Patent Application
20090076445
The invention relates generally to the field of endoluminal catheters.
Catheter pullback mechanisms are used to provide controlled longitudinal displacement of catheters, such as intravascular catheters, during diagnostic and/or treatment procedures. Various catheter pullback mechanisms have been described in the art.
U.S. Pat. No. 6,814,727 discloses automatic/manual longitudinal position translator and rotary drive system for catheters, and is incorporated herein by reference in its entirety.
U.S. Pat. No. 6,506,144 discloses a pullback mechanism for an in-situ treatment device such as a catheter, and is incorporated by reference herein in its entirety.
In view of the above, what is needed are improved catheter pullback devices that better maintain sterility within the vicinity of use while permitting re-use of core components.
The invention overcomes the drawbacks and disadvantages of the prior art by providing catheter pullback (PB) mechanism assemblies in which a reusable drive component is enclosed by a sterile barrier enclosure, such as a polymeric sheath/bag.
One embodiment of the invention provides a catheter pullback apparatus, including:
a reusable elongate drive unit comprising a pullback carriage;
a sterile barrier enclosure sized and configured to surround the reusable elongate drive unit;
a base unit sized and configured to receive the reusable elongate drive unit surrounded by the disposable sterile barrier enclosure; and
a catheter shuttle slideably engaged with the base unit and magnetically coupleable to the pullback carriage of the reusable elongate drive unit.
Another embodiment of the invention provides a catheter pullback apparatus, including:
a reusable elongate drive unit comprising a pullback carriage;
a sterile barrier enclosure sized and configured to surround the reusable elongate drive unit;
a base unit sized and configured to receive the reusable elongate drive unit surrounded by the disposable sterile barrier enclosure; and
a catheter shuttle comprising a barrier piercing member and slideably engaged with the base unit, said shuttle mechanically coupleable to the pullback carriage of the reusable elongate drive unit by the barrier piercing member.
The sterile barrier enclosures may be single-use, disposable items, for example, polymeric disposable polymeric sleeves or bags. Preferably, the base unit is sterilizable and reusable, so that both the base unit and drive unit may be re-used.
Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed.
The invention overcomes the drawbacks and disadvantages of the prior art by providing catheter pullback device assemblies in which a reusable drive component is enclosed by a sterile barrier enclosure, such as a polymeric sleeve/bag.
Magnetic Coupling-Based Pullback Apparatuses
One embodiment of the invention provides a catheter pullback apparatus, including:
a reusable elongate drive unit comprising a pullback carriage;
a sterile barrier enclosure sized and configured to surround the reusable elongate drive unit;
a base unit sized and configured to receive the reusable elongate drive unit surrounded by the disposable sterile barrier enclosure; and
a catheter shuttle slideably engaged with the base unit and magnetically coupleable to the pullback carriage of the reusable elongate drive unit.
In an assembled state, the apparatus includes:
a reusable elongate drive unit comprising a pullback carriage;
a sterile barrier enclosure conformably surrounding the reusable elongate drive unit;
a base unit sized and configured to receive the reusable elongate drive unit surrounded by the disposable sterile barrier enclosure, in which base unit the same is secured; and
a catheter shuttle slideably engaged with the base unit and magnetically coupled to the pullback carriage of the reusable elongate drive unit.
The sterile barrier enclosure may be for single-use and disposable or may be re-usable following sterilization. The sterile barrier enclosure may, for example, be a polymeric sleeve, preferably closed at one end, or elongated “bag.” The sterile barrier enclosure may be flexible and membranous in form. The sterile barrier enclosure may, for example, be made from a polypropylene or polyethylene.
As used throughout this disclosure, the terms pullback carriage and pullback shuttle are equivalent and refer to the longitudinally displaceable member of the pullback drive unit that couples with the catheter shuttle to provide longitudinal displacement of a catheter.
Various aspects of magnetic coupling-based embodiments of the invention are described below with reference to appended
Catheter shuttle rollers may not be necessary depending upon toughness and friction properties of sterile bag/sleeve material utilized and, thus, are optional. Furthermore, if a suitably strong magnetic field is utilized, the catheter shuttle may not need to be in contact with the sterile sleeve at all. A small separation distance between magnetic elements is desirable for better coupling.
Magnetic coupling is shown in the embodiments of the figures with dual magnets on pullback and catheter shuttle aligned for +/− attractive coupling. Neodymium (Nd—Fe—B alloy) rare-earth magnets are well suited to the present invention, but other permanent magnets may also be used, for example, samarium cobalt, ceramic, AlNiCo, and conductive polymer magnets. In practice, any suitable type, number and/or configuration of magnets may be used.
Alternative embodiments may use magnets on one side only with iron-based magnetic alloys such as ferritic and martensitic 400 series stainless steels. Alternatively, magnetically conductive particles can be mixed in with plastic or insert molded to provide suitable coupling features. Alternatively, electromagnets in the motor housing may be used, which can be switched on during use and off when not in use to limit magnetic interaction with other equipment and devices in the vicinity.
Mechanical Coupling-Based Embodiments
One embodiment of the invention provides a catheter pullback apparatus, including:
a reusable elongate drive unit comprising a pullback carriage;
a sterile barrier enclosure sized and configured to surround the reusable elongate drive unit;
a base unit sized and configured to receive the reusable elongate drive unit surrounded by the disposable sterile barrier enclosure; and
a catheter shuttle comprising a barrier piercing member and slideably engaged with the base unit, said shuttle mechanically coupleable to the pullback carriage of the reusable elongate drive unit by the barrier piercing member.
Thus, the catheter shuttle and pullback carriage are mutually adapted to mechanically couple via the piercing member. In practice, the drive unit surrounded by the sterile barrier is placed in the base unit and concomitantly or thereafter the barrier is pierced by the piercing member of the catheter shuttle to mechanically engage the piercing member with the pullback carriage.
In an assembled state, the apparatus includes:
a reusable elongate drive unit comprising a pullback carriage;
a sterile barrier enclosure conformably surrounding the reusable elongate drive unit;
a base unit sized and configured to receive the reusable elongate drive unit surrounded by the disposable sterile barrier enclosure, in which base unit the same is secured; and
a catheter shuttle comprising a barrier piercing member and slideably engaged with the base unit, said shuttle mechanically coupled to the pullback carriage of the reusable elongate drive unit by the barrier piercing member.
Various aspects of mechanical coupling-based embodiments of the invention are described below with reference to appended
The base unit of the apparatuses of the invention may re-usable and sterilizable, for example, by autoclaving. The base unit may for example be metallic and/or polymeric in composition. For example, the housing and body of the catheter shuttle of the base unit may be at least partially made from stainless steel or titanium. The sterile barrier enclosure is preferably a single-use disposable product. The reusable drive unit may be at least partially sterilized between uses using gentle methods such as light surface washing with ethanol, but potential contamination arising from the drive unit is primarily limited by the sterile barrier enclosure.
Any suitable type of linear actuator may be used according to the invention. A simple stepper motor-based linear actuator (such as those provided by Haydon Switch & Instrument, Inc., Waterbury, Conn.) utilizing a lead screw is shown as one example. Alternative drive systems include belt drive, rack & pinion drive, friction wheel/rolling drive, piezo-electric linear actuators, and linear motors and other commonly known linear transducers known in the field of machine design. Both stepper and servo-type motors are suitable as well and may require sensors for shuttle position sensing at start and end of travel locations, or a full linear encoder to provide feedback to drive system.
The pullback drive system may be coupled to a separate power supply or provided from on-board batteries (not shown in figures). External Input/Output communications can also be provided through cabling or wireless means (radio frequency, ultrasonic or infrared based signal transmission).
The invention also provides methods for controlling the position of an endoluminal catheter, that include the steps of:
providing any of the catheter pullback apparatuses described herein;
securing a longitudinally displaceable shaft/element of a catheter to the catheter shuttle; and
selectively longitudinally displacing the pullback carriage to longitudinally displace the catheter shaft/element.
Although the foregoing description is directed to the preferred embodiments of the invention, it is noted that other variations and modifications will be apparent to those skilled in the art, and may be made without departing from the spirit or scope of the invention. Moreover, features described in connection with one embodiment of the invention may be used in conjunction with other embodiments, even if not explicitly stated above.
This application claims the benefit of U.S. provisional patent application Ser. No. 60/929,919 filed Jul. 18, 2007, which is incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60929919 | Jul 2007 | US |
