Probe type sensor matched with alternating magnetic field for puncture navigation

Abstract

The invention relates to a probe type sensor matched with an alternating magnetic field to carry out puncture navigation, which is characterized in that a magnetic core coil is used as a sensitive element, a magnetic core is made of a high-permeability amorphous wire material, and two coils with an included angle are used for realizing the measurement of the rolling angle of a probe; an FPC (Flexible Printed Circuit) or an ultrathin PCB (Printed Circuit Board) with a bonding pad is used as a substrate, and two coils are arranged on two sides of the substrate; a metal capillary tube is used as a probe shell, and a sensitive element is completely packaged in the capillary tube; a sheet-shaped plastic handle is used, and lead switching is carried out in the handle; an ROM chip is arranged in the connector to record mapping parameters and other information. The method can provide high-sensitivity measurement signals for six-degree-of-freedom space positioning and tracking, has good sensitivity and robustness, and provides data support for high-precision puncture navigation.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and particularly to a probe-type sensor for puncture navigation in cooperation with an alternating magnetic field. Background Art

[0002] Based on the electromagnetic field positioning principle, an electromagnetic tracking and positioning system can achieve non-contact and high-precision spatial positioning and tracking, and provide the position and attitude data of a positioning sensor in real time. When using a 5-degree-of-freedom positioning sensor, the spatial position coordinates and heading and pitch angle data of the sensor can be obtained. When using a 6-degree-of-freedom sensor, the roll angle data of the sensor can also be obtained. By arranging the sensor on objects such as medical devices and tools, the pose measurement and tracking of the object to be measured can be realized.

[0003] Electromagnetic positioning technology is currently widely used in the medical field to achieve the positioning of various instruments and implants in the human body and assist in completing surgical operations. One type of application is for puncture positioning, such as for drainage, biopsy, etc. For example, in intracranial hematoma puncture navigation, electromagnetic positioning technology is applied during the placement of a puncture tube. The navigation device tracks and positions the guiding needle with a navigation element in the puncture tube in a graphical manner, and then displays the position and path of the puncture tube during the operation in real time, assisting clinicians to accurately and safely place the puncture tube at the intracranial hematoma affected area of the patient, improving the treatment efficiency and quality of the patient.

[0004] The basic sensitive element of an electromagnetic positioning sensor is usually in the form of a coil, which converts the alternating magnetic field generated by a transmitter into an alternating voltage, and after amplification and conditioning, the pose of the sensor is calculated. In medical applications, in addition to general parameters such as sensitivity, there are also strict requirements for the size and biocompatibility of the sensor. Summary of the Invention

[0005] In view of the above analysis, the present invention aims to disclose a probe-type sensor for puncture navigation in cooperation with an alternating magnetic field; it can provide a high-sensitivity measurement signal for the positioning and tracking in a 6-degree-of-freedom space, and provide data support for high-precision puncture navigation.

[0006] The present invention discloses a probe-type sensor for puncture navigation in cooperation with an alternating magnetic field, including a probe, a handle, a connecting cable, and a connector. The probe includes: a needle body housing, a magnetic sensitive element, a substrate, and a coil sleeve; wherein,

[0007] The end of the needle body housing is connected to the handle, and the top end is a puncture positioning point, which adopts a thin-walled capillary structure and is made of a low-magnetic metal material;

[0008] The magnetic sensitive element is two magnetically core coils with the same parameters and a high aspect ratio, which are installed on the substrate at a fixed angle;

[0009] The coil sleeve is wrapped around the outside of the magnetic core coil and the substrate, and is used to fixedly install the magnetic core coil and the substrate together at the central position near the puncture positioning point inside the needle body housing.

[0010] The relative positions, directions, included angles, and installation positions of the two magnetic core coils are stored in the sensor as calibration data for positioning during puncture.

[0011] Furthermore, a ROM chip is arranged inside the connector, and the calibration data including the relative positions, directions, included angles, and installation positions of the two magnetic core coils is stored in the ROM chip.

[0012] Furthermore, the material of the needle body housing is a low-magnetic metal material including austenitic stainless steel, titanium, or titanium alloy; the wall thickness is not greater than 0.2 mm, and the outer diameter is not greater than 1.4 mm.

[0013] Furthermore, the magnetic core of the magnetic core coil is made of a material with high magnetic permeability and low coercivity including amorphous wire material; the outer diameter of the coil is not greater than 0.5 mm, the diameter of the magnetic core is about 0.1, and the length is not greater than 5 mm.

[0014] Furthermore, the substrate inside the tubular housing is a flexible FPC or an ultra-thin PCB board, which is used to install the two magnetic core coils at the same position on both sides of the substrate, with a fixed installation included angle; and it provides pads for the connection of the leads of the two magnetic core coils and the internal leads of the probe, and the leads of the two magnetic core coils are led out to the handle through the internal leads of the probe.

[0015] Furthermore, the coil sleeve inside the tubular housing is a thin-walled polyimide sleeve. By wrapping around the outside of the magnetic core coil and the substrate, on the one hand, it is used to position the substrate and the magnetic core coil as a whole at the central position near the puncture positioning point inside the needle body housing, and on the other hand, it is used to strengthen the insulation between the magnetic core coil and the needle body housing; the inside of the coil sleeve and the inside of the housing adjacent to the sleeve use a filling glue including two-component epoxy resin for position fixing and maintaining rigidity.

[0016] Furthermore, inside the needle body housing, a probe inner lining made of a material including polyimide or polytetrafluoroethylene is also arranged from the filling glue position to the end of the needle body, which is used to protect the internal leads of the probe and provide insulation. Its inside is hollow to maintain the elasticity of the probe.

[0017] Furthermore, the installation position of the coil sleeve wrapping the coil and the substrate inside the needle body housing is slightly retracted relative to the opening at the top of the needle body housing, forming a small cavity at the position away from the opening at the top of the housing, so as to fill the glue to form a plug, or install a plug made of plastic or low-magnetic metal material, which is used to close the opening of the cannula needle housing and increase the robustness of the sensor.

[0018] Further, in the process of probe manufacturing, first, the positioning of two core coils on the substrate is completed, as well as the soldering of the coil leads and the internal leads of the probe; after all the internal parts of the probe are placed in place during probe encapsulation, epoxy resin is injected at one time to complete the encapsulation; or before inserting the outer shell capillary, epoxy resin is injected into the inner sleeve of the coil part, and after curing together with the internal substrate and coil to form a cylindrical probe, the probe is then encapsulated.

[0019] Further, the mapping process of the calibration data includes:

[0020] 1) Use a tooling to set a reference point, which is a relatively shallow circular concave pit for the tip of the probe of the probe-type sensor to be positioned therein;

[0021] 2) Connect the probe-type sensor to be mapped to the medical electromagnetic navigation device to make the medical electromagnetic navigation device work properly;

[0022] 3) Press the tip of the probe against the mapping reference point and use the medical electromagnetic navigation device to collect measurement data;

[0023] 4) According to the collected data, calculate the 5-axis degree-of-freedom pose measurement data of the two core coils respectively;

[0024] 5) According to the 5-degree-of-freedom pose measurement data of the two core coils, calculate the relative position, direction, and included angle of the two core coils, and use the midpoint of the position coordinates of the two core coils as the comprehensive position of the core coil for subsequent mapping calculations;

[0025] 6) Change the pose of the probe-type sensor and perform multiple measurements. Since the position of the puncture positioning point remains unchanged during each measurement, the spatial position of the puncture positioning point can be calculated, so as to obtain the relative installation position of the puncture positioning point and the two core coils, forming calibration data;

[0026] 7) Store the calibration data in the ROM chip; complete the mapping of the puncture positioning point data.

[0027] One of the beneficial effects that can be achieved by the present invention is as follows:

[0028] The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field disclosed by the present invention, as a high-sensitivity 6-degree-of-freedom probe-type sensor, improves the measurement sensitivity and signal-to-noise ratio under an alternating magnetic field, has good reliability, and is convenient for holding and operating.

[0029] The puncture positioning error can be less than 0.2 mm, which can effectively support the realization of high-precision puncture navigation. Description of the Drawings

[0030] The accompanying drawings are only for the purpose of showing specific embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference signs denote the same components.

[0031] Figure 1 Schematic connection diagram of the probe - type sensor in the embodiment of the present invention;

[0032] Figure 2 Schematic internal structure diagram of the probe part in the embodiment of the present invention;

[0033] Figure 3 Schematic structure diagram of the coil and substrate part in the embodiment of the present invention;

[0034] Figure 4 Schematic structure diagram of the plug - head at the end of the probe in the embodiment of the present invention;

[0035] Figure 5 Schematic diagram of the handle assembly in the embodiment of the present invention;

[0036] Figure 6 Schematic internal wiring diagram of the handle in the embodiment of the present invention.

[0037] Reference signs in the drawings: 1 - probe, 2 - handle, 3 - connecting cable, 4 - connector, 101 - probe housing, 102 - magneto - sensitive core coil, 103 - magneto - sensitive core coil, 104 - substrate, 105 - coil lead, 106 - coil lead, 107 - internal probe lead, 108 - internal probe lead, 109 - pad, 110 - pad, 111 - internal probe lead in the handle, 112 - internal probe lead in the handle, 113 - coil sleeve, 114 - encapsulating filler, 115 - probe lining, 116 - plug - head, 201 - upper housing, 202 - lower housing, 203 - adapter board, 204 - first set of adapter pads, 205 - second set of adapter pads, 206 - positioning groove, 207 - positioning post, 301 - cable lead. Detailed implementation manners

[0038] The preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings, in which the drawings form a part of this application and are used together with the embodiments of the present invention to explain the principles of the present invention.

[0039] An embodiment of the present invention discloses a probe - type sensor for puncture navigation in cooperation with an alternating magnetic field, as Figure 1 shown, which includes a probe, a handle, a connecting cable and a connector;

[0040] As Figure 2 shown, the probe includes: a needle body housing, a magneto - sensitive element, a substrate and a coil sleeve; wherein,

[0041] The end of the needle body shell is connected to the handle, and the top is the puncture positioning point. It adopts a thin-walled capillary structure and is made of a low-magnetic metal material.

[0042] The magnetosensitive element is two magnetically cored coils with the same parameters and a high aspect ratio, which are installed on the substrate at a fixed angle.

[0043] The coil sleeve is coated on the outside of the magnetically cored coil and the substrate, and is used to fixedly install the magnetically cored coil and the substrate together at the central position near the puncture positioning point inside the needle body shell.

[0044] The relative positions, directions, angles and installation positions of the two magnetically cored coils are stored in the sensor as calibration data for positioning calibration during puncture.

[0045] The handle is connected to the probe. One end of the connection cable passes through the inside of the handle and is connected to the coil leads of the two magnetically cored coils inside the probe, and the other end is connected to the connector.

[0046] The connector is a multi-pin connector, which is used to connect the probe-type sensor to the medical electromagnetic navigation device. A ROM chip is set inside the connector, and the calibration data including the relative positions, directions, angles and installation positions of the two magnetically cored coils is stored in the ROM chip.

[0047] The multi-pins include the pins connected to the connection cable, the pins connected to the ROM chip, and some reserved pins.

[0048] During puncture navigation, the probe-type sensor is connected to the medical electromagnetic navigation device. The operator places the tip of the probe at the puncture position, so that the probe-type sensor is within the working range of the magnetic field transmitter of the navigation device, and the two magnetically cored coils in the probe send the measurement signals obtained by inducing the magnetic field signals to the medical electromagnetic navigation device. The 5-degree-of-freedom spatial positions of the two magnetically cored coils with an installation angle are calculated. Combining the 5-degree-of-freedom (3 position coordinates, 1 azimuth angle and 1 pitch angle) spatial positions of the two magnetically cored coils and the calibration data of the probe, the 6-degree-of-freedom (3 position coordinates, 1 azimuth angle, 1 pitch angle and 1 roll angle) spatial position relative to the puncture positioning point is located, realizing high-precision puncture navigation. The specific method for calculating the spatial position is not within the protection scope of the present invention, and any calculation method that can calculate 1 6-degree-of-freedom spatial position from the 5-degree-of-freedom spatial positions of two existing angles can be used.

[0049] Specifically, the needle body shell included in the probe is a thin-walled capillary cylindrical tube structure, and the material is a low-magnetic metal material including austenitic stainless steel, titanium or titanium alloy, meeting the relevant standards of medical devices and not requiring additional coating. Such as 304, 316, 316L stainless steel.

[0050] The wall thickness of the needle body shell is determined according to the required strength; for example, when used for intracranial hematoma puncture, the wall thickness is generally not more than 0.2 mm; the outer diameter is not more than 1.4 mm, and the length is 28 mm.

[0051] Such as Figure 2 the internal structure of the probe part in

[0052] In the two high aspect ratio and parameter-identical magnetically core coils included inside the tubular shell, the magnetic core is made of a high magnetic permeability and low coercivity material including amorphous wire material; the outer diameter of the coil is determined by the sensitivity and the required outer diameter of the probe. Preferably, the outer diameter of the coil is not more than 0.5 mm, the diameter of the magnetic core is about 0.1, and the length is not more than 5 mm. Increasing the length of the coil has more turns and higher sensitivity, but it will increase the resistance and lead to an increase in thermal noise. In this embodiment, the magnetic core of the above size is used for winding the coil, which can keep the level of thermal noise low while meeting the sensitivity requirements. Figure 3 as shown.

[0053] The coil sleeve inside the tubular shell is a thin-walled polyimide sleeve. By covering the outside of the magnetically core coil and the substrate, on the one hand, it is used to position the substrate and the magnetically core coil as a whole at the central position near the puncture positioning point inside the needle body shell, and on the other hand, it is used to strengthen the insulation between the magnetically core coil and the needle body shell; the inside of the coil sleeve and the inside of the shell adjacent to the sleeve use a filling glue including two-component epoxy resin for position fixing and maintaining rigidity.

[0054] The fixation of the coil and the substrate through the coil sleeve and the internally filled glue prevents the relative position deformation of the two magnet-core coils caused by the elastic deformation of the needle body shell due to the complex structure of the puncture position during puncture navigation, resulting in positioning errors. Moreover, the two magnet-core coils are installed at the same position on both sides of the substrate, so the total length of the structure composed of the substrate and the two coils in the outer shell is the shortest, ensuring that the influence of deformation is minimized after being squeezed and guaranteeing the positioning accuracy. Of course, when the substrate is long enough, the two coils can also be arranged one after the other, but it may be affected by the deformation of the outer shell, and the reliability of the positioning accuracy is not as good as the arrangement method where the two magnet-core coils are installed at the same position on both sides of the substrate.

[0055] This embodiment also discloses a selection and configuration method for magnet-core coils. In this method, the two magnet-core coils adopt different parameter structures to provide different induction signals;

[0056] Among them, the first coil of the two magnet-core coils is used to provide the induction signals for measuring the 5-degree-of-freedom pose of the probe-type sensor except for the rolling angle; the second coil is used to provide the induction signal for measuring the rolling angle of the probe-type sensor; the first magnetic-sensitive element uses a longer coil and more turns relative to the second magnetic-sensitive element to obtain high sensitivity. The induction signals provided by the two magnet-core coils are measured separately to obtain 6-degree-of-freedom pose measurement data.

[0057] The installation method of the two magnet-core coils on the substrate is as follows: A rectangular first notch with a long side along the probe axis direction for accommodating the first coil is opened in the center of the substrate; the length and width of the first notch are slightly larger than those of the first coil, so that the first coil is positioned in the center of the substrate, the direction of the magnetic core is along the probe axis, and the coil is also in the middle position in the thickness direction of the substrate;

[0058] A rectangular second notch with a long side perpendicular to the probe axis direction for accommodating the second coil is opened in the center of the substrate behind the first notch; the length and width of the second notch are slightly larger than those of the second coil, so that the second coil is positioned on the probe axis and at a position perpendicular to the first coil.

[0059] The outer diameter of the first coil is slightly smaller than the inner diameter of the coil sleeve. When the inner diameter of the needle body shell is 1 mm, the outer diameter of the coil is not greater than 0.8 mm; the length of the magnetic core is 5 - 10 mm;

[0060] The length of the magnetic core of the second coil is slightly smaller than the inner diameter of the coil sleeve. In the case of a very small needle body shell, the second coil can use a non-magnetic-core coil to reduce the processing difficulty.

[0061] The first coil can be wound with enameled copper wire thicker than that of the second coil to obtain higher sensitivity and lower thermal noise; the second coil can use thinner enameled copper wire to get more turns in a smaller space.

[0062] The first coil and the second coil are bonded and positioned to the substrate using quick-drying glue or UV glue and fixed in their respective slots in the substrate. The first coil has a longer coil, more turns, and higher sensitivity. Due to the expandable longitudinal space, the first coil can also be made larger than the above-mentioned coil size according to the sensitivity requirements. Therefore, it is possible to improve the sensitivity of the induction signal for measuring the pose of 5 degrees of freedom except for the roll angle on the signal source and achieve higher positioning accuracy. However, due to the space limitation of the second coil, the sensitivity and positioning accuracy of the induction signal it can provide are less than those of the other 5 degrees of freedom when measuring the roll angle. This method is more suitable for application scenarios where the requirement for the measurement accuracy of the roll angle is lower than that of the other 5 degrees of freedom and can provide more sensitive and higher positioning accuracy for puncture navigation positioning.

[0063] Specifically, a probe inner lining is also provided inside the needle body housing; the position of the probe inner lining is from the end position where the glue filled with the magnetic core coil and the substrate is fixed to the end position of the needle body connected to the handle, which is used to protect the internal lead of the probe and for insulation. Its interior is hollow to maintain the elasticity of the probe; the material of the probe inner lining includes polyimide or polytetrafluoroethylene.

[0064] Specifically, as Figure 4 shown, the installation position of the coil sleeve covering the coil and the substrate inside the needle body housing is slightly retracted relative to the opening at the top of the needle body housing, forming a small cavity at a position away from the opening at the top of the housing to fill glue to form a plug, or install a plug made of plastic or low-magnetic metal material to close the opening of the cannula needle housing and increase the robustness of the sensor. Among them, the filled glue is a glue material corresponding to the medical standard including epoxy resin fixation or UV glue.

[0065] During the probe manufacturing process, first, the positioning of the two magnetic core coils on the substrate and the welding of the coil leads and the internal leads of the probe are completed; after all the internal parts are placed in place during the probe encapsulation, epoxy resin is injected at one time to complete the encapsulation; or before inserting the outer capillary of the housing, epoxy resin is injected into the inner sleeve of the coil part, and after curing together with the internal substrate and coil to form a cylindrical probe, the probe is then encapsulated to improve quality control.

[0066] As Figure 5 shown, the handle includes an upper housing, a lower housing, and an adapter plate placed in the cavity surrounded by the upper housing and the lower housing; a positioning slot for fixing the probe and a positioning hole for passing through the connection cable are provided on the lower housing;

[0067] AsFigure 6 As shown, a first set of transfer pads and a second set of transfer pads are provided on the adapter board; the first set of transfer pads and the second set of transfer pads each include 4 pads and are connected in one-to-one correspondence;

[0068] The 4 pads of the first set of transfer pads are respectively welded to two sets of twisted pairs of the internal leads of the probe led out to the handle; the 4 pads of the second set of transfer pads are respectively connected to 4 cables of the connection cable.

[0069] The probe is installed in the lower housing, positioned by the positioning groove, and a small amount of structural adhesive is applied to increase the fixing strength. The adapter board is positioned by the positioning posts. After welding and installation are completed, epoxy resin is injected into the lower housing, the upper housing is covered, and the handle is encapsulated after curing.

[0070] Each pair of twisted pairs in the connection cable is respectively connected to a coil through the adapter board. The cable has no shielding layer, and the outer diameter and material of the outer skin are selected according to the needs of specific applications. In addition, an aluminum foil or braided shielding layer can be added to the cable and grounded to improve the anti-interference ability. The twisted pairs can be enameled wires or conventional insulated wires, but cables that are not twisted internally and have no shielding should not be used. The cable length is usually not less than 2 meters and is determined according to actual needs.

[0071] The connector can be a commercial connector, made of plastic, determined in combination with the host interface of the medical electromagnetic navigation device, and is not limited to a specific model. There should be enough space inside the connector to install a ROM chip for storing the mapping parameters of the sensor and other information.

[0072] The number of internal pins of the connector is not less than 7. Among them, 4 are connected to the connection cable, at least 2 pins are connected to the data output pins of the ROM chip, and the other pins are spare pins.

[0073] In this embodiment, the mapping process of the calibration data of the probe-type sensor includes:

[0074] 1) Use a tooling to set a reference point, which is a relatively shallow circular pit for the tip of the probe of the probe-type sensor to be positioned therein;

[0075] 2) Connect the probe-type sensor to be mapped to the medical electromagnetic navigation device to make the medical electromagnetic navigation device work properly;

[0076] 3) Press the tip of the probe against the mapping reference point and use the medical electromagnetic navigation device to collect measurement data;

[0077] 4) According to the collected data, calculate the 5-axis degree-of-freedom pose measurement data of the two magnet-core coils respectively;

[0078] 5) Calculate the relative position, orientation, and included angle of the two core coils based on the 5-degree-of-freedom pose measurement data of the two core coils. Use the midpoint of the position coordinates of the two core coils as the comprehensive position of the core coil for subsequent mapping calculations;

[0079] 6) Change the attitude of the probe-type sensor and conduct multiple measurements. Since the position of the puncture positioning point remains unchanged during each measurement, the spatial position of the puncture positioning point can be calculated, thereby obtaining the relative installation position of the puncture positioning point and the two core coils to form calibration data;

[0080] 7) Store the calibration data in the ROM chip; complete the mapping of the puncture positioning point data.

[0081] In summary, the probe-type sensor for puncture navigation in cooperation with an alternating magnetic field in this embodiment, as a highly sensitive 6-degree-of-freedom probe-type sensor, improves the measurement sensitivity and signal-to-noise ratio under an alternating magnetic field, has good reliability, and is convenient for holding and operating. It can achieve a puncture positioning error of less than 0.2 mm and can effectively support the realization of high-precision puncture navigation.

[0082] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A probe - type sensor for puncture navigation in cooperation with an alternating magnetic field, comprising a probe, a handle, a connecting cable and a connector, characterized in that, The probe includes: a needle body housing, a magnetosensitive element, a substrate, and a coil sleeve; wherein, The end of the needle body housing is connected to the handle, and the top end is the puncture positioning point. It adopts a thin-walled capillary structure and is made of a low-magnetic metal material; The magnetosensitive element is two magnetically core coils with the same parameters, high aspect ratio, and installed on the substrate at a fixed angle; The coil sleeve is coated on the outside of the magnetically core coils and the substrate, and is used to fixedly install the magnetically core coils and the substrate together at the central position near the puncture positioning point inside the needle body housing; The relative positions, directions, angles, and installation positions of the two magnetically core coils are stored in the sensor as calibration data for positioning during puncture.

2. The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 1, wherein, A ROM chip is arranged inside the connector, and the calibration data including the relative positions, directions, angles, and installation positions of the two magnetically core coils is stored in the ROM chip.

3. The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 1, wherein, The material of the needle body housing is a low-magnetic metal material including austenitic stainless steel, titanium, or titanium alloy; the wall thickness is not greater than 0.2 mm, and the outer diameter is not greater than 1.4 mm.

4. The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 3, wherein, The magnetic core of the magnetically core coil adopts a high-permeability and low-coercivity material including amorphous wire material; the outer diameter of the coil is not greater than 0.5 mm, the diameter of the magnetic core is about 0.1, and the length is not greater than 5 mm.

5. The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 1, wherein, The substrate inside the tubular housing is a flexible FPC or an ultra-thin PCB board, which is used to install the two magnetically core coils at the same position on both sides of the substrate, with a fixed installation angle; and provides pads for the connection of the leads of the two magnetically core coils and the internal leads of the probe; the leads of the two magnetically core coils are led out to the handle through the internal leads of the probe.

6. The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 5, wherein, The coil sleeve inside the tubular housing is a thin-walled polyimide sleeve. By being coated on the outside of the magnetically core coils and the substrate, on the one hand, it is used to position the substrate and the magnetically core coils as a whole at the central position near the puncture positioning point inside the needle body housing, and on the other hand, it is used to strengthen the insulation between the magnetically core coils and the needle body housing; the inside of the coil sleeve and the inside of the housing adjacent to the sleeve adopt a filling glue including two-component epoxy resin for position fixing and maintaining rigidity.

7. The probe-type sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 6, wherein, Inside the needle body housing, a probe lining made of a material including polyimide or polytetrafluoroethylene is also provided from the filling glue position to the end of the needle body, which is used to protect the internal leads of the probe and provide insulation. Its inside is hollow to maintain the elasticity of the probe.

8. The probe sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 7, characterized in that: The installation position of the coil sleeve covering the coil and the substrate in the needle body shell is slightly retracted relative to the opening at the top of the needle body shell, forming a small cavity at a distance from the opening at the top of the shell, which is filled with glue to form a plug, or a plug made of plastic or low-magnetic metal material is installed to close the opening of the tube needle shell, thereby increasing the robustness of the sensor.

9. The probe sensor for puncture navigation in cooperation with an alternating magnetic field according to claim 8, characterized in that: During the probe manufacturing process, the two magnetic core coils are first positioned on the substrate, and the coil leads and the internal leads of the probe are welded; after the probe package has all the internal parts in place, epoxy resin is injected at one time to complete the package; or before the outer shell capillary is installed, epoxy resin is injected into the outer jacket of the coil part, and after it is cured together with the internal substrate and coil to form a cylindrical probe, the probe is packaged.

10. The probe sensor for puncture navigation in cooperation with an alternating magnetic field according to any one of claims 1 to 9, characterized in that: The calibration process of calibration data includes: 1) Use the tooling to set the reference point, which is a shallow circular pit in which the probe tip of the probe sensor is positioned; 2) Connect the probe sensor to be mapped to the medical electromagnetic navigation device to make the medical electromagnetic navigation device work normally; 3) Place the probe tip against the reference point and use the medical electromagnetic navigation equipment to collect measurement data; 4) Based on the collected data, the 5-axis DOF ​​position measurement data of the two magnetic core coils are calculated respectively; 5) According to the 5-DOF posture measurement data of the two magnetic core coils, the relative position, orientation and angle of the two magnetic core coils are calculated, and the midpoint of the position coordinates of the two magnetic core coils is used as the comprehensive position of the magnetic core coil for subsequent calibration calculation; 6) Change the posture of the probe sensor and perform multiple measurements. Since the position of the puncture positioning point remains unchanged during each measurement, the spatial position of the puncture positioning point can be calculated, thereby obtaining the relative installation position of the puncture positioning point and the two magnetic core coils to form calibration data; 7) The calibration data is stored in the ROM chip; the calibration of the puncture positioning point data is completed.

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