Orthotic force minimally invasive intervention treatment system and tissue young's modulus identification method

Abstract

Based on the correction force minimally invasive interventional treatment system, including guide limiting mechanism, puncture needle, correction force guide needle device and screw slide, the sliding part of the screw slide moves along the X axis direction, the sliding part of the screw slide is provided with a force sensor, and the correction force guide needle device is arranged on the force sensor;Based on the correction force minimally invasive interventional treatment system and the tissue Young's modulus identification method, the problem that the tissue Young's modulus is difficult to obtain in the operation under the clinical environment is solved, the identified tissue modulus value is brought into the established needle tip flexural deformation prediction model, the needle tip flexural value is obtained, and the prediction accuracy of the model is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of minimally invasive medical instruments, and particularly relates to a minimally invasive interventional therapy system based on a correction force and a tissue Young's modulus identification method. BACKGROUND

[0002] Minimally invasive interventional therapy technology is a new surgical medical technology that has developed rapidly in recent years. Under the guidance of medical imaging equipment, precision instruments such as special needles, catheters and guide wires are introduced into the human body to diagnose and locally treat body lesions. It has obvious advantages over traditional surgical therapy, such as small trauma, safety and ease of operation, accurate positioning, fast effect, few side effects and low cost, and is therefore favored by the contemporary medical community and widely used in live tissue pathological examination, local tissue and organ drug targeted delivery and surgery. Minimally invasive medical treatment will become an inevitable trend in the development of future surgical clinical medicine. During the treatment, the needle tip and body of the puncture needle (which belongs to a semi-flexible needle) interact with the punctured tissue. The interaction between the needle and the tissue will cause the needle to deform and flex during the puncture process, resulting in the needle tip failing to reach the planned position and low puncture accuracy. The doctor needs to pull out the puncture needle and re-puncture, causing secondary injury to the patient.

[0003] With the development of robot technology, robot-assisted doctor puncture technology has developed rapidly. By establishing a needle-tissue interaction model, a needle deflection deformation prediction model is obtained. However, the current prediction model for the deflection of the puncture needle due to the dominant effect of force mainly focuses on the needle deflection deformation prediction model based on the mechanical model. This method needs to use the tissue Young's modulus as the model input parameter. Since the puncture process is limited or interferes with the standard surgical procedure of each operation, it may be difficult to obtain the Young's modulus in the clinical environment before or during the surgery, which seriously affects the prediction accuracy. SUMMARY

[0004] The purpose of the present application is to provide a minimally invasive interventional therapy system based on a correction force and a tissue Young's modulus identification method to solve the technical problem that the intraoperative tissue Young's modulus is difficult to obtain in the current clinical environment, which seriously affects the prediction accuracy.

[0005] To achieve the above-mentioned purpose, the technical scheme of the minimally invasive interventional therapy system based on a correction force and the tissue Young's modulus identification method provided by the present application is as follows:

[0006] The minimally invasive interventional therapy system based on a correction force comprises a guide limiting mechanism, a puncture needle, a correction force guide needle device and a lead screw sliding table. The sliding part of the lead screw sliding table moves along the X-axis direction. A force sensor is installed on the sliding part of the lead screw sliding table, and the correction force guide needle device is arranged on the force sensor.

[0007] The puncture needle sequentially passes through the guide limiting mechanism and the correction force guide needle device, and the guide limiting mechanism is used for limiting movement of the puncture needle in the Z-axis direction; when the sliding part of the lead screw sliding table drives the correction force guide needle device to move along the X-axis direction, the correction force guide needle device applies a correction force to the puncture needle, the correction force is the correction force, and the direction of the correction force is along the X-axis;

[0008] The X-axis and the Z-axis are perpendicular to each other.

[0009] Further, the correction force guide needle device has a through hole, and a protruding ring is arranged on the inner wall of the through hole of the correction force guide needle device, and the correction force is applied to the puncture needle by the protruding ring.

[0010] The tissue Young's modulus identification method based on the correction force minimally invasive interventional treatment system comprises the following steps.

[0011] S1, sequentially passing the puncture needle through the guide limiting mechanism and the correction force guide needle device, then operating the puncture needle to penetrate the target tissue along the Z-axis direction, and stopping the penetration when the penetration distance is ds;

[0012] S2, starting the lead screw sliding table, moving the correction force guide needle device along the X-axis direction by the lead screw sliding table, so that the correction force guide needle device applies a correction force F1 to the puncture needle body, the correction force F1 is measured by a force sensor, and the distance u(c2) of the sliding part of the lead screw sliding table moving along the X-axis direction, i.e. the offset distance of the puncture needle at point B, is recorded, the puncture needle is offset, and the puncture needle body compresses the surrounding tissue;

[0013] S3, calculating the total energy of the puncture needle-tissue system and the work done by the correction force on the puncture needle.

[0014] Compared with the prior art, the beneficial effects of the present application are as follows: the correction force minimally invasive interventional treatment system and the tissue Young's modulus identification method provided by the present application solve the problem of difficulty in obtaining the in-situ tissue Young's modulus in a clinical environment, the identified tissue Young's modulus value is brought into the established needle tip deflection deformation prediction model to obtain the needle tip deflection value, and the prediction accuracy of the model is improved. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 The schematic diagram of the correction force minimally invasive interventional treatment system and the tissue Young's modulus identification method provided by the present application is shown in the figure.

[0016] Marked with 1, guide limiting mechanism; 2, force sensor; 3, lead screw sliding table; 4, correction force guide needle device; 5, puncture needle; Fl, correction force; the offset distance of the puncture needle at point B; l, needle length; ds, distance when stopping penetration; u0(z), position of the puncture needle before applying the correction force; u(z), position of the puncture needle after applying the correction force. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0018] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0019] The present invention will be further described in detail below with reference to the embodiments.

[0020] Specific embodiments of the minimally invasive interventional therapy system based on corrective force and the method for identifying Young's modulus of tissue provided by this invention:

[0021] like Figure 1 As shown, in this embodiment, the minimally invasive interventional treatment system based on corrective force includes a guide limiting mechanism 1, a puncture needle 5, a corrective force guide needle 4, and a screw slide 3. The sliding part of the screw slide 3 moves along the X-axis direction, and a force sensor 2 is installed on the sliding part of the screw slide 3. The corrective force guide needle 4 is set on the force sensor 2.

[0022] The puncture needle 5 passes sequentially through the guide limiting mechanism 1 and the corrective force guide 4. The guide limiting mechanism 1 is used to limit the movement of the puncture needle 5 in the Z-axis direction. When the sliding part of the lead screw slide 3 drives the corrective force guide 4 to move in the X-axis direction, the corrective force guide 4 applies force to the puncture needle 5. This applied force is a corrective force, and the direction of the corrective force is along the X-axis. The X-axis and Z-axis mentioned above are perpendicular to each other.

[0023] The corrective force guide 4 has a through hole, and a raised ring 41 is provided on the inner wall of the through hole of the corrective force guide 4. The corrective force is applied to the puncture needle 5 by the raised ring 41.

[0024] The method for identifying tissue Young's modulus using the aforementioned minimally invasive interventional treatment system based on corrective force includes the following steps:

[0025] S1. Pass the puncture needle 5 through the guide limiting mechanism 1 and the corrective force needle guide 4 in sequence, and then operate the puncture needle 5 to advance along the Z-axis direction beyond the target tissue. Stop the needle advance when the needle advance distance is ds.

[0026] S2, start the lead screw sliding table 3, drive the correction force guide 4 along the X-axis direction by the lead screw sliding table 3, so that the correction force guide 4 exerts a correction force F1 on the needle body of the puncture needle 5, the correction force F1 is measured by the force sensor 2, and the distance u(c2) of the sliding part of the lead screw sliding table 3 moving along the X-axis direction is recorded, that is, the offset distance of the puncture needle 5 at point B, the puncture needle 5 is offset, and the puncture needle 5 compresses the surrounding tissue;

[0027] S3, calculate the total energy of the puncture needle-tissue system and the work done by the correction force on the puncture needle 5.

[0028] The steps of calculating the total energy of the system and the work done by the correction force on the puncture needle 5 in step S3 are as follows:

[0029] The tissue is modeled as a linear elastic spring, where the spring stiffness is the stiffness per unit length squared. During the application of the correction force F1 to the tissue, the application of the correction force F1 is kept uniform, and the puncture needle-tissue system is in equilibrium. To obtain the Young's modulus K of the tissue, the principle of conservation of energy is applied, that is, the work done on the puncture needle-tissue system must be equal to the potential energy in the system.

[0030] The correction force guide 4 does work on the puncture needle-tissue system, which is related to the value of the correction force F1 measured by the force sensor 2, and the deflection deformation model uk(z) of the needle relative to the correction force Fl before the application of the correction force Fl (the needle deflection value is assumed to be zero).

[0031] It should be noted that in this document, terms such as "comprise", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or inherent to such a process, method, article or device.

[0032] Although embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A system for minimally invasive intervention based on corrective force, characterized in that, The device comprises a guide limiting mechanism, a puncture needle, a correction force guide needle device and a screw sliding table. The sliding part of the screw sliding table moves along the X-axis direction. The sliding part of the screw sliding table is provided with a force sensor. The correction force guide needle device is arranged on the force sensor. The puncture needle passes through the guide limiting mechanism and the correction force guide needle device in sequence. The guide limiting mechanism is used for limiting the movement of the puncture needle along the Z-axis direction. When the sliding part of the screw sliding table drives the correction force guide needle device to move along the X-axis direction, the correction force guide needle device applies force to the puncture needle. The force is a correction force, and the direction of the correction force is along the X-axis. The X-axis and the Z-axis are perpendicular to each other.

2. The orthokinetic microinvasive intervention system according to claim 1, characterized in that, The correction force guide needle device has a through hole. The inner wall of the through hole of the correction force guide needle device is provided with a protruding ring. The correction force is applied to the puncture needle by the protruding ring.

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