Patent Description:
A catheter is a medical instrument for use in accessing an interior of a patient's body with a distal tip during a medical procedure. The catheter can include at least one working component, such as a fluid channel, a working channel, and/or an electronics cable, which extend along the catheter and terminate at or adjacent the distal tip. Catheters typically have a control handle which is configured to allow a user to control a position of the distal tip during the procedure, such as via rotation of a knob on the control handle to effectuate rotation of the catheter and the distal tip about an axis. However, the working components which pass through the catheter shaft are prone to winding, overlapping, occlusion or other damage during their simultaneous rotation with the catheter shaft. Torsional stresses and crossing of the working components caused during rotation of the catheter shaft can damage or impair the function of the catheter device. For example, the fluid channel is utilized to deliver fluids and the working channel is utilized to deliver an instrument to the distal tip of the catheter during the medical procedure. However, kinking, crossing or other occlusion of these channel components can prevent the related fluids or instrument from reaching the distal tip during the medical procedure, and thus resulting in an ineffective catheter that fails during the medical procedure. Additionally, knotting or worse yet facture of the electronics cable can lead to full loss of function of the electronics. Thus, there remains a need for improvements to such catheter control assemblies in which the catheter shaft is rotatable about the axis during the medical procedure by a user and includes at least one working component.

An example of a control assembly for a catheter having a channel with a static and a dynamic portion is known from <CIT>.

A control assembly for a catheter having at least one working component includes a housing extending along an axis between a proximal housing end and a distal housing end to define a housing compartment extending therebetween. A control case is disposed within the housing compartment adjacent the proximal housing end. A catheter shaft extends within the housing compartment from the control case to a distal tip disposed adjacent the distal housing end. The catheter shaft is rotatable about the axis during operation of the control assembly to effectuate rotation of the distal tip. At least one working component of the catheter includes at least one channel component extending from a static portion disposed adjacent the proximal housing end in coupled and generally stationary relationship relative to the control case to a dynamic portion extending along and rotatable about the axis simultaneously with the catheter shaft. A lumen interruption mechanism is disposed in the control case and extends from a proximal mechanism end disposed in communication with the static portion of the at least one channel component to a distal mechanism end disposed in communication with the dynamic portion of said at least one channel component. As will be more fully explained in the following detailed description, the lumen interruption mechanism transitions the at least one channel component from the static portion to the dynamic portion as the at least one channel component translates through the housing compartment and is dynamically rotated about the axis simultaneously with the catheter shaft to maintain the integrity of the dynamic portion of the at least one channel component, and avoid damage such as via kinking, occlusion, or the like during use of the control assembly in a medical procedure.

Other aspects of the present disclosure will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:.

In the following description, details are set forth to provide an understanding of the present disclosure. In some instances, certain systems, structures and techniques have not been described or shown in detail in order not to obscure the disclosure.

Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, a control assembly <NUM> for a medical interventional device, such as a catheter, is generally shown. While the subject control assembly <NUM> is described herein for use with a catheter, it should be appreciated that the control assembly <NUM> could be used in association with other medical interventional devices without departing from the scope of the subject disclosure. As best illustrated in <FIG> and <FIG>, the catheter control assembly <NUM> includes a housing <NUM> which extends in a longitudinal direction along an axis A between a proximal housing end <NUM> and a distal housing end <NUM> to define a housing compartment <NUM> for receiving the catheter, along with at least one of its associated working components, namely a working channel component <NUM>, a fluid channel component <NUM>, and/or an electronics cable <NUM>.

More specifically, and as further illustrated in <FIG>, a control case <NUM> is disposed within the housing compartment <NUM> adjacent the proximal housing end <NUM>, and a catheter shaft <NUM> extends within the housing compartment <NUM> from the control case <NUM> and extending through and beyond the housing compartment to a distal tip <NUM> disposed adjacent and exterior to the distal housing end <NUM>. The working channel component <NUM> and the fluid channel component <NUM> of the catheter extend from respective static portions <NUM>', <NUM>' disposed adjacent the proximal housing end <NUM> in coupled and generally stationary relationship relative to the control case <NUM> and the housing <NUM> during operation of the control assembly <NUM>. For example, as best illustrated in <FIG> and <FIG>, a proximal case end <NUM> of the control case <NUM> includes a working channel port <NUM> and a fluid channel port <NUM>, each for receiving respective static portions <NUM>', <NUM>' of the working channel and fluid channel components <NUM>, <NUM> from an environment of the control assembly <NUM>. The electronics cable component <NUM> also extends from a static portion <NUM>' disposed in coupled and generally stationary relationship relative to the control case <NUM> and the housing <NUM> during operation of the control assembly <NUM>. For example, as also illustrated in <FIG>, the proximal case end <NUM> of the control case <NUM> can additionally include an electronics port <NUM> including a strain relief sheath <NUM> for receiving the static portion <NUM>' of the electronics cable <NUM> from the environment of the control assembly <NUM>. However, as illustrated in <FIG>, the electronics port <NUM> can also be disposed adjacent the distal case end <NUM> of the control case <NUM> such that the static portion <NUM>' of the electronics cable <NUM> enters the control case <NUM> and is coupled generally stationary relative to the distal case end <NUM> without departing from the scope of the subject disclosure.

Each of the static portions <NUM>', <NUM>', <NUM>' of the working channel component <NUM>, the fluid channel component <NUM> and the electronics cable <NUM> communicate with respective dynamic portions <NUM>", <NUM>", <NUM>" that extend along and are rotatable about the axis A simultaneously with the catheter shaft <NUM>. In other words, the catheter shaft <NUM> houses a dynamic portion <NUM>" of the working channel component <NUM>, a dynamic portion <NUM>" of the fluid channel component <NUM>, and a dynamic portion <NUM>" of the electronics cable <NUM> that pass through the catheter shaft <NUM> and break out at one or more locations adjacent or at the distal tip <NUM> of the catheter shaft <NUM>.

As noted previously, for a catheter shaft <NUM> that rotates during operation of the control assembly <NUM> in response to control by a user, it is problematic for the dynamic portions <NUM>", <NUM>", <NUM>" of the working channel, fluid channel and electronics cable components <NUM>, <NUM>, <NUM> (i.e., those portions of the working channel <NUM>, fluid channel <NUM> and electronics cable <NUM> passing through the compartment <NUM> of the housing <NUM> and along the catheter shaft <NUM>) to wind or overlap during rotation of the catheter shaft <NUM>. Torsional stresses and the crossing of the dynamic portions of these working components <NUM>, <NUM>, <NUM> during rotation can lead to damage or impair the function of the catheter. Accordingly, the control assembly <NUM> includes a lumen interruption mechanism <NUM> disposed adjacent the proximal housing end <NUM> of the control assembly <NUM> for transitioning the working components <NUM>, <NUM>, <NUM> from their static portions <NUM>', <NUM>', <NUM>' as they enter the control assembly <NUM> to their dynamic portions <NUM>", <NUM>", <NUM>" as they translate through the compartment <NUM> of the housing <NUM> and are dynamically rotated about the axis A simultaneously with the catheter shaft <NUM> to achieve rotational control of the distal tip <NUM> during a procedure.

As best illustrated in <FIG>, <FIG>and <FIG>, the lumen interruption mechanism <NUM> is disposed in the control case <NUM> adjacent the proximal case end <NUM> and extends from a proximal mechanism end <NUM> disposed in communication with the static portions <NUM>', <NUM>' of the working channel component <NUM> and the fluid channel component <NUM> to a distal mechanism end <NUM> disposed in communication with the dynamic portions <NUM>", <NUM>" of the working channel component <NUM> and the fluid channel component <NUM> for transitioning the working channel and fluid channel components <NUM>, <NUM> from their static to dynamic portions. The lumen interruption mechanism <NUM> includes a union reservoir cap <NUM> that is static (i.e., disposed in a generally fixed/non-movable condition) relative to the housing <NUM> of the control assembly <NUM> and a union reservoir hub <NUM> that is rotatably coupled to the union reservoir cap <NUM> and dynamically free to fully rotate about the axis A and relative to the union reservoir cap <NUM> within the control handle <NUM> and the control case <NUM>. As best illustrated in <FIG> and <FIG>, the union reservoir cap <NUM> includes a post <NUM> that mates with a corresponding portion of the control handle <NUM> to keep the union reservoir cap <NUM> from rotating about the axis A and maintain the union reservoir cap <NUM> in its static position. As also illustrated in <FIG>, in a preferred arrangement, the union reservoir cap <NUM> includes a pair of legs <NUM> that extend along an outer portion of the union reservoir hub <NUM> and terminate in a rotational channel <NUM> defined by the union reservoir hub <NUM> for rotatably coupling these two components together. However, other means of fixing the union reservoir cap <NUM> and establishing the rotatable coupling of the union reservoir cap and hub <NUM>, <NUM> could be utilized without departing from the scope of the subject disclosure.

As best illustrated in <FIG> and <FIG>, the union reservoir cap <NUM> defines a central cap inlet <NUM> and the union reservoir hub <NUM> defines a central hub outlet <NUM>. Each of the central cap inlet <NUM> and central hub outlet <NUM>, <NUM> extend through their respective components in aligned relationship with the axis A to dispose the inlet and outlet <NUM>, <NUM> in aligned, fluid communication with one another when the union reservoir cap and hub <NUM>, <NUM> are rotatably coupled together. With reference to <FIG>, the aligned central cap and hub inlet and outlet <NUM>, <NUM> define a fluid tight working channel, with a uniform ID that extends through the lumen interruption mechanism <NUM>. The union reservoir cap <NUM> also defines a cap fluid inlet <NUM> disposed in radially offset relationship with the axis A, extending in generally parallel relationship with the central cap inlet <NUM>. The union reservoir hub <NUM> defines a fluid reservoir <NUM> extending circumferentially about the central hub outlet <NUM> and disposed adjacent the central reservoir cap <NUM> in fluid communication with the cap fluid inlet <NUM>. As best illustrated in <FIG> and <FIG>, at least one sealing device <NUM>, such as an o-ring, gasket, gland or the like, is disposed between the union reservoir cap and hub <NUM>, <NUM> to seal the fluid reservoir <NUM>. A cap fluid outlet <NUM> extends in radially spaced and generally parallel relationship with the axis A from the fluid reservoir <NUM> to a bottom end <NUM> of the union reservoir hub <NUM>. Thus, as best illustrated in <FIG>, a fluid communication path is established through the rotatably coupled union reservoir cap and hub <NUM>, <NUM> sequentially via the cap fluid inlet <NUM>, the fluid reservoir <NUM>, and the cap fluid outlet <NUM>, with fluid communication maintained between the cap fluid inlet and outlets <NUM>, <NUM> even during rotation of the union reservoir hub <NUM> relative to the union reservoir cap <NUM> via the circumferntially-shaped fluid reservoir <NUM>.

As best illustrated in <FIG>, <FIG>and <FIG>, the dynamic portion <NUM>" of the working channel component <NUM> extending from at or adjacent the distal end <NUM> of the catheter shaft <NUM> terminates at the bottom end <NUM> of the union reservoir hub <NUM> and is coupled to the central hub outlet <NUM>. Similarly, the dynamic portion <NUM>" of the fluid channel component <NUM> extending from at or adjacent the distal tip <NUM> of the catheter shaft <NUM> terminates at the bottom end <NUM> of the union reservoir hub <NUM> and is coupled to the hub fluid outlet <NUM>. As further illustrated in <FIG> and <FIG>, the static portion <NUM>' of the working channel component <NUM> extends from the working channel port <NUM>, terminates at the union reservoir cap <NUM> and is coupled with the central cap inlet <NUM>. Similarly, the static portion <NUM>' of the fluid channel component <NUM> extends from the fluid channel port <NUM>, terminates at the union reservoir cap <NUM> and is coupled to the cap fluid inlet <NUM>.

In operation, and as will be explained in more detail below, rotation of the catheter shaft <NUM> to effectuate rotational movement of the distal tip <NUM>, such as via rotation of a rotation control knob <NUM> on the control assembly <NUM> by a user, simultaneously and synchronously drives rotation of the union reservoir hub <NUM> relative to the union reservoir cap <NUM>. As a result, the dynamic portions <NUM>", <NUM>" of the working and fluid channel components <NUM>, <NUM> which each extend from the union reservoir hub <NUM> to the distal tip <NUM> of the catheter shaft <NUM> rotate simultaneously and synchronously with one another and the catheter shaft <NUM>, while the static portions <NUM>', <NUM>' of the working and fluid channel components <NUM>, <NUM> which extend from the union reservoir cap <NUM> to their respective ports <NUM>, <NUM> remain in a static condition (notwithstanding rotational movement of the catheter shaft <NUM>). Thus, as illustrated in <FIG>, the lumen interruption mechanism <NUM> advantageously provides for a continuous ID working channel <NUM> that is static on the proximal mechanism end <NUM> of the lumen interruption mechanism <NUM> and torsionally dynamic on the distal mechanism end <NUM> of the lumen interruption mechanism <NUM>, while remaining fluid tight. The collective working channel, resulting from the combination of the static portion of the working channel <NUM>', the aligned central cup and hub inlet and outlet <NUM>, <NUM>, as well as the dynamic portion of the working channel <NUM>", also remains centrally aligned on the axis A even during rotation of the catheter shaft <NUM>. Furthermore, as illustrated in <FIG>, the lumen interruption mechanism <NUM> allows for the passage of fluid therethrough from the cap fluid inlet <NUM> to the cap fluid outlet <NUM> through a secondary off-axis fluid communication path that is independent of the central, aligned and collective working channel extending along the axis A. In this way, static inputs to the lumen interruption mechanism <NUM> are not adversely affected by rotational movement of the catheter shaft <NUM> and kinking/occlusion/damage of the dynamic portions <NUM>", <NUM>" of the working channel components extending from the lumen interruption mechanism <NUM> to the distal tip <NUM> of the catheter shaft <NUM> is avoided. The dynamic portion of the working channel <NUM>" and the dynamic portion of the fluid channel <NUM>" remain in their same relative positions to one another even while the catheter shaft <NUM> is being rotated about the axis A to effectuate rotation of the distal tip <NUM>. Thus, these working components <NUM>, <NUM> do not wind or overlap when the catheter shaft <NUM> is rotating, improving the functionality of the control assembly <NUM> relative to prior art devices.

As previously mentioned, rotation of the catheter shaft <NUM> to effectuate rotational movement of the distal tip <NUM> simultaneously and synchronously drives rotation of the union reservoir hub <NUM> relative to the union reservoir cap <NUM>. Synchronicity of these dynamic rotating mechanisms prevents winding and kinking of the various dynamic portions of the working components emanating from the union reservoir hub <NUM>. By all elements rotating as "one single body" relative to the remaining components that make up the control assembly <NUM>, winding damage within the control assembly <NUM> is negated. As will be described in more detail below with reference to <FIG>, <FIG> and <FIG>, this relationship is accomplished through the use of a synchronous rotation mechanism <NUM>.

As best illustrated in <FIG>, <FIG> and <FIG>, the control case <NUM> extends from the proximal case end <NUM> to a distal case end <NUM> to define a control compartment <NUM> extending therebetween. The lumen interruption mechanism <NUM> is preferably disposed in the control compartment <NUM> adjacent the proximal case end <NUM>. The control case <NUM> includes a center gear <NUM> disposed in the control compartment <NUM> adjacent the distal case end <NUM> in rotatably aligned relationship with the central axis A. As best illustrated in <FIG>, <FIG> and <FIG>, the catheter shaft <NUM> is secured or coupled to the center gear <NUM> for rotation therewith (as will be described in more detail below), and the center gear <NUM> defines a center gear passageway <NUM> extending along the axis A for allowing the dynamic portions of the working channel <NUM>, fluid channel <NUM> and electronic cable <NUM> which extend from the catheter shaft <NUM> to pass through the center gear passageway <NUM>, along the control compartment <NUM> and into their coupled positions with the union reservoir hub <NUM>.

The center gear <NUM> defines a set of center gear teeth <NUM> extending radially outwardly from the center gear <NUM> in circumferentially aligned relationship with the central axis A. A handle portion <NUM> surrounds the control case <NUM> and includes the rotation control knob <NUM> rotatably disposed about the distal case end <NUM> of the control case <NUM>. The rotation control knob <NUM> includes a set of rotation knob gear teeth <NUM> circumferentially arranged along an inner diameter of the rotation control knob <NUM>. The rotation control knob <NUM> is oriented on the control case <NUM> such that its axis of rotation remains constant relative to the control assembly <NUM> and its axial position also remains constant. At least one spur gear <NUM>, <NUM> is disposed between the rotation control knob <NUM> and the center gear <NUM> for disposing the rotation control knob <NUM> in operably coupled relationship with the set of center gear teeth <NUM> for driving rotation of the center gear <NUM> and the catheter shaft <NUM> in response to rotation of the rotation control knob <NUM> by a user.

For example, as best illustrated in <FIG> and <FIG>, the control assembly <NUM> can include a single, inner spur gear <NUM> for establishing the operable coupled relationship between the rotation control knob <NUM> and the center gear <NUM>. However, as best illustrated in <FIG>, the control assembly could include the inner spur gear <NUM> plus an additional, adjacent spur gear <NUM> which are sequentially disposed between the rotation control knob <NUM> and the center gear <NUM> to establish the operable interconnection therebetween. The use of the additional, adjacent spur gear <NUM> allows rotation of the rotation control knob <NUM> to distribute rotation of the center gear <NUM> in the same rotational direction.

More specifically, as illustrated in <FIG>, each of the inner spur gear <NUM> and the adjacent spur gear <NUM> are disposed radially inward from the rotation control knob <NUM> such that their respective axis of rotation are aligned with one another, as well as the central axis A, in parallel (but radially spaced) relationship. As a result, the rotation knob gear teeth <NUM> are disposed in operable connection with the inner spur gear <NUM>, which is disposed in operable connection with the adjacent spur gear <NUM>, which is in operable connection with the center gear <NUM> to drive rotation of the catheter shaft <NUM> about the axis A in the same direction as the rotational direction of the rotation control knob <NUM>. The diameters of this power train are designed to a desired output ratio.

The synchronous rotation mechanism <NUM> is disposed in operably coupled relationship with the union reservoir hub <NUM> of the lumen interruption mechanism <NUM> and the center gear <NUM> to simultaneously and synchronously drive rotation of the union reservoir hub <NUM> in response to rotation of the center gear <NUM> (and the catheter shaft <NUM> coupled thereto) via the rotation control knob <NUM>. As best illustrated in <FIG>, <FIG> and <FIG>, the synchronous rotation mechanism <NUM> includes an axle <NUM> extending from a proximal axle end <NUM> operably coupled with the union reservoir hub <NUM> to a distal axle end <NUM> operably coupled with the center gear <NUM>. The axle <NUM> is rotatable in response to rotation of the center gear <NUM> to establish the synchronous rotation of the union reservoir hub <NUM>.

More specifically, as best illustrated in <FIG>, <FIG> and <FIG>, in accordance with a first embodiment of the synchronous rotation mechanism <NUM>, the axle <NUM> extends within the control compartment <NUM> in aligned relationship with the axis A such that the proximal axle end <NUM> is directly connected to the union reservoir hub <NUM> and the distal axle end <NUM> is directly connected to the center gear <NUM>. In this arrangement, rotation of the center gear <NUM> by the rotation control knob <NUM> results in a direct drive of the union reservoir hub <NUM> via the axle <NUM>. The direct drive axle <NUM> is preferably comprised of a rigid tubular structure strong enough to distribute torque from the center gear <NUM> to which it is attached distally to the union reservoir hub <NUM> to which it is attached proximally. As will be appreciated in view of the second embodiment of the synchronous rotation mechanism <NUM>, use of the direct drive axle <NUM> simplifies a structure of the synchronous rotation mechanism <NUM> through use of a single component as opposed to requiring multiple components to establish synchronous rotation of the union reservoir hub <NUM> with the center gear <NUM>. As further illustrated in <FIG> and <NUM>, the arrangement of the tubular-shaped axle <NUM> along the axis A also allows the working channel <NUM>, the fluid channel <NUM>, and/or the electronics cable <NUM> to pass through the axle <NUM>. More specifically, the axle <NUM> defines an internal component passageway <NUM> extending between the proximal and distal axle end <NUM>, <NUM>, such that the dynamic portions <NUM>", <NUM>" of the working and fluid channel components <NUM>, <NUM> can extend from their respective hub outlets <NUM>, <NUM>, pass through the internal component passageway <NUM> and into the catheter shaft <NUM> (which is coupled to the center gear <NUM>). As will be described in more detail below, in an arrangement, the dynamic portion <NUM>' of the electronics cable <NUM> could also pass from the lumen interruption mechanism <NUM> and into the internal component passageway <NUM> for routing to the catheter shaft <NUM>. As further illustrated in <FIG>, the proximal axle end <NUM> of the axle <NUM> in the first embodiment of the synchronous rotation mechanism <NUM> can include a castellation feature <NUM> for establishing a mechanical interface and torque distribution to the union reservoir hub <NUM> via the direct connection. The distal axle end <NUM> of the axle can also include a breakout slot <NUM> for allowing any of the working components to break out of the interior component passageway <NUM> as needed to make their connections to the complementary components of the control assembly <NUM>.

As best illustrated in <FIG>, in accordance with a second embodiment of the synchronous rotation mechanism <NUM>, the proximal and distal axle ends <NUM>, <NUM> of the axle <NUM> are indirectly connected to the union reservoir hub <NUM> and center gear <NUM>, respectively. More specifically, in this second embodiment of the synchronous rotation mechanism <NUM>, the union reservoir hub <NUM> defines a set of hub gear teeth <NUM> extending radially outwardly from the union reservoir hub <NUM> in circumferentially aligned relationship about the central axis A. The synchronous rotation mechanism <NUM> includes a proximal spur gear <NUM> disposed on the proximal axle end <NUM> of the axle <NUM>, radially outward from the union reservoir hub <NUM> and in operable engagement with the hub gear teeth <NUM>. The distal axle end <NUM> of the axle <NUM> is connected to the adjacent spur gear <NUM> that is operably interconnected with the center gear <NUM>, which is used to drive rotation of the center gear <NUM> via rotation of the rotation control knob <NUM> in accordance with an arrangement, as previously described. The proximal spur gear <NUM> is rotatable by the axle <NUM> about an axis of rotation that is parallel and radially spaced with the central axis A, and axially aligned with the axis of rotation of the adjacent spur gear <NUM>. Put another way, the proximal spur gear <NUM> and the adjacent spur gear <NUM> are disposed in axially aligned relationship for rotation about a shared axis of rotation. The axle <NUM> extends axially between the adjacent spur gear <NUM> and the proximal spur gear <NUM> along this shared axis of rotation to synchronously and simultaneously drive rotation of the proximal spur gear <NUM> via rotation of the adjacent spur gear <NUM> driven by the rotation control knob <NUM>. The proximal spur gear <NUM> is configured to have the same design and radial orientation as the adjacent spur gear <NUM> to result in simultaneous equivalent rotation. The hub gear teeth <NUM> of the union reservoir hub <NUM> are also identical in size, number and diameter to the center gear teeth of the center gear <NUM>. In this way, rotation of the center gear <NUM> results in <NUM>: <NUM> rotation of the union reservoir hub <NUM> and therefore the catheter shaft <NUM> connected to the center gear <NUM> and the working components coupled to the union reservoir hub <NUM> move in synchronicity in response to rotation of the rotation control knob <NUM> by a user of the control assembly <NUM>.

Similar to the winding and overlapping problem discussed immediately above with respect to the dynamic portions of the working and fluid channels <NUM>", <NUM>", torsion and kinking of the at least one electronics cable <NUM> during rotation of the catheter shaft <NUM> can also lead to failure and compromised performance of this working component. Accordingly, the control assembly <NUM> also includes a cable take-up assembly <NUM> configured to enable rotation of the catheter shaft <NUM> without adversely winding the electronics cable <NUM> and without the additional requirement of a joint and connectors along the electronics cable <NUM> to achieve this objective, namely because different from the working and fluid channels <NUM>, <NUM>, it is often not practical to interrupt or bifurcate the wires within the electronics cable <NUM>. As best illustrated in <FIG> and <FIG>, the cable take-up assembly <NUM> is disposed in the control compartment <NUM> of the control case <NUM> and is rotatable about the axis A synchronously with the union reservoir hub <NUM> and the center gear <NUM>. The cable take-up assembly <NUM> defines a spool <NUM> extending circumferentially about the axis A, and the electronics cable <NUM> is routed to and around the spool <NUM> between the static portion <NUM>' and the dynamic portion <NUM>". As illustrated in <FIG> and <FIG>, and described in more detail below, synchronous rotation of the cable take-up assembly <NUM> with the union reservoir hub <NUM> and the center gear <NUM> in a first rotational direction winds the electronics cable <NUM> around the spool <NUM> and synchronous rotation of the cable take-up assembly <NUM> in a second opposite rotational direction unwinds the electronics cable <NUM> from the spool <NUM> for allowing the dynamic portion <NUM>" of the electronics cable <NUM> which passes from the cable take-up assembly <NUM> to the distal tip <NUM> of the catheter shaft <NUM> to maintain a position relative to the dynamic portions of the working and fluid channel components <NUM>", <NUM>" during their collective, simultaneous rotation with the catheter shaft <NUM>. As illustrated in <FIG>and <FIG>, in accordance with a first embodiment, the cable take-up assembly <NUM> can be implemented as an integrated component of the lumen interruption mechanism <NUM>, and thus a combined functionality component. However, as best illustrated in <FIG> and <FIG>, in accordance with a second embodiment, the cable take-up assembly <NUM> could also be a separate component located elsewhere within the control assembly <NUM> from the lumen interruption mechanism <NUM>, in this case on the center gear <NUM>. This is because in practice the functionality of the cable-take-up assembly <NUM> is independent of the lumen interruption mechanism <NUM> (other than the rotational synchronicity) and can exist as a separate component(s) in similar applications.

As best illustrated in <FIG>, in the first embodiment of the cable take-up assembly <NUM>, the spool <NUM> is defined by the union reservoir hub <NUM> and extends radially inwardly from an exterior surface of the union reservoir hub <NUM> and circumferentially about the axis A. A spool slack chamber <NUM> is defined between an interior surface of the spool <NUM> (as defined by an inner diameter of the union reservoir hub <NUM>) and an interior surface of the control assembly <NUM>, disposed adjacent the cable take-up assembly <NUM>. As will be understood in view of the following discussion of operation, the interior surface of the control assembly <NUM> used to define an exterior wall of the slack chamber <NUM> provides a barrier to limit the build-up of excessive slack in the slack chamber <NUM> during rotation of the spool <NUM>. The spool <NUM> defines a window <NUM> disposed in both communication with this slack chamber <NUM> as well as an electronics cable passage <NUM> that extends from the lumen interruption mechanism <NUM> to the electronics port <NUM>. The electronics cable <NUM> is routed such that a distal length extends from the distal tip <NUM> of the catheter shaft <NUM> to the union reservoir hub <NUM> of the lumen interruption mechanism <NUM>, with a medial length of the electronics cable <NUM> then wound loosely around the spool <NUM> a predetermined number of times such that the wound electronics cable <NUM> is housed within the spool slack chamber <NUM>. A proximal length of the electronics cable <NUM> then continues from the slack chamber <NUM>, through the window <NUM> and extends through the electronics cable passage <NUM> to be routed through the strain relief <NUM> and ultimately be affixed to a static PCB. As will be explained above, use of the cable take-up assembly <NUM> provides for the distal length of the electronics cable <NUM> to rotate in unison with the catheter shaft <NUM> such that the electronics cable <NUM> never winds around other working components, such as the dynamic working and fluid channels <NUM>, <NUM>. In addition, the cable take-up assembly <NUM> advantageously allows for the use of one, continuous electronics cable <NUM> extending through the control assembly <NUM>, without the need for electrical connectors.

As best illustrated in <FIG>, in operation, rotation of the cable take-up assembly <NUM> in one direction (in this case synchronously with rotation of the union reservoir hub <NUM>) takes up the slack in the spool <NUM> to facilitate safe rotation of the catheter shaft <NUM>, while rotation of the cable take-up assembly <NUM> in the other direction (again synchronously with corresponding rotation of the union reservoir hub <NUM>) unwinds and loosens the loops of the electronics cable <NUM> around the spool <NUM>. As the cable take-up assembly <NUM> rotates, the window <NUM> acts to guide the electronics cable <NUM> around the spool <NUM>. Put another way, the window <NUM> acts like an eyelet, forcing the electronics cable <NUM> to rotate in association with the union reservoir hub <NUM>. The number of cable winds corresponds to the amount of limitation required by the control assembly <NUM>, which can be greater than <NUM> degrees if necessary, but not practically infinite. As a result, the cable take-up assembly <NUM> minimizes the torque and winding condition on the electronics cable <NUM> breaking out from the catheter shaft <NUM> and which otherwise would occur during rotation of the catheter shaft <NUM>.

As mentioned previously, in accordance with a second embodiment, the cable take-up assembly <NUM> is implemented on the center gear <NUM> as opposed to on the lumen interruption mechanism <NUM>. (See <FIG> and <FIG>). In regards to the electronics cable, there are many types of electronics cables that might be used in the control assembly <NUM>. Some electronics cables are more resistant to bending, some are more prone to kink, some are more supple and less inclined to react predictably to "push forces", etc. In instances where the mechanical characteristics of the electronics cable do not lend themselves as favorable to the unwinding action described above, particular failure modes might occur. This can manifest in the clockwise (first rotational direction) and counterclockwise (second rotational direction) of the cable take-up assembly <NUM>, with the back and forth of the electronics cable in tension followed by compression (push) resulting in knotting and accumulation of the electronics cable within the spool <NUM>. The end effect can be a loss of degradation of image signal due to the knotting, to worst case scenario of the knotting decreasing the total free length of the cable and resulting in fracture of the electronics cable and full loss of function of the electronics.

As best illustrated in <FIG>, the control assembly <NUM> implements a solution to this problem, namely routing the static portion <NUM>' of the electronics cable <NUM> through a cable tensioning mechanism <NUM> prior to the spool <NUM> to continually apply a small amount of tension to the electronics cable <NUM> regardless of the rotational direction of the spool <NUM> and always maintain the electronics cable <NUM> taught against an inner diameter of the spool <NUM>, in all instances. In other words, the cable tensioning mechanism <NUM> keeps the electronic cable <NUM> in tension with the spool <NUM>, and prevents the "push" phase of rotation of the spool <NUM> from bringing in the variability that might result in knotting.

More specifically, as best illustrated in <FIG>, the control case <NUM> defines a tensioning channel <NUM> extending in generally parallel and radially spaced relationship with the axis A between the proximal and distal case ends <NUM>, <NUM>. When the static portion <NUM>' of the electronics cable <NUM> enters the control case <NUM> via the distal case end <NUM>, the tensioning channel <NUM> is disposed in communication with the electronics port <NUM> and extends from the distal case end <NUM> towards the proximal case end <NUM>. However, the directional arrangement of the tensioning channel <NUM> could be reversed, and extend from the proximal case end <NUM>, if the electronics cable <NUM> entered the control case <NUM> via an electronics port <NUM> disposed at the proximal case end <NUM> (such as shown in <FIG>). The cable tensioning mechanism <NUM> is disposed in the tensioning channel <NUM> and includes a loop component <NUM> biased away from the electronics port <NUM> (in this case towards the proximal case end <NUM>) and in a direction away from where the static portion <NUM>' of the electronics cable <NUM> enters the control case <NUM>. As best illustrated in <FIG>, the loop component <NUM> defines a radiused portion <NUM>, such that the static portion <NUM>' of the electronics cable <NUM> is routed from the electronics port <NUM> through the tensioning channel <NUM> and to the loop component <NUM> at which point the electronics cable <NUM> passes over the radiused portion <NUM> to redirect the electronics cable from one direction to another and back along the tensioning channel <NUM> for routing to the spool <NUM>. As best illustrated in <FIG>, when the electronics cable <NUM> is routed back adjacent the spool <NUM>, the electronics cable <NUM> passes around a shoulder <NUM> to assist in redirecting the electronics cable <NUM> transversely from the tensioning channel <NUM> and towards the spool <NUM>.

As illustrated in <FIG>, the radiused portion <NUM> of the loop compartment <NUM> is preferably <NUM> degrees, to establish that most practical re-direction of force application. However, this redirection of the electronics cable path could be any angle off the major axis to apply a tensile load, but is most effective for direction changes greater than <NUM> degrees and up to but not including an angle that would put the electronics cable back in line with its major axis, i.e., <NUM> degrees. The design of this loop component <NUM> is such that the electronics cable <NUM> can be installed without the need to pass both ends of the electronics cable <NUM> through the radiused portion <NUM>, i.e., the electronics cable <NUM> can be affixed to the loop component <NUM> anywhere mid-section of the electronics cable <NUM>.

As further illustrated in <FIG>, the tensioning mechanism <NUM> includes a biasing member <NUM>, such as a spring, or the like, extending between the control case <NUM> and the loop component <NUM> to establish the biased relationship away from the electronics port <NUM>, and apply a counter force to the loop component <NUM> in movement and therefore to the electronics cable <NUM> routed around the radiused portion <NUM>. If the biasing member <NUM> is a tension spring, the tension spring is attached to the loop component <NUM> above the radiused portion <NUM> (such as shown in <FIG>). However, if the biasing member <NUM> is a compression spring, the compression spring would be attached below the radiused portion <NUM>, without departing from the scope of the subject disclosure.

As illustrated in <FIG>, during operation, rotation of the cable take-up assembly <NUM> and the associated spool <NUM> in a first rotational direction (as shown in <FIG>) winds the electronics cable <NUM> around the spool <NUM>, foreshortening a length between the spool <NUM> and the loop component <NUM> and causing the loop component <NUM> to be displaced along the tensioning channel <NUM> in a direction towards the spool <NUM>. This displacement is resisted by the biasing member <NUM> and a tensile force is distributed to the electronics cable <NUM>, such that the electronics cable <NUM> is never allowed to have enough slack to entangle or knot. As shown in <FIG>, changing direction of rotation of the cable take-up assembly <NUM> and the associated spool <NUM> in the opposite rotational direction un-wraps the electronic cable <NUM> from the spool <NUM> and results in the loop component <NUM> moving in the opposite linear direction (via the biasing force applied by the biasing member <NUM>), reducing the tensile force applied to the electronics cable <NUM>. As the spool <NUM> passes over center, the direction of the wrap around the spool <NUM> changes while the loop component <NUM> repeats its linear cycle applying the tensile load. In this way, as the cable take-up assembly <NUM> cycles through the full range of rotation, the loop component <NUM> cycles up and down, like a piston, continually applying a tensile load to the electronics cable <NUM> to always keep the electronics cable <NUM> taught against the spool <NUM> and prevent entanglement and knotting.

As illustrated in <FIG> and <FIG>, the handle <NUM> of the control assembly <NUM> also includes a deflection control knob <NUM> rotatably disposed about the proximal case end <NUM> of the control case <NUM> to effectuate deflection of the distal tip <NUM> of the catheter shaft <NUM> in response to rotation of the deflection control knob <NUM> by the user. As best illustrated in <FIG>, <FIG> and <FIG>, the control case <NUM> includes an anchor arm <NUM> disposed within the control compartment <NUM> adjacent a proximal end of the center gear <NUM> and having an anchor shaft <NUM> extending axially downwardly into the center gear passageway <NUM>. At least one pull wire <NUM> extends from the anchor arm <NUM> into the catheter shaft <NUM> and ultimately terminates at the distal tip <NUM>. As best illustrated in <FIG> and <FIG>, a pull wire tensioning mechanism <NUM> is provided for fixing the pull wire <NUM> to the anchor arm <NUM>, and allowing an operator to modify a length of the pull wire <NUM> between the anchor arm <NUM> and the distal tip <NUM> in order to provide a base tension of the pull wire <NUM> that correlates with a desired adjustment sensitivity of the pull wire. A preferred arrangement of the pull wire tensioning mechanism <NUM> is described in <CIT>, such as in Paragraph [<NUM>].

As best illustrated in <FIG>, <FIG>, the anchor shaft <NUM> defines at least one axial rib <NUM> extending radially outwardly from the anchor shaft <NUM> in aligned and radially spaced relationship with the central axis A. The center gear <NUM> defines at least one axial slot <NUM> extending radially inwardly from the center gear passageway <NUM> for receiving the at least one axial rib <NUM>. Mating of the axial rib <NUM> with the axial slot <NUM> drives synchronous and simultaneous rotation of the anchor arm and shaft <NUM>, <NUM> with the center gear <NUM>, and also allows the anchor arm and shaft <NUM>, <NUM> to translate proximally and distally relative to center gear <NUM> (as will be described in more detail below, and best illustrated in <FIG>) while still maintaining rotational alignment between these components. As a result, the mating of the axial rib <NUM> with the axial slot <NUM> allows the anchor arm <NUM> to work in concert with the center gear <NUM> as well as the synchronous rotation mechanism <NUM> in such a way that the pull wire <NUM> maintains radial orientation with the catheter shaft <NUM>, and is not buckled, kinked, or overlapped with the other working components during rotation of the catheter shaft <NUM> by the user via rotation of the rotation control knob <NUM>.

As illustrated in <FIG>, the anchor arm <NUM> and anchor shaft <NUM> collectively define an anchor passageway <NUM> disposed in communication with the center gear passageway <NUM> for allowing the dynamic portions of the working components of the catheter to be received from the center gear passageway <NUM> and pass through the anchor passageway <NUM> into the control compartment <NUM>. The control case <NUM> includes a lead screw <NUM> disposed within the control compartment <NUM> adj acent to a proximal end of the anchor arm <NUM> and having a rotor flange <NUM> disposed in coupled relationship with a circumferential slot <NUM> defined by an interior portion of the anchor arm <NUM> and which extends radially inward from the anchor passageway <NUM>. (See <FIG>). As will be appreciated in view of the following description, this joint holds the lead screw <NUM> and the anchor arm <NUM> together axially while also allowing full rotation of the anchor arm relative to the lead screw <NUM> (which is always maintained in a rotationally static position). As best illustrated in <FIG>, similar to the center gear <NUM> and the anchor arm <NUM>, the lead screw <NUM> also defines a lead screw passageway <NUM> that allows the dynamic portions of the working components of the catheter to pass along from the anchor passageway <NUM> towards the union reservoir hub <NUM> disposed proximally above.

As best illustrated in <FIG>, <FIG>, <FIG> and <FIG>, the control case <NUM> includes a threaded gear <NUM> disposed in rotationally aligned relationship about the central axis A and including an internal thread <NUM> disposed in threaded relationship with a proximal end of the lead screw <NUM>. A set of threaded gear teeth <NUM> extend radially outwardly from the threaded gear <NUM>, and at least one deflection spur gear <NUM>, <NUM> is disposed in the control compartment <NUM> to establish the operably coupled relationship between the deflection control knob <NUM> and the threaded gear <NUM>. For example, as illustrated in <FIG>, in accordance with a first arrangement, only a first deflection spur gear <NUM> is arranged in radially offset relationship from and in operable relationship with both the threaded gear teeth <NUM> of the threaded gear <NUM> and the deflection control knob <NUM> to establish the operable coupling therewith. However, as best illustrated in <FIG> and <FIG>, in accordance with a second arrangement, an additional second deflection spur gear <NUM> can be sequentially arranged in radially offset relationship to the threaded gear <NUM>. Put another way, as best illustrated in <FIG>, the first deflection spur gear <NUM> is disposed radially offset from and in operable relationship with the threated gear teeth <NUM> of the threaded gear <NUM>, and the second deflection spur gear <NUM> is disposed radially offset from an in operable relationship with the first deflection spur gear <NUM>, such that rotation of the second (most radially offset) deflection spur gear <NUM> ultimately drives rotation of threaded gear <NUM>. As previously mentioned, the handle <NUM> of the control assembly <NUM> also includes a deflection control knob <NUM> rotatably disposed about the proximal case end <NUM> of the control case <NUM>. As best illustrated in <FIG>, this deflection control knob <NUM> includes a set of deflection knob gear teeth <NUM> circumferentially arranged along an inner diameter of the deflection control knob <NUM> and which are operably coupled with the first deflection spur gear <NUM> (in the first arrangement) or the second deflection spur gear <NUM> (in the second arrangement).

As best illustrated sequentially in <FIG>, in operation, rotation of the deflection control knob <NUM> ultimately drives rotation of the threaded gear <NUM>, which is disposed in engaging relationship with the thread of the lead screw <NUM>, resulting in axial displacement of the lead screw <NUM> both proximally and distally (depending on the rotational direction of the deflection control knob <NUM>). When the lead screw <NUM> is axially displaced in the proximal direction (as shown in <FIG>), the anchor arm <NUM> is also axially displaced over the same distance by way of the coupling between the rotor flange <NUM> of the lead screw <NUM> and the circumferential slot <NUM> of the anchor arm <NUM>, such that a resultant tension is applied to the pull wire <NUM> secured to the anchor arm <NUM> by way of this pulling motion. Thus, this axial displacement of the lead screw <NUM> over a distance effectuates the desired distal deflection curve in the distal tip <NUM> of the catheter shaft <NUM>. For clarity, and as previously mentioned, the mating of the axial ribs and slot <NUM>, <NUM> allows for axial movement of the anchor arm <NUM> relative to the center gear <NUM> and in conjunction with the lead screw <NUM> to effectuate the desired deflection.

As best illustrated in <FIG>, <FIG>, <FIG>, <FIG> and <FIG>, the lead screw <NUM> includes an anti-torque wing <NUM> extending radially outwardly from the lead screw <NUM> and disposed in engaging relationship with a corresponding wing slot <NUM> disposed adjacent the lead screw <NUM> and defined by the control case <NUM> to prevent the lead screw <NUM> from rotating in response to movement by the threaded gear <NUM>, and limit movement of the lead screw <NUM> to only the up (proximal) and down (distal) directions. As a result, torque is not distributed down to the pull wire to further prevent the pull wire from wrapping around other working components of the catheter. A pitch of the lead screw <NUM> and a pitch of the internal thread <NUM> of the threaded gear <NUM> is such that the friction angle remains intact, allowing the lead screw <NUM> to stay in place static when the deflection control knob <NUM> is not manipulated by a user.

As best illustrated in <FIG>, the control case <NUM> (which is surrounded by the handle <NUM>) is axially translatable along the housing <NUM> from the proximal housing end <NUM> towards the distal housing end <NUM> to effectuate advancement and retraction of the catheter shaft <NUM>, namely because the catheter shaft <NUM> is affixed to the center gear <NUM> and travels with the control case <NUM> during axial movement. As the control case <NUM> travels towards the distal housing end <NUM> of the housing <NUM>, the distal tip <NUM> of the catheter shaft <NUM> is axially advanced by the user by way of translating the control case <NUM>. However, during movement of the control case <NUM>, a length of the catheter shaft <NUM> extending between the center gear <NUM> and the distal end <NUM> of the housing <NUM> is inclined to buckle, bend, and/or kink when a compressive load is applied to this length of catheter shaft <NUM>, such as when the handle <NUM> is translated along the housing <NUM> by the user. The catheter shaft <NUM> has an amount of column strength by design to resist buckling and kinking, however the longer the distance between two points of support, the more side loading due to gravity, angular position of the catheter, user manipulation, etc. is inclined to move the catheter shaft <NUM> off its central axis A and decrease/defeat column strength.

The control assembly <NUM> includes a proportional support mechanism <NUM> disposed within the housing compartment <NUM> and continuously supporting the catheter shaft <NUM> at a point between the center gear <NUM> and the distal housing end <NUM> during the axial advancement of the catheter shaft <NUM> to provide additional point(s) of support consistently maintained along the length of catheter shaft <NUM> extending between the center gear <NUM> and the distal end <NUM> of the housing <NUM> across the entire range of travel of the control case <NUM> relative to the housing <NUM>. Put another way, as the control case <NUM> moves towards the distal end <NUM> of the housing <NUM> to axially advance the distal tip <NUM> of the catheter shaft <NUM> in the distal direction, the proportional support mechanism <NUM> moves proportional to this displacement and continuously supports the catheter shaft <NUM> at a point(s) between the center gear <NUM> and the distal end <NUM> of the housing <NUM> to prevent the catheter shaft <NUM> from buckling and/or kinking. In a preferred arrangement, the proportional support mechanism <NUM> continuously supports the catheter shaft <NUM> at a midpoint between the center gear <NUM> and the distal housing end <NUM>. However, other points along the catheter shaft <NUM> could be utilized without departing from the scope of the subject disclosure.

As best illustrated in <FIG>, the proportional support mechanism <NUM> includes a gear boss <NUM> extending radially outwardly from a distal case end <NUM> of the control case <NUM> and a reduction gear <NUM> having both a major gear feature <NUM> and a minor gear feature <NUM> is rotatably disposed on the gear boss <NUM>. A catheter support arm <NUM> extends within the compartment <NUM> of the housing <NUM> from a first support arm end <NUM> operably coupled with the minor gear feature <NUM> of the reduction gear <NUM> to a second support arm end <NUM> disposed in spaced relationship with the distal end <NUM> of the housing <NUM>. A catheter support platform <NUM> extends radially from the second support arm end <NUM> and defines a cathether lumen <NUM> through which the catheter shaft <NUM> passes as it extends between the center gear <NUM> and the distal end <NUM> of the housing <NUM>. The catheter support arm <NUM> defines a minor gear rack <NUM> extending between the first and second support arm ends <NUM>, <NUM>, and which is operably coupled with the minor gear feature of the reduction gear <NUM>. The housing <NUM> also defines a major gear rack <NUM> operably coupled with the major gear feature <NUM> of the reduction gear <NUM>. The major gear rack <NUM> extends from a starting position radially adjacent to the reduction gear <NUM> when the control case <NUM> is disposed adjacent the proximal housing end <NUM> to an ending position disposed adjacent the distal housing end <NUM>.

In operation, since the reduction gear <NUM> is attached to an axle on the control case <NUM>, namely the gear boss <NUM>, linear manipulation of the control case <NUM> results in rotational engagement of the reduction gear <NUM> to its mating major and minor gear racks <NUM>, <NUM>. The ratio of translated linear motion between the major and minor gear racks <NUM>, <NUM> results in placement of the catheter support platform <NUM> of the catheter support arm <NUM> at a central position of the exposed catheter shaft <NUM>. Put another way, with reference to <FIG>, as the control case <NUM> is moved towards the distal housing end <NUM> of the housing <NUM>, the reductive gear system provided by the reduction gear <NUM> and the major and minor gear racks <NUM>, <NUM> maintains a distance between the catheter support platform <NUM> and the center gear <NUM> (Distance A) and a distance between the catheter support arm <NUM> and the distal housing end <NUM> of the housing <NUM> (Distance B) which are always equal. This is because the reduction gear system results in a reduced rate of axial movement of the catheter support arm <NUM> relative to the control case <NUM>. In this way, the unsupported lengths of the shaft (Distances A and B) are always half that of the total unsupported length (A + B), promoting column strength by 2X and decreasing the effects of side loading that would otherwise induce buckling and kinking failures. It is understood that this mechanism may be duplicated within an embodiment of the catheter control assembly whereby a plurality of catheter support arms <NUM>, each with their own reduction gears with specific minor and major gear diameters and associated racks, could be employed to support the catheter shaft at thirds, quarters, etc. in order to best minimize the risk of kinking and buckling over a given catheter length.

Claim 1:
A control assembly (<NUM>) for a catheter having at least one working component (<NUM>, <NUM>, <NUM>), the control assembly (<NUM>) comprising:
a housing (<NUM>) extending along an axis (A) between a proximal housing end (<NUM>) and a distal housing end (<NUM>) to define a housing compartment (<NUM>) therebetween;
a control case (<NUM>) disposed within said housing compartment (<NUM>) adjacent said proximal housing end;
a catheter shaft (<NUM>) extending within said housing compartment from said control case to a distal tip (<NUM>) and rotatable about the axis during operation of the control assembly;
at least one channel component (<NUM>, <NUM>) of the catheter extending from a static portion (<NUM>', <NUM>') disposed adjacent said proximal housing end (<NUM>) in coupled and stationary relationship relative to said control case (<NUM>) to a dynamic portion (<NUM>", <NUM>") extending along and rotatable about the axis (A) simultaneously with said catheter shaft (<NUM>); and
a lumen interruption mechanism (<NUM>) disposed in said control case (<NUM>) and extending from a proximal mechanism end (<NUM>) disposed in communication with said static portion (<NUM>', <NUM>') of said at least one channel component (<NUM>, <NUM>) to a distal mechanism end (<NUM>) disposed in communication with said dynamic portion (<NUM>", <NUM>") of said at least one channel component (<NUM>, <NUM>) for transitioning said at least one channel component (<NUM>, <NUM>) from said static portion (<NUM>', <NUM>') to said dynamic portion (<NUM>", <NUM>").