Various embodiments relate generally to construction of minimally invasive catheters, including, for example, steerable catheters.
Apparatus and associated methods relate to a flexible extrusion having a number of radially extending members configured for slidable insertion into a lumen of a surgical catheter shaft. In an illustrative example, the extrusion may have a flexible wall and define an interior insert lumen extending along the longitudinal axis from a proximal end to a distal end. Each of the radially extending members may have a distal engaging surface. When the extrusion is slidably inserted, for example, into the lumen of the catheter shaft, the distal engaging surface of each of the plurality of radial extending members may slidably engage an interior surface of the catheter shaft. In some examples, the inserted extrusion may define an annular distribution of longitudinally extending channels between a proximal and a distal end of the catheter. The slidable construction may advantageously simplify assembly, for example. The channels may offer end-to-end communication.
Various embodiments may achieve one or more advantages. For example, some embodiments may be advantageously assembled at a reduced labor, time, and expense by sliding the insert into the outer sheath. One or more conventional assembly steps may be reduced or eliminated in a catheter construction process. In operation, the catheter can employ the channels for an array of functional filaments or to communicate flowable media between the opposing ends of the catheter, for example. Various embodiments may further be capable of being partially assembled with the MCCI insert and preloaded with one or more steering wire sets, for example. In some embodiments, partially assembled MCCI assemblies may be stored in inventory, and subsequently customized by outfitting with selected filaments or, in operation, communicating selected media, as needed for custom surgical applications, for example.
The details of various embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
The channels 155a-155d, when slidably engaged with an inner surface 150, define tangentially distributed, isolated channels that run longitudinally along the length of the shaft 120.
Within one or more of these channels 155a-155d, one or more functional filaments may be employed. The functional filaments may include, for example, one or more distal tip steering wires, electrical wires, or fiber optics. The steering wires may be constructed of, for example, polymer or a non-reactive metal. In the depicted
Moving clockwise, an adjacent one of the channels 155a-155d includes a steering pull wire, which may be secured, for example, to a distal end of the shaft 120. The pull wire may be tensioned from a proximal end, for example with the handle 115, to deflect the tip such that, in combination with any needed rotation, may be used to position the distal tip in a required orientation (e.g., for steering, to deliver a therapy, for diagnostic sensing).
Moving clockwise again, an adjacent one of the channels 155a-155d includes an optical fiber. In some examples, one or more optical fibers may be used to direct light signals to or from the distal tip (e.g., to deliver therapy, for illumination, for optical visualization).
Moving clockwise once again, an adjacent one of the channels 155a-155d includes a flowable media, e.g. a cooling gas, that can be communicated between the proximal and distal ends of the shaft 120. In some implementations, one or more of the channels 155a-155d may provide a substantially sealed passageway suitable to convey flowable media (e.g., low pressure gasses) between the opposing ends of the shaft 120.
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The exemplary configurations in the cross-sectional and perspective views of
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In some embodiments, the various wires may be threaded and the various wires may not be fixed or fused to any portion of an insert or of an outer sheath, thereby advantageously decreasing the cost, labor, and time for constructing and employing these embodiments. In some embodiments, the various wires may be fixed or fused to various points of an insert or at various points along an outer sheath, advantageously increasing functionality. The various wires may be fixed or fused to various points employing, for example, lasers, heat, or magnets. In the depicted embodiments in
In some embodiments, as depicted in
In some embodiments, an insert wall or an insert ring may be constructed of or supported by various helically wound coils. An insert wall or an insert ring supported by various helically wound coils may be a separate construction with which an inner insert wall or an inner insert ring wall slidably engages. An insert wall or an insert ring supported by various helically wound coils may be pre-installed for advantageous construction of a catheter employing multiple functions. In some embodiments, an insert wall may be constructed of various helically wound coils. An insert wall or an insert ring constructed of or supported by various helically wound coils may have advantageous steerability and rigidity features.
Although various embodiments have been described with reference to the Figures, other embodiments are possible. For example, one or more of the channels may have available space for providing additional functionality in addition to steering of the distal end. Various implementations my use available channels for delivering and/or withdrawing (e.g., aspiration) materials, energy, and/or signals between the distal and proximal ends of the catheter.
Referring to
In some embodiments, the functional filaments may be threaded through the channels 155a-155d after insertion of insert 135 into the outer sheath 130 to form the catheter 110.
In some embodiments, inserting a filament in one of the available channels after the MCCI has been inserted into the outer sheath may be accomplished using a magnetic field source and a magnetically permeable leader that releasably attaches to an end of the filament. Upon using an external magnetic field to urge the magnetically permeable leader through one of the channels 155a-155d, from a proximal end to a distal end (or vice versa) of the catheter shaft 120, the leader may be disconnected from the filament, leaving the filament in place along the entire length of one of the channels 155a-155d. In some implementations, the leader may be, for example a re-usable clam shell-style. In some embodiments, the leader may be releasably engaged to the filament by a frictional coupling. In some embodiments, the leader may be urged against a knot formed in the lead end of the filament. In an automated assembly step, a conveyor system may provide relative motion, along the length of the catheter shaft 120, between the MCCI and a magnetic field source (e.g., permanent magnet, electro magnet) that is configured to urge a magnetically permeable leader. When a leader is positioned at one end of one of the channels 155a-155d, the conveyor may impart relative motion between the magnet source and the outer sheath 130 while attracting the leader to remain in close proximity to the magnet source, thereby urging the leader through the longitudinal length of one of the channels 155a-155d. This may automate the process of threading a selected filament into one of the channels 155a-155d after insertion of the insert 135 into the outer sheath 130.
In some embodiments, the functional filaments may be threaded through the channels 155a-155d during insertion of insert 135 into the outer sheath 130 to form the catheter 110.
For example, the filament may be installed in the catheter 110 by attaching the filament to the insert 135 prior to the insert 135 being inserted into the outer sheath 130. In some implementations, the filament may be fixed to a point on the outer sheath 130 near one end, for example, using a weld point. Such a weld point may be made to a metal or plastic ring, for example. The insert 135 may be inserted into the outer sheath 130 at the end proximate the weld point.
In some implementations, during insertion of the insert 135, a filament may, for example, wrap across a lead insertion end of the insert 135. As the insertion is performed, additional length of filament is drawn into two of the channels, as required during the insertion, from a filament supply source and/or from a predetermined length of the filament. In an example, the resulting loop of inserted filament residing in two of the channels 135a-135d may provide a set of steering pull wires for steering the distal tip by applying tension on one or both of the wires using, for example, the catheter handle 115.
In some embodiments, the insert 135 may be pre-installed in the outer sheath 130 prior to insertion of the insert 135.
The various elements used to construct the catheter 110 may allow for advantageously constructing a catheter for various purposes at a reduced labor, time, and expense by construction using a sliding insert, such as the insert 135. Various embodiments may further provide for flexible, on-demand customization of functionality by installing functional filaments according to a customized application to upgrade a supply of one or more catheters pre-assembled with an MCCI.
In an example, the filament to be installed into a selected one of the channels may be a fiber optic thread, which may be used to deliver light to illuminate a distal surface proximate the end of the catheter. In some embodiments, the filament employed in a selected channel may be an imaging technology, which may be used to map a catheter pathway or capture a still or moving image from a distal end of a catheter.
In some implementations, a filament may conduct one or more electrical signals. The various electrical signals may be conveyed via the multiple channel construction of a catheter. One or more channels of various widths may be employed to convey various electrical filaments. These implementations may be combined with other embodiments due to the multiple channel construction of the insert.
In some embodiments, at least one isolated available channel after the MCCI has been inserted into an outer sheath may be employed to convey flowable media. A flowable media may include, for example, gas, liquid, or an alternative fluid. These flowable media may either be delivered into a patient or may be withdrawn (e.g. aspirated) from a patient. An isolated channel may employ a filtering medium (e.g., charcoal or insulation batting) through which to convey a flowable media. In some embodiments, an isolated channel employed to convey flowable media may also employ at least one filament to convey information. The filament employed within the same channel as the flowable media may, for example, convey information relating to the flowable media or the procedure.
In some implementations, at least one isolated channel or an inner lumen may be employed to deliver or withdraw solid media or structure. The delivery of solid media may be, for example, a valve or a stent.
In various embodiments, the number of radially extending members may be between 2 and 20, such as for example at least 4 and not more than 6, at least 8 and not more than 14, or at least 14 and not more than 20.
In some embodiments, a catheter may be constructed by installing a high torque transmission structure coaxially with an MCCI. An example of a high torque transmission structure that may be employed in conjunction with an MCCI is described, for example, with reference to at least FIGS. 2 and 6 of U.S. Provisional Application Ser. No. 62/309,733, titled “Catheter Shaft for High Transfer of Torque,” filed by Farrell, et al., on Mar. 17, 2016, which is incorporated by reference in its entirety herein.
A number of implementations have been described. Nevertheless, it will be understood that various modification may be made. For example, advantageous results may be achieved if the steps of the disclosed techniques were performed in a different sequence, or if components of the disclosed systems were combined in a different manner, or if the components were supplemented with other components. Accordingly, other implementations are within the scope of the following claims.
This application claims the benefit of U.S. Provisional Application Ser. No. 62/309,733, titled “Catheter Shaft for High Transfer of Torque,” filed by Farrell, et al., on Mar. 17, 2016. This application incorporates the entire contents of the foregoing application(s) herein by reference.
Number | Date | Country | |
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62309733 | Mar 2016 | US |