Water-temperature-driven foldable guide tube for flexible surgical instrument

Abstract

The invention relates to the field of natural orifice surgical instruments, in particular to a water-temperature-driven foldable guide tube of a flexible surgical instrument, which can be used in natural orifice surgery to protect a human orifice from being stabbed by the surgical instrument. The guide pipe takes a woven framework as a base body, an elastic sleeve is wrapped outside the woven framework, the guide pipe has folding and unfolding characteristics, the woven framework is formed by weaving capillary tubes with built-in shape memory alloy wires, the capillary tubes are connected with an external water source, and when hot water is introduced into the capillary tubes, the shape memory alloy wires are heated to expand so as to support the elastic sleeve; the guide tube is in a large-diameter unfolding state, so that sufficient operation space is provided for surgical instruments; when cold water is introduced, the shape memory alloy wire is cooled and softened, and the elastic sleeve presses the woven framework back to a small-diameter folded state, so that the operation difficulty of inserting and withdrawing the woven framework into and out of a human body cavity is reduced.

Description

Technical Field

[0001] The invention relates to the field of natural cavity surgical instruments, and in particular to a foldable guide tube of a flexible surgical instrument driven by water temperature. Background Art

[0002] Natural orifice surgery refers to a new minimally invasive technique that uses surgical tools to enter the body cavity through natural openings in the human body, such as the esophagus and anorectal cavity, to complete the surgical operation. The diameter of the flexible surgical instruments used in the operation is often larger (only slightly smaller than the diameter of the cavity) after integrating cutting and suturing tools. Therefore, when the flexible surgical instruments enter the body cavity, they are prone to puncture tissues and cause discomfort to the patient.

[0003] The use of a foldable instrument guide tube is a key step in solving the above-mentioned problems. The foldable instrument guide tube can smoothly enter the body cavity from the natural cavity in a slender state, and then radially expand to present a large contour state, which is relatively fixed with the cavity. While providing an entry path for subsequent flexible instruments, it also forms a physical barrier between the surgical instruments and the cavity, reducing the risk of tissue puncture caused by surgical instruments entering the human body and ensuring the safety of patients.

[0004] One solution is to use a foldable instrument guide tube made of a braided structure, but the braided structure lacks an effective bidirectional foldable drive method, that is, the guide tube can actively expand from a small diameter state to a large diameter state through external stimulation, and can also fold from a large diameter state to a small diameter state under changing stimulation conditions. In order to solve the above problem, this case was born. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the above-mentioned background technology and provide a water temperature driven flexible surgical instrument foldable guide tube, which should have a bidirectional folding and unfolding driving function to achieve bidirectional conversion between a small diameter state and a large diameter state.

[0006] The technical solution of the present invention is:

[0007] A foldable guide tube for a flexible surgical instrument driven by water temperature, characterized in that it includes a braided skeleton and an elastic sleeve tightly wrapping the braided skeleton; the braided skeleton is a tubular mesh structure woven from capillaries with built-in shape memory alloy wires; the inner hole of the capillary serves as a water flow channel, and the shape memory alloy wire passes through the water flow channel.

[0008] The number of the capillary tube is one; the two ends of the capillary tube are respectively a water inlet and a water outlet.

[0009] The inner diameter of the capillary is greater than the outer diameter of the shape memory alloy wire.

[0010] The capillary tube is formed by connecting a plurality of capillary short tubes in sequence through elastic joints.

[0011] The elastic joints are arranged at the distal end and the proximal end of the braided skeleton; the capillary short tubes extend in a spiral manner along the forward direction and the reverse direction respectively and are interlaced and woven with each other to form a tubular mesh structure.

[0012] The elastic sleeve is made of an elastic film.

[0013] A folding and unfolding method, using the water temperature driven flexible surgical instrument to fold and unfold the guide tube, comprises the following steps:

[0014] 1) Connect the capillary tube to the water pump;

[0015] 2) The water pump passes cold water into the capillary. The stiffness of the shape memory alloy wire decreases after being cooled, and the elastic sleeve compresses the braided skeleton to shrink inward, and the guide tube presents a flexible small-diameter folded state;

[0016] 3) The guide tube is inserted into the human body cavity; the water pump continuously flows cold water into the capillary tube;

[0017] 4) The water pump passes hot water into the capillary tube. The stiffness of the shape memory alloy wire increases after being heated, and the braided skeleton expands outward to overcome the resistance of the elastic sleeve, and the guide tube presents a rigid large-diameter expanded state;

[0018] 5) Place surgical instruments into the guide tube to perform surgical operations; the water pump continuously passes hot water into the capillary tube;

[0019] 6) After the operation is completed, the surgical instruments are removed, and the water pump passes cold water into the capillary again. The stiffness of the shape memory alloy wire decreases after being cooled, and the elastic sleeve compresses the braided skeleton to shrink inward, and the guide tube presents a flexible small-diameter folded state;

[0020] 7) The guide tube is removed from the human body cavity.

[0021] The beneficial effects of the present invention are:

[0022] 1. The guide tube of the present invention can be actively folded and unfolded, which can reduce the difficulty of inserting it into the body cavity. It is suitable for narrow and complex working environments such as natural cavity surgery, and can provide a barrier for the body cavity, reduce the risk of subsequent instrument puncture, and ensure the safety of the patient;

[0023] 2. The guide tube of the present invention is driven to fold and expand by circulating hot and cold water, with high driving efficiency, short response time, and safety and reliability;

[0024] 3. The guide tube of the present invention is based on a braided skeleton and has good flexibility, and can be inserted into the body cavity conveniently, safely and smoothly. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1It is a three-dimensional structural schematic diagram of the foldable guide tube of the flexible surgical instrument of the present invention.

[0026] Figure 2 It is a schematic diagram of the enlarged structure of the distal end of the braided skeleton of the present invention.

[0027] Figure 3 It is a schematic diagram of the enlarged structure of the proximal end of the braided skeleton of the present invention.

[0028] Figure 4 It is a schematic diagram of the bending deformation of the braided skeleton of the present invention.

[0029] Figure 5 It is a schematic diagram of the large-diameter expanded state of the braided skeleton of the present invention.

[0030] Figure 6 It is a schematic diagram of the three-dimensional structure of the capillary of the present invention.

[0031] Figure 7 It is a schematic diagram of the present invention that drives the shape memory alloy wire to deform by water temperature heat.

[0032] Reference numerals:

[0033] Water inlet 1-1, water outlet 1-2, capillary 1-3, shape memory alloy wire 1-4, elastic sleeve 1-5, distal end 1-6, proximal end 1-7, power plug 6-1, water pump 6-2, button 6-3. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0035] like Figure 1 As shown, a water temperature driven flexible surgical instrument can fold and unfold the guide tube, including an inner layer of a braided skeleton and an outer layer of an elastic sleeve 1-5.

[0036] The braided skeleton is a tubular mesh structure, and includes capillaries 1-3 and shape memory alloy wires 1-4. The elastic sleeve is made of an elastic film, and the elastic sleeve tightly wraps the braided skeleton.

[0037] The number of the capillary tube is one, and the capillary tube is formed by connecting a plurality of capillary short tubes in sequence through elastic joints. The two ends of the capillary tube are respectively a water inlet 1-1 and a water outlet 1-2, and the entire braided skeleton has only one water inlet and one water outlet for connecting cold and hot water sources.

[0038] The elastic joints (omitted in the figure) are arranged at the distal end 1-6 and the proximal end 1-7 of the braided skeleton. These capillary short tubes extend in a spiral manner along the forward and reverse directions respectively, and the capillary short tubes are interlaced and arranged as a whole to form a tubular network structure.

[0039] The braided skeleton has good flexibility and its bending shape is as follows Figure 4 As shown in the figure, it can achieve large curvature bending, so it is easy to insert into the human body cavity when it is in a small diameter folded state. The braided skeleton also has radial folding performance and can undergo radial expansion deformation under the drive of the shape memory alloy wire. Its radial expansion shape is as follows Figure 5 shown.

[0040] The shape memory alloy wire passes through the inner hole of the capillary, that is, it extends into the capillary from the water inlet and extends out through the water outlet. The inner diameter of the capillary is larger than the outer diameter of the shape memory alloy wire, so a certain space is left between the inner hole of the capillary and the shape memory alloy wire as a water flow channel. Since the shape memory alloy wire is built into the capillary, the shape memory alloy wire also forms a tubular mesh structure similar to a braided skeleton.

[0041] The shape memory alloy wire has shape memory capability. When cold water passes through the water flow channel, the temperature of the shape memory alloy wire decreases, and the wire is in a martensite phase, with low rigidity and relatively softness. The elastic sleeve exerts radial extrusion force on the braided skeleton, so that the guide tube presents a flexible small-diameter folded state. When hot water passes through the water flow channel, the temperature of the shape memory alloy wire increases, and the wire is converted into an austenite phase, presenting a memorized shape with high rigidity. Therefore, the braided skeleton overcomes the resistance of the elastic sleeve and expands outward, and the guide tube presents a rigid large-diameter expanded state.

[0042] like Figure 7 As shown, a folding and unfolding method, using the water temperature driven flexible surgical instrument to fold and unfold the guide tube, comprises the following steps:

[0043] 1) Connect the capillary tube to the water pump; connect the power plug 6-1 of the water pump 6-2 to the power supply, and after the water pump is started, hot water and cold water can be pumped out respectively to thermally drive the guide tube;

[0044] 2) The water pump is controlled by button 6-3 to pass cold water into the capillary. The stiffness of the shape memory alloy wire decreases (becomes softer) after being cooled, the elastic sleeve compresses the braided skeleton to shrink inward, and the guide tube presents a flexible small-diameter folded state;

[0045] 3) Insert the guide tube into the human body cavity until the distal end of the guide tube reaches the lesion; at this time, the water pump continuously passes cold water into the capillary to keep the guide tube in a small diameter folded state;

[0046] 4) The water pump is controlled by button 6-3 to pass hot water into the capillary. The stiffness of the shape memory alloy wire increases (hardens) after being heated, and the braided skeleton expands outward to overcome the resistance of the elastic sleeve. The braided skeleton stretches the elastic sleeve, and the guide tube presents a rigid large-diameter expanded state, so it is close to the inner wall of the entire cavity. The elastic sleeve also has a heat preservation effect to prevent the heat loss of water;

[0047] 5) Place surgical instruments into the guide tube for surgical operation; since the guide tube has formed a physical barrier between the surgical instruments and the cavity, the risk of surgical instruments piercing the inner wall of the cavity can be reduced; during the operation, the water pump continuously passes hot water into the capillary to keep the guide tube in a large diameter expanded state;

[0048] 6) After the operation is completed, the surgical instruments are removed, and the water pump is controlled by button 6-3 to pass cold water into the capillary. The stiffness of the shape memory alloy wire decreases (becomes softer) after being cooled, and the elastic sleeve compresses the braided skeleton to shrink inward, and the guide tube presents a flexible small-diameter folded state;

[0049] 7) Move the guide tube out of the human body cavity.

[0050] It can be seen from the above embodiments that the present invention not only obtains higher human-machine contact safety based on flexible capillaries, but also ensures the feasibility of hydrothermal drive, and has the advantages of high safety, flexible structure, compact size, rapid recovery, easy drive adjustment, simple design, etc. Hot water drive is easier to improve the performance of the guide tube.

[0051] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A flexible surgical instrument foldable guide tube driven by water temperature, characterized in that: It comprises a braided skeleton and an elastic sleeve (1-5) tightly wrapping the braided skeleton; the braided skeleton is a tubular mesh structure braided by using capillaries (1-3) with built-in shape memory alloy wires (1-4); the inner hole of the capillary serves as a water flow channel, and the shape memory alloy wires (1-4) pass through the water flow channel.

2. The foldable guide tube of a water temperature-driven flexible surgical instrument according to claim 1, characterized in that: The number of the capillary tube is one; the two ends of the capillary tube are respectively a water inlet (1-1) and a water outlet (1-2).

3. The foldable guide tube of a water temperature driven flexible surgical instrument according to claim 2, characterized in that: The inner diameter of the capillary is greater than the outer diameter of the shape memory alloy wire.

4. The foldable guide tube of a water temperature driven flexible surgical instrument according to claim 3, characterized in that: The capillary tube is formed by connecting a plurality of capillary short tubes in sequence through elastic joints.

5. The foldable guide tube of a water temperature driven flexible surgical instrument according to claim 4, characterized in that: The elastic joints are arranged at the distal end (1-6) and the proximal end (1-7) of the braided skeleton; the capillary short tubes extend in a spiral manner in a forward direction and a reverse direction respectively and are interlaced and woven with each other to form a tubular network structure.

6. The foldable guide tube of a water temperature driven flexible surgical instrument according to claim 5, characterized in that: The elastic sleeve is made of an elastic film.

7. A folding and unfolding method, using the foldable guide tube of the water temperature driven flexible surgical instrument according to any one of claims 1 to 6, comprising the following steps: 1) Connect the capillary tube to the water pump; 2) The water pump passes cold water into the capillary. The stiffness of the shape memory alloy wire decreases after being cooled, and the elastic sleeve compresses the braided skeleton to shrink inward, and the guide tube presents a flexible small-diameter folded state; 3) The guide tube is inserted into the human body cavity; the water pump continuously flows cold water into the capillary tube; 4) The water pump passes hot water into the capillary tube. The stiffness of the shape memory alloy wire increases after being heated, and the braided skeleton expands outward to overcome the resistance of the elastic sleeve, and the guide tube presents a rigid large-diameter expanded state; 5) Place surgical instruments into the guide tube to perform surgical operations; the water pump continuously passes hot water into the capillary tube; 6) After the operation is completed, the surgical instruments are removed, and the water pump passes cold water into the capillary again. The stiffness of the shape memory alloy wire decreases after being cooled, and the elastic sleeve compresses the braided skeleton to shrink inward, and the guide tube presents a flexible small-diameter folded state; 7) The guide tube is removed from the human body cavity.

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