM>, where -as noted above-embodiments of the present device may be securely mounted thereto in a manner with the present catheter <NUM> extending into the working channel port <NUM>. Most of the internal components are assembled between the first and second halves 102a, 102b of the handle housing <NUM>. As shown in <FIG> and <FIG>, the multilumen catheter body <NUM> extends from a manifold <NUM> out through the near-distal catheter-base port <NUM> (through a strain relief sheath <NUM>, if present) and loops around to re-enter a proximal catheter-track port <NUM> of the handle housing <NUM>. The internal track is described below with reference to <FIG>.

The track does not need to be fully enclosed by other structures within the housing, but includes at least one track-defining lateral edge element <NUM>, which helps define a track for the catheter body <NUM> to be removably directed from the proximal catheter-track port <NUM> through to an through a central opening of the distal mounting/ attachment structure <NUM>, through which that catheter body <NUM> may enter the working channel of a larger scope. In the exploded view of <FIG>, the track is provided with a track tube <NUM> configured to provide a closed, fluid-patent path of mechanical communication from the proximal catheter-track port <NUM> to the near-distal catheter-base port <NUM>. The track tube <NUM> is also shown in <FIG> (in phantom line), with the catheter body extending through its longitudinal central lumen but is not shown in <FIG>. The track-defining lateral edge elements <NUM> do not need fully to enclose the track, but - as illustrated - serve to laterally stabilize the track tube <NUM> and hold it in alignment for a smooth transit of the catheter body <NUM> through a central longitudinal lumen of the track tube <NUM>. As such, the portion of the multilumen catheter body <NUM> extending movably through the internal track can be removed entirely from the track while remaining attached to and extending generally distally from the outer housing <NUM>. By "generally distally," it is meant that where the catheter is fixedly attached to the handle body, the catheter extends at a downward angle of less than <NUM>° or less relative to the longitudinal axis from top to bottom of the handle body. Those of skill in the art, informed by the present disclosure, will appreciate that the internal mechanical/structural arrangement of the catheter, manifold, and communicating structures can be reversed (e.g., top-bottom) or otherwise oriented within a handle body, within the scope of the present disclosure.

In <FIG>, the working channel port member <NUM> and the manifold <NUM> are shown in longitudinal section (halfway through their lateral thicknesses). The working channel port member <NUM> includes a first longitudinal lumen <NUM> that provides fluid communication and mechanical communication (via the lumen of an intermediate first extension tube 166a and the manifold <NUM>) with a working channel lumen <NUM> of the catheter body <NUM>. Near the distal end of the working channel port member <NUM>, a transverse channel <NUM> provides a path of fluid communication between a short second longitudinal lumen <NUM> and the first longitudinal lumen <NUM>. An outside end terminus of the transverse channel <NUM> is shown as being sealed with a ball member 167a. The second longitudinal lumen <NUM> is in communication (via the lumen of an intermediate second extension tube 168a) with the vacuum channel port member <NUM>. Each of the intermediate first extension tube 166a and the intermediate second extension tube 168a may be attached to the working channel port member <NUM> by that working channel port member <NUM> being overmolded around them to form a secure attachment with fluid-patent inner lumens.

This construction enables providing a vacuum to the working lumen <NUM> of the catheter <NUM>, even when a diagnostic tool, therapeutic tool, or other device is attached to the working channel port member <NUM> and is occupying some or even most of the first longitudinal lumen <NUM> and the working lumen <NUM> of the catheter <NUM>. During procedures, this provides for management of fluids (e.g., bodily fluids, flushing fluids) that can migrate up the working lumen <NUM>. The orientation and position of the vacuum channel port member <NUM> keeps it out of the way for an operator who is manipulating the catheter <NUM>, control wheels <NUM>, <NUM>, and other device features (see, e.g., <FIG>, which shows a vacuum line 141p with vacuum valve 141q extending from the vacuum channel port member <NUM>).

The manifold <NUM> is shown in <FIG>, with reference also to <FIG>. As shown in <FIG>, with reference also to <FIG>, a first longitudinal manifold lumen 170a is in fluid and mechanical communication (via the lumen of the intermediate first extension tube 166a) with the catheter working lumen <NUM>. The first longitudinal manifold lumen 170a communicates with the catheter working lumen <NUM>, as shown in <FIG> and <FIG>, via a skived opening 164a through the side wall of the catheter <NUM>. A perspective view of the proximal terminal end of the catheter body <NUM> is shown in <FIG>, including showing the catheter lumens: working lumen <NUM>, control wire lumens <NUM>, <NUM>, <NUM>, <NUM>, and other channels that may be used, for example, for one or more of light source(s), camera or other visualization device, wire guide, vacuum, flushing, other accessories/tools, or other purposes and/or objects. The control wire lumens receive the control wires (shown with termination in <FIG>), and those wires provide mechanical communication between one or more control surfaces (e.g., wheels <NUM>, <NUM>) and the distal endmost portion <NUM> of the multilumen catheter body <NUM> so that the body will be deflectable along at least two intersecting axes.

As shown with reference to <FIG> and <FIG>, the flush port member <NUM> is illustrated as being disposed generally orthogonal to the longitudinal axis of the multilumen catheter body <NUM>, to the manifold <NUM> with which the flush port member is attached, and to the manifold first lumen 170a. The flush port member <NUM> provides a path of fluid communication with at least one lumen of the multilumen catheter body <NUM> via a flush port skive 143a through the side wall of the catheter <NUM>. The flush port skive 143a may open to the working lumen <NUM>, but preferably is oriented radially about <NUM>° from, and longitudinally near, the working lumen side skive 164a. In this position and orientation, the flush port skive 143a may open to a different lumen of the catheter body, which - in many embodiments will be a lumen other than the working lumen <NUM>. As shown in the drawings, the multilumen catheter extends proximal of, through, and distal of the manifold, including extending out of the handle housing <NUM>, then looping back around to extend movably and removably through its inner track and through the bottom distal terminal end of the handle housing. As shown in the drawings, the bottom/distal end of the manifold, from which the catheter <NUM> extends, is disposed at an acute angle relative to the bottom/ distal end of a longitudinal axis of the handle body <NUM>.

Each of the intermediate first extension tube 166a and the near-proximal end region of the catheter body <NUM> may be attached to/in the manifold <NUM> by the manifold being overmolded around them to form a secure attachment with fluid-patent inner lumens as described above. The flush port member <NUM> may be formed as a unitary part with the manifold <NUM>, or as a separate member. In preferred embodiments, such as illustrated here, the common lumen extending through each of the working channel port member <NUM>, intermediate first extension tube 166a, and manifold <NUM> provides a nearly straight/ only slightly-curved path to minimize friction for tools being directed into and operated through the catheter working lumen <NUM> (with which that common lumen is continuous for both fluid and mechanical communication). When present, the strain relief sheath <NUM> helps to keep the catheter body <NUM> curvature out of, then back around into, the inner track of the handle body <NUM> at a larger radius, less-tightly-curved configuration (than the catheter without sheath) for the same reason, as minimizing friction will make operation of the steerable catheter and any tools used therethrough easier for operators and more mechanically efficient. Specifically, this configuration provides for reduced force of introduction of one or more tools through the catheter body lumen(s), and for reduced force required to operate those tools (e.g., needles, forceps, other diagnostic and/or therapeutic devices) when disposed to a target site via the catheter body - where the force is reduced as compared to other potential embodiments where the catheter body <NUM> would include and/or traverse tighter curves or bends.

The strain relief sheath <NUM> is described with further reference to <FIG>. In <FIG> is shown two opposite-side views of the strain relief sheath <NUM>, and <FIG> shows a transverse section view thereof, taken along line 5B-5B of <FIG>. As shown in other drawing figures including at least <FIG>, the strain relief sheath <NUM> is configured to provide support for and around the length of the catheter body <NUM> that extends out from between the near-distal catheter-base port <NUM> and loops back around along an arc to the proximal catheter-track port <NUM>. The strain relief sheath <NUM> preferably is made of a softer polymer than the proximal length of the catheter shaft, such as - for example - a Shore 78A polymer (where the proximal shaft length may be formed from a Shore <NUM> polymer or polymer blend). As shown in <FIG>, with particular reference to the section view of <FIG>, the strain relief sheath <NUM> includes a longitudinal lumen <NUM> extending through its entire length, and open along one lateral side via a slot 127x. The strain relief sheath lumen <NUM> has an inner diameter that preferably is about the same as, exactly the same as, or very slightly less than the outer diameter of the catheter shaft <NUM>. The radial width of the strain relief sheath slot 127x is less than the outer diameter of the catheter shaft <NUM>.

The strain relief sheath <NUM> is formed in a semicircular or other rounded form as illustrated (<FIG>) to support the catheter <NUM> along the length already described and also resists kinking or crimping of any portion of the catheter body extending longitudinally through a longitudinal lumen of the strain relief sleeve. In particular, those of skill in the art will appreciate that actuation of the control wheels in a manner tensioning the control wires to steer/deflect the distal end of the catheter body requires transmitting force along those control wires. Because of the small diameter of the proximal catheter length <NUM>, when subjected to such force, it would be prone to curving, buckling, or otherwise being distorted in a manner that would reduce the effective transmission of force from the handle to the distal catheter end. The strain relief sheath <NUM> provides radial support so that the force can more effectively be transmitted along the natural/default curved path (between the near-distal catheter-base port <NUM> and the proximal catheter-track port <NUM>, described above) without distortion of the proximal catheter body portion, and minimal out-of-plane movement that would disperse the force transmission.

As shown in <FIG>, the strain relief sheath <NUM> may include semi-circumferential indented surfaces 124d along opposed sides. These indented surfaces 124d provide greater flexibility in the primary plane of the sheath body along which the catheter <NUM> curves, while simultaneously providing lesser flexibility for the sheath <NUM> to flex out of that primary plane. In the event that a greater length of the catheter body <NUM> needs to be advanced through the handle <NUM> than is allowed when fully engaged in the sheath <NUM>, the sheath <NUM> can be peeled back with the catheter shaft <NUM> exiting through the slot 127x - for example from the distal sheath end as illustrated in <FIG> so that a distalmost length of the sheath <NUM> is no longer around the catheter body <NUM>. In the embodiment illustrated, the strain relief sheath <NUM> may be constructed of a Santoprene™ polymer, about <NUM>-<NUM> in length (from the handle <NUM> to the distal end of the sheath <NUM>), and curving within a circle of about <NUM>-<NUM> in diameter.

The indentations 124d may be configured as visible indicia of length at regular intervals. In certain embodiments, the strain relief sheath <NUM> may include at least one external friction clip member dimensioned for engaging an outer diameter portion of the multilumen deflectable catheter body, or another structure. The embodiment depicted herein, including in <FIG>, includes two clips. A proximal clip <NUM> includes a flexible/resilient pronged structure for clamping around a cord or cable. For example, in some embodiments an HDMI or other cable being used for data transmission (e.g., images) can be clipped into the proximal clip <NUM>, or a cable or other columnar structure of a secondary device (not shown) being used with/through the overall device <NUM> (e.g., electrohydraulic lithotripsy cable) can be secured in the proximal clip <NUM> to help with device management and to relieve weight/stresses on a connection of that secondary device to the primary steerable catheter device <NUM>. A distal clip 124n is also shown, which can be used to clip/hold a portion (e.g., distal or other length) of the catheter body - for example, during shipping, initial handling before introduction into/through a larger scope, or other use that will minimize the number of people needed in a suite for device management and that will make overall device handling more convenient for users.

Claim 1:
A steerable catheter device, comprising:
a handle portion (<NUM>) including
an outer housing (<NUM>);
a multilumen catheter body (<NUM>) extending generally distally from the outer housing;
a mounting mechanism (<NUM>) at or near a distal terminal end of the outer housing;
an internal track, disposed between the distal terminal end of the outer housing and a proximal terminal end of the outer housing, the internal track including means to define a track for the catheter body (<NUM>) to be removably directed from a generally proximal catheter port (<NUM>) through to a central opening of the mounting mechanism (<NUM>);
a manifold (<NUM>) engaged with the multilumen catheter body;
a working channel port member (<NUM>) extending outside an outer housing exterior surface and providing a path in fluid communication with at least a first lumen (<NUM>) of the multilumen catheter;
a vacuum channel port member (<NUM>) in fluid communication with at least one lumen (<NUM>) of the multilumen catheter via one or both of the working channel port member and the manifold; and
a generally proximal catheter port (<NUM>) open through an outer housing exterior surface and providing a path of mechanical communication with the internal track;
where at least a distalmost portion (<NUM>) of the multilumen catheter is in mechanical communication with one or more control surfaces (<NUM>, <NUM>) of the handle portion such that the distalmost portion of the multilumen catheter is deflectable along at least two intersecting axes; and
where a portion of the multilumen catheter body extends removably through the internal track.