Patent Description:
There is a wide range of applications where there is a need for using a system inside a pipe, a duct or a tube, for example for the placement of the distal part of a tube in a specific location, for bringing light or chemicals, or for bringing a functionality at a remote or hard-to-access place.

When advancing a system in the lumen of a pipe, duct or a tube, it is important that the user can control carefully and precisely the movement and the placement of the system. Placement of systems within pipes is a known technical issue in oil engineering or in motor engineering. Placement of systems within body tubes, such as for example through the ostium (of a vein, an artery, the gastro-intestinal track. etc), is also known in the medical field as being a difficult challenge.

For example, the document <CIT> discloses a cardiac catheter which may avoid the need for catheter exchange to access two ostia. Instead of a C-shaped distal part, the catheter described in <CIT> includes a distal portion attached to the intermediate section and consists of a double or a reverse curve (S-shaped). The structure allows the catheter to be utilized to enter either left or right ostium without catheter exchange by rotation of the catheter about its axis. However, this system comprises a plurality of curves. Therefore, during the progression of said guiding means in the aortic artery, the device contacts and pressures the walls of the artery, and can be harmful for the patient. Nonharmful investigation may be performed by curving appropriately particular zones of a catheter or endoscope by using various kinds of actuators along its structure. However, the higher the number of actuators on the flexible structure is and the more difficult the activation and the control of said system are.

Consequently, there always is a need for providing optimized systems. Especially, there is a need for elongated systems (such as for example catheters) designed to be advanced in a tube, and having an improved control of their movement within said tube (for example a body tube).

A good steerable functional system intended for nonharmful and controlled investigation should be adaptable to the tortuosity of the tube, for example of the vascular system, and more particularly it should allow to get:.

The document <CIT> discloses a steerable structure wherein the parts of the flexible body including actuators are thickened in order to form short radius curves. However, the thickened parts do not allow compact double curves or independent curves so that complicates the navigation of the steerable structure within the tube, duct or pipe. And, the disclosed structure does not allow forming compact S-shaped curves with a short radius. <CIT> describes an elongated functional system configured to be advanced in the lumen of a pipe, a duct or a tube, said system comprises: an elongated flexible body, multiples strengthening member, whereby the elongated body includes an overlapping region along which at least the proximal extremity of one first strengthening member overlaps with at least the distal extremity of one second strengthening member.

Thus, an object of the present invention is to provide steerable systems able to form compact S-shaped curves with short radius that can form independently, for the investigation of a pipe, a duct or a tube, preferably in the human body.

Thus, the present invention relates to an elongated functional system configured to be advanced in the lumen of a pipe, a duct or a tube, said system comprising:.

wherein the elongated body includes an overlapping region along which at least the proximal extremity of the first actuator overlaps with at least the distal extremity of the second actuator, characterized in that the first actuator and the second actuator are mechanically independent from one another and longitudinally offset from one another.

According to one embodiment, the elongated flexible body comprises or consists of at least one tube, blade or wire.

Alternatively, the elongated flexible body has a cross-section profile under a form selected from star, circular, semicircular, square, rectangular, triangle, pyramidal or any combinations thereof.

According to another embodiment, the blade presents an upper face on which is arranged the first actuator and a lower face on which is arranged the second actuator.

According to one embodiment, the elongated body includes an overlapping region along which at least the proximal extremity of the first actuator overlaps with at least the distal extremity of the second actuator.

In a particular embodiment, the overlapping region consists of overlapping the proximal extremity of the first actuator with the distal extremity of the second actuator.

According to one embodiment, the first actuator and the second actuator are located on the surface of the elongated flexible body, and are diametrically opposed.

It is possible to have a configuration where the first actuator and the second actuator are fixed at least partially to the elongated flexible body with fixing means in the overlapping region.

Alternatively, the elongated functional system further includes at least a third actuator, wherein the actuators are substantially equidistant one from another in the circumferential direction of the tube.

In a specific embodiment, the elongated functional system further comprises at least a third actuator and at least a second overlapping region distinct from the first overlapping region and along which the proximal or the distal extremity of the third actuator faces the proximal or the distal extremity of at least one of the first actuator or of the second actuator.

According to one embodiment, the actuators are configured for being actuated independently one from the other.

According to one embodiment, the elongated functional system is a catheter, a catheter guide or an endoscope.

The present invention also relates to a method for controlling advancement of the elongated functional system of the invention, in the lumen of a pipe, a duct or a tube, said method comprising:.

Alternatively, in the method of the invention:.

and wherein controlling the first and second actuators comprises:.

According to one embodiment, in the method of the invention, activating actuators comprises using physical and/or chemical means.

This invention relates to an elongated functional system <NUM> which may be a catheter, a catheter guide or endoscope, intended to be used for investigating a pipe, a duct or a tube.

One goal of this invention is to provide a steerable system able to form compact S-shaped curves made by two sections associated to actuators, said sections can be activated independently with a short radius, for the investigation of a pipe, a duct or a tube, preferably in the human body.

As illustrated in <FIG>, the system includes an elongated body <NUM>, which is flexible, and presents a proximal part <NUM> and a distal part <NUM>. The distal part <NUM> is contiguous to proximal part <NUM> and extends it. The elongated body <NUM> has an axis of symmetry A1. If the elongated body <NUM> was a blade, A1 would be a symmetry plan rather than a symmetry axis.

The elongated flexible body <NUM> may for example be in the form of a cylindrical shape, for example of a circular section (i.e. a tube). In other non-shown embodiments, the flexible body <NUM> may be cylindrical with another possible section, such as a cross-section profile under a form selected from star, circular, semicircular, square, rectangular, triangle, pyramidal or any combinations thereof. According to an embodiment, the elongated flexible body may contain three tubes or more. For example, the elongated body may be formed by three tubes arranged in a pyramidal shape, that is, two parallel and contiguous tubes and a third tube on top of them.

The elongated flexible body <NUM> may for example have a length ranging from <NUM> to <NUM>; preferably from <NUM> to <NUM>; more preferably is about <NUM>. According to one embodiment, the elongated functional system <NUM> has a length from <NUM> to <NUM>; preferably from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, or from <NUM> to <NUM>. According to one embodiment, the elongated functional system <NUM> has a length from <NUM> to <NUM>; preferably from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, from <NUM> to <NUM>, or from <NUM> to <NUM>. According to an embodiment, the length of the flexible body is in the range <NUM> to <NUM>, preferably <NUM> to <NUM>.

According to an embodiment, the width or diameter of the flexible body is in the range <NUM> to <NUM>. According to one embodiment, the elongated flexible body <NUM> has a diameter ranging from more than <NUM> to <NUM>; preferably from <NUM> to <NUM>. According to one embodiment, the elongated functional system <NUM> has a diameter of about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>. According to one embodiment, the elongated functional system <NUM> has a diameter of about <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM>; <NUM> or <NUM>. According to one embodiment, the elongated flexible body <NUM> has a diameter ranging from more than <NUM> to <NUM>; preferably from <NUM> to <NUM>; more preferably of about <NUM> or <NUM>.

According to an embodiment, the body <NUM> is made for example of elastic or another flexible material, or an elastic material assembly. In one embodiment, the body part <NUM> is made of polymer flexible material suitable for invasive use. In one embodiment, the body <NUM> is made of a super-elastic alloy. Any super-elastic alloy may be used in this invention. In one embodiment, the super-elastic alloy is nitinol.

A first actuator <NUM> is arranged on the elongated flexible body <NUM>, and includes a proximal extremity <NUM> and a distal extremity <NUM>. A second actuator <NUM> is arranged on the same elongated body <NUM> and includes a proximal extremity <NUM> and a distal extremity <NUM>. Specifically, the first actuator <NUM> is arranged in the distal part <NUM> of the elongated body <NUM> and the second actuator <NUM> is arranged in the proximal part <NUM>. With such configuration, the first actuator <NUM> and the second actuator <NUM> are mechanically independent from one another and axially offset along the axis A1 of symmetry of the elongated functional body <NUM>. It is possible to activate only one actuator <NUM> or <NUM> and obtain a J shaped curve. This allows forming independent short radius curves when necessary during progression of the functional system in the tub. Being mechanically independent, each actuator can be actuated separately and guide the associated elongated functional system <NUM> in a specific direction. In addition, being axially offset along A1, the curvatures obtained can lead to a S-shaped configuration. The axial/longitudinal offset along A1 is important in this matter, otherwise an S-shaped form could not be reached.

The first and second actuators <NUM>, <NUM> are arranged:.

According to an embodiment, the functional system <NUM> includes at least a third actuator. According to an embodiment, the first, second and third actuators are equidistant one from another in the circumferential direction of the tube. According to an embodiment, the elongated functional system further comprises at least a third actuator and at least a second overlapping region distinct from the first overlapping region and along which a proximal or a distal extremity of the third actuator faces the proximal or the distal extremity of at least one of the first or second actuator.

According to an embodiment, the system further comprises at least a third and a fourth actuators and at least a second overlapping region distinct from the first overlapping region along which a proximal extremity of the third actuator faces a distal extremity of the fourth actuator.

As illustrated on <FIG>, the overlapping region is characterized by its length W ranging from more than <NUM> to the size of one of the actuators. According to one embodiment, the length of the overlapping region W is about the size of one fixing mean of the actuator on the body <NUM>. According to one embodiment, the length of the overlapping region W is about the size of two fixing means of the actuator on the body <NUM>. According to one embodiment, the length of the overlapping region W is higher than the size of two fixing means of the actuator(s) on the body <NUM>.

According to one embodiment, the length of the overlapping region W ranges from more than <NUM>% to <NUM>% of the length of at least one of overlapped actuators. According to one embodiment, W ranges from <NUM>% to <NUM>%, preferably from <NUM>% to <NUM>%, from <NUM>% to <NUM>%, of the length of at least one of overlapped actuators.

According to an embodiment, the length of the overlapping region W is in the range <NUM> to <NUM>. For example, when length of the actuators is <NUM>, W ranges from <NUM> to <NUM>.

The embodiments of <FIG> and <FIG> are globally similar but the three elongated functional systems include overlapping regions of variable lengths W1, W2 and W3.

According to one embodiment, the actuator <NUM>, <NUM> may be in the shape of a wire, an ensemble of wires or a blade of memory type. According to one embodiment, the blade shaped elongated body is advantageous in that it bends along a predictable direction. Moreover, it presents two opposite planar surfaces suitable for an easy integration of elements such as actuators. According to an embodiment, the blade presents an upper face on which is arranged the first actuator and a lower face on which is arranged the second actuator.

According to one embodiment, the actuators <NUM>, <NUM> may be actuated by any techniques known by the skilled artisan, including physical and/or chemical means. According to one embodiment, the actuator <NUM>, <NUM> may be actuated by any actuating techniques such as those comprising using balloons that are inflated with air or fluid. According to one embodiment, the actuator <NUM>, <NUM> may be actuated by using a material able to react to a physical stimulus such as electrical signal or heat, for example. According to an embodiment, the actuator <NUM>, <NUM> is made of, or comprises:.

According to an embodiment, at least one of the actuators is made of nitinol, for example composed of <NUM>% of Ni and <NUM>% of Ti.

In one non-shown embodiment, the elongated functional system <NUM> further comprises an energy source, such as for example an electric energy source, and means for providing and/or for transmitting energy from the energy source to the first actuator <NUM> and/or to the second actuator <NUM>. Said energy is transformed by the actuating element-actuator <NUM> or <NUM> - into a mechanical energy so as to obtain a curvature, thus facilitating the navigation inside the tube, pipe or duct. Since the actuators <NUM> and <NUM> are independent, they can be actuated independently by the energy source.

According to one embodiment, each actuator is connected to at least two conductive wires. According to one embodiment, two actuators are connected to at least three conductive wires. According to one embodiment, the conductive wire is made of copper. For example, a first set of conductive wires may be connected to the first actuator <NUM> and a second set of conductive wires connected to the second actuator <NUM>. Alternatively, both of the first and second actuators may be connected by the same wire or set of wires.

The conductive wire(s) is/are arranged to provide or to transmit an electric current along their longitudinal portion to the first actuator and/or the second actuator in a controlled manner. According to another embodiment, the elongated functional system <NUM> further comprises an external control unit located at a proximal end of the elongate functional system. The control unit comprises at least one controller device configured to actuate independently or simultaneously the actuators.

According to one embodiment, the first set of conductive wires is connected to a first controller. According to one embodiment, the second set of conductive wires is connected to a second controller. The first controller and/or the second controller allow applying an electric current to respectively the first actuator and/or the second actuator by means of the conductive wires, thereby providing the actuation of at least one of said actuators.

According to one embodiment, the overlapped actuators are configured for being actuated independently one from the other. This allows forming independent short radius curves when necessary during progression of the functional system in the tube.

According to one embodiment, even if actuators are not actuated, the overlapping region between the overlapped actuators allows achieving a rigidity that creates the principle of reserve. According to one embodiment, when at least one actuator is actuated, the overlapping region becomes more rigid. According to the invention, when at least one actuator is actuated, the stiffening of the overlapping region induces curving of the actuated actuator on the non-overlapped portion, and said resulting curve radius is shorter than the curve radius obtained without the presence of the overlapping region.

According to one embodiment, when two opposite actuators that overlap are actuated, the stiffening of the overlapping region amplifies the curvature of the two actuated actuators and the body <NUM> takes a S-shape form; said S-shape curve is shorter and more compact than those obtained without the presence of the overlapping region. According to another embodiment, at least two actuators may be actuated together for forming an S-shaped double curve. This allows a more efficient control of the functional system in particular when navigating through a tube having two successive compact and opposite curvatures.

According to one embodiment, the curves triggered by each actuator may be generated independently in a controlled way.

According to one embodiment, the S-shape curve is characterized by two curve radius r<NUM> and r<NUM>. According to one embodiment, r<NUM> and r<NUM> are, each taken independently, higher or equal to <NUM>. According to one embodiment, the S-shape curve is characterized by the length of the curve L (i.e. the length of the shortest straight line from the beginning to the end of the S-shape curve). According to one embodiment, the lengths of the curves L obtained according to the invention are shorter than those obtained without the presence of the overlapping region.

Each actuator <NUM>, <NUM> is fixed to the elongated body <NUM> by using fixing means <NUM>. Advantageously, in one non-shown embodiment the first and second actuators <NUM>, <NUM> may be fixed by using the same fixing means in the overlapping region. This allows reducing the number of fastening means.

In <FIG>, the actuators <NUM>, <NUM> are not activated. The activation of the first actuator <NUM> and/or of the second actuator <NUM> drives the deformation respectively of said actuators.

As the actuators are fixed to the elongated body <NUM>, the deformation of the actuators (i.e. a shortening of the length of the actuator and/or a curvature of the actuator) results in the curvature of the elongated body <NUM>. Especially, the actuation of the overlapped actuators fixed to the elongated body <NUM> allows a better compactness of their curvatures. More precisely, the curved parts are those parts to which the actuators are fixed, but not the overlapping region.

<FIG> shows an elongated functional system <NUM> similar to that of <FIG> with a slight difference in the length of the overlapping region W. In this embodiment as shown, both actuators <NUM>, <NUM> have been activated so that a compact double curvature (S-shape) is obtained.

<FIG> shows another embodiment of an elongated functional system <NUM> including an elongated body <NUM> having a blade shape, such blade has also a symmetry plane not represented. The body <NUM> includes (inside or on the body) a first and a second actuators<NUM> and <NUM> axially offset along the elongated body <NUM> and defining an overlapping region W. The first actuator <NUM> is fixed to the upper face <NUM> of the body <NUM> while the second actuator <NUM> is fixed to the bottom face <NUM> of the elongated body <NUM>. According to an embodiment, the actuators <NUM>, <NUM> are also of a blade shape. However, other shapes are also possible. For example, the first and /or the second actuators may include one or more elongated wires.

<FIG>, shows another embodiment wherein the elongated flexible body <NUM> presents a distal part <NUM> having a tip <NUM> and comprising the first actuator <NUM>. This advantageous embodiment allows to master guidance of the distal part of the functional system during its progress in the tube (or pipe or duct). The elongated flexible body <NUM> has a longitudinal axis A1. The presence of the tip <NUM> allows protection of the tube from any perforation or hit that could be caused by the flexible body, and that could affect the integrity of the walls of the tube, or harm a patient in case the tube is the aortic artery for example.

The present invention also relates to a method for controlling advancement of the elongated functional system of the invention, in the lumen of a pipe, a duct or a tube.

According to one embodiment, said method comprises:.

According to one embodiment, the method is particularly suitable for surgical and/or medical investigation. According to one embodiment, the tube is a vein or an artery, preferably is the aortic arch.

According to one embodiment, the first actuator and the second actuator are arranged in the distal part of the elongated flexible body <NUM>.

According to one embodiment, controlling the first and second actuators comprises:.

According to one embodiment, controlling of the actuators <NUM>, <NUM> comprises:.

The first actuator being the distal actuator and the second actuator being the proximal actuator.

According to one embodiment, the method of the invention further comprises a step for deactivating the elongated functional body <NUM>.

Claim 1:
An elongated functional system (<NUM>; <NUM>) configured to be advanced in the lumen of a pipe, a duct or a tube, said system comprises:
- an elongated flexible body (<NUM>; <NUM>),
- at least one first actuator (<NUM>; <NUM>) arranged in or on the elongated flexible body (<NUM>; <NUM>),
- at least one second actuator (<NUM>; <NUM>) arranged in or on the elongated flexible body (<NUM>; <NUM>),
- each actuator (<NUM>; <NUM>, <NUM>; <NUM>) presenting proximal and distal extremities, being connectable to a source of energy and configured to convey or transform an amount of energy to the elongated flexible body (<NUM>; <NUM>) sufficient to cause a reversible curvature of a part of the elongated flexible body (<NUM>; <NUM>),
wherein the elongated body (<NUM>; <NUM>) includes an overlapping region (W) along which at least the proximal extremity (<NUM>) of the first actuator (<NUM>; <NUM>) overlaps with at least the distal extremity (<NUM>) of the second actuator (<NUM>; <NUM>), and wherein, further, the first actuator (<NUM>;<NUM>) and the second actuator (<NUM>; <NUM>) are mechanically independent from one another and longitudinally offset from one another.