KR20170088742A - Workstation, medical imaging apparatus comprising the same and control method for the same - Google Patents

Abstract

A workstation, a medical imaging apparatus including the same, and a control method thereof are disclosed. The medical imaging apparatus according to an aspect of the present invention includes: an X-ray source for irradiating an X-ray; an X-ray detector for detecting the X-ray irradiated from the X-ray source and acquiring raw data; and an image processing unit for determining a motion parameter indicating the motion of at least one of an object, the X-ray source, and the X-ray detector from a medical image restored based on the acquired raw data, and restoring the medical image in which the motion of the object is compensated based on the virtual trajectory of the X-ray source. Accordingly, the present invention can more precisely acquire the medical image.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical imaging apparatus including a workstation and a control method thereof,

The disclosed embodiments relate to a workstation, a medical imaging device including the same, and a method of controlling the medical imaging device.

In general, a medical imaging device is a device that acquires a medical image by imaging the inside of a target object, and makes the acquired medical image available for diagnosis. Specifically, the medical imaging device captures and processes structural details within the body, internal tissue, and fluid flow, and displays them to the user. A user such as a doctor can diagnose a health condition and a disease of a patient by using a medical image outputted from a medical imaging apparatus. Therefore, the more accurate the medical image, the more accurately the patient can be determined. Therefore, in recent years, research on a method of acquiring a medical image more precisely is underway.

A medical imaging apparatus according to one aspect, comprising: an X-ray source for irradiating an X-ray; An X-ray detector for detecting X-rays irradiated from the X-ray source and acquiring raw data; And a motion parameter indicating motion of at least one of the object, the x-ray source, and the x-ray detector from the medical image reconstructed based on the acquired raw data, And restoring the medical image in which the motion of the object is compensated based on the virtual trajectory of the object.

In addition, the image processor may determine a motion parameter value at at least one scan time or scan time by applying an image quality metric process to the medical image restored based on the acquired raw data.

In addition, the image processing unit may set at least one control point, determine a motion parameter value at the set control point, and approximate from the determined motion parameter value to generate a graph for each motion parameter .

The image processing unit may set the motion parameter as a variable and apply the image quality metric process in which at least one of an entropy value, a sharpness value, and a gradient value is set as a result value, The motion parameter value can be determined at the scan time or the scan time.

The image processing unit may calculate a motion parameter value at each scan time or scan time using the generated graph and generate a virtual trajectory of the X-ray reflecting movement of the object based on the calculated motion parameter value can do.

The image processing unit may perform a weighting process on the projection data derived from the row data based on the distance between the X-ray source and the X-ray detector on the virtual trajectory of the generated X-ray source .

The image processing unit may perform a filtering process on the projection data derived from the row data based on the tangential direction of the virtual trajectory of the generated X-ray source.

In addition, the image processing unit may perform a back projection process based on the FDK algorithm on the projection data derived from the row data to restore the medical image compensated for the motion of the object.

In addition, the motion parameter may include at least one of a motion of the object itself, and a relative motion of the object reflecting movement of the at least one of the X-ray source and the X-ray detector.

In addition, the motion parameter may further include a parameter indicating a distance between the X-ray source and the X-ray detector.

In addition, the image processing unit can identify the marker on the partial medical image by comparing the pre-stored template partial medical image and the partial medical image obtained by irradiating the X-ray to the object to which the marker is attached.

In addition, the image processor may determine an initial motion parameter value by tracking the position of the marker identified on the partial medical image, and restore the medical image in which the motion of the object is compensated based on the determined initial motion parameter value .

A workstation according to one side controls a operation of an X-ray source and an X-ray detector so as to obtain raw data according to the input scan command; And generating a first medical image from the obtained raw data, generating a virtual trajectory of the X-ray source based on the motion parameter determined from the first medical image, and moving the object based on the virtual trajectory of the X- And an image processing unit for restoring the compensated second medical image.

In addition, the image processor may determine a motion parameter value at at least one scan time or scan time by applying an image quality metric process to the first medical image restored based on the acquired raw data.

In addition, the image processing unit may set at least one control point, determine a motion parameter value at the set control point, and approximate from the determined motion parameter value to generate a graph for each motion parameter .

The image processing unit may set the motion parameter as a variable, apply the image quality metric process in which at least one of an entropy value, a sharpness value, and a gradient value is set as a result value, Can be determined.

The image processing unit may calculate a motion parameter value at each scan time or scan time using the generated graph and generate a virtual trajectory of the X-ray reflecting movement of the object based on the calculated motion parameter value can do.

The image processing unit may perform the weighting process on the projection data derived from the row data based on the distance between the X-ray source and the X-ray detector on the virtual trajectory of the generated X-ray source.

The image processing unit may perform a weighting process on the projection data derived from the row data using a parameter indicating a distance between the X-ray source and the X-ray detector among the determined motion parameters.

The image processing unit may perform a filtering process on the projection data derived from the row data based on the tangential direction of the virtual trajectory of the generated X-ray source.

A method of controlling a medical imaging apparatus according to one aspect includes the steps of: detecting X-rays irradiated from the X-ray source to obtain raw data; Determining a motion parameter indicating a motion of the object from the medical image restored based on the acquired raw data; And reconstructing a medical image in which motion of the object is compensated based on the virtual trajectory of the X-ray source generated based on the determined motion parameter.

In addition, the determining step may determine a motion parameter value at at least one scan time or a scan time by applying an image quality metric process to the medical image restored based on the acquired raw data.

The determining step may include setting at least one control point, determining a motion parameter value at the set at least one control point, and approximating the determined motion parameter value to generate a graph for each motion parameter As shown in FIG.

In addition, the determining may include calculating a motion parameter value at each scan time or scan time using the generated graph, and calculating a virtual trajectory of the X-ray reflecting movement of the object based on the calculated motion parameter value And a step of generating the generated data.

A control method of a workstation according to one side includes: receiving a scan command related to a target from a user; Controlling an operation of an X-ray source and an X-ray detector so as to obtain raw data according to the input scan command; And generating a first medical image from the acquired raw data, generating a virtual trajectory of the x-ray source based on the motion parameter determined from the first medical image, and compensating for motion of the object based on the virtual trajectory of the x- And reconstructing a second medical image.

The reconstructing may include determining a motion parameter value at at least one scan time or scan time by applying an image quality metric process to the first medical image reconstructed based on the acquired raw data .

The restoring may include setting at least one control point, determining a motion parameter value at the set at least one control point, and approximating the determined motion parameter value to generate a graph for each motion parameter . ≪ / RTI >

The restoring may include calculating a motion parameter value at each scan time or scan time using the generated graph and calculating a virtual trajectory of the X-ray reflecting the movement of the object based on the calculated motion parameter value And a step of generating the data.

Figs. 1A and 1B are views schematically showing an appearance of a medical imaging apparatus as an example of a medical imaging apparatus. Fig.
2 is a view schematically showing a table on which an object according to one embodiment is placed.
FIGS. 3 and 4 are views schematically showing a relationship between an X-ray source and an X-ray detector according to another embodiment, and a relationship between an object positioned between the X-ray source and the X-ray detector
FIG. 5 is a view for explaining a case where a scan is performed through a spiral scan method according to an embodiment.
6A and 6B are diagrams showing a trajectory in which an X-ray source according to another embodiment rotates.
7A and 7B are views schematically showing control block diagrams of a medical imaging apparatus according to different embodiments.
8A and 8B are graphs illustrating motion parameters during a scan time according to an exemplary embodiment.
FIGS. 9A and 9B are diagrams showing a virtual trajectory of an X-ray source generated by reflecting movement of an object according to different embodiments.
10 is a diagram showing a virtual trajectory of an x-ray source through an orthogonal coordinate system according to an embodiment.
FIGS. 11A, 11B, and 11C are diagrams for explaining a case where a filtering direction is set in a tangential direction of an X-ray source according to another embodiment.
12 is a diagram for explaining a template partial medical image according to an embodiment and an initial motion parameter value at a reference point.
13A is a view schematically showing a partial medical image including a subject and a marker according to an embodiment.
FIG. 13B is a view schematically showing a masked partial medical image according to an embodiment.
14 is a graph illustrating an initial motion parameter value generated using an initial motion parameter value at a reference point according to an exemplary embodiment.
FIG. 15 is a diagram for explaining an operational flow for a medical imaging apparatus for generating a second medical image based on a motion parameter value according to an embodiment.
16 is a view for explaining an operation flow of a medical imaging apparatus for generating a second medical image based on an initial motion parameter value determined using a partial medical image according to an embodiment.
FIG. 17 is a diagram for explaining an operation flow of a medical imaging apparatus for generating a medical image in which motion of an object is compensated by irradiating an X-ray according to an embodiment.

A medical imaging device means a device for acquiring a medical image that images the inside of a target object. Here, the object ob may be a living body of a human being or an animal, or a living tissue such as blood vessels, bones, muscles and the like, but is not limited thereto, and may include various types of signals, such as phantom, Can be any object as long as its internal structure can be imaged.

The medical imaging apparatus described below includes all of the apparatus for acquiring the medical image that images the inside of the object. For example, the medical imaging device includes all devices capable of acquiring medical images related to the interior of a target object such as a magnetic resonance imaging (MRI) device and an ultrasound imaging device using an ultrasonic probe. Medical imaging devices also include all tomographic imaging devices such as Computed Tomography (CT) imaging devices, OCT (Optical Coherence Tomography), and PET (positron emission tomography) -CT imaging devices,

Hereinafter, one example of a medical imaging apparatus will be described as an example of a computer tomography imaging apparatus, but the embodiments described below are not limited thereto, and any apparatuses capable of acquiring medical images can be applied.

FIGS. 1A and 1B are views schematically showing an appearance of a medical imaging apparatus as an example of a medical imaging apparatus, and FIG. 2 is a view schematically showing a table on which an object is placed according to an embodiment. 3 and 4 are views schematically showing a relationship between an X-ray source and an X-ray detector according to another embodiment, and a relation between an object positioned between the X-ray source and the X-ray detector. FIG. 5 is a view for explaining a case where a scan is performed through a spiral scan method according to an embodiment, and FIGS. 6A and 6B are views showing a trajectory in which an X-ray source according to another embodiment is rotated. 7A and 7B are diagrams showing control block diagrams of a medical imaging apparatus according to different embodiments. Hereinafter, the description will be described together to prevent duplication of description.

Referring to FIG. 1A, a medical imaging apparatus 100 includes a housing 101 on which irradiation and detection of an X-ray are performed, and a table 190 for moving the object.

Inside the housing 101, a cylindrical gantry 102 may be provided. Inside the gantry 102, an x-ray source 110 for irradiating x-rays and an x-ray detector 120 for detecting x-rays may be provided to face each other.

The object ob may be positioned between the x-ray source 110 and the x-ray detector 120. At this time, the object ob may be positioned on the table 190, and the table 190 may enter the gantry 102 (D1 direction).

1B, the medical imaging device 100 may include a workstation 200 that performs operation control, image restoration, etc., of the medical imaging device 100. Here, the workstation 200 includes a host In the following description, the apparatus for controlling the overall operation of the medical imaging apparatus 100 will be referred to as a workstation 200 for the sake of convenience. A detailed description of the workstation 200 will be given later. .

2, the object ob lies on the table 190 and is transferred into the gantry 102. When the scan region of the object ob, that is, the region of interest is located at the scan position, The X-ray source 110 and the X-ray detector 120 rotate and scan the X-ray to detect the object and scan the object ob. Accordingly, the medical imaging apparatus 100 can acquire the medical image based on the scan result.

The gantry 102 may include a rotating frame (not shown), an x-ray source 110, an x-ray detector 120, a data acquisition circuit (Fig. 5,116) and a data transmitter (Fig.

The X-ray source 110 refers to a device for generating an X-ray to irradiate an object (ob). The X-ray source 110 may be provided with a filtering unit for filtering X-rays to be irradiated.

The x-ray source 110 may examine x-rays in various forms. For example, the x-ray source 110 may not irradiate an x-ray in the form of a three-dimensional cone-beam or irradiate an x-ray in the form of a two-dimensional fan-beam . Hereinafter, the case of irradiating X-rays in the form of a three-dimensional cone beam will be described, but the embodiments to be described later are not limited thereto.

The X-ray detector 120 means an apparatus for detecting X-rays transmitted through the object ob. At this time, the X-ray detector 120 may be provided on the opposite side of the X-ray source 100. When the table 190 enters the gantry 102, the object ob may be positioned between the x-ray source 110 and the x-ray detector 120. Then, the x-ray irradiated from the x-ray source 110 can be detected through the x-ray detector 120 through the object ob.

For example, the X-ray detector 120 can detect an X-ray irradiated from the X-ray source 110 and generate an electric signal corresponding to the intensity of the detected X-ray. The X-ray detector 120 may be implemented in various forms. For example, the X-ray detector 120 may be implemented in a flat form or in a curved form.

The x-ray source 110 and the x-ray detector 120 may be provided on opposite sides as shown in Figs. 3 and 4. The x-ray source 110 and the x- And the raw data can be obtained by performing the irradiation and detection of the X-ray while rotating the X-ray tube. 3 and 4, when the head part c of the object is to be scanned, the x-ray source 110 and the x-ray detector 120 rotate 360 degrees about the head part c, The raw data can be acquired through the irradiation and detection of the X-ray.

The medical imaging apparatus 100 may derive projection data by performing a pre-processing process on the raw data. A detailed description thereof will be given later.

The object ob is laid in the table 190 and transferred to the inside of the gantry 102. When the scan region of the object ob is located at the scan position, The X-ray is scanned and detected to scan the object ob.

The scanning of the object ob can be performed in a state where the table 190 is fixed, for example, an axial scan method. In one embodiment, when the table 190 in which the object ob is laid is transported into the gantry 102 at a constant speed, the scan region of the object ob, that is, the region of interest may be located at the scan position. Then, the table 190 is stopped and the X-ray source 110 and the X-ray detector 120 inside the gantry 102 rotate and scan the X-ray to scan the object ob.

On the other hand, the scanning method of the object ob is not limited to the example described above. The scan of the object ob may be performed in a state in which the table 190 moves in a specific axial direction, for example, in a helical scan manner, or in a state in which the table 190 is fixed, And the X-ray detector 120 are rotated while moving in a specific axial direction.

5, either the gantry 102 or the table 190 equipped with the x-ray source 110 and the x-ray detector 120 can move in the direction of the axis D1 during scanning.

For example, while the x-ray source 110 and the x-ray detector 120 are rotated, the table 190 can move at a constant speed in the direction of the axis D1. At this time, scanning of the object ob can be performed by irradiating and detecting the X-ray while rotating the X-ray source 110 and the X-ray detector 120. As the table 190 is scanned while moving, the x-ray source 110 and the x-ray detector 120 can perform scanning while rotating the object ob spirally, as shown in Fig. In one embodiment, the scan time may be set between about 250 ms and 1 second, and may be set differently depending on the stability of the medical imaging apparatus 100, for example.

However, since the scan is performed while the table 190 is moving, movement of the x-ray source 110, the x-ray detector 120, and the object ob can be generated by various factors. For example, if the floor where the medical imaging device 100 is located is not flat, the medical imaging device 100, such as the table 190, or the gantry 102, may experience motion during movement.

Here, the motion of the components of the medical imaging apparatus 100 means a motion that deviates from a predetermined motion according to a scan method. The distance between the x-ray source 110 and the object ob and the distance between the x-ray detector 120 and the object ob can be changed as well as the distance between the x-ray source 110 and the x- It is possible to cause artifacts in the medical image.

As another example, in a state where the table 190 is fixed, the gantry 102 provided with the x-ray source 110 and the x-ray detector 120 can be moved. Accordingly, the X-ray source 110 and the X-ray detector 120 perform scanning while moving in the direction of the axis D1, so that the scanning can be performed while rotating in a spiral manner as shown in FIG.

For example, in the case of a mobile computer tomographic imaging apparatus, which is mainly used in an operating room or the like, as one example of the medical imaging apparatus 100, a spiral scanning method can be mainly used. However, the spiral scan method may be less stable due to various factors such as the flatness of the floor where the medical imaging apparatus 100 is located, external pressure, and the like.

Accordingly, the probability that the distance between the X-ray source 110 and the X-ray detector 120 changes is high and the probability that the distance between the X-ray source 110 and the object and the distance between the X-ray detector 120 and the object are also changed. Therefore, such a change causes an occurrence of an artifact in a medical image, and compensation is therefore required. A detailed description thereof will be given later.

The medical imaging apparatus 100 according to the embodiment can perform scan through various scan methods described above to acquire row data, and there is no limitation.

For example, referring to FIG. 6A, the medical imaging apparatus 100 can acquire a medical image relating to a head part c of a target object by irradiating an X-ray to the head part c of the object through the X-ray source 110 have. At this time, the X-ray source 110 and the X-ray detector 120 are rotated 360 degrees in accordance with the locus L1 in a state of facing each other and acquire row data at various views, that is, at various scan points or scan angles . Here, not only the head portion of the object can be set to the region of interest in the medical image, but other regions can be set, and there is no limitation.

6B, the medical imaging apparatus 100 may be configured to rotate the X-ray source 110 spirally and irradiate an X-ray to the head part c of the object, thereby obtaining a medical image about the head part c of the object Can be obtained. The x-ray source 110 and the x-ray detector 120 may acquire row data at various scan points or scan angles while rotating along the locus L3.

At this time, a method of restoring the medical image from the raw data acquired according to the locus L1 shown in Fig. 6A and a method of restoring the medical image from the raw data acquired according to the locus L3 shown in Fig. Or may be different.

For example, in order to restore the medical image from the raw data acquired according to the locus L3 shown in FIG. 6B, it is necessary to perform known image processing such as 360 linear interpolation, 360 linear interpolation, Processes may be additionally required, but are not limited thereto. Hereinafter, a control block diagram of the medical imaging apparatus 100 will be described.

7A and 7B are block diagrams showing control blocks of a medical imaging apparatus according to different embodiments.

7A, the medical imaging apparatus 100 includes a gantry 102, an x-ray source 110, a data acquisition circuit 116, a data transmission unit 117, an x-ray detector 120, a user interface unit 130, An image processing unit 140, a control unit 150, a storage unit 160, a communication unit 170, and a table 190.

At least one of the image processing unit 140, the control unit 150, the storage unit 160, and the communication unit 170 is integrated into a system on chip (SOC) built in the medical imaging apparatus 100 . However, since only one system-on-chip is built in the medical imaging apparatus 100, the system-on-chip may not be integrated into one system-on-chip. Since the description of the x-ray source 110, the x-ray detector 120, and the table 190 has been described above, a detailed description thereof will be omitted.

The table 190 can move in a predetermined direction (e.g., at least one of x-axis direction, y-axis direction, and z-axis direction). Meanwhile, movement of the table 190 can be controlled through the control signal of the controller 150. [ A detailed description of the control unit 150 will be given later.

The data acquisition system (DAS) 116 is connected to the X-ray detector 120 in a wired or wireless manner to collect digital signals, that is, digital data generated from the X-ray detector 120. Here, the digital data may be transmitted to the image processing unit 150 through a data transmission unit 120 by wire or wirelessly. Here, the transmitted digital data is referred to as raw data.

The user interface unit 130 can receive various control commands related to the operation of the medical imaging apparatus 100 from a user and can provide various kinds of information. A detailed description related to the user interface unit 130 will be described later.

The image processing unit 140 may perform various processes for acquiring medical images. For example, the image processing unit 140 may be implemented through a graphics processor, and a graphics memory.

The image processing unit 140 may receive the row data and perform a pre-processing process. Here, the preprocessing process is a process necessary for acquiring projection data, for example, a process of correcting sensitivity non-uniformity between channels, a sharp decrease in signal intensity, or a process of correcting loss of a signal due to an X- , And various known processes required for obtaining projection data.

Here, the projection data may be a set of row data obtained at any one scan angle. That is, a set of raw data obtained at the same scan angle for all the channels is referred to as projection data.

The image processing unit 140 can generate a sinogram by acquiring projection data at all scan angles. That is, the set of projection data is referred to as a sinogram. For example, the sinogram may include projection data photographed at various scan angles from 0 to 360 degrees of rotation angle of the x-ray source 110. [

For example, the X-ray source 110 and the X-ray detector 120 may rotate 360 degrees in a state of facing each other to acquire row data at a scan time of 1440 view, that is, at a scan time of 1440 for a scan time of 250 ms . That is, row data for all directions are acquired at intervals of 0.25 ㅀ, and a reconstruction technique such as a back projection process or the like is performed for a sinogram corresponding to a set of projection data obtained by performing a preprocessing process The medical image can be generated. Here, the medical image may be a three-dimensional image.

For example, the image processing unit 140 can reconstruct a medical image of a target object using the obtained projection data. For example, the image processing unit 140 can apply a predetermined process to the projection data, and then apply a back projection process based on the FDK algorithm proposed by Feldkamp, Davis, and Kress (FDK) to generate a three-dimensional medical image have. Hereinafter, a method of reconstructing a medical image through a back projection based on the FDK algorithm will be described as an example of the reconstruction technique. However, the following embodiments are not limited thereto and other image reconstruction techniques may be applied.

The image processing unit 140 may generate a medical image from the projection data through a back projection process based on the FDK algorithm. At this time, the object can move during the irradiation of the X-ray, that is, during the scan. For example, the head of a user may have motion during a scan. Therefore, unless the motion of the target object is corrected, artifacts due to the motion are generated, and accurate medical images can not be provided.

Accordingly, in generating the medical image from the acquired sinogram, the image processing unit 140 according to the embodiment can calculate the motion parameters and generate the medical image compensated for the motion by reflecting the calculated motion parameters.

Here, the motion parameter means a parameter capable of indicating the degree of motion of the object through the coordinate system. Here, the coordinate system includes all kinds of coordinate systems as long as it can represent the movement of the object by the coordinates.

For example, when an orthogonal coordinate system that expresses coordinates with three axes (x axis, y axis, z axis) orthogonal to each other is used, the motion parameters are expressed by the angles and distances to the x axis, y axis, Can be expressed.

For example, the motion parameters may be composed of Rx (), Ry () Rz (), Tx, Ty, Tz 6 parameters. Where Ry (Φ) represents the angle at which the object moves in the y-axis, and Rz (θ) represents the angle at which the object moves in the z-axis. Also, Tx represents the distance the object moves in the x-axis, Ty represents the distance the object moves in the y-axis, and Tz represents the distance the object moves in the z-axis.

Meanwhile, as described above, components of the medical imaging apparatus 100 may be moved during scanning, and artifacts may be generated in the medical image. At this time, the motion parameters may include not only the motion of the object itself, but also the motion of the components of the medical imaging apparatus 100. Accordingly, the medical imaging apparatus 100 according to the embodiment can minimize the artifacts of the medical image through the motion parameters reflecting the motion of the object of the medical imaging apparatus 100 as well as the motion of the object.

For example, when a movement occurs in the x-ray source 110 at a specific scan time or a scan time, it is assumed that the x-ray source 110 has no movement, that is, If the movement of the object is reflected, movement of the X-ray source 110 can be reflected on the virtual trajectory.

In other words, when a component movement occurs in the medical imaging apparatus 100 at a specific scan time or a scan time, the movement of the components in the medical imaging apparatus 100 can be reflected relatively to the movement of the object. In one embodiment, when the x-ray source 110 is moved by + 1 cm in the x-axis, the movement of the x-ray source 110 may be reflected if the object is reflected by the -1 cm relative to the x-axis. Accordingly, if the position of the x-ray source 110 is moved by + 1 cm along the x-axis on the virtual trajectory in order to compensate for the movement of the object, the movement of the x-ray source 110 may be reflected on the virtual locus. The motion of the object described below includes not only the motion of the object itself, but also the relative motion of the object reflecting the motion change of the components of the medical imaging apparatus 100, The motion parameters include not only the motion of the object, but also the motion of the components within the medical imaging device 100.

In addition to the above six parameters, the motion parameter may further include a parameter T _sd indicating movement between the x-ray source 110 and the x-ray detector 120. When the distance between the X-ray source 110 and the X-ray detector 120 is changed, the magnification is changed at the time of back projection, and an artifact is generated in the restored medical image. Accordingly, the image processing unit 140 according to the embodiment can determine the motion parameters further including the T _SD indicating the distance between the x-ray source 110 and the x-ray detector 120, thereby making it possible to generate a clearer medical image.

The image processing unit 140 adjusts the back projection position based on the motion parameter in performing the back projection process, if the object can determine whether the object has moved at each scan time or the scan point, More accurate back projection is possible. Hereinafter, a method of calculating motion parameters will be described.

The image processing unit 140 may determine a motion parameter from a reconstructed medical image from the projection data. At this time, the image processing unit 140 may perform image restoration based on a predetermined initial motion parameter value. Here, the initial motion parameter value may be preset and stored in the graphic memory of the image processing unit 140 or the like. In one embodiment, since the initial motion of the object is generally small, all of the initial motion parameter values may be set to '0'. As will be described later, the image processing unit 130 can provide a medical image that compensates for the motion of the object by determining the motion parameter value and regenerating the medical image using the determined motion parameter value.

Hereinafter, for convenience of explanation, a medical image generated by applying a reconstruction technique based on a predetermined initial motion parameter value is referred to as a first medical image, a motion parameter value is determined, and a medical image Is referred to as a second medical image.

When the image processing unit 140 restores the first medical image through the back projection, the image quality of the restored first medical image becomes lower as the movement is larger. On the other hand, before the back projection process, a weighting process and a filtering process are performed, and a detailed description thereof will be described later.

The back projection process based on the FDK algorithm is an operation process of reconstructing the projection data in which the weighting process and the filtering process have been performed into a medical image, and is mainly used when acquiring a three-dimensional medical image.

In this case, the 3D medical image refers to an image obtained by volume rendering three-dimensional volume data generated based on a plurality of sectional images on the basis of a predetermined viewpoint. For example, the image processing unit 140 may map the projection data photographed at various angles and reconfigure into a three-dimensional medical image. At this time, the reference position of the back projection is mapped while being moved, and the value when the image is most neatly restored can be determined as the motion parameter value at the corresponding scan time.

For example, the image processor 140 performs mapping of the projection data acquired from 1440 views, and calculates a motion parameter value when the medical image reconstructed in three dimensions is the most neat, at the corresponding scan time or scan time Can be determined by the motion parameter value.

Accordingly, the image processing unit 140 may determine the motion parameter value when the medical image is most clean, as the motion parameter value indicating the motion of the object at the scan time or the scan time, while adjusting the motion parameter value.

The image processing unit 140 may evaluate the image quality while adjusting the motion parameter values for the restored first medical image, determine the optimal motion parameter values based on the evaluation results, and update the motion parameter values based on the evaluation results Thereby restoring the motion compensated second medical image.

For example, the image processing unit 140 may apply an image quality metric process to determine a motion parameter value at a scan time or a scan time based on a result value. Here, the image quality metric process means one of quantitative techniques for determining image quality of an image.

In one embodiment, the image processing unit 140 may apply an image quality metric process to determine a value obtained when the result value is the smallest as a motion parameter value at the corresponding scan time or scan point. Alternatively, the image processor 140 may apply the image quality metric technique to the restored first medical image, and determine a value when the result value satisfies a predetermined level as the motion parameter value at the scan time or the scan point. That is, when the result of applying the image-quality metric process to the first medical image becomes minimum or maximum, the image processing unit 140 determines that the motion artifact of the object is minimized, Can be determined by the motion parameter value.

At this time, the image processing unit 140 may set a variable as a motion parameter, set an object of a result value, and then apply an image quality metric process. Here, the variable may be set to six motion parameters, and there is no limitation such that it may be set to seven motion parameters.

For example, the image processor 140 applies an image quality metric process by setting an entropy to a result value, and then outputs the motion parameter value when the resultant value, that is, the entropy value becomes the minimum, to the motion parameter value . In other words, the image processing unit 140 can determine the motion parameter value when the entropy becomes the smallest as the motion parameter value at the corresponding scan time.

As another example, the image processing unit 140 may set the degree of sharpness or gradient of the edge area of an object displayed in the first medical image as a target of a result value, The motion parameter value at which the result value reaches the maximum value may be determined as the motion parameter value at the corresponding scan time or scan point.

On the other hand, since the motion of the object changes continuously and varies instantaneously, the motion parameter value of the object may be changed by the scan time or the scan point. Therefore, in order to restore a more accurate image, it is necessary to determine the motion parameter value at each scan time or scan time, but there is a disadvantage that the calculation is increased.

Accordingly, the image processing unit 140 according to the embodiment may determine the motion parameter values at all scan times, but it is also possible to set one or more control points by dividing the scan time into equal intervals and set the motion parameter values at the set control points You can decide. Then, the image processing unit 140 can generate a graph of the motion parameter value according to the scan time, by moving the motion parameter value at the control point to the line. Here, the control point refers to a specific time point or a specific scan point among the scan points in the scan time.

For example, the image processing unit 140 sets N (N > = 1) control points for the entire scan time or the entire scan time, determines a motion parameter value at each control point, You can then set the graph. Accordingly, the image processing unit 140 determines a parameter value corresponding to each scan time or scan time from the graph, and adjusts a back projection position based on the parameter value, thereby restoring a more accurate image.

The image processor 140 repeatedly performs the motion parameter value determination at a specific point and point and replaces or updates the initial motion parameter value with the determined motion parameter value to restore a more accurate image . Accordingly, the medical imaging apparatus 100 according to the embodiment can detect the motion of the object in the medical image without needing to grasp the motion of the object through a separate device, and then, based on the motion, Can be provided.

8A and 8B are graphs illustrating motion parameters during a scan time according to an exemplary embodiment. 8A and 8B, the image processing unit 1400 sets four control points (C1, C2, C3, and C4), applies an image quality metric process, and determines a motion parameter value at each control point . Then, the image processing unit 1400 determines six motion parameter values at each control point, and approximates them based on the motion parameter values, thereby generating a graph as shown in FIGS. 8A and 8B.

In other words, the image processing unit 140 may determine only the motion parameter values corresponding to the specific time in the entire scan time through the image quality metric process, and then approximate them based on the image quality metric process to generate a graph. Then, the image processing unit 140 can calculate a motion parameter value at each scan time or scan time from the graph, and can generate a more accurate second medical image based on the calculation.

On the other hand, as the number of control points increases, the accuracy of the graph increases. At this time, the number of control points and the interval between control points can be preset. For example, the number of control points may be preset to a specific number, or may be determined to be proportional to the scan time or number of views. In addition, the interval between the control points can be set at equal intervals according to the number of scan points or the scan time. Data relating to the setting of the control point is stored in the graphic memory, and the image processing unit 140 can set at least one of the number of the control points and the interval between the control points using the data stored in the graphic memory.

As another example, the number of control points and the interval between control points can be set directly by the user. In one embodiment, the user can set at least one of the number and the interval of the control points through the user interface unit 130. [ When receiving information on at least one of the number and interval of control points set by the user from the user interface unit 130, the image processing unit 140 determines a motion parameter value at the corresponding control point based on the received information, By generating a graph approximated based on the parameter values, a second medical image can be generated using the generated graph.

Accordingly, the medical imaging device 100 according to the embodiment allows the user to directly set the control point according to the priority of the medical image and the restoration speed. The degree of freedom of the user can be increased. Hereinafter, a case will be described in which a second medical image that compensates for motion of the object is generated based on the motion parameter value.

For example, as a result of judging through the motion parameter value, it can be seen that the object moves + 1 cm in the x axis at a specific scan time or scan time. In order to compensate the motion of the object, if the position of the x-ray source 110 is moved by -1 cm along the x-axis at a specific scan time or scan time, the movement of the object may be relatively compensated.

At this time, the movement of the object may be caused by at least one of movement of the object itself and movement of the components of the medical imaging apparatus 100 at a specific scan time or scan time.

Accordingly, when it is determined through the motion parameter value that the object is moved by +1 cm in the x-axis at a specific scan time or scan time, the object itself moves by +1 cm or the x-ray source 110 moves by -1 cm . Alternatively, the object itself may move by + 2 cm and the x-ray source 110 may move -1 cm. At this time, it is not necessary to express how much of the object and the x-ray source 110 have moved on the virtual trajectory, and all of the movement of the object and the x-ray source 110 may be reflected. In this case, if the position of the x-ray source 110 on the virtual locus is shifted by -1 cm on the x-axis at a specific scan time or scan time to compensate for the movement of the object, the movement of the object itself and the relative movement of the object Can be compensated.

The image processing unit 140 may generate a virtual trajectory of the x-ray source 110 based on the motion parameter values. The virtual trajectory of the X-ray source 110 means a trajectory generated by reflecting the motion of the object to the locus of the X-ray source 110 while fixing the position of the object. That is, the virtual trajectory of the x-ray source 110 means a virtual trajectory generated by reflecting a change in the position of the object in the trajectory of the x-ray source 110, rather than a trajectory actually moved for scanning by the x-ray source 110 .

Accordingly, the virtual trajectory of the X-ray source 110 is a trajectory of the X-ray source 110 that compensates for the movement of the object. If the object moves during the scan time, the actual X-ray source 110 rotates It is different from the trajectory. The virtual trajectory of the x-ray source 110 is not rotated according to the virtual trajectory but the x-ray source 120 is also rotated to face the rotating x-ray source 110 along the virtual trajectory I suppose.

The image processing unit 140 may generate a virtual trajectory L2 of the x-ray source 110 in the virtual space by reflecting the movement of the head c of the object, as shown in Fig. 9A. Accordingly, the image processing unit 140 calculates the distance between the x-ray source 110 and the head c, the distance between the x-ray source 110 and the x-ray detector 120 based on the virtual locus L2 of the x- The second medical image compensated for the motion can be generated.

9B, the image processing unit 140 generates a virtual trajectory L4 of the x-ray source 110 in the virtual space by reflecting the motion of the object, as shown in Fig. 9B . At this time, not only the movement of the head part c of the object itself but also the movement of the components of the medical imaging device 100 such as the X-ray source 110 and the X-ray detector 120 are reflected in the virtual locus L4 in the virtual space . That is, the virtual trajectory L4 may be a trajectory generated by compensating the motion of the object head c itself, a trajectory generated by compensating the motion of the components of the medical imaging apparatus 100, It may be a trajectory generated by compensating all movements of branches.

10 is a diagram showing a virtual trajectory of an x-ray source 110 through an orthogonal coordinate system according to an embodiment. 5A, the virtual trajectory reflecting the motion of the object can be changed to the virtual trajectory L2 shown in FIG. 9 (see FIG. 5A), as described above, even if the actual trajectory of the x- . The image processing unit 140 may represent a virtual locus L2 of the x-ray source 110 on an orthogonal coordinate system, as shown in Fig. Meanwhile, it is assumed that the X-ray detector 120 is provided at a position facing the X-ray source 110 and rotates according to the virtual trajectory.

In addition, prior to performing the back projection process, the image processing unit 140 may perform a weighting process and a filtering process based on the FDK algorithm, reflecting the virtual trajectory of the X-ray source 110.

Here, the weighting process refers to a process for restoring an intensity value for each projection data. The degree of restoration of the brightness value varies depending on the distance between the X-ray source 110 and the X-ray detector 120.

The distance between the x-ray source 110 and the x-ray detector 120 on the virtual trajectory may be different from the distance between the x-ray source 110 and the x-ray detector 120 on the actual locus. The distance between the x-ray source 110 and the x-ray detector 120 on the virtual trajectory and the distance between the x-ray source 110 and the x-ray detector 120 on the actual locus are determined by the scan time, It can vary greatly.

The image processing unit 140 according to the embodiment calculates the distance between the x-ray source 110 and the x-ray detector 120 based on the virtual trajectory of the x-ray source 110 and performs a weighting process based on the distance, The second medical image in which the brightness value of the second medical image is restored more accurately can be generated. In this case, the image processing unit 140 calculates the distance between the x-ray source 110 and the x-ray detector 120 on the virtual trajectory of the x-ray source 110 according to the scan time or the scan time, By performing the weighting process, the brightness value of the object in the second medical image can be restored more accurately.

Alternatively, the image processing unit 140 according to the embodiment may perform the weighting process using T _SD which is one of the motion parameters. That is, without calculating the distance between the x-ray source 110 and the x-ray detector 120 from the virtual trajectory. The image processing unit 140 may apply an image quality metric process to determine seven motion parameters including T _SD .

In addition, the image processing unit 140 may perform a filtering process based on the FDK algorithm before performing the back projection process. In general, the filtering process is performed based on the row direction of the X-ray detector 120. However, if filtering is performed on the basis of the column direction of the X-ray detector 120 even if the motion of the object occurs, sharp medical images such as shading may occur on the medical image. Accordingly, the image processing unit 140 can perform the filtering process by setting the moving direction of the X-ray source, that is, the tangential direction, as the filtering direction based on the virtual trajectory.

FIGS. 11A, 11B, and 11C are diagrams for explaining a case where a filtering direction is set in a tangential direction of an X-ray source according to another embodiment.

11A is a diagram showing an X-ray source 110 in which motion is not reflected and a region of interest R of an object on an actual trajectory. Referring to FIG. 11A, as described above, the X-ray source 110 rotates 360 degrees according to the rotation locus to irradiate X-rays to the object.

The X-ray detector 120 is provided at a position facing the X-ray source 110, and detects X-rays irradiated from the X-ray source 110. At this time, if the object does not move during the scan time, the image processing unit 140 sets the row direction of the X-ray detector 120 shown in FIG. 11A to the filtering direction, and performs the filtering process.

However, the object may be moved during the scan time, and the region of interest R 'of the object at a specific scan time may be located as shown in FIG. 11B. In this way, the image processing unit 140 can generate a virtual trajectory of the x-ray source 110 as described above. The image processing unit 140 may determine that the x-ray source 110 and the x-ray detector 120 on the virtual trajectory exist in the directions and positions as shown in Fig. 11B at a specific scan time.

In this case, when the image processing unit 140 sets the filtering direction in the first filtering direction shown in FIG. 11B, that is, the column direction of the X-ray detector 120 and then performs the filtering process, shading ) May be generated. In addition, the brightness value for the same area in the medical image is not constant, so it may be difficult to accurately diagnose the area of interest of the object.

11C, the image processing unit 140 according to the embodiment sets the tangential direction of the x-ray source 110, that is, the second filtering direction as the filtering direction, thereby performing the filtering process based on the tangential direction . Accordingly, the image processing unit 140 according to the embodiment can generate a three-dimensional medical image in which the brightness value is restored more accurately.

On the other hand, the curvature of the coordinate in the domain in which the back projection is performed should be considered. For example, if a curved X-ray detector is used, it should reflect the curvature of the detector. Particularly, when the tangential direction of the x-ray source 110 on the virtual locus is set to the filtering direction, the curvature can be continuously changed. Therefore, if the curvature of the center is continuously changed according to the virtual trajectory, the calculation becomes complicated because the curvature at the center must be considered.

At this time, the back projection process based on the FDK algorithm has a predetermined calculation method for each flat type or curved type. Accordingly, even if the curvature of the center of the domain in which the back projection is performed is changed as the filtering direction is changed, the image processing unit 140 according to the embodiment performs the back projection process based on the FDK algorithm, The image can be restored.

On the other hand, when the difference between the predetermined initial motion parameter value and the motion of the object is large, there is a disadvantage that the amount of operation and time required to replace or update the motion parameter value increases. For example, if the initial motion parameter value is set to 0 in the case where there is a lot of motion of the object during scanning, the initial motion parameter value is replaced with an accurate motion parameter value by performing the process described above for the first medical image Or updating the data is required not only a large amount of computation but also a time-consuming disadvantage.

In order to overcome the disadvantages described above, the image processing unit 140 according to the embodiment determines an initial motion parameter value to which a motion of the object is reflected to some extent using a marker, and then performs the above-described process based on the determined initial motion parameter value, The amount of calculation and time required can be reduced. Hereinafter, a method for determining the initial motion parameter value will be described. However, the above-described embodiments and embodiments to be described later are applicable, except for the method of determining the initial motion parameter value, which will be described below. 13A is a view schematically showing a partial medical image including a target object and a marker according to an embodiment, and FIG. 13B is a view for explaining an example of determining an initial motion parameter value at a reference point, FIG. 5 is a view schematically showing a partial medical image subjected to masking according to FIG. FIG. 14 is a graph illustrating an initial motion parameter value generated using an initial motion parameter value at a reference point according to an exemplary embodiment. Hereinafter, the description will be described together to prevent duplication of description.

For example, during scanning, a marker may be attached to the object, and the restored medical image may include a marker as well as a scan region of the object. The marker may be implemented as a substance that does not affect the detection of the scan site of the object, or a substance that affects less.

For example, the marker may be implemented through water, acrylic, synthetic resin or the like, but is not limited thereto. Further, the marker may further include a sponge or the like surrounding the above-mentioned material. Accordingly, the restored medical image is separated from the marker by a predetermined distance or more between the target and the target, and can be more easily identified.

There is no restriction on the possible form of the marker, and the size that can be implemented is also unlimited. At this time, depending on the characteristics of the scan region of the object, it may be difficult to distinguish between the marker and the scan region of the object. In order to overcome this problem, the markers are implemented in various sizes, and the user can select a marker suitable for the scan area of the object and attach the marker to the object. Alternatively, the image processing unit 140 may identify a marker included in the partial medical image through a masking process. A detailed description thereof will be given later.

The marker can be attached to any part of the object and is not limited. For example, in the case where the scan region of the object is the head, there is no limitation such that the marker can be attached to the nose, ear, or the like of the object.

The image processing unit 140 compares the template medical image acquired from the previously stored sinogram with the medical image restored by scanning the object with the marker to identify the marker included in the restored medical image, The initial motion parameter value reflecting the motion of the object can be determined by determining the initial motion parameter value based on the change.

The template medical image reconstructed from the raw data acquired by scanning the marker may be stored in the storage unit 160. At this time, the template medical image may include a plurality of template medical images divided according to the scan time, the scan time, or the scan angle. The template medical image may be generated by the medical imaging apparatus 100 and stored in the storage unit 160 or may be generated from an external device and stored in the storage unit 160 in advance. Alternatively, the template medical image may be stored in an external device, and the control unit 150 may control the communication unit 170 to receive the template medical image from the external device. Hereinafter, a description will be given on the assumption that the image processing unit 140 generates images for convenience of explanation.

For example, the image processor 140 may generate a tomogram between template portions by dividing row data acquired at all scan angles or scan points on the basis of a specific scan time point range or a specific scan angle range. That is, the image processing unit 140 divides the entire scan time point or the entire scan angle into C (C? 2) specific scan time ranges or specific scan angle ranges, and then, based on the row data within each range, A sinogram can be generated.

In one embodiment, when the position at which the scan of the x-ray source 110 is started is 0, the image processing unit 140 sets the raw data acquired from the angle of 0 to 90 degrees in the counterclockwise or clockwise direction To generate a first template portion inter-nogram, and to generate a second template portion inter-nogram based on raw data acquired at an angle of less than 90 ㅀ and less than 180.. In addition, the image processing unit 140 generates a third template part-nodogram based on raw data acquired at angles of 180 to 270 를 based on raw data acquired at angles of 270 to 360 제 4 You can create a template-side intersogram.

Then, the image processing unit 140 may restore the template portion medical image from each template portion between the nograms, and the shapes of the markers displayed on the template portion medical image may be different from each other.

For example, as shown in FIG. 12, the shapes of the markers in the first to fourth template portion medical images M1, M2, M3, and M4 may be different. Here, the first through fourth template medical images M1, M2, M3, and M4 include spherical markers, but there is no limitation on the form in which the markers can be implemented as described above.

On the other hand, the image processing unit 140 may scan a target object with a marker, and may restore a plurality of partial medical images divided according to a specific scan time range or a specific scan angle range as described above. Accordingly, the image processing unit 140 can identify the marker by comparing shapes of the markers displayed on the partial medical image with the template medical image. That is, the image processing unit 140 can distinguish a target object included in the partial medical image from a marker using the pre-stored template partial medical image.

Meanwhile, in order to more accurately identify the marker, the image processing unit 140 may perform a masking process on the partial medical image. For example, FIG. 13A is a view schematically showing a partial medical image including a target object and a marker according to an embodiment, and FIG. 13B is a view schematically showing a partial medical image having a masking process performed on the target object .

The partial medical image shown in FIG. 13A may include the scan area D and the marker M5 of the target object. At this time, the image processing unit 140 may mask the scan region D of the target object to generate a partial medical image including only the marker M5 as shown in FIG. 13B. The image processing unit 140 can more easily identify the marker by comparing the masked partial medical image shown in FIG. 13B with the template partial medical image. In addition, when it is determined that it is difficult to identify the marker according to the scan region of the target object, the user may attach a marker suitable for the scan region of the target object to the target object as described above.

The image processing unit 140 may determine an initial motion parameter value based on a change in the position of the marker on the partial medical image. When the object moves, the marker attached to the object also moves. Accordingly, the image processing unit 140 can track the position of the marker and determine the initial motion parameter value reflecting the motion of the object.

For example, the position of the marker on the first partial medical image may be different from the position of the marker on the second to fourth partial medical images. The image processing unit 140 may determine an initial motion parameter value based on a change in the relative position of the marker on the partial medical image.

On the other hand, since the motion of the object is continuous, it may be different at every scan time or scan time. At this time, an operation overload may occur to determine the motion parameter value at every scan time or scan time.

Accordingly, the image processing unit 140 may determine the initial motion parameter value at every scan time or every scan angle, but may set the reference point for each partial medical image, and then determine only the initial motion parameter value at the set reference point , The amount of computation can be efficiently controlled.

For example, if the first through fourth medical images are obtained by dividing the scan angle 360 by four, the image processing unit 140 divides the first reference point R1 in the first partial medical image by 45 The second reference point R2 in the second partial medical image is set to 135 占, the third reference point R3 in the third partial medical image is set to 225 占 and the fourth reference medical image is set to the fourth The reference point R4 can be set to 315..

In one embodiment, the image processing unit 140 may track the change in position of the marker between the first partial medical image and the second partial medical image to determine an initial motion parameter value at the first reference point R1, The initial motion parameter value at the second reference point R2 can be determined by tracking the change in the position of the marker between the partial medical image and the third partial medical image. The image processing unit 140 may respectively determine initial motion parameter values at the third to fourth reference points R3 and R4 in the above-described manner.

The image processing unit 140 may compare the positional change of the marker at the reference point to determine the initial motion parameter value and then follow it to the line to generate a graph of the initial motion parameter value.

For example, referring to FIG. 14, the image processing unit 140 determines Tx indicating a distance at which the object moves along the x axis at the reference points R1, R2, R3, R4, Can be generated. The image processing unit 140 may also determine other initial motion parameter values in this manner.

Then, the image processing unit 140 may use a graph relating to the initial motion parameter value to determine an accurate motion parameter value. For example, the image processing unit 140 may determine a motion parameter value from the first medical image based on a graph relating to an initial motion parameter value.

The image processing unit 140 may replace or update the motion parameter values with correct values by using all of the motion parameter values at the control point and the initial motion parameter values described above. Alternatively, if it is determined that the motion of the target object is small, the image processing unit 140 sets the initial motion parameter value to 0, and then uses only the graph relating to the motion parameter value at the control point, There is no restriction such that it can be replaced or updated.

On the other hand, the medical imaging apparatus 1 may be provided with a control unit 150. The controller 150 may be implemented through a processor such as a processor.

The control unit 150 may control the overall operation of the medical imaging apparatus 100. [ For example, the control unit 150 may generate a control signal for controlling the components of the medical imaging apparatus 100 to control the operation of each component of the medical imaging apparatus 100.

In one embodiment, the controller 150 controls the operation of the X-ray source 110 and the X-ray detector 120 based on control commands input from the user interface 130 to acquire row data at various angles There is no restriction, such as can be.

In another example, the control unit 150 may control the data acquisition circuit 116 via the control signal so that the row data acquired by the X-ray detector 120 is transmitted to the image processing unit 140. In addition, the controller 150 controls the operation of the table 190 through the control signal, so that the object can enter the inside of the bore. In addition, the control unit 150 can provide the acquired medical image to the user through the user interface unit 130, and there is no limitation.

Meanwhile, the medical imaging apparatus 100 may be provided with a storage unit 160.

The storage unit 160 may be a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (for example, SD or XD memory) A random access memory (SRAM), a read only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM) A magnetic disk, or an optical disk. However, the present invention is not limited thereto and may be implemented in any other form known in the art.

For example, the storage unit 160 may store various data related to the control method of the operation of the medical imaging apparatus 100. Accordingly, the control unit 150 can control the operation of the medical imaging apparatus 100 using the data stored in the storage unit 160. As another example, there is no limitation on the type of data that can be stored, such as the medical image restored through the image processing unit 140 can be stored in the storage unit 160.

The control unit 150 and the storage unit 160 may be implemented as separate chips, but the controller 150 and the storage unit 160 may be integrated into a single chip.

Meanwhile, the medical imaging apparatus 100 may be provided with a communication unit 170.

The communication unit 170 may include at least one of a wired communication module and a wireless communication module. Accordingly, the communication unit 180 can exchange data with an external device or the like through at least one of a wired communication network and a wireless communication network. The wired communication module and the wireless communication module may be implemented as separate chips or integrated into a single chip.

In one embodiment, the communication unit 170 can exchange data with other medical devices in a hospital server or a hospital connected through a PACS (Picture Archiving and Communication System) through a wired / wireless communication network. Data can be exchanged in accordance with the Digital Imaging and Communications in Medicine (DICOM) standard. In another embodiment, the communication unit 170 supports the sharing of the data related to the diagnosis of the object and the medical image generated by the other medical imaging apparatus 100 through the wire / wireless communication method, Thereby enabling diagnosis.

In another embodiment, the communication unit 170 may receive a diagnosis history or a treatment schedule of a patient from a server and utilize the diagnosis history to diagnose a subject. The communication unit 170 may perform data communication with a doctor or a customer's electronic apparatus as well as a server or a medical apparatus in a hospital. In another embodiment, the communication unit 170 may transmit the wired / wireless communication network to the user and receive feedback from the user about the abnormality of the medical device or the quality information about the medical image.

At least one of the components of the medical imaging apparatus 100 may be included in the workstation 200. For example, referring to FIG. 7B, the user interface unit 130, the image processing unit 140, the control unit 150, the storage unit 160, and the communication unit 170 may be included in the workstation 200. Data or the like between the components of the medical imaging apparatus 100 that are not included in the work station 200 such as the work station 200 and the x-ray source 110 and the x-ray detector 120, Can be exchanged.

Referring to FIG. 1B, the workstation 200 may be provided with a user interface unit 130 for user operation. The user interface unit 130 may receive an instruction or command for controlling the operation of the medical imaging apparatus 100 from a user and may provide various screens related to the operation of the medical imaging apparatus 100.

In one embodiment, the user interface unit 130 may be implemented through a display 131 that visually provides various information to a user, a keyboard 132 that receives various control commands from a user, and a mouse 133. The user interface unit 130 may be implemented through a trackball, a foot switch, a foot pedal, or the like, and may be implemented through various devices capable of interacting with a user, none. 1B, the user interface unit 130 may be provided on the upper portion of the main body 200. However, if the footswitch and the foot pedal are implemented as described above, the user interface unit 130 may be provided below the main body 200 .

The user interface unit 130 displays a graphical user interface (GUI) on the display 131 so that various information and commands exchange between the user and the medical imaging apparatus 100 can be performed more conveniently. So that the interaction between the user and the medical imaging apparatus 100 is enabled. In this case, the user interface unit 130 may be implemented by only the display 131. [

The user interface unit 130 includes a user interface unit 130, such as a command relating to the movement of the table 190 in which the object is located from the user, a command relating to selection of the X-ray imaging mode, a command relating to the X-ray imaging conditions, And a control command related to the operation of the medical imaging apparatus 100 may be input. In addition, the user can input an X-ray photographing start command, select a type of photographing, set a region of interest, etc. through the user interface unit 130, and there is no limitation.

Meanwhile, the workstation 200 and the housing 101 including the components for performing scanning of the object may be provided together in the photographing room. Alternatively, the photographing room where the object is scanned and the control room for controlling the photographing and image processing operations of the object can be separated. In this case, a housing 101 including components for performing scanning of a target object may be provided in the photographing room, and a workstation 200 may be provided in the scan room.

However, not only the workstation 200 is provided in the control room, but the process of controlling the scanning of the object is performed in the control room, and the image processing can be performed in a separate room. At this time, the work station 200 provided in the control room corresponds to the first work station, and the work station provided in the separate room corresponds to the second work station. The above-described workstation 200 includes at least one of a first workstation and a second workstation.

Hereinafter, an operation flow of the medical imaging apparatus 100 will be briefly described.

FIG. 15 is a diagram for explaining an operational flow for a medical imaging apparatus that generates a second image based on a motion parameter value according to an embodiment.

Referring to FIG. 15, the medical imaging apparatus can acquire the row data through the X-ray detector and perform the preprocessing process on the row data as described above (step 1000). Projection data refers to data derived by performing a preprocessing process on a specific scan angle, or row data of all channels acquired at a scan time.

The medical imaging device may generate a sinogram by collecting projection data for all scan angles (1010). Here, the sinogram means a set of projection data related to all scan angles.

Accordingly, the medical imaging device can apply a mathematical operation process such as a weighting process and a filtering process to the sinogram, and apply the back projection process to generate the first medical image (1020). Here, the first medical image is an image reconstructed based on a preset initial motion parameter value, and corresponds to an image in which the motion of the object generated during the actual scan is not reflected.

The medical imaging device may determine a motion parameter value in the first medical image. For example, the motion parameter refers to a parameter for expressing the degree of motion of a region of interest of an object. Expressed in the coordinate system of the drawing sheet, the motion parameter is represented by 6 values in the moving direction from the x-axis, the y-axis, and the z-axis, with the position of the region of interest of the object at the start of scanning as the origin . The motion parameter may further include a value indicating a distance between the x-ray source and the x-ray detector.

During the scan, the distance between the x-ray source, the x-ray, the detector, and the object may be changed by the movement of the object itself, but may also be changed by the movement of the components of the medical imaging apparatus 100. For example, as described above, the scan is performed while moving the X-ray source and the X-ray detector in the direction of the axis of FIG. 5, such as the mobile computer single layer apparatus, or the scan is performed while the table moves in the direction of the axis D1 in FIG. The probability of changing the distance between the X-ray source and the X-ray detector and the object may be high. Accordingly, the medical imaging apparatus according to the embodiment can determine not only the motion of the object itself, but also the motion parameter values including the relative motion of the object reflecting the motion of the components of the medical imaging apparatus.

For example, the medical imaging device may calculate the motion parameter value for each specific point through the image quality process as an image quality evaluation technique, and update the motion parameter value based on the calculation result (1030). In this case, the medical imaging device sets a variable as a motion parameter value, and calculates an entropy value and a sharpness value about an edge area in a region in which the object is displayed in the first medical image, ) ≪ / RTI > value to the resulting value, so that an image quality process can be applied. Here, the result value may be referred to as an image quality metric value.

In one embodiment, when the image quality metric value is one of a sharpness value and a gradient value, the medical image device sets a motion parameter value at which the image quality metric value becomes maximum to a motion parameter at the scan time or scan time Value. In another embodiment, the medical imaging apparatus may update the motion parameter value when the image quality metric value becomes the minimum, with the motion parameter value at the corresponding scan time or scan time, when the image quality metric value is the entropy value.

On the other hand, since the motion of the object is continuous, it may be different at every scan time or scan time. At this time, an operation overload occurs to obtain motion parameter values at every scan time or scan time. Accordingly, the medical imaging device can perform the motion parameter value determination operation repeatedly at a plurality of specific points to update the motion parameter value, and calculate the motion parameter value at the entire point based on the motion parameter value. At this time, the point can be set based on the scan point, i.e., the view or the scan time.

For example, the medical imaging apparatus sets a plurality of control points according to a scan time or a scan time, determines motion parameter values at a plurality of set control points, and then determines movement parameters related to the entire scan time or scan time You can create a graph that approximates a value.

The medical imaging apparatus can generate a graph of motion parameters for the entire scan time or the entire scan time based on motion parameter values at a plurality of control points and update the motion parameter values at the entire scan time or scan time.

In addition, the medical imaging device may generate a second medical image based on the updated motion parameter value (1040). Here, the second medical image is a medical image reconstructed by compensating for the motion of the object, and refers to a reconstructed medical image based on the updated motion parameter values through the above-described process.

For example, a medical imaging device can generate a virtual trajectory of an x-ray source using a graph of motion parameters. Here, the virtual trajectory of the x-ray source means a trajectory generated by compensating the movement of the object with respect to the actual trajectory moved when the x-ray source irradiates the x-ray source. That is, the medical imaging apparatus can generate a virtual trajectory by compensating that the x-ray source is shifted by a specific distance in the opposite direction of the specific direction, if the object has been moved by a specific direction and a certain distance with respect to the origin at a specific point in time have.

For example, if an x-ray source moves a certain distance in a specific direction at a particular point in time, the motion parameter may be represented as the object is moved a certain distance in the opposite direction of the specific direction. Then, the medical imaging device compensates for the motion of the object, and generates a virtual trajectory that is reflected to the movement of the x-ray source by generating a virtual trajectory in which the x-ray source is moved by a specific distance in a specific direction at a specific time.

Accordingly, in applying the weighting process, the filtering process, and the back projection process to the projection data, the medical imaging device can reflect the distance between the X-ray source, the object, and the X-ray detector based on the virtual trajectory. In addition, in applying the filtering process to the medical imaging apparatus, the tangential direction of the virtual trajectory is set to the filtering direction, thereby providing the second medical image in which the brightness value of the target object is restored more accurately.

16 is a view for explaining an operation flow of a medical imaging apparatus for generating a second medical image based on an initial motion parameter value determined using a partial medical image according to an embodiment.

Referring to FIG. 16, the medical imaging device may acquire project line data (1100). The method of acquiring projection data is the same as that of step 1000 described above, so a detailed description thereof will be omitted. The medical imaging apparatus performs projection data on all scan angles or all scan points in accordance with a preset scan angle range or a preset scan point range And a plurality of partial intersymograms can be generated by dividing. Here, the partial sinogram means a set of projection data in a predetermined scan angle range or a predetermined scan time range.

The medical imaging device may apply a mathematical computation process such as a weighting process, a filtering process, and a back projection process to each of the plurality of partial inter-nograms to generate a plurality of partial medical images (1110).

The medical imaging device can compare the previously stored partial medical image with the generated partial medical image to identify the marker included in the generated partial medical image. Since the pre-stored template partial medical image includes the shape of the marker at a specific scan time point range or a specific scan angle range, the medical image device uses the shape of the marker included in the pre-stored template partial medical image, A marker may be identified in the image (1120).

The medical imaging device may determine an initial motion parameter value based on a change in the position of the marker on the plurality of partial medical images (1130). If the initial motion parameter value does not reflect the motion of the object, it takes a lot of computation and time to determine the correct motion parameter value. Therefore, the medical imaging apparatus according to the embodiment can roughly determine the initial motion parameter value reflecting the movement of the target object by tracking the position of the marker, and then calculate or replace or update the accurate motion parameter value based on the initial motion parameter value.

For example, the medical imaging device according to the embodiment may set at least one reference point and determine an initial motion parameter value at the set at least one reference point.

The reference point can be set according to various methods. For example, if four partial medical images are generated by dividing the scan angle of 360 전체 into four, each partial medical image can be reconstructed based on raw data acquired according to a scan angle range of 90.. In one embodiment, as described above, the first partial medical image may be reconstructed based on the raw data obtained in a range of scan angles of 0 to 90 ㅀ, and the second partial medical image may be reconstructed from 90 ㅀ to 180 ㅀ , The third partial medical image can be reconstructed based on the raw data acquired in the range of the scan angles of 180 ㅀ to 270 ㅀ and the fourth partial medical image of 270 ㅀ to less than 360..

At this time, the reference point can be set based on 45 해당 which corresponds to the average of the scan angle range 90.. For example, the reference point in the first partial medical image is 45 ㅀ, the reference point in the second partial medical image is 135,, the reference point in the third partial medical image is 135,, The reference point in the image can be set to 225,, and the reference point in the fourth partial medical image can be set to 315..

In addition, the medical imaging device can set a plurality of reference points in various ways. At this time, as the reference point is increased, a higher calculation amount is required. The medical imaging apparatus can set a reference point according to a predetermined number or determine a calculation amount that can be processed, and can automatically set a reference point according to a determination result There is no.

The medical imaging device may track the position of the changed marker on the partial medical image to determine the initial motion parameter value at the reference point 1130 and then determine the graph of the initial motion parameter value through approximation.

The medical imaging device may apply a mathematical computation process such as a weighting process, a filtering process to the entire sinogram, and apply a back projection process to generate a first medical image (1140). Here, the first medical image may be a reconstructed image based on the initial motion parameter value reflecting the motion of the object through the marker.

The medical imaging device may calculate motion parameter values in the first medical image. At this time, since the motion of the object is reflected on the first medical image through the marker, the medical imaging device can calculate the accurate motion parameter value more quickly and then update the motion parameter value with the calculated value (1150).

The medical imaging device may generate a second medical image based on the updated motion parameter values (1160). Since the operation is the same as that in step 1040, a detailed description will be omitted.

When the motion of the object is large, the amount of computation and time required to generate the second medical image may vary depending on how the initial motion parameter value is set. Accordingly, the medical imaging apparatus generates a plurality of partial medical images, and then generates a first medical image reflecting the movement of the target by tracking the positions of the markers in the plurality of partial medical images, The value can be calculated more quickly. Accordingly, the medical imaging apparatus according to the embodiment can generate the second medical image more quickly.

FIG. 17 is a diagram for explaining an operation flow of a medical imaging apparatus for generating a medical image in which motion of an object is compensated by irradiating an X-ray according to an embodiment.

Referring to FIG. 17, a medical imaging device may irradiate an object with an X-ray through an X-ray source (1200). At this time, the medical imaging apparatus can scan the region of interest of the object by irradiating the x-ray source while rotating 360 degrees around the region of interest of the object to be diagnosed, through the medical image, with respect to the object.

At this time, an X-ray detector is provided at a position facing the X-ray source, and the medical imaging apparatus can detect the X-ray passing through the inside or the outside of the object by being irradiated from the X-ray source through the X-ray detector, The row data may be obtained 1210.

At this time, the medical imaging apparatus can determine the motion parameters from the medical image restored based on the row data (1120). The medical imaging apparatus determines movement parameters from the medical image without attaching an external device or camera for identifying the movement of the object by attaching a marker or the like to a region of interest of the object and tracking the movement marker, A medical image compensated for motion can be generated and provided. Therefore, the medical imaging apparatus according to the embodiment not only reduces the cost, but also enhances the image quality of the medical image. At this time, a detailed description of the method for determining the motion parameters from the medical image has been described above, so it will be omitted.

The medical imaging device may generate a virtual trajectory of the x-ray source based on the determined motion parameters (1130). Based on the initial position of the object, the position of the object by the scan time continuously changes due to the movement of the object. Also, the actual movement trajectory of the x-ray source is fixed. Therefore, the medical imaging apparatus can generate a virtual trajectory of the x-ray source in the virtual space reflecting the motion of the object. In restoring the three-dimensional medical image, the medical imaging apparatus can reflect the distance between the x-ray source, the object, and the detector according to the virtual trajectory in various arithmetic processes required. The tangential direction in the virtual trajectory is filtered Direction. Accordingly, the medical imaging device generates the medical image compensated for the movement of the object (1140), and visually provides the generated medical image to the user through the display or the like.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory only and are not restrictive of the invention, as claimed, and it is to be understood that the invention is not limited to the disclosed embodiments.

Also, the terms used herein are used to illustrate the embodiments and are not intended to limit and / or limit the disclosed invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more features, integers, steps, operations, elements, components, or combinations thereof.

It is also to be understood that terms including ordinals such as " first ", "second ", and the like used herein may be used to describe various elements, but the elements are not limited by the terms, It is used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The term "and / or" includes any combination of a plurality of related listed items or any of a plurality of related listed items.

The terms "unit," "block," "member," "module," and the like used in the entire specification are intended to include at least one Or a unit for processing a function or an operation of the apparatus. For example, hardware such as software, FPGA, or ASIC. However, the meaning of "~", "~", "~ block", "absence", "~ module" is not limited to software or hardware, Quot ;, " block ", "absent "," module ", and the like may be constructions stored in accessible storage medium and performed by one or more processors.

1: medical imaging device

Claims (19)

An X-ray source for irradiating X-rays;
An X-ray detector for detecting X-rays irradiated from the X-ray source and acquiring raw data; And
Determining a motion parameter indicating motion of at least one of the object, the x-ray source, and the x-ray detector from the medical image reconstructed based on the obtained raw data, and calculating a motion parameter of the x-ray source based on the determined motion parameter An image processing unit for restoring a medical image obtained by compensating a motion of a target object based on a locus;
And a medical imaging device. The method according to claim 1,
Wherein the image processing unit comprises:
And applies the image quality metric process to the medical image restored based on the acquired raw data to determine a motion parameter value at at least one scan time or scan time. 3. The method of claim 2,
Wherein the image processing unit comprises:
Wherein at least one control point is set, a motion parameter value at the set at least one control point is determined, and the motion parameter value is approximated from the determined motion parameter value to generate a graph for each motion parameter. 3. The method of claim 2,
Wherein the image processing unit comprises:
The motion parameter is set as a variable, and the image quality metric process in which at least one of an entropy value, a sharpness value, and a gradient value is set as a result value is applied so that at least one scan time or a scan time Wherein the motion parameter value of the medical imaging device is determined. The method of claim 3,
Wherein the image processing unit comprises:
Calculates a motion parameter value at each scan time or scan time using the generated graph, and generates a virtual trajectory of the X-ray reflecting movement of the object based on the calculated motion parameter value. In the first aspect,
Wherein the image processing unit comprises:
And performs a weighting process on the projection data derived from the row data based on a distance between the X-ray source and the X-ray detector on a virtual trajectory of the generated X-ray source. The method according to claim 1,
Wherein the image processing unit comprises:
And performs a filtering process on the projection data derived from the row data based on the tangential direction of the virtual trajectory of the generated X-ray source. The method according to claim 1,
Wherein the motion parameter comprises:
A relative movement of the object reflecting movement of the object itself and movement of at least one of the X-ray source and the X-ray detector; The method according to claim 1,
Wherein the motion parameter comprises:
And a parameter indicative of a distance between the x-ray source and the x-ray detector. The method according to claim 1,
Wherein the image processing unit comprises:
A medical imaging apparatus for identifying a marker on the partial medical image by comparing a pre-stored template partial medical image and a partial medical image obtained by irradiating an X-ray to a target object having a marker attached thereto. The method according to claim 1,
Wherein the image processing unit comprises:
A first motion parameter value tracking unit for tracking a position of a marker identified on the partial medical image and restoring a medical image compensated for motion of the object based on the determined initial motion parameter value. An interface unit for receiving a scan command regarding a target object from a user;
A controller for controlling the operation of the X-ray source and the X-ray detector so as to acquire raw data according to the received scan command; And
Generating a first medical image from the acquired raw data, generating a virtual trajectory of the X-ray source based on the motion parameter determined from the first medical image, and compensating for motion of the object based on the virtual trajectory of the X- An image processor for restoring a second medical image;
≪ / RTI > 13. The method of claim 12,
Wherein the image processing unit comprises:
And applying an image quality metric process to the first medical image reconstructed based on the acquired raw data to determine a motion parameter value at at least one scan time or scan time. In Item 12,
Wherein the image processing unit comprises:
And performs a weighting process on the projection data derived from the row data based on a distance between the X-ray source and the X-ray detector on a virtual trajectory of the generated X-ray source. In Item 12,
Wherein the image processing unit comprises:
And performs a weighting process on the projection data derived from the row data by using a parameter indicating a distance between the X-ray source and the X-ray detector among the determined motion parameters. Receiving a scan command for a target object from a user;
Controlling an operation of an X-ray source and an X-ray detector so as to obtain raw data according to the input scan command; And
Generating a first medical image from the acquired raw data, generating a virtual trajectory of the x-ray source based on the motion parameter determined from the first medical image, and compensating the motion of the object based on the virtual trajectory of the x- Restoring the second medical image;
The control method comprising the steps of: 17. The method of claim 16,
Wherein,
Applying an image quality metric process to the first medical image restored based on the acquired raw data to determine a motion parameter value at at least one scan time or scan time;
The control method comprising the steps of: 18. The method of claim 17,
Wherein,
Setting at least one control point, determining a motion parameter value at the set at least one control point, and approximating the determined motion parameter value to generate a graph for each motion parameter;
The control method comprising the steps of: 19. The method of claim 18,
Wherein,
Calculating a motion parameter value at each scan time or scan time using the generated graph and generating a virtual trajectory of the X-ray reflecting movement of the object based on the calculated motion parameter value;
The control method comprising the steps of:

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