Radiation Therapy Positioning Device Based on Diagnostic Images

Abstract

The radiotherapy positioning device based on diagnostic images provided by the present invention establishes communication relationships with a hospital imaging system, a CT scanner, and a doctor's terminal respectively. The radiotherapy positioning device includes a treatment center point determination module, a positioning film acquisition module, an offset coordinate generation module, a marking processing module, and a precise positioning module. In the radiotherapy positioning device based on diagnostic images in this application, by acquiring positioning images at different angles during the positioning process and using a preset iterative registration algorithm to register the tumor diagnostic image with the first positioning image and the second positioning image, offset coordinates are obtained, and the offset coordinates are used for position adjustment to determine the body treatment center point corresponding to the target patient and obtain a precise positioning CT image, avoiding inaccurate positioning caused by limitations in positioning application information or insufficient personal experience of technicians.

Description

Technical Field

[0001] The present invention relates to the field of radiotherapy, and particularly to a radiotherapy positioning device based on diagnostic images. Background Art

[0002] With the continuous development of radiotherapy technology, it is statistically shown that about 65%-75% of cancer patients need radiotherapy. Radiotherapy is one of the three major means for treating cancer at present. The current radiotherapy has entered the "three-precision" era, namely precise positioning, precise planning, and precise treatment. Among them, precise positioning is the basis for realizing precise planning and precise treatment. As a positioning method in radiotherapy, CT simulation positioning technology has been widely applied in clinical practice. The CT simulation positioning system is particularly suitable for the positioning of tumors with complex clinical shapes or adjacent to important organs, as well as tumors that require multi-field irradiation or have complex dose curves for rotational irradiation.

[0003] The current CT simulation positioning process is as follows: For cancer patients who need radiotherapy, after the doctor diagnoses the tumor location through diagnostic CT, the patient needs to go to the positioning department for positioning first. The technician in the positioning department will, according to experience, stick positioning points for marking on the patient's body surface, and then perform a scanning and positioning CT again. When the positioning CT is scanning, due to the inaccurate positioning points stuck on the patient's body surface by the technician according to personal experience, there will be phenomena such as too short CT scanning area and incomplete coverage of the target area, thus affecting the subsequent precise plan design; or in order to cover the target area and increase the scanning area, the scanning time is increased, and at the same time, the patient receives more scanning dose and the patient continues to be scanned, which will cause discomfort to the patient; moreover, when the positioning origin during treatment obtained from the positioning points marked by the technician according to experience does not coincide with the treatment center point, resetting is required during the subsequent radiotherapy. The resetting process is cumbersome, error-prone, and will also introduce setup errors. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a radiotherapy positioning device based on diagnostic images, which can solve the problems that in the existing CT simulation positioning process, due to the inaccurate positioning points stuck on the patient's body surface by the technician according to personal experience, there will be phenomena such as too short CT scanning area and incomplete coverage of the target area, thus affecting the subsequent precise plan design and the need for resetting during the subsequent radiotherapy process.

[0005] The purpose of the present invention is achieved by adopting the following technical solutions:

[0006] A radiotherapy positioning device based on diagnostic images, the radiotherapy positioning device respectively establishes communication relationships with a hospital imaging system, a CT scanner, and a doctor terminal. The radiotherapy positioning device includes the following modules:

[0007] Treatment center determination module, which determines the treatment center point and scanning range for radiotherapy of the target patient according to the tumor diagnostic images in the preset database;

[0008] Localization film acquisition module, which sends a localization film scanning instruction to the CT scanner to scan the target patient to obtain a first localization image corresponding to the coronal plane and a second localization image corresponding to the sagittal plane, and the localization film acquisition module receives the first localization image and the second localization image sent by the CT scanner;

[0009] Offset coordinate generation module, which uses a preset iterative registration algorithm to register the tumor diagnostic image with the first localization image and the second localization image to obtain the offset coordinates of the current position of the target patient relative to the tumor diagnostic image;

[0010] Marking processing module, which sends the offset coordinates and a marking processing instruction to the doctor terminal. The marking processing instruction is to move the CT couch according to the offset coordinates so that the CT scanner points to the treatment center point position, and take the position on the target patient's body corresponding to the treatment center point as the body treatment center point, and perform marking processing on the body treatment center point;

[0011] Precise positioning module, which sends a precise positioning instruction to the CT machine. The precise positioning instruction is specifically to use the body treatment center point as the scanning center and perform CT scanning on the target patient according to the scanning range to obtain a precise positioning CT image for formulating a radiotherapy plan.

[0012] Furthermore, it further includes a diagnostic image acquisition module, which is used to acquire the tumor diagnostic image corresponding to the target patient from the hospital imaging system and save the tumor diagnostic image to the preset database.

[0013] Furthermore, the specific process of using the preset iterative registration algorithm to register the tumor diagnostic image with the first localization image and the second localization image is as follows:

[0014] Generate DRR images, generate DRR images corresponding to the first localization image and the second localization image according to the diagnostic CT image with the treatment center point as the origin and according to the preset mechanical parameters of the CT scanner;

[0015] Rigid registration, perform rigid body registration on the first localization image and the second localization image with the corresponding DRR images to obtain a first registration result;

[0016] Update the origin point, update the first registration result to the origin point, and determine whether the updated origin point converges. If it does, perform the step of generating offset coordinates. If not, return to perform the step of generating DRR images, and substitute the updated origin point into the step of generating DRR images;

[0017] Calculate the offset coordinates, and use the coordinate difference between the origin point at convergence and the treatment center point in the tumor diagnostic image as the offset coordinates.

[0018] Further, the DRR images include a first positioning DRR image corresponding to the first positioning image and a second DRR image corresponding to the first positioning image.

[0019] Further, the offset coordinates include the X-axis offset value, the Y-axis offset value, and the Z-axis offset value.

[0020] Further, the X-axis offset value is the offset value in the left-right direction corresponding to the two arms of the target patient, the Y-axis offset value is the offset value in the head-foot direction of the target patient, the Z-axis offset value is the offset value in the up-down direction corresponding to the body of the target patient. The marking processing instruction is specifically: move the CT table according to the Y-axis offset value and the Z-axis offset value to correct the position in the head-foot direction corresponding to the body of the target patient and the up-down direction corresponding to the body of the target patient, and correct the position in the left-right direction corresponding to the body of the target patient according to the X-axis offset value and through a PI-shaped ruler, so that the CT scanner points to the position of the treatment center point, take the position corresponding to the treatment center point on the body of the target patient as the body treatment center point, and perform marking processing on the body treatment center point.

[0021] Further, the determination of the treatment center point and the scanning range for radiotherapy of the target patient based on the tumor diagnostic image in the preset database is specifically: perform contouring processing on the tumor diagnostic image according to the preset target region automatic contouring algorithm to obtain the treatment center point and the scanning range, or receive the manually specified treatment center point and scanning range sent by the doctor terminal according to the tumor diagnostic image.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: In the radiotherapy positioning device based on diagnostic images in this application, before positioning the patient, the treatment center point and the scanning range are accurately confirmed according to the tumor diagnostic image corresponding to the target patient. Moreover, during the positioning process, positioning CT images at different angles are obtained, and a preset iterative registration algorithm is used to register the tumor diagnostic image with the first positioning image and the second positioning image to obtain the offset coordinates of the current position of the target patient relative to the tumor diagnostic image. The offset coordinates are used to adjust the position to determine the body treatment center point corresponding to the target patient. CT scanning is performed according to the body treatment center to obtain accurate positioning CT images for formulating radiotherapy plans, avoiding inaccurate positioning caused by insufficient personal experience of technicians, making the positioning CT diagnostic images for subsequent radiotherapy plans more accurate, thus obtaining a relatively accurate treatment plan. During the later radiotherapy, there is no need to perform a reset process, avoiding the risk of setup errors caused by reset operations and simplifying the radiotherapy process.

[0023] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly and implement it in accordance with the content of the specification, the following takes the preferred embodiments of the present invention and describes them in detail in conjunction with the accompanying drawings. The specific implementation manners of the present invention are given in detail by the following embodiments and their accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are used to provide a further understanding of the present invention and form a part of this application. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0025] Figure 1 It is a schematic diagram of the working process of the radiotherapy positioning device based on diagnostic images of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] Next, in combination with the accompanying drawings and specific implementation manners, the present invention will be further described. It should be noted that, on the premise of no conflict, the following-described embodiments or technical features can be combined arbitrarily to form new embodiments.

[0027] As Figure 1 shown, in the radiotherapy positioning device based on diagnostic images in this application, the radiotherapy positioning device respectively establishes communication relationships with the hospital imaging system, the CT scanner, and the doctor terminal. The radiotherapy positioning device includes the following modules:

[0028] Diagnostic image acquisition module. The diagnostic image acquisition module is used to acquire the tumor diagnostic image corresponding to the target patient and save the tumor diagnostic image to a preset database. In this embodiment, the tumor diagnostic image corresponding to the target patient is pre-sent to the diagnostic image acquisition module through the hospital imaging system, and the diagnostic image acquisition module saves it to the preset database. In the preset database, the tumor diagnostic image is bound to the personal information of the target patient for subsequent query. The above-mentioned tumor diagnostic image is a diagnostic image such as a tumor diagnostic CT image, a tumor diagnostic MRI image, or a tumor diagnostic ultrasound image that the target patient has undergone.

[0029] Treatment center point determination module. The treatment center point determination module determines the treatment center point and scanning range for radiotherapy of the target patient according to the tumor diagnostic image in the preset database. In this step, specifically, the tumor diagnostic image is processed by a preset target area automatic delineation algorithm to obtain the treatment center point and scanning range, or the manually specified treatment center point and scanning range sent by the doctor according to the tumor diagnostic image through the doctor terminal are received.

[0030] Localization film acquisition module. The localization film acquisition module sends a localization film scanning instruction to the CT scanner to scan the target patient to obtain a first localization image corresponding to the coronal plane and a second localization image corresponding to the sagittal plane. The localization film acquisition module receives the first localization image and the second localization image sent by the CT scanner. The localization film scanning instruction is specifically: scanning the target patient to obtain a first localization image corresponding to the coronal plane and a second localization image corresponding to the sagittal plane. The coronal plane is the section obtained when the X-ray tube in the CT scanner is located at the top of the target patient, and the sagittal plane is the section obtained when the X-ray tube in the CT scanner is located on the side of the target patient. In this example, the instrument in the CT scanner for scanning the target patient is the X-ray tube that emits rays and the detector. When scanning, the X-ray tube and the detector are arranged opposite to each other, that is, the detector is located opposite the X-ray tube to receive the rays that return after passing through the target patient's body. The X-ray tube is essentially an X-ray tube, and the detector is a flat panel detector. When the X-ray tube is located at different relative positions of the target patient lying on the CT bed, images at different angles will be taken. In this embodiment, the coronal plane scan is the localization image obtained when the X-ray tube in the CT scanner is located at the top of the target patient's body and the detector is located opposite the X-ray tube (i.e., at the bottom of the target patient's body). At this time, the scanning angle is also called 0-degree scan in the CT scanning field, and the obtained localization image is the first localization image; the sagittal plane scan is the localization image obtained when the X-ray tube in the CT scanner is located on the side of the target patient's body, that is, in the left-right direction, and the detector is located opposite the X-ray tube (i.e., on the other side of the target patient's body). At this time, the scanning angle is also called 90-degree scan in the CT scanning field, and the obtained localization image is the second localization image.

[0031] An offset coordinate generation module, which uses a preset iterative registration algorithm to register the tumor diagnostic image with the first localization image and the second localization image, and obtains the offset coordinates of the current position of the target patient relative to the tumor diagnostic image. The specific steps of using the preset iterative registration algorithm to register the tumor diagnostic image with the first localization image and the second localization image in this embodiment are as follows:

[0032] Generate DRR images. According to the diagnostic CT image, with the treatment center point as the origin and in accordance with the preset mechanical parameters of the CT scanner, generate DRR images corresponding to the first localization image and the second localization image. The DRR images include a first localization DRR image corresponding to the first localization image and a second DRR image corresponding to the first localization image; In this step, the treatment center point is set as the origin O 0 , the first localization image is set as DR 0 , the second localization image is set as DR 90 , the first generated first localization DRR image is set as The first generated second localization image is set as

[0033] Rigid registration. Perform rigid body registration on the first localization image and the second localization image with the corresponding DRR images to obtain a first registration result. The first registration result includes the registration results of the first localization image with the first localization DRR image and the second localization image with the second localization DRR image; In this embodiment, perform rigid body registration on DR 0 and as well as DR 90 and respectively; Denote the registration result of DR 0 and as: (Registration result of the first localization image with the first localization DRR image), is the X-axis offset value, is the Y-axis offset value. The registration result of DR 90 and is: (Registration result of the second localization image with the second localization DRR image), is the Y-axis offset value, is the Z-axis offset value. Then the first registration result is:

[0034] Update the origin, update the first registration result to the origin, and determine whether the updated origin converges. If it does, execute the step of generating offset coordinates. If not, return to execute the step of generating DRR images, and substitute the updated origin into the step of generating DRR images; let the updated origin be O 1 , then O 1 = O 0 +(dx 0 , dy 0 , dz 0 ). In this step, it is necessary to determine whether the updated origin converges. If convergence exists, directly calculate the offset coordinates. If not, the updated origin is used as the origin in the step of generating DRR images, and repeat the above steps of generating DRR images and rigid registration steps.

[0035] Calculate the offset coordinates, and use the coordinate difference between the origin at the time of convergence and the treatment center point in the tumor diagnostic image as the offset coordinates. Assume the origin at the time of convergence is O n , then O n minus O 0 is the coordinate offset of the two groups of images, denoted as dx, dy, dz. Among them, dx represents the offset value in the left - right direction of the target patient (i.e., the offset value on the X - axis), dy represents the offset value in the head - foot direction of the target patient (Y - axis offset value), and dz represents the offset value in the up - down direction of the target patient (Z - axis offset value).

[0036] A marking processing module, which sends the offset coordinates and marking processing instructions to the doctor's terminal. The marking processing instructions are to move the CT table according to the offset coordinates so that the CT scanner points to the treatment center point position, take the position on the target patient's body corresponding to the treatment center point as the body treatment center point, and perform marking processing on the body treatment center point. Correct the position in the head - foot direction corresponding to the target patient's body and the position in the up - down direction corresponding to the target patient's body by moving the CT table according to the offset value in the head - foot direction of the target patient (Y - axis offset value) and the offset value in the up - down direction of the target patient (Z - axis offset value), and correct the position on the left - right of the target patient's body according to the offset value in the left - right direction corresponding to the two arms of the target patient and through a PI - shaped ruler, so that the CT scanner points to the treatment center point position, take the position on the target patient's body corresponding to the treatment center point as the body treatment center point, and perform marking processing on the body treatment center point.

[0037] Precise positioning module, the precise positioning module sends a precise positioning instruction to the CT machine. The precise positioning instruction specifically takes the body treatment center point as the scanning center, performs CT scanning on the target patient according to the scanning range, obtains a precise positioning CT image for formulating a radiotherapy plan, and places the center point of the accelerator at the position indicated by the marking point; during radiotherapy, the positioning is directly performed according to the position of the marking point.

[0038] The radiotherapy positioning device based on diagnostic images in the present application accurately determines the treatment center point and scanning range according to the tumor diagnostic image corresponding to the target patient before positioning the patient. Moreover, during the positioning process, positioning CT images at different angles are obtained, and the preset iterative registration algorithm is used to register the tumor diagnostic image with the first positioning image and the second positioning image to obtain the offset coordinates of the current position of the target patient relative to the tumor diagnostic image. The offset coordinates are used for position adjustment to determine the body treatment center point corresponding to the target patient, and CT scanning is performed according to the body treatment center to obtain a precise positioning CT image for formulating a radiotherapy plan, avoiding inaccurate positioning caused by insufficient personal experience of technicians, making the positioning CT diagnostic image for the subsequent radiotherapy plan more accurate, thus obtaining a more accurate treatment plan. During the subsequent radiotherapy, there is no need for a reset process, avoiding the risk of positioning error caused by the reset operation and simplifying the radiotherapy process.

[0039] The above are only the preferred embodiments of the present invention and do not impose any form of limitation on the present invention; any ordinary technician in the industry can smoothly implement the present invention according to the instructions in the attached drawings and the above; however, any minor changes, modifications, and equivalent changes made by those skilled in the art within the scope of the technical solution of the present invention using the technical content disclosed above are equivalent embodiments of the present invention; at the same time, any equivalent changes, modifications, and evolutions made to the above embodiments based on the essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A radiotherapy positioning device based on diagnostic images, characterized in that: The radiotherapy positioning device establishes communication relationships with a hospital imaging system, a CT scanner, and a doctor's terminal respectively. The radiotherapy positioning device includes the following modules: A treatment center point determination module, which determines the treatment center point and the scanning range for radiotherapy of a target patient according to the tumor diagnostic images in a preset database; A positioning film acquisition module, which sends a positioning film scanning instruction to the CT scanner to scan the target patient to obtain a first positioning image corresponding to the coronal plane and a second positioning image corresponding to the sagittal plane. The positioning film acquisition module receives the first positioning image and the second positioning image sent by the CT scanner; An offset coordinate generation module, which uses a preset iterative registration algorithm to register the tumor diagnostic image with the first positioning image and the second positioning image to obtain the offset coordinates of the current position of the target patient relative to the tumor diagnostic image; A marking processing module, which sends the offset coordinates and a marking processing instruction to the doctor's terminal. The marking processing instruction is to move the CT table according to the offset coordinates so that the CT scanner points to the treatment center point position, and take the position on the target patient's body corresponding to the treatment center point as the body treatment center point, and perform marking processing on the body treatment center point; A precise positioning module, which sends a precise positioning instruction to the CT machine. The precise positioning instruction is specifically to use the body treatment center point as the scanning center and perform CT scanning on the target patient according to the scanning range to obtain a precise positioning CT image for formulating a radiotherapy plan.

2. The radiotherapy positioning device based on diagnostic images according to claim 1, characterized in that: It further includes a diagnostic image acquisition module, which is used to acquire the tumor diagnostic image corresponding to the target patient from the hospital imaging system and save the tumor diagnostic image to a preset database.

3. The radiotherapy positioning device based on diagnostic images according to claim 1, characterized in that: The specific process of using the preset iterative registration algorithm to register the tumor diagnostic image with the first positioning image and the second positioning image is as follows: Generate a DRR image. Generate a DRR image corresponding to the first positioning image and the second positioning image according to the diagnostic CT image with the treatment center point as the origin and according to the preset mechanical parameters of the CT scanner; Rigid registration. Perform rigid body registration on the first positioning image and the second positioning image with the corresponding DRR images to obtain a first registration result; Update the origin. Update the first registration result to the origin, and judge whether the updated origin converges. If so, execute the step of generating offset coordinates. If not, return to execute the step of generating a DRR image, and substitute the updated origin into the step of generating a DRR image; Calculate the offset coordinates. Take the coordinate difference between the origin at the time of convergence and the treatment center point in the tumor diagnostic image as the offset coordinates.

4. The radiotherapy positioning device based on diagnostic images according to claim 3, It is characterized in that: The DRR images include a first positioning DRR image corresponding to the first positioning image and a second DRR image corresponding to the first positioning image.

5. The radiotherapy positioning device based on diagnostic images according to claim 3, It is characterized in that: The offset coordinates include an X-axis offset value, a Y-axis offset value, and a Z-axis offset value.

6. The radiotherapy positioning device based on diagnostic images according to claim 5, It is characterized in that: The X-axis offset value is the offset value in the left-right direction corresponding to the two arms of the target patient, the Y-axis offset value is the offset value in the head-foot direction of the target patient, the Z-axis offset value is the offset value in the up-down direction corresponding to the body of the target patient, and the marking processing instruction is specifically: move the CT table according to the Y-axis offset value and the Z-axis offset value to correct the position in the head-foot direction corresponding to the body of the target patient and the up-down direction corresponding to the body of the target patient, and correct the position in the left-right direction corresponding to the body of the target patient according to the X-axis offset value and through a PI-shaped ruler, so that the CT scanner points to the treatment center point position, take the position corresponding to the treatment center point on the body of the target patient as the body treatment center point, and perform marking processing on the body treatment center point.

7. The radiotherapy positioning device based on diagnostic images according to claim 1, It is characterized in that: The determination of the treatment center point and the scanning range for radiotherapy of the target patient according to the tumor diagnostic image in the preset database is specifically: performing contouring processing on the tumor diagnostic image according to the preset target area automatic contouring algorithm to obtain the treatment center point and the scanning range, or receiving the treatment center point and the scanning range manually specified by the doctor's terminal according to the tumor diagnostic image.

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