Balloon dilatation catheter and balloon thereof

Abstract

The invention relates to a balloon dilatation catheter and a balloon thereof. A balloon for a balloon dilatation catheter, comprising, in the axial direction of the balloon, a balloon body, balloon cones on both sides of the balloon body, and a balloon tip extending from the balloon cones and fixed to the catheter, the balloon body and the balloon cones being composed of a plurality of polymer layers in the radial direction of the balloon, characterized in that the balloon tip comprises a metal.

Description

[0001] This application is a divisional application of the invention patent application 201910775996.6, filed on August 22, 2019, entitled “Balloon dilatation catheter and its balloon”. TECHNICAL FIELD

[0002] The present invention relates to a balloon dilatation catheter and its balloon as an effective dilatation device for percutaneous nephrolithotomy (PCNL) for example. In particular, the present invention relates to a balloon dilatation catheter and its balloon which is easy to identify. BACKGROUND

[0003] Balloon dilatation catheters are currently widely used in many fields, including vascular dilatation, stent placement, and creation of a nephrolithotomy access, etc.

[0004] Two most important properties of balloon dilatation catheters are high burst pressure and distal positionability.

[0005] Distal positionability:

[0006] For a physician, it is important to determine the balloon distal position and the balloon effective site in the case of an accidentally injured patient in order to better treat.

[0007] For example, for percutaneous nephrolithotomy, if it is a blind puncture in the dilatation procedure, this brings a high risk of puncture failure or damage to the kidney parenchyma. Therefore, surgeons urgently need a percutaneous device (especially the distal part) that can be seen with medical imaging methods in order to reduce the risk during the puncture process. In the United States, a measure of visual PCNL is to perform surgery under X-rays so that the device part with X-ray opacity can be seen in the image. However, it is well known that X-ray radiation is harmful to the health of patients and doctors. In addition, the X-ray image actually shows a two-dimensional structure, not a three-dimensional structure, thereby bringing difficulties to confirm the device puncture depth.

[0008] In most balloon dilatation catheters on the market, the distal end is checked by fluoroscopy, not by ultrasound. In China, most doctors prefer to perform surgery under ultrasound guidance. However, it is difficult to position the medical device by ultrasound during the surgery, which can lead to accidental injury to the patient. Some doctors inject ultrasound contrast agent into the balloon body during the surgery in order to detect it. However, the balloon distal end is still not visible.

[0009] Therefore, as more and more PCNLs are needed with the help of ultrasound detection, doctors and medical device manufacturers have noticed a safer medical imaging measure without radiation hazards to patients and doctors. The device with echo reflectivity will be displayed as a bright area, easy to see in a gray-scale ultrasound image.

[0010] Echo-reflective devices appear as bright images in the gray-scale images captured by B-mode ultrasound instruments, allowing the operator to distinguish between the brightness difference between the medical device and the surrounding tissue from the image. The key factor to obtain a bright image is that the probe can receive more backscatter from the device surface. To design a surface with higher backscatter, an interface with a high acoustic impedance difference (Z) should be created between the tissue and the medical device surface so that high-frequency acoustic pulses can be reflected. In theory, the higher acoustic impedance difference at the interface should be such that the more 180° reflection, the better the echo-reflectivity detected. As shown in the equation Z = p x v, Z is the product of the material density and the speed of sound propagation in that material. Since the surrounding tissue and environment of the balloon dilator in the kidney during PCNL is the physiologically saline-filled renal cortex and renal pelvis, the surface of the echo-reflective balloon dilator should have a significant density difference and sound wave propagation speed difference compared to the renal cortex and renal pelvis.

[0011] An effective way is to create a gas-solid interface or a liquid-solid interface, because there is a density difference and a sound speed difference between them. Among various materials, the Z value of air is extremely low, and the Z value of metal is higher than that of any polymer and liquid. Therefore, there are several ways to increase the Z value difference of the interface, such as integrating metal materials, surface patterning treatment, or trapping gas on the device surface.

[0012] U.S. Patent US2014 / 0243845A1 discloses a double-walled balloon catheter including an echo-reflective layer or sleeve made of a mixture of 50%-85% metal material and polymer. U.S. Patent US2013 / 0053770A1 also discloses a balloon catheter having at least two layers, one of which is made of a mixture of 80% tungsten and 20% polymer.

[0013] U.S. Patent US2012 / 0277586A1 discloses an echo-reflective feeding tube having a metal sleeve, multiple internal sleeves, or a band or wrapping wire wound on the tube inside the balloon. US20080058702A1 discloses a tube having a band wound thereon or a band with a deformed surface. The metal piece can also be treated with sandblasting, physical deformation, or machining to have surface roughness to improve echo-reflectivity.

[0014] US2008 / 0097213A1, US20150165160A1, US5967988, US5490521A disclose various patterned surfaces for echo-reflective catheters and biopsy forceps. These patterns include spherical or hemispherical holes on a drainage catheter, recesses with different angles machined on the surface of a cannula with a laser, concave-convex parts or other shapes embedded with metal pieces in the catheter body for coronary sinus perfusion.

[0015] Some examples of echogenicity improvement using gas, bubbles or fluids are as follows. WO 2007 / 102909 A2 discloses an echogenicity blocking balloon by adding a polymer fluid void in the balloon body. US 6106473 and WO 98 / 19713 disclose porous polymer coatings with a large number of gas / non-gas interfaces, constructed by physical agitation and chemical reactions between mixed components that release gas or H2O or simply by the evaporation of volatile solvents. US 6506156 B1 discloses echogenicity coatings with a plurality of pores or glass microsphere particles.

[0016] High burst pressure:

[0017] There are materials that are echogenic under ultrasound. However, it is difficult to combine these materials well with the balloon tip (also called the neck) at high pressures. If the balloon tip is made directly from these materials, the burst pressure of the balloon dilation catheter will be significantly reduced.

[0018] Currently, ultrasound devices and ultrasound technology are not sufficiently developed to detect targets as accurately as X-rays, especially for complex detection environments. Since kidney stones generally have a high ultrasound echogenicity (e.g. percutaneous nephrolithotomy), it is difficult to distinguish the balloon tip from the stone under ultrasound, even if the balloon tip is made from a material with high ultrasound echogenicity.

[0019] Other problems

[0020] In surgery, especially in interventional surgery, it is difficult to measure the size of a diseased area, such as the aneurysm neck size or the kidney stone size. Sometimes, it is important for the physician to know this information.

[0021] In addition, for some surgeries (e.g. percutaneous nephrolithotomy), only a portion of the balloon body is inserted into the patient. The physician cannot easily observe the insertion depth with the naked eye, and thus cannot place the medical device correctly and can cause accidental injury. SUMMARY

[0022] The present invention aims to solve at least one of the above problems.

[0023] According to an aspect of the present invention, a special balloon tip design (including design of shape) helps to identify the balloon tip.

[0024] According to another aspect of the present invention, a special balloon body design also helps to identify the balloon body.

[0025] According to yet another aspect of the present application, the addition of scale markings on the balloon will help the physician to visually gauge the depth of insertion in order to properly place the medical device without causing unintended harm. By placing the balloon with scale markings in close proximity to the diseased area, it will help to gauge the size of the diseased area.

[0026] According to an aspect of the present application, there is provided a balloon for a balloon dilatation catheter, comprising a balloon body, balloon tapers on both sides of the balloon body, and a balloon tip extending from the balloon tapers and fixed to the catheter, the balloon body and the balloon tapers being composed of a plurality of polymer layers in the radial direction of the balloon, characterized in that the balloon tip comprises a metal.

[0027] According to an embodiment, the balloon tip is entirely made of metal.

[0028] According to an embodiment, a plurality of notches are formed on the metal balloon tip.

[0029] According to an embodiment, the balloon tip, the balloon body and the balloon tapers are all composed of a plurality of polymer layers in the radial direction of the balloon, and a metal sleeve or cladding is coated on the balloon tip.

[0030] According to an embodiment, the metal sleeve or cladding is subjected to roughness surface treatment.

[0031] According to an embodiment, the surface treatment is sandblasting, physical deformation or machining.

[0032] According to an embodiment, the balloon tip, the balloon body and the balloon tapers are all composed of a plurality of polymer layers in the radial direction of the balloon, and a plurality of metal hoops are provided on the balloon tip, spaced apart in the axial direction and extending in the circumferential direction.

[0033] According to an embodiment, the surface of the metal balloon tip is subjected to patterning treatment so as to form a rectangular array, a triangular array, a hemispherical array, a diamond array, a cylindrical array or a plurality of parallel grooves extending in the circumferential direction.

[0034] According to an embodiment, the patterned surface of the metal balloon tip is coated with a heat-shrinkable polymer cladding.

[0035] According to an embodiment, the balloon tip, the balloon body and the balloon tapers are all composed of a plurality of polymer layers in the radial direction of the balloon, and the balloon tip is wrapped with metal fibers.

[0036] According to an embodiment, a metal echogenic layer is provided under the outermost polymer layer of the balloon.

[0037] According to an embodiment, the metal echogenic layer comprises a plurality of metal hoops spaced apart in the axial direction and extending in the circumferential direction of the balloon.

[0038] According to an embodiment, the plurality of polymer layers include a polymer adhesive layer in which the metal powder is mixed.

[0039] According to an embodiment, the plurality of polymer layers include a polymer adhesive layer in which the bubbles or pores are formed.

[0040] According to an embodiment, the balloon tip, the balloon body and the balloon taper are each composed of a plurality of polymer layers in the radial direction of the balloon, and the balloon tip is provided with an integral metal ring having a plurality of circumferentially extending through-slots with openings facing in opposite directions, which are spaced apart from each other in the axial direction.

[0041] According to an embodiment, the balloon tip, the balloon body and the balloon taper are each composed of a plurality of polymer layers in the radial direction of the balloon, and the balloon tip is provided with an integral metal ring having a continuous helical through-slot.

[0042] According to an embodiment, the balloon tip, the balloon body and the balloon taper are each composed of a plurality of polymer layers in the radial direction of the balloon, and the balloon tip is provided with an integral metal ring having a plurality of axially arranged windows, each two rows of adjacent windows being circumferentially staggered with respect to each other.

[0043] According to an embodiment, scale marks that reflect ultrasonic waves are printed on the outer surface of the balloon body.

[0044] According to an embodiment, the first scale mark and the scale marks at certain intervals are different in shape from the other scale marks.

[0045] According to an embodiment, the starting position of the scale marks can be at the distal taper of the balloon or at a certain distance from the balloon tip.

[0046] According to another aspect of the present application, there is provided a balloon dilation catheter comprising a balloon as described above and a catheter passing through the interior of the balloon. BRIEF DESCRIPTION OF DRAWINGS

[0047] Other features of the present application will become apparent from the following description of example embodiments, taken together with the drawings.

[0048] Figure 1 A metal tip of an echogenic balloon is shown;

[0049] Figure 2 An echogenic balloon tip with notches is shown;

[0050] Figure 3 An echogenic balloon tip with a metal sleeve or cladding is shown;

[0051] Figure 4 An echogenic balloon tip with surface treatment is shown;

[0052] Figure 5 An echogenic balloon tip with multiple metal banding is shown;

[0053] Figure 6A 、 6B An echogenic balloon tip with various patterned surfaces is shown;

[0054] Figure 7A A cross-sectional view of a prior art balloon is shown, Figure 7B A cross-sectional view of an echogenic balloon with metal banding according to the present application is shown;

[0055] Figure 8 An echogenic balloon tip with multiple echogenic rings is shown;

[0056] Figure 9A Figures 9A (side view), 9B (end view), 9C (perspective view) show one embodiment of an integrated echogenic ring;

[0057] Figure 10A Figures 10A (side view), 10B (end view), 10C (perspective view) show another embodiment of an integrated echogenic ring;

[0058] Figure 11A Figures 11A (side view), 11B (end view), 11C (perspective view) show yet another embodiment of an integrated echogenic ring;

[0059] Figure 12 An example of balloon body sizing is shown;

[0060] Figure 13 Another example of balloon body sizing is shown. DETAILED DESCRIPTION

[0061] In the following, embodiments according to the present application will be described with reference to the accompanying drawings. The echogenic balloon dilation catheter is one example of an echogenic medical device, for example for use in percutaneous nephroscopy. However, it should be noted that the example of an echogenic medical device is not limited to this. Depending on the specific application, the echogenic medical device can be other medical devices known to the skilled person, for example abdominal medical devices, gynecological medical devices, cardiac medical devices, etc.

[0062] The embodiments described below are merely specific examples. However, the present application is not limited to the embodiments described in the specification.

[0063] Generally speaking, as Figure 1As shown, a balloon for balloon dilation catheter is illustrated. The balloon includes a cylindrical balloon body 1, balloon cones 2 on both sides of the balloon body, and a balloon tip (or balloon neck) 3 extending from the cones and fixed to the catheter. The balloon body and balloon cones are joined together by a balloon shoulder 4.

[0064] Echo-reflecting balloon with echo-reflecting tip

[0065] More specifically, this invention relates to the echo-reflecting tip of a balloon. A balloon with an echo-reflecting tip can be identified from surrounding tissues and saline solution injected into the renal pelvis. This invention enhances the acoustic impedance difference between the balloon tip and the surrounding environment.

[0066] Example 1: Echo-reflecting balloon with a metal tip

[0067] like Figure 1 As shown, the distal tip 3 of the balloon, connected to the balloon cone, can be made of a metallic material. Metals have a higher acoustic impedance (Z-value) than organ tissues and organ fluids, which helps to create interfaces with significant Z-value differences. Suitable metals include, but are not limited to, titanium, platinum, and stainless steel, which have excellent biocompatibility and can be used to process the metal tube. The metal tip is attached to the balloon cone by welding or bonding. The metal surface enhances the reflection of sound waves back to the ultrasound probe.

[0068] Further improvements such as Figure 2 As shown, a hemispherical notch with a diameter of 20-50 μm is created on the tip of the balloon by laser ablation (not limited to hemispheres, but can also be other shapes), which will enhance echo reflection because it enhances the backscattering of sound waves.

[0069] Example 2: Echo-reflecting balloon tip with metal sleeve or cladding

[0070] like Figure 3 As shown, the sleeve S or cladding at the balloon tip improves the echo reflectivity of the balloon tip because the difference in acoustic impedance at the interface is increased. The advantage of a metal sleeve is its ease of adhesive bonding. Titanium, platinum, or gold foil with a thickness of 0.01-0.05 mm can be chosen because these metals are flexible enough to cover the balloon tip. All metals with good flexibility can be used. Titanium, platinum, or gold tubing with a wall thickness of 0.02-0.05 mm is preferred because tubing with this wall thickness is rigid enough to form the sleeve.

[0071] US2014 / 0243845A1 and US2013 / 0053770A1 mentioned in the background art both involve polymer and metal powder composite layers, in order to achieve the ultrasonic visualization of the polymer / metal powder composite, a high content of metal powder needs to be added, which leads to the decrease of the ductility of the composite and the difficulty of extrusion molding. In order to take into account the feasibility of extrusion molding, the content of the added metal powder is limited, thus limiting the ultrasonic visualization of the composite layer. The embodiment uses solid metal foil or sleeve on the surface of the balloon tip, which will increase the acoustic impedance difference compared with the polymer, and the manufacturing process is more simplified.

[0072] For US2012 / 0277586A1 mentioned in the background art, the integration of metal on the inner tube is not good for echogenicity, because the sound wave will be reflected or scattered at the first interface reached and the attenuation caused by the balloon wall and the medium filled in the balloon will weaken the reflection on the inner surface. The embodiment provides metal elements at the position of the first interface between the tissue and the balloon tip (i.e. the interface where the ultrasonic wave first reaches), so there is no attenuation caused by other media, so the probability of sound wave reflection is greater.

[0073] Figure 4 Further improvements are shown. The surface of the metal sleeve or cladding is processed to have a roughness of several microns to tens of microns by sandblasting of 60-120 mesh or physical deformation or machining, which can further improve the echogenicity because the backscattering of sound is improved.

[0074] Embodiment 3: Echogenic balloon tip with multiple metal bands

[0075] As shown in Figure 5 , multiple metal bands B bonded on the balloon tip in the winding direction (i.e. the circumferential direction) and spaced apart in the axial direction can improve the echogenicity of the tip, because the interface between the metal and the surrounding environment has a large acoustic impedance difference. The metal can be titanium, platinum, gold, stainless steel or other metals with good biocompatibility. Bonding the bands on the surface of the balloon tip is easy, just bond the metal bands on the balloon tip with glue, whether it is densely glued or intermittently glued. Such a balloon tip can improve the recognizability, because the bonded bands can appear as light and dark intervals in the ultrasonic image. The thickness of the bands can be set to 0.01-0.05mm, the width to 0.7-2mm, and the spacing between the bands to 0.5-2mm.

[0076] Embodiment 4: Echogenic balloon tip with patterned surface

[0077] There is a certain pattern on the surface of the metal balloon tip.

[0078] Furthermore, the patterned balloon tip surface can also be coated with a heat shrinkable polymer coating, which can trap air between the balloon tip surface and the polymer coating due to the air gaps on the patterned surface, forming an air / polymer interface, which has a large acoustic impedance difference, thus increasing echogenicity.

[0079] The surface patterning can be achieved by machining on the final metal balloon tip, including laser lithography, etching, stamping or ball milling after balloon tip shaping. As Figure 6A 、 6B As shown in Fig. 6C, the surface pattern can be of any shape, such as a rectangular array, a triangular array, a hemispherical array, a diamond array, a cylindrical array or a plurality of parallel grooves extending in the circumferential direction, etc.

[0080] US2008 / 0097213A1, US20150165160A1, US5967988, US5490521A mentioned in the background art disclose various patterned surfaces, but do not protect the pattern with a hydrophobic coating or cladding, which prevents tissue fluid or blood from penetrating into the pattern to form a polymer / liquid interface instead of an air / polymer interface, which has much less echogenicity than the air / polymer interface. In particular, US5967988 discloses a complicated method using an additional lumen to protect the pattern, but not a cladding.

[0081] Example 5: Echogenic balloon tip wrapped with metal fibers

[0082] According to this embodiment, the echogenic balloon tip is wrapped with metal fibers. The advantage is that on the one hand an interface between the metal fiber surface and the surrounding tissue is provided, which has a higher acoustic impedance value difference than the interface between the polymer surface and the surrounding tissue, and on the other hand an uneven irregular surface is provided by the irregular arrangement of the metal fiber layer. The fiber cross section is circular or rectangular, and the diameter is 0.05-0.5 mm (circular) or the side length is 0.01-0.05 mm and 0.05-0.25 mm. The metal includes but is not limited to silver, platinum, gold, stainless steel or silver-stainless steel composite. Any metal with good biocompatibility and capable of being extruded into fibers can be used. US20080058702A1 mentioned in the background art discloses a catheter tube wrapped with a winding belt or a belt with a deformed surface, but not on the balloon tip.

[0083] Balloon with echogenic body and cone

[0084] The present invention also relates to an echogenic balloon with an echogenic balloon body and a balloon cone for percutaneous nephroscopy.

[0085] US7309324B2 and US9114236B2 disclose non-compliant fabric balloons. As shown in Figure 7A Figure 1, as an example, the prior art balloon can be composed of multiple layers, including a polymer base layer 10, a polymer adhesive layer 11, a polymer film layer 12, a polymer fiber layer 13, a polymer coating layer 14, and an outermost polymer protective layer 15. However, in the prior art balloon, no echo-reflective element is provided.

[0086] Referring to the following non-limiting examples, according to the present application, an echo-reflective element can be added in the balloon to improve the ultrasonic echo-reflectivity.

[0087] Example 1: Echo-reflective balloon with a metal echo-reflective layer

[0088] As shown in Figure 7B Figure 2, compared with the prior art, a metal echo-reflective layer 16 is added as an additional layer between the polymer coating layer 14 and the outermost polymer protective layer 15. Alternatively, the metal echo-reflective layer can be provided under the outermost layer of the balloon. In this case, the metal echo-reflective layer includes a plurality of hoops spaced axially and extending circumferentially along the balloon. The metal of the hoops can include, but is not limited to, silver, gold, platinum, titanium, or stainless steel, etc. to provide enhanced acoustic wave reflection. Any metal with good biocompatibility can be used. The metal hoops on the balloon body or the tapered portion can be used as scale marks to indicate the balloon position under ultrasonic diagnosis. The hoops on the tapered portion region of the balloon can indicate whether the balloon tapered portion is correctly placed in the renal pelvis, which is important for the surgeon to judge whether the dilation is effective. The width of the hoops on the balloon body is preferably 0.8-3 mm, and the width of the hoops on the tapered portion region of the balloon is preferably 0.8-2 mm.

[0089] Example 2: Mixing metal components in the adhesive between different layers

[0090] According to this embodiment, metal powder can also be mixed in the polymer adhesive, which can increase the density of the entire composite. According to the present application, metal powder, especially silver, titanium, nitinol, gold powder, with a particle size of 1-10 μm and a content of 50-80%, is mixed in the polymer coating layer 14 (also as an adhesive layer) for bonding the polymer fiber layer 13 and the outermost polymer protective layer 15, or in the polymer adhesive layer 11 for bonding the polymer base layer 10 and the polymer film layer 12, which increases the density of the entire balloon and thus enhances the echo-reflectivity of the balloon body or the tapered portion.

[0091] US2014 / 0243845A1 and US2013 / 0053770A1 mentioned in the background art both relate to polymer and metal powder composite layers, in order to achieve ultrasonic visualization of the polymer / metal powder composite, a high content of metal powder needs to be added, which leads to a decrease of the ductility of the composite and makes extrusion molding difficult. In order to make extrusion molding feasible, the content of the added metal powder is limited, which limits the ultrasonic visualization of the composite layer.

[0092] Compared to mixing the echogenic material with the polymer material before balloon extrusion molding and blow molding (as in US2013 / 0053770A1, which discloses the addition of 50-80% tungsten in a polymer matrix), the mixing of the echogenic material in the adhesive has the advantage of being easier.

[0093] Example 3: Echogenic balloon with gas bubbles in the adhesive layer

[0094] According to this embodiment, the expansion / evaporation effect of a poor solvent on a solvent-based adhesive can also be used to create pores in the balloon polymer matrix layer. Specifically, the adhesive layer (e.g. the polymer coating 14 or the polymer adhesive layer 11) can be expanded by the evaporation of a poor solvent, which penetrates into the polymer chains but does not dissolve them. Then, when the solvent evaporates from the adhesive layer, the underlying balloon polymer matrix layer will shrink irregularly to form an irregular (e.g. bumpy) surface, thereby creating echogenic gas pores. The interface between the polymer and the gas pores provides a high acoustic impedance, which helps to improve echogenicity.

[0095] Furthermore, the outermost polymer protective layer 15 can be omitted. In this case, the polymer coating 14 can itself be an adhesive. In this way, it is advantageous to avoid a loss of adhesive properties due to the formation of pores.

[0096] The following are some specific examples according to the above embodiments:

[0097] 1. Example of an echogenic balloon tip

[0098] 1.1 In one example of an echogenic balloon, the balloon tip connected to the balloon cone is made of a metal material, specifically titanium. The titanium balloon tip is bonded to the balloon cone. The large acoustic impedance difference between the titanium balloon tip and the organ tissue builds an interface with large acoustic backscattering on the tip, which increases the brightness of the titanium balloon tip.

[0099] Another way to improve the echogenicity of a metal balloon tip is to laser ablate a hemispherical notch with a diameter of 45 pm on the balloon tip. This also enhances the echogenicity of the balloon tip.

[0100] 1.2 A metal cladding can be placed on the balloon tip. A stainless steel foil of 0.05 mm thickness and a titanium foil are used to cover the balloon tip with the help of an adhesive, enhancing the echogenicity.

[0101] Another way is to sand blast a titanium foil of 0.05 mm thickness and a stainless steel foil of 0.07 mm thickness to create a rough surface with a roughness of 60-120 grit. This rough cladding also enhances the echogenicity of the balloon tip.

[0102] 1.3 A platinum, gold or silver band of 1.0 mm width and 0.038 mm thickness is bonded to the entire circumference of the balloon tip. The entire balloon tip is brightened due to enhanced backscattering of sound waves.

[0103] 1.4 The balloon tip is wrapped with stainless steel-silver composite fiber. A stainless steel-silver composite fiber of 0.076 mm diameter is wrapped as densely as possible on the balloon tip. The wrapped composite fiber helps to greatly improve the echogenicity of the balloon tip.

[0104] 1.5 A patterned balloon tip is manufactured by machining. For example, a groove is machined. As a result, improved tip image recognition is obtained, with brightening in the area of the groove.

[0105] 2. Examples of echogenic balloon body or cone

[0106] 2.1 A metal band is bonded on the balloon body, specifically, a gold band can be bonded on the body or cone of the balloon and cover the entire cone. The gold band is 10 μm thick and 1 mm wide. The echogenicity of the body or cone is improved.

[0107] 2.2 A metal band is bonded on the balloon body, specifically, a gold band can be bonded on the body or cone of the balloon and cover the entire cone. The gold band is 30 μm thick and 1 mm wide. The echogenicity of the body or cone is improved.

[0108] 2.3 A metal band is bonded on the balloon body, specifically, a gold band can be bonded on the body or cone of the balloon and cover the entire cone. The gold band is 10 μm thick and 2 mm wide. The echogenicity of the body or cone is improved.

[0109] 2.4 A metal band is bonded on the balloon body, specifically, a gold band can be bonded on the body or cone of the balloon. The gold band is 10 μm thick and 1 mm wide, with a spacing of about 1 mm between each metal band. The echogenicity of the body or cone is improved.

[0110] 2.5 Adhesion of metal bands on the balloon body, in particular, on the body or the taper of the balloon. The metal bands have a thickness of 30 μm, a width of 1 mm, and a spacing of about 1 mm between the individual metal bands. The echogenicity of the body or the taper is improved.

[0111] 2.6 Adhesion of metal foils on the balloon body, in particular, on the taper or the body of the balloon. The metal foils have a thickness of 0.02 mm and a width of 1 cm. The echogenicity of the taper or the body is improved.

[0112] 2.7 Adhesion of metal foils on the balloon body, in particular, on the taper or the body of the balloon. The metal foils have a thickness of 0.05 mm and a width of 1 cm. The echogenicity of the taper or the body is improved.

[0113] 2.8 Mixing of metal powder into the adhesive between the individual layers. In particular, silver powder having a particle size of 6 μm is mixed into the adhesive in a content of 50 %. The echogenicity of the entire balloon body or the taper is improved.

[0114] 2.9 Addition of a layer of polyurethane adhesive on top of the first polymer layer of the balloon, i.e. the layer which is to be bonded to the second polymer layer. Then, a thin layer of the poor solvent dichloromethane or trichloromethane is applied on top of the polyurethane adhesive and is allowed to evaporate. Due to the formation of pores in the polymer layer below the adhesive layer, the echogenicity of the balloon is improved.

[0115] The above embodiments and examples improve the echogenicity of the balloon tip, the balloon taper or the balloon body.

[0116] According to the present application, the echogenicity of the balloon tip can also be improved by the following further variants.

[0117] The plurality of echogenic rings is mounted on the balloon tip at an axial spacing, which is easy to manufacture and easy to perform ultrasound detection.

[0118] The material from which the echogenic rings are manufactured can be: a metal material which is surface-treated or not surface-treated; an alloy material which is surface-treated or not surface-treated; a polymer material which is surface-treated or not surface-treated and which contains microbubbles; or a combination thereof.

[0119] Similar to the embodiment of Figure 5 , as shown in Figure 8 , the echogenic rings ER are mounted on the balloon tip outside the balloon taper, which helps to ensure a high burst pressure of the balloon, rather than reducing the burst pressure of the balloon.

[0120] Compared with installing a single ring on the balloon tip, since the multiple echo-reflective rings are installed on the balloon tip with certain axial intervals and the surface reflection of the echo-reflective ring material is stronger than that of the balloon tip material, more echo-reflective surfaces can be obtained, thus the ultrasound visibility and detectability of the balloon tip can be enhanced. In addition, the balloon tip material in the gap between the rings helps to capture some air in use, which also helps to enhance the ultrasound visibility of the balloon tip.

[0121] On the other hand, due to the clinical needs, the balloon tip is usually designed to be very small. Therefore, the echo-reflective ring should also be small to be combined with the balloon tip, and should not increase the outer diameter and length of the balloon tip too much. However, it is difficult to combine multiple rings with certain axial intervals to the balloon tip. This problem can be solved by the integrally combined echo-reflective ring.

[0122] (1) As shown in FIGS. 9A (side view), 9B (end view), and 9C (perspective view), the ring body has multiple circumferentially extending through-slots with their opening directions opposite to each other, which are axially spaced apart from each other; Figure 9A (2) As shown in FIGS. 10A (side view), 10B (end view), and 10C (perspective view), the ring body has a continuous helical through-slot;

[0123] Figure 10A (3) As shown in FIGS. 11A (side view), 11B (end view), and 11C (perspective view), the ring body has multiple axially arranged windows, and every two adjacent rows of windows are circumferentially staggered with each other.

[0124] (3) As shown in FIGS. 11A (side view), 11B (end view), and 11C (perspective view), the ring body has multiple axially arranged windows, and every two adjacent rows of windows are circumferentially staggered with each other. Figure 11A For example, the specific design requirements of the integrally combined echo-reflective ring described above can be as follows:

[0125] The ring body entity between the openings is 2 to 5;

[0126] The width of the ring body entity between the openings is 0.3-4 mm;

[0127] The width of the opening is 0.5-2 mm;

[0128] The thickness of the ring is 0.01-2 mm.

[0129] Scale mark

[0130] According to another aspect of the present application, the present application relates to a scale mark printed on the outer surface of the balloon body.

[0131] The scale mark is visible under fluoroscopy or ultrasonography, and is also visible to the naked eye.

[0132] The scale mark is visible under fluoroscopy or ultrasonography, and is also visible to the naked eye.

[0133] ​The scale marks can be used to measure the balloon insertion depth, locate the effective part of the balloon body and measure the diseased area in surgery.

[0134] The gap between each scale mark can be 1-20mm, for example 10mm.

[0135] For different application purposes, the starting position of the scale marks can be from the balloon distal end shoulder to identify the location of the effective part of the balloon. Alternatively, it can also be from a certain distance, for example 5mm, from the balloon tip to determine the catheter insertion depth in the case of accidental injury patients.

[0136] For easy identification, the first scale mark and the scale marks every certain gap, for example 50mm, are different in shape from the other scale marks, for example one is thicker than the other.

[0137] The material of the scale marks can be a metal material with or without surface treatment; an alloy material with or without surface treatment; a polymer material with or without surface treatment and containing micro-bubbles; or a combination thereof.

[0138] Scale mark example 1:

[0139] As shown in Figure 12 , scale marks are added on the outer surface of the balloon body, the first scale mark is located at the distal balloon shoulder, and the last scale mark is located at the proximal balloon shoulder. The gap between each scale mark is 1cm. These scale marks are visible under fluoroscopy or ultrasonography.

[0140] The total number of scale marks is 16. The first, sixth, eleventh and sixteenth scale marks are thicker than the other scale marks.

[0141] In PCNL surgery, the doctor can measure the stone size by comparing it with these scale marks under fluoroscopy or ultrasonography.

[0142] In aneurysm embolization surgery using a balloon catheter, the doctor can measure the aneurysm neck size by comparing it with these scale marks under fluoroscopy or ultrasonography.

[0143] Scale mark example 2:

[0144] As shown in Figure 13 , scale marks are added on the outer surface of the balloon body, the first scale mark is 5mm from the distal tip of the balloon, and the last scale mark is close to the proximal end of the balloon body. The gap between each scale mark is 1cm. These scale marks are visible to the naked eye.

[0145] The total number of scale marks is 12. The first, sixth, and eleventh scale marks are thicker than the other scale marks.

[0146] In a PCNL procedure, a physician needs to place a balloon to a proper position in a body to avoid injury to a patient. Scale marks added on the outer surface of the balloon body can be used as a ruler to record the balloon insertion depth. The physician can insert the balloon and the balloon catheter into the body to a certain depth by naked eye.

[0147] While the present application has been described with reference to example embodiments, it is to be understood that the application is not limited to the disclosed example embodiments, which can be combined in any manner. The scope of the appended claims should be construed to include all such variations as encompassed by the principles of the application.

Claims

1. A balloon for a dilation catheter, comprising, in the axial direction of the balloon: a balloon body; balloon tapers on both sides of the balloon body; and a balloon tip extending from the balloon tapers and fixed to the dilation catheter; wherein the balloon body and the balloon tapers are composed of a plurality of polymer layers in the radial direction of the balloon; wherein the balloon tip comprises metal; and wherein a plurality of notches are formed on the metal balloon tip. The balloon tip is entirely made of metal.

2. The balloon of claim 1, wherein, The outer surface of the balloon body comprises printed scale markers that are capable of reflecting ultrasound waves.

3. The balloon of claim 1, wherein, The first scale marker and every other scale marker are different in shape from the other scale markers.

4. The balloon of claim 3, wherein, The starting position of the scale markers is from the distal end of the balloon or from a distance from the balloon tip.

5. The balloon of claim 4, wherein, 6. A balloon for a dilation catheter, comprising, in the axial direction of the balloon: a balloon body; balloon tapers on both sides of the balloon body; and a balloon tip extending from the balloon tapers and fixed to the dilation catheter; wherein the balloon body and the balloon tapers are composed of a plurality of polymer layers in the radial direction of the balloon; wherein the balloon tip comprises metal; and wherein the balloon tip, the balloon body and the balloon tapers are all composed of a plurality of polymer layers in the radial direction of the balloon, and the balloon tip is provided with a plurality of metal bands that are spaced apart in the axial direction and extend in the circumferential direction. The outer surface of the balloon body comprises printed scale markers that are capable of reflecting ultrasound waves. The first scale marker and every other scale marker are different in shape from the other scale markers.

7. The balloon of claim 6, wherein, The starting position of the scale markers is from the distal end of the balloon or from a distance from the balloon tip.

8. The balloon of claim 7, wherein, 10. A balloon for a dilation catheter, comprising, in the axial direction of the balloon:

9. The balloon of claim 8, wherein, a balloon body; balloon tapers on both sides of the balloon body; and a balloon tip extending from the balloon tapers and fixed to the dilation catheter; wherein the balloon body and the balloon tapers are composed of a plurality of polymer layers in the radial direction of the balloon; wherein the balloon tip comprises metal; and The metal surface of the balloon tip is patterned to form a rectangular array, a triangular array, a hemispherical array, a diamond array, a cylindrical array, or a plurality of parallel grooves extending in the circumferential direction. The patterned surface of the balloon tip is covered with a heat-shrinkable polymer coating. The outer surface of the balloon body comprises printed scale markers that are capable of reflecting ultrasound waves. The first scale marker and every other scale marker are different in shape from the other scale markers.

11. The balloon of claim 10, wherein, The starting position of the scale markers is from the distal end of the balloon or from a distance from the balloon tip.

12. The balloon of claim 10, wherein, The diameter of the plurality of notches is 20 μm to 50 μm.

13. The balloon of claim 12, wherein, ​ 14. The balloon of claim 13, wherein, ​ 15. The balloon of claim 1, wherein, ​

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