KR101301477B1 - Radiopaque Marker for Multiple Images Merging or Synchronization - Google Patents

Abstract

The present invention relates to a marker for image registration or coordinate synchronization, and more particularly, oral fittings used for matching or imaging heterogeneous images used in processing and procedures based on images such as intraoral procedures and gamma knife procedures for head and neck. It is a marker for image registration or coordinate synchronization used to easily synchronize the machining coordinates for machining.
The marker for image registration or coordinate synchronization of the present invention is a marker used for matching heterogeneous images or synchronizing coordinates, the first body being used for image registration or coordinate synchronization, and formed on the first body, And a second body part configured to be connected to the first body to detect the coordinates and to fix the marker to an object on which the marker is installed.
According to the image matching or coordinate synchronization marker of the present invention, it is possible to simply and precisely match heterogeneous images constituting the craniofacial image, perform image registration and coordinate synchronization using a single marker, and easily marker It can be fixed securely.

Description

Radiopaque markers for heterogeneous image registration or coordinate synchronization {Radiopaque Marker for Multiple Images Merging or Synchronization}

The present invention relates to a marker for heterogeneous image registration or coordinate synchronization, and to a device for performing a simulation for a surgical procedure or manufacturing a device used for a surgical procedure by using an image, coordinate synchronization for implantation of a processed coordinate. For markers used in.

The craniofacial region, which is included in the head and neck, is a tissue part of the human body in which various procedures such as brain tumor removal and implant surgery are performed. We use for.

In the case of brain tumor removal procedure, after acquiring three-dimensional images of the craniofacial part of the patient, the three-dimensional gamma-irradiation control device such as gamma knife is used to remove the lesions on the acquired images. A precise 3D image is required, but the conventional CT image has a limitation in obtaining such an accurate image, and in order to obtain a precise image, registration of various images for the craniofacial region is essential.

In addition, in the case of implant surgery, orthopedic surgery and plastic surgery, the surgical guide fixture is operated in the oral cavity, and the patient's intraoral cavity is used rather than using direct data such as the CT data of the patient for the accuracy of the mounting. It is advantageous to build using data from a model that mimics the organization.

In addition, in the case of digital articulator, the three-dimensional CT image for acquiring the location information of the mandibular condyle, which is the axis of motion for the analysis of occlusal motion, and the three-dimensional of the intraoral tissue with high resolution to accurately analyze the occlusal relationship It is desirable to match the shape of the scanned image or the oral tissue.

To this end, there was a need to precisely match images containing internal tissue information of patients such as scan images of intraoral tissues and 3D CT images or MRI images. Even when used without matching due to the complicated or matching, there is a problem that the matching error is large and precise and accurate matching is not made due to the low resolution as the matching is performed using the feature points such as teeth.

In addition, although a device for conventional matching is separately prepared, registration is performed using an image of the device for matching to image matching. However, due to the characteristics of tomography, image information of the marker is distorted, and thus matching accuracy is lowered.

In addition, in order to process the fittings used for surgical procedures, such as using imaging or direct procedure planning, the mountings must be processed according to the established procedure and the processing information must be transmitted to the processing equipment. The process of transmitting the processing information is complicated, such as inputting to the processing device or converting the image coordinate system into the processing coordinate system. The processing information itself is also inferior in accuracy as the accuracy of the image itself decreases. come.

In addition, the image registration and coordinate synchronization is separate, the processing of the oral attachment is complicated, there is a problem that the fixed part of the marker is vulnerable and difficult to secure the fixed.

The present invention is to solve the above problems, an object of the present invention is to increase the accuracy of the image registration and coordinate synchronization can be performed at the same time, the image registration that can be easily and reliably fixed to the object to install the marker or The present invention provides a marker for coordinate synchronization.

In order to achieve the above object, the marker for image registration or coordinate synchronization of the present invention is a marker used for matching heterogeneous images or synchronizing coordinates, the first body part being used for image registration or coordinate synchronization, and It is connected to the first body portion includes a second body portion for fixing the marker to the object on which the marker is installed.

In addition, the first body portion is characterized in that it further comprises a cover portion for detecting the coordinates of the marker.

In addition, the cover portion is characterized in that the protruding or recessed portion provided on the upper or side portion of the first body portion.

In addition, the cover portion is characterized in that the shape of any one of a cylinder, a cone, a truncated cone, a sphere, a polygonal pillar, a polygonal pyramid or a polygonal pyramid.

In addition, the cover portion is characterized in that it further comprises a stepped step portion relative to the first body portion in the outer shape.

In addition, the first body portion is made of a cylindrical or polygonal column or a portion of the hyeonja consisting of a line segment, characterized in that the tapered shape of the cross-section narrowed toward the coupling portion with the second body portion.

In addition, the second body portion is made of a cylindrical or polygonal shape, characterized in that the tapered shape of the cross-section narrowed toward the coupling portion with the first body portion.

In addition, the second body portion is formed in the shape of a cylinder or a polygonal pillar, characterized in that it comprises a stepped stepped portion on all or part of the side.

In addition, the first body portion or the label portion is characterized in that made of a radiopaque material.

The first body portion or the label portion may have a density of 1 g / cm 3 or more and 7.0 g / cm 3 or less.

In addition, the first body portion is characterized in that the radius of the inscribed circle or circumscribed circle of the upper surface or the lower surface or the cross-sectional shape is at least 1mm or more.

In addition, the first body portion is characterized in that it comprises a tooth shape for utilization in the oral prosthesis or occlusal relationship.

The present invention of the above configuration has the effect that can easily and precisely match the heterogeneous images constituting the craniofacial image.

In addition, there is an effect that registration of images using various imaging devices such as CT tomography can be performed with high precision.

In addition, the side surface of the marker is tapered so as to have a predetermined inclination, so that the shape of the marker can be accurately recognized.

In addition, by the shape of the marker portion of the marker to facilitate the contact with the contactable contact detector as a result has the effect of increasing the reference point extraction accuracy and easy extraction process.

In addition, it is possible to simultaneously perform image registration and coordinate synchronization using one marker.

In addition, there is an effect that can be easily and reliably fixed to the marker on the object.

1 is a perspective view of a marker for image registration or coordinate synchronization according to an embodiment of the present invention;
2A to 2D are perspective views illustrating various forms of a marker according to an embodiment of the present invention.
3 is a perspective view showing a coupling type of the marker according to an embodiment of the present invention,
4A to 4D are views illustrating a process of selecting a reference point in various situations in the marker of the present invention.
5 is a diagram illustrating a process of calculating a reference point of the first body part from the reference points selected in FIGS. 4A to 4D.

Hereinafter, a marker for image registration or coordinate synchronization according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing an example of an image registration or coordinate synchronization marker of the present invention, which is used to fix a marker to an object 10 to which a first body part 100 and a marker are used for image registration or coordinate synchronization. In order to implant the second body portion 200 and the processing information and the like to the processing apparatus, the cover portion 300 is used for coordinate detection and the like to synchronize the processing information in the coordinate system such as the processing apparatus.

The first body part 100 is a configuration used for image registration or coordinate synchronization. As described above, images are used for various procedures. In this image, a plurality of images are used instead of a single image, and the first body part 100 is used. Is used to match these plurality of images. When registering a plurality of image registration using the image of the first body portion 100 included in the image bar CT, MRI, etc. When an image of tomography is used for the procedure, the first body portion 100 is a radiopaque material It is preferable that it consists of. In addition, it is preferable that the density is 1 g / cm 3 or more and 7.0 g / cm 3 in order to distinguish it from the oral tissue in the image. This is because when the density of the first body part 100 is 1 g / cm 3 or less, similar to the soft tissue image value, there is a problem in that the marker is lost during the segmentation process, and when 7.0 g / cm 3 or more, metal artifact occurs, This is because the image of the image may be deteriorated unless the current voltage value is increased.

The shape of the first body portion 100 is preferably made of any one of a cylinder, a polygonal pillar or a string of a portion consisting of a line segment. This is because the accuracy and convenience in obtaining different types of images including the first body part 100 and matching heterogeneous images using the images of the first body part 100 can be guaranteed when the images are matched. to be.

When explaining an example of the image registration process using the image registration or coordinate synchronization marker of the present invention through an implant procedure using an image attached to the tray for mounting the image registration or coordinate synchronization marker of the present invention in the oral cavity Images of the head and neck are obtained through tomography devices such as CT and MRI. In order to obtain intraoral tissue information such as dentition, a plaster model including dentition is produced using impression material to obtain an image of the plaster model together with the tray. Images included in the head and neck portion through the above process includes a marker for image registration or coordinate synchronization, more precisely, an image of the first body portion 100, and the image of the first body portion 100 using simple image processing. You can extract the outline. In the conventional image registration method using a marker, the image processing is complicated and its precision is very low because the image is matched by matching the image of the marker, as described above. Image registration using the marker of the present invention to solve this problem is to extract three or more points from the outline extracted from the image of the first body portion 100 (circle in the case of a cylinder, polygonal or string in the case of a vertebral column) After extraction, three points from the extracted points are selected to calculate a circle passing through all the selected points. There may be various methods for extracting the points from the outline, but the user may extract them by clicking on the image including the first body part 100. In this case, more precise extraction is possible and accordingly, more precise image registration is performed. There is an advantage. Of course, it can also be automated to extract three points arbitrarily from the extracted outline.

Referring to FIGS. 4A to 4D, a process of calculating a reference point representing the first body part 100 from the image of the first body part 100 in the image is described. FIG. 4A illustrates that the first body part 100 is tomographically photographed. It shows the process of calculating the reference point when placed obliquely on the slice plane. More precisely, the single-layer slice surface cuts off the reference surface of the first body part 100, and the cross section formed is a curved line including a straight line. A tomographic image of the first body part 100 according to the movement of the slice surface is shown in sequence. When the shape of the first body portion 100 is a cylinder, the shape of the closed curve including the string is shown as being inclined to the slice surface. The length of the closed curve changes little by little as the movement of. In this case, selecting the edge point where the closed curve and the string meet as the reference point of the first body part 100 may calculate the reference point of the first body part 100 by using the more accurately selected reference points and selected from FIG. 4A. Three or more than three reference points are shown on the left figure of FIG. 5. After calculating a circle passing all three or three or more selected points, the center point of the circle is used as a reference point of the first body part 100. In this process, since the mathematical process is already included in the process of creating a circle from three or more than three reference points, the corrected reference point can be extracted, and thus the first body part 100 located in the three-dimensional space Even if the position can be accurately represented and the point-to-point matching is used for image matching, the probability of mismatch is very small.

4B illustrates a case in which the first body part 100 having the same shape as that of FIG. 4A is positioned parallel to the slice surface. In this case, a reference point is selected for a single slice surface for one marker, but the first or last circular edge that appears during the slice movement, such as the upper surface of the first body portion 100, of the cross section of the first body portion 100 is selected. Select the reference point. If the side surface of the first body portion 100 is tapered, the reference point should be selected on the outline shape by referring to the area corresponding to the surface where the reference point exists, such as the widest or narrowest section of the first body portion. will be. The selected reference point is shown in FIG. 5, similar to FIG. 4A, and uses the center of the calculated circle as a reference point of the first body part 100.

Figure 4c shows a case where the first body portion 100 is cut by the slice surface, more precisely when the cross section of the first body portion 100 by the slice surface is represented by a square or trapezoid by the angle of the surface. Say. In this case, the boundary between the surface from which the reference point is extracted on the first body portion 100 and the ground surface of the first body portion becomes two vertices that are the most acute angles among the quadrilateral or the trapezoid, so that the acute vertices appearing while moving the slice surface are referred to as reference points. Select, but it is preferable to select to cross up or down according to the movement of the slice surface.

Figure 4d is a case of selecting a reference point on the upper or lower outline in the three-dimensional image after reconstructing into a three-dimensional image without selecting a reference point in the CT cross-section. It is preferable to select a large interval between the edges and to select a vertex when the outline is a polygon. The processing by the selected three points is the same as in the case of 4a.

After extracting three points from the outline as above, a circle passing all three points is generated and the center is used as a reference point of the first body part 100 to be used for image registration. In the case of calculating and using the reference point, the processing is much simpler than the image matching process through the conventional image matching, and the accuracy is significantly increased compared to the conventional one by matching the image by point to point. have.

In addition, in the case of the first body part 100 of the present invention, the side surface is formed in a tapered shape, and the diameters of the upper and lower surfaces of the first body part 100 are different. In setting the reference point of the first body part 100 in the automated image processing, if the upper surface and the lower surface have the same diameter, the determination of which center to set as the reference point is included separately, and between the reference points When matching, the centers of different marker faces are set as reference points, which may cause an error in matching or inaccurate matching. Therefore, when the side surface of the first body part 100 is formed in a tapered shape having a predetermined inclination, the upper and lower surfaces are different in shape so that accurate image matching can be achieved through accurate matching.

In addition, since the side surface of the first body part 100 is tapered, the same upper surface when the inclination values of the mesh data obtained from the plane of the upper surface (lower surface) are similar to each other based on the vector product history. It is determined that it exists on the plane, but since the vector product value changes rapidly as the repair vector value changes rapidly at the side portions other than the inscribed or circumscribed boundary, the vector product product is calculated and the outline of the plane transition portion (or the upper surface (lower surface)) is calculated. The vector dot value can be used as a threshold for the automatic detection of That is, there is an advantage that can automatically extract the edge (outer line) of the first body portion 100.

If the size of the first body portion 100, more precisely, the reference to extract the center circle, the size of the geometry related to the circle, chord, polygon inscribed, circumscribed circle diameter, or radius of the single-layered reconstruction surface for the contour extraction It should be at least twice the interval of. This is a value derived from the Nyquist theory, and it is generally preferable to use a value of 4 times larger than 2 times. That is, when calculating the minimum criterion to ensure the minimum registration accuracy, the diameter of the inscribed circle of the upper surface (lower surface) of the marker is preferably at least four times the slice interval of the tomography image, for example, the slice interval is 0.25mm Considering the slice spacing, the diameter of the outline (circle), polygon inscribed circle or circumscribed circle should be 2mm or more. This also accommodates all the curvatures of the circle, thereby reducing the geometrical curvature misjudgment into quadrilaterals and triangles, which can occur when there are two or three slices inside the circle.

The first body part 100 may be used for registration of images required for the implant procedure simulation. In this case, when the shape of the first body part 100 is a tooth shape, the implantation position of the implant can be easily simulated and the existing tooth Since the position where the occlusal relationship with is substantially reflected is reflected in the image to be simulated in advance, there is an effect that the implantation position of the precise implant can be easily set.

The first body portion 100 is preferably such that the cross section becomes narrower toward the coupling portion with the second body portion 200, which is easier to extract the upper surface of the first body portion 100 as an outline and attached with a marker. This is because the farther away from the object 10, the more clear the image of the first body part 100 and the interference with the object 10 is reduced.

The second body part 200 is configured to fix the marker to the object 10, which is formed in the shape of a cylinder or a polygonal column to more easily fix the marker to the object 10, and to prevent falling off after installation of the marker. 1 It is preferable that the cross section becomes narrower toward the coupling portion with the body part 100, that is, the cross section of the part fixed to the object 10 is larger so as not to be caught by the object 10 after being fixed to the object 10. Do. In addition, forming a stepped portion in part or all of the second body part 200 more reliably causes the marker to be coupled to the object 10 and has the effect of preventing rotation or play after being coupled to the object 10. have.

The first body part 100 and the second body part 200 may be manufactured in one piece, but may be separately manufactured to simplify the manufacturing process, and then may be combined in a fitting manner as shown in FIG. 3. Reference numeral 150 in FIG. 3 represents a portion in which the first body portion 100 and the second body portion 200 are coupled to each other.

The cover unit 300 is configured in a shape corresponding to the configuration for detecting the coordinates provided in the three-dimensional image acquisition device or processing device or the surgical device for the craniofacial part to synchronize the coordinate system of the matched image and the coordinate system in the processing device, etc. Used. The cover unit 300 may be formed in a protruding shape and a recessed shape in a shape of contacting or complementarily coupling a single point with a configuration for detecting coordinates. Of course, the cross-sectional shape may be formed of a circle, an arc including a string or a polygon inscribed or circumscribed to the circle. It may also be formed into a protrusion or depression, including the shape of a part or cone of a sphere. Any shape forms a shape complementary to the configuration for detecting the coordinates and is formed in a groove of a predetermined length or more in the case of a recessed type and a protrusion shape of a predetermined length or more in the case of a recessed type for accurate coupling with the coordinate detection configuration. In this case, it is preferable to be provided to be in contact with a single point. It must be formed in this way so that the coordinate synchronization is not possible because the coupling with the coordinate detection configuration is not coupled with a stiff or playable state.

In the coordinate synchronization, the position information for processing determined in the simulation using the cover part 300 and the image is present in one image coordinate system, and the position of the cover part 300 is determined by the coordinate detection configuration in the treatment apparatus or the processing apparatus. In this case, the processing vector or the processing position obtained through the simulation can be identified according to the deductive logic, and the processing information obtained by using the image can be synchronized with the processing apparatus. For this reason, the cover part 300 has the effect of performing coordinate synchronization more precisely because it is possible to contact more precisely and precisely to have the shape as mentioned above.

The cover portion 300 may be located on the upper side of the first body portion 100 to improve contact efficiency with the coordinate detection configuration, but may be located on the side surface. In addition, it is preferable to provide a stepped portion in the vicinity of the cover portion 300 is provided in terms of ensuring a reliable contact with the coordinate detection configuration.

First Body: 100 Second Body: 200
Cover part: 300

Claims (13)

In markers used to match heterogeneous images or to synchronize coordinates,
A first body part from which a reference point used for image registration or coordinate synchronization can be extracted;
A second body part connected to the first body part to fix the marker to an object on which the marker is installed,
Marker for image registration or coordinate synchronization, characterized in that the density of the first body portion is 1 g / cm 3 or more and 7.0 g / cm 3 or less.
In claim 1,
The marker for image registration or coordinate synchronization further comprises a cover unit formed on the first body portion for detecting the coordinates of the marker.
In claim 2,
The reference point extractable from the marker unit is an image registration or coordinate synchronization marker, characterized in that spaced apart in the same or a predetermined relationship to the reference point extractable from the first body.
In claim 2,
The marker for image registration or coordinate synchronization, characterized in that the cover portion is provided in the protruding or recessed portion on the upper or side portion of the first body.
In claim 4,
The marker is an image registration or coordinate synchronization marker, characterized in that the shape of any one of a cylinder, a cone, a truncated cone, a sphere, a polygonal pillar, a polygonal pyramid or a polygonal pyramid.
In claim 5,
The marker for image registration or coordinate synchronization further comprising a stepped stepped portion relative to the first body portion in the outer shape of the cover portion.
In claim 1,
The first body portion has a cylindrical or polygonal pillar or a portion of a string formed in the shape of a string, the image registration or coordinate synchronization, characterized in that the tapered shape of the cross-section narrowed toward the coupling portion with the second body portion Dragon marker.
In claim 1,
Marker for image registration or coordinate synchronization, characterized in that the second body portion is formed in the shape of a cylinder or polygonal pillar, the tapered shape is narrowed in cross section toward the coupling portion with the first body portion.
In claim 1,
Marker for image registration or coordinate synchronization, characterized in that the second body portion is made in the shape of a cylinder or polygonal pillar, and includes a stepped stepped portion on part or all of its side surfaces.
In claim 2,
Marker for image registration or coordinate synchronization, characterized in that the first body portion or the marker portion made of a radiopaque material.
In claim 2,
The marker for image registration or coordinate synchronization, characterized in that the density of the label portion is 1 g / cm 3 or more and 7.0 g / cm 3 or less.
In claim 1,
The first body portion markers for image registration or coordinate synchronization, characterized in that the radius of the inscribed circle or circumscribed circle of the upper surface or the lower surface or the cross section is at least 1mm or more.
In claim 1,
Marker for image registration or coordinate synchronization, characterized in that the first body portion comprises a tooth shape for utilization in the oral prosthesis or occlusal relationship.

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