Abstract
The present invention relates to a medical device (10), preferably a micro robot for application inside a body, preferably for application inside a human body (2). The medical device (10) includes a body part (11) and a tail part (12). A controlling line (13) is attached to the tail part (12). The controlling line (13) has a tensile strength sufficient to pull back the device from a target location and/or control its velocity and column strength not sufficient to push the medical device (10).
Claims
1.-40. (canceled)
41. A medical device, said medical device comprising: a body part; and a tail part attached to the body part, wherein a controlling line is attached to the device, and wherein a stiffness of the controlling line is not sufficient to move the medical device to a target location.
42. The medical device according to claim 41, wherein the medical device has at least one of: i) a drive for actively moving the device in a direction; and ii) a control member for changing the movement direction within a body by external effects.
43. The medical device according to claim 41, wherein the medical device has a positioning means to determine the position of the medical device in the body.
44. The medical device according to claim 41, wherein the controlling line comprises a transmission cable to transmit one of energy and data.
45. The medical device according to claim 41, wherein the controlling line comprises a material selected from a group of materials consisting of a metal, metal composites, polymers, carbon fibres, graphene, fabric, silk, protein fibres, aramid, and carbon nanotubes.
46. The medical device according to claim 41, wherein the controlling line has a smaller cross-section than the medical device.
47. The medical device according to claim 41, wherein the medical device comprises a material that enables detection by an imaging technique selected from the group consisting of IRM, scanner, echography, X-ray and fluoroscopy.
48. The medical device according to claim 41, wherein the controlling line has an outer diameter of 10 to 1000 m.
49. The medical device according to claim 41, wherein the body part contains a magnetic part.
50. The medical device according to claim 41, wherein the body part contains at least one functional unit.
51. The medical device according claim 41, wherein the body part comprises a compartment configured to store and release a drug.
52. The medical device according to claim 41, wherein the body part contains a transmitter configured to send data from the medical device to a receiver.
53. The medical device according to claim 41, wherein the medical device has a size of 8-2000 m.
54. The medical device according to claim 41, wherein the body part and tail part of medical device comprise a material selected from the group consisting of: metal, plastic, glass, mineral, ceramic, carbohydrate, nitinol, carbon, biomaterial, and a biodegradable material.
55. The medical device according to claim 41, wherein the controlling line is removably attached to the device.
56. The medical device according to claim 55, wherein the controlling line is selectively detachable from the device.
57. The medical device according to claim 41, comprising a first and a second portion of the medical device, wherein the first portion is attached to the controlling line, and wherein the second portion is removably attached to the first portion, wherein the first portion is selectively detachable from the second portion of the medical device.
58. The medical device according to claim 41, comprising exactly one line formed by the controlling line.
59. The medical device according to claim 41, wherein the controlling line is not able to transmit data or energy.
60. The medical device according to claim 41, wherein the controlling line can be bent into a curve with a curvature radius of less than 3 mm without substantial material stress.
61. The medical device according to claim 41, wherein the controlling line is comprises a radiopaque material.
62. The medical device according to claim 61, wherein the radiopaque material is arranged as a separate cable associated with and parallel to the controlling line and/or as a coating on the controlling line.
63. The medical device according to claim 41, wherein the controlling line comprises a hydrophilic surface.
64. The medical device according to claim 41, wherein the controlling line comprises a surface with anti-thrombogeneic properties.
65. The medical device according to claim 41, wherein the controlling line has a surface that is coated with a hydrogel.
66. The medical device according to claim 41, wherein the controlling line is attached to the medical device by at least one of a knot, a clip, a welded connection, an adhesive connection, a mix of materials, and a chemical bond.
67. The medical device according to claim 41, further comprising a hollow tube arranged in parallel with respect to the controlling line.
68. The medical device according to claim 41, further comprising a trigger wire adapted to trigger a function of the device.
69. A method for controlling a medical device comprising the steps of: inserting the medical device, wherein the medical device includes a body part and a tail part; navigating the medical device to a target site without pushing a controlling line; and removing the medical device from the target site, by pulling the controlling line.
70. A system for controlling a medical device comprising a medical device according to claim 49 and a magnetic field generator wherein the medical device is guidable by a magnetic field generated by the magnetic field generator.
71. The system according to claim 70, further comprising a control adapted to control the velocity of the medical device.
72. The system according to claim 70, wherein the system further comprises a coupling element adapted to be coupled to the controlling line in order to connect the coupling element to the device to control its velocity.
73. The system according to claim 70, wherein the control is further adapted to pull in and/or release the controlling line at a controlled velocity.
74. The system according to claim 70, wherein the control comprises a mechanism to control the position of the medical device.
75. A method of controlling a device in a fluid stream, wherein the device comprises a controlling line attached to the device, wherein the velocity of the device is controlled via the controlling line.
76. The method according to claim 75, wherein the velocity is reduced when the device approaches a bifurcation.
77. The method according to claim 75, further comprising a control which automatically controls the velocity of the device.
78. The method according to claim 77, wherein the control automatically detects bifurcations.
79. A medical device, comprising a magnetic head portion attached or attachable to a controlling line, wherein the medical device further comprises a protective layer wherein the protective layer is configured to provide a fluid seal at least of an area of the magnetic head portion attached or attachable to the connecting line.
80. A method of producing a medical device comprising the steps of: providing a magnetic head portion with an attachment area attached or attachable to a controlling line; and providing a protective layer at least partially covering and/or forming an interfacial area between the magnetic head portion and the attachment area.
Description
[0136] Non-limiting embodiments of the invention are described, by way of example only, with respect to the accompanying drawings, in which:
[0137] FIG. 1: Schematic view of a medical device.
[0138] FIG. 2: Schematic view of an insertion site of a human body for the medical device.
[0139] FIG. 3: Schematic view of the medical device with a drive and a control member.
[0140] FIG. 4: Schematic view of the medical device with a positioning means.
[0141] FIG. 5: Schematic view of pulling the medical device with a magnetic field.
[0142] FIG. 6: Schematic view of data and energy transmission through a controlling line of the medical device.
[0143] FIGS. 7a-d: Schematic view of functional units attached to the medical device.
[0144] FIG. 8: Schematic view of a tumor and antibodies delivered to the tumor by the medical device.
[0145] FIG. 9a-9b: different embodiments of a medical device that is releasably attached to a controlling line.
[0146] FIG. 10: a schematic view of a system according to the invention.
[0147] FIG. 11: an alternative embodiment of a medical device according to the invention.
[0148] FIGS. 12a-12b: schematically a method according to the invention.
[0149] FIGS. 13a-13b: schematically an alternative method according to the invention.
[0150] FIG. 14: schematically a medical device inside a vessel filled with blood.
[0151] FIGS. 15a-15f: different embodiments of a controlling line with an associated element in a cross-sectional view.
[0152] FIG. 16: schematically a method step of producing a medical device.
[0153] FIG. 17a-17d: schematically different embodiments of magnetic head parts.
[0154] FIG. 18a-18d: schematically different embodiments of medical devices with a protective layer.
[0155] FIG. 1 shows a schematic view of a medical device 10 comprising a body part 11 and a tail part 12. A controlling line 13 is attached to the body part 12. The controlling line 13 is used to pull the medical device 10.
[0156] FIG. 2 shows a schematic view of an insertion site 20 of a human body 2 for the medical device 10. The heart 1 is connected to a bloodstream. The blood stream comprises different types of blood vessels 6 such as aorta 3, veins 4 and capillaries 5. The medical device 10 is inserted into the blood vessel 6 at the insertion site 20. Therefore the blood vessel 6 is perforated by a catheter 22 at the insertion site 20. The medical device 10 is inserted into a blood stream B. The blood stream B is carrying the medical device 10 through the blood vessel until the medical device reaches a site of interaction 25 (FIG. 5). At any time the medical device 10 is connected to the controlling line 13 and can be pulled back to the site of insertion 20.
[0157] FIG. 3 shows the medical device 10 with the controlling line 13 in a blood vessel 6. The medical device 10 has a drive 15 and a control member 16, to control the drive. The drive 15 actively moves the medical device 10 in a direction. The control member 16 modifies the action of the drive 15. The control member 16 can invert the rotation direction of the drive 15 or adjust its speed.
[0158] FIG. 4 shows the medical device 10 with the controlling line 13 in a blood vessel 6. The medical device 10 has a positioning means 17. The positioning means 17 emits a signal 19, which is received by a receiver 18. Based on the signal 19, the receiver 18 calculates the position of the medical device 10.
[0159] FIG. 5 shows a schematic view of the blood vessel 6 with the medical device 10. The medical device 10 is transported by the blood stream B and attached to the controlling line 13. A magnetic field generator 23 is generating a magnetic field 21 at the application site 25. The body part 11 of the medical device has a magnetic part 14, which is attracted by the magnetic field 21. At the application site 25 the medical device 10 stays in place, held by the magnetic field 21 against force of the blood stream B. After performing any kind of action the magnetic field generator 23 is switched off and the magnetic field 21 collapses. The medical device is removed against the force of the blood stream B by pulling at the controlling line 13.
[0160] FIG. 6 shows a schematic view of the medical device 10. The controlling line 13 comprises an energy transmission cable 30 and a data transmission cable 31. The energy transmission cable transmits energy to sensors 40 and a compartment 41. The sensors send data through the data transmission cable 31. As an alternative the energy transmission cable 30 and the data transmission cable 31 can be integrated into the same cable. This cable is used to transport energy to and data to and from the medical device through the controlling line 13.
[0161] FIG. 7a-d shows a schematic view of the medical device 10 with attachable functional units 51. In FIG. 7a the functional unit 51 is a propeller to move the medical device 10 in a forward or reverse direction along a longitudinal axis through the device. FIG. 7b shows a medical device 10 where the functional unit 51 is a caterpillar. The caterpillar is used to move the medical device 10 onto a tissue site. In FIG. 7c the functional unit 51 of the medical device 10 is a drill. The drill can be used to perforate a tissue and create an opening to move across physical barriers. In FIG. 7d the functional unit 51 of the medical device 10 is a hook. The hook can be used to hold the medical device 10 in place or to drag an object or material, when the medical device 10 is recaptured.
[0162] FIG. 8 shows a schematic view of a tumor site 63. The tumor cells 61 have a bigger size and a faster replication cycle than the normal cells 60. The medical device 10 is guided to the tumor site and carries tumor specific antibodies 62 in the compartment 41. At the tumor site 63 the medical device 10 releases the tumor specific antibodies 62. The antibodies bind to the tumor cells and induce an immunotherapeutic process. After releasing the antibodies 62 the medical device 10 is removed from the tumor site 63 by pulling on the controlling line 13.
[0163] FIG. 9a shows another embodiment of a medical device 10 according to the invention. The medical device 10 comprises a tail part 12 and a body part 11 which are configured as separate elements. The body part 11 and the tail part 12 are connected via a connection mechanism 26. The robot is attached to a single controlling line 13 that is adapted to control the robot's velocity in a fluid stream. The connection mechanism 26 is selectively deactiveatable such as to detach the body part 11 from the tail part 12 by applying an electrical current. The connection mechanism 26 comprises a ferrous material that disintegrates when an electrical current flows through it due to electrolysis. The connection mechanism 26 therefore releases the body part 11 of the medical device 10.
[0164] FIG. 9b shows an alternative embodiment where a selectively detachable connection mechanism 26 directly connects the controlling line 13 and the medical device 10. The medical device 10 is thus releasable from the controlling line 13 through an electrical detachment similar to the ones described above. The connection mechanism 26 comprises a noble metal part, which comprises a noble metal such as a platinum alloy, that is attached to a ferrous part. By applying an electrical current, the ferrous part acts as an anode and the ferrous ions dissolve in the surrounding liquid and thus disintegrate the ferrous part such as to release the medical device. Additionally or alternatively, the connection mechanism 26 could be degraded by an increase in temperature induced by any known method such as a localized heating element or ultrasound.
[0165] FIG. 10 schematically shows a system 60 according to the invention. The system 60 comprises a control 61 that is connected to a first end 13 of the controlling line 13. A second end 13 of the controlling line 13 is attached to the medical device 10.
[0166] A magnetic field generator 23 is presently included in the system 60 in order to guide or steer the medical device 10 in a fluid stream (not shown).
[0167] FIG. 11 shows an alternative embodiment of a medical device 10. The medical device 10 comprises a controlling line 13 for velocity control. The medical device 10 is additionally connected to a transmission cable 31 that transmits data to and from the medical device 10 from and to an external computer (not shown). It would also be possible to transmit electrical energy to the medical device 10 using the cable 31.
[0168] FIG. 12a schematically shows a first step of a method according to the invention. A microrobot 10 floats in a vessel 6 in the vicinity of a bifurcation B. According to a treatment plan, the microrobot 10 shall be directed to a target site 25 and thus needs to be steered in the correct direction at the bifurcation B. Thus, the microrobot 10 is slowed down by the controlling line 13 until it comes to a stop at a position upstream of the bifurcation B. The microrobot 10 is now at a fixed position along the streaming direction of the blood, but the microrobot 6 may still perform some limited movements as the controlling line is typically a flexible element.
[0169] FIG. 12b shows that the microrobot 10 is pushed towards a target side of the bifurcation B leading to the target site 25. Once the microrobot 10 is positioned, the controlling line 13 may again be released at a controlled velocity such that the microrobot is carried on by the blood again.
[0170] FIG. 12c shows the robot moving in the direction of the target site 25 in the blood stream and with substantially the same velocity as the blood flow. When the target site is reached, the robot may be stopped by holding the controlling line.
[0171] FIGS. 13a-13b show an alternative method to control a medical device 10 in a vessel 6. The method is similar to the one schematically shown in FIGS. 12a-12c, but differs in that the microrobot 10 is never completely stopped.
[0172] FIG. 13a thus shows a microrobot 10 attached to a controlling line in a vessel 6. As the microrobot 10 approaches a bifurcation B, the microrobot 10 is slowed down via the controlling line 13.
[0173] FIG. 13b shows how in parallel to the slowdown, a magnetic field 21 is employed to steer the microrobot 10 in a direction of a target site 25.
[0174] FIG. 13c shows the microrobot 10 floating again in the blood vessel.
[0175] FIG. 14 shows schematically a microrobot 10 in a vessel system 6 with several bifurcations B, B, B, B. A catheter C is employed to bring the microrobot 10 to a vessel system 6 to be treated. The microrobot's 10 velocity is controlled by controlled release or pull on a controlling line 13 that is attached to the microrobot 10, in particular in the vicinity of the bifurcations B, B, B, B. The controlling line 13 is made of silk and coated with a hydrogel. For this reason, it is mechanically flexible and can bend to adapt to the vessel system 6. The hydrogel surface additionally reduces the thrombogeneicity of the controlling line 13 and reduces friction on the vessel walls.
[0176] FIG. 15a shows a controlling line 13 made of a single material, presently Kevlar, in a cross-sectional view.
[0177] FIG. 15b shows a controlling line 13 with a radiopaque line 71 arranged in parallel to a longitudinal direction of the controlling line 13. The radiopaque line 71 consists of a composite of a biocompatible polymer and barium sulphate. It is therefore visible in X-ray imaging. Additionally or alternatively, platinum or gold rings could be associated and connected with the controlling line.
[0178] FIG. 15c shows a controlling line 13 with an anti-thrombogeneic hydrogel coating 72 on the surface of the controlling line. Presently, the hydrogel is based on PEG. The hydrogel could however include any material selected from a group of ELPs, HEMA, PHEMA, polyvinylpyrrolidone, PMA (or other methacrylate/methacrylic acid-based polymers), agarose, hyaluronic acid, methyl cellulose, elastin, and chitosan.
[0179] FIG. 15d shows a controlling line 13 with a transmission cable 30 for energy transmission configured as a separate element arranged in parallel to the longitudinal direction of the controlling line 13. The transmission line consists of gold and can transmit electrical energy. Alternatively, the transmission line could also consist of platinum, or any conductive metal (such as copper) coated with at least one of gold and platinum. The transmission line could also, additionally or alternatively, be used to transmit data.
[0180] FIG. 15e shows an alternative embodiment of a controlling line 13, wherein a transmission cable 31 for data transmission is arranged inside the controlling line 13. Additionally or alternatively, the transmission line 13 may also transmit energy.
[0181] FIG. 15f shows an alternative embodiment of a controlling line 13, wherein a hollow tube 73 is arranged in parallel and outside the controlling line 13. The hollow tube is adapted for suction action in order to take tissue samples or to remove fluid and/or cells from the target area.
[0182] FIG. 16 shows schematically a method step of producing a medical device. A magnetic head part 100 with a south pole 101 and a north pole 102 is brought in operable contact with a magnet 101 such as to orient the magnetic head 100 part with respect to a magnetic field of the magnet 101. Thus, a controlling line 13 can be selectively attached to the magnetic head part 100 on its south pole 101. Alternatively, the controlling line 13 may be attached to the north pole 102 or any other location of the magnetic head part 100. Usage of a magnet 101 facilitates the attachment because the orientation of the magnetic head part 100 with respect to its magnetic properties may be known.
[0183] FIG. 17a shows an embodiment of a magnetic head part 100. The magnetic head part 100 comprises a plurality of magnetic particles 104 arranged within a polymer matrix 105.
[0184] One possible method to produce such an embodiment is described in the following. Demagnetized hard ferromagnetic particles may be incorporated into a polymer matrix. Then, the particles are magnetized. Additionally or alternatively, soft ferromagnetic particles, superparamagnetic particles or ferrimagnetic particles may be incorporated into a polymer matrix. The particles, with a diameter between 5 nm to 5 m, preferably between 30 nm to 100 nm can be incorporated by emulsion, molding or prilling. The polymer matrix can be bioresorbable (PLLA, PLGA, PDO, PCL for example) or non-bioresorbable such as silicone, PDMS, polyurethane.
[0185] Furthermore, the magnetic head part 100 comprises an outer layer 103 which comprises tracking members (not visible) in the form of radiopaque particles. The magnetic head part 100 has a diameter in the range of 300 m to 1.5 mm, preferably 400 m to 800 m.
[0186] FIG. 17b shows another embodiment of a magnetic head part 100 which comprises a substantially spherical magnetic material 106 with a hollow tube 107. The hollow tube may be used for transmission or suction of fluid, in particular to create a vacuum, and/or deliver a liquid, a gas, a therapeutic solution, to move a therapeutic tool in the front of the device and/or microrobot or to guide optical or electric cables through . The hollow tube 107 has a diameter between 70 m to 200 m, preferably 0.1 mm and spans substantially across a central region of the magnetic head part 100. It would be conceivable, however, to arrange a hollow tube at a position which is laterally displaced from the central portion. The hollow tube 106 may be at least partially curved and/or straight. The magnetic head portion 100 had a diameter of 1.1 mm.
[0187] FIG. 17c shows another embodiment of a magnetic head portion 100 configured as a Janus particle. Here, the Janus particle comprises on portion of magnetic material 106 and a portion comprising an active material 108.
[0188] Additionally or alternatively, the Janus particles can be made of two different magnetic materials. For example, FePt and Fe.sub.2O.sub.3. In such a configuration, the magnetic particles exhibit a hard ferromagnetic behavior (FePt) and ferrimagnetic behavior (Fe.sub.2O.sub.3). In another configuration, one side is made of magnetic material and the other side is made of non-magnetic material. Nonmagnetic material can be metals such as NiTi or polymers such as polyurethane. The non-magnetic material can be used to setup or activate the therapeutic tool of the microrobot. As example, the non-magnetic material can be made of NiTi which will change its shape under a stimuli such as an increase of temperature which could be induced with an electric current for example.
[0189] FIG. 17d shows yet another embodiment of a magnetic head portion 100 comprising a magnetic material 106 configured as an outer shell. The inner core 109 may be any other suitable material which may be magnetic or non-magnetic. For example, the outer layer can be made of Fe.sub.3O.sub.4 with a thickness of 200 m and the inner core can be made of FePt with a diameter of 400 m. Alternatively, the outer layer can be made of a mixture of Fe.sub.2O.sub.3 and FePt with a thickness of 300 m and the inner core can be made of PDMS with a diameter of 400 m. This design contributes to reduce the rigidity of the microrobot.
[0190] It will be understood that any of the features described in the context of the FIGS. 17a-17d may be used for any devices disclosed herein, in particular combined with any other features disclosed herein.
[0191] FIG. 18a shows an embodiment of a medical device 10 comprising a magnetic head portion 100 and a controlling line 13 attached thereto. Here, the controlling line 13 is attached to an attachment area 101 which comprises a cyanoacrylate adhesive that provides attachment between the magnetic head part 100 and the controlling line 13. Furthermore, a protective layer 111 configured as a layer of epoxy resin is arranged on the magnetic head part 100. Here, the protective layer 111 is continuously arranged on the entire surface of the magnetic head part 100 and the attachment area 110. The controlling line 13, which is attached to the attachment area 110, protrudes through the protective layer 111. Thus, the protective layer seals the magnetic head part 100 from fluids that may be present in the surrounding of the medical device 10 and reduces corrosion effects. It will be understood that the protective layer may, in some alternative embodiments, not be in contact with the controlling line 13 and only cover partially the attachment area 110 in a circumferential area (see FIGS. 18b and 18d), which would still provide a fluid seal of the magnetic head part 100.
[0192] FIG. 18b shows a different embodiment of a medical device 10 which is similar to the embodiment of FIG. 18a. The medical device 10 comprises a magnetic head part 100 which is attached to a controlling line 13 via an attachment area. Here, the magnetic head part 100 is partially coated with a protective layer 110 which is formed as a band and covers an interface 112 between the attachment area 110 and the magnetic head part 100. The configuration of the protective layer shown here may provide sufficient corrosion reduction, in particular over a typical treatment time frame, such as to provide secure attachment of the controlling line 13 to the magnetic head part 100. However, advantageously, less material is needed to provide the protective layer 111, which may be more economical, more environmentally friendly, and may reduce the overall size of the medical device 10. It will be understood that the protective layer 111 in the embodiment shown here does not provide a fluid seal of the entire magnetic head part 100 as a proximal portion 113 and a central portion of the magnetic head part 100 are not covered by the protective layer 111. However, the interface 112 is fluid-sealed by the protective layer 111. It would be conceivable to also cover, in some alternative embodiments, the central portion 114 and the proximal portion 113 with protective layer 111 such as to provide a fluid-seal of the entire magnetic head part 100.
[0193] This approach allows to have two different coatings: one for securing the attachment of the controlling line with the magnetic part and one for the functionalization of the head of the microrobot. For example, a therapeutic tool such as a tank for a drug or a hook can be attached to the uncovered magnetic surface with a resin layer.
[0194] Alternatively, the magnetic head could also be made of two parts which are closed together with the controlling line. With such design, the controlling line is embedded into the magnetic part. For example, one magnetic part has a female design and the other part has a male design. Both parts have an area for the controlling line. The controlling line is compressed between the two parts during the assembly.
[0195] FIG. 18c shows yet another embodiment of a medical device 10. Here, a magnetic head portion 100 is continuously coated with a protective layer 111 on its entire surface. An attachment area 110, which comprises a cyanoacrylate glue, is arranged on an outside surface on the protective layer 111. The controlling line 13 is attached to the magnetic head part 100 via the attachment area 110. Such a configuration may provide particularly secure attachment of the controlling line 13.
[0196] FIG. 18d shows yet another embodiment of a medical device 10. The embodiment shown here is similar to the embodiment shown in FIG. 18b. Here, the protective layer 111 is also formed as a band that covers an interface 112 between the attachment area 110 and the magnetic head part 100. However, the band is configured to cover more than 50% of the surface of the magnetic head part 100. The attachment area 110, which is formed by a hot melt adhesive, is not covered by the protective layer 111. A proximal area 113 of the magnetic head part 100 is not covered by the protective layer 111. Here, the controlling line 13 is attachable to the attachment area 110 by heating the hot melt adhesive and securing the controlling line 13 thereto.
[0197] It will be understood that the features of the embodiments of FIGS. 18a-18d may be freely combined. In particular, any magnetic head portion 100 may be attached or separately attachable to a controlling line 13. Similarly, any of the configurations of the protective layer shown in FIGS. 18a-18d may be used in combination with any other embodiment or feature shown here or further disclosed herein.
