Universal labyrinth source applicator and method for realizing multi-angle accurate planting thereof
Through a universal tortuous applicator and a multi-angle implantation method guided by mathematical models, the problems of difficulty and high cost of implantation in radiotherapy for cervical cancer have been solved, precise implantation and efficient coverage of the tumor area have been achieved, and the treatment effect and safety have been improved.
Patent Information
- Application Number
- CN202510938781.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-08
- Publication Date
- 2025-10-03
AI Technical Summary
In the existing radiotherapy for cervical cancer, traditional implantation technology has problems such as difficulty in implantation, insufficient individual adaptation, high economic cost, and poor accuracy and repeatability. In particular, manual implantation and 3D printed mold-guided implantation are blind and experience-dependent, which affects the treatment effect.
A universal tortuous path applicator is used. By setting the function and mathematical model of the implant needle channel and combining it with CT scan image data, the implant needle's implant path and depth are calculated to achieve precise implantation at multiple angles, ensuring that the radiation source accurately covers the tumor area.
It improves the accuracy and efficiency of cervical cancer radiotherapy, reduces radiation damage to normal tissues, reduces treatment costs, and improves treatment effects.
Smart Images
Figure CN120733277A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of medical device applications, and in particular to a universal maze applicator and a method for achieving multi-angle precise implantation thereof. Background Art
[0002] Cervical cancer is the most common gynecological malignancy, primarily treated with surgery, radiotherapy, and chemotherapy. Radiotherapy, a localized treatment method that uses radiation to treat tumors, can be divided into external beam radiation therapy and brachytherapy. Brachytherapy, also known as internal radiation therapy, involves placing an applicator near the tumor area and then controlling the afterloader to deliver the radiation source into the applicator. Brachytherapy for cervical cancer is an indispensable step in ensuring effective treatment. Brachytherapy primarily targets the primary lesion and adjacent invasive areas, and different vaginal applicators can be selected based on specific circumstances. Traditional intrauterine tube applicators provide insufficient dose coverage for locally advanced cervical cancer. By inserting an implant needle directly into the tumor or high-risk area through the vagina, the dose distribution is significantly more conformal and hot and cold spots are reduced. Radiation damage to organs at risk, such as the bladder and rectum, is a major complication of radiotherapy for cervical cancer, and thus radiation exposure can be reduced accordingly. At present, the most commonly used implantation techniques in cervical cancer surgery are: first, manual implantation with the help of some auxiliary instruments. Clinically, it is usually performed by doctors based on experience according to the location, size and shape of the tumor. Moreover, three-dimensional intertissue implantation and close-range treatment is not completed in one go. It is usually treated multiple times based on multiple factors such as tumor size, invasion depth and the dose to surrounding normal tissues. Manual implantation under CT guidance is difficult to guarantee the accuracy and repeatability of each implantation, and has high requirements for the doctor's treatment experience and skills. The operation is difficult, with obvious blindness and experience dependence. It has strong subjectivity, long operation time and insufficient individual adaptation, and ultimately affects the scope of radiotherapy. Second, 3D printed mold-guided implantation can reduce the difficulty of implantation to a certain extent, but its economic cost is high, its versatility is not strong, and it is difficult to promote and apply. Moreover, after the instrument is formulated, the direction and position of the implantation needle cannot be adjusted in time during the treatment process. Summary of the Invention
[0003] The present invention provides a universal maze-type applicator and a method for achieving multi-angle precise implantation thereof, in order to solve the problems existing in the above background.
[0004] In order to achieve the above object, the present invention adopts the following technical solutions:
[0005] A universal maze applicator comprises a cylinder, a uterine cavity channel is opened at the center of the axis of the cylinder, a plurality of insertion needle channels are opened through the cylinder located on the outer edge of the uterine cavity channel, an insertion inlet is set at the intersection of the insertion needle channel and the top surface of the cylinder, and an insertion outlet is set at the intersection of the insertion needle channel and the bottom surface of the cylinder.
[0006] Furthermore, a method for achieving multi-angle precision implantation using a universal maze applicator is also provided, comprising the following steps:
[0007] Step 1: Set the function of the applicator needle channel to be f(x)-(xa) -k , k>0, according to the mathematical model, the tangent function at the implantation outlet is q(x)-k(xa)+k+1, where -k is the tangent slope, a is the diameter ratio of the cylinder, and the tangent function is obtained. Right now Then by The vertical distance x from the tumor target to the uterine cavity is obtained, which is the horizontal insertion range of the insertion needle, where L3 is the length of the insertion needle entering the patient's tumor, Δ x To increase the radial treatment range and adjust the k value, a tortuous implant applicator with multiple implant needle channels can be obtained.
[0008] Step 2: Select the labyrinthine insertion applicator suitable for implantation obtained in step 1 according to the k value and the location of the tumor target. First, insert the uterine tube into the patient's uterus. Then, put the labyrinthine applicator on the uterine tube and push it into the appropriate position of the patient's vagina. After the bottom of the labyrinthine applicator reaches the cervix, fix the uterine tube on the labyrinthine applicator through a fixing nut. Preset the labyrinthine applicator in a mathematical coordinate system. Fix the labyrinthine applicator on the treatment bed and perform a CT scan to obtain imaging data of the patient's uterus.
[0009] Step 3. Based on the position and size of the tumor shown in the image, measure the vertical distance x from the needle tip to the uterine cavity in the CT image and record the image layer number p from the tumor target to the bottom of the cylindrical applicator. According to the coordinate system area, the direction, angle and depth of the implant needle into the patient's body are obtained, and the required implant entrance of the implant needle is determined. Then, a matching implant needle channel is selected for implantation. The total length of the implant needle is preset to a fixed value L, L=L1+L2+L3, L1 is the remaining length of the implant needle outside the patient's body, which can be measured during the implantation process, L2 is the tortuous length of the implant needle inside the tortuous implant applicator, and the integral calculation is h+0.2cm, h is the height of the tortuous implant applicator, and L3 is the length of the implant needle entering the patient's tumor. During the implantation process, the length of L1 is observed and its length is actually measured.
[0010] Step 4: Based on the CT scan layer thickness of 0.1cm-0.5cm in step 3, the distance from the tumor target to the lower surface of the applicator is Δ y =(0.1-0.5)p, then through Right now Calculate the depth L3 that the implant needle needs to enter the patient's tumor, and then obtain L1 = L-L2-L3. Finally, compare the theoretical calculated value L1 of the implant needle entering the patient's tumor with the length L1 of the implant needle remaining outside the patient's body measured in step 3 to obtain the implant depth of the implant needle accurately inserted into the tumor target during the implantation process.
[0011] Step 5: Finally, the CT device scans the image again, inserts the pointed flexible implant needle into the matching implant needle channel, and removes the needle core to ensure that the implant needle channel is hollow. Then, the after-loading radiation source is used to perform close-range precision radiotherapy on the tumor target.
[0012] The present invention has the following beneficial effects:
[0013] The present invention provides a universal tortuous applicator and a method for achieving multi-angle precise implantation thereof. The implantation path of the implant needle of the applicator is determined by a function, and then the applicator is placed in a mathematical coordinate system. The vertical distance from the tumor target to the uterine canal, that is, the lateral implantation range of the implantation needle, is calculated through the scanning image data of the CT device. Then, the depth to which the implantation needle needs to enter the patient's tumor is theoretically calculated by the number of image layers from the tumor target to the lower surface of the applicator. At the same time, after predicting the required implantation needle channel, the appropriate implantation needle channel of the tortuous implant applicator is selected for implantation. By comparing the theoretical value with the actual length of the remaining implant needle exposed outside the patient's body after implantation, the precise implantation depth of the implant needle in the tumor target area can be obtained, so that during the afterloading treatment of the tumor, the radiation source can accurately cover the treatment area of the tumor lesion, which greatly improves the overall treatment effect of cervical cancer and solves the current problem of insufficient dose coverage of the lesion, greater radiation damage to the patient's organs and high treatment costs due to the common use of manual implantation or printed mold guidance in radiotherapy of cervical cancer. Ultimately, it affects the effect of radiotherapy for cervical cancer. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a three-dimensional schematic diagram of the overall arrangement of the implant needle channel of the universal labyrinth applicator in the present invention.
[0015] Figure 2 This is a forward schematic diagram of the overall arrangement of the implant needle channel of the universal labyrinth applicator in the present invention.
[0016] Figure 3 Schematic diagram of the universal maze applicator of the present invention for implementing multi-angle precise implantation.
[0017] The meanings of the reference numerals are as follows:
[0018] 1. Cylinder; 2. Uterine canal channel; 3. Implantation needle channel; 4. Fixing nut; 5. Implantation inlet; 6. Implantation outlet; 7. Tumor target site. DETAILED DESCRIPTION
[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0020] like Figure 1-2 As shown, a universal maze applicator comprises a cylinder 1, a uterine cavity channel 2 is provided at the center of the axis of the cylinder 1, a plurality of insertion needle channels 3 are provided through the cylinder 1 on the outer edge of the uterine cavity channel 2, an insertion inlet 5 is provided at the intersection of the insertion needle channel 3 and the top surface of the cylinder 1, and an insertion outlet 6 is provided at the intersection of the insertion needle channel 3 and the bottom surface of the cylinder 1.
[0021] The process of achieving multi-angle precision implantation with a universal maze applicator includes the following steps:
[0022] Step 1: Set the function of the applicator needle channel 3 to be f(x) = (xa) -k , k>0, according to the mathematical model, the tangent function at the implantation outlet 6 is q(x)=-k(xa)+k+1, where -k is the tangent slope, a is the diameter ratio of the cylinder 1, and the tangent function is obtained Right now Then by The vertical distance x from the tumor target 7 to the uterine cavity is obtained, which is the horizontal insertion range of the insertion needle, where L3 is the length of the insertion needle entering the patient's tumor, Δ x In order to increase the radial treatment range and adjust the k value, a tortuous implant applicator with multiple implant needle channels 3 can be obtained.
[0023] Step 2: Select the labyrinthine insertion applicator suitable for implantation obtained in step 1 according to the k value and the position of the tumor target 7. First, insert the uterine tube into the patient's uterus. Then, put the labyrinthine applicator on the uterine tube and push it into the appropriate position of the patient's vagina. After the bottom of the labyrinthine applicator reaches the cervix, fix the uterine tube on the labyrinthine applicator through the fixing nut 4. Preset the labyrinthine applicator in a mathematical coordinate system. After fixing the labyrinthine applicator on the treatment bed, perform a CT scan to obtain imaging data of the patient's uterus.
[0024] Step 3. According to the position and size of the tumor shown in the image, measure the vertical distance x from the needle tip to the uterine cavity in the CT image and record the image layer number p from the tumor target position 7 to the bottom surface of the applicator cylinder 1. According to the coordinate system area, the direction, angle and depth of the implant needle into the patient's body are obtained, and the implant inlet 5 required by the implant needle is determined. Then, the matching implant needle channel 3 is selected for implantation. The total length of the implant needle is preset to a fixed value L, L=L1+L2+L3, L1 is the remaining length of the implant needle outside the patient's body, which can be measured during the implantation process, L2 is the tortuous length of the implant needle inside the tortuous implant applicator, and the integral calculation is h+0.2cm, h is the height of the tortuous implant applicator, and L3 is the length of the implant needle entering the patient's tumor. During the implantation process, the length of L1 is observed and its length is actually measured.
[0025] Step 4: Based on the CT scanning layer thickness of 0.1cm-0.5cm in step 3, the values can be 0.1cm, 0.2cm, 0.3cm, 0.4cm and 0.5cm, etc., then the distance from the tumor target 7 to the lower surface of the applicator is Δ y =(0.1-0.5)p, then through Right now Calculate the depth L3 that the implant needle needs to enter the patient's tumor, then obtain L1 = L-L2-L3, and finally compare the theoretical calculated value L1 of the implant needle entering the patient's tumor with the length L1 of the implant needle remaining outside the patient's body measured in step 3 to obtain the implant depth of the implant needle accurately inserted into the tumor target site 7 during the implantation process.
[0026] Step 5: Finally, the CT device scans the image again, inserts the pointed flexible implant needle into the matching implant needle channel 3, and then removes the needle core to ensure that the implant needle channel 3 is hollow. Then, the after-loading radiation source is used to perform close-range precision radiotherapy on the tumor target 7.
[0027] Furthermore, the present invention is further described through specific examples.
[0028] The general function of the curve of the implant needle channel in the maze implant applicator is f(x) = (xa) -k , (k>0, -1<a<1, 0<x<1+a), then The slope of the tangent line is -k, such as Figure 3 As shown, m and n are the upper and lower boundaries of the applicator, and the intersection points of each implantation needle curve and the n surface are A, B, C, etc. The distance between mn is the length h of the applicator cylinder 1, and the curve f 22 、f 52 、f 10At the intersection point C (1+a, 1) with the bottom surface of cylinder 1, the tangent function of the curve is q(x)=-k(xa)+k+1. The following function (curve function and its tangent at the intersection point) is used as an example:
[0029] q 22 =x -2 , (0<x<1), q 22 = -2x + 2 + 1, (x ≥ 1);
[0030] f 52 =x -5 , (0<x<1), q 52 =-5x+5+1, (x≥1);
[0031] f 10 =x -10 , (0<x<1), q 10 = -10x + 10 + 1, (x ≥ 1);
[0032] f 51 =(x-0.5) -5 , (0<x<1.5), a=0.5;
[0033] q 51 =-5(x-0.5)+5+1, x≥1.5;
[0034] f 53 =(x+0.5) -5 , (0<x<0.5), a=-0.5;
[0035] q 53 =-5(x+0.5)+5+1, x≥0.5;
[0036] The figure shows that the smaller the k value, the larger the treatment range that the implant needle can treat after passing through the implant needle channel 3. The specific treatment range can be calculated based on the function and known conditions. As the k value is adjusted, a series of tortuous implant applicators with multiple implant needle channels of different tortuous diameters can be obtained.
[0037] That is, function f 51 =(x-0.5) -5 , (0<x≤1.5), a=0.5, 4cm diameter cylindrical curved implant source, distance from point A to the central axis is 1.5cm, coordinates (1.5,1), tangent q 51=-5(x-0.5)+5+1, x≥1.5, k=5, the total length of the implant needle is 20cm, h=10cm, assuming that the length of the top of the implant needle extending from the applicator is 5cm, then L3=5cm, x=2.48cm, Δx=0.98cm, so it can be seen that the treatment range x can be obtained according to the length of the top of the implant needle extending from the applicator, that is, the vertical distance from the tip of the implant needle to the central axis of the applicator, and compared with the same side, the treatment range is expanded by 0.98cm than the parallel implant needle channel 3 of the applicator.
Claims
1. A universal labyrinth applicator, characterized by: The invention comprises a cylinder (1), a uterine cavity canal channel (2) is provided at the center of the axis of the cylinder (1), a plurality of insertion needle channels (3) are provided through the cylinder (1) located on the outer edge of the uterine cavity canal channel (2), an insertion inlet (5) is provided at the intersection of the insertion needle channel (3) and the top surface of the cylinder (1), and an insertion outlet (6) is provided at the intersection of the insertion needle channel (3) and the bottom surface of the cylinder (1).
2. The universal labyrinth applicator according to claim 1, further comprising a method for achieving multi-angle precision implantation using the universal labyrinth applicator, characterized in that: The following steps are involved: Step 1: Set the function of the applicator needle channel (3) to be f(x)-(xa) -k , k>0, according to the mathematical model, the tangent function at the implantation outlet (6) is q(x)=-k(xa)+k+1, where -k is the tangent slope, a is the diameter ratio of the cylinder (1), and the tangent function is obtained Right now Then by The vertical distance x from the tumor target (7) to the uterine cavity is obtained, which is the horizontal insertion range of the insertion needle, where L3 is the length of the insertion needle entering the patient's tumor, Δ x In order to increase the radial treatment range and adjust the k value, a tortuous implant source device with multiple implant needle channels (3) can be obtained; Step 2: Select the labyrinthine insertion applicator suitable for implantation obtained in step 1 according to the k value and the position of the tumor target (7), first insert the uterine cavity tube into the patient's uterus, then put the labyrinthine applicator on the uterine cavity tube and push it into the appropriate position of the patient's vagina, after the bottom of the labyrinthine applicator reaches the cervix, fix the uterine cavity tube on the labyrinthine applicator through the fixing nut (4), preset the labyrinthine applicator in a mathematical coordinate system, and fix the labyrinthine applicator on the treatment bed and perform CT scanning to obtain imaging data of the patient's uterus; Step 3. Based on the tumor position and size shown in the image, measure the vertical distance x from the needle tip to the uterine cavity in the CT image and record the image layer number p from the tumor target position (7) to the bottom surface of the applicator cylinder (1). According to the coordinate system area, the direction, angle and depth of the implant needle to enter the patient's body are obtained, and the implant inlet (5) required by the implant needle is determined. Then, a matching implant needle channel (3) is selected for implantation. The total length of the implant needle is preset to a fixed value L, L = L1 + L2 + L3, L1 is the remaining length of the implant needle outside the patient's body, which can be measured during the implantation process, L2 is the length of the implant needle inside the tortuous implant applicator, and the integral calculation is h + 0.2 cm, h is the height of the tortuous implant applicator, and L3 is the length of the implant needle entering the patient's tumor. During the implantation process, the length of L1 is observed and its length is actually measured. Step 4: Based on the CT scanning layer thickness of 0.1cm-0.5cm in step 3, the distance from the tumor target (7) to the lower surface of the applicator is Δ y =(0.1-0.5)p, then through Right now Calculate the depth L3 that the implant needle needs to enter into the patient's tumor, and then obtain L1 = L-L2-L3. Finally, compare the theoretical calculated value L1 of the implant needle entering the patient's tumor with the length L1 of the implant needle remaining outside the patient's body measured in step 3 to obtain the implant depth of the implant needle accurately inserted into the tumor target site (7) during the implantation process; Step 5: Finally, the CT device scans the image again, inserts the pointed flexible implant needle into the matching implant needle channel (3), and then removes the needle core to ensure that the implant needle channel (3) is hollow. Then, the after-loading radiation source is used to perform close-range precision radiotherapy on the tumor target (7).