JP2010005192A - Medical imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical imaging apparatus which reduces erroneous imaging when imaging while stopping breathing. <P>SOLUTION: The medical imaging apparatus provided with a display device for performing display for guiding breathing and breath-stopping operation of a patient is provided with: a measuring instrument for measuring a period passing from the start of imaging; a determination apparatus which determines whether a residual time of stopping breathing amounts to a predetermined time on the basis of the measurement result obtained by the measurement instrument; and a control device which controls the display device on the basis of the determination result of the determination apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a medical image photographing apparatus, and more particularly to a medical image photographing apparatus that can reduce photographing errors during breath-hold photographing.

  When a subject is imaged using a medical imaging apparatus, imaging may be performed while the subject holds his / her breath to prevent deterioration of image quality due to movement of an organ accompanying breathing of the subject. As a medical image photographing apparatus provided with an instruction display device for displaying instructions for instructing the breathing or breath holding operation of the subject so that the subject can appropriately hold the breath during such breath holding photographing, for example, Patent Document There is one. Patent Document 1 discloses a CT apparatus that displays figures and numbers for instructing breathing and breath-holding operations on an indication display provided in a window portion of a positioning light for irradiating a positioning light beam for a subject. It is disclosed. The instruction display displays the remaining imaging time so that the subject can know the remaining imaging time.

JP-A-9-192123

  By the way, while the display of the remaining time of imaging is accurately known for the subject, it causes psychological suppression such as “Can the displayed time be kept breathing?”. Also, if the cold subject stops breathing during imaging, the imaging time up to that time is wasted and an imaging error occurs.

  Therefore, an object of the present invention is to provide a medical image photographing apparatus that can suppress psychological suppression of a subject and reduce photographing errors during breath-hold photographing.

  As a result of investigations by the inventors regarding breath-holding photography, it is more likely that the subject will hold the breath holding time when the remaining time is displayed when the predetermined remaining time is reached rather than displaying the remaining time immediately before the start of photographing. It was found that it was possible to suppress shooting mistakes caused by stopping. This is because if the subject knows the scheduled imaging time, that is, the breath holding time at the start of imaging, the subject may give up from before the imaging when he / she feels it is difficult to keep holding his breath during the imaging time. It seems to be derived from a certain thing. On the other hand, if you start displaying the remaining time in the middle after the start of imaging, you can make the subject think, “Because you have endured so far, let's endure the remaining time rather than hold your breath by re-imaging” It seems that shooting errors can be reduced.

  Based on the above examination results, in order to solve the above-described problems, the present invention is a medical image photographing apparatus provided with an instruction display device for displaying instructions for instructing the breathing and breath holding operations of a subject. A measuring device that measures an elapsed time from the start of imaging, a determination device that determines whether or not a remaining breath holding time has reached a predetermined time based on a measurement result of the measuring device, And a control device for controlling the display device based on the determination result.

  According to the present invention, psychological suppression of the subject can be suppressed, and imaging mistakes during breath-hold imaging can be reduced.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, the same reference numerals are given to the constituent elements having the same functional configuration, and redundant description will be omitted. In the following description, an X-ray CT apparatus is taken as an example of a medical image diagnostic apparatus, but the present invention is not limited to the X-ray CT apparatus, and may be applied to, for example, a magnetic resonance imaging apparatus.

  FIG. 1 is an overall configuration diagram of an X-ray CT apparatus 1 to which the present invention is applied. This apparatus includes a scan gantry unit 100 and an operation console 120.

  The scan gantry unit 100 includes an X-ray tube 101, a rotating disk 102, a collimator 103, an X-ray detector 106, a data collection device 107, a bed 105, a gantry control device 108, a bed control device 109, An X-ray control device 110. The X-ray tube 101 is an apparatus that irradiates a subject placed on a bed 105 with X-rays. The collimator 103 is a device that controls the irradiation range of X-rays emitted from the X-ray tube 101. The X-ray detector 106 is a device that detects the X-rays that are disposed to face the X-ray tube 101 and pass through the subject. The rotating disk 102 includes an opening 104 through which a subject placed on a bed 105 enters, and is equipped with an X-ray tube 101 and an X-ray detector 106, and rotates around the subject. The X-ray detector 106 includes a plurality (eg, 1000) of detection elements in the rotation direction (also referred to as channel direction) of the rotating disk 102. Further, when the X-ray detector 106 has a plurality of detection elements arranged in the channel direction as one row, this row is arranged in multiple rows (for example, 64 rows) in the rotation axis direction (also referred to as slice direction) of the rotating disk 102. It may be good. The data collection device 107 is a device that converts the X-rays detected by the X-ray detector 106 into a predetermined signal. The gantry control device 108 is a device that controls the rotation of the rotary disk 102. The bed control device 109 is a device that controls the vertical movement of the bed 105. The X-ray control device 110 is a device that controls the output to the X-ray tube 101.

  The console 120 includes an input device 121, an image arithmetic device 122, a display device 125, a storage device 123, and a system control device 124. The input device 121 is a device for inputting a subject's name, examination date and time, imaging conditions, and the like, specifically a keyboard, a pointing device, and the like. The image calculation device 122 is a device that performs calculation processing on measurement data sent from the data collection device 107 and performs CT image reconstruction. Specifically, a CPU (Central Processing Unit) that executes calculation processing or a dedicated processing device It is an arithmetic circuit. The display device 125 is a device that displays the CT image created by the image calculation device 122, and specifically, is a CRT (Cathode Ray Tube), a liquid crystal display, or the like. The storage device 123 is a device that stores data collected by the data collection device 107 and image data of a CT image created by the image calculation device 122, and is specifically an HD (Hard Disk) or the like. The system control device 124 is a device that controls these devices, the gantry control device 108, the bed control device 109, and the X-ray control device 110. The system control device 124 includes a current time acquisition device. The current time acquisition device is a device that acquires the current time. Specifically, the current time acquisition device is a device that acquires time from a clock or a radio clock or the like existing on a network to which the console 120 is connected.

  The X-ray tube 101 is controlled by the X-ray control device 110, and emits X-rays based on imaging conditions (X-ray tube voltage, X-ray tube current, etc.) input from the input device 121. The X-ray detector 106 detects X-rays irradiated from the X-ray tube 101 and transmitted through the subject with each detection element. The rotating disk 102 is controlled by the gantry control device 108 and rotates based on imaging conditions (scanning speed, etc.) input from the input device 121. The bed 105 is controlled by the bed control device 109 and operates based on the imaging conditions (such as a helical pitch) input from the input device 121.

Projection data from various directions (for example, 1000 directions) is collected by the data collection device 107 by irradiating and detecting X-rays while rotating the rotating disk 102 around the subject. The amount of projection data collected when rotating the rotating disk 102 is, for example, 1000 detection elements of the X-ray detector 106, 64 columns, and 1000 projections per rotation If the dynamic range of the detection element is 20 bits, the capacity will be 160MB. The projection data collected by the data collection device 107 is sent to the image calculation device 122. The image calculation device 122 reconstructs the projection data and generates a CT image. The reconstructed CT image is displayed on the display device 125, and is stored in the storage device 123 as image data together with the imaging conditions.
FIG. 2 is an explanatory diagram when the scan gantry unit 100 is viewed from the side, and shows an example of an attachment position of the instruction display device 201. FIG. In this example, three of the indication display devices 201a to 201c are provided in the scan gantry unit 100. The indication display device 201a is provided on one of the tapered wall surfaces of the opening 104, and the indication display device 201b is provided in the opening 104. The instruction display device 201c is positioned on the other of the tapered wall surfaces of the opening 104 at the upper part of the peripheral surface. In this example, three instruction display devices 201 have been described. However, the number of instruction display devices 201 is not limited to three as long as the display device 201 is provided so as to be easily recognized by the subject. Further, it is not always necessary to light all of the plurality of instruction display devices 201, and only the instruction display device at a position that is easy to see for the subject may be selectively lit according to the position of the head of the subject. By selectively lighting the instruction display device according to the position of the subject's head, the instruction display device to be watched is clarified for the subject, and the power consumption of the X-ray CT apparatus can be reduced. it can.

  FIG. 3 is a diagram for explaining the instruction display device 201. The instruction display device 201 includes a stepwise display unit 211 for indicating the remaining time until the start of breath holding and the progress of photographing, and a numerical value display unit 212 for indicating numerical values. The stepwise display unit 211 and the numerical value display unit 212 are configured using an LED (Light Emitting Device), an organic EL (Electro-Luminescence) display, a liquid crystal display, and a plasma display. Although the stepwise display unit 211 shown in FIG. 3 shows a display example of four steps, the number of steps is not limited to four, and may be another number of steps. Further, the stepped display unit 211 is not limited to the bar graph shown in FIG. 3, and may be a pie chart having the number of steps in the circumferential direction, for example. In addition, by lighting all the lamps of the staged display unit 211 in a different color from that used for the staged display, it indicates that X-ray irradiation is in progress and that the subject may breathe easily. It may be.

  FIG. 4 is a diagram showing the flow of operation. Hereinafter, each step will be described.

(Step S401)
The system controller 124 captures the imaging time based on the imaging conditions input by the operator via the input device 121, that is, the scanning time, the number of scans, the scanning range, the bed feeding speed, the helical pitch, etc. Calculate the running time Tscan.

(Step S402)
Imaging based on an imaging start instruction input by the operator via the input device 121, that is, X-ray irradiation from the X-ray tube 101 while rotating the rotating disk 102 and projection by the X-ray detector 106 and the data acquisition device 107 Prior to the start of data collection, the system control device 124 causes the instruction display device 201 to display a breath holding instruction. A method for displaying a breath holding instruction will be described later. In this step, only a breath holding instruction is displayed, and the remaining photographing time is not displayed. The system control device 124 acquires and records the time Tstart at the start of shooting from the current time acquisition device.

(Step S403)
The system control device 124 determines whether or not the remaining photographing time has reached a predetermined time (for example, 10 seconds). Whether or not the predetermined time has been reached is determined based on the imaging time Tscan calculated in step S401, the imaging start time Tstart recorded in step S402, and the current time Tpresent as a predetermined time Tth. Sometimes it is done by

Tth ≧ Tscan − (Tpresent − Tstart)… Equation (1)

That is, when the expression (1) is satisfied, the system control device 124 determines that the predetermined time has been reached. If it is determined that the remaining photographing time has not reached the predetermined time, the process returns to step S403, and if it is determined that the remaining time has reached, the process proceeds to step S404. During this step S403, the instruction display device 201 only displays a breath holding instruction. In addition, the predetermined time set in advance may be set to an appropriate value for each medical facility, or may be set to an appropriate value for each subject.

(Step S404)
The system control device 124 causes the instruction display device 201 to display the remaining photographing time. How to display the remaining time will be described later.

(Step S405)
The system control device 124 determines whether or not shooting has been completed. If the shooting has not been completed, the process returns to step S404. If the shooting has been completed, the process proceeds to step S406.

(Step S406)
The system control device 124 displays on the instruction display device 201 that the imaging has been completed and informs the subject that breathing can be performed easily.

  The above flow of operations prevents the subject from feeling that “it is difficult to keep breathing during the imaging time” at the start of imaging, and suppresses psychological suppression of the subject, thereby preventing imaging errors during breath-holding imaging. Can be reduced.

  A display example of the breath holding instruction in the next step S402 will be described with reference to FIG. When the subject is in a state where the subject can breathe easily, all of the stepped display units 211 are lit in green, for example. As the shooting start time approaches, the lamps are turned off sequentially from the end, and all of the stepped display units 211 are lit in orange, for example, when shooting starts. Alternatively, the number of remaining time until the start of photographing may be counted down on the number display unit 212, or the breath holding instruction by the stepwise display unit 211 and the count down display of the number display unit 212 may be performed simultaneously. Since the countdown display until the start of imaging is performed, the subject can easily start holding his / her breath at his / her own timing, and imaging mistakes during breath-holding shooting can be reduced.

  Next, display examples of the remaining photographing time in step S404 will be described with reference to FIGS.

  FIG. 6 shows an example in which the display of the remaining time until the end of breath holding is linearly changed after the breath holding time reaches a predetermined remaining time. After the start of photographing, until the breath holding time reaches a predetermined remaining time, the display of the stepwise display unit 211 is not changed, for example, all the lamps are lit in orange. When the shooting proceeds and the remaining shooting time reaches a predetermined time, the lamps are turned off sequentially from the end. At this time, the turn-off speed is constant, and the stepped display unit 211 changes linearly. Since the linear change is intuitively easy to understand and the subject can easily grasp the remaining time, it can be applied to many subjects. In addition, although the example of a display of the stepwise display part 211 was shown in FIG. 6, the change of the display of the numerical value display part 212 may be changed linearly. That is, until the breath holding time reaches the predetermined remaining time, nothing is displayed on the numerical value display unit 212, and from the time when the predetermined time is reached, the remaining time is displayed on the numerical value display unit 212, and the remaining time is displayed. The change may be changed linearly.

  FIG. 7 shows a first example in which the display indicating the remaining time until the end of breath holding changes nonlinearly after a predetermined remaining time elapses. Until the breath holding time reaches a predetermined time, the display on the stepped display unit 211 is the same as in FIG. 6, but after the remaining time reaches the predetermined time, the turn-off speed of the stepped display unit 211 is increased. The step display unit 211 is changed nonlinearly. When the turn-off speed increases, a psychological relief that “just a short time is needed to hold the breath” can be obtained even when the breathing state becomes slightly suffocated, and the breath holding can be continued until the end of the photographing time. Such a display method is suitable for elderly people who are not good at breath holding. In this display example, the display change of the numerical value display unit 212 may be changed nonlinearly. By gradually increasing the countdown speed, a psychological relief can be given to the subject.

  FIG. 8 shows a second example in which the display indicating the remaining time until the end of breath holding changes nonlinearly after a predetermined remaining time elapses. Until the breath holding time reaches a predetermined time, the display of the stepped display unit 211 is the same as in FIGS. 6 and 7, but after the remaining time reaches the predetermined time, the turn-off speed of the stepped display unit 211 is set. Slowly, the stepped display unit 211 is changed nonlinearly.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to these, It cannot be overemphasized that various combinations or deformation | transformation within the range of the description are possible.

1 is an overall configuration diagram of an X-ray CT apparatus to which the present invention is applied. It is explanatory drawing when a scan gantry part is seen from the side. It is a figure explaining an instruction | indication display apparatus. It is a figure which shows the flow of operation | movement. It is a figure which shows the example of a display of the instruction | indication of a breath holding. FIG. 6 is a diagram illustrating a first display example of remaining photographing time. It is a figure which shows the 2nd example of a display of imaging | photography remaining time. It is a figure which shows the 3rd example of a display of imaging | photography remaining time.

Explanation of symbols

  1 X-ray CT system, 100 scan gantry unit, 101 X-ray tube, 102 rotating disk, 103 collimator, 104 opening, 105 bed, 106 X-ray detector, 107 data collection device, 108 gantry control device, 109 bed control device , 110 X-ray control device, 120 console, 121 input device, 122 image calculation device, 123 storage device, 124 system control device, 201 (201a-201c) instruction display device, 202 subject, 211 stepwise display unit, 212 Numerical display

Claims (3)

A medical image photographing apparatus provided with an instruction display device that performs a display for instructing a breathing or breath holding operation of a subject,
A measuring device for measuring the elapsed time from the start of shooting;
A determination device for determining whether or not a remaining breath holding time has reached a predetermined time based on a measurement result of the measurement device;
A control device for controlling the instruction display device based on a determination result of the determination device;
A medical image photographing apparatus comprising: The medical image photographing device according to claim 1,
The instruction display device displays a graphic that changes with time,
The medical image photographing apparatus characterized in that the control device linearly decreases the remaining breath holding time and displays it on the instruction display device. The medical image photographing device according to claim 1,
The instruction display device displays a graphic that changes with time,
The control device causes the instruction display device to display the medical image photographing device at a speed that decreases as the remaining breath-holding time decreases.

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