JPS6382629A - Ct apparatus - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a CT apparatus that connects a plurality of CT apparatuses to a common transmission path and performs reconfiguration.

(Prior Art) A CT apparatus is composed of a large number of devices, which are interconnected in a complicated manner. For example, a single X-ray CT device contains an X-ray tube that emits X-rays from around the subject's tomographic image, and an X-ray detector that detects the X-ray beam that has passed through the subject. , a processing device that converts the analog signal from the X-ray detector into digital (G) and then reconstructs the tomographic image using an arithmetic circuit, a display device that displays the processed tomographic image, and a memory that stores the tomographic image. There are a large number of devices, such as devices and editing devices that edit stored tomographic images.

These devices are precisely engineered to provide accurate diagnosis quickly. Among these, the process of reconstructing tomographic images is the most important and requires extremely high accuracy.

(Problems to be Solved by the Invention) As described above, X-ray CT apparatuses are very expensive and only one or two are installed in each hospital. However, since this X-ray CT device provides reliable findings for diagnosing patients, the demand for it is increasing and it is becoming cheaper.

For this reason, one large hospital has two to five X-ray CT apparatuses. However, since one CT apparatus is comprised of many components as described above, it requires a very large space, and the number of CT apparatuses that can be installed in one hospital is limited.

Furthermore, the process of reconstructing tomographic images, as will be the case in the future, must be performed with high accuracy and handle a large amount of data. For example, if the number of data points is 512 channels and the detection angle is 1 degree, a simple calculation would require 512×365=180,000 or more calculations. Therefore, high-speed and highly accurate reconstruction calculations are required.

Therefore, an object of the present invention is to quickly obtain a tomographic image from data detected by a CT device.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a detection device that detects a signal obtained from a cross-sectional portion of a subject and outputs a signal corresponding to the detected signal as a detection signal; a first reconstruction calculation means for converting the detection signal into first tomographic image data of the cross-sectional portion; and a common data transmission path to which a plurality of the detection devices can be connected, and the detection signal is transmitted to the common data transmission path. and a transfer means connected to the transfer means that converts the detection signal into second tomographic image data of the cross section, and furthermore, the conversion is spatially smaller than the conversion of the first reconstruction calculation means. A second reconstruction calculation means for performing calculations with high resolution is connected to the path of the detection signal from the detection device to the second reconstruction calculation means, and the detection signal from the detection device is temporarily storage means for storing; and the storage means is used to delay the detection data and control the detection data from the plurality of detection devices to execute the second reconstruction calculation means at different times respectively. the second tomographic image data which has been transformed by the control means and the second reconstruction means is transmitted as the second tomographic image of the cross section through the common data transmission path; The first tomographic image data obtained by the reconstruction means constitutes a CT apparatus including a display means for displaying each of the tomographic images as a first tomographic image of the tomographic section.

(Function) A detection device detects a signal obtained from a cross-sectional portion of the object, and a first reconstruction calculation means converts the signal into first tomographic image data of the cross-sectional portion. a second reconstruction processing means for converting the detection signal sent through the means into second tomographic image data of the cross-sectional portion, and further performing a calculation with a higher spatial resolution than the conversion by the first reconstruction calculation means; the detection data is delayed by a storage means in which the detection signals from the detection devices are temporarily stored, and the detection data from the plurality of detection devices are reconstructed at different times. By controlling the second reconstruction calculating means to be executed, the second tomographic image of the cross section and the first tomographic image of the cross section can be displayed on the display means.

(Example) The CT (computed tomography) device in the present invention is a diagnostic device that obtains a tomographic image of a subject by a reconstruction calculation method, and the diagnostic device includes, for example, an X-ray CT device, a radionuclide CT equipment, ultrasound CTB equipment, MRI
(Magnetic Resonance Imaging) Equipment 1 Particle beam or heavy ion beam CT
There is a device.

Further, the common data transmission path in the present invention may be a medium such as an optical fiber or a coaxial cable, or may be wireless communication.

Therefore, as an embodiment of the present invention, we will take up an X-ray CT device in which an X-ray source and a detector rotate together.
The configuration of the T device will be explained with reference to FIG. 1 and the flow of operation shown in FIG. 2, respectively.

The gantry 1 shown in FIG. 1 includes an X-ray source 2 (for example, an It has a possible mechanism. This rotation mechanism is controlled by a gantry control device 6 connected to the gantry 1.

The Xta beam from the X-ray source 2 is controlled by an X-ray source control device 8 connected to the X-ray source 2.

Further, control of the tomographic position of the subject 3 is controlled by a table control device 7 connected to the table 5.

These devices 6, 7, and 8 are controlled by an imaging control device 9. The X-ray beam that has passed through the subject 3 is converted into an electrical signal corresponding to the amount of each beam by the detector group 4 and output to the data acquisition device 10 . Data collection device 1
0 converts the electric signal sent from the detector group 4 into a digital signal, and also has correction processing such as reference correction, offset correction, and speed correction. Through this digital conversion, electrical signals sent while the detector group 4 is rotating are sequentially converted and output as detection signals to the data processing device 11.

The data processing device 11 is connected to the first correction means 17 and the first reconstruction calculation means 18, and performs reconstruction based on the detection signal from the data acquisition device 10, and the first The tomographic data is output to the image display device rIt14. The first correction means 17 performs scatter correction, arc interpolation, and log interpolation.

Wedge correction and calibration correction are performed.

On the other hand, the image display device 14 displays tomographic data sent from the data processing device 11 as a tomographic image of the subject 3.

In the photographing control device 15, the same tomographic image as that displayed on the image display device 14 is displayed as photograph 1. In addition, in the data processing device 11, indexes such as the ID of the subject 3, the examination site, and the date of examination 1 are inputted from the input device 13.
It is sent to the storage device 12 together with a detection signal corresponding to the index.

In the storage device 12, the detection signals sent from the data processing device 11 are sequentially stored, and the index from the input device @13 is also stored.

The transfer means has a node 16 and one common data transmission path,
Information between the nodes 16 is exchanged via the common data transmission path 19.

Node 16 connects each node 1 through one common data transmission path.
It plays the role of an interface that is controlled so that mutual information exchange with the zero-emission device 23 connected to 6, a terminal device (not shown), and devices corresponding to a total of f3 aircraft is performed smoothly. One common data transmission path is node 16
This is the transmission path through which information between the two is transferred.

The reconstruction calculation means 20 corrects the detection data from the data processing device 11 using the correction means 22, and then performs reconstruction calculation of the detection data. Second tomographic data is obtained from the calculation result. The second reconstruction calculation means 20 has higher spatial resolution and higher density resolution than the first reconstruction calculation means 18, and can obtain tomographic images that are advantageous for diagnosis. This reconstruction operation performs a convolution operation and a pack projection operation. At this time, methods for changing the spatial resolution and density resolution of the two reconstruction calculation means 18 and 20 include, for example, a method of changing the number of detected data and a method of changing the calculation accuracy. For example, methods to change the number of detected data include:
The second reconstruction calculation means 20 performs calculations using all the data detected by the detector 4 (for example, 512 channels).
The reconstruction calculation means 18 performs calculations using half of the data detected by the detector 4. - For example, when data for 256 channels is selected from the 512-channel detector group 4 arranged in a column, every other detector is taken out.

Furthermore, data detected at a relatively double detection angle may be used as calculation data.

When using a method of changing calculation precision, the calculation precision of the first reconstruction calculation means 18 may be lowered compared to that of the second reconstruction calculation means 20.

Further, the second correction means 22 performs scatter correction.

Performs arc interpolation, log interpolation, wedge correction, and calibration correction.

The first correction means 17 performs correction with approximately the same accuracy as the second correction means 22 or with a lower accuracy of 1 degree.

In this way, by using a plurality of reconstruction calculation means 18.20 and correction means 17.22 and operating both 18 and 20 or 17 and 22 in parallel to perform reconstruction, it is possible to perform a quick diagnosis. becomes.

In other words, in order to improve performance, a large number of arithmetic operations must be performed. Further, by providing the second reconstruction calculation means 20 and the correction means 22 at one or several places and calculating the reconstruction processing from a plurality of CT apparatuses, for example, in a time-sharing manner, more effective processing can be performed. The number of IC arithmetic processing devices that require a large number of arithmetic operations can be significantly reduced.

Furthermore, by allowing the data processing device 11 to perform correction and reconfiguration without going through the common data transmission path 19, it is possible to prevent the failure of the common data transmission path 19, the node 16, or the second reconfiguration calculation means 20. It is possible to provide a CT apparatus that can be used even in the case of emergency patients.

Furthermore, by connecting the first correction means 17 and the reconstruction calculation means 18 to another node 16 (not shown) and performing calculations through a common data transmission path, the load on the data processing device 11 can be reduced and space can be reduced. . By exchanging information with small hospitals using a common data transmission path using telephone lines, optical fibers, and radio, small-sized CT devices can also be installed in small hospitals and clinics. As a result, there is no need to transport seriously injured Tadatsu to a large hospital.

After the second reconstruction calculation is performed, the second tomographic data is transferred to the data processing device 11 from which it was sent, but if the common data transmission path 19 is being used by another node 16. In this case, after memorizing it in the memory neck 21,
After the common data transmission path 19 is free, the storage device 2
Read from 1 and output.

Further, the storage device 21 may be provided before the second reconstruction calculation means 20. Thereby, even if the second reconstruction calculation means 20 temporally overlaps with the reconstruction processing of other CT apparatuses, it is possible to reconstruct a plurality of CT apparatuses by temporarily storing the detected data in the storage device.

Such a storage device may be included in the 12 storage devices, or may be connected to another node 16 (not shown). By storing the detected data in the storage device 12, even if the reconstruction by the second reconstruction calculating means 20 fails, the reconstruction can be performed again.

Furthermore, the second reconstruction calculation means 20 may use detection data from a CT device of the same model or a different model (for example, the emission CT device 23).

Next, the operation flow of the CT apparatus shown in FIG. 1 will be explained with reference to flowchart 1 in FIG. 2.

First, the subject 3 is placed on the table 5 and the table is moved by the table controller 7 so that the cross section of the subject 3 to be sectioned coincides with the plane formed by the X-ray source and detector group 4 ( 30).

Next, the ID of the subject 3, the test site, and the tester.

An item such as an inspection part is input from the input device 13 as an item of a new house image (31). Items sent from the common data transmission path 19 in advance may be input to this input means. When information about the subject 3 is transferred through the common data transmission path 19, an input device (not shown) is connected to the common data transmission path 19. The table moving means (
30) and the input means (31) may be executed first or at the same time.

When these means (30) and (31) are completed, the X-ray source 2 and the detector group 4 work together to rotate around the subject, and the X-ray beam from the X-ray source 2 is directed toward the subject 3. and then exposed to
The X-ray beam is detected by the detector group 4 (32).

Based on the detection data obtained by (32), the first
The configuration process is executed by the reconstruction calculation means 18 (33). The detection data may be corrected by the correction means 17 between the execution of (33) and the execution of (32). The thus obtained tomographic image of the subject 3 is displayed on the image display device 14 together with the data inputted using the input device 13 (34). In parallel with these (33) and (34), the detection data is stored in the storage device 1.
2 (35). Next, in order to output the stored data to the common data transmission path 19, the node 16 is inquired about the state of the transmission path 19 (36).

As a result of the inquiry, if the transmission line 19 is available, the stored data is read out and transferred to the node 16 (3
8). If the result of the inquiry is not usable, it is retained until it becomes available (37). The detection data read out from the storage device 12 is immediately subjected to second reconstruction by the reconstruction calculation means 20, but the reconstruction calculation means 20 is
3, it waits until the calculation means 20 becomes available in the storage device W112 or 21. As soon as it is determined that the reconstruction calculation means 20 can be used, the correction means 22 performs the second correction and then executes the second reconstruction calculation (39). The second reconstruction calculation is corrected by the correction means 22 before its execution, and then the calculation is performed more accurately and faster than the first reconstruction calculation means. The second tomographic image obtained in this way is returned to the data processing device 11. At this time, if another device is using the common data transmission path 19, the storage device 2
1 and is saved temporarily (41). Therefore, by providing memory for at least two images in the storage device 21, the second (2) configuration calculation can be executed efficiently. The data of the second tomographic image obtained in this manner is displayed as a second tomographic image on the image display device 14 via the data processing device 11.

By executing such second calculation means during the time when the patient is transferred to the table 5, the time when the tomographic position is adjusted, and the time when the X-ray tube cools down to a predetermined temperature, the reconstruction calculation means can be used more effectively. can do.

Needless to say, it will also greatly contribute to local medical activities. In addition, the CT wave device can be made smaller, the detected data can be immediately reconstructed, and highly accurate tomographic images can be viewed later.

[Effects of the Invention] As described above, according to the present invention, a tomographic image can be quickly obtained from data detected by a CT wave device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the CT wave apparatus according to the present invention, and FIG. 2 is a flow chart 1- showing the flow of operation of the embodiment of the CT wave apparatus according to the present invention. 18...First reconstruction calculation means 20...One second reconstruction calculation means...Common data transmission path

Claims (1)

[Scope of Claims] A detection device that detects a signal obtained from a cross-sectional portion of a subject and outputs a signal corresponding to the detected signal as a detection signal, and converts the detection signal into first tomographic image data of the cross-sectional portion. a first reconstruction calculation means for converting; a transfer means having a common data transmission path to which a plurality of the detection devices can be connected; a transfer means for transferring the detection signal through the common data transmission path; and a transfer means connected to the transfer means, A first processing unit that converts the detection signal sent through the transfer means into second tomographic image data of the cross-sectional portion, and that the conversion has a higher spatial resolution than the conversion performed by the first reconstruction calculation means. a storage means connected to the path of the detection signal from the detection device to the second reconstruction calculation means, and in which the detection signal from the detection device is temporarily stored; a control means for delaying the detection data using the storage means and controlling the detection data from the plurality of detection devices so that the second reconstruction calculation means is executed at different times for each of the detection data; and the second tomographic image data obtained by the second reconstructing means are passed through the common data transmission path as a second tomographic image of the cross section, and the second tomographic image data obtained by the first reconstructing means The tomographic data of the first cross-section
1. A CT apparatus comprising: display means for displaying each as a tomographic image.