A method for making an oral stent for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology

Abstract

The present application relates to the technical field of manufacturing oral stents for radiotherapy, and specifically discloses a method for manufacturing oral stents for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology, comprising manufacturing a non-individualized open-mouth stent by means of 3D printing technology; selecting a non-individualized open-mouth stent of corresponding size, placing it between the patient's upper and lower incisors and canines, and obtaining a CT image of the patient's open-mouth state; simulating a three-dimensional model of an individualized open-mouth stent according to the CT image of the patient's open-mouth state, and manufacturing the individualized open-mouth stent of the patient by means of 3D printing technology; having the patient wear the individualized open-mouth stent, obtaining a thin-layer image, outlining an irregular tongue depressor and a tongue periphery space filling model that fits the tongue surface area in the coronal plane, sphenoid plane, and cross-section of the thin-layer image, converting the tongue depressor and the tongue periphery space filling model into a first three-dimensional model, merging the individualized open-mouth stent three-dimensional model with the first three-dimensional model to obtain a merged model, and 3D printing an individualized oral stent.

Description

Technical Field

[0001] The present application relates to the technical field of manufacturing oral stents for radiotherapy, and specifically to a method for manufacturing oral stents for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology. Background Art

[0002] Tongue cancer is the most common malignant tumor in oral cancer, accounting for about 37% to 53% of oral squamous cell carcinoma. Radiotherapy is one of the main treatment methods for comprehensive treatment of tongue cancer patients. According to the CSCO guidelines, postoperative adjuvant radiotherapy is recommended for patients with T1-2N+ or T3-4 any N; for patients whose physical conditions do not allow, refuse surgery for various reasons, or whose tumor load is too large to be removed, radiotherapy alone is a radical treatment method. At present, patients with head and neck tumors mainly adopt the fixation mode of head and neck shoulder membrane to ensure that the patient's body position and the position of internal organs remain consistent during radiotherapy.

[0003] The tongue is an internal organ with a large range of motion. After being fixed on the surface of the head, shoulder and neck membrane, the tongue still has a large space for movement. Therefore, the main difficulty in radiotherapy for tongue cancer lies in the fixation of the tongue. If the tongue fixation effect is poor, during the radiotherapy process, the patient will make slight adjustments or movements due to swallowing or discomfort, and the high-dose radiation area may move to dangerous organs and normal tissues, such as the floor of the mouth, mandible, and sublingual gland. In this way, the radiation dose received by the tumor is not enough to achieve the treatment effect, resulting in an increased possibility of treatment failure or tumor recurrence. At the same time, it will also increase the risk of acute radiation damage to patients, such as stomatitis, dysphagia, loss of taste, and mandibular osteonecrosis. Therefore, in order to ensure the accuracy of radiotherapy for tongue cancer and minimize treatment-related side effects, it is particularly important to develop an effective radiotherapy oral stent.

[0004] In the prior art, the method of occlusal shaping is used to study and prepare individualized oral stents, but there is no unified standard for accurate tongue fixation for patients undergoing radiotherapy for tongue cancer. The problems mainly focus on the following aspects: (1) Insufficient filling: The individualized oral stents made by occlusal plasticity cannot be accurately filled, and the gaps in the front and lower parts of the tongue are large, resulting in a large space for the tongue to move during radiotherapy; (2) Poor comfort: The individualized oral stents made by occlusal plasticity are in an unnatural state because the tongue position is suppressed during occlusion, and the radiotherapy lasts for about 10 minutes, which makes it very easy for patients to feel uncomfortable. In summary, there is still a lack of effective solutions in the prior art for making individualized oral stents that meet the requirements of accurate radiotherapy for patients with tongue cancer. Summary of the invention

[0005] The purpose of this application is to provide a method for producing an oral stent for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology, so as to solve the problem in the prior art that there is still a lack of effective solutions for producing individualized oral stents that meet the precise radiotherapy requirements of tongue cancer patients.

[0006] To achieve the above-mentioned purpose, the embodiment of the present application provides a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology, comprising: manufacturing a non-individualized open stent by 3D printing technology;

[0007] According to the size of the patient's mouth opening, the non-individualized mouth opening bracket of the corresponding size is selected and placed between the patient's upper and lower incisors and canines, and a CT image of the patient's mouth opening state is obtained through CT tomography;

[0008] According to the CT image of the patient's open state, a three-dimensional model of an individualized open stent is simulated, and based on the three-dimensional model of the individualized open stent, an individualized open stent of the patient is manufactured by 3D printing technology;

[0009] The patient is made to wear the personalized oral bracket, and then a CT scan is performed to obtain a thin-layer image. An irregular tongue depressor and a tongue periphery space filling model that fit the tongue surface area are outlined in the coronal plane, lateral plane, and cross-sectional plane of the thin-layer image. The tongue depressor and the tongue periphery space filling model are converted into a first three-dimensional model, and the personalized oral bracket three-dimensional model and the first three-dimensional model are merged to obtain a merged model. Based on the merged model, a personalized oral bracket is 3D printed.

[0010] Optionally, the non-individualized open stent is made of polylactic acid material;

[0011] The non-individualized open stent is in the shape of an elongated strip.

[0012] Optionally, the non-individualized open stent has multiple sizes, and the sizes of the non-individualized open stents of different sizes include: length 10mm-20mm, height 20mm-35mm, width 30mm-50mm.

[0013] Optionally, the non-individualized opening bracket of a corresponding size is selected according to the size of the patient's opening mouth, and is placed between the patient's upper and lower incisors and canines, specifically including:

[0014] The midline of the non-individualized open bracket is made to coincide with the midline of the central incisors on both sides of the patient.

[0015] Optionally, simulating a three-dimensional model of an individualized open stent according to the CT image of the patient's open state specifically includes:

[0016] According to the CT image of the patient's opening state, the opening state is simulated by 3D simulation to simulate the individualized opening stent three-dimensional model.

[0017] Optionally, after obtaining the thin layer image, the method further comprises:

[0018] Based on the thin layer image, a second three-dimensional model including the patient's bones, upper and lower teeth, tongue, body skin and oral cavity is established, and the upper dental support and lower dental pad are outlined according to the length and width of the patient's upper and lower dental arches, and the upper and lower dental alveoli in the second three-dimensional model are subtracted using a Boolean operation module.

[0019] Optionally, after obtaining the merged model, the method further includes:

[0020] The merged model is placed in the second three-dimensional model to check whether the gap fillings on the upper tongue, in front of the tongue, and under the tip of the tongue are effectively filled and gap-free. If so, the merged model is saved as a Binary STL format file, and the file is input into a 3D printer to print out the individualized oral bracket.

[0021] Optionally, the thin layer image is in Dicom format, with a layer thickness of 1.5 mm and a layer spacing of 1.5 mm.

[0022] The embodiments of the present application have the following advantages:

[0023] Compared with the prior art, the above technical solution provides a method for making an oral stent for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology. In each step of production, fine adjustment of the stent can more effectively prepare an individualized oral stent. This oral stent has a high degree of fit with the tongue surface and the gap around the tongue, which can minimize the mobility of the tongue, increase the repeatability of the tongue position during radiotherapy, and improve the efficacy of precision radiotherapy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings described below are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0025] Figure 1 A flowchart of a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided in at least one embodiment of the present application;

[0026] Figure 2A schematic diagram of a non-individualized open stent for a method of manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided in at least one embodiment of the present application;

[0027] Figure 3 A schematic diagram of obtaining a CT image of a patient's open mouth state in a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application;

[0028] Figure 4 A schematic diagram of a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided in at least one embodiment of the present application, simulating an opening state by 3D simulation to simulate a three-dimensional model of an individualized opening stent;

[0029] Figure 5 A schematic diagram of an individualized open stent according to a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided in at least one embodiment of the present application;

[0030] Figure 6 A schematic diagram of a patient CT image simulating an individualized open stent according to a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application;

[0031] Figure 7 A schematic diagram of a combined model for obtaining a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application;

[0032] Figure 8 A schematic diagram of a CT image of a patient wearing a personalized oral stent according to a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application;

[0033] Fig. 9 A schematic diagram of an individualized oral stent according to a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided in at least one embodiment of the present application;

[0034] Fig.10 A schematic diagram of the coverage effect of the space around the tongue on a tongue cancer patient wearing an individualized oral stent, provided by at least one embodiment of the present application, in a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology;

[0035] Fig.11A method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application is provided, and a target area delineation diagram of a tongue cancer patient after wearing a personalized oral stent;

[0036] Fig.12 A target dose volume map of a tongue cancer patient after wearing a personalized oral stent, provided by at least one embodiment of the present application, in a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology;

[0037] Fig.13 A schematic diagram of a blood routine report of a tongue cancer patient wearing a personalized oral stent during radiotherapy, according to a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application;

[0038] Fig.14 A schematic diagram of a report on liver and kidney function of a tongue cancer patient wearing a personalized oral stent during radiotherapy, according to a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology provided by at least one embodiment of the present application. DETAILED DESCRIPTION

[0039] The following is a description of the implementation of the present application by specific specific embodiments. People familiar with the technology can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0040] In the description of the present application, it should be noted that the terms "first", "second" and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0041] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0042] The present application embodiment provides a method for manufacturing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology, referring to Figure 1 , including the steps of:

[0043] In step 101, a non-individualized open stent for a tongue cancer patient is manufactured by 3D printing technology.

[0044] In some embodiments, the non-individualized open stent is made of polylactic acid (PLA) material.

[0045] In some embodiments, the non-individualized open stent is in the shape of an elongated strip.

[0046] In some embodiments, the non-individualized open stent has multiple sizes, and the sizes of different sizes of non-individualized open stents include: length 10mm-20mm, height 20mm-35mm, width 30mm-50mm. Figure 2 .

[0047] At step 102, according to the size of the patient's mouth opening, a non-individualized mouth opening bracket of corresponding size and comfortable mouth opening is selected from a plurality of non-individualized mouth opening brackets of different sizes, and is placed between the patient's upper and lower incisors and canines. A CT image of the patient's mouth opening state is obtained through CT tomography.

[0048] In some embodiments, the non-individualized opening bracket of a corresponding size is selected according to the size of the patient's opening, and is placed between the patient's upper and lower incisors and canines, specifically including:

[0049] The midline of the non-individualized mouth opening bracket is made to coincide with the midline of the central incisors on both sides of the patient. The patient lies on his back on the spiral CT examination bed, with his hands hanging down and naturally relaxed on both sides of the body, and his tongue in a naturally relaxed state. Swallowing is prohibited. A CT tomography scan with a layer thickness of 1 mm is performed to obtain a CT image of the patient's mouth opening state. Obtaining a CT image of the patient's mouth opening state reference Figure 3 .

[0050] At step 103, a three-dimensional model of an individualized open-mouth bracket is simulated based on the CT image of the patient's open-mouth state, and a 3D printing device (MTDST-STD) is used to make the individualized open-mouth bracket of the patient based on the three-dimensional model of the individualized open-mouth bracket through 3D printing technology using polylactic acid (PLA) material. The bracket can completely match the position of the upper and lower teeth in the open-mouth state of the patient. When the patient wears the mold to scan the CT, the mold does not press the tongue, and the tongue is in a relaxed state. Figure 4 In order to simulate the opening state through 3D simulation, a schematic diagram of the three-dimensional model of the individualized open stent is simulated. Figure 5 Schematic diagram of individualized open stent. Figure 6 Schematic diagram of a patient's CT image simulating an individualized open stent.

[0051] In some embodiments, simulating a three-dimensional model of an individualized open stent according to the CT image of the patient's open state specifically includes:

[0052] According to the CT image of the patient's opening state, the opening state is simulated by 3D simulation to simulate the individualized opening stent three-dimensional model.

[0053] At step 104, the patient lies on his back with his hands on both sides of the body, and relaxes. The patient wears the individualized mouth opening bracket, keeps his mouth open, and his tongue is in a relaxed position. Swallowing is prohibited. A CT scan is then performed to obtain the spiral CT device scanning data with a 1.5 mm layer thickness and a thin layer image (Dicom format) with a 1.5 mm layer spacing for standby use. An irregular tongue depressor and a tongue surrounding space filling model that fit the tongue surface area are outlined in the coronal plane, lateral plane, and cross-sectional plane of the thin layer image, and then the tongue depressor and the tongue surrounding space filling model are converted into a first three-dimensional model. Finally, the individualized mouth opening bracket three-dimensional model and the first three-dimensional model (upper and lower dental trays, tongue depressor, and tongue surrounding space filling model) are merged to obtain a merged model. Based on the merged model, a personalized oral bracket is 3D printed for personalized auxiliary radiotherapy tongue fixation. Reference Figure 7 and Figure 8 , Figure 7 To obtain a schematic diagram of the merged model, Figure 8 Schematic diagram of a CT image of a patient wearing a personalized oral brace. Schematic diagram of a 3D printed personalized oral brace for reference Fig. 9 .

[0054] In some embodiments, after acquiring the thin layer image, the method further comprises:

[0055] The thin slice image is imported into 3Dslicer software, and a second three-dimensional model including the patient's bones, upper and lower teeth, tongue, body surface skin and oral cavity is established based on the thin slice image, and the upper dental tray and lower dental pad are outlined according to the length and width of the patient's upper and lower dental arches, and the upper and lower dental alveoli in the second three-dimensional model are subtracted using the Boolean operation module. Ensure that the dental tray, pad and teeth are fixed and cannot move.

[0056] In some embodiments, after obtaining the merged model, the method further includes:

[0057] The merged model is placed in the second three-dimensional model to check whether the gap fillings on the upper tongue, in front of the tongue, and under the tip of the tongue are effectively filled and gap-free. If so, the merged model is saved as a Binary STL format file, and the file is input into a 3D printer to print out the individualized oral bracket.

[0058] Specifically, the merged model can be placed in the second three-dimensional model and converted into a two-dimensional image, and then the gap fillings of the upper tongue, the front of the tongue, and under the tip of the tongue can be checked layer by layer to see whether they are effectively filled and have no gaps.

[0059] In some embodiments, the steps of wearing a personalized oral brace for a tongue cancer patient for position fixation and CT scanning include:

[0060] The patient was placed in a supine position, wearing an individualized oral brace fixed with a head, neck and shoulder mask. Positioning was performed on a large-aperture 4-row CT simulator produced by GE, and three cross marks were made on the mask with a 3D laser light, with metal dot marks attached. Then a CT scan was performed, with a layer thickness of 3 mm and a layer spacing of 3 mm. The scanning range was from the skull base to the supraclavicular fossa, and the image data was transmitted to the Monaco radiotherapy planning system via a local area network.

[0061] In some embodiments, the steps of target delineation, plan formulation, and plan quality assessment include:

[0062] Combined with the patient's CT positioning images, head and neck MRI images, pathology reports and other information, and referring to the International Commission of Radiological Units (ICUR) reports No. 50, No. 62, and No. 83, the gross target volume (GTV), clinical target volume (CTV), planned target volume (PTV) and organs at risk (OARs) are outlined on the Monaco radiotherapy planning system. A specific plan is formulated based on the actual clinical situation. The dosimetric results of the radiotherapy plan are evaluated by isodose curve distribution and dose volume histogram.

[0063] In some embodiments, the step of evaluating the efficacy and complications of radiotherapy includes:

[0064] Blood routine and liver and kidney function were checked before radiotherapy, weekly during radiotherapy, and after radiotherapy. The severity of oral complications was observed and recorded (using CTCAE V4.0). The radiotherapy results were evaluated according to the criteria for evaluating the efficacy of solid tumors (using RECIST).

[0065] In summary, compared with the prior art, the above technical solution provides a method for making an oral stent for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology. In each step of production, fine adjustment of the stent can more effectively prepare an individualized oral stent. This oral stent has a high degree of fit with the tongue surface and the gap around the tongue, which can minimize the mobility of the tongue, increase the repeatability of the tongue position during radiotherapy, and improve the efficacy of precision radiotherapy.

[0066] This personalized oral bracket has a high degree of fit with the tongue surface and the space around the tongue, and can effectively fill the space around the tongue (reference Fig.10 ), significantly reducing the range of tongue movement, while improving tongue fixation and patient comfort.

[0067] After using the individualized oral stent provided in this application, the dose distribution in the target area is uniform, and there are no obvious cold spots and hot spots near the stent (reference Fig.11 ), the dose to the organ at risk is within the prescribed dose limit safety range (reference Fig.12 ), meet the corresponding standards and improve the efficacy of precision radiotherapy.

[0068] refer to Fig.13 and Fig.14 According to the diagram of tolerable toxic and side effects during radiotherapy, patients can wear the personalized oral stent throughout the radiotherapy.

[0069] Note that, unless otherwise directly stated, all features disclosed in this specification (including any attached claims, abstracts and drawings) may be replaced by alternative features for achieving the same, equivalent or similar purposes. Therefore, unless otherwise explicitly stated, each feature disclosed is only an example of a group of equivalent or similar features. Where used, further, preferably, further and more preferably are simple beginnings for elaborating another embodiment based on the aforementioned embodiment, and the content of further, preferably, further or more preferably followed by the aforementioned embodiment is combined with the complete composition of another embodiment. Several further, preferably, further or more preferably settings following the same embodiment can be arbitrarily combined to form another embodiment.

[0070] In the implementation of functions and steps, the corresponding functions and steps in various embodiments may also occur in a different order than shown. For example, two consecutive functions and steps may actually be performed or implemented substantially in parallel, and they may sometimes be performed or implemented in the opposite order, depending on the functions involved.

[0071] Although the present application has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made to the present application. Therefore, these modifications or improvements made without departing from the spirit of the present application all fall within the scope of protection claimed in the present application.

Claims

1. A method for producing an oral stent for radiotherapy based on three-dimensional imaging data of tongue cancer patients and 3D printing technology, characterized in that: include: Non-individualized open stents were produced by 3D printing technology; According to the size of the patient's mouth opening, the non-individualized mouth opening bracket of the corresponding size is selected and placed between the patient's upper and lower incisors and canines, and a CT image of the patient's mouth opening state is obtained through CT tomography; According to the CT image of the patient's open state, a three-dimensional model of an individualized open stent is simulated, and based on the three-dimensional model of the individualized open stent, an individualized open stent of the patient is manufactured by 3D printing technology; The patient is made to wear the personalized oral bracket, and then a CT scan is performed to obtain a thin-layer image. An irregular tongue depressor and a tongue periphery space filling model that fit the tongue surface area are outlined in the coronal plane, lateral plane, and cross-sectional plane of the thin-layer image. The tongue depressor and the tongue periphery space filling model are converted into a first three-dimensional model, and the personalized oral bracket three-dimensional model and the first three-dimensional model are merged to obtain a merged model. Based on the merged model, a personalized oral bracket is 3D printed.

2. The method for producing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology according to claim 1, characterized in that: Using polylactic acid material to make the non-individualized open stent; The non-individualized open stent is in the shape of an elongated strip.

3. The method for producing an oral stent for radiotherapy based on three-dimensional image data of a tongue cancer patient and 3D printing technology according to claim 1, characterized in that: The non-individualized open stent has multiple sizes, and the sizes of different sizes of non-individualized open stents include: length 10mm-20mm, height 20mm-35mm, width 30mm-50mm.

4. The method for producing an oral stent for radiotherapy based on three-dimensional image data of a tongue cancer patient and 3D printing technology according to claim 1, characterized in that: The non-individualized opening bracket of a corresponding size is selected according to the size of the patient's opening, and is placed between the patient's upper and lower incisors and canines, specifically including: The midline of the non-individualized open bracket is made to coincide with the midline of the central incisors on both sides of the patient.

5. The method for producing an oral stent for radiotherapy based on three-dimensional image data of a tongue cancer patient and 3D printing technology according to claim 1, characterized in that: The method of simulating a three-dimensional model of an individualized open stent according to the CT image of the patient's open state specifically includes: According to the CT image of the patient's opening state, the opening state is simulated by 3D simulation to simulate the individualized opening stent three-dimensional model.

6. The method for producing an oral stent for radiotherapy based on three-dimensional imaging data of a tongue cancer patient and 3D printing technology according to claim 1, characterized in that: After obtaining the thin layer image, the method further includes: Based on the thin layer image, a second three-dimensional model including the patient's bones, upper and lower teeth, tongue, body skin and oral cavity is established, and the upper dental support and lower dental pad are outlined according to the length and width of the patient's upper and lower dental arches, and the upper and lower dental alveoli in the second three-dimensional model are subtracted using a Boolean operation module.

7. The method for producing an oral stent for radiotherapy based on three-dimensional image data of a tongue cancer patient and 3D printing technology according to claim 6, characterized in that: After obtaining the merged model, the method further includes: The merged model is placed in the second three-dimensional model to check whether the gap fillings on the upper tongue, in front of the tongue, and under the tip of the tongue are effectively filled and gap-free. If so, the merged model is saved as a Binary STL format file, and the file is input into a 3D printer to print out the individualized oral bracket.

8. The method for producing an oral stent for radiotherapy based on three-dimensional image data of a tongue cancer patient and 3D printing technology according to claim 1, characterized in that: The thin layer images are in Dicom format, with a layer thickness of 1.5 mm and a layer spacing of 1.5 mm.

Images