CN110547870B - Accurate liver operation navigation positioning device - Google Patents

Abstract

The invention provides a precise liver operation navigation positioning device which mainly comprises a diaphragm surface navigation module, a dirty surface navigation module and a focus navigation module, wherein the generated modules are used for marking each section of the liver surface and focus boundary lines. The operation navigation positioning module provides visual and clear liver surface dividing lines for liver surgeons, so that the anatomical excision of specific liver segments can be performed, the operation complications are reduced, and the prognosis of the operation excision of a liver tumor patient is improved. The invention integrates the advantages of a plurality of subjects and aims to solve the difficult problem of accurate liver segment excision operation. Through the construction of the digital three-dimensional liver, the intelligent segmentation of the liver, the acquisition of the surface boundary and the three-dimensional projection of the focus, and the design and the manufacture of the navigation and positioning module of the focus of the liver, the doctor can simply and easily recognize the surface boundary of the liver to be resected.

Description

A precise liver surgery navigation and positioning device

Technical Field

The present invention belongs to the field of medical devices and relates to a precise liver surgery navigation and positioning device. Through the surgical navigation and positioning module, the demarcation lines of liver segments and lesions can be accurately marked during liver surgery, thereby achieving precise liver surgery.

Background technique

As a complex surgical technique, liver surgery requires the surgeon to have a very deep and detailed understanding of the anatomy and pathological characteristics of the liver. At present, among the treatment methods for liver cancer, surgery is the only possible treatment method to cure liver cancer, and precise liver segment resection has more advantages than local tumor resection. The advantages of precise liver segment resection are: significantly reducing the recurrence rate of liver cancer after surgery, and at the same time improving the survival rate of patients after liver cancer surgery. However, previous attempts at precise liver segment resection have not achieved significant results and breakthroughs due to the limitations of the technology at the time. Recently, although some people have used CT personalized scanning and reconstruction to generate virtual liver images, and applied 3D printing technology to reproduce the structure of the liver and plan liver surgery. However, this method currently does not solve the problem of real-time navigation and precise liver segment resection during surgery. In order to solve the above problems, it is necessary to develop a new liver surgery navigation system (device).

Summary of the invention

The purpose of the present invention is to provide a precise liver surgery navigation and positioning device, which is composed of three modules: a diaphragmatic surface navigation module 1, a visceral surface navigation module 2 and a lesion navigation module 3.

A diaphragm surface sealing strip 1-1 is arranged around the diaphragm surface navigation module 1, the middle of the diaphragm surface navigation module 1 is hollowed out and provided with a navigation module inner sealing strip 1-2, and a diaphragm surface navigation module groove 1-3 and a circular hole 1-4 are arranged on the surface of the diaphragm surface navigation module 1.

A dirty surface sealing strip 2-1 is arranged around the dirty surface navigation module 2, a dirty surface navigation module groove 2-2 is arranged on the surface of the dirty surface navigation module 2, and a circular hole (not shown in the figure) which is the same as that of the diaphragm surface navigation module 1 is also arranged.

A lesion sealing strip 3-1 is arranged around the lesion navigation module 3, wherein a plurality of lesion navigation modules can be arranged according to actual conditions. In addition, in some specific cases, some lesion navigation modules are combined with the dirty surface navigation module because they are closer to the dirty surface navigation module.

The lesion navigation module 3 is matched with the hollowed-out part in the middle of the diaphragmatic surface navigation module 1. The lesion navigation module 3 can be matched with the hollowed-out part in the middle of the visceral surface navigation module 2 as required.

Each module is connected by a sealing strip, wherein the diaphragm surface sealing strip 1-1 is connected to the visceral surface sealing strip 2-1, and the lesion periphery sealing strip 3-1 is connected to the diaphragm surface inner sealing strip 1-2.

The distribution of the grooves 1-3 of the diaphragmatic navigation module and the grooves 2-2 of the visceral navigation module are marked and set according to the specific anatomical segments of the liver surface, and the boundaries of the liver segments can be accurately marked.

The circular holes 1-4 are evenly distributed, which is conducive to observing the degree of fit between the module and the liver surface and is conducive to better fit of the module to the liver surface, thereby improving the accuracy of navigation positioning.

Each sealing strip is provided with a concave-convex matching mortise and tenon structure, and the grooves and protrusions on the two connected sealing strips fit each other to complete a tight connection. The diaphragm surface sealing strip 1-1 is provided with a diaphragm surface groove 1-1-1 and a diaphragm surface protrusion 1-1-2, and the visceral surface sealing strip 2-1 is provided with a visceral surface protrusion 2-1-1 and a visceral surface groove 2-1-2. Similarly, the lesion sealing strip 3-1 is provided with grooves and protrusions (not shown in the figure). Through the precise matching of the corresponding grooves and protrusions on the sealing strips, the diaphragm surface navigation module 1 and the visceral surface navigation module 2 are closed into one. Similarly, the lesion navigation module 3 and the diaphragm surface navigation module 1 are also combined through the concave-convex matching mortise and tenon structure of the sealing strip.

After the navigation module is used, a thin metal sheet should be inserted into the gap between the upper and lower sealing strips, and the sealing strips should be rotated and stretched open until the mortise and tenon joints are disengaged.

The present invention provides a new accurate liver surgery navigation and positioning device based on liver surgery navigation and positioning by comprehensively applying multidisciplinary technologies such as medical imaging, computer three-dimensional imaging, medical engineering, 3D printing and surgical operations. The design principle of the present invention is to construct a digital three-dimensional liver according to imaging, and then generate and mark the boundary lines and lesion areas of each liver segment according to the internal structure of the liver, including the distribution of the hepatic artery, portal vein, hepatic duct structure and the three-dimensional anatomical structure of the lesion (if any). Among them, the area of the lesion is vertically projected to the liver surface with the shortest distance. The anatomical segmentation of the liver adopts the classic Couinaud method, which divides the liver into 8 segments based on the various perfusion areas of the portal vein system (left hemiliver, right anterior lobe, right posterior lobe) and the hepatic veins (left, middle and right hepatic veins).

In order to generate the navigation and positioning module, the three-dimensional data of the liver surface are extracted, including the above-mentioned liver segment demarcation line and the three-dimensional projection area of the lesion. Given that the imaging has a certain thickness, the extracted three-dimensional data of the liver surface have uneven noise points. Using the Gaussian algorithm, the above-mentioned noise points are smoothed so that the extracted liver surface is basically consistent with the real liver surface. The three-dimensional data of the liver surface is generated into a format that can be displayed in three dimensions, which is the so-called digital liver surface module. Generally, according to the surface of the liver, the liver surface module is divided into two parts: the diaphragmatic surface and the visceral surface. The diaphragmatic surface and the visceral surface can be simply understood as the upper and lower sides of the liver, and finally they are printed using 3D printing technology.

The present invention designs a navigation device during liver surgery, and the generated module is used to mark the various segments and lesion boundaries of the liver surface. By acquiring the imaging data of the liver image scan, a digital three-dimensional liver is constructed according to the imaging data, and at the same time, according to the distribution of the ducts and lesions inside the liver, the three-dimensional structure of each liver segment and lesion is divided on the digital liver, and the three-dimensional data of the boundary lines of the above-mentioned liver segments and lesions are extracted. The digital liver navigation module is designed and generated, and the above-mentioned liver navigation positioning module is 3D printed to directly distinguish and mark the surface boundary lines of liver segments and lesions during liver surgery. Through the surgical navigation positioning module of the present invention, an intuitive and clear liver surface boundary line is provided for liver surgeons, so that anatomical resection of specific liver segments can be carried out, surgical complications can be reduced, and the prognosis of surgical resection of liver tumor patients can be improved. The present invention combines the advantages of multiple disciplines and aims to solve the problem of precise liver segment resection surgery. Through the construction of a digital three-dimensional liver, intelligent liver segmentation, acquisition of surface boundary lines and lesion three-dimensional projections, and the design and production of a liver lesion navigation positioning module, the surgeon can easily identify the surface boundary line of the liver to be resected.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a top view of the diaphragmatic surface navigation module, the visceral surface navigation module, and the lesion navigation module.

FIG. 2 shows a schematic diagram of the closure of the modules by means of the mortise and tenon joints formed by the closing strips.

FIG3 shows a schematic diagram of the manufacturing principle of the liver surgery navigation system of the present invention.

FIG4 shows a flowchart of the implementation of the liver surgery navigation and positioning module.

FIG. 5 shows a schematic diagram of an implementation of a liver surgery navigation and positioning module according to Embodiment 4.

FIG. 6 shows a schematic diagram of an implementation of a liver surgery navigation and positioning module according to Embodiment 5.

FIG. 7 shows a schematic diagram of an implementation of a liver surgery navigation and positioning module according to Embodiment 6.

Detailed ways

In order to make the specific application and implementation process of the present invention clearer, the following is a clear and complete description of the technical solution of the present invention in combination with the drawings and embodiments of the present invention. The described embodiments are part of the embodiments of the present invention, including but not limited to the described contents.

Example 1

Referring to Figures 1 and 2, a navigation and positioning device for liver surgery is composed of three modules: a diaphragmatic navigation module 1, a visceral navigation module 2, and a lesion navigation module 3. Since the liver is a three-dimensional structure, the diaphragmatic surface is the upper surface of the liver, and the visceral surface is the lower surface of the liver.

A diaphragm surface sealing strip 1-1 is arranged around the diaphragm surface navigation module 1, the middle of the diaphragm surface navigation module 1 is hollowed out and provided with a diaphragm surface inner sealing strip 1-2, and a diaphragm surface navigation module groove 1-3 and a circular hole 1-4 are arranged on the surface of the diaphragm surface navigation module 1.

A dirty surface sealing strip 2-1 is arranged around the dirty surface navigation module 2, a dirty surface navigation module groove 2-2 is arranged on the surface of the dirty surface navigation module 2, and a circular hole (not shown in the figure) which is the same as that of the diaphragm surface navigation module 1 is also arranged.

A lesion sealing strip 3-1 is arranged around the lesion navigation module 3, wherein there may be multiple lesion navigation modules 3 according to actual conditions. In some specific cases, some lesion navigation modules are closer to the visceral surface navigation module, so the lesion navigation module is combined with the visceral surface navigation module.

The hollowed-out parts in the middle of the lesion navigation module 3 and the diaphragm surface navigation module 1 in FIG1 are matched, and each module is connected by a sealing strip, wherein the diaphragm surface sealing strip 1-1 is connected to the visceral surface sealing strip 2-1, and the lesion sealing strip 3-1 is connected to the diaphragm surface inner sealing strip 1-2.

The distribution of grooves 1-3 of the diaphragmatic navigation module and grooves 2-2 of the visceral navigation module are marked and set according to the specific anatomical segments of the liver surface. The liver segments are divided according to the classic Couinaud method based on the various perfusion areas of the portal vein and hepatic vein. The groove structure of the navigation module can accurately mark the boundaries of the liver segments during surgery.

Each navigation module has evenly distributed circular holes on its surface, such as the circular holes 1-4 in the diaphragmatic navigation module in Figure 1. The circular holes in the visceral navigation module and the lesion navigation module are set in the same way. Setting the circular holes in this way is conducive to observing the degree of fit between the module and the liver surface, so as to facilitate the module to better fit the liver surface, thereby improving the accuracy of navigation positioning.

Referring to Figure 2, each closing strip is provided with a concave-convex matching mortise and tenon structure, that is, each closing strip is provided with grooves and protrusions. When the diaphragm surface navigation module 1 is connected with the visceral surface navigation module 2, the diaphragm surface groove 1-1-1 and the diaphragm surface protrusion 1-1-2 on the diaphragm surface closing strip 1-1 are matched with the visceral surface groove 2-1-2 and the visceral surface protrusion 2-1-1 on the visceral surface navigation module closing strip 2-1, thereby completing the closing or separation between the modules. Similarly, when the lesion navigation module 3 is hollowed out in the middle of the diaphragm surface navigation module 1, the grooves and protrusions on the lesion closing strip 3-1 of the lesion navigation module 3 are matched with the grooves and protrusions on the diaphragm inner closing strip 1-2 (not shown in the figure), thereby completing the closing or separation between the lesion navigation module 3 and the diaphragm surface navigation module 1.

The projections and grooves of the concave-convex matching mortise and tenon structure are set in different sizes. For example, the diaphragm surface groove 1-1-1 is a small matching mortise and tenon groove, the dirty surface groove 2-1-2 is a large matching mortise and tenon groove, the diaphragm surface protrusion 1-1-2 is a large matching mortise and tenon protrusion, and the dirty surface protrusion 2-1-1 is a small matching mortise and tenon protrusion. The grooves and protrusions of different sizes make the matching between the closing strips more complete and tight, and to a certain extent prevent some unnecessary misalignment matching. The navigation module is separated by inserting a thin metal sheet into the gap between the upper and lower closing strips, rotating and propping the closing strips until the concave-convex matching mortise and tenon are disengaged. Thereby separating the connection between each module.

Example 2

Referring to FIG3 , the device of the present invention is prepared by the following steps:

1. Acquisition of imaging information: Through the patient's preoperative thin-layer enhanced CT examination of the liver, the CT images are obtained as DICOM standard images, and the images of each phase of the plain scan phase, arterial phase, portal vein phase and hepatic vein phase are selected.

2. Construction of digital 3D liver: The constructed 3D liver includes the internal structure of the liver, including the hepatic artery, portal vein, hepatic vein, inferior vena cava, hepatic duct, bile duct, gallbladder, lesions and perihepatic ligaments. First, the outline of the liver is marked in the thin-layer enhanced CT image of the liver, so as to basically determine the reconstruction range of the digital three-dimensional liver, including the marking of the gallbladder, common bile duct, and common hepatic duct; second, in the hepatic artery phase CT image, the enhanced abdominal aorta, celiac artery, common hepatic artery, proper hepatic artery, left hepatic artery, right hepatic artery, and small branches of the intrahepatic artery are marked; third, in the portal vein phase CT image, the enhanced portal vein trunk, left branch of the portal vein, right branch of the portal vein, sagittal part of the portal vein, right anterior branch of the portal vein, right posterior branch of the portal vein and other small branches of the portal vein are marked; fourth, in the hepatic venous phase CT image, the right hepatic vein, middle hepatic vein, left hepatic vein and inferior vena cava are marked; fifth, if the intrahepatic bile duct is dilated, the intrahepatic bile duct is further marked, and the hepatic ligament structures such as the round ligament of the liver are marked; sixth, the outline of the intrahepatic lesion is marked, and the remaining structures within the liver outline (excluding the above-mentioned marked structures) are the normal liver tissue range. The Gaussian algorithm is used to convert the two-dimensional graphics into a three-dimensional image, so as to construct a digital three-dimensional liver.

3. Liver segmentation: The boundary lines of each liver segment are divided according to the distribution of the branches and tributaries of the portal vein and hepatic vein, and the marks of each liver segment are placed on the surface of the digital three-dimensional liver. The boundary line between each liver segment and the boundary line of the lesion are the two-dimensional projection contour of the liver surface closest to the lesion.

4. Lesion demarcation: Liver lesions are projected onto the liver surface closest to them, so that the contour demarcation line of the lesion is presented on the digital 3D liver surface. Sometimes the lesion is closer to the diaphragmatic surface of the liver, and sometimes it is closer to the liver surface. Depending on the specific situation, it will be projected onto the corresponding liver surface.

5. Extract the three-dimensional data of the liver surface, including the segmentation of the liver and the boundary information of the lesion.

6. Perform artificial noise reduction on the extracted data to make the surface of the digital liver smooth. The smaller the thickness between each layer of thin-layer CT, the less artificial noise reduction intervention is needed, and the three-dimensional image is closer to the real liver.

7. Production of each module: The three-dimensional liver surface data extracted in the above steps are edited, and the main contents of the editing are as follows. First, a certain thickness (5 mm) is given to the liver surface; second, the liver surface is filled with evenly distributed circular holes; third, a certain width (5 mm) is given to the boundary line of the liver segment; fourth, the part where the lesion is projected on the liver surface is extracted, and the diaphragm surface navigation module, visceral surface navigation module and lesion navigation module have been basically generated; fifth, the sealing strip is set around the diaphragm surface navigation module, visceral surface navigation module and lesion navigation module.

8. Generate a file suitable for 3D printing format from the above navigation module, and complete the production of the navigation module after 3D printing. The navigation module of the present invention is suitable for intraoperative navigation positioning in most cases, but it needs to be adjusted accordingly according to the actual situation during the specific implementation process. The adjustment includes: the number of lesion navigation modules, the location of the lesion navigation modules, and the groove distribution inside the navigation module.

Example 3

In the preoperative evaluation project for liver surgery patients, a liver CT examination is included. The DICOM standard image information of each phase of the thin-layer liver enhanced CT is obtained by following the steps in Example 3, which is used for the subsequent reconstruction of the three-dimensional digital liver by open source software (3D slicer, https://www.slicer.org/). During the implementation process, the purpose of selecting a thin-layer liver CT for three-dimensional reconstruction is to more accurately simulate the state of the real liver (the thickness of a common liver CT is 5 mm per layer, and the thickness of a thin-layer liver CT is generally 1 mm per layer). In addition, the internal structures of the liver, such as the hepatic artery, hepatic duct, portal vein, hepatic vein, lesions, etc., are marked by artificial marking, and the tissue structures extending outside the liver, such as the inferior vena cava, common bile duct, gallbladder and other structures are also marked.

The purpose of the above marking is to further segment the three-dimensional digital liver and project the lesion on the liver surface. The segmentation of the three-dimensional digital liver is completely carried out according to the distribution structure of the portal vein and hepatic vein inside the liver.

After completing the segmentation of the 3D digital liver and projecting the lesion on the liver surface, the liver surface data information is extracted. By editing the surface structure, the digital liver capsule is smoothed to eliminate the jagged noise to accurately simulate the state of the real liver. The above editing is achieved through software (zbrush 2018, Pixologic, https://pixologic.com/).

The digital versions of the generated liver segment navigation and positioning module and the liver lesion navigation and positioning module (as shown in FIG1 ) are 3D printed using medical photosensitive resin.

FIG1 is a structural diagram of the liver segment navigation positioning module and the liver lesion navigation positioning module after further software editing and generation, wherein 1 is the diaphragmatic surface navigation module, 2 is the visceral surface navigation module, and 3 is the lesion navigation module. Because the lesion in the case of FIG1 is close to the diaphragmatic surface module, the lesion navigation module is set to match the hollowed-out part in the middle of the diaphragmatic surface navigation module. As shown in FIG2, a concave-convex anastomotic mortise and tenon structure is set on the closing strip of each module (FIG. 2A), and the diaphragmatic surface closing strip 1-1 and the visceral surface closing strip 2-1 are concave-convex anastomotic (FIG. 2B). The reason for such separate settings is that the various navigation modules can be combined or disassembled, thereby facilitating the adjustment of the various navigation modules as needed during the operation. The diaphragmatic surface groove 1-3 structural setting is to outline the boundary of the diaphragmatic surface segmentation of the liver, and the visceral surface groove 2-2 structural setting is to outline the boundary of the visceral surface segmentation of the liver. There are evenly arranged circular holes 1-4 in the middle of each module, which are hollowed out (usually with a diameter of 5 mm, which can be adjusted according to the size of the module). The reason for this setting is to minimize the use of materials without reducing the strength of the three-dimensional structure, and it is also conducive to observing the fit between the module and the liver.

Each navigation module closing strip is provided with a concave-convex fitting mortise and tenon structure, which can better make the fitting between the connected module closing strips more complete and tight, and to a certain extent prevent some unnecessary misalignment, while at the same time, each navigation module can be combined or disassembled as needed.

Example 4

In the actual application of the navigation and positioning module of the present invention, the basic operation is as shown in FIG4. First, the diaphragm surface and visceral surface navigation and positioning modules are attached to the liver surface, and then the concave and convex anastomosis mortise and tenon joints are closed by finger pressure, so that the closed diaphragm surface and visceral surface modules are fixedly attached to the liver surface without being affected by external forces. Then, the lesion navigation and positioning module is combined with the liver segment navigation and positioning module through a similar concave and convex anastomosis mortise and tenon joint structure.

Use the intraoperative electrocoagulation device to mark the boundary line of the liver segment to be removed on the liver surface, then use forceps or vascular clamps to remove the liver lesion navigation and positioning module from the diaphragm surface positioning module, and then use the electrocoagulation device to mark the boundary line of the lesion on the liver surface. Finally, insert a thin metal sheet into the gap between the upper and lower sealing strips, rotate and open the sealing strip until the concave and convex joints are disengaged, remove all the liver navigation and positioning modules, and further perform surgical resection of the liver segment.

Fig. 5 is a schematic diagram of the implementation of the liver surgery navigation and positioning module during the operation, wherein A shows that the diaphragmatic navigation module 1 and the visceral navigation module 2 are attached to the liver 4, and the upper and lower edge sealing strips are pressed hard to close the concave and convex tenon and mortise structures inside. B shows that the lesion navigation module 3 is closed to the diaphragmatic navigation module 2. C shows a sagittal cross-sectional view after the navigation module is closed to the liver, and each navigation module is tightly attached to the surface of the liver. After the navigation module is used, a thin metal sheet should be inserted into the gap between the upper and lower sealing strips, and the sealing strip should be rotated to open until the matching tenon and mortise are disengaged.

Example 5

When the position and size of the lesion of the liver change, the position and size of the lesion navigation module also change accordingly. As shown in Figure 6, when the lesion is close to the liver surface, the lesion navigation module 7 is arranged on the visceral surface navigation module 6. D shows that the diaphragmatic surface navigation module 5 and the visceral surface navigation module 6 are fitted to the liver 8, and the sealing strips of the upper and lower edges are pressed hard to close the concave and convex tenon and mortise structure inside. E shows that the lesion navigation module 7 is closed to the visceral surface navigation module 6. F shows a sagittal cross-sectional view after the navigation module is closed to the liver, and each navigation module is closely fitted to the liver surface. After the navigation module is used, a thin metal sheet is inserted into the gap between the upper and lower sealing strips, and the sealing strip is rotated to open until the matching tenon and mortise are disengaged.

Example 6

When there are multiple lesions in the liver, especially when multiple lesions are distributed on the diaphragmatic surface and the visceral surface of the liver, it is necessary to set the position of the lesion navigation module in the diaphragmatic surface navigation module and the visceral surface navigation module respectively. When two lesions are located on the diaphragmatic surface and the liver surface, as shown in Figure 7, the first lesion navigation module 11 and the second lesion navigation module 12 are respectively matched with the diaphragmatic surface navigation module 9 and the visceral surface navigation module 10. G shows that the diaphragmatic surface navigation module 9 and the visceral surface navigation module 10 are fitted to the liver 13, and the upper and lower edges of the sealing strips are pressed hard to close the concave and convex tenon and mortise structure inside. H shows that the first lesion navigation module 11 is closed to the diaphragmatic surface navigation module 9, I shows that the second lesion navigation module 12 is closed to the diaphragmatic surface navigation module 10, and J shows the sagittal cross-sectional view after the navigation module is closed to the liver, and each navigation module is closely fitted to the liver surface. After the navigation module is used, a thin metal sheet is inserted into the gap between the upper and lower sealing strips, and the sealing strip is rotated to open until the matching tenon and mortise are disengaged.

According to the navigation and positioning module of liver surgery generated by the present invention, the surface is uniformly hollowed out with small circular holes, which is conducive to observing the degree of fit during implementation; the groove design is conducive to marking the boundary of the liver segment during surgery, and the module periphery is completely closed and connected with the groove to maintain its three-dimensional shape. In addition, in this embodiment, the liver lesion navigation and positioning module is a single module close to the diaphragm surface. If there are multiple lesions or close to the visceral surface in a specific case, the corresponding number and position can be set according to the actual situation. The lesion navigation module and the diaphragm surface/visceral surface navigation module are detachable through the mortise and tenon structure, which has the following advantages: when the lesion diameter is too large, when the liver segment navigation and positioning module is attached to the liver surface, an excessive error will be generated, thereby affecting the accurate navigation and positioning of the liver segment. At this time, the liver lesion navigation and positioning module and the liver segment navigation and positioning module are used in combination to minimize the error caused by incomplete fitting. When the location of the liver tumor needs to be marked, the liver lesion navigation and positioning module can be removed to facilitate intraoperative marking. This combination and disassembly design is conducive to the smooth progress of surgical navigation.

Claims (6)

1. A precise liver surgery navigation positioning device, characterized in that the positioning device is composed of three modules, namely, a diaphragm surface navigation module (1), a visceral surface navigation module (2) and a lesion navigation module (3); a diaphragm surface sealing strip (1-1) is provided around the diaphragm surface navigation module (1); the middle of the diaphragm surface navigation module (1) is hollowed out and provided with a diaphragm surface inner sealing strip (1-2); a diaphragm surface navigation module groove (1-3) and a circular hole (1-4) are provided on the surface of the diaphragm surface navigation module (1); a visceral surface sealing strip (2-1) is provided around the visceral surface navigation module (2); a visceral surface navigation module groove (2-2) and a circular hole are provided on the surface of the visceral surface navigation module (2); and a lesion navigation module (3) is provided with a lesion sealing strip (3-1); the modules are connected to each other via sealing strips; the diaphragm surface sealing strip (1-1) is connected to the visceral surface sealing strip (2-1); and the lesion sealing strip (3-1) is connected to the diaphragm surface inner sealing strip (1-2); Each of the sealing strips is provided with a concave-convex matching mortise and tenon structure, and the concave-convex matching mortise and tenon structure of the two sealing strips to be connected fit with each other; The diaphragm surface sealing strip (1-1) is provided with a diaphragm surface groove (1-1-1) and a diaphragm surface protrusion (1-1-2), and the visceral surface navigation module sealing strip (2-1) is provided with a visceral surface groove (2-1-2) and a visceral surface protrusion (2-1-1). Similarly, the lesion sealing strip (3-1) is provided with a groove and a protrusion. 2. A precise liver surgery navigation and positioning device according to claim 1, characterized in that, when the diaphragm surface navigation module (1) is connected to the visceral surface navigation module (2), the diaphragm surface groove (1-1-1) fits with the visceral surface protrusion (2-1-1), and the diaphragm surface protrusion (1-1-2) fits with the visceral surface groove (2-1-2); when the lesion navigation module (3) is connected to the diaphragm surface navigation module (1), the groove and protrusion arranged on the lesion sealing strip (3-1) fit with the groove and protrusion on the diaphragm inner sealing strip (1-2). 3. The precise liver surgery navigation and positioning device according to claim 1, characterized in that a plurality of lesion navigation modules (3) are provided according to actual conditions. 4. A precise liver surgery navigation and positioning device according to claim 1, characterized in that the lesion navigation module (3) is combined with the diaphragmatic surface navigation module (1), or with the visceral surface navigation module (2). 5. The precise liver surgery navigation and positioning device according to claim 1, characterized in that the lesion navigation module (3) is combined with the hollow part in the middle of the diaphragm navigation module (1). 6. The method for preparing a precise liver surgery navigation and positioning device according to claim 1, characterized in that it is achieved by the following steps: (1) Acquisition of image information: Select images of each phase, including the plain scan phase, arterial phase, portal venous phase, and hepatic venous phase, and obtain CT images as DICOM standard images; (2) Construction of a digital three-dimensional liver: Based on the DICOM standard CT images, the Gaussian algorithm is used to convert the two-dimensional graphics into three-dimensional images, thereby constructing a three-dimensional liver, including the internal structure of the liver: the hepatic artery, portal vein, hepatic vein, inferior vena cava, hepatic duct, bile duct, gallbladder, lesions, and the structure of the perihepatic ligaments; (3) Liver segmentation: The boundaries of each liver segment are divided according to the distribution of the branches and tributaries of the portal vein and hepatic vein, and each liver segment is marked on the surface of the digital 3D liver; as well as the boundary line of the lesion; (4) Lesion demarcation: The liver lesion is projected onto the liver surface closest to it, so that the contour demarcation line of the lesion is presented on the digital three-dimensional liver surface. Sometimes the lesion is closer to the diaphragmatic surface of the liver, and sometimes the lesion is closer to the liver surface. It will be projected onto the corresponding liver surface according to the specific situation. (5) extracting the three-dimensional data of the liver surface, including the segmentation of the liver and the boundary information of the lesion; (6) Performing artificial noise reduction on the extracted data to make the surface of the digital liver smooth; (7) Production of each module: The three-dimensional liver surface data extracted in the above steps are edited. The main contents of the editing are as follows: first, a certain thickness (5 mm) is given to the liver surface; second, the liver surface is filled with evenly distributed circular holes; third, a certain width (5 mm) is given to the boundary line of the liver segment; fourth, the part of the lesion projected on the liver surface is extracted. At this point, the diaphragm surface navigation module, the visceral surface navigation module and the lesion navigation module have been basically generated; fifth, a sealing strip is set on the diaphragm surface navigation module, the visceral surface navigation module and the lesion navigation module; (8) Generate the above navigation module into a file in a format suitable for 3D printing, and perform 3D printing to complete the production of the navigation module.