KR20190007693A - Navigation apparatus and method for fracture correction - Google Patents

Abstract

The present invention relates to a navigation device for fracture correction and a method therefor. According to an embodiment of the present invention, a navigation device for fracture correction and a method therefor are to reduce the amount of radiation exposed to a patient. According to an embodiment of the present invention, a navigation method includes: a step of generating a first transformation 3D image on a patient′s bone which is not fractured, from a reference 3D image on the predetermined bone; a step of generating a second transformation 3D image by comparing the bone included in the first transformation 3D image with a 2D image photographed about the fractured bone of the patient after dividing the bone included in the first transformation 3D image into two parts; a step of extracting a change relation (C) between a first reference coordinate system which is set about a first bone part included in the second transformation 3D image and a second reference coordinate system which is set about a second bone part; a step of setting a third reference coordinate system about the first bone part included in the second transformation 3D image and setting a fourth reference coordinate system about the second bone part based on the extracted change relation (C); and a step of calculating a targeted correction rate of the fractured bone based on the position relation between the third and fourth reference coordinate systems.

Description

[0001] NAVIGATION APPARATUS AND METHOD FOR FRACTURE CORRECTION [0002]

The present invention relates to the field of navigation for medical procedures. More particularly, the present invention relates to a navigation apparatus and method for fracture correction.

In the existing orthodontic treatment and fracture modification, the surgical navigation device transmits preoperative and intraoperative images to deliver surgical information such as target points or surgical routes in the surgical planning. In this case, a 3D image such as a CT image is used before the operation, and a 2D image such as an X-ray image is used during operation. Surgical navigation system delivers the integrated information to the user by superimposing real-time intraoperative information including the position of the surgical tool on the preoperative image and the operation plan information.

However, in order to use the existing surgical navigation device, the CT imaging is required for the preoperative image, which may cause a lot of radiation exposure and cost problems.

A navigation apparatus and method for fracture correction according to an embodiment of the present invention aims at reducing a radiation dose to a patient.

Further, a navigation apparatus and method for fracture correction according to an embodiment of the present invention aims to improve the accuracy of a fracture correction procedure.

According to an embodiment of the present invention,

Generating a first modified 3D image for a non-fractured bone of a patient from a standard 3D image for a given bone; Dividing a bone included in the first modified 3D image into two parts and then creating a second modified 3D image by comparing the extracted bone with a 2D image photographed against a fractured bone of a patient; Extracting a transformation relationship (C) between a first reference coordinate system set for the first partial bone included in the second modified 3D image and a second reference coordinate system set for the second partial bone; Setting a third reference coordinate system for the first partial bone included in the second modified 3D image and setting a fourth reference coordinate system for the second partial bone based on the extracted transformation relation (C); And calculating a correction target value of the fractured bone based on a positional relationship between the third reference coordinate system and the fourth reference coordinate system.

Wherein generating the first modified 3D image comprises: matching each of the plurality of 2D images for the non-fractured bone of the patient to the standard 3D image; Transforming the standard 3D image so that a virtual 2D image generated from the standard 3D image corresponds to each of the plurality of 2D images; And generating the first modified 3D image by correcting each of the voxel values of the modified standard 3D image through an extrapolation method.

Wherein the step of generating the second deformed 3D image comprises the step of deforming at least one of the position and degree of rotation of the second partial bone relative to the first partial bone of the first deformed 3D image, And matching the resulting 2D image.

The step of extracting the transformation relation (C) comprises the steps of: extracting first feature points from bones included in the first modified 3D image; Extracting second feature points from the first partial bone and the second partial bone included in the second modified 3D image; (A) between the reference coordinate system set for the bones included in the first deformed 3D image and the first reference coordinate system by mapping the first feature points and the second feature points to the first deformed 3D image, Calculating a transformation relation (B) between the reference coordinate system set for the bone and the second reference coordinate system; And calculating the conversion relation (C) using the conversion relation (A) and the conversion relation (B).

The setting of the third reference coordinate system may include setting a third reference coordinate system in which a predetermined reference axis is parallel to the central axis of the first partial bone included in the second deformed 3D image.

The calculating of the calibration target value may include calculating an angulation when the second partial bone is moved so that a predetermined reference axis of the third reference coordinate system and a predetermined reference axis of the fourth reference coordinate system align with each other in the same direction, ) ≪ / RTI >

The calculating of the calibration target value may include calculating a rotation angle when the second partial bone is rotated such that axes other than the predetermined reference axis coincide with each other in the third reference coordinate system and the fourth reference coordinate system Step < / RTI >

The step of calculating the calibration target value may include calculating a length on the predetermined reference axis between the reference point in the third reference coordinate system and the reference point in the fourth reference coordinate system.

The navigation method may further include displaying at least one of the angle of the angle, the rotation angle and the distance on the display.

According to another aspect of the present invention, there is provided a navigation device comprising:

Generating a first deformed 3D image for a non-fractured bone of a patient from a standard 3D image for a given bone, dividing the bone contained in the first deformed 3D image into two portions, An image processing unit for generating a second modified 3D image in comparison with the 2D image photographed for the second modified 3D image; A transformation relation calculation unit for extracting a transformation relation (C) between a first reference coordinate system set for the first partial bone included in the second modified 3D image and a second reference coordinate system set for the second partial bone; And setting a third reference coordinate system for the first partial bone included in the second modified 3D image, setting a fourth reference coordinate system for the second partial bone based on the extracted conversion relation (C) And a correction target value calculation unit for calculating a correction target value of the fractured bone based on a positional relationship between the third reference coordinate system and the fourth reference coordinate system.

A navigation device and method for fracture correction according to one embodiment of the present invention can reduce radiation exposure to a patient.

Further, the navigation apparatus and method for fracture correction according to an embodiment of the present invention can improve the accuracy of the fracture correction procedure.

However, effects that can be achieved by the navigation apparatus and method for correcting fractures according to an embodiment of the present invention are not limited to those mentioned above, and other effects not mentioned can be obtained from the following description. And will be apparent to one of ordinary skill in the art.

1 is an exemplary diagram illustrating an environment in which a navigation device according to an embodiment of the present invention is used.
2 is a flowchart illustrating a navigation method according to an embodiment of the present invention.
3 is a diagram for explaining a method of generating a first modified 3D image from a standard 3D image.
4 is a diagram for explaining a method of generating a second modified 3D image from the first modified 3D image.
5 is a diagram for explaining a method of calculating a transformation relation C between the first reference coordinate system of the first partial bone and the second reference coordinate system of the second partial bone included in the second modified 3D image.
6 is a diagram for explaining a method of setting a reference coordinate system on the first modified 3D image.
FIG. 7 is a diagram for explaining a process of calculating a corrected target value of a bone fractured in the second modified 3D image. FIG.
8 is an exemplary diagram showing the calibration target values displayed on the display.
9 is a block diagram showing a configuration of a navigation device according to an embodiment of the present invention.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is to be understood, however, that the intention is not to limit the invention to the specific embodiments, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In addition, numerals (e.g., first, second, etc.) used in the description of the present invention are merely an identifier for distinguishing one component from another.

Also, in this specification, when an element is referred to as being "connected" or "connected" with another element, the element may be directly connected or directly connected to the other element, It should be understood that, unless an opposite description is present, it may be connected or connected via another element in the middle.

In the present specification, a component represented by 'unit', 'module', or the like refers to a case where two or more components are combined into one component, or one component is divided into two or more ≪ / RTI > In addition, each of the components to be described below may additionally perform some or all of the functions of the other components in addition to the main functions of the component itself, and some of the main functions And may be performed entirely by components.

Hereinafter, exemplary embodiments according to the technical idea of the present invention will be described with reference to the drawings.

1 is an exemplary diagram illustrating an environment in which a navigation device 100 according to an embodiment of the present invention is used.

The navigation device 100 according to an embodiment of the present invention may be implemented by a general-purpose computer and may include a communication function, an image processing function, and a display function. In addition, the navigation device 100 may include a memory, a display, and a control unit, and the memory and the control unit may be implemented with at least one processor and may operate according to a program stored in the memory.

Navigation device 100 may receive a 2D image of patient 10 taken by 2D imaging device 200 from 2D imaging device 200 or otherwise from a separate server. The 2D imaging device 200 may include an x-ray device, but is not limited thereto, and other devices can be applied as long as a two-dimensional image of the patient 10 can be obtained.

The patient 10 is capable of imaging X-rays between the imaging area of the 2D imaging device 200, e.g., a c-arm type of x-ray device, i. E., Between the x-ray source 210 and the detector 250 have.

As described above, since the conventional navigation apparatus requires 3D photographing of the patient 10 before the procedure proceeds, there has been a problem that the increase of the treatment cost and the amount of the dose applied to the patient 10 are remarkable. In the embodiment, the standard 3D image is used to generate the patient-customized 3D image, so that the amount of exposure to the patient 10 can be greatly reduced.

2 is a flowchart illustrating a navigation method according to an embodiment of the present invention.

In step S210, the navigation device 100 generates a first deformed 3D image for a non-fractured bone of the patient 10 from a standard 3D image for a predetermined bone.

A standard 3D image is generated from a 2D image, a 3D image, etc., of bones of several people. For example, a standard 3D image may include a statistical shape model (SSM) of several bones. The first modified 3D image is a patient-customized 3D image of the unbroken bone of the patient 10, for example, when a fracture occurs in the bone of the right leg of the patient 10, Represents a patient-customized 3D image of bone.

3 is a view for explaining a method of generating a first modified 3D image from a standard 3D image 310. Referring to FIG. 3, a navigation device 100 includes a navigation device 100 for displaying a 2D image of an unfractured bone of a patient 10 The standard 3D image 310 can be modified by matching the standard 3D image 310 of the standard bone with the standard 3D image 310 of the standard bone. Specifically, the navigation device 100 matches each of the plurality of 2D images 330 of the patient 10 to a standard 3D image 310, projects the standard 3D image 310 in a matched state, The shape of the bone of the standard 3D image 310 may be modified such that the 2D image of the patient 10 corresponds to the 2D image 330 of the patient 10. For example, a 2D image 330 of any one of the patients 10 may be matched to a standard 3D image 310 viewed from a specific direction, and a bone of a virtual 2D image projected from the particular direction may be registered with the patient 10, Such that the voxel values of the standard 3D image 310 are the same as the bones of any one of the 2D images 330 of the 3D image.

In this way, the navigation device 100 transforms the standard 3D image 310 while matching each of the plurality of 2D images 330 with the standard 3D image 310, and then transforms the respective voxel values of the modified standard 3D image So that the first modified 3D image can be generated.

Next, in step S220, the navigation device 100 divides the bone included in the first deformed 3D image into two parts, and then compares it with the 2D image photographed against the fractured bone of the patient 10, Creates a transformed 3D image.

The first variant 3D image is a patient customized 3D image of the unbroken bone of the patient 10 and is therefore modified to produce a second variant 3D image which is a patient customized 3D image of the fractured bone of the patient 10 .

4 is a diagram for explaining a method of generating a second modified 3D image from the first modified 3D image 410. The navigation device 100 firstly divides the bones included in the first modified 3D image 410 into first The partial bone 412 and the second partial bone 414 are divided. Next, the 2D image 420 imaged with respect to the fractured bone of the patient 10 is corrected (corrected) by changing the position and / or degree of rotation of the second partial bone 414 with respect to the first partial bone 412 do. When a matching value satisfying a predetermined criterion is derived while the position and / or degree of rotation of the second partial bone 414 is derived, the navigation device 100 converts the first deformed 3D image of the corresponding state into the second deformed 3D image .

In step S230, the navigation device 100 extracts a conversion relationship (C) between a first reference coordinate system set for the first partial bone included in the second modified 3D image and a second reference coordinate system set for the second partial bone do. Each of the first reference coordinate system and the second reference coordinate system may be arbitrarily set for the first partial bone and the second partial bone. The navigation apparatus 100 can extract the transformation relation C using the first feature points extracted from the first transformed 3D image and the second feature points extracted from the second transformed 3D image.

5, a reference coordinate system (a) is set for the bones included in the first modified 3D image 410, a first partial bone 512 included in the second modified 3D image 510, And a second reference coordinate system c is set for the second partial bone 514 included in the second modified 3D image 510. In this case, The navigation device 100 extracts the first feature points 412 from the bones of the first modified 3D image 410 and extracts the first partial bone 512 and the second partial bone 512 included in the second transformed 3D image 510, And extracts the second feature points 515 with respect to the second feature point 514. Since the first modified 3D image 410 and the second modified 3D image 510 are both patient-customized images, the first feature points 412 and the second feature points 515 may correspond to each other. In other words, a part of the first feature point 412 extracted from the bone of the first modified 3D image 410 corresponds to the second feature point 515 extracted from the first partial bone 512, Between the reference coordinate system a and the first reference coordinate system b using the coordinates of the first feature point 412 based on the first reference coordinate system b and the coordinates of the second feature point 515 based on the first reference coordinate system b, The conversion relation (A) can be calculated. It is obvious to those skilled in the art to calculate the transformation relation (or transformation matrix) between two reference coordinate systems by using coordinate information of points corresponding to each other in two images having different reference coordinate systems, and a detailed description thereof will be omitted.

Likewise, since a part of the first feature point 412 extracted from the bone of the first modified 3D image 410 corresponds to the second feature point 515 extracted from the second partial bone 514, the reference coordinate system (a) (A) and the second reference coordinate system (c) by using the coordinates of the first feature point 412 as a reference and the coordinates of the second feature point 515 based on the second reference coordinate system c as the reference, The relationship (B) can be calculated. Thereafter, the navigation device 100 can calculate the conversion relationship C between the first reference coordinate system b and the second reference coordinate system c through the conversion relationship A and the conversion relation B.

Referring again to FIG. 2, in step S240, the navigation device 100 sets a third reference coordinate system for the first partial bone included in the second transformed 3D image, and based on the extracted transformation relation C, Set a fourth reference coordinate system for the two partial bones.

6, it is possible to arbitrarily set a reference coordinate system in which the reference axis (for example, the z-axis) is parallel to the central axis 415 of the bone of the first deformed 3D image 410. The navigation apparatus 100 The reference coordinate system set for the bones of the first modified 3D image 410 may be set to a third reference coordinate system for the first partial bone of the second modified 3D image. According to an embodiment, a third reference coordinate system having a reference axis parallel to the central axis of the first partial bone of the second modified 3D image may be set for the first partial bone. The central axis for the bone can be identified in a variety of ways within the scope of what is known in the art.

Since the navigation apparatus 100 knows the transformation relation C between the first reference coordinate system and the second reference coordinate system, the navigation apparatus 100 applies the transformation relation C to the third reference coordinate system to obtain the fourth reference coordinate system for the second partial bone Can be set.

In step S250, the navigation device 100 calculates the corrected target value of the fractured bone based on the positional relationship between the third reference coordinate system and the fourth reference coordinate system.

The calibration target value may include, for example, at least one of an angulation angle, a rotation angle and a length between the first partial bone and the second partial bone of the second modified 3D image, The calculation method will be described with reference to FIG.

FIG. 7 shows a process of setting a reference coordinate system d with respect to bones of the first deformed 3D image 410 (1). As described above, a reference coordinate system d having a reference axis parallel to the central axis of the bone of the first modified 3D image 410 may be set.

Next, a reference coordinate system identical to the reference coordinate system d set for the bone of the first modified 3D image 410 is set to the third reference coordinate system e of the first partial bone 512 of the second modified 3D image 410 , The fourth reference coordinate system f of the second partial bone 514 is set based on the transformation relation C (2). The reference axis of the third reference frame (e) may be parallel to the central axis of the first partial bone 512.

Next, the reference axis (e.g., z axis) of the third reference coordinate system e and the reference axis (e.g., the z axis) of the fourth reference coordinate system f are aligned in the same direction The second partial bones 514 are moved (i.e., ④ and ④) so that the direction vectors are the same. The angle at which the second partial bones 514 rotate while the reference axis of the third reference coordinate system e and the reference axis of the fourth reference coordinate system f are aligned may be an angle of incidence.

Next, the second partial bones 514 are rotated (5) so that the axes other than the reference axes of the third reference coordinate system (e) and the reference axes of the fourth reference coordinate system (f) coincide with each other. For example, the second partial bones 514 may be rotated about the reference axis such that the axes other than the reference axes of the third reference coordinate system (e) and the axes other than the reference axes of the fourth reference coordinate system (f) . The angle at which the second partial bones 514 are rotated while the axes other than the reference axes of the third reference coordinate system e and the reference axes of the fourth reference coordinate system f coincide may be rotation angles .

Next, a reference point in the third reference coordinate system e (for example, any feature point included in the first partial bone 512) and a reference point in the fourth reference coordinate system f (for example, (Any feature point included in the bone 514) on the predetermined reference axis. For example, when the reference point in the third reference coordinate system e is the origin and the reference point in the fourth reference coordinate system f is the origin, the origin of the third reference coordinate system e and the origin of the fourth reference coordinate system f, The distance on the predetermined reference axis between the origin points of the reference points can be calculated.

Next, the navigation device 100 can display at least one of the calculated calibration target values on the display 800, as shown in FIG. 8, so that the medical staff can easily know how to calibrate the partial bone for the fracture procedure .

9 is a block diagram showing a configuration of a navigation device 100 according to an embodiment of the present invention.

9, the navigation device 100 according to an embodiment of the present invention may include a memory 910, an image processing unit 930, a conversion relation calculation unit 950, and a calibration target value calculation unit 970 have. The memory 910, the image processing unit 930, the conversion relation calculating unit 950 and the calibration target value calculating unit 970 may be implemented with at least one processor and may operate according to a program stored in the memory 910 .

The memory 910 may store standard 3D images generated from images of bones of various people and the like. In addition, the memory 910 may store 2D images taken of the fractured and unfractured bones of the patient 10.

The image processing unit 930 generates a first deformed 3D image for a non-fractured bone of the patient 10 from a standard 3D image for a predetermined bone, and divides the bone included in the first deformed 3D image into two parts And then compares it with the 2D image taken against the fractured bone of the patient 10 to produce a second modified 3D image.

The conversion relation calculating unit 950 calculates a conversion relationship (C) between a first reference coordinate system set for the first partial bone included in the second modified 3D image and a second reference coordinate system set for the second partial bone.

The calibration target value calculation unit 970 sets a third reference coordinate system for the first partial bone included in the second modified 3D image and calculates a fourth reference coordinate system for the second partial bone based on the extracted conversion relation (C) And a correction target value of the fractured bone is calculated based on the positional relationship between the third reference coordinate system and the fourth reference coordinate system.

The calibration target value calculator 970 can display the calculated calibration target value through display.

Meanwhile, the embodiments of the present invention described above can be written in a program that can be executed in a computer, and the created program can be stored in a medium.

The medium may include, but is not limited to, storage media such as magnetic storage media (e.g., ROM, floppy disks, hard disks, etc.), optical reading media (e.g., CD ROMs,

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. You will understand. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

100: Navigation device
200: 2D imaging device
910: Memory
930:
950: conversion relation calculating unit
970: Calibration target value calculation unit

Claims (10)

Generating a first modified 3D image for a non-fractured bone of a patient from a standard 3D image for a given bone;
Dividing a bone included in the first modified 3D image into two parts and then creating a second modified 3D image by comparing the extracted bone with a 2D image photographed against a fractured bone of a patient;
Extracting a transformation relationship (C) between a first reference coordinate system set for the first partial bone included in the second modified 3D image and a second reference coordinate system set for the second partial bone;
Setting a third reference coordinate system for the first partial bone included in the second modified 3D image and setting a fourth reference coordinate system for the second partial bone based on the extracted transformation relation (C); And
And calculating a correction target value of the fractured bone based on a positional relationship between the third reference coordinate system and the fourth reference coordinate system.
The method according to claim 1,
Wherein the generating the first variant 3D image comprises:
Matching each of the plurality of 2D images of the patient's unbroken bone to the standard 3D image;
Transforming the standard 3D image so that a virtual 2D image generated from the standard 3D image corresponds to each of the plurality of 2D images; And
And generating the first modified 3D image by correcting each of the voxel values of the modified standard 3D image through an extrapolation method.
The method according to claim 1,
Wherein the step of generating the second modified 3D image comprises:
And matching the 2D image photographed with respect to the fractured bone of the patient while deforming at least one of the position and degree of rotation of the second partial bone with respect to the first partial bone of the first deformed 3D image .
The method according to claim 1,
The step of extracting the transformation relation (C)
Extracting first feature points from bones included in the first modified 3D image;
Extracting second feature points from the first partial bone and the second partial bone included in the second modified 3D image;
(A) between the reference coordinate system set for the bones included in the first deformed 3D image and the first reference coordinate system by mapping the first feature points and the second feature points to the first deformed 3D image, Calculating a transformation relation (B) between the reference coordinate system set for the bone and the second reference coordinate system; And
(C) using the conversion relation (A) and the conversion relation (B).
The method according to claim 1,
Wherein the step of setting the third reference coordinate system comprises:
And setting a third reference coordinate system in which a predetermined reference axis is parallel to the central axis of the first partial bone included in the second modified 3D image.
The method according to claim 1,
The step of calculating the calibration target value includes:
Calculating an angulation angle when the second partial bone is moved so that a predetermined reference axis of the third reference coordinate system and a predetermined reference axis of the fourth reference coordinate system align in the same direction . ≪ / RTI >
The method according to claim 6,
The step of calculating the calibration target value includes:
And calculating a rotation angle when the second partial bone is rotated such that axes other than the predetermined reference axis coincide with each other in the third reference coordinate system and the fourth reference coordinate system, Way.
8. The method of claim 7,
The step of calculating the calibration target value includes:
And calculating a length on the predetermined reference axis between the reference point in the third reference coordinate system and the reference point in the fourth reference coordinate system.
9. The method of claim 8,
The navigation method includes:
And displaying at least one of the angle of angulation, the rotation angle and the distance on the display.
Generating a first deformed 3D image for a non-fractured bone of a patient from a standard 3D image for a given bone, dividing the bone contained in the first deformed 3D image into two portions, An image processing unit for generating a second modified 3D image in comparison with the 2D image photographed for the second modified 3D image;
A transformation relation calculation unit for extracting a transformation relation (C) between a first reference coordinate system set for the first partial bone included in the second modified 3D image and a second reference coordinate system set for the second partial bone; And
Setting a third reference coordinate system for the first partial bone included in the second modified 3D image, setting a fourth reference coordinate system for the second partial bone based on the extracted conversion relation (C) And a correction target value calculation unit for calculating a correction target value of the fractured bone based on a positional relationship between the reference coordinate system and the fourth reference coordinate system.

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