Medical devices and methods for performing surgical procedures inside the body

Abstract

The present invention relates to a medical device 10, preferably a microrobot for intracorporeal operation, preferably a microrobot for operation within the human body 2. The medical device 10 includes a body portion 11 and a tail portion 12. Attached to the tail portion 12 is a retrieval string 13. The retrieval string 13 has sufficient tensile strength to retract the device, but not sufficient column strength to push the medical device 10.

Description

Technical Field

[0001] The present invention relates to medical devices and methods for performing surgery inside the body. In some non-limiting examples, the medical device relates to a micro-robot for working inside the human body.

Background Art

[0002] Minimally invasive procedures, also known as minimally invasive surgery, are surgical techniques that require only a minimal incision size, thus having a short wound healing time required and reducing the trauma risk in patients. Specific tools have been designed for minimally invasive surgery, such as catheters, fiber optic cables, grippers, and forceps on long sticks or small video cameras.

[0003] A limitation in minimally invasive surgery is that the surgeon may have to use tools that require a technique with little movement, which can be extremely tiring in long surgeries.

[0004] A further development in the field of minimally invasive surgery is robotic-assisted surgery or robotic surgery. In this case, a robotic system is used to assist the surgeon in surgical procedures. Multiple robotic arms allow the surgeon to perform minimally invasive surgery while operating the robotic arms, for example, using a joystick. However, the surgery is still somewhat invasive, creating internal and external wounds that take time to heal.

[0005] A further development is micro-robots that are injected into the human body for diagnosis, surgery, or treatment. These micro-robots can be used to measure the blood glucose level of diabetic patients in real time to diagnose or monitor the disease, or to deliver drugs to a target location, such as a tumor (by Ornes, PNAS, 2017). These micro-robots are small devices, with sizes ranging from a few millimeters to a few microns.

[0006] Edd et al. disclose a surgical microrobot intended to provide a novel method for navigating through the human ureter to break up kidney stones (IEEE Proceedings, 2003). Peyer et al. disclose an electrophoretic microrobot with an artificial flagellar structure for navigating through fluids of varying viscosities (IEEE, 2012). Due to their size, microrobots cannot accommodate batteries and motors. A common method for guiding microrobots to a target location is to control them using an external magnetic field, often incorporating magnetic materials. The Multiscale Robotics Laboratory at ETH Zurich disclosed a tetherless microrobot with a diameter of 285 μm for ophthalmic surgery. [Overview of the project] [Problems that the invention aims to solve]

[0007] The small size of these microrobots limits their ability to move against the flow of fluids such as blood. While magnetic fields can guide or stop robots, their strength may not be sufficient to move a robot against the opposing flow of blood.

[0008] The object of the present invention is to alleviate one or more of the above-mentioned problems, in particular, to provide a medical device, preferably a microrobot, that is easy to manufacture and use. Some embodiments have the additional advantage of being highly reliable and thus enabling recovery savings. [Means for solving the problem]

[0009] According to the present invention, the above problem is solved by the features described in the characteristic portion of the independent claim.

[0010] The present invention relates to a medical device. The medical device may be a microrobot for use in the blood vessels of the body. In particular, the medical device or microrobot may be suitable for operation inside the human body. The medical device includes a body and a tail. The device may have a retrieval cord attached to the tail, which may be adapted to pull the medical device back from a first position. In one embodiment, the retrieval cord may have insufficient rigidity to move the medical device to a target position.

[0011] The first position may, in particular, be the target site of a medical device. The retrieval cord may have sufficient tensile strength to pull the medical device back, but not sufficient column strength to push the medical device against forces generated by static or dynamic bodily fluids. Therefore, the cord can be formed thin enough to be easily inserted into the main duct.

[0012] As used herein, the term “string” is intended to cover any structure that performs the task of pulling a device, and, if applicable, may also perform other non-limiting tasks.

[0013] The medical device may be adapted for injection into the body, particularly into the human body. The tail and, optionally, the body may have a larger cross-section than the retrieval cord. The medical device may be retracted mechanically or manually. Such a retrieval cord allows the medical device to be pulled through an opposing fluid flow, such as blood flow. This pulling motion may be for fine-tuning the position or for retrieving the medical device. In particular, the device may be equipped with a handle for the retrieval cord.

[0014] The retrieval cord may have a length configured to extend from the medical device to the insertion site of the medical device. One embodiment of the present invention relates to a system comprising a port and a medical device, wherein the retrieval cord extends from the tail portion to the port.

[0015] The retrieval string may be thread, especially a soft thread. Effectively, the thread can be bent. One advantage is that such medical devices can be smaller in size than known catheter devices, and therefore require only a small incision.

[0016] The medical device can be released into the body's blood vessels, transported by fluid flow to a target site within the vessels, and retrieved in a simple manner. The device may be repositioned by loosening or pulling the retrieval cord.

[0017] A medical device preferably includes at least one drive mechanism for actively moving the device in a certain direction, and a control member for controlling and preferably modifying the movement of the medical device within the body. The medical device may move through the flow of bodily fluids and / or move across tissues.

[0018] The drive mechanism can be any function that moves the medical device. Possible embodiments include propellers, wheels, tracks, flagella, legs, hooks, or magnetic drive mechanisms for external steering. A control member can move, steer, or stop the device by an external effect, such as a signal. The control member can adjust the speed or direction of rotation of the drive mechanism, and thus control its position. The drive mechanism may allow the medical device to travel through sharply curved blood vessels.

[0019] The medical device preferably includes a positioning means for determining the position of the medical device within the body. The positioning means emits a signal, which is received by a receiver. The receiver then calculates the position of the medical device. This signal may be a radio wave, a radioactive tracer, a sound wave, Bluetooth®, or any other wireless signal. In an alternative embodiment, the positioning means may include sensors for measuring different environmental parameters such as temperature, pH, redox potential, salt concentration, viscosity, pressure, potential, gas concentration, radioactivity, and / or metabolic level. The positioning means transmits the measured parameters to the receiver, which then calculates the position of the medical device. The measured parameters may also be used for environmental analysis.

[0020] The medical device retrieval lanyard preferably comprises a transmission cable for transmitting energy and / or data, particularly optical or electrical signals, to and from the medical device. The transmission cable may also include two separate cables, namely, a cable for delivering energy and data and a cable for receiving data. Alternatively, the transmission cable may be a single cable for transmitting energy, data, and images, acting as the retrieval lanyard.

[0021] The retrieval string may contain or be made of biocompatible materials. Preferably, the retrieval string is made of metal, especially copper, polymer, carbon fiber, or nylon. ,silk The material comprises, or substantially consists of, one of the group of materials comprising, and carbon nanotubes, particularly graphene.

[0022] These materials are biocompatible and have longitudinal strength sufficient to pull a medical device. Further, the materials described above preferably withstand degradation for at least several hours or days and can eventually degrade if the device is lost, which ensures that the medical device can be removed at any time as needed. Further, these materials withstand environmental influences in the body such as various pH or oxidative stress.

[0023] The medical device preferably includes materials detectable by imaging techniques, such as by MRI, CT scanner, ultrasound, X-ray or fluoroscopy.

[0024] Thereby, the position of the device can be determined at any time during the procedure. If necessary, the position can also be tracked, especially in real time. Since the guidance of the medical device can become complicated depending on parameters such as the viscosity of the fluid or the external pressure due to the flow of body fluids, a continuous position confirmation process is beneficial.

[0025] The medical device can be particularly suitable for blood vessels, especially arteries or veins. Other application sites can be the urethra or ureter. The retrieval string of the medical device preferably has an outer diameter of 10 - 1000 μm, more preferably 50 - 200 μm.

[0026] The main body part may include a magnetic part. This magnetic part can be used to induce the medical device by interaction with an external magnetic field. The magnetic part may be a core made of a magnetic material or containing magnetic materials, magnetic microparticles or nanoparticles in a matrix or coating.

[0027] The medical device preferably includes at least one functional unit such as a clamp, scalpel, drill, hook, stent, leg, caterpillar, propeller, detonator, camera or sensor, or a drug release component.

[0028] The functional unit may be attachable to a medical device. The functional unit can be used to move the medical device over tissue or through a fluid. It can also be used to attach the medical device to a tissue site, or to open a passage within an occluded opening, or to create a new opening. Alternatively, the functional unit can also be used to collect data from the body environment.

[0029] This proposed device is particularly suitable for removing thrombi in arteries, occluding aneurysms, or delivering drugs to tumors. The detonating device may also be able to open thrombi.

[0030] The functional unit may be activatable. In some embodiments, the functional unit is activated by a magnetic field, or in certain embodiments, by an electromagnetic wave. This enables, for example, the controlled release of drugs. The functional unit may be activatable by energy, such as an electrical signal.

[0031] The medical device preferably comprises a reservoir for storing and releasing drugs. The reservoir can be used to administer the drug to a specific application site. For example, tumor cells can be locally treated with a toxic drug. Thus, the medical device is used to transport a toxic drug to the application site and release it there. The controlled release of drugs also enables the possibility of time-limited drug administration. The medical device can be inserted, guided to the application site, and waited until the scheduled release time of the drug. It is also possible to control the delayed release of two different drugs, such as an active drug and an enzyme that inactivates the drug.

[0032] The medical device preferably comprises a transmitter for transmitting data from the medical device to a receiver, particularly via a retrieval cord.

[0033] The retrieval string may be adapted to transmit energy, thereby transmitting data obtained by sensors within the medical device.

[0034] The device may also be adapted to receive energy via a retrieval string and / or transmit data obtained by sensors within the medical device, particularly within the main body, via the retrieval string. In additional or alternative embodiments, the medical device or retrieval string may include a wireless transmitter and / or wireless receiver for transmitting and / or receiving energy or data.

[0035] The medical device preferably has a size of 8 to 2000 μm, preferably 50 to 1000 μm, and more preferably 200 to 500 μm. This size may be the length, diameter, or longest dimension of the medical device.

[0036] The main body and / or tail portion of the medical device preferably contains materials such as metal, plastic, glass, mineral, ceramic, carbohydrate, nitrinol, carbon, biomaterial, or biodegradable material.

[0037] The present invention further provides a method for performing surgical procedures in the body, preferably in the human body. In the first step, a medical device is inserted into the body. The medical device is then navigated to a site of interaction without pressing a retrieval cord. In particular, the medical device is inserted upstream of the target site. Fluid flow may also carry the medical device to the target site. The medical device may be positioned by loosening or pulling a retrieval cord.

[0038] The medical device may perform one or more actions at one or more locations. The medical device is removed from the body by pulling a retrieval string.

[0039] The present invention further provides a system for controlling a medical device. The system comprises a medical device, preferably one of the medical devices described above, and a magnetic field generator. The medical device is then guided by a magnetic field generated by the magnetic field generator.

[0040] The external magnetic field generator produces a magnetic field with a gradient of 0.1 to 20 T / m, preferably 0.2 to 1 T / m. Once the medical device is inserted into the body, the magnetic field can be used to guide the medical device to the application site. Thus, the medical device is moved, stopped, or steered by the magnetic field, especially while floating in a flow of bodily fluids. The medical device remains attached to the retrieval lanyard throughout.

[0041] In a further embodiment, the medical device may have magnetic anisotropy. This allows the medical device to be oriented by a magnetic field.

[0042] The present invention further relates to a medical device, preferably a microrobot, for operation within the body, preferably within the human body.

[0043] Non-limiting embodiments of the present invention will be described as merely illustrative with reference to the accompanying drawings. [Brief explanation of the drawing]

[0044] [Figure 1] This is a schematic diagram of a medical device. [Figure 2] This is a schematic diagram of the insertion sites for medical devices in the human body. [Figure 3] This is a schematic diagram of a medical device comprising a drive unit and a control unit. [Figure 4] This is a schematic diagram of a medical device equipped with an alignment mechanism. [Figure 5] This is a schematic diagram illustrating how a medical device is pulled by a magnetic field. [Figure 6] This is a schematic diagram illustrating the transmission of data and energy via a retrieval lanyard for medical devices. [Figure 7a]This is a schematic diagram of a functional unit attached to a medical device. [Figure 7b] This is a schematic diagram of a functional unit attached to a medical device. [Figure 7c] This is a schematic diagram of a functional unit attached to a medical device. [Figure 7d] This is a schematic diagram of a functional unit attached to a medical device. [Figure 8] This is a schematic diagram of a tumor and antibodies delivered to the tumor by a medical device. [Modes for carrying out the invention]

[0045] Figure 1 is a schematic diagram showing a medical device 10 comprising a main body 11 and a tail portion 12. Tail section A retrieval string 13 is attached to 12. The retrieval string 13 is used to pull the medical device 10.

[0046] Figure 2 is a schematic diagram showing the insertion site 20 of the medical device 10 in the human body 2. The heart 1 is connected to the blood flow. The blood flow includes different types of blood vessels 6, such as the aorta 3, veins 4, and capillaries 5. The medical device 10 is inserted into the insertion site 20 of the blood vessel 6. Thus, the blood vessel 6 is perforated at the insertion site 20 by the catheter 22. The medical device 10 is inserted into the blood flow B. The blood flow B carries the medical device 10 through the blood vessel until the medical device reaches the interaction site 25 (Figure 5). The medical device 10 can be attached to a retrieval tether 13 at any time and retrieved back to the insertion site 20.

[0047] Figure 3 shows a medical device 10 with a retrieval cord 13 inside a blood vessel 6. The medical device 10 has a drive unit 15 and a control member 16 for controlling the drive unit. The drive unit 15 actively moves the medical device 10 in a certain direction. The control member 16 modifies the action of the drive unit 15. The control member 16 can reverse the direction of rotation of the drive unit 15 or adjust its speed.

[0048] Figure 4 shows a medical device 10 with a retrieval cord 13 inside a blood vessel 6. The medical device 10 has an alignment means 17. The alignment 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.

[0049] Figure 5 is a schematic diagram showing a blood vessel 6 together with a medical device 10. The medical device 10 is transported by blood flow B and attached to a retrieval string 13. A magnetic field generator 23 generates a magnetic field 21 at the application site 25. The main body 11 of the medical device 10 has a magnetic part 14, which is attracted by the magnetic field 21. At the application site 25, the medical device 10 remains in place, held against the force of blood flow B by the magnetic field 21. After some action is performed, the magnetic field generator 23 is turned off and the magnetic field 21 collapses. The medical device is removed against the force of blood flow B by pulling the retrieval string 13.

[0050] Figure 6 shows a schematic diagram of the medical device 10. The retrieval cord 13 comprises an energy transmission cable 30 and a data transmission cable 31. The energy transmission cable 30 transmits energy to the sensor 40 and compartment 41. The sensor transmits data via the data transmission cable 31. Alternatively, the energy transmission cable 30 and the data transmission cable 31 can be integrated into the same cable. Using this cable, energy is transported to the medical device via the retrieval cord 13, and data is transported to and from the medical device.

[0051] Figures 7a to 7d are schematic diagrams showing a medical device 10 with attachable functional units 51. In Figure 7a, the functional unit 51 is a propeller for moving the medical device 10 forward or backward along the longitudinal axis of the device. Figure 7b shows a medical device 10 where the functional unit 51 is a caterpillar. The caterpillar is used to move the medical device 10 over a tissue site. In Figure 7c, the functional unit 51 of the medical device 10 is a drill. The drill can be used to drill holes in tissue and create openings for movement over physical barriers. In Figure 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 retrieving the medical device 10.

[0052] Figure 8 is a schematic diagram showing a tumor site 63. Tumor cells 61 are larger in size and have a faster replication cycle than normal cells 60. The medical device 10 is guided to the tumor site and carries tumor-specific antibodies 62 in compartment 41. The medical device 10 releases the tumor-specific antibodies 62 at the tumor site 63. The antibodies bind to tumor cells and induce the immunotherapy process. After releasing the antibodies 62, the medical device 10 is removed from the tumor site 63 by pulling the retrieval string 13.

Claims

1. A medical device (10) for use in a blood vessel, adapted to be carried by the flow of blood within the blood vessel, wherein the medical device (10) Main body (11) and Including the tail section (12), The retrieval string (13) is attached to the device. The retrieval string (13) has sufficient tensile strength to pull back the medical device (10) but not sufficient column strength to push the medical device (10) to the target position. The main body comprises a magnetic section, which can be used to steer the medical device by interaction with an external magnetic field while the medical device is floating in the blood flow, and the medical device can be positioned by loosening or pulling the retrieval string. Furthermore, the medical device (10) is characterized by including at least one functional unit (51) for opening a passage in a blocked opening so that the medical device is applied to remove thrombus formation in the blood vessel.

2. The medical device (10) according to claim 1, characterized in that it has alignment means (17) for determining the position of the medical device (10) within the body.

3. The medical device (10) according to claim 1 or 2, characterized in that the retrieval string (13) comprises a transmission cable (30, 31) for transmitting energy and / or data.

4. The medical device (10) according to any one of claims 1 to 3, characterized in that the recovery string (13) contains one material from the group of materials consisting of metal, polymer, carbon fiber, graphene, cloth, silk, protein fiber, and carbon nanotube.

5. The medical device (10) according to any one of claims 1 to 4, characterized in that the retrieval string has a smaller cross-section than the medical device.

6. The medical device (10) according to any one of claims 1 to 5, characterized in that it includes a material that enables detection by at least one of the imaging techniques, including MRI, scanner, ultrasound, X-ray, and fluoroscopy.

7. The medical device (10) according to any one of claims 1 to 6, characterized in that the retrieval string (13) has an outer diameter of 10 to 1000 μm.

8. The medical device (10) according to any one of claims 1 to 7, characterized in that the main body (11) comprises a compartment (41) configured to store and release a drug (62).

9. The medical device (10) according to any one of claims 1 to 8, characterized in that the main body (11) includes a transmitter (17) configured to transmit data from the medical device to a receiver (18).

10. The medical device (10) according to any one of claims 1 to 9, characterized in that it has a size of 8 to 2000 μm.

11. The medical device (10) according to any one of claims 1 to 10, characterized in that the main body (11) and tail (12) of the medical device (10) include a material selected from the group consisting of metal, plastic, glass, mineral, ceramic, carbohydrate, nitinol, carbon, biomaterial, or biodegradable material.

12. A system for controlling a medical device (10) according to any one of claims 1 to 11, comprising a medical device (10) adapted to be transported by fluid flow within the blood vessels of the body and a magnetic field generator (23), The system is characterized in that the medical device (10) is controllable by a magnetic field (21) generated by the magnetic field generator (23).

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