A daily inspection method integrating CyberKnife dose and mechanical accuracy

Abstract

The invention discloses an integrated daily inspection method for CyberKnife dose and mechanical accuracy, comprising: obtaining a verification plan dose distribution map and a target dose-grayscale curve map of the CyberKnife; inserting an EBT3 film to be inspected into an AQA phantom; obtaining a positioning error of the AQA phantom and adjusting it; irradiating the EBT3 film; scanning the irradiated EBT3 film to obtain a grayscale map of the EBT3 film; converting the grayscale map of the EBT3 film based on the target dose-grayscale curve map to obtain a dose map of the EBT3 film, so as to determine the dose map of the EBT3 film and the CyberKnife dose in the verification plan dose distribution map; performing image registration based on the dose map of the EBT3 film and the verification plan dose distribution map, analyzing the dose map of the EBT3 film, obtaining the CyberKnife dose and mechanical accuracy, shortening the quality control time, and effectively improving the daily inspection efficiency of the CyberKnife.

Description

Technical Field

[0001] The present invention relates to the field of medical technology, and more specifically, to a daily inspection method for integrating CyberKnife dosage and mechanical accuracy. Background Art

[0002] CyberKnife is a new type of radiotherapy equipment used for whole-body tumors. It is a device specifically used for low-fractionation, high-dose stereotactic radiotherapy treatment. This mode has more advantages in local tumor control, but the potential risk of endangering organs is also higher, so the performance requirements of radiotherapy equipment will be higher. In order to prevent radiotherapy accidents, CyberKnife requires more stringent quality assurance and quality control methods to ensure the safety and accuracy of radiotherapy. Therefore, daily inspection of accelerators is an important part of radiotherapy equipment quality control before patient treatment. Daily inspection allows quality control physicists to find out whether the equipment is working properly and deal with problems found in a timely manner, thereby preventing unnecessary risks and losses to radiotherapy patients, radiation workers and radiotherapy equipment.

[0003] Daily inspection mainly includes accelerator status detection, output dose stability detection and mechanical accuracy detection. The dose output stability detection usually uses an ionization chamber to measure the point dose at the center of the field and compare it with the baseline value of the accelerator acceptance test, requiring a deviation of ≤±2%. The mechanical accuracy uses the AQA phantom to detect the mechanical accuracy of the accelerator and the image tracking system, requiring a tolerance of ≤0.95mm. These two tests and data analysis take 20-25 minutes. The detection process is complicated and takes longer than other conventional accelerators. In addition, the AQA phantom test can only detect the mechanical accuracy of the CyberKnife, and cannot achieve dose verification. The reason is that the AQA film can only detect the information of the mechanical accuracy of the accelerator and cannot reflect the accuracy of the dose.

[0004] Since the CyberKnife treatment time for each patient is very long, the number of patients treated daily is very limited. If the daily morning check-up time can be increased, more treatment time can be left for patients, allowing more patients to receive high-quality radiotherapy.

[0005] Therefore, how to provide a daily inspection method that integrates CyberKnife dose and mechanical accuracy has become a technical problem that urgently needs to be solved in this field. Summary of the invention

[0006] An object of the present invention is to provide a new technical solution for a daily inspection method integrating CyberKnife dosage and mechanical accuracy.

[0007] According to a first aspect of the present invention, a method for daily inspection of CyberKnife dose and mechanical accuracy is provided, comprising the following steps:

[0008] Obtain the CyberKnife verification plan dose distribution diagram and CyberKnife target dose-grayscale curve diagram;

[0009] Insert the EBT3 film to be tested for radiometric determination into the spherical square of the automatic quality assurance deviation detection body AQA phantom;

[0010] Obtain the positioning error of the AQA phantom;

[0011] Based on the positioning error of the AQA phantom, adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed;

[0012] Irradiate the EBT3 film;

[0013] Scan the irradiated EBT3 film to obtain a grayscale image of the EBT3 film;

[0014] Converting the grayscale image of the EBT3 film based on the target dose-grayscale curve to obtain a dose image of the EBT3 film;

[0015] Image registration is performed based on the dose map of the EBT3 film and the dose distribution map of the verification plan. The dose map of the EBT3 film is analyzed to obtain the accuracy of the CyberKnife dose and the machine.

[0016] Optionally, the target dose-grayscale curve diagram of CyberKnife comprises the following steps: annotating number information and dose information on a plurality of target EBT3 films;

[0017] irradiating a plurality of the target EBT3 films based on the dose information of each of the target EBT3 films;

[0018] Scanning the irradiated target EBT3 film to obtain a plurality of grayscale images;

[0019] A target dose-grayscale curve diagram is established based on the dose information and the plurality of grayscale images.

[0020] Optionally, after obtaining the plurality of grayscale images, the method further includes the following steps: performing noise and non-uniformity correction processing on the plurality of grayscale images.

[0021] Optionally, a high-resolution scanner is used to scan the irradiated target EBT3 film, with parameters of 48-bit true color, 72 dpi resolution, and no color correction.

[0022] Optionally, the dose information of the plurality of target EBT3 films is 0.1Gy, 0.25Gy, 0.5Gy, 1Gy, 2Gy, 4Gy, 6Gy and 9Gy respectively.

[0023] Optionally, the obtaining of the CyberKnife verification plan dose distribution map comprises the following steps:

[0024] Prepare standard EBT3 film;

[0025] Performing CT scanning on the standard EBT3 film to obtain a CT image;

[0026] A spherical target area and a target area standard dose are set in the AQA phantom, and low-resolution optimization and high-resolution calculation are performed on the target area standard dose to obtain a verification plan dose distribution diagram of CyberKnife.

[0027] Optionally, the EBT3 film to be tested for radiation dosimetry without processing is inserted into the spherical square of the automatic quality assurance deviation detection body AQA phantom, comprising the following steps:

[0028] Inserting the EBT3 film to be tested into the spherical cube located in the fixed water of the AQA phantom;

[0029] The AQA phantom is positioned and adjusted to ensure that the cross center line of the solid water surface coincides with the positioning laser light line.

[0030] Optionally, the obtaining of the positioning error of the AQA phantom and adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom include the following steps:

[0031] Taking a first orthogonal image of the AQA phantom to obtain a positioning error of the AQA phantom;

[0032] The position of the five-dimensional treatment bed is corrected based on the AQA phantom positioning error.

[0033] Optionally, the obtaining of the positioning error of the AQA phantom and adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom further includes the following steps:

[0034] Taking a second orthogonal image of the AQA phantom to obtain a horizontal plane rotation error of the first AQA phantom;

[0035] Correcting the position of the AQA phantom based on the horizontal plane rotation error of the first AQA phantom;

[0036] Taking a third orthogonal image of the AQA phantom to obtain a horizontal plane rotation error of the second AQA phantom;

[0037] If the horizontal plane rotation error of the second AQA phantom meets the preset error, the EBT3 film is irradiated.

[0038] Optionally, the dose map based on the EBT3 film is image-registered with the dose distribution map of the verification plan, and the dose map of the EBT3 film is analyzed to obtain the CyberKnife dose and mechanical accuracy, including the following steps:

[0039] Perform image registration between the dose map of the EBT3 film and the dose distribution map of the verification plan;

[0040] The dose map of the EBT3 film registered with the dose distribution map of the verification plan was analyzed to obtain the position offset and dose deviation value of the CyberKnife.

[0041] The CyberKnife dose and mechanical accuracy are determined based on the CyberKnife position offset and dose deviation values.

[0042] The beneficial effects of the present invention are:

[0043] 1. The present invention can simultaneously detect the dosage accuracy and mechanical accuracy of the CyberKnife, shorten the quality control time, and effectively improve the daily inspection efficiency of the CyberKnife, thereby increasing the number of patients treated by the CyberKnife every day.

[0044] 2. The EBT3 film for detecting radiation dose and measuring without washout of the present invention is more sensitive to the dose accuracy of CyberKnife. Once the dose of CyberKnife deviates, the EBT3 film for detecting radiation dose and measuring without washout can detect it quickly and effectively and make timely corrections, thereby ensuring the safety and effectiveness of treatment.

[0045] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0047] Figure 1 It is a flow chart of the CyberKnife dosage and mechanical accuracy integrated daily inspection method of the present invention;

[0048] Figure 2 A flow chart for establishing a target dose-grayscale curve diagram of CyberKnife for the present invention;

[0049] Figure 3 A flow chart for obtaining a dose distribution diagram of a verification plan of CyberKnife according to the present invention;

[0050] Figure 4 A flow chart of inserting the EBT3 film to be tested into the spherical square of the AQA phantom according to the present invention;

[0051] Figure 5A flowchart of obtaining the positioning error of the AQA phantom according to the present invention;

[0052] Figure 6 A flow chart of adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed according to the present invention;

[0053] Figure 7 The flowchart of the present invention for analyzing the dose diagram of EBT3 film. DETAILED DESCRIPTION

[0054] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0055] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0056] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0057] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0058] like Figures 1 to 7 As shown, an embodiment of the present invention provides a method for daily inspection of CyberKnife dose and mechanical accuracy, comprising the following steps:

[0059] Step S1, obtaining a verification plan dose distribution diagram of CyberKnife and a target dose-grayscale curve diagram of CyberKnife;

[0060] Step S2, inserting the radiation dose measurement process-free film (EBT3 film) to be tested into the spherical square of the automatic quality assurance deviation detection phantom (AQA phantom); specifically, compared with the film of the AQA phantom in the prior art, the EBT3 film has higher sensitivity and stability to the CyberKnife dose, thereby realizing the detection of the CyberKnife dose accuracy.

[0061] Step S3, obtaining the positioning error of the AQA phantom;

[0062] Step S4, adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom;

[0063] Step S5, irradiating the EBT3 film;

[0064] Step S6, scanning the irradiated EBT3 film to obtain a grayscale image of the EBT3 film; specifically, the EBT3 film should be kept away from light after being taken out of the AQA phantom, and scanned 24 hours after the EBT3 film is irradiated. The EBT3 film is placed in a direction where the short side of the EBT3 film is horizontal to the scanning direction of the scanner. The EBT3 film scanning parameters are resolution 72bpi, 48-bit true color, and no color correction.

[0065] Step S7, converting the grayscale image of the EBT3 film based on the target dose-grayscale curve to obtain the dose map of the EBT3 film; specifically, analyzing the dose map of the EBT3 film by film analysis software (such as film QA or RIT113, etc.), and converting the grayscale image of the EBT3 film into the dose map of the EBT3 film according to the target dose-grayscale curve.

[0066] Step S8: Perform image registration based on the dose map of the EBT3 film and the dose distribution map of the verification plan, analyze the dose map of the EBT3 film, and obtain the CyberKnife dose and mechanical accuracy.

[0067] The present invention first obtains the verification plan dose distribution diagram of CyberKnife and the target dose-grayscale curve diagram of CyberKnife, then inserts the washout-free EBT3 film to be tested for radiation dose measurement into the AQA phantom, and obtains the positioning error of the AQA phantom to adjust the position of the AQA phantom and the position of the five-dimensional treatment bed, thereby making the AQA phantom meet the mechanical accuracy requirements. Next, the EBT3 film is irradiated, and the irradiated EBT3 film is scanned to obtain a grayscale image of the EBT3 film, and the grayscale image of the EBT3 film is converted according to the target dose-grayscale curve diagram to obtain a dose map of the EBT3 film; then, image registration is performed based on the dose map of the EBT3 film and the verification plan dose distribution map, and it is determined that the dose map of the EBT3 film is spatially aligned with the verification plan dose distribution map, and then image registration is performed based on the dose map of the EBT3 film and the verification plan dose distribution map, and the dose map of the EBT3 film is analyzed to obtain the CyberKnife dose and mechanical accuracy, and detect the accuracy of the CyberKnife. The present invention can simultaneously realize the dose accuracy detection and mechanical accuracy detection of the CyberKnife, shorten the quality control time, and actually improve the daily inspection efficiency of the CyberKnife, thereby being able to increase the number of patients treated by the CyberKnife every day.

[0068] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 2 As shown, the target dose-grayscale curve diagram of CyberKnife includes the following steps:

[0069] Step S101, annotate the label information and dosage information of multiple target EBT3 films; specifically, annotate the label information and dosage information on each target EBT3 film to ensure that the irradiation dose of each target EBT3 film can be confirmed through the label information during subsequent processing and analysis.

[0070] Step S102, irradiate multiple target EBT3 films based on the dose information of each target EBT3 film; specifically, according to the dose information of each target EBT3 film, make the CyberKnife accelerator irradiate each target EBT3 film. In order to ensure the accuracy and uniformity of the CyberKnife dose, place the film in a water equivalent phantom with a layer thickness of 3 cm and a backscatter thickness of 5 cm, and irradiate the film. After irradiation, the film will self-develop different grayscales (target EBT3 films with different brightness). In addition, the irradiation conditions of each target EBT3 film are recorded in detail, including beam energy, irradiation time and equipment parameters.

[0071] Step S103, scan the target EBT3 film after irradiation to obtain multiple grayscale images; specifically, use a high-resolution scanner to scan multiple target EBT3 films, and ensure that the scanning resolution is set to 72 dpi, which can meet the requirements of the film analysis software (film QA or RIT113) for grayscale images. Select the transmission mode, use 24-bit true color scanning, and no color correction (to ensure sufficient grayscale levels to reflect dose changes and film dose deposition is not distorted). Then, fix the irradiated target EBT3 film on the scanner to avoid scratches or dust on the surface of the target EBT3 film, scan and save the scanned image. It should be noted that the method of scanning the irradiated EBT3 film is the same as the method of scanning the target EBT3 film after irradiation.

[0072] Step S104, based on the dose information and the plurality of grayscale images, a target dose-grayscale curve is established. Specifically, the corresponding target EBT3 film grayscale image is confirmed according to the dose information of each target EBT3 film, and a dose-grayscale curve is established using film analysis software (such as film QA or RIT113, etc.). It should be noted that polynomial fitting or exponential fitting is usually used to obtain a higher fitting accuracy, thereby establishing a dose-grayscale calibration curve. The target dose-grayscale curve can be used to convert the grayscale value of the unknown dose target EBT3 film into the actual CyberKnife dose, thereby verifying the accuracy of the radiotherapy plan.

[0073] Furthermore, before labeling the plurality of target EBT3 films with number information and dosage information, the method further includes: preparing the target EBT3 film, preparing a 5cm*5cm target EBT3 film.

[0074] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 2 As shown, after obtaining multiple grayscale images, the following steps are also included: Step S1031, performing noise and non-uniformity correction processing on the multiple grayscale images. Specifically, the grayscale images are corrected by image processing software (such as ImageJ or MATLAB, etc.).

[0075] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, a high-resolution scanner is used to scan the irradiated target EBT3 film, and the parameters use 16-bit grayscale.

[0076] Specifically, the high-resolution scanner used was Epson Perfection V700 / V800, and the parameters were 24-bit true color, 72 dpi resolution, and no color correction scanning conditions for film scanning to ensure sufficient gray levels to reflect dose changes and no distortion of film dose deposition.

[0077] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, the dose information of the plurality of target EBT3 films is 0.1Gy, 0.25Gy, 0.5Gy, 1Gy, 2Gy, 4Gy, 6Gy and 9Gy in sequence. The accelerator of the CyberKnife irradiates each of the target EBT3 films according to the metering information of 0.1Gy, 0.25Gy, 0.5Gy, 1Gy, 2Gy, 4Gy, 6Gy and 9Gy.

[0078] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 3 As shown, the method of obtaining the CyberKnife verification plan dose distribution map includes the following steps:

[0079] Step S1001, prepare a standard EBT3 film; specifically, the size of the standard EBT3 film is adapted to the AQA phantom, and the size of the standard EBT3 film is 6.23 cm*6.23 cm.

[0080] Step S1002, perform CT scanning on the standard EBT3 film to obtain a CT image; specifically, place the standard EBT3 film in the AQA phantom, and align the standard EBT3 film with the edge of the AQA phantom. Place it on the CT treatment bed according to the direction marked on the AQA phantom. Then, set the tube exposure parameters to: tube voltage 60kV, photocurrent 50mA, scanning layer thickness 1mm, perform CT scanning, and obtain a CT image. And import the CT image into the CyberKnife data management system.

[0081] Step S1003, set a spherical target area and a standard dose of the target area in the AQA phantom, perform low-resolution optimization and high-resolution calculation on the standard dose of the target area, and obtain the verification plan dose distribution diagram of the CyberKnife. Specifically, open the CyberKnife data management system and open the CT image. Enter the Contour workspace of the CyberKnife data management system, and set a spherical target area with a diameter of 25 mm in the AQA phantom. Then, enter the Align workspace, select Fiducial tracking, and mark all gold marks in the AQA phantom in the CyberKnife data management system. Then, enter the Plan workspace, select the IRIS collimator with a size of 25 mm. Then, set the standard dose of the target area, which can be 4Gy.

[0082] Next, use low resolution to optimize and generate the initial dose distribution. Then, enter the Evaluate workspace and use high resolution to calculate the dose and obtain the dose distribution map of the CyberKnife verification plan.

[0083] It should be noted that there is no particular order in which the verification plan dose distribution map of CyberKnife and the target dose-grayscale curve of CyberKnife are obtained. The verification plan dose distribution map of CyberKnife can be obtained first, or the target dose-grayscale curve of CyberKnife can be obtained first, or both can be performed at the same time.

[0084] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 4 The method of inserting the EBT3 film to be tested into the spherical square of the automatic quality assurance deviation detection body AQA phantom comprises the following steps:

[0085] Step S201, inserting the EBT3 film to be tested into the ball cube in the fixed water of the AQA phantom;

[0086] Step S202: Position the AQA phantom and adjust the position of the AQA phantom to ensure that the cross center line of the solid water surface coincides with the positioning laser light line.

[0087] Specifically, first insert the EBT3 film to be tested into the spherical cube of the AQA phantom, and then insert the spherical cube into the solid water of the AQA phantom, ensuring that the spherical cube is aligned with the solid water and the insertion direction is consistent. Next, turn on the positioning laser light of the CyberKnife and place the AQA phantom on the synchronous breathing quality control tool cart. Adjust the position of the AQA phantom to ensure that the cross center line of the solid water surface coincides with the positioning laser light line.

[0088] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 5As shown, the obtaining of the positioning error of the AQA phantom and adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom include the following steps:

[0089] Step S301, taking a first orthogonal image of the AQA phantom to obtain an AQA phantom positioning error;

[0090] Step S302: correcting the position of the five-dimensional treatment couch based on the AQA phantom positioning error.

[0091] Specifically, the X-ray tube emits a beam and takes the first orthogonal image of the AQA phantom to obtain the AQA phantom positioning error. The positioning error is automatically corrected by the five-dimensional treatment bed, so that the correction errors in the in-out, left-right, and lifting directions are less than 0.2 mm, and the errors in the pitch angle and tilt angle are less than 0.2°.

[0092] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 6 As shown, the obtaining of the positioning error of the AQA phantom and adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom also include the following steps:

[0093] Step S401, taking a second orthogonal image of the AQA phantom to obtain a horizontal plane rotation error of the first AQA phantom;

[0094] Step S402, correcting the position of the AQA phantom based on the horizontal plane rotation error of the first AQA phantom;

[0095] Step S403, taking a third orthogonal image of the AQA phantom to obtain a horizontal plane rotation error of the second AQA phantom;

[0096] Step S404: If the horizontal plane rotation error of the second AQA phantom meets the preset error, irradiating the EBT3 film.

[0097] Specifically, since the five-dimensional treatment bed cannot automatically correct the angle error in the horizontal direction, it is necessary to manually correct the angle in the horizontal direction of the five-dimensional treatment bed.

[0098] A second orthogonal image is taken of the AQA phantom to obtain the horizontal plane rotation error of the first AQA phantom; based on the horizontal plane rotation error of the first AQA phantom, the AQA phantom is manually rotated to correct the horizontal angle of the five-dimensional treatment bed.

[0099] Next, the AQA phantom is photographed for the third time in an orthogonal manner to obtain the horizontal plane rotation error of the second AQA phantom; when the horizontal plane rotation error of the second AQA phantom satisfies that the translation direction error is less than 2 mm and the angle rotation error is less than 2°, the EBT3 film is irradiated.

[0100] In addition, the tube voltage of the X-ray tube was set to 60Kv, the tube current was set to 60mA, and the exposure time was set to 50ms. Orthogonal X-ray images were taken, and the gold standard pair implanted in the AQA phantom was registered through digital reconstruction images and real-time imaging images, and the CyberKnife correction error was corrected to ±0.2mm in the translation direction and ±0.2° in the angle rotation. When the requirements were met, the high-voltage beam was emitted from the accelerator, and irradiation was performed in two directions at the CyberKnife frame angle of 0° and 90°.

[0101] In one embodiment of the CyberKnife dose and mechanical accuracy integrated daily inspection method of the present invention, Figure 7 As shown, the dose map based on the EBT3 film is image-aligned with the dose distribution map of the verification plan, and the dose map of the EBT3 film is analyzed to obtain the accuracy of the CyberKnife dose and the machine, including the following steps:

[0102] Step S801, image registration of the dose map of the EBT3 film and the dose distribution map of the verification plan; it should be noted that, although the positioning error of the AQA phantom is obtained in step S3, and the position of the AQA phantom and the position of the five-dimensional treatment bed are adjusted in step S4, the position of the AQA phantom still has an error after the above-mentioned manual adjustment or machine adjustment of the position of the AQA phantom and the five-dimensional treatment bed. Therefore, there is a certain position deviation between the dose map of the EBT3 film and the dose distribution map of the verification plan.

[0103] Step S802, analyzing the dose map of the EBT3 film after being aligned with the dose distribution map of the verification plan, and obtaining the position offset and dose deviation value of the CyberKnife; specifically, in this embodiment, the dose map of the EBT3 film after being aligned with the dose distribution map of the verification plan is analyzed by Gamma analysis through software such as Film QA or RIT113, and the position offset and dose deviation value of the CyberKnife can be obtained.

[0104] Step S803: Determine the CyberKnife dose and mechanical accuracy based on the CyberKnife position offset and dose deviation value.

[0105] Specifically, the evaluation criteria of the Gamma analysis method for detecting CyberKnife are that the dose deviation is less than 3% and the distance consistency tolerance is less than 2 mm.

[0106] If (dose information - CyberKnife target dose) / CyberKnife target dose is less than 3%, and the distance consistency deviation is greater than 2mm, then the CyberKnife metering dose accuracy is accurate, but the CyberKnife mechanical accuracy is inaccurate.

[0107] If (dose information - CyberKnife target dose) / CyberKnife target dose is less than 3%, and the distance consistency deviation is greater than 2mm, the CyberKnife metering dose accuracy is inaccurate, while the CyberKnife mechanical accuracy is accurate.

[0108] If (dose information - CyberKnife target dose) / CyberKnife target dose is greater than 3%, and the positioning error range distance consistency tolerance of the AQA phantom is greater than 2 mm, the CyberKnife metering dose accuracy and mechanical accuracy are both inaccurate.

[0109] Specifically, set the analysis parameters of the film analysis software (such as film QA or RIT113, etc.): grayscale threshold: 30%, dose deviation: 2%, distance deviation: 2mm, and use the film analysis software to analyze the gamma pass rate.

[0110] When the gamma pass rate is ≥90%, it means that (dose information-CyberKnife target dose) / CyberKnife target dose is less than 3%, and the distance consistency deviation is less than 2mm.

[0111] The present invention can simultaneously detect the dosage accuracy and mechanical accuracy of the CyberKnife, shorten the quality control time, and effectively improve the daily inspection efficiency of the CyberKnife, thereby increasing the number of patients treated by the CyberKnife every day. The CyberKnife dosage and mechanical accuracy integrated daily inspection method of the present invention is relatively simple, easy to operate, and effectively improves the quality of quality control.

[0112] Furthermore, the EBT3 film for detecting radiation dose and measuring without washout of the present invention is more sensitive to the dose accuracy of CyberKnife. Once the dose of CyberKnife deviates, the EBT3 film for detecting radiation dose and measuring without washout can detect it quickly and effectively and make timely corrections, thereby ensuring the safety and effectiveness of treatment.

[0113] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A method for daily inspection of CyberKnife dose and mechanical accuracy, characterized in that: The following steps are involved: Obtain the CyberKnife verification plan dose distribution diagram and CyberKnife target dose-grayscale curve diagram; Insert the EBT3 film to be tested for radiometric determination into the spherical square of the automatic quality assurance deviation detection body AQA phantom; Obtain the positioning error of the AQA phantom; Based on the positioning error of the AQA phantom, adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed; Irradiate the EBT3 film; Scan the irradiated EBT3 film to obtain a grayscale image of the EBT3 film; Converting the grayscale image of the EBT3 film based on the target dose-grayscale curve to obtain a dose image of the EBT3 film; Image registration was performed based on the dose map of the EBT3 film and the dose distribution map of the verification plan. The dose map of the EBT3 film was analyzed to obtain the accuracy of the CyberKnife dose and machinery.

2. The CyberKnife dose and mechanical accuracy integrated daily inspection method according to claim 1, characterized in that: The target dose-grayscale curve diagram of CyberKnife comprises the following steps: annotating number information and dose information on a plurality of target EBT3 films; irradiating a plurality of the target EBT3 films based on the dose information of each of the target EBT3 films; Scanning the irradiated target EBT3 film to obtain a plurality of grayscale images; A target dose-grayscale curve diagram is established based on the dose information and the plurality of grayscale images.

3. The CyberKnife dose and mechanical accuracy integrated daily inspection method according to claim 2, characterized in that: After obtaining a plurality of grayscale images, the method further includes the following steps: performing noise and non-uniformity correction processing on the plurality of grayscale images.

4. The CyberKnife dose and mechanical accuracy integrated daily inspection method according to claim 2, characterized in that: The irradiated target EBT3 film was scanned using a high-resolution scanner, with parameters of 48-bit true color, a resolution of 72 dpi, and no color correction.

5. The CyberKnife dose and mechanical accuracy integrated daily inspection method according to claim 2, characterized in that: The dose information of the multiple target EBT3 films is 0.1Gy, 0.25Gy, 0.5Gy, 1Gy, 2Gy, 4Gy, 6Gy and 9Gy respectively.

6. The CyberKnife dose and mechanical accuracy integrated daily inspection method according to claim 1, characterized in that: The method of obtaining the CyberKnife verification plan dose distribution map comprises the following steps: Prepare standard EBT3 film; Performing CT scanning on the standard EBT3 film to obtain a CT image; A spherical target area and a target area standard dose are set in the AQA phantom, and low-resolution optimization and high-resolution calculation are performed on the target area standard dose to obtain a verification plan dose distribution diagram of CyberKnife.

7. The CyberKnife dosage and mechanical accuracy integrated daily inspection method according to claim 1, characterized in that: The process of inserting the EBT3 film to be tested for radiation dosimetry into the spherical square of the automatic quality assurance deviation detection body AQA phantom comprises the following steps: Inserting the EBT3 film to be tested into the spherical cube located in the fixed water of the AQA phantom; The AQA phantom is positioned and adjusted to ensure that the cross center line of the solid water surface coincides with the positioning laser light line.

8. The CyberKnife dosage and mechanical accuracy integrated daily inspection method according to claim 1, characterized in that: The obtaining of the positioning error of the AQA phantom and adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom include the following steps: Taking a first orthogonal image of the AQA phantom to obtain a positioning error of the AQA phantom; The position of the five-dimensional treatment bed is corrected based on the AQA phantom positioning error.

9. The CyberKnife dosage and mechanical accuracy integrated daily inspection method according to claim 8, characterized in that: The obtaining of the positioning error of the AQA phantom and adjusting the position of the AQA phantom and the position of the five-dimensional treatment bed based on the positioning error of the AQA phantom also includes the following steps: Taking a second orthogonal image of the AQA phantom to obtain a horizontal plane rotation error of the first AQA phantom; Correcting the position of the AQA phantom based on the horizontal plane rotation error of the first AQA phantom; Taking a third orthogonal image of the AQA phantom to obtain a horizontal plane rotation error of the second AQA phantom; If the horizontal plane rotation error of the second AQA phantom meets the preset error, the EBT3 film is irradiated.

10. The CyberKnife dosage and mechanical accuracy integrated daily inspection method according to claim 1, characterized in that: The described method of performing image registration based on the EBT3 film dose map and the verification plan dose distribution map, analyzing the EBT3 film dose map, and obtaining the CyberKnife dose and mechanical accuracy includes the following steps: Perform image registration between the dose map of the EBT3 film and the dose distribution map of the verification plan; The dose map of the EBT3 film registered with the dose distribution map of the verification plan was analyzed to obtain the position offset and dose deviation value of the CyberKnife. The CyberKnife dose and mechanical accuracy are determined based on the CyberKnife position offset and dose deviation values.

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