JPH09238934A - Image display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten image reading time by a method wherein a plurality of tomographic images are arithmetically averaged by an arithmetically averaging means and a tomographic image after the arithmetically averaging is shown on a display means to reduce the number of the tomographic images without decreasing the amount of three-dimensional volume information. SOLUTION: An arithmetically averaging device 13 performs an arithmetically averaging processing of a plurality of tomographic images of a subject to generate a tomographic image arithmetically averaged and outputs the plurality of tomographic images arithmetically averaged with a * mark following the inspection date of a header part, a maximum slice number of the tomographic image after the arithmetically averaging and the number of images added. A slice number converter 14 inputs a display mode, the slice number of the tomographic images before the arithmetically averaging as currently displayed or the slice number of the tomographic image after the arithmetically averaging as currently displayed and the number of images added and calculates the slice number of the tomographic images before the arithmetically averaging to be displayed or the slice number of the tomographic image after the arithmetically averaging to be displayed to output the resultant slice number.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an image display system for displaying a tomographic image.

[0002]

2. Description of the Related Art At present, the number of deaths from lung cancer is increasing year by year, and lung cancer mass screenings are being conducted with an emphasis on early detection. In recent years, a helical CT apparatus has begun to be introduced in lung cancer mass screening, and it is possible to image a lung at high speed.

Further, in recent years, studies on three-dimensional helical scanning have been made, and it is expected that the whole lung can be imaged in a short time with a thin slice. Three-dimensional helical scan is already known, for example, Hiroyuki Kudo, et al .: Three-dimensional helical CT using cone beam projection. IEICE Transactions
VoL.J74-D-II No. 8: pp1108-1114 August 1991.

In this paper, a configuration of a CT apparatus and an image reconstruction method for producing a high-resolution three-dimensional CT image at high speed are proposed. In this method, a two-dimensional detector in which an X-ray source that emits a conical X-ray beam and a fan beam detector array are stacked in the body axis direction is continuously rotated, and the bed on which the subject is placed is synchronized within the field of view. And move it. In this paper, an approximate image reconstruction method based on the superposition integration method for fan-beam projection was derived, and a parameter setting method of the X-ray geometry system necessary for actually configuring the apparatus was shown.

There has been an image display system for displaying a tomographic image one by one in order to read a plurality of tomographic images taken by such a three-dimensional helical scan CT apparatus. Hereinafter, an example of the image display system will be described.

Each device in the image display system shown in FIG. 15 will be described. The console 81 is composed of a keyboard and a mouse, and inputs or selects an examination number, a slice number and the like. The control unit 82 includes a central processing unit (CPU) and controls the system. The image storage unit 83 stores a plurality of tomographic images.

As shown in FIG. 16, the tomographic image is composed of a header section 91 and an image data section 92.
Information such as an inspection number, a slice number starting with "1", and a slice thickness is written in the. The display device 84 displays a tomographic image. Further, the display device 84 displays a window including the patient name, the examination number, the number of tomographic images, and the examination date. The image additional information storage unit 85 stores the inspection number of the selected tomographic image, the slice number of the currently displayed tomographic image, and the number of images of the inspection including the selected tomographic image. Below, the number of images of the inspection including the selected tomographic image,
This is called the number of images of the selected inspection.

The slice number increasing / decreasing device 86 inputs the slice number of the currently displayed tomographic image and the number of images of the selected examination, and increases / decreases the slice number to output the increased / decreased slice number. In this case, as shown in FIG. 17, when the doctor presses the prev key 96,
The slice number obtained by reducing the slice number of the currently displayed tomographic image by one is output. When the slice number becomes smaller than 1, the number of images of the selected examination (maximum slice number) is output. Similarly, next key 95
When is pressed, the slice number obtained by incrementing the slice number of the currently displayed tomographic image by 1 is output. When the slice number is larger than the number of images of the selected examination, 1 is output.

The image transfer device 87 inputs the inspection number of the selected tomographic image and the slice number of the currently displayed tomographic image, and the header portion 9 of the tomographic image existing in the image storage unit 83.
1 is read and a tomographic image corresponding to the examination number and the slice number is transferred to the display device 84. The header information reading device 88 reads the header section 91 of the tomographic image existing in the image storage section 83, obtains the number of images of the selected examination, and displays the patient name, the examination number, the number of tomographic images, and the examination date. 8
Transfer to 4. The number of images of the selected examination is the maximum value of the slice number of the selected tomographic image. When the examination number is further selected, the number of images of the selected examination and the slice number “1” are output to the image accompanying information storage unit 85.

Next, the operation of the image display system thus constructed will be described. Here, a case will be described in which an image for one examination is read. Further, it is assumed that tomographic images for a plurality of examinations are already stored in the image storage unit 83.

(A) When the doctor clicks the button of the mouse 94 on the console 81, the header information reading device 88
Reads the header portion 91 of the tomographic image existing in the image storage unit 83, and transfers the patient name, the examination number, the number of tomographic image images, and the examination date to the display device 84. Then, as shown in FIG.
The window 97 is displayed on the display device 84. If the doctor points the tip of the arrow shown in the window 97 to the patient name, for example,
When the button of the mouse 94 is clicked according to Taro Yamada, the inspection number “1093” of the selected tomographic image, the number of images “304” of the selected inspection, and the slice number “1” are output to the image additional information storage unit 85. To be done.

The image transfer device 87 reads the inspection number “1093” and slice number “1” of the selected tomographic image from the image supplementary information storage unit 85, and reads the inspection number “1093” and slice number from the image storage unit 83. The tomographic image of “1” is transferred to the display device 84. The display device 84 displays the tomographic image.

(B) Next, the doctor nexts to the console 81.
When the key 95 is pressed, the slice number increasing / decreasing device 86 causes the slice number “1” of the tomographic image currently displayed from the image supplementary information storage unit 85 and the number “30” of images of the selected examination.
Read "4", increment slice number by "2"
To Since the slice number “2” is smaller than the number “304” of images of the selected examination, the slice number “2” is set.
Is output to the pixel incidental information storage unit 85.

The image transfer device 87 reads the inspection number “1093” of the tomographic image and the slice number “2” of the tomographic image to be displayed, which are selected from the image-accompanying information storage unit 85, and the inspection number is read from the image storage unit 83. The tomographic image of “1093” and the slice number “2” is transferred to the display device 84. The display device 84 displays the tomographic image.

(C) Next, the process of (B) is repeated to display tomographic images with slice numbers 3 to 304. Here, when the doctor presses the next key 95 of the console 81 after the tomographic image of slice number “304” is displayed, the tomographic image of slice number “1” is displayed.

Next, the doctor operates the prev key 9 on the console 81.
The case where 6 is pressed will be described. For example, after the tomographic image of slice number “304” is displayed, the doctor
When the v key 96 is pressed, the slice number increasing / decreasing device 86 reads the slice number “304” of the currently displayed tomographic image and the image number “304” of the selected examination from the image supplementary information storage unit 85, and the slice number Is decreased by 1 to "303". Since the slice number “303” is larger than 1, the slice number “303” is output to the image accompanying information storage unit 85.

The image transfer device 87 reads the inspection number “1093” of the tomographic image and the slice number “303” of the tomographic image to be displayed, which are selected from the image-accompanying information storage section 85,
The tomographic images with the examination number “1093” and the slice number “303” are transferred from the image storage unit 83 to the display device 84. The display device 84 displays the tomographic image. Here, when the doctor presses the prev key 96 of the console 81 after the tomographic image of slice number “1” is displayed, the tomographic image of slice number “304” is displayed.

[0018]

However, the conventional image display system has the following problems. Lung size (from lung apex to lung floor) about 30 cm
In such a case, the number of images per examination is about 300 under the imaging condition where the slice thickness is 1 mm and the slice pitch is 1 mm. For this reason, a lot of time was required for image interpretation.

In order to shorten the image reading time, it is necessary to reduce the number of images to the extent that it does not hinder the detection of abnormalities in tomographic images. However, simply reducing the number of images by thinning out reduces the amount of three-dimensional volume information and is not appropriate. In addition, if an abnormality is found by reading the tomographic images after reducing the number of images, it is necessary to read the tomographic images before reducing the number of images at the original high resolution, so that the original tomographic images can also be read. You also need to do it.

Therefore, a first object of the present invention is to provide an image display system capable of reducing the number of tomographic images and shortening the image reading time without reducing the amount of three-dimensional volume information. A second object of the present invention is to provide an image display system capable of interpreting both tomographic images before and after averaging.

[0021]

In order to solve the above problems, the present invention adopts the following means. The invention of claim 1 is
An addition and averaging unit that performs addition and averaging processing on a plurality of tomographic images to create an addition and averaged tomographic image, and a display unit that displays the tomographic image after the addition and averaging created by the addition and averaging unit.

According to the present invention, since the averaging means averages a plurality of tomographic images and the tomographic image after the averaging is displayed on the display means, the number of images can be reduced and the image reading time can be shortened. Further, since the image information of the plurality of tomographic images before the averaging is reflected in the tomographic image after the averaging, the amount of the three-dimensional volume information is not reduced.

According to a second aspect of the present invention, storage means for storing a plurality of tomographic images before arithmetic averaging, and arithmetic averaging processing performed on the plurality of tomographic images stored in the storage means to obtain an arithmetic average. And a display mode switching means for performing a display mode switching between a display mode for displaying the plurality of tomographic images before arithmetic averaging and a display mode for displaying the tomographic images after arithmetic averaging; Reading means for reading out a plurality of tomographic images before arithmetic averaging stored in the storage means based on the display mode switched by the mode switching means or a tomographic image after arithmetic averaging created by the arithmetic averaging means; and the reading means. Display means for displaying a plurality of tomographic images before arithmetic averaging or a tomographic image after arithmetic averaging.

According to the present invention, the averaging means performs the averaging process on the plurality of tomographic images stored in the storage means to create the tomographic image subjected to the averaging, and the display mode switching means switches the display mode. The reading means reads a plurality of tomographic images before arithmetic mean stored in the storage means based on the display mode or a tomographic image after arithmetic mean created by the arithmetic mean means, and the display means reads a plurality of tomographic images before arithmetic mean The tomographic image of or the tomographic image after the averaging is displayed. As a result, a tomographic image can be selectively displayed according to the purpose by switching the display mode.

According to a third aspect of the present invention, the averaging means is
Raw data arithmetic averaging means for performing arithmetic averaging processing on raw data to create a plurality of tomographic images to generate arithmetic averaged raw data, and raw data arithmetic averaged by the raw data arithmetic averaging means Reconstructing means for performing a structuring process to create the tomographic image after the averaging.

According to the present invention, raw data for creating a plurality of tomographic images is subjected to arithmetic averaging to generate arithmetic mean raw data, and the arithmetic mean raw data is reconstructed and added. By creating an averaged tomographic image and displaying the averaged tomographic image, the number of images can be reduced and the reading time can be shortened. Further, since the information of the raw data before the averaging is reflected in the tomographic image after the averaging, the amount of the three-dimensional volume information is not reduced.

In the invention of claim 4, the averaging means performs an averaging process on a plurality of tomographic images before the averaging by a predetermined number of added sheets.

According to a fifth aspect of the present invention, the number of tomographic images is converted between the number of tomographic images before arithmetic averaging and the number of tomographic images after arithmetic averaging based on the previously designated number of added images. Equipped with conversion means.

According to the present invention, the number of tomographic images can be converted between the number of tomographic images before arithmetic averaging and the number of tomographic images after arithmetic averaging.

Further, the number storage means for storing the tomographic image before the averaging in association with the number of the tomographic image and the number storage means for storing the tomographic image after the averaging in association with the number of the tomographic image An input means for inputting one of the number of tomographic images before averaging and the number of tomographic images after averaging is provided, and the number converting means is the number of tomographic images input by the input means. Converting the number, the reading means
A tomographic image corresponding to the number of tomographic images converted by the number conversion unit may be output from the number storage unit to the display unit.

According to this, the input means inputs the number of tomographic images before the averaging or the number of tomographic images after the averaging, and the number converting means converts the number of the input tomographic images. A tomographic image corresponding to the converted number of tomographic images can be displayed on the display means.

Further, the image forming apparatus further comprises a sheet number increasing / decreasing means for increasing / decreasing the sheet number of the tomographic image converted by the sheet number converting means, and the reading means corresponds to the sheet number of the tomographic image increased / decreased by the sheet number increasing / decreasing means. A tomographic image may be output from the number storage means to the display means.

According to this, when the sheet number increasing / decreasing means increases / decreases the sheet number, the tomographic image corresponding to the increased / decreased sheet number can be displayed on the display means.

Further, the reading means causes the display means to display a tomographic image before arithmetic averaging having the smallest number of tomographic images among a plurality of tomographic images before arithmetic averaging corresponding to the tomographic image after arithmetic averaging. You can output it.

Further, the tomographic image after the arithmetic mean displayed on the display means by switching the display mode may be a tomographic image after the arithmetic mean corresponding to the tomographic image before the arithmetic mean. The arithmetic mean may perform arithmetic mean processing on raw data corresponding to the tomographic image after arithmetic mean.

Further, the tomographic image before the averaging is stored in correspondence with the number of the tomographic image and the examination number of the subject, and the tomographic image after the averaging is stored in correspondence with the number of the tomographic image. And a means for inputting the examination number of the subject, wherein the means for converting the number of images of the tomographic image before arithmetic mean corresponding to the examination number of the subject inputted from the input means. The sheet number is converted into the sheet number of the tomographic image after the averaging, and the reading means stores the tomographic image after the averaging corresponding to the sheet number of the tomographic image converted by the sheet number converting means. May be output to the display means.

According to this, the input means inputs the examination number of the subject, and the sheet number conversion means calculates the sheet number of the tomographic image before the averaging corresponding to the inputted examination number of the subject after the averaging. When converted into the number of tomographic images, the tomographic image after the averaging corresponding to the converted number of tomographic images can be displayed on the display means.

Further, the averaging means is an X-ray source which bombards the subject with X-rays at predetermined angles while rotating.
A group of X-ray detectors arranged in an arc shape or an annular shape to detect X-rays that have passed through the subject from the X-ray source, and the X-ray source rotates a plurality of times, and the X-ray source sandwiches the subject. And X
When the subject moves at a predetermined speed in a direction substantially orthogonal to the plane formed by the X-ray detector group facing the radiation source, multi-directions based on the transmitted X-rays detected by the X-ray detector group Collecting means for collecting helical scan data by collecting projection data from the reconstructing means, reconstructing means for forming the plurality of tomographic images by reconstructing the helical scan data obtained by the collecting means, and reconstructing means X including a tomographic image averaging means for creating an averaging tomographic image by performing an averaging process on the plurality of tomographic images obtained in
It may be a line CT device.

According to this, in the X-ray CT apparatus, the reconstruction means reconstructs the helical scan data obtained by the collection means to create the plurality of tomographic images, and the tomographic image averaging means is obtained. It is also possible to create an averaging tomographic image by performing averaging processing on the plurality of tomographic images. Then, the averaged tomographic image may be displayed on the display means.

Further, the averaging means is an X-ray CT provided with the raw data averaging means and the reconstructing means.
The raw data addition and averaging means may be an X-ray source for irradiating the subject with X-rays at predetermined angles while rotating, and the X-ray source arranged in an arc shape or an annular shape. X-ray detector group that detects X-rays that have passed through the subject and the X-ray source rotates a plurality of times, and the X-ray detection facing the X-ray source and the X-ray source with the subject interposed therebetween. By collecting projection data from multiple directions based on the transmitted X-rays detected by the X-ray detector group when the subject moves at a predetermined speed in a direction substantially orthogonal to the plane formed by the X-ray detector group. Collecting means for obtaining helical scan data corresponding to the plurality of tomographic images as raw data before averaging, and raw data after averaging by performing averaging processing on the raw data before averaging obtained by the collecting means. Equipped with means for collecting and averaging collected data It may be.

According to this, in the X-ray CT apparatus, the collecting means obtains helical scan data corresponding to a plurality of tomographic images as raw data before average addition, and the collected data addition / averaging means obtains before average addition. Raw data after arithmetic mean is created by performing arithmetic mean processing on the raw data, and reconstructing means performs reconstruction processing on raw data after arithmetic mean to create a tomographic image after the arithmetic mean. You can also Then, the averaged tomographic image may be displayed on the display means.

[0042]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an image display system of the present invention will be described in detail below with reference to the drawings.

[First Embodiment] FIG. 1 shows the configuration of an image display system of the present invention. In the image display system shown in FIG. 1, the bus 11 includes a control unit 12, an averaging device 13,
Slice number conversion device 14, image storage unit 15, console 1
6, an image additional information storage unit 17, a display device 18, a slice number increasing / decreasing device 19, a display mode switching device 20, an image transfer device 21, and a header information reading device 22 are connected.

The control unit 12 is composed of a CPU or the like and controls the system. The averaging device 13 creates an averaging tomographic image by performing averaging processing on a plurality of tomographic images of the subject. The arithmetic averaging device 13 displays the slice thickness before the selected arithmetic average, the selected plurality of tomographic images before the arithmetic average, the number of images of the selected examination, and the slice thickness of the tomographic image after the arithmetic average from the console 16. When input, a plurality of tomographic images subjected to arithmetic averaging with * marks after the inspection date of the header portion 91a shown in FIG. 2, the maximum slice number of the tomographic image after arithmetic averaging, and the number of added images are output.

The * mark is data identification information for identifying a tomographic image after arithmetic averaging and a tomographic image before arithmetic averaging. In this example, in the tomographic image after the averaging shown in FIG. 2, the * mark is added after the inspection date of the header portion 91a, and in the tomographic image before the averaging shown in FIG. The * mark is not added after the inspection date. The data identification information of the tomographic image before the averaging may be set to "1" and the data identification information of the tomographic image after the averaging may be set to "0".

When obtaining the number of sheets to be added, it is necessary to consider three cases as shown in FIG. FIG. 3 (a)
Is the case where the slice thickness is smaller than the slice pitch. When the number of added sheets is n, the slice pitch is p, the slice thickness is t, and the width from the beginning to the end of the plurality of tomographic images is l, l = nt + (n-1) (pt), the above equation holds. , The added number “n” is n = (l−t + p) / p (a).

FIG. 3B shows the case where the slice thickness is larger than the slice pitch.

L = nt- (n-1) (t-p) Since the above equation is established, the number "n" of additions is n = (l-t + p) / p (b). The number of sheets added at this time is the same as the number of sheets added in the equation (1).

FIG. 3C shows a case where the slice pitch and the slice thickness are equal. The added number “n” is n =
1 / t (c). In the equation (c), p is t in the equations (a) and (b).
It is when replaced by. So in all cases,
It can be represented by the formula (a).

When obtaining volume data of the whole lung,
Since it is usual to set t = p as shown in FIG. 3C,
Here, the number of sheets to be added is calculated as follows from the selected slice thickness before the averaging and the slice thickness of the tomographic image after the averaging.

The slice thickness before the selected averaging is xm
In the case of m, when the slice thickness of the tomographic image after the addition and averaging is ymm, the number of additions is a positive integer rounded to the first decimal place of y / x from the equation (c). However, the number of images to be averaged at the bottom of the lung is below the decimal point of y / x.
If the number is less than the positive integer rounded off, only the number is added and averaged. Here, it is assumed that the slice number of the tomographic image before averaging is smaller at the lung apex and the slice number is larger at the lung bottom.

For example, as shown in FIG. 4, assuming that the selected slice thickness before the averaging is 1 mm and the slice thickness of the tomographic image after the averaging is 10 mm, the number of added sheets is 10. However, as shown in FIG. 4, when the number of slices of the plurality of tomographic images IM1 to IM304 before averaging is 304, the number of addition is 10 at the lung apex 32. However, the number of images to be averaged remains at the bottom of the lung 33 by four. In this case, the number of added sheets is four.

As shown in FIG. 5, the averaging device 13 is set to 1
When averaging 0 tomographic images IM1 to IM10, ten pixels X111 to X1011 whose positions correspond to each other are used.
The average value of the pixel values of the
3 (in the image storage unit 15 shown in FIG. 1) corresponding pixel AV
Write 11 The image thus obtained is taken as a tomographic image after the averaging.

Further, the slice number of the tomographic image after the averaging is obtained. Letting a be the number of sheets to be added, and let the maximum slice number be b among the tomographic images before the averaging used when creating the tomographic image after the averaging, the slice number c of the tomographic image after the average is b / It is a positive integer rounded up to the nearest whole number.

For example, 304 tomographic images IM shown in FIG.
From 1 to IM 304, the slice number of the tomographic image after the addition averaging is calculated with 10 additions. The slice number of the tomographic image AVIM1 after the arithmetic average created from the tomographic images IM1 to IM10 before the arithmetic average of the slice numbers 1 to 10 is “1”. The slice number of the tomographic image AVIM2 after the arithmetic average created from the tomographic images IM11 to IM20 before the arithmetic average of the slice numbers 11 to 20 is “2”. Similarly, the slice number of the tomographic image after the averaging is obtained.

The slice number conversion device 14 displays the display mode (0 or 1), the slice number of the tomographic image before the averaging currently displayed or the slice number of the tomographic image after the averaging currently displayed, and the number of added images. Is input, the slice number of the tomographic image before arithmetic mean to be displayed or the slice number of the tomographic image after arithmetic mean to be displayed is calculated, and the slice number is output.

Here, the slice number conversion device 14
When the display mode is "0", the slice number of the tomographic image after the averaging to be displayed is output. The slice number to be output is a positive integer value obtained by rounding up the value after dividing the slice number of the currently displayed tomographic image before arithmetic averaging by the number of sheets to be added up. For example, if the slice number of the tomographic image before the averaging which is currently displayed is 41 and the number of added images is 10, the slice number corresponding to the tomographic image after the averaging to be displayed is 5.

In the case of the display mode "1", the slice number conversion device 14 outputs the slice number of the tomographic image before the averaging to be displayed. The slice number to be output is a positive integer obtained by multiplying the value obtained by subtracting 1 from the slice number of the currently displayed tomographic image after addition and averaging, and adding 1 to the value. For example, if the slice number of the currently displayed tomographic image after the averaging is 2 and the number of added images is 10, the slice number corresponding to the tomographic image before the averaging to be displayed is 11.

The image storage unit 15 stores a plurality of tomographic images before arithmetic averaging and a plurality of tomographic images after arithmetic averaging. Operation console 1
Reference numeral 6 is composed of a keyboard and a mouse, and inputs the slice thickness of the tomographic image before the averaging, the slice thickness of the tomographic image after the averaging, the examination number, the slice number, the display mode, the number of images of the selected examination, or the like. select.

The operation console 16 switches the display mode for displaying the tomographic image before arithmetic averaging and the display mode for displaying the tomographic image after arithmetic averaging, and the slice thickness of the tomographic image after arithmetic averaging. The added average slice thickness key 37 to be set and the end key 38 to end the tomographic image display processing
Is provided.

The image additional information storage unit 17 stores the selected slice thickness before the averaging, the slice thickness of the tomographic image after the averaging, the number of images of the selected examination, and the maximum slice number of the tomographic image after the averaging. The number of additions, the inspection number of the selected tomographic image, the display mode, the slice number of the tomographic image currently displayed, etc. are stored.

The display device 18 displays the transferred tomographic image. As shown in FIG. 18, the display device 18 displays a window including a patient name, an examination number, the number of tomographic images, and an examination date.

The slice number increasing / decreasing device 19 displays the display mode, the slice number of the tomographic image before arithmetic averaging or the tomographic image after arithmetic averaging, the maximum slice number of the tomographic image after arithmetic averaging, or the selected slice number. When the number of images for the examination is input, the slice number is increased or decreased and the increased or decreased slice number is output.

When the display mode is "0" and the prev key 96 is pressed by the doctor as shown in FIG. 7,
The slice number decremented by 1 is output. When the prev key 96 is pressed and the slice number becomes smaller than 1, the maximum slice number of the tomographic image after the averaging is output. When the next key 95 is pressed, the slice number incremented by 1 is output. When the next key 95 is pressed and the slice number becomes larger than the maximum slice number of the tomographic image after the averaging, the slice number “1” is output.

When the doctor presses the perv key 96 when the display mode is "1", the slice number decremented by 1 is output. When the prev key 96 is pressed and the slice number becomes smaller than 1, the slice number which is the number of images of the selected examination is output. next
When the key 96 is pressed, the slice number incremented by 1 is output. When the next key 96 is pressed and the slice number becomes larger than the number of images of the selected examination, the slice number “1” is output.

When the display mode is input from the display mode switching key 35, the display mode switching device 20 switches the display mode and outputs the switched display mode. When the display mode switching key 35 shown in FIG. 7 is pressed by the doctor and the current display mode is "0", the display mode "1" is output. When the current display mode is "1", the display mode "0" is output.

The image transfer device 21 receives the display mode, the inspection number of the selected tomographic image, the slice number of the tomographic image before the averaging to be displayed, or the slice number of the tomographic image after the averaging to be displayed. Then, the header portion of the tomographic image existing in the image storage unit 15 is read, and the tomographic image corresponding to the examination number and the slice number is transferred to the display device 18.

The image transfer device 21 has a display mode of "0".
Then, the tomographic image corresponding to the examination number and the slice number and having the * mark added thereto after the averaging is transferred to the display device 18. When the display mode is “1”, the image transfer device 21 transfers to the display device 18 a tomographic image corresponding to the inspection number and the slice number and not added with * mark before addition averaging.

The header information reading device 22 reads the header portion of the tomographic image existing in the image storage unit 15, obtains the number of images of the selected examination, and obtains the patient name, examination number, number of tomographic images, and examination date. Transfer to the display device 18. Further, the header information reading device 22 outputs the number of images of the selected examination and the selected slice thickness before averaging to the image accompanying information storage unit 17. Here, the number of images of the selected examination is the maximum slice number.

Next, the operation of the image display system thus configured will be described with reference to the flow charts shown in FIGS. FIG. 8 is a flowchart showing the display process of the tomographic image after the averaging when the display mode is 0.
FIG. 9 is a flowchart showing a display process of a tomographic image before arithmetic averaging when the display mode is 1.

Here, a case will be described in which a tomographic image (slice thickness 1 mm) before the averaging for one examination is read with a slice thickness of 10 mm of the tomographic image after the averaging.

Further, the tomographic images before the averaging of a plurality of examinations are stored in the image storage unit 15, the display mode is "0", and the slice thickness of the tomographic image after the averaging is "10 mm".
Will be described as already stored in the image accompanying information storage unit 17.

(1) First, the examination number, the number of images of the selected examination, and the slice thickness of the tomographic image after the averaging are obtained as follows (step S11). When the doctor clicks the button of the mouse 94 on the console 16, the header information reading device 22 reads the header portion of the tomographic image existing in the image storage unit 15, and displays the patient name, examination number, number of tomographic images, and examination date. Transfer to the display device 18.

Further, the window 97 shown in FIG. 16 is displayed on the display device 18. As shown in FIG. 16, the tip of the arrow is aligned with the patient name, for example, Taro Yamada, and the mouse 94
When the button of is clicked, the inspection number of the selected tomographic image is “1093” and the number of images of the selected inspection is “304”.
Slice ", slice thickness before selected averaging" 1 mm ",
The slice number “1” is output to the image accompanying information storage unit 15.

(2) Next, the number of added images, the tomographic image after the averaging, and the maximum slice number of the tomographic image after the averaging are obtained as follows (step S13). The averaging device 13
Slice thickness before arithmetic mean “1 mm” selected from the image accompanying information storage unit 17, slice thickness of tomographic image after arithmetic mean “10 mm”, number of images of selected examination “304”
"304 sheets" for one inspection from the image storage unit 15
The tomographic image before the averaging of is read and the number of additions is obtained.

The selected slice thickness before averaging is 1 m
m, since the slice thickness of the tomographic image after the averaging is 10 mm, the number of addition is 10. The added number "10"
The “sheet” is output to the image accompanying information storage unit 17.

Next, the averaging device 13 creates 304 tomographic images after the averaging from 304 tomographic images IM1 to IM304 before the averaging, as shown in FIG. To do. Since the number of added images is 10, as shown in FIG. 6, tomographic images AVIM1 to 31 after addition and averaging of 31 images are added.
The AVIM 31 is created. In the tomographic image after the averaging,
The same slice number and * mark are added to the slice numbers shown in FIG. 6, respectively. The averaging device 13
The tomographic image after the arithmetic mean is output to the image storage unit 15, and the maximum slice number “3” of the tomographic image after the arithmetic mean is further output.
1 ″ is output to the image accompanying information storage unit 17.

(3) The image transfer device 21 inputs the display mode “0”, the slice number “1”, and the examination number “1093” of the selected tomographic image from the image supplementary information storage unit 17, and the image storage unit 15 Read the header part of the tomographic image existing in, and correspond to the inspection number and the slice number, and *
The display device 18 displays the tomographic image after addition and averaging with the mark added.
(Step 15). The display device 18 displays the transferred tomographic image.

(4) Next, when the end key 38 is not pressed (step S16) and the doctor presses the next key 95 in the console 16 (step S17), the slice number increasing / decreasing device 19 stores the image additional information storage. The display mode “0” is read from the section 17. The slice number increasing / decreasing device 19 determines whether the display mode is "0" (step S1).
9). Here, since the display mode is “0”, the slice number increasing / decreasing device 19 causes the slice number increasing / decreasing device 19 to display the slice number “1” of the tomographic image after the averaging currently displayed from the image-accompanying information storage unit 17 and the slice after the averaging. Maximum slice number of the image "3
"1" is read, the slice number is incremented by 1 and "2"
(Step S21). Since the slice number “2” is smaller than the maximum slice number “31” (upper limit value) of the tomographic image after the averaging (step S23), the slice number “2” is output to the image additional information storage unit 17.

(5) Next, the image transfer device 21 inputs the display mode “0”, the slice number “2”, and the examination number “1093” of the selected tomographic image from the image additional information storage unit 17, The header portion of the tomographic image existing in the storage unit 15 is read, and the tomographic image corresponding to the examination number and the slice number and having the * mark added thereto after the averaging is transferred to the display device 18. The display device 18 displays the transferred tomographic image (step S25).

(6) Similar to (4) and (5), the display device 1 displays the tomographic images after the averaging of slice numbers 3 to 31.
8 is displayed (step S17 to step S25). Here, when the doctor presses the next key 95 of the operation console 16 after displaying the tomographic image after the averaging of the slice number “31”, the slice number increasing / decreasing device 19 causes the image additional information storage unit 17 to read The display mode "0" is read.

Here, since the display mode is "0", the slice number increasing / decreasing device 19 causes the slice number "31" of the tomographic image after addition averaging currently displayed from the image supplementary information storage unit "31", addition averaging. The maximum slice number "31" of the subsequent tomographic image is input, and the slice number is incremented by 1 to "32". Since the slice number “32” is larger than the maximum slice number “31” of the tomographic image after the averaging,
The slice number “1” (lower limit value) is assigned to the image supplementary information storage unit 1
7 (step S27). Similar to the above (5), the tomographic image of slice number "1" is displayed (step S15).

Next, the doctor selects the prev key 9 on the console 16.
The case where 6 is pressed will be described. Here, pr is displayed after the tomographic image of the slice number “31” after the averaging is displayed.
It is assumed that the ev key 96 is pressed (step S29). The slice number increasing / decreasing device 19 reads the display mode “0” from the image accompanying information storage unit 17. The slice number increasing / decreasing device 19 determines whether the display mode is "0" (step S30).

Here, since the display mode is "0", the slice number increasing / decreasing device 19 causes the slice number "31" of the tomographic image after addition averaging currently displayed from the image additional information storage unit "31", addition averaging. The maximum slice number "31" of the subsequent tomographic image is read, and the slice number is decremented by 1 to "30" (step S31). Since the slice number “30” is larger than 1 (step S33), the slice number “30” is output to the image additional information storage unit 17. Similar to (5) above, the tomographic image is displayed (step S35).

Here, after displaying the tomographic image of the slice number “1” after the averaging, the doctor prev of the operation console 16.
When the key 96 is pressed, the slice number increasing / decreasing device 19
Reads the display mode “0” from the image accompanying information storage unit 17. Here, since the display mode is “0”, the slice number increasing / decreasing device 19 causes the slice number increasing / decreasing device 19 to display the slice number “1” of the tomographic image after the averaging currently displayed from the image-accompanying information storage unit 17 and the slice after the averaging. The maximum slice number "31" of the image is read and the slice number is decremented by 1 to "0".

Since the slice number "0" is smaller than 1,
The slice number “0” is changed to the maximum slice number “31” of the tomographic image after the averaging, and the changed slice number is output to the image additional information storage unit 17 (step S3).
7). The tomographic image is displayed in the same manner as (5) above.

Next, the case where the doctor presses the display mode switching key 35 in the console 16 will be described. here,
For example, when the display mode switching key 35 is pressed after displaying the tomographic image of the slice number “29” after averaging (step S19 or step S30), the display mode switching device 20 stores the image supplementary information storage. The display mode "0" is read from the section 17 and the display mode "1" is switched.
Is output to the image accompanying information storage unit 17.

The slice number conversion device 14 reads the display mode “1” from the image supplementary information storage unit 17. Here, since the display mode is "1", the slice number conversion device 14 has the slice number "29" of the tomographic image after addition averaging currently displayed from the image supplementary information storage unit 17 and the number of additions "10". Is read and the slice number “281” of the tomographic image before arithmetic averaging to be displayed corresponding to the tomographic image after arithmetic averaging is output to the image accompanying information storage unit 17 (step S39).

Next, the image transfer device 21 displays the display mode “1” from the image supplementary information storage unit 17, the slice number “281” of the tomographic image before arithmetic mean to be displayed, and the examination number “of the selected tomographic image”. 1093 "is read. Image transfer device 2
1 reads the header portion of the tomographic image existing in the image storage unit 15, corresponds to the examination number and the slice number, and
The tomographic image before the averaging without the * mark is transferred to the display device 18. Further, the display device 18 displays the transferred tomographic image (step S41).

Next, the doctor pushes the next key 9 on the console 16.
The case of pressing 5 will be described. Here, in step S42, if the end key 38 is not pressed and, for example, the next key 95 is pressed after displaying the tomographic image of the slice number "281" (step S43), the slice number increasing / decreasing device 19 causes the image attachment The display mode "1" is read from the information storage unit 17. Here, since the display mode is "1" (step S44), the slice number increasing / decreasing device 19
Reads the slice number “281” of the tomographic image before arithmetic mean and the number “304” of images of the selected examination currently displayed from the image supplementary information storage unit 17, and increments the slice number by “282”. (Step S45).

Since the slice number "282" is smaller than the number of images "304" of the selected examination (step S4)
7), the slice number “282” is output to the image additional information storage unit 17. The display device 18 displays the tomographic image (step S49). Similarly, the processing from step S43 to step S49 is repeated.

Here, after the tomographic image of slice number “304” is displayed, the doctor presses the next key 9 on the console 16.
When 5 is pressed, the slice number “304” is changed to the slice number “1” and the slice number “1” is output to the image additional information storage unit 17 (step S51). Similarly, the tomographic image is displayed.

Next, the doctor selects the prev key 9 on the console 16.
The case where 6 is pressed will be described. Here, for example,
After displaying the tomographic image of slice number “282”, pre
When the v key 96 is pressed (step S53), the slice number increasing / decreasing device 19 reads the display mode "1" from the image accompanying information storage unit 17. Here, since the display mode is "1" (step S54), the slice number increasing / decreasing device 19 causes the slice number "28" of the tomographic image before addition averaging currently displayed from the image accompanying information storage unit 17 to be displayed.
2 ”, the number“ 304 ”of images of the selected examination is read, and the slice number is decremented by 1 to“ 281 ”(step S55). Since the slice number“ 281 ”is larger than 1 (step S57), the slice is Number "28
1 "is output to the image accompanying information storage unit 17. Similarly, the tomographic image is displayed (step S59).

Here, after the tomographic image of the slice number “1” before the averaging is displayed, the doctor pre-operates the console 16.
When the v key 96 is pressed, the slice number in which the slice number is changed to the image number "304" of the selected examination is output to the image additional information storage unit 17 (step S61).
Similarly, the tomographic image is displayed.

Next, a case where the doctor presses the display mode switching key 35 on the console 16 will be described. Here, when the display mode switching key 35 is pressed after the tomographic image of the slice number “279” before the averaging is displayed (step S44 or step S54), the display mode switching device 20 causes the image supplementary information. The display mode “1” is read from the storage unit 17, and the converted display mode “0” is output to the image accompanying information storage unit 17.

Next, the slice number conversion device 14 reads the display mode “0” from the image additional information storage unit 17.
Here, since the display mode is “0”, the slice number conversion device 14 causes the slice number “2” of the tomographic image before addition averaging, which is currently displayed, to be displayed in the image supplementary information storage unit 17.
79 "and the number of additions" 10 "are read, and the slice number" 28 "of the tomographic image after addition averaging to be displayed corresponding to the tomographic image before addition averaging is output to the image additional information storage unit 17.

(3) The image transfer device 21 displays the display mode "0" from the image supplementary information storage unit 17, the slice number "28" of the tomographic image after the averaging to be displayed, and the inspection number "of the selected tomographic image". 1093 "is read. Image transfer device 21
Reads the header portion of the tomographic image existing in the image storage unit 15, corresponds to the examination number and the slice number, and *
The display device 18 displays the tomographic image after addition and averaging with the mark added.
Transfer to The display device 18 displays the tomographic image (step S15).

In step S29, prev
If the key 96 is not pressed, the process returns to step S16.
When the prev key 96 is not pressed in step S53, the process returns to step S42. Then, when ending the display process of the tomographic image, the end key 38 is pressed in step S16 or step S42.

In the above description, the case of displaying a tomographic image for one examination of one subject has been described. For example, in the case of displaying another new tomographic image of the subject, the examination number of the subject is matched with another examination number in the window 97 shown in FIG. 16 and the button of the mouse 94 is clicked. . The slice number conversion device 14 converts the number of tomographic images before arithmetic averaging corresponding to the input examination number of the subject into the number of tomographic images after arithmetic averaging. Since the image transfer device 21 outputs the tomographic image after the averaging corresponding to the converted number of tomographic images from the image storage unit 15 to the display device 18, another display object is displayed on the display device 18. A tomographic image after averaging is displayed.

In this way, a plurality of tomographic images are arithmetically averaged to create a tomographic image after arithmetic averaging, and the tomographic image after arithmetic averaging is displayed, so that the number of images can be reduced and the image reading time can be shortened. Further, in the conventional method of reducing the number of images by thinning out, the amount of three-dimensional volume information is reduced, but in the first embodiment, the tomographic image after arithmetic averaging is the image of a plurality of tomographic images before arithmetic averaging. Since the information is reflected, the amount of 3D volume information does not decrease.

Further, by having the display mode switching device 20 for switching the display mode of the tomographic image, both the tomographic image before the averaging and the tomographic image after the averaging can be read. For example, usually, when performing image interpretation or displaying a new tomographic image of the subject, the tomographic image after averaging is displayed. Further, when an abnormality is found in the tomographic image, the tomographic image before the averaging is displayed so that the details of the abnormal portion can be grasped. Further, by converting the number of tomographic images, a desired tomographic image after arithmetic averaging or a desired tomographic image before arithmetic averaging can be immediately obtained.

In the first embodiment, the number of sheets to be added is calculated from the selected slice thickness before the averaging and the slice thickness of the tomographic image after the averaging, but the method is not limited to the above method. , For example, the keyboard 93a
You may enter it directly from.

Further, in the first embodiment, when the display mode is changed from the tomographic image after the averaging to the tomographic image before the averaging, the tomographic image after the averaging is used. Of the tomographic images, the tomographic image before the averaging with the smallest slice number was displayed. For example, among the tomographic images before arithmetic averaging used to create the tomographic image after arithmetic averaging, a tomographic image before slice averaging of slice numbers with intermediate slice numbers may be displayed.

Further, in the first embodiment, when the display mode is changed to the mode for displaying the tomographic image after the averaging,
The tomographic image after arithmetic averaging corresponding to the tomographic image before arithmetic averaging that is currently displayed was displayed, but the addition that was already displayed when the display mode was changed to the mode that displays the tomographic image before arithmetic averaging A tomographic image after averaging may be displayed. For example, as shown in FIG. 10, when the display mode is changed to the mode in which the tomographic image before the averaging is displayed after the tomographic image AVIM1 after the averaging of the slice number “1” is displayed, the slice number “ A tomographic image IM1 before the averaging of 1 ″ is displayed (step S1).

Next, press the next key 95 ten times,
It is assumed that the tomographic image IM11 before the averaging of the slice number “11” is displayed (step S3). Next, when the display mode is changed to the mode of displaying the tomographic image after the averaging, in the first embodiment, the tomographic image AVIM2 after the averaging of the slice number “2” is displayed (step S4).
The tomographic image AVIM1 after the averaging of the slice number “1” that has already been displayed when the display mode is changed to the mode in which the tomographic image IM1 before the averaging is displayed may be displayed (step S5).

Further, in the first embodiment, the slice thickness of the tomographic image after the averaging is set to 10 mm, but the slice thickness of the tomographic image after the averaging can be changed. Further, in the first embodiment, the tomographic images are displayed one by one when the mode is changed from the tomographic image after the averaging to the tomographic image before the averaging. However, the currently displayed tomographic image after the averaging is displayed. A plurality of tomographic images before arithmetic mean corresponding to the images may be simultaneously displayed. Furthermore, the first embodiment can be implemented as long as it is a tomographic image, and can be applied to any tomographic image taken by a CT apparatus, an MRI apparatus, or a nuclear medicine apparatus.

[Second Embodiment] Next, a second embodiment of the image display system of the present invention will be described. In the first embodiment, an averaged tomographic image is created from a plurality of tomographic images, but in the second embodiment, the raw data is arithmetically averaged and the arithmetically averaged raw data is reconstructed to be arithmetically averaged. It is characterized by creating a tomographic image. Hereinafter, the details will be described.

FIG. 11 shows the structure of an image display system including an X-ray CT apparatus. In the X-ray CT apparatus 40a, the gantry 41 is provided with an annular hole portion 47, and the bed top plate 43 on which the subject 45 is placed moves at a predetermined speed in the arrow direction, so that a plurality of slices of the subject 45 are cut. An image (slice image) is obtained.

The X-ray CT apparatus 40a further includes an X-ray source 5
1, X-ray detector group 53, data acquisition unit 55, reconstruction unit 5
6, a storage unit 57, and a display unit 58. X-ray source 51
Irradiates the subject 45 with X-rays at predetermined angles while rotating the outer circumference of the annular hole 47. X-ray detector group 5
3 is arranged on the entire outer periphery of the annular hole portion 47
The X-ray transmitted from the radiation source 51 through the subject 45 is detected.

In the data collecting section 55, the X-ray source 51 is rotated a plurality of times and the subject 45 is controlled by the subject 45.
The X-ray source 51 and the X-ray source 51 facing the X-ray source 51 with the X-axis in between
When the X-ray detector group 5 moves at a predetermined speed in a direction (arrow direction) substantially orthogonal to the plane P formed by the line detector group.
The helical scan data corresponding to the plurality of tomographic images (plural slice images) is obtained by collecting projection data from multiple directions based on the transmitted X-rays detected in 3.

For example, as shown in FIG. 12, lung apex 65
To the lung floor 67, raw data D1 to Dn10 for creating a plurality of tomographic images are obtained based on the helical scan data. The raw data D1 to Dn10 may be created by extracting a part of the helical scan data, or may be created by subjecting the helical scan data to an interpolation process.

The reconstruction unit 56 creates a plurality of tomographic images by reconstructing the collected helical scan data and stores them in the storage unit 57. The display unit 58 includes a storage unit 57.
The tomographic image stored in is displayed.

The image display system 10a includes a bus 11, a controller 12, an averaging device 13a, and a slice conversion device 1.
4, an image storage unit 15, a console 16, an image supplementary information storage unit 17, a display device 18, a slice number increasing / decreasing device 19, a display mode switching device 20, an image transfer device 21, and a header information reading device 22.

The arithmetic mean device 13a includes a raw data arithmetic mean unit 61 and a reconstruction unit 63. Raw data addition averaging unit 6
In the first example, raw data obtained by adding and averaging is created by performing an averaging process on the raw data for creating a plurality of tomographic images collected by the data collecting unit 55. Here, the raw data addition / averaging unit 61 performs addition / averaging processing on the raw data before the addition / averaging by the number of additions specified in advance.

The reconstructing unit 63 creates a tomographic image after arithmetic averaging by performing a reconstruction process on the raw data arithmetically averaged by the raw data arithmetic averaging unit 61. Display device 1
Reference numeral 8 displays the tomographic image after the averaging created by the reconstruction unit 63. The image storage unit 15 stores a plurality of tomographic images before arithmetic mean obtained by the reconstruction unit 56 in the X-ray CT apparatus 40a via the bus 11, and the reconstruction unit in the arithmetic mean apparatus 13a. The tomographic image after the averaging obtained in 63 is stored.

Since the other structure of the image display system 10a is the same as that of the first embodiment,
Here, the details are omitted.

In such a configuration, first, a plurality of tomographic images before arithmetic mean obtained by the reconstruction unit 56 in the X-ray CT apparatus 40a are stored in the image storage unit 15 in advance. Next, raw data corresponding to a plurality of tomographic images is input from the data collection unit 55 to the raw data addition / averaging unit 61 via the bus 11. As shown in FIG. 12, the raw data arithmetic mean unit 61 arithmetically averages the raw data D1 to D10 of ten tomographic images taken at the slice pitch “1 mm” to obtain an average value. The obtained average data AVD1 is written in a corresponding position in another buffer not shown.

When the reconstructing unit 63 reconstructs the raw data of the obtained addition-averaged tomographic image for one sheet, the addition-averaged tomographic image of the slice thickness "1 mm" is created.

As described above, raw data is arithmetically averaged and reconstructed to create a tomographic image after arithmetic averaging. By displaying the tomographic image, the number of images can be reduced and the image reading time can be shortened. Further, since the image information of the raw data corresponding to the plurality of tomographic images before arithmetic averaging is reflected in the tomographic image after arithmetic averaging, the amount of three-dimensional volume information does not decrease.

After storing a plurality of tomographic images before arithmetic averaging and a tomographic image after arithmetic averaging in the image storage section 15,
The same operation as that of the first embodiment as shown in FIGS. 8 and 9 can be performed.

Therefore, by having the display mode switching device 20, both the tomographic image before the averaging and the tomographic image after the averaging can be read. Further, by converting the number of tomographic images, a desired tomographic image after arithmetic averaging or a desired tomographic image before arithmetic averaging can be immediately obtained.

[Third Embodiment] Next, a third embodiment of the image display system of the present invention will be described. In the first embodiment, the averaging device 13 creates a tomographic image after averaging in the image display system. In the third embodiment, the averaging device 13 is provided in an X-ray CT device.

FIG. 13 shows a configuration diagram of the third embodiment of the image display system of the present invention. The X-ray CT apparatus 40b includes a gantry 41, an X-ray source 51, an X-ray detector group 53, and a data acquisition unit 5.
5, a reconstructing unit 56, an averaging device 13, a storage unit 57, and a display unit 58.

The image display system 10b includes a bus 11, a control unit 12, a slice conversion device 14, an image storage unit 15, a console 16, an image supplementary information storage unit 17, a display device 18, a slice number increasing / decreasing device 19, and a display mode switching. A device 20, an image transfer device 21, and a header information reading device 22 are provided.

That is, as shown in FIG. 13, X-ray CT
The arithmetic mean device 13 is provided between the reconstruction unit 56 and the storage unit 57 in the device 40b. When the reconstructing unit 56 obtains a plurality of tomographic images by reconstructing the helical scan data obtained by the data collecting unit 55, the averaging device 13 averages the plurality of tomographic images obtained by the reconstructing unit 56. By doing so, a tomographic image after averaging is created.

In this way, the tomographic image after the averaging obtained by the averaging device 13 is stored in the image storage section 15 in the image display system 10b. Then, by switching the display mode by the display mode switching device 20, a tomographic image after the averaging or a plurality of tomographic images before the averaging may be displayed on the display device 18.

[Fourth Embodiment] Next, a fourth embodiment of the image display system of the present invention will be described. In the second embodiment, the averaging device 13a is provided in the image display system.
A tomographic image after averaging was created by. The fourth embodiment is characterized in that the averaging device 13a is provided in an X-ray CT device.

FIG. 14 shows a block diagram of the fourth embodiment of the image display system of the present invention. The X-ray CT apparatus 40c includes a gantry 41, an X-ray source 51, an X-ray detector group 53, and a data acquisition unit 5.
5, the reconstruction unit 56, the averaging device 13a, the storage unit 57,
And a display unit 58.

The image display system 10c includes a bus 11, a control unit 12, a slice conversion device 14, an image storage unit 15, a console 16, an image supplementary information storage unit 17, a display device 18, a slice number increasing / decreasing device 19, and a display mode switching. A device 20, an image transfer device 21, and a header information reading device 22 are provided.

That is, as shown in FIG. 14, X-ray CT
The arithmetic mean device 13a is provided between the data collection unit 55 in the device 40c and the bus 11. In the averaging device 13a, the raw data averaging unit 61 includes the data collecting unit 55.
Raw data (helical scan data) for creating a plurality of tomographic images collected in step 1 is subjected to arithmetic averaging to create arithmetic mean raw data. Reconstruction unit 6
3 performs a reconstruction process on the raw data that is added and averaged by the raw data addition and averaging unit 61 to create a tomographic image after addition and averaging.

In this way, the tomographic image after the averaging obtained by the averaging device 13a is stored in the image storage section 15 in the image display system 10c. Then, by switching the display mode by the display mode switching device 20, a tomographic image after the averaging or a plurality of tomographic images before the averaging may be displayed on the display device 18.

[0132]

According to the present invention, since the averaging means averages a plurality of tomographic images and the tomographic image after the averaging is displayed on the display means, the number of images can be reduced and the interpretation time can be shortened. Further, since the image information of the plurality of tomographic images before the averaging is reflected in the tomographic image after the averaging, the amount of the three-dimensional volume information is not reduced.

Further, when the averaging means averages a plurality of tomographic images stored in the storage means and the display mode switching means switches the display mode, the reading means makes a plurality of tomographic images before the averaging based on the display mode. Alternatively, the tomographic image after the arithmetic averaging is read out, and the plurality of tomographic images before the arithmetic averaging or the tomographic image after the arithmetic averaging are displayed by the display means. As a result, a tomographic image can be selectively displayed according to the purpose by switching the display mode.

Further, the raw data for adding and averaging is created by performing the adding and averaging process on the raw data for creating a plurality of tomographic images of the subject, and the adding and averaging raw data is reconstructed and added. By creating an averaged tomographic image and displaying the averaged tomographic image, the number of images can be reduced and the reading time can be shortened.

The number of tomographic images can be converted between the number of tomographic images before arithmetic averaging and the number of tomographic images after arithmetic averaging.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of an image display system of the present invention.

FIG. 2 is a diagram illustrating a header portion of a tomographic image after arithmetic averaging according to the first embodiment.

FIG. 3 is a diagram illustrating a relationship among a slice pitch, a slice thickness, and an added number.

FIG. 4 is a diagram illustrating the number of added tomographic images.

FIG. 5 is a diagram illustrating an arithmetic mean of a plurality of tomographic images.

FIG. 6 is a diagram illustrating slice numbers of a tomographic image after averaging.

FIG. 7 is a diagram showing an appearance of the image display system according to the first embodiment of the present invention.

FIG. 8 is a flowchart illustrating an operation of displaying a tomographic image after averaging in the image display system according to the first embodiment of the present invention.

FIG. 9 is a flowchart illustrating an operation of displaying a tomographic image before averaging in the image display system according to the first embodiment of the present invention.

FIG. 10 is a diagram illustrating a tomographic image after addition and averaging that is displayed when the display mode is changed.

FIG. 11 is a configuration diagram showing a second embodiment of an image display system including the X-ray CT apparatus of the present invention.

FIG. 12 is a diagram illustrating a method of adding raw data.

FIG. 13 is a configuration diagram showing a third embodiment of an image display system including the X-ray CT apparatus of the present invention.

FIG. 14 is a configuration diagram showing a fourth embodiment of an image display system including the X-ray CT apparatus of the present invention.

FIG. 15 is a configuration diagram of a conventional image display system.

FIG. 16 is a diagram illustrating a header portion of a tomographic image before averaging.

FIG. 17 is a diagram showing an appearance of a conventional image display system.

FIG. 18 is a diagram illustrating an input method of an inspection number, the number of images of a selected inspection, and slice thickness.

[Explanation of symbols]

 81,16 Operation console 82,12 Control unit 83,15 Image storage unit 84,18 Display device 85,17 Image additional information storage unit 86,19 Slice number increasing / decreasing device 87,21 Image transfer device 88,22 Header information reading device 89 , 11 bus 13 averaging device 14 slice number conversion device 20 display mode switching device 35 display mode switching key 40a X-ray CT device 43 bed top 45 examinee 51 X-ray source 53 X-ray detector group 55 data acquisition unit 61 Raw data addition and averaging unit 56,63 Reconstruction unit 57 Storage unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taihei Kondo 1385-1 Shimoishigami, Otawara-shi, Tochigi Stock company Toshiba Nasu factory

Claims (5)

[Claims] 1. An averaging means for applying an averaging process to a plurality of tomographic images to create an averaging tomographic image, and a display means for displaying the tomographic image after the averaging created by the averaging means. An image display system comprising: 2. Storage means for storing a plurality of tomographic images before arithmetic averaging, and arithmetic averaging means for performing arithmetic averaging processing on the plurality of tomographic images stored in the storage means to create an arithmetic averaged tomographic image. And a display mode switching means for switching the display mode between a display mode for displaying the plurality of tomographic images before arithmetic averaging and a display mode for displaying the tomographic images after arithmetic averaging, and switching by the display mode switching means. Read-out means for reading out a plurality of tomographic images before arithmetic mean stored in the storage means or a tomographic image after arithmetic mean created by the arithmetic mean means based on the displayed display mode; and addition read by the reading means. An image display system, comprising: a display unit that displays a plurality of tomographic images before averaging or a tomographic image after averaging. 3. A raw data addition / averaging means for performing addition / averaging processing on raw data for producing the plurality of tomographic images to produce raw data subjected to addition / averaging, and the raw data addition The image display according to claim 1 or 2, further comprising: reconstruction means for performing reconstruction processing on the raw data subjected to the arithmetic mean by the averaging means to create the tomographic image after the arithmetic mean. system. 4. The averaging means according to claim 1 or 2, wherein the averaging means performs the averaging process on a plurality of tomographic images before the averaging by a predetermined number of sheets to be added. Image display system. 5. A number conversion unit for converting the number of tomographic images between the number of tomographic images before arithmetic averaging and the number of tomographic images after arithmetic averaging based on the previously designated number of added images. The image display system according to claim 4.