Medical puncture navigation system based on fixed reference frame and puncture needle

Abstract

The application discloses a medical puncture navigation system and a puncture needle based on a fixed reference system, which comprises a planning navigation module, a coordinate registration module, a puncture guide assembly and a posture monitoring and communication module. The puncture guide assembly is calibrated with the coordinate registration module before use to establish the corresponding relationship between the coordinate system of the puncture guide assembly and the fixed reference system, and the current space posture at the time of initialization is determined as the posture reference, so that the planning space angle parameter and the space posture angle data are in the same reference system. After the initialization calibration is completed, the real-time acquired space posture angle data and the planning space angle parameter are compared in the same reference system, and the guide information is output according to the comparison result to guide the puncture needle to implement the puncture needle insertion along the guide structure, and the needle insertion is controlled according to the puncture depth, so that a small-sized navigation system with low cost, high precision, simple operation and real-time feedback of the puncture angle is provided.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more particularly to a medical puncture navigation system and puncture needle based on a fixed reference frame. Background Technology

[0002] Puncture techniques are a crucial diagnostic and treatment method in modern medicine (such as tumor biopsy, radiofrequency ablation, and particle implantation). They involve inserting a needle with puncture function into human tissues or organs to collect samples, inject drugs or contrast agents, or perform treatments. It is a commonly used invasive examination or treatment method in clinical practice and is widely used for the diagnosis and adjuvant treatment of diseases in the brain, spinal cord, heart, lungs, and abdominal cavity. The key to this type of surgery is to accurately place the puncture needle into the lesion location, thus requiring a high level of spatial positioning ability, operational experience, and tactile sensitivity from the operator.

[0003] Currently, clinical practice mainly relies on the doctor's experience combined with imaging equipment such as ultrasound, CT, or DSA for manual puncture. While this method is widely used, it has significant drawbacks: 1) High operational threshold: Puncture accuracy highly depends on the doctor's personal experience, feel, and spatial positioning ability, lacking a standardized path guidance mechanism, resulting in a high operational threshold. 2) Risk of blind puncture: When relying solely on two-dimensional image guidance, doctors find it difficult to grasp the specific posture of the puncture needle in three-dimensional space in real time, especially unable to continuously judge the angular deviation between the current needle insertion direction and the predetermined puncture path, easily leading to repeated needle adjustments, thereby increasing patient pain and the risk of complications (such as pneumothorax, bleeding, etc.). 3) Radiation exposure: Under CT or DSA guidance, multiple scans are often required to confirm the puncture direction and needle tip position, resulting in unnecessary radiation exposure for both doctors and patients.

[0004] To address the aforementioned issues, existing technologies have proposed auxiliary solutions such as conventional angle locators, CT guides, and optical navigation-based robots. However, conventional angle locators and CT guides are cumbersome to manufacture, have low accuracy, and cannot flexibly adjust the guiding angle. They also cannot connect with the patient's 3D model or the predetermined puncture path, thus limiting their practical clinical significance. While optical navigation-based puncture surgery navigation devices can improve positioning accuracy to some extent, they generally suffer from high equipment prices, high maintenance costs, complex system layout and debugging, and low surgical efficiency.

[0005] Therefore, there is an urgent need for a navigation system that is low-cost, high-precision, easy to operate, and can provide real-time feedback on the puncture angle. Summary of the Invention

[0006] The technical objective of this invention is to provide a medical puncture navigation system based on a fixed reference frame. The system plans the puncture path based on medical images and compares the planned puncture angle with the real-time posture angle of the puncture guide component under a unified reference frame to guide the operator to complete a precise puncture. At the same time, it reduces the number of repeated scanning and calibration during the operation and improves the puncture success rate.

[0007] To solve the above problems, the technical solution of the present invention is as follows: This invention provides a medical puncture navigation system based on a fixed reference frame, characterized in that it includes: The planning and navigation module is used to acquire medical image data of the target object, plan the puncture path based on the lesion location and the puncture needle insertion point, and generate the planning spatial angle parameters and puncture depth of the puncture path in a fixed reference frame. The coordinate registration module is fixedly set at a predetermined position that has a defined spatial correspondence with the coordinate system of the imaging device, and is used to provide a spatial registration reference; The puncture guide assembly has a guide structure for defining the direction of needle insertion; An attitude monitoring and communication module, connected to the puncture guide component, is used to collect the spatial attitude angle data of the puncture guide component in real time and transmit it to the planning and navigation module. Before use, the puncture guide component is initialized and calibrated in conjunction with the coordinate registration module to establish the correspondence between the coordinate system of the puncture guide component and the fixed reference system, and to determine the current spatial attitude at the time of initialization as the attitude reference, so that the planned spatial angle parameters and the spatial attitude angle data are under the same reference system. The planning and navigation module is also used to compare the real-time acquired spatial attitude angle data with the planned spatial angle parameters in the same reference system after the initialization calibration is completed, and output guidance information according to the comparison result to guide the puncture needle to perform puncture and needle insertion along the guide structure, and control the needle insertion according to the puncture depth.

[0008] Preferably, the coordinate registration module includes: An initialization bracket is fixedly installed at a predetermined position that has a defined spatial correspondence with the fixed reference system, and its spatial pose remains constant after installation and positioning, so as to be used for repeated initialization calibration in multiple procedures; the initialization bracket is provided with a calibration positioning part; A positioning mating part is disposed on the puncture guide assembly and is used to connect with the calibration positioning part of the initialization bracket during initialization calibration to detachably fix and constrain the puncture guide assembly to a predetermined calibration position and keep it stationary, so as to establish the correspondence between the coordinate system of the puncture guide assembly and the fixed reference system.

[0009] Preferably, the planning and navigation module and the attitude monitoring and communication module are configured as follows: During initialization calibration, when in the reference frame binding state, the currently acquired initial attitude sensing data is obtained. The reference frame binding state is the state in which the puncture guide component establishes a definite spatial correspondence with the fixed reference frame via the initialization bracket. The current attitude of the puncture guide component is set as the attitude reference based on the initial attitude sensing data. The attitude reference is defined as a zero point, so that the current attitude angle is displayed as zero when the initialization calibration is completed, and the spatial attitude angle data displayed by the planning and navigation module after calibration is the relative angle change relative to the attitude reference.

[0010] Preferably, under the fixed reference system, an intersecting first reference projection plane and a second reference projection plane are set, and a preset reference axis is determined. The planned spatial angle parameters include a first planned angle and a second planned angle; the first planned angle is the angle between the projection of the puncture path in the first reference projection plane and the preset reference axis, and the second planned angle is the angle between the projection of the puncture path in the second reference projection plane and the preset reference axis; The spatial attitude angle data includes a first real-time angle and a second real-time angle; the first real-time angle is the angle between the projection of the current axis of the puncture guide component in the first reference projection plane and the preset reference axis, and the second real-time angle is the angle between the projection of the current axis of the puncture guide component in the second reference projection plane and the preset reference axis.

[0011] Preferably, the planning and navigation module is configured as follows: The planned puncture path is determined based on the three-dimensional spatial coordinates of the lesion location and the puncture needle insertion point under the fixed reference system, and the length of the planned puncture path is calculated as the puncture depth. Based on the angle relationship between the projections of the planned puncture path and the preset reference axis in the mutually perpendicular first and second reference projection planes, the first planned angle and the second planned angle are determined. During needle insertion, the needle displacement data along the guide structure is acquired, and the remaining needle insertion depth is determined based on the difference between the puncture depth and the needle displacement data, so as to generate depth navigation information characterizing the current needle insertion progress. The first planned angle, the second planned angle, the remaining needle insertion depth, and the angle deviation information obtained by comparing the spatial attitude angle data with the planned spatial angle parameters are fused and visualized. When the remaining needle insertion depth reaches a preset safety threshold or is zero, a warning message or a target point arrival prompt message is output.

[0012] Preferably, the planning and navigation module is further configured as follows: After the initial calibration is completed, the first real-time angle and the second real-time angle are acquired in real time, and the first angle deviation and the second angle deviation between them and the first planned angle and the second planned angle are calculated respectively. A two-dimensional dynamic view corresponding to the first and second reference projection planes is constructed on the display interface, and the planned projection baseline and real-time projection line are displayed respectively. In the two-dimensional dynamic view, tolerance display areas corresponding to preset angle guidance thresholds are set respectively. When the real-time projection lines are located within the corresponding tolerance display areas, angle matching prompt information is output. When any real-time projection line is located outside the corresponding tolerance display area, posture adjustment direction guidance prompt information is output. During the insertion of the puncture needle along the guide structure, the first angle deviation and the second angle deviation are continuously monitored. When either angle deviation exceeds the preset allowable deviation threshold for needle insertion, an angle deviation alarm message is output.

[0013] Preferably, the puncture guide assembly is a detachable puncture guide, which includes any one of a fixed-spacing puncture guide, an adjustable-spacing puncture guide, a multi-needle array guide, or a single-needle angle adjustable guide.

[0014] Preferably, the attitude monitoring and communication module includes an inertial measurement unit and a wireless communication unit; The inertial measurement unit is mounted on the puncture guide assembly and is used to collect the triaxial angular velocity and triaxial acceleration of the puncture guide assembly in real time, and to calculate and generate the spatial attitude angle data based on the triaxial angular velocity and triaxial acceleration. The wireless communication unit is used to transmit the spatial attitude angle data to the planning and navigation module in real time.

[0015] Preferably, the coordinate registration module establishes a definite spatial correspondence with the fixed reference system after one configuration. When performing initial calibration on different types of puncture guide components, the definite spatial correspondence is reused so that the replaced puncture guide component can still be included in the same fixed reference system after the initial calibration is completed, and compared with the planning spatial angle parameters output by the planning and navigation module.

[0016] The present invention also provides a puncture needle, comprising: The needle body is used to perform puncture and needle insertion, and the axis of the needle body constitutes a guide structure. The needle handle is connected to the needle body; An attitude monitoring and communication module, integrated on the needle handle, is used to collect the spatial attitude angle data of the puncture needle relative to a fixed reference system in real time, and send the spatial attitude angle data to an external planning and navigation module. A positioning and fitting part is provided on the puncture needle, which is used to detachably fit with the calibration and positioning part of the coordinate registration module before use, so that the puncture needle is fixed in the predetermined calibration position during initial calibration and the correspondence between the puncture needle's own coordinate system and the fixed reference system is established. After the initial calibration is completed, the puncture needle is detached from the coordinate registration module and, guided by the planned spatial angle parameters output by the planning and navigation module, is inserted through the needle axis.

[0017] Because the present invention adopts the above technical solution, it has the following advantages and positive effects compared with the prior art: This invention performs initial calibration with the puncture guide component through a coordinate registration module, ensuring that the posture angle of the puncture guide component and the image planning angle are expressed under the same fixed reference system, thereby establishing a stable mapping relationship between "image space - actual puncture space". The posture monitoring and communication module can collect the spatial posture changes of the puncture guide component in real time and feed them back to the planning and navigation module, facilitating adjustments by the operator against the planned angle and reducing the number of needle adjustments. It eliminates the need for complex optical tracking architectures, reflective ball arrays, or large robotic arms, resulting in a simple structure, low cost, and ease of promotion. Because the puncture direction can be continuously guided before and during needle insertion, the need for repeated CT or DSA scans to confirm the angle and needle tip position is reduced. This invention is applicable to different needles such as biopsy needles and puncture needles, and can be adapted to various guide configurations such as fixed-spacing puncture guides, adjustable-spacing puncture guides, multi-needle array guides, and single-needle angle adjustable guides. The coordinate registration module of this invention establishes a definite spatial correspondence with the imaging equipment coordinate system after a single configuration; subsequent procedures only require initial calibration to quickly complete the reference system binding, improving clinical efficiency. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention.

[0019] Figure 1 This is a block diagram illustrating the principle of a medical puncture navigation system based on a fixed reference frame in an embodiment of the present invention. Figure 2 This is a schematic diagram of the medical puncture navigation steps based on a fixed reference frame in an embodiment of the present invention; Figure 3 This is an example diagram of a puncture needle in an embodiment of the present invention. Detailed Implementation

[0020] The following specific examples illustrate the embodiments of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise stated, "a plurality of" means two or more.

[0021] It should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] This embodiment provides a medical puncture navigation system based on a fixed reference frame, which assists doctors in adjusting the puncture direction and controlling the needle insertion depth according to the medical image planning results during puncture diagnosis and treatment such as biopsy, ablation, particle implantation, and drug injection, so as to improve puncture accuracy, reduce the number of repeated needle adjustments, and reduce intraoperative image rescanning.

[0023] like Figure 1-2As shown, the medical puncture navigation system includes a planning and navigation module, a coordinate registration module, a puncture guidance component, and a posture monitoring and communication module. The planning and navigation module acquires medical image data of the target object, plans the puncture path based on the lesion location and the puncture needle insertion point, and generates the planned spatial angle parameters and puncture depth of the puncture path in a fixed reference frame. The medical image data can be from CT, CBCT, DSA, MRI, ultrasound, or other imaging devices capable of characterizing the lesion location and the puncture needle insertion point. In this embodiment, CT image data is preferred. The physician can select the lesion location and the puncture needle insertion point in the display and planning software corresponding to the planning and navigation module, and plan the puncture path based on these two parameters. Specifically, the planned spatial angle parameters can be used to characterize the spatial orientation of the puncture path relative to a preset reference direction in the fixed reference frame; the puncture depth can be determined by the spatial distance between the lesion location and the puncture needle insertion point. Preferably, the planning and navigation module can display the planned spatial angle parameters and puncture depth on the display interface in the form of numbers, graphics, projection lines, deviation prompts, or other visual methods for the operator's reference.

[0024] The coordinate registration module is fixedly installed at a predetermined position that has a defined spatial correspondence with the imaging equipment coordinate system, providing a spatial registration reference. This predetermined position can be a CT bed, imaging equipment gantry, operating table mounting location, or other positions that maintain a stable spatial pose relative to the imaging equipment coordinate system after installation. By fixing the coordinate registration module at the aforementioned predetermined position, a defined spatial correspondence can be established between it and the imaging equipment coordinate system after a single installation and configuration, thus providing a unified and reusable fixed reference reference for initial calibration in subsequent procedures.

[0025] The puncture guide assembly has a guide structure for defining the insertion direction of the puncture needle; the guide structure can be a needle guide groove, guide hole, guide tube, or other structure capable of defining the axial direction of the puncture needle. During actual puncture, the operator can insert the puncture needle along the guide structure, ensuring that the insertion direction of the puncture needle is aligned with the guide axis determined by the current posture of the puncture guide assembly. The puncture guide assembly can be a single-needle puncture guide device, a multi-needle puncture guide device, a fixed-spacing puncture guide, an adjustable-spacing puncture guide, a multi-needle array guide, a single-needle angle adjustable guide, or a micro-navigation puncture structure integrated with the puncture needle; this embodiment does not limit this.

[0026] The attitude monitoring and communication module is connected to the puncture guide component and is used to collect the spatial attitude angle data of the puncture guide component in real time and transmit it to the planning and navigation module. The attitude monitoring and communication module can be integrated inside the puncture guide component or installed on the handle, connecting part or bearing part of the puncture guide component.

[0027] Specifically, the attitude monitoring and communication module includes an inertial measurement unit (IMU), a communication unit, and a power management unit. The IMU is preferably an inertial measurement unit (IMU) integrating a three-axis gyroscope, a three-axis accelerometer, and a three-axis magnetometer. The gyroscope detects angular velocity information in real time, the accelerometer detects the gravitational acceleration component, and the magnetometer senses the geomagnetic direction. The system can integrate the three-axis angular velocities and fuse the data from the accelerometer and magnetometer to calculate the current attitude of the puncture guidance component in space in real time. The current attitude can be represented by pitch, yaw, and roll angles, or further converted into real-time angle parameters for comparison with planned spatial angle parameters. To reduce long-term drift errors caused by gyroscope integration, the attitude monitoring and communication module can incorporate complementary filtering, Kalman filtering, extended Kalman filtering, or other attitude fusion algorithms. These algorithms utilize low-frequency reference information provided by the accelerometer and magnetometer to dynamically correct the gyroscope integration results, thereby improving attitude stability and angle accuracy during long-term use. The communication unit can use low-power Bluetooth, 2.4G wireless protocol or other wired / wireless communication methods to send the drift-compensated spatial attitude angle data to the planning and navigation module in real time; the power management unit can use micro lithium battery, button battery, rechargeable micro power module or external power supply structure, and can be configured with standby, sleep, wake-up and low power alarm mechanisms to meet the miniaturization and low power consumption requirements of reusable instruments or disposable consumables.

[0028] In this embodiment, the puncture guide component undergoes initialization calibration in conjunction with the coordinate registration module before use to establish the correspondence between the puncture guide component's own coordinate system and the fixed reference system, and to determine the current spatial attitude at the time of initialization as the attitude reference, thereby ensuring that the planned spatial angle parameters and spatial attitude angle data are under the same reference system. Specifically, the operator can first physically connect the puncture guide component to the initialization bracket of the coordinate registration module through its positioning mating part, so that the puncture guide component is detachably fixed at the predetermined calibration position and kept stationary; then, the initialization calibration command is triggered on the software interface corresponding to the planning and navigation module. The planning and navigation module and the attitude monitoring and communication module are configured to: upon receiving the initialization calibration command, first determine whether the current state is a reference system binding state; the reference system binding state refers to the state in which the puncture guide component establishes a definite spatial correspondence with the fixed reference system through the initialization bracket, and the current attitude is physically constrained and kept stationary. This state can be comprehensively judged by whether the positioning and calibration positioning parts are reliably connected, and whether the angular velocity magnitude and acceleration fluctuation collected by the attitude monitoring and communication module are lower than preset thresholds. For example, within a continuous sampling window, when the angular velocity magnitude is less than a preset static threshold and the acceleration variance is less than a preset fluctuation threshold, it can be determined that the puncture guide component is in a static and reliably bound initialization state. In this state, the system reads the currently collected initial attitude sensing data. The initial attitude sensing data may include the raw output data of the gyroscope, accelerometer, and magnetometer, or the attitude angle data initially calculated based on the aforementioned raw data. Based on the initial attitude sensing data, the current attitude of the puncture guide component is set as the attitude reference. That is, after the puncture guide component completes the predetermined connection with the coordinate registration module, the current spatial orientation of the puncture guide component is defined as the reference initial state. In this state, the planning and navigation module and the attitude monitoring and communication module complete the reference system binding and attitude zeroing process, so that the current attitude angle when the initial calibration is completed is displayed as zero or a preset reference value. Therefore, the spatial attitude angle data subsequently acquired can be defined as the change in angle relative to the attitude reference, and can be uniformly compared with the planned spatial angle parameters generated under the same fixed reference system.

[0029] To address sensor installation errors and reference alignment issues, this embodiment employs a micro-navigation architecture, where the attitude monitoring and communication module is directly and physically integrated into the puncture guide assembly. Since the inertial measurement unit (IMU) chip moves synchronously with the needle, its sensed local coordinate system is the actual spatial coordinate system of the puncture guide assembly. This eliminates the multi-level transmission and calibration errors from "external base station - spatial mapping - surgical instruments" in traditional external navigation systems from a physical perspective. Because the sensor and the execution end are integrated (i.e., "needle-machine integration"), the system does not need to maintain a line-of-sight connection or electromagnetic field constraint between the external base station and the instrument during surgery. This makes the system not only compact and extremely low-cost, but also fundamentally eliminates the complex preoperative registration process of external optical or electromagnetic base stations, providing a technical basis for disposable consumables. The multi-level calibration mechanism introduced in this embodiment is based on the following principle: (1) Static gravity field calibration (six-sided method) and dynamic rotation calibration (ellipse fitting method): Since mechanical installation deviations are inevitable when the IMU chip is embedded in the needle handle, and the metal of the needle body will interfere with the geomagnetic field, the system uses the gravity vector as the absolute reference at the factory or before operation to collect accelerometer data of the needle in six orthogonal static states, calculate the zero bias and the scaling factor, eliminate mechanical deviations to ensure accurate tilt angle measurement; at the same time, the magnetometer data is collected through the figure-eight rotation motion, and the elliptical trajectory is fitted to eliminate metal interference and ensure accurate azimuth angle. (2) Intraoperative "zeroing" calibration: The IMU in the micro-navigation obtains the attitude based on the inertial space integration. If its absolute attitude data is used directly, it is not only complicated to solve but also easily affected by long-term drift, making it difficult to directly correspond to the planned path generated based on the CT image coordinate system. Therefore, this system designs an intraoperative zeroing calibration logic: the doctor places the intelligent puncture needle vertically. Since the direction of gravity is known and constant in the vertical state, the system sets the current attitude as the reference origin (attitude reference zero point) with one click through the software. Because this physical zero-point reference was established, all subsequent real-time IMU attitude outputs during the procedure were converted by the system into relative angle changes relative to this zero point. Simultaneously, the angle parameters for the planned path were calculated based on the needle insertion point and the lesion point under the same reference logic. In this way, the originally complex problem of absolute coordinate system registration was simplified to intuitive relative motion tracking, directly solving the technical challenge of the disconnect between the local coordinate system of the micro-navigation sensor and the global coordinate system of the medical image. This allows doctors to complete precise navigation solely based on the "relative deviation after zeroing," without needing to understand complex spatial transformations, greatly improving clinical usability.

[0030] In other words, this embodiment establishes a connection between the fixed reference system corresponding to the imaging equipment coordinate system and the actual spatial posture of the puncture guide component through the coordinate registration module, thereby realizing spatial mapping between the "image planning path" and the "realistic guide posture". Unlike the manual method that relies solely on the doctor's experience to determine the direction, this embodiment does not require the operator to directly complete the three-dimensional direction matching based on subjective spatial imagination. Instead, it first establishes a unified reference system through initial calibration, and then achieves dynamic comparison through real-time posture acquisition. After completing the initial calibration, the planning and navigation module also compares the real-time acquired spatial posture angle data with the planned spatial angle parameters under the same reference system, and outputs guidance information based on the comparison results to guide the puncture needle to perform puncture and insertion along the guide structure, and controls the needle insertion according to the puncture depth. The guidance information may include, but is not limited to: angle deviation value, adjustment direction prompts, two-dimensional projection view, posture matching prompts, out-of-tolerance alarms, and depth progress display, etc.

[0031] When the planning and navigation module determines that the spatial attitude angle data is consistent with the planned spatial angle parameters or is within the preset allowable deviation range, it indicates that the current guide axis of the puncture guide component is consistent with or parallel to the planned puncture path direction. At this time, the operator can insert the puncture needle along the guide structure and control the insertion distance according to the puncture depth so that the puncture needle gradually approaches and eventually reaches the lesion location.

[0032] Furthermore, in a preferred embodiment, the planning and navigation module not only outputs puncture direction guidance information, but also generates depth navigation information by combining the straight-line distance between the lesion location and the puncture needle insertion point. After adjusting the posture of the puncture guide component to meet the planning direction requirements, the operator can perform quantitative needle insertion based on the puncture depth displayed by the planning and navigation module. During the needle insertion process, the remaining needle insertion depth can be judged in real time by combining the needle body scale, displacement detection structure, or manually input needle insertion amount information, and a reminder message will be output when a preset safety threshold or target depth is reached to assist the operator in controlling the needle tip to reach the lesion location.

[0033] The medical puncture navigation system provided in this embodiment achieves a unified expression and dynamic correspondence between the puncture path planning result and the actual posture of the puncture guide component through a technical path of "image path planning - fixed reference system establishment - initialization calibration - real-time posture acquisition - angle comparison guidance - depth control needle insertion". Compared with traditional manual puncture, ordinary mechanical guides, or optical navigation devices that require complex arrangements, this embodiment has the advantages of simple structure, low cost, convenient operation, less affected by intraoperative obstruction, easy to repeat calibration, and suitable for clinical promotion.

[0034] In this embodiment, the coordinate registration module includes an initialization bracket, which is fixedly positioned at a predetermined location having a defined spatial correspondence with the fixed reference system. After installation and positioning, its spatial pose remains constant for repeated initialization calibration in multiple procedures. The predetermined location can be the edge of the CT scanner bed, the side of the bed board, an auxiliary fixing part of the operating table, or other structural positions that maintain a stable spatial position and orientation relative to the imaging equipment coordinate system after installation. The initialization bracket is provided with a calibration positioning part. The calibration positioning part can be a boss, slot, insertion hole, magnetic mating surface, limiting surface, or other mating structures capable of achieving repeated positioning and orientation constraint. Correspondingly, the puncture guide assembly is provided with a positioning mating part, which is used to connect with the calibration positioning part of the initialization bracket during initialization calibration to detachably fix and constrain the puncture guide assembly to a predetermined calibration position and keep it stationary, thereby providing a physical basis for establishing the correspondence between the coordinate system of the puncture guide assembly itself and the fixed reference system. Since the initialization bracket forms a definite spatial correspondence with the imaging equipment coordinate system once it is installed, the same fixed reference benchmark can be quickly reused in different procedures as long as the puncture guide component is repeatedly docked with the calibration positioning part through the positioning mating part, without having to re-establish a complex external spatial calibration relationship each time.

[0035] During initial calibration, the planning and navigation module and the attitude monitoring and communication module are configured to: when in a reference frame binding state, acquire the currently collected initial attitude sensing data. The reference frame binding state is the state in which the puncture guide component establishes a definite spatial correspondence with the fixed reference frame via the initialization bracket. The reference frame binding state can be understood as the puncture guide component being reliably connected to the initialization bracket, and the current attitude being physically constrained and remaining stationary. In this state, the attitude data output by the attitude monitoring and communication module is no longer simply derived from the drift coordinates of the device's own sensors, but rather forms a correspondence with the fixed reference datum provided by the coordinate registration module.

[0036] Based on the initial attitude sensing data, the current attitude of the puncture guide component is set as the attitude reference. This attitude reference is defined as a zero point, ensuring that the current attitude angle is displayed as zero upon completion of the initial calibration. Furthermore, the spatial attitude angle data displayed by the planning and navigation module after calibration represents the relative angle change relative to the attitude reference. In other words, after the initial calibration is completed, all subsequent displayed and calculated spatial attitude angle data are relative angle changes relative to the attitude reference. This allows the planning and navigation module to compare the planned spatial angle parameters obtained from medical image planning with the spatial attitude angle data collected in real-time by the attitude monitoring and communication module and processed after attitude zeroing, all within the same reference system. This avoids the incomparability of angles caused by inconsistencies between the image coordinate system and the sensor's local coordinate system.

[0037] Furthermore, in this embodiment, to represent the three-dimensional spatial orientation of the planned puncture path in a way that is more suitable for clinical operation understanding and guidance, intersecting first and second reference projection planes are set under the fixed reference system, and a preset reference axis is determined. Under the fixed reference system, with the CT equipment coordinate system as the reference, the head-to-foot direction is defined as the HF axis, the left-right direction as the LR axis, and the Z direction (i.e., the anterior-posterior direction of the human body, perpendicular to the CT scanning table surface) is defined, which is perpendicular to both the HF and LR axes. The first reference projection plane (HF-Z plane) is determined by the Z axis and the HF axis, and the second reference projection plane (LR-Z plane) is determined by the Z axis and the LR axis, with the Z axis as the preset reference axis. The two projection planes are perpendicular to each other. Based on this, the planned spatial angle parameters include a first planned angle and a second planned angle; the first planned angle is the angle between the projection of the puncture path onto the first reference projection plane and the preset reference axis, and the second planned angle is the angle between the projection of the puncture path onto the second reference projection plane and the preset reference axis; the spatial attitude angle data includes a first real-time angle and a second real-time angle; the first real-time angle is the angle between the projection of the current axis of the puncture guide component onto the first reference projection plane and the preset reference axis, and the second real-time angle is the angle between the projection of the current axis of the puncture guide component onto the second reference projection plane and the preset reference axis. Through the above dual-projection-plane angle definition method, the original puncture direction problem in three-dimensional space can be transformed into two independent but collaboratively reflective planar angle control problems, enabling the operator to more intuitively adjust the puncture direction based on the angles within the two projection planes.

[0038] In a preferred embodiment, the physician can select the lesion location 'a' and the puncture needle insertion point location 'b' on the display and planning software interface corresponding to the planning and navigation module. The system automatically reads the three-dimensional spatial coordinates of the two points in a fixed reference frame, denoted as the coordinates of point a (Xa, Ya, Za) and point b (Xb, Yb, Zb), respectively. The planning and navigation module determines the planned puncture path based on the three-dimensional spatial coordinates between the lesion location and the puncture needle insertion point location, and calculates the length of the planned puncture path as the puncture depth. The puncture depth L can preferably be obtained according to the three-dimensional spatial distance formula: Wherein, L represents the straight-line distance from the puncture point to the lesion location along the planned puncture path.

[0039] Furthermore, based on the angle relationship between the projections of the planned puncture path and the preset reference axis in the mutually perpendicular first and second reference projection planes, the first planning angle α and the second planning angle β are determined. For example, when the HF-Z plane and LR-Z plane are used as the two reference projection planes, and the Z-axis is used as the preset reference axis, the planning and navigation module can calculate the first planning angle α and the second planning angle β using trigonometric functions based on the coordinate difference between the lesion location and the puncture needle insertion point location. Specifically, the difference in the head-to-foot direction of the path vector in the fixed reference system can be set as ΔHF, the difference in the left-right direction as ΔLR, and the difference in the axial direction as ΔZ. Then, the first planning angle α and the second planning angle β can be calculated using atan2(ΔHF, ΔZ) and atan2(ΔLR, ΔZ) or other equivalent methods to ensure the correctness of the angle definition in different quadrants. The first planning angle α can characterize the degree of deflection of the puncture path relative to the Z-axis in the first reference projection plane, and the second planning angle β can characterize the degree of deflection of the puncture path relative to the Z-axis in the second reference projection plane. It should be noted that as long as the relationship between the planned path direction and the current direction of the guide structure can be represented under a unified reference system, the above angles can also be expressed in the form of Euler angles, direction vectors, direction cosines, quaternion transformation results or other equivalent parameters, and are not limited to the specific definition of the angle between the two projection planes.

[0040] After initial calibration, the attitude monitoring and communication module acquires the attitude change information of the puncture guide component in real time and continuously sends the spatial attitude angle data to the planning and navigation module. The inertial measurement unit in the attitude monitoring and communication module can collect three-axis angular velocity information, acceleration information, and geomagnetic direction information in real time. The system can calculate the current spatial attitude of the puncture guide component by integrating the three-axis angular velocity and combining it with accelerometer and magnetometer data for fusion correction. In a preferred implementation, the short-term attitude change can be obtained by gyroscope integration first, and then the long-term drift can be corrected by complementary filtering or Kalman filtering using accelerometer and magnetometer as reference quantities. Then, the attitude result calculated in the local coordinate system of the sensor can be converted to the fixed reference system to obtain the first real-time angle α′ and the second real-time angle β′. The communication unit can use a Bluetooth communication module, a low-power Bluetooth module, a 2.4G wireless transmission module, or other wired / wireless data transmission methods to send the first real-time angle α′ and the second real-time angle β′ to the planning and navigation module in real time at a preset refresh frequency, so that the planning and navigation module can continuously obtain the real-time angle information corresponding to the current posture of the puncture guide component.

[0041] After initial calibration, the navigation module acquires the first real-time angle and the second real-time angle in real time, and calculates the first angular deviation and the second angular deviation between them and the first and second planned angles, respectively. Specifically, if the first planned angle is α, the second planned angle is β, the first real-time angle is α′, and the second real-time angle is β′, then the first angular deviation Δα and the second angular deviation Δβ can be calculated. Here, α is the angle between the projection of the puncture path ab in the first reference projection plane (HF-Z plane) ab' and the Z-axis; β is the angle between the projection of the puncture path ab in the second reference projection plane (LR-Z plane) ab'' and the Z-axis; α′ is the angle between the projection of the current axis of the puncture guide component in the first reference projection plane and the Z-axis; β′ is the angle between the projection of the current axis of the puncture guide component in the second reference projection plane and the Z-axis. Δα is used to characterize the degree of deviation of the current guide axis from the planned path in the first reference projection plane, and Δβ is used to characterize the degree of deviation of the current guide axis from the planned path in the second reference projection plane. The deviation can be represented as a directional difference or as an absolute deviation value, depending on the interface guidance requirements. By monitoring the angular deviations within two mutually perpendicular reference projection planes, the system can transform the question of whether the guiding posture matches the planned puncture path into whether the deviations within the two planes fall within the allowable threshold range, without requiring the operator to perform complex three-dimensional spatial visualization. This significantly reduces the operational threshold.

[0042] In a preferred embodiment, the system calculates a first angular deviation Δα = α′ - α and a second angular deviation Δβ = β′ - β, and compares the first and second angular deviations with a preset static tolerance threshold. When both |Δα| and |Δβ| are less than or equal to the preset static tolerance threshold, it is determined that the current posture of the puncture guidance component matches the planned puncture path direction; when either |Δα| or |Δβ| is greater than the preset static tolerance threshold, it is determined that the current posture does not yet match the planned puncture path direction.

[0043] The display and planning module can further output corresponding posture guidance information based on the magnitude and direction of Δα and Δβ, such as prompting adjustments towards the head, feet, left, or right, or providing real-time feedback to the operator through directional indicator lines, deviation values, and color changes in the graphical interface. In this way, the doctor can hold the puncture guide component and gradually adjust its direction, so that the first real-time angle α′ and the second real-time angle β′ approach the first planned angle α and the second planned angle β, respectively.

[0044] When the first real-time angle α′ coincides with the first planned angle α, and the second real-time angle β′ coincides with the second planned angle β, the axial direction of the needle guide groove or needle guide hole on the puncture guide assembly is consistent with the spatial direction of the planned puncture path ab, and the two are parallel to each other. Subsequently, the doctor moves the puncture guide assembly to the patient's body surface, so that the puncture needle insertion point b is located on the axis of the guide groove or guide hole, and the guide axis forms a collinear relationship with the planned puncture path ab. At this time, puncture is performed along the direction of the guide axis, so that the actual puncture direction is consistent with the planned puncture path.

[0045] In one embodiment, the planning and navigation module can construct a two-dimensional dynamic view on the display interface corresponding to the first and second reference projection planes, and display the planning projection baseline and the real-time projection line respectively. The planning projection baseline indicates the direction of the planned puncture path within the corresponding projection plane, and the real-time projection line indicates the direction of the current axis of the puncture guide component within the corresponding projection plane. Further, tolerance display areas corresponding to preset angle guidance thresholds are set in the two-dimensional dynamic view. When the real-time projection lines are located within their respective tolerance display areas, angle matching prompts are output; when any real-time projection line is outside its corresponding tolerance display area, guidance prompts for attitude adjustment direction are output. Thus, tolerance display areas corresponding to preset angle guidance thresholds are set in the two-dimensional dynamic view, for example, a visible tolerance band with a certain angle range is formed on both sides of the planning projection baseline. When the real-time projection lines are located within their respective tolerance display areas, the planning and navigation module outputs angle matching prompts, such as color indicators, text prompts, graphic prompts, or voice prompts, to inform the operator that the current posture meets the needle insertion requirements. When any real-time projection line is outside its corresponding tolerance display area, the module outputs guidance prompts for posture adjustment, such as prompting the operator to adjust towards the head or foot in the first projection plane, or to the left or right in the second projection plane, so that the real-time projection lines gradually enter the corresponding tolerance areas. Thus, the operator can simultaneously complete angle adjustments in both projection planes under the guidance of the display interface until the current guide axis of the puncture guide component is consistent with the planned puncture path direction or reaches within the allowable error range. In an optional embodiment, the preset angle guidance threshold can also be adaptively adjusted according to the puncture depth, lesion size, lesion risk level, distribution of adjacent dangerous structures, or specific clinical scenarios. For example, a smaller allowable threshold can be used in superficial high-risk areas or areas adjacent to large blood vessels or nerve structures, while the allowable threshold can be appropriately relaxed in relatively low-risk scenarios, thereby achieving a balance between safety and operational convenience.

[0046] In addition to angle navigation, the planning navigation module can also provide needle insertion depth navigation. During needle insertion, the needle displacement data along the guide structure is acquired, and the remaining needle insertion depth is determined based on the difference between the puncture depth and the needle displacement data to generate depth navigation information characterizing the current needle insertion progress. The needle displacement data can be obtained in various ways, such as by manual input by the operator according to the needle body scale, or automatically acquired by a displacement sensor, encoder, sliding detection mechanism, or other displacement detection structure set on the guide assembly. Let the needle insertion displacement be L. in Then the remaining needle depth ΔL can be expressed as: ΔL = LL inWherein, L is the planned puncture depth calculated by the planning and navigation module based on the lesion location and the puncture needle insertion point location, and ΔL represents the remaining theoretical distance between the current needle tip and the target point. The planning and navigation module can also fuse and visualize the first planned angle, the second planned angle, the remaining needle insertion depth, and the angle deviation information obtained by comparing the spatial posture angle data with the planned spatial angle parameters, and output warning information or target point arrival prompt information when the remaining needle insertion depth reaches a preset safety threshold or is zero.

[0047] During the needle insertion along the guide structure, the first and second angle deviations are continuously monitored. When either angle deviation exceeds a preset allowable needle insertion deviation threshold, an angle deviation alarm is output. Specifically, the preset allowable needle insertion deviation threshold can be the same as the posture allowable threshold before needle insertion, or it can be set to a more stringent dynamic threshold to reduce the risk of path deviation caused by instrument force sway, patient respiratory movements, operator hand tremors, or changes in tissue resistance during needle insertion. In a preferred embodiment, the system can also be configured to ensure that the depth navigation prompt is in an effective advancement state only when the current angle deviation meets the preset range; if a significant angle deviation is detected, the current depth advancement prompt is frozen, weakened, or marked to prevent the operator from continuing to advance based on depth information when the direction is inaccurate, leading to target deviation. In clinical scenarios where respiratory movements are significantly affected, initial calibration, posture matching judgment, and key needle insertion steps can also be combined with the patient's breath-holding time, or, if necessary, initial calibration or intraoperative path update can be re-executed to further improve navigation accuracy.

[0048] To ensure that the puncture needle can advance along the planned puncture path during insertion and stop in time when it reaches the target point, the puncture guide component is synchronously aligned in two planes before insertion, based on the planned puncture path under a fixed reference system. During insertion, the angle deviation and remaining insertion depth are monitored in real time, and the direction priority, depth linkage and out-of-tolerance alarm control are realized through the status judgment logic.

[0049] After initial calibration is completed and the planned puncture depth L, first planned angle α, and second planned angle β are loaded, the following joint state determination steps are executed at each sampling time k: Step 1: Obtain the current first real-time angle αk′ and second real-time angle βk′ of the puncture guide component, and calculate the dual-plane angle deviation; when the dual-plane angle deviation is not greater than the preset static tolerance θ static When the needle insertion is detected, the output indicates that the needle can be inserted and the depth pedometer is unlocked; otherwise, the output indicates that the direction adjustment is enabled and the depth pedometer is kept at zero. Step 2: After detecting the needle insertion displacement, the current dual-plane angle deviation is calculated and compared with the dynamic tolerance θ. dyn Compare; when any angular deviation is greater than θdyn When the angle deviation is triggered, an angle deviation alarm is activated and a depth freeze mechanism is triggered to pause depth counting; when the angle deviation falls back into θ dyn Within the range, and continuously maintaining the state for a preset stable duration Δt. stable Then, release the deep freeze mechanism; Step 3: Based on the current needle displacement d k Calculate the remaining needle depth ΔL k When the ΔL k When the preset end-approach condition is met, the currently allowed angle alarm threshold is reduced to the preset end-approach threshold θ. end , where θ end Less than the θ dyn Step 4: Based on the current remaining needle depth ΔL k Based on the current dual-plane angular deviation, estimate the comprehensive prediction offset E. k When the E k Greater than or equal to the preset safe radius R of the lesion safe At that time, a combined circuit breaker operation is executed, simultaneously outputting an angle over-limit alarm and locking depth advancement. Estimate the comprehensive prediction offset E. k The steps include: calculating the end offset E within the first reference projection plane respectively. α,k =ΔL k ·tan|Δα k | and the end offset E within the second reference projection plane β,k =ΔL k ·tan|Δβ k |, where Δα k Δβ k The current biplane angular deviation; according to E α,k and E β,k Calculate the overall prediction offset E k E k The absolute linear offset distance of the needle tip relative to the planned endpoint in three-dimensional space is equal to the square root of the sum of the squares of the offset components of the first and second projection planes.

[0050] In this embodiment, the puncture guide component can adopt different structural forms to adapt to different clinical scenarios. In one implementation, the puncture guide component is a detachable puncture guide, such as any one of a fixed-spacing puncture guide, an adjustable-spacing puncture guide, a multi-needle array guide, or a single-needle angle adjustable guide, or it can be the puncture needle itself with integrated micro-navigation. The fixed-spacing puncture guide can be provided with multiple guide grooves or guide holes with constant spacing and parallel to each other, which is suitable for puncture operations with multiple parallel needle placement; the adjustable-spacing puncture guide can change the spacing between multiple guide structures through a mechanical adjustment mechanism to adapt to the ablation coverage requirements of lesions of different sizes; the multi-needle array guide can be provided with multiple guide holes arranged in a matrix on the plate to form a rectangular or other needle placement array; the single-needle angle adjustable guide can change the direction of the single-needle guide structure through an arc-shaped guide rail, a universal adjustment mechanism, or a swing structure to adapt to the requirements of flexible angle puncture in biopsy, single-needle ablation, etc.

[0051] In another embodiment, the puncture guidance component can also be a puncture needle with integrated micro-navigation. The attitude monitoring and communication module is embedded inside the puncture needle, and the needle body axis directly constitutes the guiding structure. The puncture needle is provided with a positioning mating part, which is used to cooperate with the coordinate registration module during initialization calibration to establish the correspondence between the puncture needle and the fixed reference system. The positioning mating part can be a calibration cap, positioning sleeve, docking part, snap-fit ​​part, plug-in part, or other structural forms that can achieve repeated positioning and attitude constraints, but is not limited to the specific forms mentioned above. After the initialization calibration is completed, the puncture needle is detached from the coordinate registration module, and its needle body itself acts as the guiding structure for puncture and subsequent treatment, thereby further reducing the system size, reducing instrument switching steps, and improving the integration of navigation and treatment.

[0052] Those skilled in the art will understand that the coordinate registration module establishes a defined spatial correspondence with the fixed reference system after a single configuration, and this defined spatial correspondence is reused when performing initial calibration on different types of the puncture guide components. In other words, although different guide components may differ in their structural form, number of guiding structures, and purpose, as long as a standard docking relationship can be established with the initialization support through the corresponding positioning mating part, and an initial calibration is completed, the replaced puncture guide component can be incorporated into the same fixed reference system and compared with the planned spatial angle parameters output by the planning and navigation module. This design eliminates the need for the system to re-establish the overall spatial system after replacing the guide component; it only requires a quick initialization and zeroing operation to restore the navigation state, thereby shortening preoperative preparation time and improving the device's versatility.

[0053] Therefore, this embodiment provides a unified and reusable spatial registration reference by fixing the coordinate registration module at a predetermined position that has a definite spatial correspondence with the coordinate system of the imaging device. The detachable positioning and engagement between the puncture guide component and the coordinate registration module allows the puncture guide component to be constrained to a predetermined calibration position during initialization. Real-time acquisition and communication of the guide component's spatial attitude via the attitude monitoring and communication module enables the planning and navigation module to dynamically compare the real-time attitude angle with the planned spatial angle parameters under a unified reference system. Combined with puncture depth calculation and remaining needle insertion depth indication, this achieves integrated puncture navigation from image planning, reference system one, angle guidance to depth control. Compared to traditional manual puncture methods that rely on physician experience, this embodiment significantly reduces the dependence on the operator's spatial imagination and tactile experience, minimizing repeated needle adjustments and multiple image rescans. Compared to ordinary mechanical locators, this embodiment can dynamically link image planning results with actual guiding posture and provide real-time angle feedback. Compared to high-cost systems based on optical navigation, this embodiment does not rely on infrared cameras, reflective markers on the body surface, or unobstructed vision conditions, is less affected by obstructions from personnel and instruments during surgery, and has a simpler system structure, lower cost, and easier deployment, making it more suitable for widespread application in routine clinical settings and primary healthcare institutions.

[0054] In one specific implementation, the steps from system power-on to puncture completion are as follows: First, the spatial relationship between the lesion point and the needle insertion point is obtained through CT images. Then, the planning and display module generates the planned path and its dual-plane angle and depth parameters. Subsequently, the fixedly installed coordinate registration module is used to initialize and calibrate the puncture guidance module, establishing a unified correspondence between its posture reference system and the CT equipment coordinate system. Next, the posture monitoring and communication module acquires the current angle data of the puncture guidance module in real time and compares it with the planned angle to guide the doctor to complete the alignment. Finally, the needle is inserted along the aligned puncture guidance axis, and the posture deviation and remaining depth are continuously monitored during the insertion process. Compared with traditional manual puncture relying on doctor experience, this embodiment transforms the originally difficult-to-quantify three-dimensional puncture posture problem into a visual, comparable, and adjustable dual-plane angle control problem by combining a fixed reference system, one-click initialization, and real-time angle display, thereby improving the standardization and clinical repeatability of the puncture operation. The specific steps are explained below: Step S1: Acquire patient images and determine the lesion and needle insertion point. Before the procedure, the doctor makes a preliminary judgment on possible puncture paths based on the patient's previous imaging data, lesion location, and surrounding anatomical structures, and can pre-mark one or more candidate needle insertion points on the patient's body surface. Subsequently, a CT scanner is used to scan the patient's target area to obtain CT image data containing the lesion target and the marked needle insertion points on the body surface.

[0055] In this step, the CT image displays the lesion location 'a' and the needle insertion point location 'b' on the body surface. The lesion location 'a' and the needle insertion point location 'b' each have corresponding three-dimensional spatial coordinate information, such as a(Xa, Ya, Za) and b(Xb, Yb, Zb). This coordinate information forms the basis for subsequent planning of the puncture path, calculation of the puncture depth, and determination of the puncture direction parameters. Through a single image acquisition, the spatial relationship between the lesion target point and the candidate needle insertion point in the CT equipment coordinate system is established, providing the initial data foundation for subsequent mapping of the image space to the actual operating space.

[0056] Step S2: Import image data and plan the puncture path. Import the image data obtained from the CT scan into the display and planning module. The display and planning module can be a computer, tablet computer, or other general display platform with planning and display software installed. The doctor selects the lesion location a and the puncture needle insertion point b in the graphical interface of the display and planning module. The software automatically generates a planned puncture path ab from the needle insertion point to the lesion target point based on the spatial relationship between the two points.

[0057] In this embodiment, the planning and display software calculates the straight-line distance L between the lesion location a and the needle insertion point b based on their three-dimensional coordinates. This straight-line distance L is used as the theoretical puncture depth. Simultaneously, an orthogonal dual-plane reference system is established based on the CT equipment coordinate system (e.g., defining the cephalopelvic direction as HF, the left-right direction as LR, and the vertical reference axis as the Z-axis). The path ab is projected onto the HF-Z plane and the LR-Z plane respectively, and trigonometric functions are used to calculate the first planning angle α and the second planning angle β. Thus, the abstract three-dimensional spatial path is reduced in dimension and decomposed into two independent planar angle parameters, facilitating intuitive clinical adjustment.

[0058] Step S3: Perform zero-point calibration of the puncture guide assembly using the coordinate registration module. The coordinate registration module (such as an initialization bracket) is fixedly set at a predetermined position with a constant pose relative to the coordinate system of the CT equipment, such as the CT table.

[0059] In this embodiment, the coordinate registration module includes a fixed reference part fixedly installed at a predetermined position on the CT equipment, CT scanning bed, bedside fixed structure, or operating room, and an initialization interface structure installed on the puncture guidance module. The fixed reference part is positioned relative to the coordinate system of the CT equipment and is installed or pre-calibrated before use, thereby constituting the fixed reference system carrier of the entire system.

[0060] The doctor physically connects the puncture guidance module to the coordinate registration module through its initialization interface structure, ensuring the puncture guidance module is in a stable and fixed state during initialization. At this time, the attitude monitoring and communication module is fixed along with the puncture guidance module, and its spatial attitude is consistent with the reference attitude of the coordinate registration module.

[0061] Subsequently, the doctor performs initialization operations in the software interface of the display and planning module, such as clicking the initialization function key. After the system detects that the puncture guidance module and the coordinate registration module have established a positioning connection, it reads the current posture monitoring data and defines the posture at that moment as the initialization reference posture. Through this initialization process, the initial errors generated by the puncture guidance module during assembly, transportation, installation, or static placement can be eliminated, ensuring that its subsequent output posture angle data maintains a unified reference relationship with the CT equipment coordinate system. The essence of this step is not to obtain the absolute posture of the puncture guidance module in natural space, but to establish a spatial mapping relationship between the image and reality by using an initialization reference structure with a fixed position relative to the CT equipment coordinate system, together with the posture monitoring coordinate system of the puncture guidance module and the image planning coordinate system.

[0062] After this step is completed, the real-time angle display value of the puncture guidance module in the display and planning module is reset to zero. The subsequent change in posture angle displayed by the system represents the deflection of the puncture guidance module relative to the initial reference posture. Establishing a unified reference system before the actual puncture ensures that the subsequently displayed real-time angle is comparable to the aforementioned planned angles α and β, thereby enabling the image planning results to be accurately mapped to the actual adjustment process of the clinical handheld instrument.

[0063] Step S4: Acquire and display the angle data of the puncture guidance module in real time. After initial calibration, the doctor removes the puncture guidance module from the coordinate registration module and moves it near the patient's body surface to prepare for puncture. The posture monitoring and communication module begins to continuously collect the current spatial posture data of the puncture guidance module and sends it to the display and planning module via Bluetooth communication module or other wireless / wired communication methods.

[0064] Step S5: Adjust the angle of the puncture guidance module to match the preset planned path. The doctor holds the puncture guidance module close to the patient's body surface and observes the real-time angle display results in the planning module. The doctor manually adjusts the spatial posture of the puncture guidance module so that its real-time angle gradually approaches the angle parameters corresponding to the planned path.

[0065] In this embodiment, the system does not simply compare whether α′ equals α and whether β′ equals β, but preferably adopts a dual-plane angle deviation judgment method. Specifically, the display and planning modules calculate the first angle deviation Δα = α′ - α and the second angle deviation Δβ = β′ - β, respectively, and compare them with a preset static tolerance threshold.

[0066] When both |Δα| and |Δβ| are less than or equal to the preset static tolerance threshold, the system determines that the current puncture guidance module attitude has matched the planned path direction. At this time, the real-time projection line in the display interface can be switched to the matching status display, and a prompt message will be output.

[0067] When either |Δα| or |Δβ| exceeds the static tolerance threshold, the system determines that the current posture is still not aligned and continues to output adjustment guidance information. For example, based on the positive and negative directions of Δα and Δβ, the system prompts the doctor to adjust the posture of the puncture guide module towards the head, foot, left, or right. Through this directional angular guidance method, the doctor can gradually achieve posture alignment consistent with the planned path without relying on subjective spatial imagination.

[0068] In this step, the system only allows the needle insertion stage when the angular deviations in both planar directions simultaneously meet the tolerance requirements. This is because the actual puncture path is a single direction in three-dimensional space. If only one direction's angle matches while the other still deviates, the actual needle path will not align with the planned path. By using real-time comparison of the angles in both planes under a fixed reference frame, the doctor can quickly adjust the puncture guidance module to a spatial direction consistent with the planned path, thereby reducing the difficulty of repeated trial and error and needle adjustment in traditional manual puncture.

[0069] Step S6: Insert the needle along the puncture guidance module and perform dynamic monitoring. When the system determines that the current posture of the puncture guidance module has matched the planned path, the doctor places the puncture needle into the needle guide groove or guide hole of the puncture guidance module and inserts the needle along the axis of the guide groove at the selected needle insertion point.

[0070] Since the attitude reference system of the puncture guidance module has been unified with the coordinate system of the CT equipment after initialization, and the direction of the guide groove axis of the puncture guidance module has been adjusted to be consistent with the planned path ab in step S5, when the puncture needle is advanced along the direction of the guide groove axis and the needle insertion point is located on the axis, the puncture needle can enter the body along the planned path and advance towards the lesion target.

[0071] In this embodiment, the system preferably continues to execute dynamic monitoring logic during needle insertion. On one hand, the posture monitoring and communication module continuously collects the posture changes of the puncture guidance module, and the display and planning module calculates the first angle deviation Δα and the second angle deviation Δβ in real time. When either deviation exceeds the preset dynamic threshold, the system immediately outputs an offset alarm, prompting the doctor to stop needle insertion and readjust the posture to avoid path deviation caused by factors such as tissue resistance, patient breathing, and operator hand micro-movements during needle insertion.

[0072] On the other hand, the system can also calculate the remaining needle insertion depth ΔL based on the planned puncture depth L and the current needle displacement, and output the corresponding depth prompts to the doctor. When the remaining depth enters the warning range, the system can indicate that the target point is about to be reached; when the planned depth is reached or exceeded, the system can indicate that the target point has been reached and stop needle insertion.

[0073] Therefore, the system described in this embodiment not only achieves path direction alignment before needle insertion, but also provides continuous guidance through posture monitoring and depth prompts during needle insertion, thereby improving puncture success rate and surgical safety.

[0074] In this embodiment, the initialization step is preferably performed once before each formal puncture operation. If, after initialization, the puncture guidance module is left unattended for a long time, reassembled, subjected to a collision, or may experience changes in attitude error due to other reasons, it is preferable to perform initialization calibration again to ensure that the subsequent attitude angle display maintains an accurate correspondence with the planned path parameters.

[0075] Based on the same inventive concept, this embodiment also provides a puncture needle, which serves as the core sensing end of the aforementioned medical puncture navigation system. This needle integrates attitude monitoring directly onto the needle, achieving "needle-machine integration," enabling real-time perception and guidance of spatial attitude without the need for an external base station. Figure 3 As shown, it specifically includes: Needle body 1 is used to perform puncture and needle insertion. The axis of needle body 1 forms a guide structure. The needle body is usually made of medical stainless steel and has a sharp tip to penetrate the skin and tissue. The surface of the needle body may be provided with depth scale so that the operator can read the insertion depth visually during the needle insertion process. Needle handle is connected to the needle body and is mainly used for doctors to hold and carry internal electronic components. The attitude monitoring and communication module 2, integrated on the needle handle, is used to collect the spatial attitude angle data of the puncture needle relative to a fixed reference frame in real time and send the spatial attitude angle data to an external planning and navigation module. Specifically, this module includes a cover plate, an integrated PCB board, and a housing. The integrated PCB board is equipped with a low-power six-axis or nine-axis IMU (integrating an accelerometer and gyroscope, with the nine-axis additionally including a magnetometer), a micro MCU, and a wireless communication module. The IMU acts as a "nerve ending" to collect spatial sensing data in real time; the micro MCU has a built-in Kalman filter or complementary filter algorithm to filter the raw data and send the attitude quaternion or Euler angle to an external terminal via Bluetooth Low Energy (BLE); to meet clinical aseptic requirements, the electronic components are encapsulated in the needle handle housing, and the outside is sealed with medical-grade polymer material. The entire system supports ethylene oxide sterilization, making the intelligent puncture needle meet the single-use standard and eliminating the need for complex postoperative disinfection and maintenance. A positioning mating part, disposed on the puncture needle, is used to detachably engage with the calibration positioning part of a coordinate registration module, such as an initialization bracket, before use. When the positioning mating part is connected to the coordinate registration module, the puncture needle is fixedly constrained to a predetermined calibration position (fixedly constrained to the predetermined calibration position and remains stationary). At this time, the system acquires the current attitude sensing data based on the gravity field and sets it as the attitude reference (zero point) with one click, establishing the correspondence between the puncture needle's own coordinate system and the fixed reference system. After the initial calibration is completed, the puncture needle is detached from the coordinate registration module and, guided by the planned spatial angle parameters output by the planning and navigation module, is inserted through the needle axis. Based on the above embodiments, to adapt to more complex surgical scenarios or different needs, this embodiment also provides the following implementation methods: the needle body may also be embedded with a fiber optic grating sensor to sense the bending deformation of the needle body caused by uneven tissue resistance during puncture; or a miniature pressure / temperature sensor may be added at the needle tip to assist in determining the needle tip position and achieve multimodal sensing fusion; in some scenarios sensitive to wireless signals, the needle handle can be directly connected to the host through a thin wire, using wired transmission to replace the wireless module; in addition to the terminal screen display, a display screen can be integrated on the needle handle to directly display the puncture angle, or a miniature laser emitter can be integrated to project the needle entry point onto the skin, or it can be used with AR glasses to project a virtual path into the doctor's field of vision, or provide tactile feedback through handle vibration; the electronic part containing the IMU can be made into a detachable and reusable handle to work with a disposable needle body; the needle body can also be designed as a multi-joint needle with flexible joints, and the IMU can be arranged in segments; in terms of application scenarios, it can be used in conjunction with ultrasound or MRI (using needles made of non-magnetic materials).

[0076] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they shall still fall within the protection scope of the present invention.

Claims

1. A medical puncture navigation system based on a fixed reference frame, characterized in that, include: The planning and navigation module is used to acquire medical image data of the target object, plan the puncture path based on the lesion location and the puncture needle insertion point, and generate the planning spatial angle parameters and puncture depth of the puncture path in a fixed reference frame. The coordinate registration module is fixedly set at a predetermined position that has a defined spatial correspondence with the coordinate system of the imaging device, and is used to provide a spatial registration reference; The puncture guide assembly has a guide structure for defining the direction of needle insertion; An attitude monitoring and communication module, connected to the puncture guide component, is used to collect the spatial attitude angle data of the puncture guide component in real time and transmit it to the planning and navigation module. Before use, the puncture guide component is initialized and calibrated in conjunction with the coordinate registration module to establish the correspondence between the coordinate system of the puncture guide component and the fixed reference system, and to determine the current spatial attitude at the time of initialization as the attitude reference, so that the planned spatial angle parameters and the spatial attitude angle data are under the same reference system. The planning and navigation module is also used to compare the real-time acquired spatial attitude angle data with the planned spatial angle parameters in the same reference system after the initialization calibration is completed, and output guidance information according to the comparison result to guide the puncture needle to perform puncture and needle insertion along the guide structure, and control the needle insertion according to the puncture depth.

2. The medical puncture navigation system based on a fixed reference frame as described in claim 1, characterized in that, The coordinate registration module includes: An initialization bracket is fixedly installed at a predetermined position that has a defined spatial correspondence with the fixed reference system, and its spatial pose remains constant after installation and positioning, so as to be used for repeated initialization calibration in multiple procedures; the initialization bracket is provided with a calibration positioning part; A positioning mating part is disposed on the puncture guide assembly and is used to connect with the calibration positioning part of the initialization bracket during initialization calibration to detachably fix and constrain the puncture guide assembly to a predetermined calibration position and keep it stationary, so as to establish the correspondence between the coordinate system of the puncture guide assembly and the fixed reference system.

3. The medical puncture navigation system based on a fixed reference frame as described in claim 2, characterized in that, The planning and navigation module and the attitude monitoring and communication module are configured as follows: During initialization calibration, when in the reference frame binding state, the currently acquired initial attitude sensing data is obtained. The reference frame binding state is the state in which the puncture guide component establishes a definite spatial correspondence with the fixed reference frame via the initialization bracket. The current attitude of the puncture guide component is set as the attitude reference based on the initial attitude sensing data. The attitude reference is defined as a zero point, so that the current attitude angle is displayed as zero when the initialization calibration is completed, and the spatial attitude angle data displayed by the planning and navigation module after calibration is the relative angle change relative to the attitude reference.

4. The medical puncture navigation system based on a fixed reference frame as described in claim 1, characterized in that, Under the fixed reference system, intersecting first and second reference projection planes are set, and a preset reference axis is determined; The planned spatial angle parameters include the first planned angle and the second planned angle; The first planning angle is the angle between the projection of the puncture path in the first reference projection plane and the preset reference axis; the second planning angle is the angle between the projection of the puncture path in the second reference projection plane and the preset reference axis. The spatial attitude angle data includes a first real-time angle and a second real-time angle; the first real-time angle is the angle between the projection of the current axis of the puncture guide component in the first reference projection plane and the preset reference axis, and the second real-time angle is the angle between the projection of the current axis of the puncture guide component in the second reference projection plane and the preset reference axis.

5. The medical puncture navigation system based on a fixed reference frame as described in claim 4, characterized in that, The planning and navigation module is configured as follows: The planned puncture path is determined based on the three-dimensional spatial coordinates of the lesion location and the puncture needle insertion point under the fixed reference system, and the length of the planned puncture path is calculated as the puncture depth. Based on the angle relationship between the projections of the planned puncture path and the preset reference axis in the mutually perpendicular first and second reference projection planes, the first planned angle and the second planned angle are determined. During needle insertion, the needle displacement data along the guide structure is acquired, and the remaining needle insertion depth is determined based on the difference between the puncture depth and the needle displacement data, so as to generate depth navigation information characterizing the current needle insertion progress. The first planned angle, the second planned angle, the remaining needle insertion depth, and the angle deviation information obtained by comparing the spatial attitude angle data with the planned spatial angle parameters are fused and visualized. When the remaining needle insertion depth reaches a preset safety threshold or is zero, a warning message or a target point indication message is output.

6. The medical puncture navigation system based on a fixed reference frame as described in claim 4, characterized in that, The planning and navigation module is also configured to: After the initial calibration is completed, the first real-time angle and the second real-time angle are acquired in real time, and the first angle deviation and the second angle deviation between them and the first planned angle and the second planned angle are calculated respectively. A two-dimensional dynamic view corresponding to the first and second reference projection planes is constructed on the display interface, and the planned projection baseline and real-time projection line are displayed respectively. In the two-dimensional dynamic view, tolerance display areas corresponding to preset angle guidance thresholds are set respectively. When the real-time projection lines are respectively within the corresponding tolerance display areas, angle matching prompt information is output. When any real-time projection line is outside the corresponding tolerance display area, posture adjustment direction guidance prompt information is output. During the insertion of the puncture needle along the guide structure, the first angle deviation and the second angle deviation are continuously monitored. When either angle deviation exceeds the preset allowable deviation threshold for needle insertion, an angle deviation alarm message is output.

7. The medical puncture navigation system based on a fixed reference frame as described in claim 1, characterized in that, The puncture guide assembly is a detachable puncture guide, which includes any one of a fixed-spacing puncture guide, an adjustable-spacing puncture guide, a multi-needle array guide, or a single-needle angle adjustable guide.

8. The medical puncture navigation system based on a fixed reference frame as described in claim 1, characterized in that, The attitude monitoring and communication module includes an inertial measurement unit and a wireless communication unit; The inertial measurement unit is mounted on the puncture guide assembly and is used to collect the triaxial angular velocity and triaxial acceleration of the puncture guide assembly in real time, and to calculate and generate the spatial attitude angle data based on the triaxial angular velocity and triaxial acceleration. The wireless communication unit is used to transmit the spatial attitude angle data to the planning and navigation module in real time.

9. The medical puncture navigation system based on a fixed reference frame as described in claim 2 or 7, characterized in that, After initial configuration, the coordinate registration module establishes a definite spatial correspondence with the fixed reference system. When performing initial calibration on different types of puncture guide components, the definite spatial correspondence is reused so that the replaced puncture guide component can still be included in the same fixed reference system after the initial calibration is completed, and is compared with the planning spatial angle parameters output by the planning and navigation module.

10. A puncture needle, characterized in that, include: The needle body is used to perform puncture and needle insertion, and the axis of the needle body constitutes a guide structure. The needle handle is connected to the needle body; An attitude monitoring and communication module, integrated on the needle handle, is used to collect the spatial attitude angle data of the puncture needle relative to a fixed reference system in real time, and send the spatial attitude angle data to an external planning and navigation module. A positioning and fitting part is provided on the puncture needle, which is used to detachably fit with the calibration and positioning part of the coordinate registration module before use, so that the puncture needle is fixed in the predetermined calibration position during initial calibration and the correspondence between the puncture needle's own coordinate system and the fixed reference system is established. After the initial calibration is completed, the puncture needle is detached from the coordinate registration module and, guided by the planned spatial angle parameters output by the planning and navigation module, is inserted through the needle axis.

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