WO2013063711A1

WO2013063711A1 - Expandable catheter

Info

Publication number: WO2013063711A1
Application number: PCT/CH2012/000248
Authority: WO
Inventors: Albino Triaca; Michael Schwager
Original assignee: Schwager Medica Ag
Priority date: 2011-11-04
Filing date: 2012-11-05
Publication date: 2013-05-10
Also published as: CH705727A1

Abstract

The invention relates to a balloon catheter having a guide wire, suitable for expanding tissue, and a pressure-tight closure, wherein the balloon is provided in the form of a flat disc. The balloon is preferably of double-walled construction and withstands pressures of up to 40 bar.

Description

Spreizkatheter

Technical area

The invention relates to a balloon catheter with a guide wire, which is suitable for spreading tissue.

State of the art

Balloon catheters are commonly used to fix a particular type of catheter in the relevant hollow organ of a human or an animal. The catheter is for diagnostic (research-related) or therapeutic (treatment-related) purposes. Typically, the hollow organs are urethra, esophagus, bile ducts, vessels, arteries, especially arteries of the heart.

It is important to make the balloon catheter as small as possible in terms of wall thickness. At the same time, the sliding and flexibility properties should be as good as possible and the risk of tearing during the insertion process should be very small. The balloon is usually rolled up or collapsed. The catheter then has a small spherically symmetric thickening at the appropriate location, which is the most favorable for the insertion of such a catheter into a hollow organ, since it offers the least resistance and risk so little injury.

DESCRIPTION OF THE INVENTION The object of the invention is to provide a catheter which belongs to the technical field mentioned at the outset and which can be used for spreading tissue lying close to one another. By using the catheter according to the invention, a previously non-existent cavity is created or an existing cavity is widened. The solution of the problem is defined by the features of claim 1. According to the invention, there is a balloon catheter for spreading tissue having a guidewire, the balloon catheter having a pressure-tight seal.

The invention relates to a balloon catheter which has at least one expansion space at its distal portion and is suitable for spreading tissue. The tissue may be any human or animal tissue, e.g. Skin tissue, muscle tissue, connective and supportive tissues such as cartilage, fat and especially bone. It is also within the scope of the invention to enlarge a gap between two different fabrics. A balloon catheter according to the invention is also particularly suitable for use in the nose area, for. B. for widening the nasal passage.

The gap in this tissue, which is to be widened, is naturally given, or it is caused by external influences. In particular, it can be selectively generated by a cut. The balloon catheter is inserted with its distal end first into the gap in the tissue to be spread. The proximal end of the catheter remains accessible from the outside.

The expansion space of the balloon is initially empty. It is in the form of a flat disc, so that the catheter can be inserted as easily as possible into the tissue gap. In contrast, balloons are usually rolled up to be able to be introduced as possible with little resistance in a hollow organ.

Accurate placement of the balloon catheter in the tissue slot is accomplished by the flexible guidewire that extends along a balloon catheter longitudinal axis. If the catheter is in the correct position, the expansion chamber is filled with a liquid or gaseous medium. The balloon expands, thereby expanding the gap in the tissue. The amount of medium can be controlled precisely and thus a defined pressure can be set.

Once the desired pressure has been reached, the catheter is closed pressure-tight at its proximal end. Thus, the set pressure over a longer period, eg. B. be maintained for several days or weeks. It is also within the scope of the invention not to leave the balloon catheter at the set position for a long period of time. It can also be used once. In particular, however, the balloon catheter can also be used within the scope of an application series in a defined time scheme, eg daily or weekly over a longer period of time being able to be removed again and again between the individual applications.

The filling of the balloon is reversible. So it is possible to vary the pressure during an application. In particular, the pressure can be increased gradually. This is particularly advantageous if the tissue has to be spread relatively far, and this process generates a high load (pressure, tension) on the surrounding areas. As the pressure within the balloon gradually increases, the surrounding areas have sufficient time to adapt to the changing conditions (eg stretching of the skin). After use, the pressure-tight catheter is opened and the expansion chamber emptied. The balloon collapses, leaving a widened gap in the tissue. The catheter can now be removed from the tissue. This happens either at the end of a longer-term application or regularly after individual applications in the context of an application series. Preferably, the balloon is provided in the form of a flat disc. This allows the balloon to be inserted particularly easily into a relatively narrow gap.

But it is also possible to provide folded or rolled up balloons.

Preferably, the balloon catheter has at least two balloon envelopes arranged one inside the other. The pressure which can be applied to a multi-walled catheter in which two or more slidable balloon shells lie directly on top of one another is significantly increased in relation to the wall thickness in comparison to single-walled catheters. In this case, the total thickness of the balloon envelopes may even be substantially smaller than that of a balloon catheter with a single balloon envelope (single balloon). The individual balloon envelopes support each other when pressure is applied. In addition, multi-walled balloon envelopes can better conform to the surrounding tissue to be spread, both during insertion and when filling / emptying the balloon catheter with the liquid or gaseous medium. Thus, the applied pressure can be evenly distributed on the surface. Point to single balloons Double-walled balloons increased flexibility and compressive strength with less total wall thickness.

However, it can also be used single-walled balloons.

In a preferred embodiment, the balloon catheter is designed such that it can withstand a pressure of at least 20 bar. It is particularly preferably designed for a pressure of up to 40 bar. This pressure is achieved when filling the liquid or gaseous medium. Preferably, the pressure is adjusted via a suitable device to which a pressure gauge is connected.

As a result, the tissue is spread to the desired extent. Such high pressures are especially necessary when very strong tissue is to be spread, z. B. bone tissue. For softer tissue, z. As skin already lower pressures.

This compressive strength of the balloon catheter is necessary for several reasons. On the one hand, an undesirable expansion after a certain time under pressure load must be prevented. An additional expansion could lead to an overload of the surrounding tissue and z. B. to cause tearing of the tissue to be stretched. At the same time bursting of the balloon catheter must be avoided, as this would be associated with an uncontrolled, explosive escape of the filled medium. In order to be able to spread the tissue anyway, the damaged balloon catheter would have to be replaced, requiring additional surgery on the patient, and making the entire process of spreading more complicated and longer.

The balloon length along the guidewire is adjusted to the tissue slit that is to be spread. Preferably, the length of such a balloon is about 10-15 mm.

The initially flat balloon is expanded by filling with a gaseous or liquid medium. In a preferred embodiment, the total diameter of the expanded balloon is max. 10 mm.

Preferably, balloon materials are used which have a certain lubricity, so that they can be pushed well into the tissue gap. simultaneously the materials should be flexible and low stretchy. Therefore, the balloon catheters according to the invention preferably consist of a polyamide, nylon and / or polyester.

After filling with a gaseous or liquid medium, the catheter is sealed pressure-tight.

Preferably, the shutter mechanism is a valve. In this case, a valve is an element for blocking but especially for controlling the flow of fluids.

It is also conceivable to seal the catheter pressure-tight with completely different devices, for. B. with a cap directly on the proximal catheter end or a device for crushing. These are cheaper closure variants. However, it can not be ensured that no filling medium escapes when closing. Thus, with these closure variants, there is a certain inaccuracy in the applied pressure. Preferably, the pressure-tight seal is in the proximal portion of the catheter, but not at its end. It is particularly preferably arranged at a distance of about 0.5-1.0 cm to the proximal end of the catheter. This makes it possible to guide a conical attachment in the proximal end of the catheter and so easily fill the catheter with a gaseous or liquid medium. Alternatively, it is possible to provide the pressure-tight seal directly at the proximal end of the catheter. However, it must then be ensured in another way that the medium used for filling does not escape. Are conceivable as z. B. special adapters or seals.

For a good handling of the pressure-tight closure is preferably arranged at a distance of about 5 cm from the balloon.

Particularly preferably, the pressure-tight closure is a one-way valve. Via a one-way valve, the balloon can be filled, so that the gaseous or liquid medium in the Balloon arrives. However, the medium can not escape again, the pressure remains constant. However, with a one-way valve, it is possible to gradually increase the pressure. After completion of the application, the entire valve is removed by, for. B. the catheter is severed at a distally located by the one-way valve from the point. The pressure is thus reduced and the medium can escape or be removed from the catheter.

In an alternative embodiment, the valve may be a two-way valve. With a two-way valve, it is possible to increase or decrease the pressure within the balloon catheter, since both medium can be added and withdrawn. After use, it is not necessary to remove the valve from the catheter. Thus, a catheter according to the invention having a two-way valve as a shutter mechanism can be used several times. The disadvantage, however, is that a two-way valve takes up more space than a one-way valve and also is more expensive. Preferably, the one-way valve is located in the proximal portion of the catheter, but not at its end. It is particularly preferably arranged at a distance of about 0.5-1.0 cm to the proximal end of the catheter. This makes it possible to guide a conical attachment in the proximal end of the catheter and so easily fill the catheter with a gaseous or liquid medium. Alternatively, it is possible to provide the pressure-tight seal directly at the proximal end of the catheter. However, it must then be ensured in another way that the medium used for filling does not escape. Are conceivable as z. B. special adapters or seals.

For a good handling, the one-way valve is preferably arranged at a distance of about 5 cm from the balloon.

The guidewire has a very small diameter. It protrudes beyond the balloon catheter at the distal end and, thanks to its low resistance and flexibility, facilitates good positioning in the tissue gap. It consists of good sliding, flexible and tough material, preferably stainless steel, aluminum or of plastics with high mechanical strength, for example PVC, polyamide or polyester.

The guidewire is sealed to the balloon so that pressure can be maintained within the balloon. Commonly used sealing methods include welding, gluing or ultrasonic. With these methods, a significant thickening of the balloon diameter is avoided at the relevant point.

Vorteiihafterweise at least one balloon envelope and / or the guide wire is at least partially colored, reflective and / or fluorescent. Also, inside the balloon catheter at least one radiopaque marker may be attached, for example in the form of a radiopaque marker ring. Thanks to this marking, the exact position of the balloon catheter placed in the tissue can be determined on the basis of X-ray images and, if necessary, corrected. These markers are also important in the longer whereabouts of the catheter, as so the correct position can be checked periodically. A catheter according to the invention is particularly suitable for widening the nasal passage. For this purpose, the balloon catheter is placed in the nasal passage and for a few minutes, e.g. inflated for 2 min. Subsequently, the balloon catheter is removed. This process is repeated daily. Overall, the period of application extends over several weeks or months. Through this application series, the nasal passage can be widened permanently. As a result, breathing can be improved and, in particular, snoring problems can be reduced. The application is carried out by a specialist.

But it is also possible that described daily application by the patient himself. In particular, by a suitable marker, for example a color marking, a balloon catheter according to the invention for widening the nasal passage can also be offered for home use. A patient can use the marker to check the correct positioning of the balloon catheter and thus carry out the daily application independently. It is then not necessary to schedule an appointment with a specialist on a daily basis. It is sufficient to check the course of the application with regular checks. From the following detailed description and the totality of the claims, further advantageous embodiments and feature combinations of the invention result.

Brief description of the drawings

The drawings used to explain the embodiment show:

Fig. 1 a, b a novel balloon catheter with a guide wire and a valve in the unexpanded state in plan view and side view;

2a, b a balloon catheter according to the invention with a guide wire and a valve in the expanded state in plan view and side view;

3a-e show the schematic course of a spreading of muscle tissue with a balloon catheter according to the invention;

Fig. 4a-f shows the schematic course of a two-stage spread of

Bone tissue with a balloon catheter according to the invention;

Fig. 5a, b, a suitable one-way valve for an inventive

Balloon catheter.

Basically, the same parts are provided with the same reference numerals in the figures.

Ways to carry out the invention

Fig. 1a, b shows a novel balloon catheter 1 in unexpanded form in plan view (a) and side view (b). The balloon catheter 1 has a balloon 2, a guide wire 3 and a one-way valve 4. The balloon 2 is located in the distal region 5 of the balloon catheter 1. The guide wire 3 protrudes at the distal end 6 of the balloon catheter 1. The one-way valve 4 is located in the proximal region 7, which is arranged in the vicinity of the proximal end 8 of the balloon catheter 1. The balloon 2 is arranged flat. In the plan view (Figure 1a), it can be seen that the balloon is like a disc and is not rolled up. In the side view (FIG. 1 b), it can be seen that the balloon is not expanded and thus has a diameter d 1 as the entire catheter. Fig. 2a, b shows the inventive balloon catheter 1 in an expanded form. While no difference to non-expanded state can be seen in the plan view (FIG. 2 a), the side view (FIG. 2 b) shows that the balloon has expanded and now has a diameter d 2 that is significantly greater than the diameter of the entire catheter. In Fig. 3a-e it is shown how with the aid of the inventive balloon catheter 1, a tissue gap is spread.

Fig. 3a shows a section of the muscle tissue 10.1, 10.2, which has a gap 1 1 of the width a. The catheter 1 is introduced with the distal end 6 ahead with the help of the guide wire 3 in the gap 1 1 (Fig. 3b). The catheter is positioned so that the balloon 2 is exactly where it needs to be dilated. The balloon 2 is in the unexpanded state and has a diameter d 1. The diameter d 1 is about as large as the width a of the gap 1 1 in the muscle tissue 10.1, 10.2.

About the one-way valve 4, the balloon 2 is filled with a medium and thereby expanded (Fig. 3c). The diameter of the balloon has the larger diameter d2 in the expanded state. By the pressure of the gap 1 1 is widened. Between the splayed muscle tissue 10.1, 10.2, the gap 1 1 now has the width b.

After successful spreading of the gap 1 1, the one-way valve 4 is separated at position 12 from the catheter 1 (Fig. 3d) and thus the balloon 2 emptied. The diameter of the balloon 2 decreases to d l. The gap 1 1 between the splayed muscle tissue 10. 1, 10. 2 retains the width b, even after removal of the unexpanded balloon catheter 1 (FIG. 3 e).

In Fig. 4a-f, the two-stage spreading of bone tissue is shown. Fig. 4a shows a section of the bone 20.1, 20.2, which has a gap 21 of the width a. The catheter 1 is introduced into the gap 21 with the distal end 6 ahead with the aid of the guide wire 3 (FIG. 4b). The catheter is positioned so that the balloon 2 is exactly at the point that is to be dilated. The balloon 2 is in the unexpanded state and has a diameter d 1. The diameter d 1 is approximately as large as the width a of the gap 21.

About the one-way valve 4, the balloon 2 is filled with a medium and thereby partially expanded (Fig. 4c). The diameter of the balloon initially has the enlarged diameter d2 in the partially expanded state. By the pressure of the gap 21 is widened and has the width b. In this partially expanded state, the catheter is left in the gap 21, so that surrounding tissue, for. B. a bone spanning skin (not shown) can stretch evenly without it breaks. This condition can be maintained for a few days. Due to the pressure-tight one-way valve 4, the pressure within the catheter remains constant. Subsequently, the catheter 1 is filled further via the one-way valve 4 (FIG. 4d). The balloon 2 is further expanded and now assumes the diameter d3. As a result, the gap 21 is also spread further so that it occupies the width c.

If the spreading is completed, the one-way valve 4 is separated at position 12 from the catheter 1 (Fig. 4e) and thus the balloon 2 emptied. The diameter of the balloon 2 decreases to d l. The gap 21 between the splayed bone 20.1, 20.2 retains the width c, even after removal of the unexpanded balloon catheter 1 (Figure 4f).

The two-stage spreading is particularly indicated when z. B. a jaw bone has to be spread. The external gums are relatively firm and can hardly be stretched. If the jawbone widened too much, it would break. But if the gap can be gradually increased, the tissue has the ability to stretch slowly and adapt to the new conditions through growth.

In Fig. 5a-b, the operation of a one-way valve 30 is shown in a catheter according to the invention. The one-way valve 30 is located in the catheter 1. It has in the distal direction 31 a taper 32, which opens into an elastic element 33. The elastic element 33 corresponds to a half-shell whose opening points in the direction of the proximal end 34, while the bottom points in the distal direction 31. If now from the proximal end 34 of a gaseous or liquid medium in the valve 30 is pressed (Fig. 5a), the elastic element 33 is slightly widened, so that between the end of the taper 32 and the elastic member 33 has a passage for the Medium arises. So the balloon catheter can be filled.

If there is some pressure in the balloon catheter (Figure 5b), the elastic element 33 is pressed by this pressure against the end of the taper 32 and the medium can not escape.

Optionally, it is also conceivable to leave the catheter after use in the expanded state in the spread tissue gap. In this case, the balloon is preferably finally filled with a hardening material. However, the catheter can not be easily removed from the widened gap then.

A single lumen catheter has been described. In principle, it is also possible more than a lumen, z. B. provide two lumens. In principle, the catheter can also have a specially formed catheter tip.

The one-way valve may also be designed differently, for. B. as a ball valve. It can be made depending on the tissue to be spread, an individual material selection and material design of the balloon shells. Overall, materials such as metals, alloys, glass, latex, silicone, rubber, plastics, especially PVC, can be used. Catheters can be designed for single or multiple use. Also, the individual coating and / or attachment of colors / markers can be made as needed. In summary, it should be noted that a balloon catheter according to the invention is provided, with which it is possible to spread tissue lying close to each other.

Claims

claims

1. Balloon catheter with a guide wire, suitable for spreading tissue characterized in that it has a pressure-tight closure.

2. Balloon catheter according to claim 1, characterized in that the balloon is provided in the form of a flat disc.

3. Balloon catheter according to one of claims 1 - 2, characterized in that the

Balloon is double-walled.

4. Balloon catheter according to one of claims 1 - 3, characterized in that it can withstand a pressure of up to 40 bar.

5. Balloon catheter according to one of claims 1 - 4, characterized in that the balloon in the expanded state has a length of 10-15 mm and a diameter of up to 10 mm.

6. Balloon catheter according to one of claims 1-5, characterized in that it is made of polyamide, nylon and / or polyester.

7. Balloon catheter according to one of claims 1 - 6, characterized in that it is the pressure-tight closure is a valve.

8. Balloon catheter according to one of claims 1-7, characterized in that the pressure-tight closure is in the proximal region of the balloon catheter at a distance of 0.5 - 1.0 cm to the proximal end.

9. Balloon catheter according to one of claims 1 - 8, characterized in that the pressure-tight closure in the proximal region of the balloon catheter is at a distance of about 5 cm from the balloon.

10. Balloon catheter according to one of claims 1-6, characterized in that it is the pressure-tight closure is a one-way valve.

1 1. Balloon catheter according to claim 10, characterized in that the one-way valve is in the proximal region of the balloon catheter at a distance of 0.5 - 1.0 cm to the proximal end.

12. Balloon catheter according to one of claims 10 - 1 1, characterized in that the one-way valve is located in the proximal region of the balloon catheter at a distance of about 5 cm from the balloon.

13. Use of a balloon catheter according to one of claims 1 - 12 for expanding the nasal passage.

14. Use of a balloon catheter according to claim 13, characterized in that the application takes place daily over a period of several weeks or months.

15. Use of a balloon catheter according to claim 13, characterized in that the daily application is carried out by a patient himself.