JPS63154156A - Image display apparatus for therapeutic plan - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention 1 (Field of Industrial Application) The present invention relates to an image display device for treatment planning used in medical diagnosis.

(Prior Art) In the medical field, it is well known that cancer treatments are carried out using radiation therapy equipment such as cobalt irradiation.

Conventionally, treatment planning devices that plan radiation therapy using both CT images have been put into practical use.

In the treatment planning device, the shape and position of a lesion is projected on a CT image, and an operator such as a doctor or radiology technician observes the lesion. This operator allows
The shape of the radiation aperture, the irradiation direction, etc. that are most suitable for the shape and position of the lesion are determined. FIG. 6 is a schematic explanatory diagram showing the relationship between the irradiation direction of a conventional radiation source and a subject. The aperture shape 22 refers to the area surrounded by the radiation shield 23, and the radiation from the radiation source 21 is emitted in the form of being projected toward the diseased IH in the subject M in the irradiation direction indicated by 'SJo. and then provided for treatment. Therefore, the determination of the shape 22 of this aperture plays an important role in determining the success or failure of treatment.

By the way, in the past, the image display of the shape and position of the lesion, which is necessary when determining the aperture shape 22, radiation irradiation direction Vo, etc., as described above, is performed using C as shown in FIG.
This was done only on T images. Incidentally, FIG. 7 is an explanatory diagram showing the operator's observation direction for both CT images.

To explain in detail based on FIGS. 6 and 7, the radiation is irradiated from the Y-axis direction below the lesion in the subject M, and the shape and position of the lesion T in the subject M is emitted. Only the cross section along the X-Y plane of both CT images is displayed for confirmation. Ml indicates the cross section of M in the X-Y plane, and Tl indicates the cross section of T in the X-Y plane.

As a result, the surface containing the aperture shape 22 and the lesion portion appearing on the lower C image are spatially shifted by 90 degrees, and the aperture shape 22 can be determined while observing both CT images. becomes extremely difficult.

In order to solve this difficulty,
It is desired to simultaneously observe both the simulator image obtained by irradiating radiation toward a plane and the CT image. Here, the simulator image refers to a radiographic image of the subject M that is modeled by a positioning device under the same geometric conditions as the irradiation conditions in the radiation therapy device prior to radiation therapy, Then, as shown in FIG. 8, the radiation film F is fixed in a position facing the focus P of the radiation source of the positioning device and the subject M, and parallel to the X-Z plane. This is a radiographic image of a subject M obtained on a radiation film F by irradiating the subject M with radiation from a focal point P.

As described above, the simulator image is a radiographic image of the subject M modeled from the Y-axis direction, but it is difficult to know the shape of the lesion T from this alone. This means that the difference in radiation absorption rate between normal tissue and lesion T of subject M is much smaller than the difference in radiation absorption rate between normal tissue and bone, and the difference does not appear on radiographic film F. It is based on this.

(Problems to be Solved by the Invention) As described above, with the conventional apparatus, it is difficult to grasp the three-dimensional shape of the target part of the subject, and as a result, there is a problem that the shape of the aperture for radiation cannot be appropriately determined. there were.

Therefore, the present invention enables observation of plane images perpendicular to the radiation irradiation direction in addition to plane images parallel to the radiation irradiation direction, making it easy to grasp the three-dimensional shape of the target area of the subject, and accurately and accurately determining the shape of the aperture. It is an object of the present invention to provide an image display device for treatment planning that allows effective decisions.

[Structure of the Invention] (Means for Solving the Problems) The treatment planning image display device of the present invention includes a storage unit that stores a tomographic image and a radiographic image obtained by irradiating a subject with radiation, and a storage unit that stores a tomographic image and a radiographic image obtained by irradiating a subject with radiation; an input unit for setting the shape of the region of interest, an arithmetic processing unit for obtaining a projection image of the set shape of the region of interest projected onto the radiographic image, and an image in which the radiographic image and the projection image are superimposed. The apparatus has a display section for displaying images, and the shape of the aperture to be placed in the radiation irradiation area is determined based on this superimposed image.

(for Kusaku) Next, the operation of the apparatus having the above configuration will be explained.

First, a tomographic image of a target region of the subject and a radiographic image of the subject obtained by irradiating the subject with radiation are stored in the storage unit.

Next, the operator of this apparatus displays the tomographic image on the display section and sets the shape of the region of interest by operating the input section. The shape of the set region of interest is taken into the @ calculation processing section, where a process for obtaining a projection image projected onto the radiographic image side is executed. Roughly speaking, the arithmetic processing unit executes a process of superimposing the historical image on the radiographic image,
The results are sent to the display section. As a result, an image in which both are superimposed is displayed on the display section, and is used as an image for determining the shape of the aperture.

(Example) Examples of the present invention will be described in detail below.

The embodiment device shown in FIG. 1 has a region of interest (
Region (HIntevest, hereinafter referred to as rROIj
RC)I shape input unit 1 such as a keyboard for setting a shape; a storage unit 2 that stores image information obtained by radiation irradiation to a subject; The display unit includes an arithmetic processing unit 3 that performs arithmetic processing such as There is.

The storage unit 2 stores radiation CT images obtained by irradiating the subject M with radiation (hereinafter referred to as "C lower side image")
A CT image storage unit 2a that stores information on a simulator image (radiotransparent image) obtained by irradiating the subject M with radiation, and
It is equipped with a simulator image storage section 2b that also stores the size of 1 pixel of this simulator image and the 7 coordinates of the center point of the screen when the simulator image is displayed.

The arithmetic processing unit 3 includes a CT image display processing unit 3a that takes in the CT image information and processes it for display, and a CT image display processing unit 3a that takes in the CT image information and processes it for display, and the CT image information that has been processed for display and the region of interest. information on the ROI on the CT image.
R converts the shape to the XY coordinate system and sends the result
OI coordinate processing section 3b and the simulator image storage section 2
The information on the simulator image from b is sent to the ROI coordinate processing unit 3.
a projected coordinate calculation unit 3c which takes in the processing results from the simulator image side and obtains a projection image by projecting the coordinate-transformed ROI shape onto the simulator image side using a processing routine that will be described in detail later; The display image processing unit 3d is provided with a display image processing unit 3d that performs processing to take in information on projected images and display them in a superimposed manner.

The first display section 4A is configured to display both CT images which are processed for display by the CT image display processing section 3a. Further, the second display section 4B is configured to display the superimposed image processed by the display image display processing section 3d.

Here, the processing routine in the projected coordinate calculating section 3c will be explained with reference to FIGS. 2 to 5.

Figure 2 shows the state of the subject M seen from the radiation source side during the CT image.
, as shown by line (3), is obtained as a tomographic structure in a plane parallel to the X-axis. In addition, in the same figure, the lower part shows the lesion part. Further, for example, both CT images taken along the line (1) in FIG. 2 are shown in FIG. 3.

Next, in Fig. 4, point P is the focus of the radiation source when the simulator image is shadowed, O is the origin of the XYZ coordinate system, and S
It is assumed that S is a plane containing the simulator image, point H is the center point of the simulator image, and plane S is perpendicular to the Y axis at point H. Further, the orientation of the simulator image is determined by matching the Z-axis orientation at the time of imaging shown in FIG. 8 with the Z-axis orientation at the time of CT image imaging shown in FIG. 2.

Based on this state, as shown in FIG. 4, the shape of both CT images ROf is set to a plane that is parallel to the XY plane and includes the Z axis, and the distance J! from the focal point P to the origin O is set. 1. Origin O
Find the distance 2 from to point H. Also, from focus P to R
O! Find the point A' where a straight line passing through one point A (Xl, "yl, Zl) intersects the plane S. If the - coordinates to this point are (x2°V2, Z2), then this coordinate (X
2. V2゜Then, by moving point A once around the ROI shape using a similar method and finding the locus of ゛ to the moving point relative to this, the shape of the projected image I in which the ROI shape is projected onto the plane S can be calculated. Be able to ask for it.

The process of obtaining the projected image T is performed based on the 7 coordinates and pixel size of the C image and the 7 coordinates and pixel size of the center point of the simulator image.

FIG. 5 shows @images 11, 12.I3 corresponding to the (11, (2), (3) lines) obtained on the plane S by the processing routine described above. This is a simulator image of the subject M shaded.

Next, the operation of the embodiment apparatus having the above configuration will be explained.

First, the operator of this equipment scans both CT and CT image information.
The image storage unit 2a stores the information of the simulator image, the 1 pixel size of the simulator image, the 7 coordinates of the center point of the image, and 11. and 12 are respectively stored in the simulator image storage section 2b.

The CT image information is displayed by the CT diagram display processing unit 3a and sent to the first display unit 4A, whereby the CT images including the lesion T portion of the subject M are displayed.

While observing this CT image, the operator examines the lesion cross section T1.
The ROI shape is input from the ROI input section 1.

The ROI coordinate processing section 3b takes in the information in the CT image corresponding to the RO shape from the CTT image display processing section 3a based on the information on the RO shape, coordinates transforms the information into the XY coordinate system, and calculates the result. is sent to the projected coordinate calculation unit 3C.

The projected coordinate calculating unit 3C executes a calculation to project the information on the ROI shape subjected to the coordinate transformation onto the plane S based on the processing routine, obtains information on the projected image I, and sends the result to the display image display processing unit 3d. Send.

The display image display processing section 3d takes in the information of the projection image (2), the information of the simulator image, its pixel information, and coordinate information from the simulator image storage section 2b, and displays the projection image I corresponding to the lesion part in the simulator image. The process of superimposing the position is executed and the result is displayed on the second display unit 4B.
Send to.

As a result, an image in which the simulator image and the projection image I accurately showing the lesion are superimposed is displayed on the second display unit 4B, and by observing this image, the operator can check the radiation irradiation area. The shape of the diaphragm to be placed can be determined accurately.

The present invention is not limited to the embodiments described above,
Various modifications are possible within the scope of the gist.

For example, in the above-mentioned embodiment, a case was explained in which two display sections were provided, but if the image obtained by superimposing both CT images can be switched and displayed at any time, it is possible to use a configuration using one display section. Can be implemented.

[Effects of the Invention] According to the present invention described in detail above, the three-dimensional shape of the target region of the subject can be easily and accurately grasped based on the tomographic image and the superimposed image. It is possible to provide a therapeutic image display device that can accurately determine the shape of an aperture for a radiation source.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an example device of the present invention, Fig. 2 is a schematic explanatory drawing showing the orientation of the subject and the shape of the lesion during CT image imprinting, and Fig. 3 shows just one example of the CT image. FIG. 4 is an explanatory diagram showing a state in which the ROI is projected onto the simulator image, FIG. 5 is an explanatory diagram showing a state in which the projected image is superimposed on the simulator image, and FIG. 6 is an explanatory diagram showing the state in which the projected image is superimposed on the simulator image. An explanatory diagram showing the positional relationship of the subject, FIG. 7 is an explanatory diagram showing the observation direction of both CT images, and FIG. 8 is an explanatory diagram showing the radiation source, the subject,
It is an explanatory view showing the positional relationship of radiation films. 1・
... ROI shape input unit, 2... storage unit, 3... arithmetic processing unit, 4A, 4B... first. Second display section, M...subject, ■...projected image. Agent Patent Attorney Yudo Chika
Norio Ogo Figure 3 Figure 6 procedural amendment (voluntary) 1. Indication of the case Japanese Patent Application No. 61-301368 2, Title of the invention Image display device for treatment planning 3, Person making the amendment Relationship to the case Patent applicant (307) Toshiba Corporation 4, Agent Address: Minato-ku, Tokyo 105 Shibaura-chome 1-1 (1) Detailed description of the invention in the specification column 6, Contents of amendment (1) Specification, page 6, line 19 r IntevestJ
is corrected with r InterestJ. (2) Lines 4 to 6 of page 10 of the specification are amended as follows. □Note□ Jll -Yl (However, 11 and, I!2 are scalars) and above

Claims (1)

[Claims] a storage unit that stores a tomographic image and a radiographic image obtained by irradiating a subject with radiation; an input unit that sets the shape of a region of interest for the tomographic image; and an input unit that sets a shape of a region of interest on the radiographic image side. and a display section that displays an image in which the radiation transmission image and the projection image are superimposed, and the radiation transmission area is arranged in the radiation irradiation area based on the superimposed image. An image display device for treatment planning, characterized in that the shape of the aperture is determined.