Method and navigation system for navigating two intracranial operating instruments

Abstract

The invention discloses a method for navigating two intracranial operating instruments and a navigation system. The method comprises the following steps: acquiring an anatomical image; marking an operation path in the anatomical image; registering the anatomical image in the optical coordinate system based on the pose of the first optical tracker in the optical coordinate system and the pose of the first optical tracker in the image coordinate system of the anatomical image acquired by the optical navigation device; acquiring the pose of the second optical tracker in the optical coordinate system by using optical navigation equipment; obtaining the pose of the first electromagnetic sensor in the optical coordinate system based on the pose of the third optical tracker in the optical coordinate system, the pose relationship between the magnetic field generator and the third optical tracker, and the pose of the first electromagnetic sensor relative to the magnetic field generator obtained by using the optical navigation equipment; calibrating the pose of the first electromagnetic sensor; and obtaining the pose of the first instrument in the optical coordinate system and the calibrated pose of the second instrument in the optical coordinate system.

Description

Technical Field

[0001] The present invention relates to the technical field of surgical navigation, and in particular to a method and system for navigating two intracranial operating instruments in neurosurgery. Background Art

[0002] At present, there are two typical navigation systems for surgical navigation: optical navigation systems based on optical positioning and tracking principles and electromagnetic navigation systems based on electromagnetic positioning and tracking principles. Both navigation systems have their own advantages and disadvantages. Specifically, the advantage of the optical navigation system is that it can accurately locate and track medical operating instruments. Its disadvantage is that if the optical connection between the optical tracker attached to the medical operating instrument and the shooting device in the optical navigation device is blocked, the operating instrument cannot be located and tracked. The electromagnetic navigation system locates and tracks the operating instrument based on the current changes induced by the electromagnetic coil in the magnetic field generated by the magnetic field generator. Therefore, the advantage of the electromagnetic navigation system is that it is not affected by optical blockage and can be used for navigation in small operating spaces and closed lumens. The disadvantage of the electromagnetic navigation system is that the positioning and tracking are not as accurate as those of the optical navigation system, especially when the magnetic field is deformed by surrounding equipment, the positioning and tracking accuracy is even worse.

[0003] The application of navigation systems in neurosurgery (such as intracranial surgery) can realize the visualization of operating instruments during the operation. Since neurosurgery requires doctors to operate the operating instruments with high precision, optical navigation systems are usually used to locate and track the operating instruments. The favorable condition for using optical navigation systems to assist in neurosurgery is that the operating instruments are usually rigid instruments and the outer end (or proximal end) of the instruments is located outside the body. Therefore, the optical tracker can be installed on the outer end of the operating instrument to avoid being blocked by human tissue. In addition, in some types of operations (such as tumor biopsy), if only one operating instrument is needed, based on the doctor's skilled operation, the probability of the optical tracker being blocked by external objects can be significantly reduced.

[0004] In more types of neurosurgery, it is inevitable to use two operating instruments (for example, in the operation of removing glioma, two operating instruments are usually used at the same time), that is, two operating instruments are inserted into the skull incision, and the two operating instruments usually have different functions during the operation. For example, a neuroendoscope and a cutter (such as a phacoemulsification suction knife) are inserted into the skull incision at the same time, and the neuroendoscope is used to provide intracranial vision, and the cutter is used to remove the tumor. In the prior art, when both operating instruments are positioned and tracked using an optical navigation system, the following problems exist: To achieve positioning and tracking, two optical trackers are respectively attached to the outer ends of the two operating instruments (i.e., the proximal handheld ends). During the operation, the optical trackers on the two operating instruments occupy a large space and are prone to mutual interference or mutual shielding of optical markers (reflective components used to reflect light to the shooting equipment for positioning and tracking). The mutual interference will affect the allowed range of motion of the operating instruments, and shielding of light markers will cause interruption of the positioning and tracking of the operating instruments. Summary of the invention

[0005] In view of the above technical problems existing in the prior art, an embodiment of the present invention provides a method and a navigation system for navigating two intracranial operating instruments.

[0006] In order to solve the above technical problems, the technical solution adopted in the embodiments of the present invention is: A method for navigating two intracranial operating instruments, the two operating instruments comprising a first instrument and a second instrument, characterized in that a first optical tracker is attached to a surgical site, a second optical tracker and a first electromagnetic sensor are attached to the first instrument and the second instrument respectively in a determined posture relationship, and a third optical tracker has a determined posture relationship with a magnetic field generator, the method comprising: obtaining anatomical images depicting the anatomy of the surgical site; Marking the target area, cranial entrance, and surgical path in the anatomical image; Acquire the position and posture of the first optical tracker in the optical coordinate system by using an optical navigation device, and register the anatomical image in the optical coordinate system based on the position and posture of the first optical tracker in the optical coordinate system and the position and posture of the anatomical image in the image coordinate system; The optical navigation device is used to obtain the positions and postures of the second and third optical trackers in the optical coordinate system, and the electromagnetic navigation device is used to obtain the position and posture of the first electromagnetic sensor relative to the magnetic field generator. The position and posture of the first electromagnetic sensor in the optical coordinate system is obtained based on the position and posture of the third optical tracker in the optical coordinate system, the position and posture relationship between the magnetic field generator and the third optical tracker, and the position and posture of the first electromagnetic sensor relative to the magnetic field generator. Calibrate the position and posture of the first electromagnetic sensor; Based on the posture relationship between the second optical tracker and the first instrument and the posture relationship between the first electromagnetic sensor and the second instrument, the posture of the first instrument in the optical coordinate system and the calibrated posture of the second instrument in the optical coordinate system are obtained, and the first instrument and the second instrument are visualized in the anatomical image.

[0007] Preferably, the first instrument and the second instrument can be attached in a rigid and detachable manner, and in the attached state, the first instrument and the second instrument have a determined posture relationship; The calibrating the position and posture of the first electromagnetic sensor includes: Obtaining a position and posture of the first electromagnetic sensor relative to the second optical tracker based on a position and posture relationship between the first device and the second device in an attached state; The position of the first electromagnetic sensor in the optical coordinate system obtained based on the position of the first electromagnetic sensor relative to the second optical tracker in the attached state and the position of the second optical tracker in the optical coordinate system acquired by the optical navigation device is used as a reference position; The pose of the first electromagnetic sensor in the optical coordinate system obtained based on the pose of the third optical tracker in the attached state obtained by the optical navigation device, the pose relationship between the magnetic field generator and the third optical tracker, and the pose of the first electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device is used as the pose to be calibrated; A calibration matrix is ​​obtained based on the to-be-calibrated posture and the reference posture of the first electromagnetic sensor, and the posture of the first electromagnetic sensor in the optical coordinate system is calibrated using the calibration matrix.

[0008] Preferably, the second electromagnetic sensor is arranged at the surgical site or in the vicinity of the surgical site; The calibrating the position and posture of the first electromagnetic sensor includes: Using the position and posture of the second electromagnetic sensor in the optical coordinate system obtained based on the position and posture of the first optical tracker or the second optical tracker in the optical coordinate system as a reference position and posture of the second electromagnetic sensor; The position and posture of the second electromagnetic sensor in the optical coordinate system obtained based on the position and posture of the magnetic field generator in the optical coordinate system and the position and posture of the second electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device is used as the position and posture to be calibrated of the second electromagnetic sensor; The posture of the first electromagnetic sensor in the optical coordinate system obtained based on the posture of the magnetic field generator in the optical coordinate system and the posture of the first electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device is used as the posture to be calibrated of the first electromagnetic sensor; A calibration matrix is ​​obtained based on the to-be-calibrated posture of the second electromagnetic sensor and the reference posture, and the to-be-calibrated posture of the first electromagnetic sensor is calibrated using the calibration matrix.

[0009] Preferably, the second electromagnetic sensor is attached to the distal region of the first instrument in a manner to form a determined posture relationship with the second optical tracker, and the first electromagnetic sensor is attached to the distal region of the second instrument; Obtaining the reference position and posture of the second electromagnetic sensor in the optical coordinate system based on the position and posture of the second optical tracker in the optical coordinate system includes: The reference position and posture of the second electromagnetic sensor in the optical coordinate system is obtained based on the position and posture of the second optical tracker in the optical coordinate system acquired by the optical navigation device and the position and posture relationship between the second electromagnetic sensor and the second optical tracker.

[0010] Preferably, the second electromagnetic sensor has a determined posture relationship with the first optical tracker; Obtaining a reference position and posture of the second electromagnetic sensor in the optical coordinate system based on the position and posture of the first optical tracker in the optical coordinate system includes: The reference position and posture of the second electromagnetic sensor in the optical coordinate system is obtained based on the position and posture of the first optical tracker in the optical coordinate system acquired by the optical navigation device and the position and posture relationship between the second electromagnetic sensor and the first optical tracker.

[0011] The present invention also discloses a navigation system, which is used for performing surgical navigation on two intracranial operating instruments, the two operating instruments include a first instrument and a second instrument, and the navigation system includes an image acquisition device, a navigation instrument and a computer device; The navigation apparatus includes an optical navigation device, first, second and third optical trackers, an electromagnetic navigation device and a first electromagnetic sensor; Computer equipment includes processing control equipment and display equipment; The first optical tracker is attached to the surgical site, the second optical tracker and the first electromagnetic sensor are attached to the first and second instruments respectively in a determined posture relationship, and the third optical tracker is attached to the periphery of the surgical site and has a determined posture relationship with the magnetic field generator; The image acquisition device is used to acquire original images describing the anatomical structure of the surgical site; The optical navigation device is used to obtain the positions and postures of the first, second and third optical trackers in the optical coordinate system; The electromagnetic navigation device is used to obtain the position and posture of the first electromagnetic sensor relative to the magnetic field generator; Process control equipment is used to: Processing the image to be processed into an anatomical image; registering the anatomical image in the optical coordinate system based on the pose of the first optical tracker in the optical coordinate system and the pose of the first optical tracker in the image coordinate system of the anatomical image; Calculating the position and posture of the first device in the optical coordinate system based on the position and posture of the second optical tracker in the optical coordinate system and its position and posture relationship with the first device; and calculating the position and posture of the second device in the optical coordinate system based on the position and posture of the third optical tracker in the optical coordinate system, the position and posture relationship between the magnetic field generator and the third optical tracker, the position and posture of the first electromagnetic sensor relative to the magnetic field generator, and the position and posture relationship with the second device; Calibrate the position and posture of the first electromagnetic sensor; The display device is used to visualize the first and second instruments in the anatomical image.

[0012] Preferably, the first device has a first positioning structure, the second device has a second positioning structure, the first device and the second device can be detachably attached via the first positioning structure and the second positioning structure, and, in the attached state, the first device and the second device have a certain posture relationship; The processing control device is used to: The posture of the first electromagnetic sensor relative to the second optical tracker is calculated based on the posture relationship between the first device and the second device in the attached state; the posture of the first electromagnetic sensor in the optical coordinate system is calculated based on the posture of the first electromagnetic sensor relative to the second optical tracker in the attached state and the posture of the second optical tracker in the optical coordinate system and used as the reference posture; the posture of the first electromagnetic sensor in the optical coordinate system is calculated based on the posture of the third optical tracker in the attached state, the posture relationship between the magnetic field generator and the third optical tracker, and the posture of the first electromagnetic sensor relative to the magnetic field generator and used as the posture to be calibrated; the calibration matrix is ​​calculated based on the posture to be calibrated of the first electromagnetic sensor and the reference posture, and the calibration matrix is ​​used to calibrate the posture of the first electromagnetic sensor in the optical coordinate system.

[0013] Preferably, The navigation device further includes a second electromagnetic sensor, which is arranged at the surgical site or in the vicinity of the surgical site; The processing control device is used to: Based on the pose of the first optical tracker or the second optical tracker in the optical coordinate system obtained by the optical navigation device, the pose of the second electromagnetic sensor in the optical coordinate system is calculated and used as the reference pose; based on the pose of the magnetic field generator in the optical coordinate system and the pose of the second electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device, the pose of the second electromagnetic sensor in the optical coordinate system is calculated and used as the pose to be calibrated; based on the pose of the magnetic field generator in the optical coordinate system and the pose of the first electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device, the pose of the first electromagnetic sensor in the optical coordinate system is calculated and used as the pose to be calibrated; based on the pose to be calibrated of the second electromagnetic sensor and the reference pose, a calibration matrix is ​​calculated, and the pose to be calibrated of the first electromagnetic sensor is calibrated using the calibration matrix.

[0014] Preferably, The first electromagnetic sensor is arranged in a distal region of the second instrument and the second electromagnetic sensor is arranged in a distal region of the first instrument.

[0015] Preferably, the first electromagnetic sensor is arranged in the proximal region of the second instrument and the second electromagnetic sensor is arranged on the first optical tracker.

[0016] Compared with the prior art, the method and navigation system for navigating two intracranial operating instruments provided by the embodiments of the present invention have the following beneficial effects: 1. A first device and a second device are navigated simultaneously by operating an electromagnetic navigation device and an optical navigation device simultaneously, and navigation of the second device is achieved by the optical navigation device and the electromagnetic navigation device cooperating to obtain the position and posture of the first electromagnetic sensor in the optical coordinate system, thereby avoiding navigation of the second device by configuring an optical tracker on the second device. As there is no need to configure an optical tracker on the second device, the probability of the second optical tracker on the first device being shielded by the second device and the probability of mutual mechanical interference are significantly reduced, thereby reducing the probability of interruption of navigation of the operating device due to shielding and significantly increasing the range of movement of the two operating devices.

[0017] 2. The second instrument which may cause less potential damage to intracranial tissue due to posture deviation is navigated by the optical navigation device and the electromagnetic navigation device in coordination, while the first instrument which may cause greater potential damage to intracranial tissue due to posture deviation is navigated only by the optical navigation device, thereby reducing the impact of navigation deviation in electromagnetic navigation on surgical risks and effects.

[0018] 3. By calibrating the position deviation of the second device caused by electromagnetic navigation, the position deviation of the second device can be corrected to a certain extent, thereby improving the navigation accuracy of the second device to a certain extent.

[0019] 4. Other advantages of the present invention are directly or implicitly recorded in the specific implementation manner of the specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the configuration relationship of the relevant components of the navigation system provided by the present invention.

[0021] Figure 2 The present invention is a flowchart of the navigation method provided by the present invention.

[0022] Figure 3 This is a flow chart of specific implementation steps of step S10 in the navigation method provided by the present invention.

[0023] Figure 4 This is a flow chart of specific implementation steps of step S20 in the navigation method provided by the present invention.

[0024] Figure 5 An anatomical image with a first access path marked thereon provided by the present invention.

[0025] Figure 6 The anatomical image with the second access path marked is provided by the present invention.

[0026] Figure 7 A schematic diagram of the process of obtaining the posture of related instruments and equipment in the form of a transformation matrix provided by the present invention.

[0027] Figure 8 This is a flow chart of a first method for calibrating the position and posture of a first electromagnetic sensor provided by the present invention.

[0028] Fig. 9 The diagram is a schematic diagram of a calibration process of a first method for calibrating the position and posture of a first electromagnetic sensor in the form of a transformation matrix.

[0029] Fig.10 This is a flow chart of a second method for calibrating the position and posture of a first electromagnetic sensor provided by the present invention.

[0030] Fig.11 The diagram is a schematic diagram of a calibration process of a second method for calibrating the position and posture of a first electromagnetic sensor in the form of a transformation matrix.

[0031] Reference numerals: 10-optical navigation device; 101-camera; 11-first optical tracker; 12-second optical tracker; 13-third optical tracker; 20-electromagnetic navigation device; 21-first electromagnetic sensor; 22-second electromagnetic sensor; 221-mini pan-tilt head; 23-magnetic field generator; 31-first instrument; 32-second instrument; 40-computer equipment; 41-display equipment; 42-processing and control equipment; 50-operating bed. DETAILED DESCRIPTION

[0032] In order to keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of well-known functions and well-known components are omitted.

[0033] An embodiment of the present invention discloses a navigation system, which is used to assist doctors in performing neurosurgery for treating intracranial brain tissue lesions. Therefore, the navigation system can be specifically referred to as a neurosurgery (surgical) navigation system. The navigation system provided by the present invention and the navigation method to be described below are dedicated to navigating two intracranial operating instruments at the same time (navigating instruments can also be referred to as positioning and tracking instruments). Therefore, the navigation system and method provided by the present invention are suitable for neurosurgery that requires two intracranial operating instruments to be located in the skull at the same time to perform the surgical procedure.

[0034] The two intracranial operating instruments targeted for navigation by the navigation system and navigation method provided by the present invention have different functions in surgery. Specifically, one of the two intracranial operating instruments is used to perform removal operations such as resection and peeling on lesions of brain tissue (such as brain tumors), and the other instrument is not used to remove lesions but is used to perform auxiliary operations such as guidance, cleaning, and expansion. Furthermore, one of the two instruments (which may be referred to as the first instrument 31) belongs to a type of instrument whose distal end is likely to cause serious damage to brain tissue if it is not operated accurately, while the other instrument (which may be referred to as the second instrument 32) belongs to a type of instrument that will not cause serious damage to brain tissue even if it is not operated with high accuracy. For example, the first instrument 31 is an ultrasonic emulsification suction knife (such as a Cusa knife) used to remove brain tumors, and the second instrument 32 is a neuroendoscope used for guidance and expanding or enhancing the field of view.

[0035] like Figure 1 As shown, the navigation system provided by the present invention includes: an image acquisition device, a navigation instrument and a computer device 40.

[0036] Before the operation is performed, an image acquisition device is used to acquire an image for describing the anatomical structure of the patient's head. The image acquisition device may be: a computer tomography device (i.e., a CT device), a magnetic resonance imaging device (i.e., an MRI device), a positron emission tomography device (i.e., a PET device), or a digital subtraction angiography device (i.e., a DSA device). The image acquired by a single device may be directly used as an anatomical image for subsequent surgical path planning and navigation, or the images acquired by at least two of the devices may be fused using multimodal fusion technology to form an anatomical image. Figure 5 and Figure 6 As shown, the anatomical image is preferably a combined image, which includes but is not limited to: a three-dimensional image, a coronal image, a sagittal image, and a cross-sectional image, wherein the images provided by the above-mentioned devices can be used to construct a three-dimensional model of the head to obtain a three-dimensional image describing the head.

[0037] The navigation device includes: an optical navigation device 10 equipped with a camera 101, a first optical tracker 11, a second optical tracker 12, a third optical tracker 13, an electromagnetic navigation device 20 equipped with a magnetic field generator 23, and a first electromagnetic sensor 21. In some preferred embodiments, the navigation device further includes a second electromagnetic sensor 22.

[0038] At least three optical markers that are not in the same straight line are arranged on the first optical tracker 11, the second optical tracker 12, and the third optical tracker 13, and the optical markers can be identified by the camera 101 of the optical navigation device 10. In the preferred embodiment of the present invention, each optical tracker provided has four optical markers, and the optical markers are typical reflective balls that can be identified by the camera 101 by reflecting light (non-self-luminous). In this way, the optical navigation device 10 can use the camera 101 to take a picture of the optical tracker with the optical markers to obtain an image describing the optical tracker, and by analyzing the image, the position and posture of the optical tracker relative to the camera 101 can be obtained (the so-called position and posture specifically refers to the position and posture), so as to realize navigation of the instrument attached to the optical tracker, that is, based on the optical positioning and tracking principle (that is, the optical navigation principle), the optical navigation device 10 can realize navigation of the instrument by obtaining the position and posture of the optical tracker. The analysis and processing module and application program for analyzing the image to obtain the position and posture of the optical tracker may be integrated into the optical navigation device 10 or the computer device 40 mentioned above.

[0039] The magnetic field generator 23 in the electromagnetic navigation device 20 is used to generate an electromagnetic field. The first electromagnetic sensor 21 and the second electromagnetic sensor 22 are placed in the electromagnetic field generated by the magnetic field generator 23. The core components of the first electromagnetic sensor 21 and the second electromagnetic sensor 22 are electromagnetic coils. Based on the electromagnetic positioning and tracking principle (i.e., the electromagnetic navigation principle), the electromagnetic coil in the electromagnetic sensor is induced with a current in the electromagnetic field. The current is used as a parameter and the position and posture of the electromagnetic sensor relative to the magnetic field generator 23 can be obtained by analyzing the current. Among them, the analysis and processing module and application program for analyzing the current to obtain the position and posture of the electromagnetic sensor can be integrated in the electromagnetic navigation device 20, and can also be integrated in the above-mentioned computer device 40.

[0040] Before using an image acquisition device such as a CT device, an MRI device, etc. to acquire an image describing the anatomical structure of the patient's head, the first optical tracker 11 is fixedly attached to the patient's head, for example, the lower end of the first optical tracker 11 is screwed into the skull of the patient's head to fix the first optical tracker 11 to the patient's head, so that after the image of the anatomical structure of the patient's head is acquired by the image acquisition device, the first optical tracker 11 is also displayed in the image. In order to align the image of the first optical tracker 11 acquired by the camera 101 with the first optical tracker 11 in the image of the anatomical structure acquired by the image acquisition device and then to align the anatomical image in the optical coordinate system, the first optical tracker 11 needs to be configured with a marker that is easily recognized by the image acquisition device and can be enhanced in the acquired image describing the anatomical structure. Preferably, the marker is placed on the surface or the center of each reflective ball to reduce the difficulty of aligning the first optical tracker 11.

[0041] The second optical tracker 12 is fixedly and detachably attached to the proximal end (or outer end or handheld end) of the first instrument 31. Based on the structure and size of the second optical tracker 12 and the first instrument 31, there is a definite and known posture relationship between the second optical tracker 12 and the first instrument 31. The third optical tracker 13 is fixedly and detachably attached to the fixed device, preferably, attached to the top corner of the proximal side of the operating bed 50. Similarly, based on the structure and size of the third optical tracker 13 and the operating bed 50, there is a definite and known posture relationship between the third optical tracker 13 and the operating bed 50.

[0042] The optical navigation device 10 is arranged on one side of the operating table 50, and the camera 101 is arranged on the optical navigation device 10. Preferably, the optical navigation device 10 is also provided with a processing module for processing and analyzing the image taken by the camera 101 and finally obtaining the position and posture of the optical tracker, and a transmission module for communicating with the computer device 40. The specific arrangement position of the optical navigation device 10 must meet the following requirements: the patient's head and the surrounding area, the first optical tracker 11, the second optical tracker 12, and the third optical tracker are all located within the field of view of the camera 101, so that the positions and postures of the first optical tracker 11, the second optical tracker 12, and the third optical tracker can be obtained simultaneously and in real time.

[0043] The magnetic field generator 23 is arranged on the proximal side of the operating bed 50. Based on the structure and size of the magnetic field generator 23 and the operating bed 50, there is a definite and known posture relationship between the magnetic field generator 23 and the operating bed 50. Since there is a definite and known posture relationship between the third optical tracker 13 and the operating bed 50, there is a definite and known posture relationship between the magnetic field generator 23 and the third optical tracker 13. Specifically, a rectangular notch is configured on the proximal side of the operating bed 50, and the magnetic field generator 23 is installed in the notch, so that the magnetic field generator 23 is located directly below the head and its vicinity. Since the magnetic field generator 23 is installed in the notch, the magnetic field (magnetic flux lines) generated by the magnetic field generator 23 is less affected by the thickness of the operating bed 50. Preferably, the operating bed 50 is configured as a rectangular plate-like structure with uniform texture and thickness to reduce magnetic field distortion in local areas.

[0044] The first electromagnetic sensor 21 is attached to the second instrument 32 in a fixed and detachable manner. For example, the first electromagnetic sensor 21 is attached to the inner side of the tube wall of the distal region of the second instrument 32. For another example, the first electromagnetic sensor 21 is attached to the outer side of the tube wall of the proximal region of the second instrument 32. Based on the structure and size of the first electromagnetic sensor 21 and the second instrument 32, there is a determined and known posture relationship between the first electromagnetic sensor 21 and the second instrument 32. In the scheme configured with the second electromagnetic sensor 22, if the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32, the second electromagnetic sensor 22 is attached to the first instrument 31 in a fixed and detachable manner, so that during the operation, the result of the second electromagnetic sensor 22 and the first electromagnetic sensor 21 being as close as possible is obtained; if the first electromagnetic sensor 21 is attached to the proximal region of the second instrument 32, the second electromagnetic sensor 22 is attached to the first optical tracker 11 in the hope of being as close as possible to the first electromagnetic sensor 21. Based on the structure and size of the second electromagnetic sensor 22 and the device to which it is attached, there is also a determined and known posture relationship between the second electromagnetic sensor 22 and the device to which it is attached. In addition, the second electromagnetic sensor 22 can be placed in the micro-pan head 221, so that the posture of the second electromagnetic sensor 22 can be adjusted by the micro-pan head in real time and in a known manner.

[0045] A desktop computer and / or laptop computer with a display device 41 (e.g., a display) and a processing control device 42 (e.g., a host) in the prior art can be selected as the computer device 40, and the computer device 40 is integrated with an application based on a navigation system and a navigation method, and the application enables the computer device 40 to have the following display, storage and control functions.

[0046] The processing and control device 42 is used to store the following data: data of anatomical images describing the anatomical structure of the patient's head from the image acquisition device; data of the appearance structure and size of related instruments or equipment, for example, the appearance structure and size data of the operating table 50, the magnetic field generator 23, the camera 101, the first optical tracker 11, the second optical tracker 12, the third optical tracker 13, the first electromagnetic sensor 21, the second electromagnetic sensor 22, etc.; data of determined posture relationships of related instruments or equipment, for example, data of posture relationships between the second optical tracker 12 and the first instrument 31, between the third optical tracker 13 and the magnetic field generator 23, between the first electromagnetic sensor 21 and the second instrument 32, between the second electromagnetic sensor 22 and the first instrument 31 or the first optical tracker 11, etc.; data of pre-set coordinate systems representing the postures of related instruments or equipment and data of optical coordinate systems.

[0047] The processing and control device 42 is used to perform the following data reception, data processing and calculation: The processing and control device 42 is used to receive in real time the position and posture relationship data of the relevant instruments or equipment acquired by the optical navigation device 10 and the electromagnetic navigation device 20 .

[0048] The processing and control device 42 is used to calculate the posture of the relevant instruments or equipment in the optical coordinate system based on the stored determined posture relationship data between the instruments or equipment and the posture data of the relevant instruments or equipment obtained by the optical navigation device 10 and the electromagnetic navigation device 20. For example, the stored posture relationship data of the first instrument 31 relative to the second optical tracker 12 and the posture data of the second optical tracker 12 in the optical coordinate system obtained by the optical navigation device 10 are calculated to obtain the posture of the first instrument 31 in the optical coordinate system. For another example, the posture data of the third optical tracker 13 in the optical coordinate system obtained by the optical navigation device 10, the stored posture relationship data of the magnetic field generator 23 relative to the third optical tracker 13, and the posture data of the first electromagnetic sensor 21 relative to the magnetic field generator 23 obtained by the electromagnetic navigation device 20 are calculated to obtain the posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0049] The processing and control device 42 is also used to calculate the posture deviation data between the posture data of the instrument or device obtained completely based on the optical positioning tracking principle and the posture data of the instrument or device obtained based on the electromagnetic positioning tracking principle, and use this as calibration data to correct the posture deviation of the intracranial operation instrument.

[0050] The processing control device 42 is further used to align the first optical tracker 11 in the anatomical image with the first optical tracker 11 in the optical coordinate system acquired via the optical navigation device 10, thereby registering the anatomical image describing the anatomical structure of the patient's head in the optical coordinate system.

[0051] The processing and control device 42 is further used to display the two positioned and tracked intracranial operating instruments on the display device 41, thereby realizing visualization of the surgical process.

[0052] It should state: 1. In the present invention, by assigning a coordinate system to relevant instruments or devices, the posture relationship between the relevant instruments or devices is described by the posture relationship between the coordinate systems they belong to, which is consistent with the way in which the navigation system and method in the prior art describe the posture relationship.

[0053] 2. In the present invention, the optical coordinate system is made to coincide with the coordinate system of the camera 101 so as to reduce the amount of calculation caused by the coordinate system transformation as much as possible.

[0054] 3. In the present invention, the posture relationship between related instruments or equipment and the posture deviation of the same instrument or equipment are described by a transformation matrix, which is consistent with the way in which the navigation system and aspects in the prior art describe the posture relationship.

[0055] In the figures that use transformation matrices to describe the position and posture of related instruments or equipment, such as Figure 7 , 9 As shown in , 11, the coordinate system of the corresponding instrument or device is marked on the corresponding instrument or device, and the reference mark of the corresponding instrument or device is marked near the coordinate system, which not only represents the instrument or device itself, but also represents its coordinate system. Among them, the optical coordinate system is represented by the mark "0.

[0056] In the present invention, since the transformation matrix is ​​used to describe and calculate the posture relationship between instruments or devices and / or calibrate the posture deviation, it is necessary to define and explain the expression of the transformation matrix. In the expression of the transformation matrix in the following text and the accompanying drawings, "T" expresses the basic meaning of the matrix. The two numbers in the lower right corner of "T" are the reference marks of the two instruments or devices, separated by a comma, indicating that the transformation matrix represents the posture between the coordinate systems of the two instruments or devices. For example, Figure 7 As shown, the transformation matrix expression T 12,31 It represents the position and posture of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 , that is, it represents the position and posture of the first device 31 relative to the second optical tracker 12 .

[0057] In some expressions of the change matrix, there is no superscript in the upper right corner of "T". These matrix expressions represent the pose obtained only by the optical navigation device 10 based on the optical positioning tracking principle and / or the pose obtained by the determined pose relationship, for example, Figure 7 As shown, the transformation matrix expression T 0,12 represents the position of the coordinate system of the second optical tracker 12 acquired by the optical navigation device 10 in the optical coordinate system. For example, the transformation matrix expression T 12,31 represents the position and posture of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 obtained based on the determined position and posture relationship between the first device 31 and the second optical tracker 12. For example, the transformation matrix expression T 0,31 It represents the position T of the second optical tracker 12 in the optical coordinate system obtained by the optical navigation device 10. 0,12 The position and posture T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 obtained based on the determined position and posture relationship between the first device 31 and the second optical tracker 12 12,31 The position and orientation of the coordinate system of the first tool 31 obtained by calculation is obtained in the optical coordinate system.

[0058] In some expressions of the change matrix, there is a superscript "'" in the upper right corner of "T", which is recorded as "T'". These matrix expressions indicate that there is at least a position obtained by the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle, for example, Figure 7 As shown, the transformation matrix expression T' 23,21 represents the position of the coordinate system of the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23. For example, the transformation matrix expression T' 0,32 It represents: the position T of the coordinate system of the third optical tracker 13 in the optical coordinate system obtained by the optical navigation device 10 0,13 , a position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 obtained based on the determined position relationship between the magnetic field generator 23 and the third optical tracker 13 13,23 , the position T′ of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 obtained by the electromagnetic navigation device 20 23,21 , a posture T of the coordinate system of the second device 32 relative to the coordinate system of the first electromagnetic sensor 21 obtained based on the determined posture relationship between the second device 32 and the first electromagnetic sensor 21 21,32 The position and orientation of the coordinate system of the second device 32 obtained by calculation is obtained in the optical coordinate system.

[0059] In some expressions of change matrices, there is a superscript "''" at the upper right corner of "T", recorded as "T''". These matrix expressions indicate that for the same instrument or device, in the posture acquisition link, the posture deviation (or calibration posture) between the posture in the optical coordinate system obtained completely by the optical navigation device 10 based on the optical positioning tracking principle and / or the determined posture relationship and the posture in the optical coordinate system obtained by the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle is called a calibration (transformation) matrix. For example, Fig. 9 As shown, the calibration matrix, T'' 21,21 Represents the posture deviation between the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained by the optical navigation device 10 and the determined posture relationship and the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained by the optical navigation device 10, the determined posture relationship and the electromagnetic navigation device 20.

[0060] The present invention also discloses a method for implementing navigation for two intracranial operating instruments based on the above-mentioned navigation system. The functions of the two intracranial operating instruments for navigation during the operation are consistent with the functions of the operating instruments described above, that is, the first instrument 31 and the second instrument 32 are two different types of operating instruments. The role of the first instrument 31 during the operation is different from the role of the second instrument 32 during the operation. Furthermore, the first instrument 31 is an instrument whose distal end is likely to cause serious damage to brain tissue if it is not operated accurately, while the other instrument (which may be called the second instrument 32) is an instrument that will not cause serious damage to brain tissue even if it is not operated accurately. For example, the first instrument 31 is an ultrasonic emulsification suction knife (such as a Cusa knife) for removing brain tumors, and the second instrument 32 is a neuroendoscope for guiding and expanding or enhancing the field of view.

[0061] like Figure 2 As shown, the method for implementing navigation for two intracranial operation instruments disclosed in the present invention comprises the following steps: like Figure 3 As shown, S10: acquiring an anatomical image for describing the anatomical structure of the patient's head and having a first optical tracker 11 .

[0062] Before performing this step, the first optical tracker 11 is fixedly attached to the patient's head. For example, the lower end of the first optical tracker 11 is inserted into the skull, thereby fixing the first optical tracker 11 on the patient's head.

[0063] The anatomical image is acquired using a method and steps that are substantially consistent with the prior art. For example, the specific steps are as follows: S11: Obtain original medical images.

[0064] Specifically, the original medical images describing the anatomical structure of the patient's head are obtained by using devices such as CT equipment, MRI equipment, and PET equipment. Different modal images are selected according to the needs of the operation. For example, MRI images are obtained by using MRI equipment. Such images can show gray matter, white matter, tumors, blood vessels and other tissues with high resolution. The T1-weighted sequence in the MRI image can be used to segment brain tissue and for three-dimensional reconstruction, and the T2-weighted or FLAIR is used to show edema and the scope of the lesion.

[0065] S12: Processing the original medical image.

[0066] Specifically, the original medical image is processed individually or in combination as follows, and the processing contents include but are not limited to: denoising and standardization processing, for example, using processing software such as FSL and SPM to eliminate artifacts in the image; multimodal fusion and registration, for example, aligning and fusing images of types such as CT and MRI on the same seat; segmentation and three-dimensional reconstruction, for example, demarcating the structure of brain tissue, blood vessels and lesion areas (for example, tumors) and constructing a three-dimensional model. During segmentation, the optical tracker in the image (not the first optical tracker 11 in the present invention) is separately segmented, and its purpose is: after the anatomical image is registered in the optical coordinate system using the optical tracker, the optical tracker is hidden in the anatomical image to avoid it from obscuring the cranial entrance, the target area (lesion area), the surgical path, etc.; adjusting display parameters, for example, adjusting brightness, contrast, and adding highlight values ​​to highlight the lesion area in the skull.

[0067] S13: Convert and unify the output format of anatomical images.

[0068] Specifically, the post-processed anatomical image is converted into a format that can be recognized and processed by an application in the processing control device 42 of the computer device 40, for example, the format of the anatomical image is converted into a DICOM format, so that it can be used in the application of the navigation system and can be displayed in the display device 41 ( Figure 5 and Figure 6 ) shows an anatomical image displayed on the display device 41.

[0069] like Figure 4 As shown, S20: marking the target area, cranial entrance, and surgical path in the anatomical image to guide the intracranial operating instrument (ie, surgical instrument) to enter the skull through the cranial entrance and reach the target area along the surgical path.

[0070] In this step, the following processes are specifically included: S21: Preliminarily plan a surgical approach based on the acquired anatomical image describing the patient's head.

[0071] First, before planning the approach, the nature, location, and boundaries of the lesion must be clarified. Figure 5 and Figure 6 The anatomical image shown (the first optical tracker 11 and the coordinate system of the image are hidden in the image) clearly shows that the lesion is a glioma. The position and boundary of the glioma can be determined through three-dimensional images and sagittal images, coronal images, and cross-sectional images, and its boundary can be enhanced by outlining solid lines (or dotted lines).

[0072] Then, the surgical approach is preliminarily planned based on the nature, location, and boundaries of the lesion. When planning the surgical approach, issues such as avoiding the functional areas of the brain tissue and avoiding blood vessels need to be considered.

[0073] Targeted resection Figure 5 and Figure 6 Taking the glioma on the insular lobe as an example, this step exemplarily provides two surgical approach options.

[0074] The first surgical approach plan: based on the location and boundaries of the glioma shown in anatomical images including three-dimensional images and sagittal images, coronal images, and cross-sectional images, and after comprehensively predicting the functional areas and blood vessels of the brain tissue that the glioma may pass through at different cranial entrances, as well as the difficulty of reaching the glioma at different angles, the approach plan is determined as follows: Figure 5 As shown, the operating instrument enters through the sylvian fissure or the opercular cortex and removes the glioma from the top to the bottom. The advantage of this approach is that the distance from the lateral cortex to the glioma in the insula is shorter, but the instrument needs to pass through the sylvian fissure venous network of the cortex, the functional area of ​​the opercular cortex, and the middle cerebral artery network crawling on the surface of the insula. Glioma resection needs to avoid arteries, veins and functional areas. Therefore, this approach limits the spatial angle of surgical operation, increases the difficulty of the operation and the probability of damaging important structures.

[0075] The second surgical approach is based on the location and boundaries of the glioma shown in anatomical images including three-dimensional images, sagittal images, coronal images, and cross-sectional images, and after comprehensively predicting the difficulty of reaching the functional areas and blood vessels of the brain tissue that the glioma may pass through at different cranial entrances and reaching the glioma at different angles. Figure 6As shown in the figure, the operating instrument enters the insula from the frontal part, reaches the insular glioma through the frontal isthmus, and removes the glioma from the bottom to the top of the glioma. Although this approach to enter the insula from the frontal side has a longer surgical path, it bypasses the sylvian fissure vein, the functional area of ​​the opercular cortex, and the middle cerebral artery network, avoiding damage to these important structures. Compared with the first approach, the advantages of this approach are: it reduces the disturbance of the sylvian fissure vein and the middle cerebral artery network, reduces the risk of vascular spasm and injury; it avoids the language, motor, and sensory functional areas of the opercular cortex, and reduces the dependence on electrophysiological monitoring during surgery; the removal of the insular glioma from the frontal direction is along the long axis of the glioma, and there is no need to adjust the surgical angle in a large range. The field of view can cover the entire glioma, which improves the glioma resection rate.

[0076] S22: Accurately plan the cranial entrance and the approach path in the anatomical image according to the initially planned approach plan using the optical navigation probe. S30: Obtain the position of the first optical tracker 11 in the optical coordinate system using the optical navigation device 10, and register the anatomical image in the optical coordinate system based on the position of the first optical tracker 11 in the optical coordinate system and the position of the first optical tracker 11 in the image coordinate system of the anatomical image.

[0077] The image obtained by photographing the first optical tracker 11 through the camera 101 of the optical navigation device 10 has relative position information of four reflective balls, and the relative position information of four markers consistent with the relative positions of the four reflective balls are prominently displayed in the anatomical image describing the anatomical structure of the head. In this way, the relative positions of the four markers in the anatomical image can be aligned with the relative positions of the four reflective balls in the image acquired by the camera 101, thereby completing the alignment of the first optical tracker 11 in the anatomical image and the first optical tracker 11 in the optical coordinate system, thereby realizing the registration of the anatomical image in the optical coordinate system.

[0078] S40: Use the optical navigation device 10 to obtain the position and posture of the second optical tracker 12 in the optical coordinate system; use the optical navigation device 10 to obtain the position and posture of the third optical tracker 13 in the optical coordinate system and use the electromagnetic navigation device 20 to obtain the position and posture of the first electromagnetic sensor 21 relative to the magnetic field generator 23; based on the position and posture of the third optical tracker 13 in the optical coordinate system, the position and posture relationship between the magnetic field generator 23 and the third optical tracker 13, and the position and posture of the first electromagnetic sensor 21 relative to the magnetic field generator 23, the position and posture of the first electromagnetic sensor 21 in the optical coordinate system is obtained.

[0079] The purpose of this step is to simultaneously (or synchronously) obtain the positions and postures of the second optical tracker 12 and the first electromagnetic sensor 21 in the optical coordinate system. As a result, the positions and postures of the first instrument 31 and the second instrument 32 in the optical coordinate system can be obtained simultaneously based on the determined position and posture relationship between the first instrument 31 and the second optical tracker 12 and the determined position and posture relationship between the second instrument 32 and the first electromagnetic sensor 21. Ultimately, when the second instrument 32 is not equipped with an optical tracker, the positioning and tracking (i.e., navigation) of the two intracranial operating instruments (i.e., the first instrument 31 and the second instrument 32) can be achieved.

[0080] The method for obtaining the posture of the second optical tracker 12 in the optical coordinate system is: using the optical navigation device 10 and directly obtaining the posture T of the coordinate system of the second optical tracker 12 in the optical coordinate system based on the optical positioning tracking principle. 0,12 .

[0081] like Figure 7 As shown, the method for obtaining the posture of the first electromagnetic sensor 21 in the optical coordinate system is: first, using the optical navigation device 10 and based on the optical positioning tracking principle, obtain the posture T of the coordinate system of the third optical tracker 13 in the optical coordinate system. 0,13 And using the electromagnetic navigation device 20 and based on the electromagnetic positioning tracking principle, the position T' of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 is obtained. 23,21 Then, using the processing control device 42, the coordinate system of the third optical tracker 13 is positioned in the optical coordinate system T 0,13 , the position T of the coordinate system of the magnetic field generator 23 stored in the processing control device 42 relative to the coordinate system of the third optical tracker 13 13,23 , the position T' of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 23,21 The posture T' of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation. 0,21 , that is, T' 0,21 =T 0,13 *T 13,23 *T' 23,21 .

[0082] The notable feature of this step is that navigation is simultaneously implemented on the first device 31 and the second device 32 by operating the electromagnetic navigation device 20 and the optical navigation device 10 simultaneously, and navigation of the second device 32 is implemented by the method that the optical navigation device 10 and the electromagnetic navigation device 20 cooperate to obtain the position and posture of the first electromagnetic sensor 21 in the optical coordinate system, thereby avoiding navigation of the second device 32 by configuring an optical tracker on the second device 32. As there is no need to configure an optical tracker on the second device 32, the probability of the second optical tracker 12 on the first device 31 being shielded by the second device 32 and the probability of mutual mechanical interference are significantly reduced, thereby reducing the probability of interruption of navigation of the operating device due to shielding and significantly improving the activity range of the two operating devices.

[0083] S50: Calibrate the position and posture of the first electromagnetic sensor 21.

[0084] like Figures 8 to 11 Combined with Figure 7 As shown, when obtaining the position T' of the first electromagnetic sensor 21 in the optical coordinate system 0,21 In the process, due to the existence of the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle to obtain the first electromagnetic sensor 21 relative to the magnetic field generator 23 posture T' 23,21 Although the present invention reduces or minimizes magnetic field distortion and posture deviation caused by magnetic field distortion by configuring a homogeneous operating table 50 and arranging the magnetic field generator 23 on the front side of the operating table 50 near the head, the magnetic field distortion cannot be completely eliminated, resulting in deviation in the posture obtained based on the electromagnetic positioning tracking principle. Therefore, in the process of navigating the first instrument 31 and the second instrument 32, the posture T' of the coordinate system of the first electromagnetic sensor 21 on the second instrument 32 in the optical coordinate system can be 0,21 Perform calibration. The calibration method can be summarized as follows: Get the calibration matrix T'' 21,21 , using the processing control device 42 to change the coordinate system of the first electromagnetic sensor 21 to the position T' in the optical coordinate system 0,21 With the calibration matrix T' 0,21 The calibrated pose T' is obtained by calculation 0,21 *T'' 21,21 , the position T' of the coordinate system of the calibrated first electromagnetic sensor 21 in the optical coordinate system 0,21 *T'' 21,21 Compared with the pose T' before calibration 0,21 More accurate, thereby improving the navigation accuracy of the second instrument 32. Two specific methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0085] S60: Based on the posture of the second optical tracker 12 in the optical coordinate system and the posture relationship between the second optical tracker 12 and the first instrument 31, the posture of the first instrument 31 in the optical coordinate system is obtained; based on the calibrated posture of the first electromagnetic sensor 21 in the optical coordinate system and the posture relationship between the first electromagnetic sensor 21 and the second instrument 32, the calibrated posture of the second instrument 32 in the optical coordinate system is obtained; based on the obtained postures, the first instrument 31 and the second instrument 32 are navigated and visualized in the anatomical image.

[0086] Specifically, the acquired coordinate system of the second optical tracker 12 is converted into the position T of the optical coordinate system by using the processing control device 42. 0,12 The position T of the coordinate system of the first instrument 31 relative to the coordinate system of the second optical tracker 12 stored in the processing control device 42 12,31 The position T of the coordinate system of the first device 31 in the optical coordinate system is obtained by calculation. 0,31 =T 0,12 *T 12,31 ; The calibrated first electromagnetic sensor 21 coordinate system in the optical coordinate system posture T ' 0,21 *T'' 21,21 The position T of the coordinate system of the second device 32 relative to the coordinate system of the first electromagnetic sensor 21 stored in the processing control device 42 21,32 The position T′ of the coordinate system of the calibrated first instrument 31 in the optical coordinate system is obtained by calculation. 0,21 *T'' 21,21 *T 21,32 .

[0087] In the display device 41, based on the obtained postures of the first instrument 31 and the second instrument 32, navigation is performed on the first instrument 31 and the second instrument 32, and the first instrument 31 and the second instrument 32 unified in the optical coordinate system are displayed in an anatomical image describing the anatomical structure of the head to achieve visualization of the first instrument 31 and the second instrument 32 in the anatomical image.

[0088] Two methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0089] like Figure 8 and Fig. 9 As shown, a first method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0090] Before implementing this method, the first device 31 and the second device 32 need to be configured into the following mechanical matching mode: The first instrument 31 and the second instrument 32 can be rigidly and detachably attached, and in the attached state, the first instrument 31 and the second instrument 32 have a certain posture relationship.

[0091] In order to achieve the above-mentioned cooperation mode, the first device 31 and the second device 32 are additionally provided with the following structures: A first positioning structure is configured on the first instrument 31, and a second positioning structure is configured on the second instrument 32. The first instrument 31 and the second instrument 32 can be detachably attached via the first positioning structure and the second positioning structure. Specifically, two first positioning rings each having a positioning recess are fixedly sleeved on the outer circumference of the proximal region of the first instrument 31, and two first positioning rings each having a positioning protrusion are fixedly sleeved on the outer circumference of the proximal region of the second instrument 32. The two positioning protrusions are correspondingly inserted into the two positioning recesses, so that the first instrument 31 and the second instrument 32 are attached in a rigid, detachable manner with a certain posture relationship, and data on the posture relationship between the first instrument 31 and the second instrument 32 are stored in the processing and control device 42.

[0092] like Figure 8 and Fig. 9 As shown, the first method provided by the present invention for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system includes the following steps: S51: Obtaining the posture of the first electromagnetic sensor 21 relative to the second optical tracker 12 based on the posture relationship between the first device 31 and the second device 32 in the attached state.

[0093] Specifically, at least before the distal ends of the first instrument 31 and the second instrument 32 enter the skull through the cranial entrance, the first instrument 31 and the second instrument 32 are attached once. In the attached state, due to the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second instrument 32, 32,21 , the position T of the coordinate system of the second instrument 32 relative to the coordinate system of the first instrument 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 is known and pre-stored in the processing control device 42. Therefore, the processing control device 42 is used to convert the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 into 32,21 , the position T of the coordinate system of the second device 32 relative to the coordinate system of the first device 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 can be obtained by calculation. 12,21 =T32,21 *T 31,32 *T 12,31 .

[0094] Preferably, if Fig. 9 As shown, the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. For example, the first electromagnetic sensor 21 is attached to the inner side of the tube wall in the distal region. If the first electromagnetic sensor 21 can be arranged in the distal region of the second instrument 32, then after the distal transcranial entrance of the first instrument 31 and the second instrument 32 reaches the intracranial lesion and before the lesion is treated, the first instrument 31 and the second instrument 32 can be attached again. The advantage of attaching the first instrument 31 and the second instrument 32 again at this stage will be explained below.

[0095] S52: Taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the first electromagnetic sensor 21 in the attached state relative to the second optical tracker 12 and the posture of the second optical tracker 12 in the optical coordinate system acquired by the optical navigation device 10 as the reference posture.

[0096] Specifically, in the attached state, the obtained position and posture T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 is calculated by the processing control device 42. 12,21 The position T of the coordinate system of the second optical tracker 12 obtained by the optical navigation device in the optical coordinate system 0,12 The position T of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation. 0,21 = T 12,21 * T 0,12 , the pose T 0,21 as the reference pose.

[0097] It should be noted that this step and the reference posture described below are all obtained by calculating the posture obtained by the optical navigation device 10 based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship between related instruments or equipment. The reason for using the posture obtained by calculating the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship as the reference posture is that the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship are more accurate than the posture obtained by the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle. Therefore, the reference posture is used as the reference for calibrating the posture.

[0098] S53: The posture of the third optical tracker 13 in the optical coordinate system obtained by the optical navigation device 10 in the attached state, the posture relationship between the magnetic field generator 23 and the third optical tracker 13, and the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained by the electromagnetic navigation device 20 relative to the magnetic field generator 23 are taken as the posture to be calibrated.

[0099] Specifically, in the attached state, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into a position T in the optical coordinate system. 0,13 , the position T of the coordinate system of the magnetic field generator 23 stored in the processing device relative to the coordinate system of the third optical tracker 13 13,23 , the position T′ of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 obtained by the electromagnetic navigation device 20 23,21 The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,13 * T 13,23 * T' 23,21 , since the position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system 0,21 There is a method to obtain the position T' based on the electromagnetic positioning tracking principle 23,21 In the link, due to the distortion of the magnetic field, the posture obtained based on the electromagnetic positioning tracking principle has deviations, so the posture T' 0,21 As the posture to be calibrated.

[0100] S54: obtaining a calibration matrix based on the to-be-calibrated posture of the first electromagnetic sensor 21 and the reference posture, and calibrating the posture of the first electromagnetic sensor 21 in the optical coordinate system using the calibration matrix.

[0101] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the first electromagnetic sensor 21 into a reference position T in the optical coordinate system. 0,21 The coordinate system of the first electromagnetic sensor 21 to be calibrated in the optical coordinate system is T' 0,21 The calibration matrix T'' is obtained by calculation 21,21 = T 0,21 * (- T' 0,21 ), then, the calibration matrix T'' 21,21 The position and posture of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system are calculated in real time, so that the position and posture of the first electromagnetic sensor 21 and the second device 32 are calibrated in real time.

[0102] In fact, the calibration matrix obtained by the above method characterizes and quantifies the difference between the distorted magnetic field and the preset magnetic field to a certain extent. For example, the calibration matrix characterizes and quantifies the difference in density of magnetic flux lines before and after local distortion or the overall offset of magnetic flux lines before and after magnetic field offset to a certain extent. Therefore, the process of posture calibration is also the process of correcting magnetic field distortion. In this way, when the second instrument 32 cooperates with the first instrument 31 to perform a treatment operation on the lesion, by using the calibration matrix T'' 21,21 The first electromagnetic sensor 21 and the second device 32 are calibrated to improve the accuracy of navigation of the second device 32 to a certain extent.

[0103] The advantage of the above-mentioned preference to attach the first electromagnetic sensor 21 to the distal region of the second instrument 32, and preferably to attach the first instrument 31 and the second instrument 32 again after the distal ends of the first instrument 31 and the second instrument 32 reach the intracranial lesion through the cranial entrance and before treating the lesion to obtain the calibration matrix of the magnetic field region where the first electromagnetic sensor 21 is located (the region where the lesion is located) is that, in fact, when treating the lesion, accurate positioning and tracking of the distal ends of the two operating instruments is the key to accurately treating the lesion. If the first electromagnetic sensor 21 is arranged at the proximal end of the second instrument 32, because the two intracranial operating instruments are rod-shaped instruments, the distance between the first electromagnetic sensor 21 and the distal end is relatively large, and because the second instrument 32 inevitably depends on the calibration after calibration. However, there is a posture deviation (the posture deviation of the instrument calibrated by the calibration matrix is ​​reduced and difficult to completely eliminate), therefore, the posture deviation of the second instrument 32 after calibration will increase after being converted to the distal end, and if the first electromagnetic sensor 21 is arranged near the distal end of the second instrument 32, the position deviation will not change much after conversion to the end; the reason for calibrating the second instrument 32 again after reaching the lesion is that the magnetic field distortion in the lesion area may be different from that in its peripheral area (such as the extracranial area), and the calibration matrix obtained may be different. Using the calibration matrix obtained near the lesion area to calibrate the first instrument 31 for the treatment operation is beneficial to reducing the posture deviation of the first instrument 31 during the treatment operation.

[0104] A second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0105] Before implementing this method, a second electromagnetic sensor 22 for acquiring posture based on the electromagnetic positioning tracking principle is arranged on the first instrument 31 or in an area having a certain posture relationship with the first optical tracker 11 (e.g., directly on the first optical tracker 11 or on the patient's head).

[0106] like Fig.10 and Fig.11As shown, the second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system provided by the present invention includes the following steps: S51 ′: taking the position and posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the position and posture of the first optical tracker 11 or the second optical tracker 12 in the optical coordinate system as a reference position and posture of the second electromagnetic sensor 22 .

[0107] In this step, the reference position of the second electromagnetic sensor 22 in the optical coordinate system can be obtained in two ways.

[0108] The first method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the second optical tracker 12 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first device 31 in advance with a determined position relationship, and the position of the coordinate system of the second optical tracker 12 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position T by the processing control device 42. 0,12 The position T of the second electromagnetic sensor 22 relative to the second optical tracker 12 12,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 = T 0,12 * T 12,22 In this embodiment, the second electromagnetic sensor 22 is preferably attached to the distal region of the first instrument 31, and the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. The advantages of arranging the two electromagnetic sensors in this way will be described below.

[0109] The second method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the first optical tracker 11 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 (or to the head of a patient with a determined position relationship with the first optical tracker 11) in advance at a determined position relationship, and the position T of the coordinate system of the first optical tracker 11 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position of the second electromagnetic sensor 22 in the optical coordinate system by the processing control device 42. 0,11 The position T of the coordinate system of the second electromagnetic sensor 22 relative to the coordinate system of the first optical tracker 11 11,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 =T 0,11 * T 11,22 In this embodiment, specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 , and the first electromagnetic sensor 21 is attached to the proximal region of the second instrument 32 , in the hope of being as close to the first electromagnetic sensor 21 as possible.

[0110] S52′: taking the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the second electromagnetic sensor 22 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the second electromagnetic sensor 22.

[0111] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13 The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the second electromagnetic sensor 22 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,22 The position T' of the coordinate system of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation 0,22 = T 0,23 * T' 23,22 , and use this posture as the posture to be calibrated for the second electromagnetic sensor 22.

[0112] S53 ′: taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the first electromagnetic sensor 21 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the first electromagnetic sensor 21 .

[0113] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13 The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,21The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,23 * T' 23,21 , and use this posture as the posture to be calibrated of the first electromagnetic sensor 21.

[0114] S54 ′: obtaining a calibration matrix based on the to-be-calibrated posture of the second electromagnetic sensor 22 and the reference posture, and calibrating the to-be-calibrated posture of the first electromagnetic sensor 21 using the calibration matrix.

[0115] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the second electromagnetic sensor 22 into a reference position T in the optical coordinate system. 0,22 The coordinate system of the second electromagnetic sensor 22 to be calibrated in the optical coordinate system is T' 0,22 The calibration matrix T'' is obtained by calculation 22,22 = T 0,22 * (-T' 0,22 ), then, the calibration matrix T'' 22,22 The real-time calculation T' is performed on the position of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system obtained in real time. 0,21 =T' 0,21 *T'' 22,22 , thereby calibrating the position and posture of the first electromagnetic sensor 21 and the second device 32 in real time.

[0116] The principle of calibrating the posture of the first electromagnetic sensor 21 in this method can be summarized as follows: the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based only on the optical positioning tracking principle and the determined posture relationship is calculated with the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained with the participation of the electromagnetic tracking positioning principle to obtain a calibration matrix, and then the calibration matrix is ​​used to calibrate the posture of the first electromagnetic sensor 21. More generally speaking: the posture deviation of the second electromagnetic sensor 22 between the two posture acquisition methods is used as the calibration matrix 2 to calibrate the posture of the first electromagnetic sensor 21.

[0117] In the second calibration method, the first method is superior to the second method, and the reason is that in the first method, the two electromagnetic sensors can be arranged in the distal area of ​​the two instruments. In this way, the positions of the two electromagnetic sensors are close, and the two electromagnetic sensors are basically (or, with a high probability) in the magnetic field area with the same distortion. Therefore, the posture deviation of the second electromagnetic sensor 22 is highly consistent with the posture deviation of the first electromagnetic sensor 21. Therefore, the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 has a high accuracy in calibrating the posture of the first electromagnetic sensor 21. However, in the second method, since the second electromagnetic sensor 22 is arranged on the first optical tracker 11 (or, the patient's head), the positions of the first electromagnetic sensor 21 and the second electromagnetic sensor 22 located on the second instrument 32 are far apart, which results in that the distortion of the magnetic field areas where the first electromagnetic sensor 21 and the second electromagnetic sensor 22 are located may be different, which may cause the calibration accuracy of the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 for the first electromagnetic sensor 21 to be lower than that of the first method.

[0118] In the second method, the second electromagnetic sensor 22 can be configured in the WeChat gimbal, and the micro-driving component (such as a micro-motor) in the WeChat gimbal drives the second electromagnetic sensor 22 to adjust its posture, so that the posture of the second electromagnetic sensor 22 is consistent with the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 in real time in the optical coordinate system, and thus the first electromagnetic sensor 21 is calibrated based on the calibration matrix obtained by the second electromagnetic sensor 22, which is conducive to reducing the reduction in calibration accuracy caused by the excessive spatial angle of the two electromagnetic sensors. S50: Calibrate the posture of the first electromagnetic sensor 21.

[0119] like Figures 8 to 11 Combined with Figure 7 As shown, when obtaining the position T' of the first electromagnetic sensor 21 in the optical coordinate system 0,21 In the process, due to the existence of the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle to obtain the first electromagnetic sensor 21 relative to the magnetic field generator 23 posture T' 23,21 Although the present invention reduces or minimizes magnetic field distortion and posture deviation caused by magnetic field distortion by configuring a homogeneous operating table 50 and arranging the magnetic field generator 23 on the front side of the operating table 50 near the head, the magnetic field distortion cannot be completely eliminated, resulting in deviation in the posture obtained based on the electromagnetic positioning tracking principle. Therefore, in the process of navigating the first instrument 31 and the second instrument 32, the posture T' of the coordinate system of the first electromagnetic sensor 21 on the second instrument 32 in the optical coordinate system can be 0,21 Perform calibration. The calibration method can be summarized as follows: Get the calibration matrix T'' 21,21, using the processing control device 42 to change the coordinate system of the first electromagnetic sensor 21 to the position T' in the optical coordinate system 0,21 With the calibration matrix T' 0,21 The calibrated pose T' is obtained by calculation 0,21 *T'' 21,21 , the position T' of the coordinate system of the calibrated first electromagnetic sensor 21 in the optical coordinate system 0,21 *T'' 21,21 Compared with the pose T' before calibration 0,21 More accurate, thereby improving the navigation accuracy of the second instrument 32. Two specific methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0120] S60: Based on the posture of the second optical tracker 12 in the optical coordinate system and the posture relationship between the second optical tracker 12 and the first instrument 31, the posture of the first instrument 31 in the optical coordinate system is obtained; based on the calibrated posture of the first electromagnetic sensor 21 in the optical coordinate system and the posture relationship between the first electromagnetic sensor 21 and the second instrument 32, the calibrated posture of the second instrument 32 in the optical coordinate system is obtained; based on the obtained postures, the first instrument 31 and the second instrument 32 are navigated and visualized in the anatomical image.

[0121] Specifically, the acquired coordinate system of the second optical tracker 12 is converted into the position T of the optical coordinate system by using the processing control device 42. 0,12 The position T of the coordinate system of the first instrument 31 relative to the coordinate system of the second optical tracker 12 stored in the processing control device 42 12,31 The position T of the coordinate system of the first device 31 in the optical coordinate system is obtained by calculation. 0,31 =T 0,12 *T 12,31 ; The calibrated first electromagnetic sensor 21 coordinate system in the optical coordinate system posture T ' 0,21 *T'' 21,21 The position T of the coordinate system of the second device 32 relative to the coordinate system of the first electromagnetic sensor 21 stored in the processing control device 42 21,32 The position T′ of the coordinate system of the calibrated first instrument 31 in the optical coordinate system is obtained by calculation. 0,21 *T'' 21,21 *T 21,32 .

[0122] In the display device 41, based on the obtained postures of the first instrument 31 and the second instrument 32, navigation is performed on the first instrument 31 and the second instrument 32, and the first instrument 31 and the second instrument 32 unified in the optical coordinate system are displayed in an anatomical image describing the anatomical structure of the head to achieve visualization of the first instrument 31 and the second instrument 32 in the anatomical image.

[0123] Two methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0124] like Figure 8 and Fig. 9 As shown, a first method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0125] Before implementing this method, the first device 31 and the second device 32 need to be configured into the following mechanical matching mode: The first instrument 31 and the second instrument 32 can be rigidly and detachably attached, and in the attached state, the first instrument 31 and the second instrument 32 have a certain posture relationship.

[0126] In order to achieve the above-mentioned cooperation mode, the first device 31 and the second device 32 are additionally provided with the following structures: A first positioning structure is configured on the first instrument 31, and a second positioning structure is configured on the second instrument 32. The first instrument 31 and the second instrument 32 can be detachably attached via the first positioning structure and the second positioning structure. Specifically, two first positioning rings each having a positioning recess are fixedly sleeved on the outer circumference of the proximal region of the first instrument 31, and two first positioning rings each having a positioning protrusion are fixedly sleeved on the outer circumference of the proximal region of the second instrument 32. The two positioning protrusions are correspondingly inserted into the two positioning recesses, so that the first instrument 31 and the second instrument 32 are attached in a rigid, detachable manner with a certain posture relationship, and data on the posture relationship between the first instrument 31 and the second instrument 32 are stored in the processing and control device 42.

[0127] like Figure 8 and Fig. 9 As shown, the first method provided by the present invention for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system includes the following steps: S51: Obtaining the posture of the first electromagnetic sensor 21 relative to the second optical tracker 12 based on the posture relationship between the first device 31 and the second device 32 in the attached state.

[0128] Specifically, at least before the distal ends of the first instrument 31 and the second instrument 32 enter the skull through the cranial entrance, the first instrument 31 and the second instrument 32 are attached once. In the attached state, due to the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second instrument 32, 32,21 , the position T of the coordinate system of the second instrument 32 relative to the coordinate system of the first instrument 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 is known and pre-stored in the processing control device 42. Therefore, the processing control device 42 is used to convert the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 into 32,21 , the position T of the coordinate system of the second instrument 32 relative to the coordinate system of the first instrument 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 can be obtained by calculation. 12,21 =T 32,21 *T 31,32 *T 12,31 .

[0129] Preferably, if Fig. 9 As shown, the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. For example, the first electromagnetic sensor 21 is attached to the inner side of the tube wall in the distal region. If the first electromagnetic sensor 21 can be arranged in the distal region of the second instrument 32, then after the distal transcranial entrance of the first instrument 31 and the second instrument 32 reaches the intracranial lesion and before the lesion is treated, the first instrument 31 and the second instrument 32 can be attached again. The advantage of attaching the first instrument 31 and the second instrument 32 again at this stage will be explained below.

[0130] S52: Taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the first electromagnetic sensor 21 in the attached state relative to the second optical tracker 12 and the posture of the second optical tracker 12 in the optical coordinate system acquired by the optical navigation device 10 as the reference posture.

[0131] Specifically, in the attached state, the obtained position and posture T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 is calculated by the processing control device 42. 12,21 The position T of the coordinate system of the second optical tracker 12 obtained by the optical navigation device in the optical coordinate system 0,12 The position T of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation. 0,21= T 12,21 * T 0,12 , the pose T 0,21 as the reference pose.

[0132] It should be noted that this step and the reference posture described below are all obtained by calculating the posture obtained by the optical navigation device 10 based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship between related instruments or equipment. The reason for using the posture obtained by calculating the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship as the reference posture is that the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship are more accurate than the posture obtained by the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle. Therefore, the reference posture is used as the reference for calibrating the posture.

[0133] S53: The posture of the third optical tracker 13 in the optical coordinate system obtained by the optical navigation device 10 in the attached state, the posture relationship between the magnetic field generator 23 and the third optical tracker 13, and the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained by the electromagnetic navigation device 20 relative to the magnetic field generator 23 are taken as the posture to be calibrated.

[0134] Specifically, in the attached state, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into a position T in the optical coordinate system. 0,13 , the position T of the coordinate system of the magnetic field generator 23 stored in the processing device relative to the coordinate system of the third optical tracker 13 13,23 , the position T′ of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 obtained by the electromagnetic navigation device 20 23,21 The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,13 * T 13,23 * T' 23,21 , since the position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system 0,21 There is a method to obtain the position T' based on the electromagnetic positioning tracking principle 23,21 In the link, due to the distortion of the magnetic field, the posture obtained based on the electromagnetic positioning tracking principle has deviations, so the posture T' 0,21 As the posture to be calibrated.

[0135] S54: obtaining a calibration matrix based on the to-be-calibrated posture of the first electromagnetic sensor 21 and the reference posture, and calibrating the posture of the first electromagnetic sensor 21 in the optical coordinate system using the calibration matrix.

[0136] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the first electromagnetic sensor 21 into a reference position T in the optical coordinate system. 0,21 The coordinate system of the first electromagnetic sensor 21 to be calibrated in the optical coordinate system is T' 0,21 The calibration matrix T'' is obtained by calculation 21,21 = T 0,21 * (- T' 0,21 ), then, the calibration matrix T'' 21,21 The position and posture of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system are calculated in real time, so that the position and posture of the first electromagnetic sensor 21 and the second device 32 are calibrated in real time.

[0137] In fact, the calibration matrix obtained by the above method characterizes and quantifies the difference between the distorted magnetic field and the preset magnetic field to a certain extent. For example, the calibration matrix characterizes and quantifies the difference in density of magnetic flux lines before and after local distortion or the overall offset of magnetic flux lines before and after magnetic field offset to a certain extent. Therefore, the process of posture calibration is also the process of correcting magnetic field distortion. In this way, when the second instrument 32 cooperates with the first instrument 31 to perform a treatment operation on the lesion, by using the calibration matrix T'' 21,21 The first electromagnetic sensor 21 and the second device 32 are calibrated to improve the accuracy of navigation of the second device 32 to a certain extent.

[0138] The advantage of the above-mentioned preference to attach the first electromagnetic sensor 21 to the distal region of the second instrument 32, and preferably to attach the first instrument 31 and the second instrument 32 again after the distal ends of the first instrument 31 and the second instrument 32 reach the intracranial lesion through the cranial entrance and before treating the lesion to obtain the calibration matrix of the magnetic field region where the first electromagnetic sensor 21 is located (the region where the lesion is located) is that, in fact, when treating the lesion, accurate positioning and tracking of the distal ends of the two operating instruments is the key to accurately treating the lesion. If the first electromagnetic sensor 21 is arranged at the proximal end of the second instrument 32, because the two intracranial operating instruments are rod-shaped instruments, the distance between the first electromagnetic sensor 21 and the distal end is relatively large, and because the second instrument 32 inevitably depends on the calibration after calibration. However, there is a posture deviation (the posture deviation of the instrument calibrated by the calibration matrix is ​​reduced and difficult to completely eliminate), therefore, the posture deviation of the second instrument 32 after calibration will increase after being converted to the distal end, and if the first electromagnetic sensor 21 is arranged near the distal end of the second instrument 32, the position deviation will not change much after conversion to the end; the reason for calibrating the second instrument 32 again after reaching the lesion is that the magnetic field distortion in the lesion area may be different from that in its peripheral area (such as the extracranial area), and the calibration matrix obtained may be different. Using the calibration matrix obtained near the lesion area to calibrate the first instrument 31 for the treatment operation is beneficial to reducing the posture deviation of the first instrument 31 during the treatment operation.

[0139] A second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0140] Before implementing this method, a second electromagnetic sensor 22 for acquiring posture based on the electromagnetic positioning tracking principle is arranged on the first instrument 31 or in an area having a certain posture relationship with the first optical tracker 11 (e.g., directly on the first optical tracker 11 or on the patient's head).

[0141] like Fig.10 and Fig.11 As shown, the second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system provided by the present invention includes the following steps: S51 ′: taking the position and posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the position and posture of the first optical tracker 11 or the second optical tracker 12 in the optical coordinate system as a reference position and posture of the second electromagnetic sensor 22 .

[0142] In this step, the reference position of the second electromagnetic sensor 22 in the optical coordinate system can be obtained in two ways.

[0143] The first method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the second optical tracker 12 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first device 31 in advance with a determined position relationship, and the position of the coordinate system of the second optical tracker 12 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position T by the processing control device 42. 0,12 The position T of the second electromagnetic sensor 22 relative to the second optical tracker 12 12,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 = T 0,12 * T 12,22 In this embodiment, the second electromagnetic sensor 22 is preferably attached to the distal region of the first instrument 31, and the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. The advantages of arranging the two electromagnetic sensors in this way will be described below.

[0144] The second method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the first optical tracker 11 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 (or to the head of a patient with a determined position relationship with the first optical tracker 11) in advance at a determined position relationship, and the position T of the coordinate system of the first optical tracker 11 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position of the second electromagnetic sensor 22 in the optical coordinate system by the processing control device 42. 0,11 The position T of the coordinate system of the second electromagnetic sensor 22 relative to the coordinate system of the first optical tracker 11 11,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 =T 0,11 * T 11,22 In this embodiment, specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 , and the first electromagnetic sensor 21 is attached to the proximal region of the second instrument 32 , in the hope of being as close to the first electromagnetic sensor 21 as possible.

[0145] S52′: taking the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the second electromagnetic sensor 22 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the second electromagnetic sensor 22.

[0146] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the second electromagnetic sensor 22 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,22 The position T' of the coordinate system of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation 0,22 = T 0,23 * T' 23,22 , and use this posture as the posture to be calibrated for the second electromagnetic sensor 22.

[0147] S53 ′: taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the first electromagnetic sensor 21 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the first electromagnetic sensor 21 .

[0148] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13 The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,21 The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,23 * T' 23,21 , and use this posture as the posture to be calibrated of the first electromagnetic sensor 21.

[0149] S54 ′: obtaining a calibration matrix based on the to-be-calibrated posture of the second electromagnetic sensor 22 and the reference posture, and calibrating the to-be-calibrated posture of the first electromagnetic sensor 21 using the calibration matrix.

[0150] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the second electromagnetic sensor 22 into a reference position T in the optical coordinate system. 0,22 The coordinate system of the second electromagnetic sensor 22 to be calibrated in the optical coordinate system is T' 0,22 The calibration matrix T'' is obtained by calculation 22,22 = T 0,22 * (-T' 0,22 ), then, the calibration matrix T'' 22,22 The real-time calculation T' is performed on the position of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system obtained in real time. 0,21 =T' 0,21 *T'' 22,22 , thereby calibrating the position and posture of the first electromagnetic sensor 21 and the second device 32 in real time.

[0151] The principle of calibrating the posture of the first electromagnetic sensor 21 in this method can be summarized as follows: the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based only on the optical positioning tracking principle and the determined posture relationship is calculated with the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained with the participation of the electromagnetic tracking positioning principle to obtain a calibration matrix, and then the calibration matrix is ​​used to calibrate the posture of the first electromagnetic sensor 21. More generally speaking: the posture deviation of the second electromagnetic sensor 22 between the two posture acquisition methods is used as the calibration matrix 2 to calibrate the posture of the first electromagnetic sensor 21.

[0152] In the second calibration method, the first method is superior to the second method, and the reason is that in the first method, the two electromagnetic sensors can be arranged in the distal area of ​​the two instruments. In this way, the positions of the two electromagnetic sensors are close, and the two electromagnetic sensors are basically (or, with a high probability) in the magnetic field area with the same distortion. Therefore, the posture deviation of the second electromagnetic sensor 22 is highly consistent with the posture deviation of the first electromagnetic sensor 21. Therefore, the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 has a high accuracy in calibrating the posture of the first electromagnetic sensor 21. However, in the second method, since the second electromagnetic sensor 22 is arranged on the first optical tracker 11 (or, the patient's head), the positions of the first electromagnetic sensor 21 and the second electromagnetic sensor 22 located on the second instrument 32 are far apart, which results in that the distortion of the magnetic field areas where the first electromagnetic sensor 21 and the second electromagnetic sensor 22 are located may be different, which may cause the calibration accuracy of the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 for the first electromagnetic sensor 21 to be lower than that of the first method.

[0153] In the second method, the second electromagnetic sensor 22 can be configured in the WeChat gimbal, and the micro-driving component (such as a micro-motor) in the WeChat gimbal drives the second electromagnetic sensor 22 to adjust its posture, so that the posture of the second electromagnetic sensor 22 is consistent with the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 in real time in the optical coordinate system, and thus the first electromagnetic sensor 21 is calibrated based on the calibration matrix obtained by the second electromagnetic sensor 22, which is conducive to reducing the reduction in calibration accuracy caused by the excessive spatial angle of the two electromagnetic sensors. S50: Calibrate the posture of the first electromagnetic sensor 21.

[0154] like Figures 8 to 11 Combined with Figure 7 As shown, when obtaining the position T' of the first electromagnetic sensor 21 in the optical coordinate system 0,21 In the process, due to the existence of the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle to obtain the first electromagnetic sensor 21 relative to the magnetic field generator 23 posture T' 23,21 Although the present invention reduces or minimizes magnetic field distortion and posture deviation caused by magnetic field distortion by configuring a homogeneous operating table 50 and arranging the magnetic field generator 23 on the front side of the operating table 50 near the head, the magnetic field distortion cannot be completely eliminated, resulting in deviation in the posture obtained based on the electromagnetic positioning tracking principle. Therefore, in the process of navigating the first instrument 31 and the second instrument 32, the posture T' of the coordinate system of the first electromagnetic sensor 21 on the second instrument 32 in the optical coordinate system can be 0,21 Perform calibration. The calibration method can be summarized as follows: Get the calibration matrix T'' 21,21 , using the processing control device 42 to change the coordinate system of the first electromagnetic sensor 21 to the position T' in the optical coordinate system 0,21 With the calibration matrix T' 0,21 The calibrated pose T' is obtained by calculation 0,21 *T'' 21,21 , the position T' of the coordinate system of the calibrated first electromagnetic sensor 21 in the optical coordinate system 0,21 *T'' 21,21 Compared with the pose T' before calibration 0,21 More accurate, thereby improving the navigation accuracy of the second instrument 32. Two specific methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0155] S60: Based on the posture of the second optical tracker 12 in the optical coordinate system and the posture relationship between the second optical tracker 12 and the first instrument 31, the posture of the first instrument 31 in the optical coordinate system is obtained; based on the calibrated posture of the first electromagnetic sensor 21 in the optical coordinate system and the posture relationship between the first electromagnetic sensor 21 and the second instrument 32, the calibrated posture of the second instrument 32 in the optical coordinate system is obtained; based on the obtained postures, the first instrument 31 and the second instrument 32 are navigated and visualized in the anatomical image.

[0156] Specifically, the acquired coordinate system of the second optical tracker 12 is converted into the position T of the optical coordinate system by using the processing control device 42. 0,12 The position T of the coordinate system of the first instrument 31 relative to the coordinate system of the second optical tracker 12 stored in the processing control device 42 12,31 The position T of the coordinate system of the first device 31 in the optical coordinate system is obtained by calculation. 0,31 =T 0,12 *T 12,31 ; The calibrated first electromagnetic sensor 21 coordinate system in the optical coordinate system posture T ' 0,21 *T'' 21,21 The position T of the coordinate system of the second device 32 relative to the coordinate system of the first electromagnetic sensor 21 stored in the processing control device 42 21,32 The position T′ of the coordinate system of the calibrated first instrument 31 in the optical coordinate system is obtained by calculation. 0,21 *T'' 21,21 *T 21,32 .

[0157] In the display device 41, based on the obtained postures of the first instrument 31 and the second instrument 32, navigation is performed on the first instrument 31 and the second instrument 32, and the first instrument 31 and the second instrument 32 unified in the optical coordinate system are displayed in an anatomical image describing the anatomical structure of the head to achieve visualization of the first instrument 31 and the second instrument 32 in the anatomical image.

[0158] Two methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0159] like Figure 8 and Fig. 9 As shown, a first method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0160] Before implementing this method, the first device 31 and the second device 32 need to be configured into the following mechanical matching mode: The first instrument 31 and the second instrument 32 can be rigidly and detachably attached, and in the attached state, the first instrument 31 and the second instrument 32 have a certain posture relationship.

[0161] In order to achieve the above-mentioned cooperation mode, the first device 31 and the second device 32 are additionally provided with the following structures: A first positioning structure is configured on the first instrument 31, and a second positioning structure is configured on the second instrument 32. The first instrument 31 and the second instrument 32 can be detachably attached via the first positioning structure and the second positioning structure. Specifically, two first positioning rings each having a positioning recess are fixedly sleeved on the outer circumference of the proximal region of the first instrument 31, and two first positioning rings each having a positioning protrusion are fixedly sleeved on the outer circumference of the proximal region of the second instrument 32. The two positioning protrusions are correspondingly inserted into the two positioning recesses, so that the first instrument 31 and the second instrument 32 are attached in a rigid, detachable manner with a certain posture relationship, and data on the posture relationship between the first instrument 31 and the second instrument 32 are stored in the processing and control device 42.

[0162] like Figure 8 and Fig. 9 As shown, the first method provided by the present invention for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system includes the following steps: S51: Obtaining the posture of the first electromagnetic sensor 21 relative to the second optical tracker 12 based on the posture relationship between the first device 31 and the second device 32 in the attached state.

[0163] Specifically, at least before the distal ends of the first instrument 31 and the second instrument 32 enter the skull through the cranial entrance, the first instrument 31 and the second instrument 32 are attached once. In the attached state, due to the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second instrument 32, 32,21 , the position T of the coordinate system of the second instrument 32 relative to the coordinate system of the first instrument 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 is known and pre-stored in the processing control device 42. Therefore, the processing control device 42 is used to convert the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 into 32,21 , the position T of the coordinate system of the second instrument 32 relative to the coordinate system of the first instrument 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 can be obtained by calculation. 12,21 =T32,21 *T 31,32 *T 12,31 .

[0164] Preferably, if Fig. 9 As shown, the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. For example, the first electromagnetic sensor 21 is attached to the inner side of the tube wall in the distal region. If the first electromagnetic sensor 21 can be arranged in the distal region of the second instrument 32, then after the distal transcranial entrance of the first instrument 31 and the second instrument 32 reaches the intracranial lesion and before the lesion is treated, the first instrument 31 and the second instrument 32 can be attached again. The advantage of attaching the first instrument 31 and the second instrument 32 again at this stage will be explained below.

[0165] S52: Taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the first electromagnetic sensor 21 in the attached state relative to the second optical tracker 12 and the posture of the second optical tracker 12 in the optical coordinate system acquired by the optical navigation device 10 as the reference posture.

[0166] Specifically, in the attached state, the obtained position and posture T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 is calculated by the processing control device 42. 12,21 The position T of the coordinate system of the second optical tracker 12 obtained by the optical navigation device in the optical coordinate system 0,12 The position T of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation. 0,21 = T 12,21 * T 0,12 , the pose T 0,21 as the reference pose.

[0167] It should be noted that this step and the reference posture described below are all obtained by calculating the posture obtained by the optical navigation device 10 based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship between related instruments or equipment. The reason for using the posture obtained by calculating the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship as the reference posture is that the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship are more accurate than the posture obtained by the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle. Therefore, the reference posture is used as the reference for calibrating the posture.

[0168] S53: The posture of the third optical tracker 13 in the optical coordinate system obtained by the optical navigation device 10 in the attached state, the posture relationship between the magnetic field generator 23 and the third optical tracker 13, and the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained by the electromagnetic navigation device 20 relative to the magnetic field generator 23 are taken as the posture to be calibrated.

[0169] Specifically, in the attached state, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into a position T in the optical coordinate system. 0,13 , the position T of the coordinate system of the magnetic field generator 23 stored in the processing device relative to the coordinate system of the third optical tracker 13 13,23 , the position T′ of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 obtained by the electromagnetic navigation device 20 23,21 The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,13 * T 13,23 * T' 23,21 , since the position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system 0,21 There is a method to obtain the position T' based on the electromagnetic positioning tracking principle 23,21 In the link, due to the distortion of the magnetic field, the posture obtained based on the electromagnetic positioning tracking principle has deviations, so the posture T' 0,21 As the posture to be calibrated.

[0170] S54: obtaining a calibration matrix based on the to-be-calibrated posture of the first electromagnetic sensor 21 and the reference posture, and calibrating the posture of the first electromagnetic sensor 21 in the optical coordinate system using the calibration matrix.

[0171] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the first electromagnetic sensor 21 into a reference position T in the optical coordinate system. 0,21 The coordinate system of the first electromagnetic sensor 21 to be calibrated in the optical coordinate system is T' 0,21 The calibration matrix T'' is obtained by calculation 21,21 = T 0,21 * (- T' 0,21 ), then, the calibration matrix T'' 21,21 The position and posture of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system are calculated in real time, so that the position and posture of the first electromagnetic sensor 21 and the second device 32 are calibrated in real time.

[0172] In fact, the calibration matrix obtained by the above method characterizes and quantifies the difference between the distorted magnetic field and the preset magnetic field to a certain extent. For example, the calibration matrix characterizes and quantifies the difference in density of magnetic flux lines before and after local distortion or the overall offset of magnetic flux lines before and after magnetic field offset to a certain extent. Therefore, the process of posture calibration is also the process of correcting magnetic field distortion. In this way, when the second instrument 32 cooperates with the first instrument 31 to perform a treatment operation on the lesion, by using the calibration matrix T'' 21,21 The first electromagnetic sensor 21 and the second device 32 are calibrated to improve the accuracy of navigation of the second device 32 to a certain extent.

[0173] The advantage of the above-mentioned preference to attach the first electromagnetic sensor 21 to the distal region of the second instrument 32, and preferably to attach the first instrument 31 and the second instrument 32 again after the distal ends of the first instrument 31 and the second instrument 32 reach the intracranial lesion through the cranial entrance and before treating the lesion to obtain the calibration matrix of the magnetic field region where the first electromagnetic sensor 21 is located (the region where the lesion is located) is that, in fact, when treating the lesion, accurate positioning and tracking of the distal ends of the two operating instruments is the key to accurately treating the lesion. If the first electromagnetic sensor 21 is arranged at the proximal end of the second instrument 32, because the two intracranial operating instruments are rod-shaped instruments, the distance between the first electromagnetic sensor 21 and the distal end is relatively large, and because the second instrument 32 inevitably depends on the calibration after calibration. However, there is a posture deviation (the posture deviation of the instrument calibrated by the calibration matrix is ​​reduced and difficult to completely eliminate), therefore, the posture deviation of the second instrument 32 after calibration will increase after being converted to the distal end, and if the first electromagnetic sensor 21 is arranged near the distal end of the second instrument 32, the position deviation will not change much after conversion to the end; the reason for calibrating the second instrument 32 again after reaching the lesion is that the magnetic field distortion in the lesion area may be different from that in its peripheral area (such as the extracranial area), and the calibration matrix obtained may be different. Using the calibration matrix obtained near the lesion area to calibrate the first instrument 31 for the treatment operation is beneficial to reducing the posture deviation of the first instrument 31 during the treatment operation.

[0174] A second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0175] Before implementing this method, a second electromagnetic sensor 22 for acquiring posture based on the electromagnetic positioning tracking principle is arranged on the first instrument 31 or in an area having a certain posture relationship with the first optical tracker 11 (e.g., directly on the first optical tracker 11 or on the patient's head).

[0176] like Fig.10 and Fig.11As shown, the second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system provided by the present invention includes the following steps: S51 ′: taking the position and posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the position and posture of the first optical tracker 11 or the second optical tracker 12 in the optical coordinate system as a reference position and posture of the second electromagnetic sensor 22 .

[0177] In this step, the reference position of the second electromagnetic sensor 22 in the optical coordinate system can be obtained in two ways.

[0178] The first method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the second optical tracker 12 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first device 31 in advance with a determined position relationship, and the position of the coordinate system of the second optical tracker 12 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position T by the processing control device 42. 0,12 The position T of the second electromagnetic sensor 22 relative to the second optical tracker 12 12,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 = T 0,12 * T 12,22 In this embodiment, the second electromagnetic sensor 22 is preferably attached to the distal region of the first instrument 31, and the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. The advantages of arranging the two electromagnetic sensors in this way will be described below.

[0179] The second method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the first optical tracker 11 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 (or to the head of a patient with a determined position relationship with the first optical tracker 11) in advance at a determined position relationship, and the position T of the coordinate system of the first optical tracker 11 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position of the second electromagnetic sensor 22 in the optical coordinate system by the processing control device 42. 0,11 The position T of the coordinate system of the second electromagnetic sensor 22 relative to the coordinate system of the first optical tracker 11 11,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 =T 0,11 * T 11,22 In this embodiment, specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 , and the first electromagnetic sensor 21 is attached to the proximal region of the second instrument 32 , in the hope of being as close to the first electromagnetic sensor 21 as possible.

[0180] S52′: taking the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the second electromagnetic sensor 22 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the second electromagnetic sensor 22.

[0181] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13 The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the second electromagnetic sensor 22 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,22 The position T' of the coordinate system of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation 0,22 = T 0,23 * T' 23,22 , and use this posture as the posture to be calibrated for the second electromagnetic sensor 22.

[0182] S53 ′: taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the first electromagnetic sensor 21 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the first electromagnetic sensor 21 .

[0183] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13 The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,21The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,23 * T' 23,21 , and use this posture as the posture to be calibrated of the first electromagnetic sensor 21.

[0184] S54 ′: obtaining a calibration matrix based on the to-be-calibrated posture of the second electromagnetic sensor 22 and the reference posture, and calibrating the to-be-calibrated posture of the first electromagnetic sensor 21 using the calibration matrix.

[0185] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the second electromagnetic sensor 22 into a reference position T in the optical coordinate system. 0,22 The coordinate system of the second electromagnetic sensor 22 to be calibrated in the optical coordinate system is T' 0,22 The calibration matrix T'' is obtained by calculation 22,22 = T 0,22 * (-T' 0,22 ), then, the calibration matrix T'' 22,22 The real-time calculation T' is performed on the position of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system obtained in real time. 0,21 =T' 0,21 *T'' 22,22 , thereby calibrating the position and posture of the first electromagnetic sensor 21 and the second device 32 in real time.

[0186] The principle of calibrating the posture of the first electromagnetic sensor 21 in this method can be summarized as follows: the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based only on the optical positioning tracking principle and the determined posture relationship is calculated with the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained with the participation of the electromagnetic tracking positioning principle to obtain a calibration matrix, and then the calibration matrix is ​​used to calibrate the posture of the first electromagnetic sensor 21. More generally speaking: the posture deviation of the second electromagnetic sensor 22 between the two posture acquisition methods is used as the calibration matrix 2 to calibrate the posture of the first electromagnetic sensor 21.

[0187] In the second calibration method, the first method is superior to the second method, and the reason is that in the first method, the two electromagnetic sensors can be arranged in the distal area of ​​the two instruments. In this way, the positions of the two electromagnetic sensors are close, and the two electromagnetic sensors are basically (or, with a high probability) in the magnetic field area with the same distortion. Therefore, the posture deviation of the second electromagnetic sensor 22 is highly consistent with the posture deviation of the first electromagnetic sensor 21. Therefore, the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 has a high accuracy in calibrating the posture of the first electromagnetic sensor 21. However, in the second method, since the second electromagnetic sensor 22 is arranged on the first optical tracker 11 (or, the patient's head), the positions of the first electromagnetic sensor 21 and the second electromagnetic sensor 22 located on the second instrument 32 are far apart, which results in that the distortion of the magnetic field areas where the first electromagnetic sensor 21 and the second electromagnetic sensor 22 are located may be different, which may cause the calibration accuracy of the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 for the first electromagnetic sensor 21 to be lower than that of the first method.

[0188] In the second method, the second electromagnetic sensor 22 can be configured in the WeChat gimbal, and the micro-driving component (such as a micro-motor) in the WeChat gimbal drives the second electromagnetic sensor 22 to adjust its posture, so that the posture of the second electromagnetic sensor 22 is consistent with the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 in real time in the optical coordinate system, and thus the first electromagnetic sensor 21 is calibrated based on the calibration matrix obtained by the second electromagnetic sensor 22, which is conducive to reducing the reduction in calibration accuracy caused by the excessive spatial angle of the two electromagnetic sensors. S50: Calibrate the posture of the first electromagnetic sensor 21.

[0189] like Figures 8 to 11 Combined with Figure 7 As shown, when obtaining the position T' of the first electromagnetic sensor 21 in the optical coordinate system 0,21 In the process, due to the existence of the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle to obtain the first electromagnetic sensor 21 relative to the magnetic field generator 23 posture T' 23,21 Although the present invention reduces or minimizes magnetic field distortion and posture deviation caused by magnetic field distortion by configuring a homogeneous operating table 50 and arranging the magnetic field generator 23 on the front side of the operating table 50 near the head, the magnetic field distortion cannot be completely eliminated, resulting in deviation in the posture obtained based on the electromagnetic positioning tracking principle. Therefore, in the process of navigating the first instrument 31 and the second instrument 32, the posture T' of the coordinate system of the first electromagnetic sensor 21 on the second instrument 32 in the optical coordinate system can be 0,21 Perform calibration. The calibration method can be summarized as follows: Get the calibration matrix T'' 21,21, using the processing control device 42 to change the coordinate system of the first electromagnetic sensor 21 to the position T' in the optical coordinate system 0,21 With the calibration matrix T' 0,21 The calibrated pose T' is obtained by calculation 0,21 *T'' 21,21 , the position T' of the coordinate system of the calibrated first electromagnetic sensor 21 in the optical coordinate system 0,21 *T'' 21,21 Compared with the pose T' before calibration 0,21 More accurate, thereby improving the navigation accuracy of the second instrument 32. Two specific methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0190] S60: Based on the posture of the second optical tracker 12 in the optical coordinate system and the posture relationship between the second optical tracker 12 and the first instrument 31, the posture of the first instrument 31 in the optical coordinate system is obtained; based on the calibrated posture of the first electromagnetic sensor 21 in the optical coordinate system and the posture relationship between the first electromagnetic sensor 21 and the second instrument 32, the calibrated posture of the second instrument 32 in the optical coordinate system is obtained; based on the obtained postures, the first instrument 31 and the second instrument 32 are navigated and visualized in the anatomical image.

[0191] Specifically, the acquired coordinate system of the second optical tracker 12 is converted into the position T of the optical coordinate system by using the processing control device 42. 0,12 The position T of the coordinate system of the first instrument 31 relative to the coordinate system of the second optical tracker 12 stored in the processing control device 42 12,31 The position T of the coordinate system of the first device 31 in the optical coordinate system is obtained by calculation. 0,31 =T 0,12 *T 12,31 ; The calibrated first electromagnetic sensor 21 coordinate system in the optical coordinate system posture T ' 0,21 *T'' 21,21 The position T of the coordinate system of the second device 32 relative to the coordinate system of the first electromagnetic sensor 21 stored in the processing control device 42 21,32 The position T′ of the coordinate system of the calibrated first instrument 31 in the optical coordinate system is obtained by calculation. 0,21 *T'' 21,21 *T 21,32 .

[0192] In the display device 41, based on the obtained postures of the first instrument 31 and the second instrument 32, navigation is performed on the first instrument 31 and the second instrument 32, and the first instrument 31 and the second instrument 32 unified in the optical coordinate system are displayed in an anatomical image describing the anatomical structure of the head to achieve visualization of the first instrument 31 and the second instrument 32 in the anatomical image.

[0193] Two methods for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system are provided below.

[0194] like Figure 8 and Fig. 9 As shown, a first method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0195] Before implementing this method, the first device 31 and the second device 32 need to be configured into the following mechanical matching mode: The first instrument 31 and the second instrument 32 can be rigidly and detachably attached, and in the attached state, the first instrument 31 and the second instrument 32 have a certain posture relationship.

[0196] In order to achieve the above-mentioned cooperation mode, the first device 31 and the second device 32 are additionally provided with the following structures: A first positioning structure is configured on the first instrument 31, and a second positioning structure is configured on the second instrument 32. The first instrument 31 and the second instrument 32 can be detachably attached via the first positioning structure and the second positioning structure. Specifically, two first positioning rings each having a positioning recess are fixedly sleeved on the outer circumference of the proximal region of the first instrument 31, and two first positioning rings each having a positioning protrusion are fixedly sleeved on the outer circumference of the proximal region of the second instrument 32. The two positioning protrusions are correspondingly inserted into the two positioning recesses, so that the first instrument 31 and the second instrument 32 are attached in a rigid, detachable manner with a certain posture relationship, and data on the posture relationship between the first instrument 31 and the second instrument 32 are stored in the processing and control device 42.

[0197] like Figure 8 and Fig. 9 As shown, the first method provided by the present invention for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system includes the following steps: S51: Obtaining the posture of the first electromagnetic sensor 21 relative to the second optical tracker 12 based on the posture relationship between the first device 31 and the second device 32 in the attached state.

[0198] Specifically, at least before the distal ends of the first instrument 31 and the second instrument 32 enter the skull through the cranial entrance, the first instrument 31 and the second instrument 32 are attached once. In the attached state, due to the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second instrument 32, 32,21 , the position T of the coordinate system of the second device 32 relative to the coordinate system of the first device 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 is known and pre-stored in the processing control device 42. Therefore, the processing control device 42 is used to convert the position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second device 32 into 32,21 , the position T of the coordinate system of the second device 32 relative to the coordinate system of the first device 31 31,32 , the position T of the coordinate system of the first device 31 relative to the coordinate system of the second optical tracker 12 12,31 The position T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 can be obtained by calculation. 12,21 =T 32,21 *T 31,32 *T 12,31 .

[0199] Preferably, if Fig. 9 As shown, the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. For example, the first electromagnetic sensor 21 is attached to the inner side of the tube wall in the distal region. If the first electromagnetic sensor 21 can be arranged in the distal region of the second instrument 32, then after the distal transcranial entrance of the first instrument 31 and the second instrument 32 reaches the intracranial lesion and before the lesion is treated, the first instrument 31 and the second instrument 32 can be attached again. The advantage of attaching the first instrument 31 and the second instrument 32 again at this stage will be explained below.

[0200] S52: Taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the first electromagnetic sensor 21 in the attached state relative to the second optical tracker 12 and the posture of the second optical tracker 12 in the optical coordinate system acquired by the optical navigation device 10 as the reference posture.

[0201] Specifically, in the attached state, the obtained position and posture T of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the second optical tracker 12 is calculated by the processing control device 42. 12,21 The position T of the coordinate system of the second optical tracker 12 obtained by the optical navigation device in the optical coordinate system 0,12 The position T of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation. 0,21= T 12,21 * T 0,12 , the pose T 0,21 as the reference pose.

[0202] It should be noted that this step and the reference posture described below are all obtained by calculating the posture obtained by the optical navigation device 10 based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship between related instruments or equipment. The reason for using the posture obtained by calculating the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship as the reference posture is that the posture obtained based on the optical positioning tracking principle and the posture obtained based on the determined posture relationship are more accurate than the posture obtained by the electromagnetic navigation device 20 based on the electromagnetic positioning tracking principle. Therefore, the reference posture is used as the reference for calibrating the posture.

[0203] S53: The posture of the third optical tracker 13 in the optical coordinate system obtained by the optical navigation device 10 in the attached state, the posture relationship between the magnetic field generator 23 and the third optical tracker 13, and the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained by the electromagnetic navigation device 20 relative to the magnetic field generator 23 are taken as the posture to be calibrated.

[0204] Specifically, in the attached state, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into a position T in the optical coordinate system. 0,13 , the position T of the coordinate system of the magnetic field generator 23 stored in the processing device relative to the coordinate system of the third optical tracker 13 13,23 , the position T′ of the coordinate system of the first electromagnetic sensor 21 relative to the coordinate system of the magnetic field generator 23 obtained by the electromagnetic navigation device 20 23,21 The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,13 * T 13,23 * T' 23,21 , since the position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system 0,21 There is a method to obtain the position T' based on the electromagnetic positioning tracking principle 23,21 In the link, due to the distortion of the magnetic field, the posture obtained based on the electromagnetic positioning tracking principle has deviations, so the posture T' 0,21 As the posture to be calibrated.

[0205] S54: obtaining a calibration matrix based on the to-be-calibrated posture of the first electromagnetic sensor 21 and the reference posture, and calibrating the posture of the first electromagnetic sensor 21 in the optical coordinate system using the calibration matrix.

[0206] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the first electromagnetic sensor 21 into a reference position T in the optical coordinate system. 0,21 The coordinate system of the first electromagnetic sensor 21 to be calibrated in the optical coordinate system is T' 0,21 The calibration matrix T'' is obtained by calculation 21,21 = T 0,21 * (- T' 0,21 ), then, the calibration matrix T'' 21,21 The position and posture of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system are calculated in real time, so that the position and posture of the first electromagnetic sensor 21 and the second device 32 are calibrated in real time.

[0207] In fact, the calibration matrix obtained by the above method characterizes and quantifies the difference between the distorted magnetic field and the preset magnetic field to a certain extent. For example, the calibration matrix characterizes and quantifies the difference in density of magnetic flux lines before and after local distortion or the overall offset of magnetic flux lines before and after magnetic field offset to a certain extent. Therefore, the process of posture calibration is also the process of correcting magnetic field distortion. In this way, when the second instrument 32 cooperates with the first instrument 31 to perform a treatment operation on the lesion, by using the calibration matrix T'' 21,21 The first electromagnetic sensor 21 and the second device 32 are calibrated to improve the accuracy of navigation of the second device 32 to a certain extent.

[0208] The advantage of the above-mentioned preference to attach the first electromagnetic sensor 21 to the distal region of the second instrument 32, and preferably to attach the first instrument 31 and the second instrument 32 again after the distal ends of the first instrument 31 and the second instrument 32 reach the intracranial lesion through the cranial entrance and before treating the lesion to obtain the calibration matrix of the magnetic field region where the first electromagnetic sensor 21 is located (the region where the lesion is located) is that, in fact, when treating the lesion, accurate positioning and tracking of the distal ends of the two operating instruments is the key to accurately treating the lesion. If the first electromagnetic sensor 21 is arranged at the proximal end of the second instrument 32, because the two intracranial operating instruments are rod-shaped instruments, the distance between the first electromagnetic sensor 21 and the distal end is relatively large, and because the second instrument 32 inevitably depends on the calibration after calibration. However, there is a posture deviation (the posture deviation of the instrument calibrated by the calibration matrix is ​​reduced and difficult to completely eliminate), therefore, the posture deviation of the second instrument 32 after calibration will increase after being converted to the distal end, and if the first electromagnetic sensor 21 is arranged near the distal end of the second instrument 32, the position deviation will not change much after conversion to the end; the reason for calibrating the second instrument 32 again after reaching the lesion is that the magnetic field distortion in the lesion area may be different from that in its peripheral area (such as the extracranial area), and the calibration matrix obtained may be different. Using the calibration matrix obtained near the lesion area to calibrate the first instrument 31 for the treatment operation is beneficial to reducing the posture deviation of the first instrument 31 during the treatment operation.

[0209] A second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system.

[0210] Before implementing this method, a second electromagnetic sensor 22 for acquiring posture based on the electromagnetic positioning tracking principle is arranged on the first instrument 31 or in an area having a certain posture relationship with the first optical tracker 11 (e.g., directly on the first optical tracker 11 or on the patient's head).

[0211] like Fig.10 and Fig.11 As shown, the second method for calibrating the position and posture of the first electromagnetic sensor 21 in the optical coordinate system provided by the present invention includes the following steps: S51 ′: taking the position and posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the position and posture of the first optical tracker 11 or the second optical tracker 12 in the optical coordinate system as a reference position and posture of the second electromagnetic sensor 22 .

[0212] In this step, the reference position of the second electromagnetic sensor 22 in the optical coordinate system can be obtained in two ways.

[0213] The first method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the second optical tracker 12 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first device 31 in advance with a determined position relationship, and the position of the coordinate system of the second optical tracker 12 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position T by the processing control device 42. 0,12 The position T of the second electromagnetic sensor 22 relative to the second optical tracker 12 12,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 = T 0,12 * T 12,22 In this embodiment, the second electromagnetic sensor 22 is preferably attached to the distal region of the first instrument 31, and the first electromagnetic sensor 21 is attached to the distal region of the second instrument 32. The advantages of arranging the two electromagnetic sensors in this way will be described below.

[0214] The second method is to obtain the reference position of the second electromagnetic sensor 22 in the optical coordinate system based on the position of the first optical tracker 11 in the optical coordinate system. Specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 (or to the head of a patient with a determined position relationship with the first optical tracker 11) in advance at a determined position relationship, and the position T of the coordinate system of the first optical tracker 11 in the optical coordinate system obtained by the optical navigation device 10 is converted into the reference position of the second electromagnetic sensor 22 in the optical coordinate system by the processing control device 42. 0,11 The position T of the coordinate system of the second electromagnetic sensor 22 relative to the coordinate system of the first optical tracker 11 11,22 The reference position T of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation. 0,22 =T 0,11 * T 11,22 In this embodiment, specifically, the second electromagnetic sensor 22 is attached to the first optical tracker 11 , and the first electromagnetic sensor 21 is attached to the proximal region of the second instrument 32 , in the hope of being as close to the first electromagnetic sensor 21 as possible.

[0215] S52′: taking the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the second electromagnetic sensor 22 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the second electromagnetic sensor 22.

[0216] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the second electromagnetic sensor 22 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,22 The position T' of the coordinate system of the second electromagnetic sensor 22 in the optical coordinate system is obtained by calculation 0,22 = T 0,23 * T' 23,22 , and use this posture as the posture to be calibrated for the second electromagnetic sensor 22.

[0217] S53 ′: taking the posture of the first electromagnetic sensor 21 in the optical coordinate system obtained based on the posture of the magnetic field generator 23 in the optical coordinate system and the posture of the first electromagnetic sensor 21 relative to the magnetic field generator 23 acquired by the electromagnetic navigation device 20 as the posture to be calibrated of the first electromagnetic sensor 21 .

[0218] Specifically, the processing control device 42 is used to convert the coordinate system of the third optical tracker 13 acquired by the optical navigation device 10 into the position T in the optical coordinate system. 0,13 The position T of the coordinate system of the magnetic field generator 23 relative to the coordinate system of the third optical tracker 13 13,23 The position T of the coordinate system of the magnetic field generator 23 in the optical coordinate system is obtained by calculation. 0,23 =T 0,13 * T 13,23 , the obtained coordinate system of the magnetic field generator 23 is converted into the position T of the optical coordinate system by using the processing control device 42 0,23 The position T′ of the coordinate system of the first electromagnetic sensor 21 obtained by the electromagnetic navigation device 20 relative to the coordinate system of the magnetic field generator 23 23,21 The position T' of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system is obtained by calculation 0,21 = T 0,23 * T' 23,21 , and use this posture as the posture to be calibrated of the first electromagnetic sensor 21.

[0219] S54 ′: obtaining a calibration matrix based on the to-be-calibrated posture of the second electromagnetic sensor 22 and the reference posture, and calibrating the to-be-calibrated posture of the first electromagnetic sensor 21 using the calibration matrix.

[0220] Specifically, the processing control device 42 is used to convert the obtained coordinate system of the second electromagnetic sensor 22 into a reference position T in the optical coordinate system. 0,22 The coordinate system of the second electromagnetic sensor 22 to be calibrated in the optical coordinate system is T' 0,22 The calibration matrix T'' is obtained by calculation 22,22 = T 0,22 * (-T' 0,22 ), then, the calibration matrix T'' 22,22 The real-time calculation T' is performed on the position of the coordinate system of the first electromagnetic sensor 21 in the optical coordinate system obtained in real time. 0,21 =T' 0,21 *T'' 22,22 , thereby calibrating the position and posture of the first electromagnetic sensor 21 and the second device 32 in real time.

[0221] The principle of calibrating the posture of the first electromagnetic sensor 21 in this method can be summarized as follows: the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained based only on the optical positioning tracking principle and the determined posture relationship is calculated with the posture of the second electromagnetic sensor 22 in the optical coordinate system obtained with the participation of the electromagnetic tracking positioning principle to obtain a calibration matrix, and then the calibration matrix is ​​used to calibrate the posture of the first electromagnetic sensor 21. More generally speaking: the posture deviation of the second electromagnetic sensor 22 between the two posture acquisition methods is used as the calibration matrix 2 to calibrate the posture of the first electromagnetic sensor 21.

[0222] In the second calibration method, the first method is superior to the second method, and the reason is that in the first method, the two electromagnetic sensors can be arranged in the distal area of ​​the two instruments. In this way, the positions of the two electromagnetic sensors are close, and the two electromagnetic sensors are basically (or, with a high probability) in the magnetic field area with the same distortion. Therefore, the posture deviation of the second electromagnetic sensor 22 is highly consistent with the posture deviation of the first electromagnetic sensor 21. Therefore, the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 has a high accuracy in calibrating the posture of the first electromagnetic sensor 21. However, in the second method, since the second electromagnetic sensor 22 is arranged on the first optical tracker 11 (or, the patient's head), the positions of the first electromagnetic sensor 21 and the second electromagnetic sensor 22 located on the second instrument 32 are far apart, which results in that the distortion of the magnetic field areas where the first electromagnetic sensor 21 and the second electromagnetic sensor 22 are located may be different, which may cause the calibration accuracy of the calibration matrix obtained based on the posture deviation of the second electromagnetic sensor 22 for the first electromagnetic sensor 21 to be lower than that of the first method.

[0223] In the second method, the second electromagnetic sensor 22 can be configured in the WeChat gimbal, and the micro-driving component (such as a micro-motor) in the WeChat gimbal drives the second electromagnetic sensor 22 to adjust its posture, so that the posture of the second electromagnetic sensor 22 is consistent with the first electromagnetic sensor 21 acquired by the electromagnetic navigation device 20 in real time in the optical coordinate system, and thereby the first electromagnetic sensor 21 is calibrated based on the calibration matrix obtained by the second electromagnetic sensor 22, which is conducive to reducing the reduction in calibration accuracy caused by the excessively large spatial angle of the two electromagnetic sensors.

Claims

1. A method for navigating two intracranial operating instruments, the two operating instruments comprising a first instrument and a second instrument, characterized in that: The first optical tracker is attached to the surgical site, the second optical tracker and the first electromagnetic sensor are attached to the first and second instruments respectively in a determined posture relationship, and the third optical tracker has a determined posture relationship with the magnetic field generator, and the method includes: obtaining anatomical images depicting the anatomy of the surgical site; Marking the target area, cranial entrance, and surgical path in the anatomical image; Acquire the position and posture of the first optical tracker in the optical coordinate system by using an optical navigation device, and register the anatomical image in the optical coordinate system based on the position and posture of the first optical tracker in the optical coordinate system and the position and posture of the anatomical image in the image coordinate system; The optical navigation device is used to obtain the positions and postures of the second and third optical trackers in the optical coordinate system, and the electromagnetic navigation device is used to obtain the position and posture of the first electromagnetic sensor relative to the magnetic field generator. The position and posture of the first electromagnetic sensor in the optical coordinate system is obtained based on the position and posture of the third optical tracker in the optical coordinate system, the position and posture relationship between the magnetic field generator and the third optical tracker, and the position and posture of the first electromagnetic sensor relative to the magnetic field generator. Calibrate the position and posture of the first electromagnetic sensor; Based on the posture relationship between the second optical tracker and the first instrument and the posture relationship between the first electromagnetic sensor and the second instrument, the posture of the first instrument in the optical coordinate system and the calibrated posture of the second instrument in the optical coordinate system are obtained, and the first instrument and the second instrument are visualized in the anatomical image.

2. The method according to claim 1, characterized in that: The first instrument and the second instrument can be attached in a rigid and detachable manner, and in the attached state, the first instrument and the second instrument have a certain posture relationship; The calibrating the position and posture of the first electromagnetic sensor includes: Obtaining a position and posture of the first electromagnetic sensor relative to the second optical tracker based on a position and posture relationship between the first device and the second device in an attached state; The position of the first electromagnetic sensor in the optical coordinate system obtained based on the position of the first electromagnetic sensor relative to the second optical tracker in the attached state and the position of the second optical tracker in the optical coordinate system acquired by the optical navigation device is used as a reference position; The pose of the first electromagnetic sensor in the optical coordinate system obtained based on the pose of the third optical tracker in the attached state obtained by the optical navigation device, the pose relationship between the magnetic field generator and the third optical tracker, and the pose of the first electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device is used as the pose to be calibrated; A calibration matrix is ​​obtained based on the to-be-calibrated posture and the reference posture of the first electromagnetic sensor, and the posture of the first electromagnetic sensor in the optical coordinate system is calibrated using the calibration matrix.

3. The method according to claim 1, characterized in that placing a second electromagnetic sensor at the surgical site or in the vicinity of the surgical site; The calibrating the position and posture of the first electromagnetic sensor includes: Using the position and posture of the second electromagnetic sensor in the optical coordinate system obtained based on the position and posture of the first optical tracker or the second optical tracker in the optical coordinate system as a reference position and posture of the second electromagnetic sensor; The posture of the second electromagnetic sensor in the optical coordinate system obtained based on the posture of the magnetic field generator in the optical coordinate system and the posture of the second electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device is used as the posture to be calibrated of the second electromagnetic sensor; The posture of the first electromagnetic sensor in the optical coordinate system obtained based on the posture of the magnetic field generator in the optical coordinate system and the posture of the first electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device is used as the posture to be calibrated of the first electromagnetic sensor; A calibration matrix is ​​obtained based on the to-be-calibrated posture of the second electromagnetic sensor and the reference posture, and the to-be-calibrated posture of the first electromagnetic sensor is calibrated using the calibration matrix.

4. The method according to claim 3, characterized in that The second electromagnetic sensor is attached to the distal region of the first instrument in a manner that forms a determined posture relationship with the second optical tracker, and the first electromagnetic sensor is attached to the distal region of the second instrument; Obtaining the reference position and posture of the second electromagnetic sensor in the optical coordinate system based on the position and posture of the second optical tracker in the optical coordinate system includes: The reference position and posture of the second electromagnetic sensor in the optical coordinate system is obtained based on the position and posture of the second optical tracker in the optical coordinate system acquired by the optical navigation device and the position and posture relationship between the second electromagnetic sensor and the second optical tracker.

5. The method according to claim 3, characterized in that: The second electromagnetic sensor has a determined posture relationship with the first optical tracker; Obtaining a reference position and posture of the second electromagnetic sensor in the optical coordinate system based on the position and posture of the first optical tracker in the optical coordinate system includes: The reference position and posture of the second electromagnetic sensor in the optical coordinate system is obtained based on the position and posture of the first optical tracker in the optical coordinate system acquired by the optical navigation device and the position and posture relationship between the second electromagnetic sensor and the first optical tracker.

6. A navigation system for performing surgical navigation on two intracranial operating instruments, the two operating instruments comprising a first instrument and a second instrument, characterized in that: The navigation system includes an image acquisition device, a navigation apparatus and a computer device; The navigation apparatus includes an optical navigation device, first, second and third optical trackers, an electromagnetic navigation device and a first electromagnetic sensor; Computer equipment includes processing control equipment and display equipment; The first optical tracker is attached to the surgical site, the second optical tracker and the first electromagnetic sensor are attached to the first and second instruments respectively in a determined posture relationship, and the third optical tracker is attached to the periphery of the surgical site and has a determined posture relationship with the magnetic field generator; The image acquisition device is used to acquire original images describing the anatomical structure of the surgical site; The optical navigation device is used to obtain the positions and postures of the first, second and third optical trackers in the optical coordinate system; The electromagnetic navigation device is used to obtain the position and posture of the first electromagnetic sensor relative to the magnetic field generator; Process control equipment is used to: Processing the image to be processed into an anatomical image; registering the anatomical image in the optical coordinate system based on the pose of the first optical tracker in the optical coordinate system and the pose of the first optical tracker in the image coordinate system of the anatomical image; Calculating the position and posture of the first device in the optical coordinate system based on the position and posture of the second optical tracker in the optical coordinate system and the position and posture relationship between the second optical tracker and the first device; and calculating the position and posture of the second device in the optical coordinate system based on the position and posture of the third optical tracker in the optical coordinate system, the position and posture relationship between the magnetic field generator and the third optical tracker, the position and posture of the first electromagnetic sensor relative to the magnetic field generator, and the position and posture relationship with the second device; Calibrate the position and posture of the first electromagnetic sensor; The display device is used to visualize the first and second instruments in the anatomical image.

7. The navigation system according to claim 6, characterized in that: The first device has a first positioning structure, the second device has a second positioning structure, the first device and the second device can be detachably attached via the first positioning structure and the second positioning structure, and in the attached state, the first device and the second device have a certain posture relationship; The processing control device is used to: The posture of the first electromagnetic sensor relative to the second optical tracker is calculated based on the posture relationship between the first device and the second device in the attached state; the posture of the first electromagnetic sensor in the optical coordinate system is calculated based on the posture of the first electromagnetic sensor relative to the second optical tracker in the attached state and the posture of the second optical tracker in the optical coordinate system and used as the reference posture; The pose of the first electromagnetic sensor in the optical coordinate system is calculated based on the pose of the third optical tracker in the attached state in the optical coordinate system, the pose relationship between the magnetic field generator and the third optical tracker, and the pose of the first electromagnetic sensor relative to the magnetic field generator and is used as the pose to be calibrated; A calibration matrix is ​​calculated based on the to-be-calibrated posture and the reference posture of the first electromagnetic sensor, and the posture of the first electromagnetic sensor in the optical coordinate system is calibrated using the calibration matrix.

8. The navigation system according to claim 6, characterized in that: The navigation device further includes a second electromagnetic sensor, which is arranged at the surgical site or in the vicinity of the surgical site; The processing control device is used to: Based on the pose of the first optical tracker or the second optical tracker in the optical coordinate system obtained by the optical navigation device, the pose of the second electromagnetic sensor in the optical coordinate system is calculated and used as the reference pose; based on the pose of the magnetic field generator in the optical coordinate system and the pose of the second electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device, the pose of the second electromagnetic sensor in the optical coordinate system is calculated and used as the pose to be calibrated; based on the pose of the magnetic field generator in the optical coordinate system and the pose of the first electromagnetic sensor relative to the magnetic field generator obtained by the electromagnetic navigation device, the pose of the first electromagnetic sensor in the optical coordinate system is calculated and used as the pose to be calibrated; A calibration matrix is ​​calculated based on the to-be-calibrated posture of the second electromagnetic sensor and the reference posture, and the to-be-calibrated posture of the first electromagnetic sensor is calibrated using the calibration matrix.

9. The navigation system according to claim 8, characterized in that: The first electromagnetic sensor is arranged in a distal region of the second instrument and the second electromagnetic sensor is arranged in a distal region of the first instrument.

10. The navigation system according to claim 8, characterized in that: The first electromagnetic sensor is arranged at a proximal region of the second instrument and the second electromagnetic sensor is arranged on the first optical tracker.

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