JPH0471541A - Radioactive ray therapeutic system - Google Patents

Abstract

PURPOSE:To perform a radioactive ray therapy without trouble with a system in any combination of apparatuses by converting the obtained image information of a film into digital signals, correcting them, then generating fluoroscopic image and target image data. CONSTITUTION:A person under test is admitted into an X-ray CT 1, the image data of the tomographic image are collected, and the image on the CRT of a film imager 3 is photographed to generate a film. The film is sent to an image scanner 5 and installed on a film setting base, the light with a fixed wavelength is radiated to the film and permeated, and the permeated light quantity is detected by a photo-sensor and outputted as a digital signal. The signal is inputted to a film simulator 6, various corrections are performed, and the permeation image with the same focal point size as that of a radioactive ray therapeutic machine 4 is generated from multiple tomographic image data after corrections. The target image of the radioactive ray therapeutic machine 4 is generated from the tomographic image. This digitized information is sent to a therapeutic machine controller 7. The controller 7 controls the radioactive ray therapeutic machine 4 to radiate radioactive rays for therapy based on the received information.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a radiotherapy system for radiotherapy, and particularly to a radiotherapy system that can utilize image information from any image diagnostic apparatus.

(Conventional technology) Ever since linear accelerators were introduced for cancer treatment,
Radiation therapy machines using various types of radiation have appeared, and R I
(Radio l5otope) treatment devices and heavy ion particle treatment devices have been successively developed and used. With the development of high-energy radiation therapy, which has remarkable therapeutic effects, emphasis has been placed on highly accurate radiation therapy systems. As the therapeutic effects of radiation therapy machines are remarkable, there is an increasing need to reduce radiation to areas other than the affected area as much as possible and position the area to be treated accurately so that only the affected area is irradiated.

(Problems to be Solved by the Invention) By the way, as devices for positioning the affected area, there are portable X-ray imaging systems, angiography fluoroscopy systems, and X-ray CT systems.
There are devices, MRI systems, etc., each of which can output digital signals, but these output signals have different formats or are compressed depending on the manufacturer, so unless the specifications are made public,
The output signal cannot be directly received and used.

Even in the devices that output digital signals as described above, a doctor or the like who needs to make a diagnosis always outputs image information using film. An example of this device is shown in FIG. In the figure, 1 is an X-ray CT that is commonly used for taking tomographic images of patients. 2 is an X-ray simulator for obtaining a fluoroscopic image of a patient and viewing the affected area; 3 is a film imager for receiving tomographic image data from the X-ray CT 1 and fluoroscopic image data from the X-ray simulator 2 and outputting a film image. It is. The doctor reads the film, marks the patient's body surface, and sends it to the radiation therapy machine 4.
The patient is placed on a table, the irradiation range is set, and direct irradiation is performed. With this method, it is difficult to align a plurality of tomographic images, and it is also difficult to compare films taken with different devices.

The present invention has been made in view of the above points, and its purpose is to configure a radiotherapy system by combining medical image diagnostic devices from different manufacturers, in which digital signals cannot be used due to differences in format, etc. In many cases, the image data is output in the form of film, or even if it is obtained with any equipment with different specifications, it is always converted into digital information under the same conditions and converted into an image, and the image data for radiation therapy is processed. The objective is to realize a radiation therapy system that can output .

(Means for Solving the Problems) The present invention solves the above problems by using an X-ray CT that irradiates X-rays to obtain image data of a plurality of tomographic planes and outputs at least the following information; (b) Information on tomography position display (b) Text information such as patient identification number, patient name, imaging number, tomogram imaging interval, etc. (c) Image center display mark (d) Display of gray scale and its value and CTO Value position display (e) Actual length conversion scale An image scanner that reads an image on a film created by a film imager that creates an image on film based on information from the X1iCT and converts it into digital image information, and the image scanner. Correction of nonlinearity on the film of the image information of the digitized tomographic image and correction of errors in digitization that occur based on the ambient temperature are performed, and a target image for treatment by the radiation therapy machine is created. The present invention is characterized by comprising a film simulator that performs processing such as creating a transmission image with the same focal size as the radiation therapy machine, setting an ROI, and creating a fan beam for the radiation therapy machine.

(Function) Tomographic image data and various image information collected by X-ray CT are
Film Imager creates a film image. Next, it is installed on the film setting table of an image scanner and converted into a digital signal. The film simulator performs various corrections on this digital signal, creates a transmission image, a target image, etc., and determines the range of radiation irradiation by the radiation therapy machine.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

In the figure, 1 is an X-ray CT shown by a conventional device, but in this embodiment, in addition to tomographic image data, X19CT1 is information indicating a tomography position to be displayed on a transmission image to be created in the future; patient identification number, patient name, imaging number,
Information such as text information such as the imaging interval of the tomographic film, image center display mark, display of gray scale and its value (window width, window level W, position on the gray scale of CTO value), actual length conversion scale, etc. Output to Imager 3. An example of a tomographic film produced by the film imager 3 is shown in FIG. In the figure, 21 is
This is a tomographic image obtained by line CTI and imaged by a film imager 3. 22 is the patient name.

Character information such as shooting date, etc., 23 is a gray scale that is the standard for image density, and the density of CTO value is blur scale 23
It is marked * above. Reference numeral 24 denotes an image center display mark, which is written on each film, and by aligning this mark, the positions of all films are aligned. 25 is a density display indicating window conditions and the position of the CTO value; 26 is an actual length conversion scale between the length of the tomographic image on the film and the length of the real image; and 27 is a CTO value display mark indicating the CTO value on the gray scale 23. It is.

Step 5 is to place the film obtained by the film imager 3 at a predetermined position, irradiate it with light from a light source that emits light of a certain wavelength, and detect changes in the amount of light as an image of the light transmitted through the film using an optical sensor. This is an image scanner that digitizes image information. A standard button is provided for calibrating the shading of the film and the output of the image scanner 5 during the digitization process.

FIG. 3 is a diagram showing the film setting table 51 of the image scanner 5. As shown in FIG. In the figure, 52 is a film setting position for placing a film on it and irradiating light from above;
Reference numeral 3 designates a center setting position mark for determining the position of the film by matching it with the image center display mark 24 of the film shown in FIG.

6 is applied to image data digitized by the image scanner 5, which is caused by correction of errors due to non-linearity of the image scanner 5, correction of non-linearity between shading and light amount on the film, and changes in ambient temperature. Performs digital conversion error correction, etc., creates a target image showing the affected area necessary for treatment performed by the radiation therapy machine 4, creates a transmitted image with the same focal size as the radiation therapy machine 4, and creates ROI on the transmitted image This is a film simulator that performs settings such as setting and creating a fan beam that sets the limit range of radiation irradiation by the radiation therapy machine 4.

A treatment machine controller 7 controls the table, collimator, and gantry of the radiation treatment machine 4 based on information from the film simulator 6. Information is transmitted between the film simulator 6 and the treatment machine controller 7 by using a modem (modulator/demodulator) or optical transmission means.
The equipment including the film simulator 6, the treatment machine controller 7, and the radiation treatment machine 4 can be installed in isolated positions.

Next, the operation of the embodiment configured as described above will be explained. A subject is accommodated in the X-ray CTI, and a position including the affected area is irradiated with X-rays to collect tomographic image data and displayed on the CRT of the film imager 3. The film imager 3 takes the image on this CRT and creates a film. X
The ray CTI then changes the X-ray irradiation position, collects data, and creates a film using the film imager 3. Repeat this operation as many times as necessary. When displaying an image on a CRT, press
Along with the image data, the line CT1 includes character information such as the patient identification number, patient name, imaging number, and tomographic imaging interval shown in FIG.
Information on tomography position display, image center display mark, density display such as gray scale and its value, and CTO value position,
Information such as the actual length conversion scale is displayed on the C of Film Imager 3.
The image on the CRT is photographed by a camera and displayed on film. The film of the tomographic photograph created here shown in FIG. Installed at
Output as a digital signal. At this time, since the shading of the film and the output of the image scanner 5 do not necessarily maintain a perfect proportional relationship, this characteristic is calibrated in advance using a standard pattern.

Digital signals from the image scanner 5 are input to a film simulator 6. The film simulator 6 corrects the input digital signal using the nonlinearity data of the image scanner 5 and the nonlinearity data of the film, which are known in advance, and also changes the input signal to a digital signal depending on the ambient temperature. Correct this if it occurs.

In order to align the data of a plurality of tomographic films, the data of the image center display mark 24 included in the output signal of the image scanner 5 is collated to align the positions of all images. A transmission image with the same focal size as the radiation therapy machine 4 is created from a plurality of corrected tomographic image data obtained by performing various corrections in this manner. An example of this image is shown in FIG. In the figure, parts equivalent to those in FIG. 2 are given the same reference numerals. In the figure, 61 is a character display area that displays character information such as patient identification number, patient name, imaging number, and imaging interval of tomographic images, 62 is a reference position slice plane that represents the reference position of the slice plane with a line, and 63 is a plurality of slice planes. The tomographic image slice position is expressed by a line indicating the position of the slice plane of the tomographic image, and is expressed by the distance from the reference position slice plane 62. Furthermore, a target image for the radiation therapy machine 4 is created from the tomographic image, an ROI is set, a fan beam for the radiation therapy machine 4 is created, etc.

This fan beam identifies the irradiation area on the image so that radiation does not irradiate the affected area when it is close to an important organ.

The digitized information with various corrections added in this way is sent to the treatment machine controller 7. Based on the received information, the treatment machine controller 7 controls the table, collimator, and gantry of the radiation treatment machine 4 to position the patient lying on the table and to open the aperture of the collimator to selectively irradiate the affected area. In addition, the rotation angle of the gantry, the irradiation direction, etc. are set. Thereafter, the radiation therapy machine 4 irradiates the patient with radiation to perform treatment.

As explained above, according to this embodiment, even when information in different formats is output from photographic systems made by different manufacturers, the obtained film image information is converted into digital signals and various corrections are performed. By subsequently creating fluoroscopic image and target image data, radiation therapy can be performed without any problems using a system using any combination of devices.

(Effects of the Invention) As described above in detail, the present invention can be applied to a radiation therapy system using any combination of medical image diagnostic devices of different formats to obtain image data for radiation therapy. The practical effect is great.

[Brief explanation of the drawing]

Figure 1 is a block diagram of an embodiment of the present invention, Figure 2 is a diagram of a tomographic film obtained by a film imager, Figure 3 is a diagram of the film setting table of the image scanner, and Figure 4 is a film simulator. FIG. 5 is a block diagram of a conventional radiotherapy system. 1. X-ray CT 3. Film imager 4.
...Radiotherapy machine 5...Image scanner 6...Film simulator 7...Treatment machine controller 22...Text information 23・Gray scale 24・
・Image center display mark 25...Density display 26...Actual length conversion scale 27
... CTO value table hidden mark ... Film setting table 52 ... Film installation position 53 ... Center setting position mark 61 ... Character display area 62 ... Reference position slice plane 63 ... Tomographic image slice position Diagram

Claims (1)

[Claims] An X-ray CT (1) that irradiates X-rays to obtain image data of a plurality of tomographic planes and outputs at least the following information:
(a) Information on tomography position display (b) Character information such as patient identification number, patient name, imaging number, tomogram imaging interval, etc. (c) Image center display mark (d) Gray scale and its value Display and CTO value position display (e) Actual length conversion scale Digital image information is obtained by reading the image on the film created by the film imager (3) which creates an image on film based on the information from the X-ray CT (1). an image scanner (5) that converts the image information of the tomographic image digitized by the image scanner (5), and correction of non-linearity on the film of the image information of the tomographic image digitized by the image scanner (5), correction of digitization errors occurring based on ambient temperature, etc. , create a target image for treatment with the radiation therapy machine (4), create a transmitted image with the same focal size as the radiation therapy machine (4), set the ROI, and perform the following steps:
1. A radiation therapy system comprising: a film simulator (6) that performs processing such as creating a fan beam.