JP2009240571A - Image transmitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten the waiting time before work start in the case of performing observation/analysis processing or the like of moving images relating to an object in an external device. <P>SOLUTION: An image data storage part 10 stores the data of a plurality of projection images relating to the object, which are collected in an order. A transmission order determination part 11 determines the transmission order of the plurality of projection images differently from the order of gathering them. An image transmission part 12 transmits the plurality of projection images to the external device 20 in the transmission order determined in the transmission order determination part 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image transmission apparatus that transmits data of a plurality of projection images related to a subject collected in order by an X-ray diagnostic apparatus or the like to an external apparatus.

  In recent years, not only an X-ray computed tomography apparatus but also a C-arm system, a technique for reconstructing a three-dimensional image from a plurality of projection images photographed from multiple directions is being put into practical use. In the C-arm system, the X-ray tube is rotated about 180 ° together with the X-ray detector, and imaging is repeated at about 20 frames / second during that time. For example, if the examination target is the heart, two-frame images are selected from two moving images obtained by angiographic examination from two directions, and a blood vessel stereoscopic image is constructed.

  The obtained moving image may be observed on the collection device, but is often transferred to an external device such as another personal computer or a workstation for observation and analysis. When working with an external device different from the collection device, it is necessary to transfer moving image data to the external device. Since there are generally about 200 frames of moving images, it takes a considerable amount of time to transfer the images, and the user must wait until all the frames have been transferred. In particular, since the cardiovascular three-dimensional construction is assumed to be used during surgery, the waiting time is wasted, and as a result, the entire operation time is extended, which is a problem.

In addition, as a well-known document relevant to this application, there exist the following, for example.
US Patent Publication No. 6047080

  As described above, in order to observe and analyze the collected moving image with the external device, it is necessary to transfer the data of the moving image to the external device. Since a moving image has a large amount of data, this transfer requires an enormous amount of time, and there is a problem that the user cannot start work until transfer of all data is completed.

  The present invention has been made in view of the above circumstances, and provides an image transmission device capable of reducing the waiting time until the start of work when a moving image related to a subject is observed / analyzed by an external device. The purpose is that.

  In order to achieve the above object, the present invention takes the following measures.

  The present invention includes a storage unit that stores data of a plurality of projection images related to a subject collected in order, and a transmission unit that transmits the plurality of projection images to an external device in an order different from the order. An image transmission device is provided.

  As described above, according to the present invention, it is possible to provide an image transmission apparatus capable of reducing the waiting time until the start of work when a moving image related to a subject is observed / analyzed by an external apparatus.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, taking as an example the case where an image transmission apparatus according to the present invention is applied to an X-ray diagnostic apparatus.

  As shown in FIG. 1, the X-ray diagnostic apparatus has a C-arm device 5. The C arm device 5 includes a C arm 16, a floor or ceiling suspension support mechanism that supports the C arm 16 so as to be rotatable about three orthogonal axes, and a rotational drive source. The X-ray tube 1 is attached to one end of the C arm 16. The X-ray control unit 4 applies a tube voltage between the electrodes of the X-ray tube 1 to generate X-rays from the X-ray tube 1 in accordance with the control of the system control unit 9, and the cathode filament of the X-ray tube 1 To supply a heating current. The X-ray detector 2 is attached to the other end of the C arm 16. The X-ray tube 1 and the X-ray detector 2 face each other with the subject P on the top 3 interposed therebetween. The X-ray detector 2 is composed of, for example, a combination of an image intensifier and a TV camera. Alternatively, the X-ray detector 2 includes a flat panel detector (FPD: planar X-ray detector) having semiconductor detection elements arranged in a matrix. The C arm / top movement control unit 6 supplies electric power to the drive source for rotating the C arm 16 according to the control of the system control unit 9. The C arm / top plate movement control unit 6 supplies power to the drive source for moving the top plate 3 in accordance with the control of the system control unit 9.

  In the present X-ray diagnostic apparatus, an electrocardiograph 7 is equipped to measure the subject P and generate an electrocardiogram. The image data storage unit 10 stores data regarding a plurality of projection images generated by the X-ray detector 2 in association with cardiac phase data acquired by the system control unit 9 from the electrocardiogram. As shown in FIG. 2, the cardiac phase is defined as a scale for defining each time point in the period from the R wave of the electrocardiogram to the next R wave. The time period until is normalized to 100%, and each time point in the period is expressed in units of percent.

  The plurality of projection images constitute a moving image, and are continuously captured over a plurality of heartbeat cycles, preferably at least three heartbeat cycles, at a speed of shooting 20 frames / second, that is, 20 frames per second. Assume that the number of photographed projection images is N. The electrocardiogram is measured in parallel with the photographing of the plurality of projection images, and the data of the plurality of projection images is stored in the image data storage unit 10 together with the data of the cardiac phase (%) specified by the system control unit 9.

  Further, as shown in FIG. 3, in so-called rotational imaging in which imaging is repeated while rotating the C-arm 16, an imaging angle (a rotation angle of the X-ray tube 1) is associated with each projection image together with a cardiac phase. The operation unit 8 is provided to transmit various commands from the user to the system control unit 9, and includes various input devices such as a keyboard and a mouse.

  By the way, in order to perform operations such as observation and analysis using the projection image of the subject in the external device 20, the moving image data of the projection image stored in the image data storage unit 10 is transmitted via the network NW. There is a need. However, considering cardiovascular stereoscopic display here, the minimum required image for construction is only two frames in the moving image data. Therefore, it is not necessary to transfer all frames of moving image data.

  Therefore, in the present embodiment, a predetermined frame (at least two frames) of the moving image data of the projection image is preferentially transmitted. For this purpose, in this embodiment, a transmission order determination unit 11 and an image transmission unit 12 are provided as image transmission apparatuses. The transmission order determination unit 11 determines the frame transmission order so that a predetermined frame is preferentially transmitted when the image transmission unit 12 transmits the moving image data of the projection image. Details of this processing will be described later. The image transmission unit 12 transmits the moving image data of the projection image to the external device 20 via the network NW according to the frame order determined by the transmission order determination unit 11.

  Hereinafter, specific contents of the frame transmission order determination process in the transmission order determination unit 11 will be described according to each embodiment.

Example 1
In the first embodiment, one image (one frame) is preferentially transmitted for one heartbeat based on an electrocardiogram signal.
FIG. 4 is a diagram illustrating a frame transmission order according to the first embodiment. In FIG. 4, the numbers attached to the images indicate the order of collection. As shown in FIG. 4, the transmission order determining unit 11 preferentially transmits one frame of the same-phase image per heart beat based on the electrocardiogram signal among the collected moving images. It is assumed that the cardiac phase to be transmitted can be set in advance. Here, a frame corresponding to the end diastole (see FIG. 2) with relatively little temporal variation in cardiac motion is preferentially transmitted. In this way, by using an almost stationary image, an accurate cardiovascular three-dimensional image can be constructed. When the necessary frame transfer is completed (Δ in the figure), the external device 20 can browse and work. The remaining images are sequentially transferred as necessary.

  FIG. 5 shows a display example of a projected image displayed on the screen of the external device 20. As shown in FIG. 4, the transmitted frame images are displayed side by side. In addition to this, it is also possible to display in chronological order as in a normal moving image display. In the case of the cardiovascular three-dimensional display, the images are displayed side by side as shown in FIG. 4, and then the operator selects two desired frames, and the cardiovascular three-dimensional model is reconstructed.

  With this configuration, the frame of the end-diastolic heart phase with relatively little movement necessary for blood vessel stereoscopic display is preferentially transmitted to the external device 20, so that the operator transfers all moving image data. There is no need to wait until As a result, it is possible to quickly present a clear and clear stereoscopic image to the external device 20, so that the waiting time until the start of work such as observation / analysis processing can be shortened. Note that a frame at the end systole may be preferentially transmitted instead of the end diastole.

(Example 2)
In the second embodiment, an image having a specific cardiac phase is preferentially transmitted based on an electrocardiogram signal.
FIG. 6 is a diagram illustrating a frame transmission order according to the second embodiment. The transmission order determination unit 11 preferentially transmits an image in a specific period in the cardiac phase based on the electrocardiogram signal among the collected images. For example, in FIG. 6, the post-diastolic stable period (see FIG. 2) with relatively little heart movement is set as the specific period. In addition, it is good also considering the stable period after contraction as a specific period instead of the stable period after expansion.

(Example 3)
In the third embodiment, images are transmitted in the order of the end diastole, the end systole and the intermediate period based on the electrocardiogram signal.
FIG. 7 is a diagram illustrating the frame transmission order according to the third embodiment. The transmission order determining unit 11 first transmits an image group corresponding to the end diastole in the cardiac phase based on the electrocardiogram signal among the collected images, and then transmits an image group at the end systole, and finally The transmission order is determined so as to transmit the intermediate image group. Note that the transmission order is not limited to the above, and priority may be given to the end systole.

  In this way, since the end-diastolic and end-systolic frames with relatively little motion are preferentially sent, the operator can work using clear images.

Example 4
In the fourth embodiment, collected images are thinned out and transmitted.
FIG. 8 is a diagram illustrating a frame transmission order according to the fourth embodiment. The transmission order determination unit 11 determines the transmission order so that the collected images are thinned and transmitted at every predetermined shooting time. In the external device 20, the images transmitted from the image transmission unit 12 are rearranged at any time and displayed at the optimum speed. Thus, the external device 20 is initially displayed as a moving image with a low frame rate (fps: frames per second), but as the time elapses, the frame rate of the moving image displayed gradually increases. When an image is transmitted from the image transmission unit 12 as shown in FIG. 8, it can be initially observed at 7.5 fps, and can be observed at 15 fps and 30 fps at a gradually higher frame rate. The frame thinning method can be arbitrarily set.

  FIG. 9 shows a display example on the external device 20 in the fourth embodiment. For example, when the data is transferred after being thinned, the frame rate is increased and displayed as soon as the thinned frame arrives. At that time, the actual display frame rate is displayed. In addition, a percentage display or a bar graph is displayed so that the ratio of transferred and untransferred can be understood.

(Example 5)
In the fifth embodiment, transmission is performed preferentially from frames that have been observed in detail by a collection device or the like.
FIG. 10 is a diagram illustrating a frame transmission order according to the fifth embodiment. The transmission order determining unit 11 determines the transmission order so as to preferentially transmit frames that have been observed in detail by a transmission source collection device or the like based on operation information for each of the collected images. The operation information includes, for example, reproduction information (rewinding reproduction, pause) when a doctor or operator reconstructs an image based on projection image data with an X-ray diagnostic apparatus and observes it on a monitor (not shown). Etc.). The operation information input from the operation unit 8 is stored in the image data storage unit 10 in association with each projection image.

  For example, the transmission order determination unit 11 preferentially transmits frames that have been paused at the transmission source among the collected images. As a derivation, a frame that has been rewound or slow-played at the transmission source is preferentially transmitted. By doing so, it is possible to observe / analyze an image that is observed in detail by the collection device or the like in the external device 20 without waiting for all frames to be transferred.

(Example 6)
In the sixth embodiment, a frame in which a blood vessel is filled with a contrast medium is preferentially transmitted in the collected image.
FIG. 11 is a diagram illustrating the frame transmission order according to the sixth embodiment. The transmission order determination unit 11 determines a transmission order by giving priority to a frame having a high image density among the collected images. Alternatively, the state of the contrast medium injector signal of the contrast medium injector (not shown) is associated with each projection image, and transmission is performed with priority from the frame during the period when the contrast medium injector signal is in the ON state. To do. For example, as shown in FIG. 11, in the collected image, the external frame is in the order from the middle frame (10th frame in FIG. 11) to the previous and subsequent frames (8th and 11th frames in FIG. 11). Transmit to device 20.

  In this way, it is possible to observe / analyze an image that has been sharpened with a contrast medium by the collection device or the like in the external device 20 without waiting for all the frames to be transferred. Also, since there is a delay of several seconds from when the contrast agent injector signal is turned on until the blood vessel is actually imaged, it is better to send it preferentially from the frame with the delay at the time when the injector signal is on. . Moreover, you may make it send in order of an intermediate | middle flame | frame to the frame before and behind it, among the time when the contrast agent is inject | poured.

(Example 7)
In the seventh embodiment, a frame in which the heart motion is intense is preferentially transmitted.
FIG. 12 is a diagram illustrating the frame transmission order according to the seventh embodiment. The transmission order determination unit 11 determines the transmission order by giving priority to a frame in which the heart motion is intense among the collected images. Generally, a frame in which the heart is moving is difficult to see unless it is sampled finely, but a frame that is almost stopped is relatively clear even if the sampling is rough. Therefore, as shown in FIG. 12, priority is given to a frame in which the heart is intense, such as a period during which the heart is contracting or a period during which the heart is expanding. The determination of the heart motion can be made, for example, based on an electrocardiogram signal or based on the magnitude of the difference from the previous frame. In this way, the operator can perform observation / analysis and the like on the external device using a relatively clear image over the entire time when the image is collected.

(Example 8)
In the eighth embodiment, the bed (top plate) preferentially transmits a frame in a stationary state.
FIG. 13 is a diagram illustrating the transmission order of frames in the embodiment. The transmission order determination unit 11 determines the transmission order by giving priority to a frame when the top 3 is not moving among the collected images. The system control unit 9 acquires the driving state (moving / stopping) of the C-arm / top plate movement control unit 6 and stores it in the image data storage unit 10 in association with each projection image. The transmission order determining unit 11 determines the frame to be transmitted with priority by determining the moving state of the top board 3 based on the driving state. In general, since an image when the bed is moving is not suitable for observation, an image in which the bed is stationary is preferentially transmitted. On the contrary, depending on the clinical situation, it may be easier to see the moving image by sending the frame moving the bed preferentially.

Example 9
In the ninth embodiment, first, two frames having a concentric phase and an imaging angle of about 90 degrees are preferentially transmitted. 14 and 15 are diagrams illustrating the frame transmission order according to the ninth embodiment. Here, a case where volume data is created by performing a three-dimensional image reconstruction process on a cardiovascular projection image in an external device will be described.

  The following method is adopted as the order of data processing in volume data reconstruction. First, the operator designates feature points on the two images. Of the two images, images having the same cardiac phase and a shooting angle of about 90 degrees are selected from the 200 images. For example, the 50th frame and the 150th frame are selected. Next, feature points are specified with about 1 to 8 images. Here, for example, the first, 20, 40, 70, 100, 130, 180, and 200 frames are selected. Next, tracking is performed. Tracking is first performed in sections 1-20, then 20-40, and finally 180-200.

  Therefore, in such a case, as shown in FIG. 14, the transmission order determination unit 11 first transmits two frames having the same cardiac phase and a shooting angle of about 90 degrees apart, and then, the first, 20th of the concentric phase. , 40, 70, 100, 130, 180, 200 frames, 2nd to 19th frames, then 21st to 39th frames, and finally 181st to 199th frames Determine the transmission order.

  Based on the electrocardiogram signal and the imaging angle (rotation angle of the X-ray tube 1) associated with each frame in the collected images, the transmission order determination unit 11 separates the imaging angle by about 90 degrees in a concentric phase. The transmission order is determined so that two frames are transmitted first. For example, two substantially orthogonal images that are suitable for the three-dimensional coordinate calculation process are transmitted first at the end diastole (or end systole) with little motion. At this point, the operator can start the feature point designation operation using the two transmitted frames. During the work, the image transmission unit 12 transmits 8 frames of the concentric phase with the 2 frames. The operator designates coordinates using the 10 frames transmitted so far. When these operations are completed, the transfer of the image transfer (first to 20th frames) in the first section is completed.

  As shown in FIG. 15, it takes an enormous amount of time for all 200 images to be transferred to the external device 20. However, about 10 images can be transferred at high speed. Therefore, the operator can start the feature point specification work quickly, and if the remaining images are sequentially transferred during the operator's work, the time required for the processing can be shortened as a total. As described above, by preferentially transmitting necessary frames in accordance with the operation of the external apparatus, it is possible to reduce the transmission waiting time of the image data and to perform the operation efficiently.

  In the ninth embodiment, the image having the same cardiac phase is transferred after the first two frames are transferred. However, it is not essential to transmit the image having the concentric phase, and it is configured to transmit frames at equal intervals. May be. In addition to volume data reconstruction, when constructing a cardiovascular three-dimensional model using two frames, it is better to apply a method that preferentially transmits two frames with a concentric phase and an imaging angle of about 90 degrees apart. .

(Example 10)
In the tenth embodiment, after the concentric phase image is transmitted first, the image for each section is transmitted in the same manner as the acquisition order. FIG. 16 is a diagram illustrating a frame transmission order according to the tenth embodiment.
The following method is adopted as the order of data processing in volume data reconstruction.

The transmission order determination unit 11 determines the transmission order so that concentric phase frames are transmitted first, and then images for each section are transmitted. Specifically, the first, 20, 40, 50, 70, 100, 130, 150, 180, and 200 frames of the end diastole (or end systole) with little movement are transmitted, and then the section 2 to 19 frames are transmitted. Next, sections 21 to 39 frames are performed, and finally sections 181 to 199 frames are transmitted.

  According to the tenth embodiment, since the frames necessary for specifying the feature points are transmitted first, the operator can start the process before all the frames are transferred, thereby enabling efficient work. .

  According to each configuration described above, since an image necessary for work performed by the external apparatus is preferentially transmitted, the operator does not have to wait until all moving image data is transferred. Thereby, the waiting time until the start of work such as observation / analysis processing can be shortened. In particular, since the cardiovascular three-dimensional construction is assumed to be used during the operation, it is possible to omit the unnecessary waiting time and perform the operation quickly.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Specific examples of modifications are as follows.

  (1) Each function according to the present embodiment can also be realized by installing a program for executing the processing in a computer such as a workstation and developing the program on a memory. At this time, a program capable of causing the computer to execute the technique is stored in a recording medium such as a magnetic disk (floppy (registered trademark) disk, hard disk, etc.), an optical disk (CD-ROM, DVD, etc.), or a semiconductor memory. It can also be distributed.

  (2) In each of the above-described embodiments, the X-ray image of the heart is used for the description. However, the present invention is not limited to the X-ray image but can be applied to other medical images such as an MRI image and an ultrasonic image. In addition, the electrocardiogram signal is not always essential, and the phase of another periodic biological motion (for example, respiratory motion) can be used instead of the cardiac phase.

  (3) In the above embodiment, the image transmission apparatus is integrated with the X-ray diagnosis apparatus. However, the image transmission apparatus having the image data storage unit 10 may be configured separately and independently. For example, an image transmission device may function as an image storage device (image server), transfer an image stored therein to a mobile phone using a wireless line or a public line, and view the image at a destination. It becomes possible.

  In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

The figure which shows the structure of the X-ray diagnostic apparatus provided with the image transmission apparatus which concerns on this embodiment. The figure which shows a cardiac phase. The figure which shows the imaging | photography angle of an X-ray tube. FIG. 3 is a diagram illustrating a frame transmission order according to the first embodiment. The figure which shows the example of a display of the projection image displayed on the screen of an external device. FIG. 10 is a diagram illustrating a frame transmission order according to the second embodiment. FIG. 10 is a diagram illustrating a frame transmission order according to the third embodiment. FIG. 10 is a diagram illustrating a frame transmission order according to the fourth embodiment. The figure which shows the example of a display of the projection image displayed on the screen of an external device. FIG. 10 is a diagram illustrating a transmission order of frames in the fifth embodiment. The figure showing the transmission order of the frame in Example 6 The figure showing the transmission order of the frame in Example 7 The figure showing the transmission order of the frame in Example 8 The figure showing the transmission order of the frame in Example 9 The figure showing the relationship between an image transfer process and an operator's work. The figure showing the transmission order of the frame in Example 10.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... X-ray tube, 2 ... X-ray detector, 3 ... Top plate, 4 ... X-ray control part, 5 ... C arm mechanism, 6 ... C arm / top plate movement control part, 7 ... Electrocardiograph, 8 ... Operation unit, 9 ... system control unit, 10 ... image data storage unit, 11 ... image reconstruction processing unit, 12 ... monitor, 13 ..., 14 ..., NW ... network, 20 ... external device.

Claims (5)

A storage unit for storing data of a plurality of projection images related to the subject collected in order;
An image transmission apparatus comprising: a transmission unit configured to transmit the plurality of projection images to an external apparatus in an order different from the order.   The image transmission apparatus according to claim 1, wherein the order is determined such that a cardiac phase obtained from electrocardiogram information of the subject is given priority from a projection image in a specific period.   The image transmission apparatus according to claim 1, wherein the order is determined based on an imaging angle of each of the plurality of projection images.   The image transmission apparatus according to claim 1, wherein the order is determined by thinning out the plurality of projection images every predetermined photographing time.   The image transmission apparatus according to claim 1, wherein the order is determined based on operation information for each of the plurality of projection images.

Images