JP4128773B2 - X-ray computed tomography equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray computed tomography apparatus that reconstructs and displays tomographic image data based on projection data collected from a subject.
[0002]
[Prior art]
Conventionally, for example, an X-ray tube and an X-ray detector arranged so as to face each other in the gantry rotating unit are rotationally driven, and an X-ray is intermittently or continuously applied to a subject inserted in the gantry rotating unit. A so-called third-generation X-ray computed tomography apparatus that captures a tomographic image of a subject by exposing the object is known.
[0003]
Here, in order to accurately capture a tomographic image of a desired part of the subject with an X-ray computed tomography apparatus, the operator may, for example, “please hold your breath and stop” Please do not give instructions such as “Please do not” to suppress the body movement of the subject and adjust the posture. Such an inspection instruction is made by a human voice through a microphone.
[0004]
However, in many cases, the test instructions given in the test are the same for each subject, and it is sufficient if the number of subjects is small. On the other hand, a great burden is applied.
[0005]
For this reason, some conventional X-ray computed tomography apparatuses are provided with a function of automatically issuing an examination instruction for imaging on a subject placed on a bed. In the voice database, sample data of various voice signals such as “please breathe out and stop” and “please hold your breath” are stored. By designating appropriate audio data, it is substituted for real voice instructions.
[0006]
However, according to this method, the operator needs to select and specify the voice data each time during the examination. The operator must perform various tasks such as scan control, scan operation status monitoring, and subject status monitoring during the examination. In addition, it is extremely difficult to select and specify audio data. Cumbersome and burdensome. Although it is conceivable that the selection and designation of audio data is completed in advance, the amount of work is not reduced compared to the former case.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to reduce the burden of various instruction operations on a subject and standardize instruction contents in an X-ray computed tomography apparatus.
[0008]
[Means for Solving the Problems]
The present invention relates to an X-ray computed tomography apparatus that reconstructs and displays tomographic image data based on projection data collected from a subject, and a method for coping with the precautions or feeling when using a contrast agent A database for storing data of a plurality of messages including the message, an input device for inputting a command from an operator, a scheduler for determining an inspection schedule according to the command input via the input device, and the determination The data of at least one message is selectively read out from the database based on the inspection schedule and whether or not the use of contrast medium is set, and the read message is edited according to the number of scans and the scan time An editing unit that converts the edited message data into an audio signal or a video signal And an output unit for outputting Te.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. The present embodiment relates to a two-dimensional array type radiation detector and an X-ray computed tomography apparatus (X-ray computed tomography apparatus) equipped with the radiation detector. In the X-ray computed tomography apparatus, a rotation / rotation (ROTATE / ROTATE) type in which an X-ray tube and a radiation detector are rotated as one body, and a number of detection elements are arrayed in a ring shape. There are various types such as a fixed / rotation (STATIONARY / ROTATE) type in which only the X-ray tube rotates around the subject, and the present invention can be applied to any type. Here, the rotation / rotation type that currently occupies the mainstream will be described.
[0010]
In addition, in order to reconstruct one volume of voxel data (which constitutes one volume data) (or one tomographic image) (both will be described later), a projection of about 360 ° around the subject is performed. The projection data corresponding to about 210 to 240 ° is also required for the data even in the half scan method. The present invention can be applied to any method. Here, a description will be given assuming that one volume of voxel data (or one tomographic image) is reconstructed from the projection data of about 360 ° of the general former.
[0011]
In addition, the mechanism for converting incident X-rays into electric charges is based on an indirect conversion type in which X-rays are converted into light by a phosphor such as a scintillator and the light is further converted into electric charges by a photoelectric conversion element such as a photodiode. The generation of electron-hole pairs in semiconductors and their transfer to the electrode, that is, the direct conversion type utilizing a photoconductive phenomenon, is the mainstream. Any of these methods may be employed as the X-ray detection element, but here, the former indirect conversion type will be described.
[0012]
The tomographic image is a cross-sectional display of a tissue having a certain thickness, and the thickness of the tissue cross-section is referred to as a slice thickness. X-rays spread radially from the focal point of the X-ray tube, pass through the subject, and reach the X-ray detector. Therefore, the thickness of the X-rays increases as the distance from the X-ray tube focus increases. Conventionally, the thickness of the X-ray on the rotation center axis is defined as the slice thickness. Here, in accordance with the convention, the thickness of the X-ray on the rotation center axis is referred to as a slice thickness. This is also true for the width of the detection element in the slice direction. That is, in the expression of a detection element having a sensitive width corresponding to a certain slice thickness, the sensitive width is actually wider than the slice thickness, specifically, with respect to the distance between the X-ray focal point and the rotation center axis. In actuality, it needs to be designed wider than the slice thickness according to the ratio of the distance between the X-ray focal point and the detection element.
[0013]
FIG. 1 is a block diagram showing the configuration of a computed tomography apparatus according to this embodiment. The gantry 100 accommodates a structure required for data collection, such as a rotating ring 102 that is rotationally driven by a gantry driving unit 107, in an interior surrounded by a substantially cylindrical inner housing 129 and a housing 130. The rotating ring receives an application of a high voltage (tube voltage) from the high voltage generator 109 via the slip ring 108 and generates X-rays. The X-ray tube 101 transmits the subject. The incident X-ray detector 103 is mounted to face.
[0014]
A signal (current signal) output from each channel of the X-ray detector 103 is amplified by a data acquisition circuit 104 generally called a DAS (data acquisition system), converted into a voltage signal, and then a digital signal. And sent to the pre-processing device 106 on the fixed side via the non-contact data transmission device 105 using light or magnetism.
[0015]
The pre-processing device 106 corrects non-uniform sensitivity between channels with respect to the input signal, or corrects an extreme decrease in signal intensity or signal dropout due to an X-ray strong absorber, mainly a metal part. Execute the process. Based on the projection data output from the preprocessing device 106, the tomographic image data is reconstructed by the reconstruction device 113 and displayed on the display device 111. A computer device is configured by the host controller 110 and the input device 112 together with the reconstruction device 113 and the display device 111.
[0016]
The computer device further includes a database 125 that stores data of a plurality of messages, an inspection scheduler 124 that determines an inspection schedule according to a command input via the input device 112, and an inspection schedule determined by the inspection scheduler 124. Based on this, at least one message data is selectively read from the database 125, the message editing unit 129 for editing, and the message data edited by the message editing unit 129 is converted into an acoustic signal and output to the inner speaker 121. An inner speaker control unit 133 and an inner display control unit 131 that converts message data edited by the message editing unit 129 into a video signal and outputs the video signal to the inner display 123 are provided.
[0017]
The inner speaker 121 is attached to a part of the gantry 100 where the subject can hear the sound generated from the inner speaker 121 or a place on the wall surface of the imaging room. For example, the inner speaker 121 is attached outside the X-ray irradiation range and in the vicinity of the edge of the inner housing 129. The inner display 123 is attached to a portion where the subject can visually see the image displayed on the inner display 123 or a place where the wall surface of the imaging room is located. For example, the inner display 123 is attached outside the X-ray irradiation range and in the vicinity of the edge of the inner housing 129.
[0018]
By using the inner speaker 121 and the inner display 123, it is possible to automatically transmit various instructions such as examination schedule guidance and breath holding to the subject.
[0019]
2A, 2B, 2C, 3A, and 3B show data of a plurality of messages stored in the message database 125. FIG. Each message constitutes one sentence and is created, for example, as a text file. Since it is a text file, new creation, update, correction, etc. can be made relatively easily on the user side.
[0020]
The examination includes at least one scan that actually irradiates the subject with X-rays and collects data, and is divided into aspects such as prior explanation before the examination, before the scan, after the scan, pause, and completion of the examination. Messages are classified for each of these aspects and stored together with the management code. Symbols “**” in these messages indicate locations where the corresponding text is automatically inserted by the editing unit 129 according to the scan schedule.
[0021]
Next, a message automatic output process together with a series of inspection flows will be described with reference to FIG. First, the subject is placed on the couch top, and is carried into the cylindrical imaging region of the gantry 100 together with the couch (S1), and the slice position is positioned (S2). Next, with the rotation of the X-ray tube 101 stopped, the X-ray is continuously generated, and the top plate is moved at a constant speed while the detector 103 detects X-rays transmitted through the subject. In general, a wide-range transmission X-ray image of a subject called a scanogram is taken (S3). The scanogram is displayed on the display device 111, and the operator inputs an instruction necessary for determining the examination schedule through the input device 112 while viewing the scanogram (S4). For example, imaging method (contrast agent use / non-use), scan conditions (tube voltage, tube current, number of images, scan time, etc.), number of scans, slice position, presence or absence of breath hold during scan, scan pause time, etc. Is set, and the inspection schedule is determined by the inspection scheduler 124 accordingly.
[0022]
When the examination schedule is determined, the message editing unit 129 creates, for example, an examination schedule table as shown in FIG. 8 according to the examination schedule, and creates a message for prior explanation (S5).
[0023]
FIG. 5 shows a message creation procedure for prior explanation. First, the message data of the code A1 is read as an introduction part common to all inspections (S101). This message A1 is provided with insertion positions of the number of scans (the number of scans performed during the inspection), the scan time (the time width required for each scan), and the inspection time (the time width from the start to the end of the inspection). Then, the editing unit 129 inserts texts corresponding to these at the respective insertion locations according to the examination schedule (S102). Here, it is assumed that the number of scans is 3, the scan time is 20 seconds, and the inspection time is 2 minutes.
[0024]
Next, the editing unit 129 selectively reads the message of the code A2-1 and the message of the code A2-2 according to the presence or absence of breath holding during the scan (S103) (S104, S105). When breath hold is set during scanning by the operator, the message of code A2-1 relating to the description of breath hold is selected, and when breath hold is not set, code A2-2 relating to the attention of breathing during scanning Message is selected.
[0025]
Next, the message data of the code A3 is read as a common message related to attention related to body movement during scanning (S106). Then, it is determined whether or not a pause is set (S107). When the pause is set, the message data of the code A4 relating to the pause explanation is read (S108), and the pause set at the insertion position therein is read. Time is inserted (S109). When the pause is not set, steps S108 and S109 are skipped, and the message regarding the pause is omitted.
[0026]
Next, it is determined whether or not the use of the contrast medium is set (S110). When the use of the contrast medium is set, the message data of the code A5 regarding the precautions when using the contrast medium is read (S111). When not in use, step S111 is skipped and the message is omitted.
[0027]
Further, the common message data of the code A6 relating to the coping method in the case of feeling worse and the message data of the code A7 relating to the end of the preliminary explanation are read (S112, S113), and finally all the read message data are sequentially Connected to complete one sentence (S114).
[0028]
Returning to FIG. When the pre-explained message is completed, the message data is sent to the inner display control unit 131 and the inner speaker control unit 133. The inner display control unit 131 converts the message data into a video signal, and as shown in FIG. The information is displayed on the display 123 together with the inspection schedule table, and the inner speaker control unit 133 converts the message data into an acoustic signal and outputs the sound from the inner speaker 121 as shown in FIG. 6 (S6).
[0029]
When the preliminary explanation is finished and the operator presses the inspection trigger button, the inspection is started (S7). The inspection scheduler 124 proceeds with the inspection in accordance with the inspection time schedule with the timing at which the inspection trigger button is pressed as an opportunity. According to this progress, time data indicating the elapsed time is sent to the inner display control unit 131, and the inner display control unit 131 in accordance with the time data shows an inspection schedule table for the inner display 123 as shown in FIGS. 9 (a) and 9 (b). The progress of the inspection is indicated by a change in display mode such as color (S8).
[0030]
For example, five seconds before the scan (S9), the message editing unit 129 controls the message data of the code B1 or B2 corresponding to the pre-scan aspect according to the presence or absence of breath holding under the control of the examination scheduler 124. The data is selectively read, the scan time is inserted at the insertion position, the pre-scan message data is completed, and the data is sent to the inner display control unit 131 and the inner speaker control unit 133. The inner display control unit 131 converts the pre-scan message data into a video signal and displays it on the inner display 123 together with the inspection schedule table. The inner speaker control unit 133 converts the pre-scan message data into an audio signal. As shown in FIG. 6, sound is output from the inner speaker 121 (S10).
[0031]
When the scan is finished (S11), the message editing unit 129 selectively reads the message data of the code C1 or C2 corresponding to the post-scanning situation according to the presence or absence of breath holding under the control of the examination scheduler 124. The data is sent to the inner display control unit 131 and the inner speaker control unit 133. The inner display control unit 131 converts the scanned message data into a video signal and displays it on the inner display 123 together with the inspection schedule table. The inner speaker control unit 133 converts the scanned message data into an acoustic signal. As shown in FIG. 6, sound is output from the inner speaker 121 (S12).
[0032]
The inspection scheduler 124 determines whether or not there is a pause after the scan (S13). When the pause is set, the message editing unit 129 controls the message data of the code D corresponding to the pause phase under the control of the inspection scheduler 124. Read, insert a pause time at the insertion location, complete pause message data, and send the data to the inner display controller 131 and the inner speaker controller 133. The inner display control unit 131 converts the pause message data into a video signal and displays it on the inner display 123 together with the inspection schedule table. The inner speaker control unit 133 converts the pause message data into an acoustic signal. 6, sound is output from the inner speaker 121 (S 14).
[0033]
The series of processes in steps S8 to S14 described above is repeated until the inspection is completed (S15). When the inspection is ended, the message editing unit 129 creates message data for the end of the inspection (S16). First, code E1 for announcement of completion of examination common to all examinations and message data of code E2 concerning precautions after examination are read in order, and further code E3-1, concerning action instruction of the subject after examination. One of the message data E3-2 and E3-3 is selectively read in accordance with the operator's instruction, and all the read message data are connected in order to complete one sentence.
[0034]
The test end message data is sent to the inner display control unit 131 and the inner speaker control unit 133. The inner display control unit 131 converts the message data into a video signal and displays it on the inner display 123 together with the test schedule table. In addition, the inner speaker control unit 133 converts the message data into an acoustic signal and outputs the sound from the inner speaker 121 as shown in FIG. 6 (S17).
[0035]
As described above, according to the present embodiment, when an inspection schedule is created, a message is automatically output in each of the prior explanation, the pre-scan, the post-scan, the pause, and the inspection end. Moreover, it is edited into an appropriate message according to the inspection schedule. Accordingly, various instruction work burdens on the subject by the operator are reduced.
[0036]
(Modification)
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Furthermore, the above embodiment includes various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, some constituent requirements may be deleted from all the constituent requirements shown in the embodiment.
[0037]
【The invention's effect】
According to the present invention, in an X-ray computed tomography apparatus, it is possible to reduce the burden of various instruction operations on a subject and standardize instruction contents.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a computed tomography apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram showing message data of each aspect stored in the message database of FIG. 1, before explanation, before scanning, and after scanning.
FIG. 3 is a view showing message data of each aspect of suspension and inspection termination stored in the message database of FIG. 1;
FIG. 4 is a flowchart showing the operation of the embodiment.
FIG. 5 is a flowchart showing a detailed procedure of step S5 for editing a pre-explanation message in FIG. 4;
FIG. 6 is a diagram showing a voice message automatically output in each aspect in the present embodiment.
FIG. 7 is a view showing a text message displayed on the inner display together with an examination progress table in the present embodiment.
FIG. 8 is a diagram showing an example of an inspection schedule table displayed on the inner display in the present embodiment.
FIG. 9 is a diagram showing a change in the display form of the examination schedule table according to the examination progress in the present embodiment.
[Explanation of symbols]
100 ... gantry,
101 ... X-ray tube,
102 ... rotating ring,
103 ... X-ray detector,
104: Data collection circuit,
105: Non-contact data transmission device,
106... Pretreatment device,
107 ... gantry drive part,
108 ... slip ring,
109 ... high voltage generator,
110: Host controller,
111... Display device,
112... Input device,
113 ... Reconstruction device,
121 ... inner speaker,
123 ... inner display,
124... Scan scheduler,
125 ... message database,
129: Message editing section,
131 ... inner display control unit,
133: Inner speaker control unit.

Claims (3)

In an X-ray computed tomography apparatus for reconstructing and displaying tomographic image data based on projection data collected from a subject,
A database that stores data for multiple messages, including precautions when using contrast agents or messages about how to deal with feeling unwell ,
An input device for inputting commands from the operator;
A scheduler for determining an inspection schedule according to a command input via the input device;
Based on the determined examination schedule and whether or not the use of a contrast medium is set, at least one message data is selectively read from the database, and the read message is read as the number of scans or scan time. Editing section to edit according to ,
An X-ray computed tomography apparatus comprising: an output unit that converts the edited message data into an audio signal or a video signal and outputs the signal.   The X-ray computed tomography apparatus according to claim 1, wherein the plurality of messages stored in the database are classified according to an examination situation. The X-ray computed tomography apparatus according to claim 2 , wherein the inspection phase includes an advance explanation phase, a scan operation start phase, a scan operation end phase, and an inspection end phase.

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