Teaching die body and teaching evaluation method for implantation between pelvic tissues

Abstract

The invention discloses a pelvic cavity tissue implantation teaching model body and a teaching evaluation method, and the model body comprises a pelvic cavity shell model body which is used for simulating an external anatomical structure of a human pelvic cavity and can be detached into two parts which are in bilateral symmetry, and the interiors of the two parts respectively comprise pelvic bone structures; the target region endangered organ die body is arranged in a space formed by folding the left part and the right part of the pelvic cavity shell die body and is used for simulating a real target region tissue and a surrounding organ at risk, and two parallel gaps which are spaced at a fixed distance are formed in the die body; the coordinate paper acquisition system comprises two pieces of coordinate paper which are arranged in parallel, and the two pieces of coordinate paper are respectively arranged in two parallel gaps on the target region endangered organ mold body and are used for recording the spatial position information of the implanting needle; and the connecting handle is detachably connected with the target region endangering organ die body through a first standardized interface, and a whole formed by connecting the target region endangering organ die body and the connecting handle is detachably connected with the left part and the right part of the pelvic cavity shell die body through a second standardized interface.

Description

Technical Field

[0001] This invention relates to the field of brachytherapy for cervical cancer, and more particularly to a teaching model for interstitial implantation in the pelvic cavity and a teaching assessment method. Background Technology

[0002] Brachytherapy is an indispensable part of radical radiotherapy for cervical cancer and cannot be replaced by any external beam radiation. Intracavitary and / or interstitial implantation is often necessary because intracavitary radiotherapy cannot meet clinical needs due to large tumor size, eccentric location, irregular shape, involvement of the parametrial region, or vaginal stenosis. Combining intracavitary and / or interstitial implantation can better cover the target area and improve efficacy. However, interstitial implantation is limited by the operator's skill level; different operators have different implantation sites and efficacy, making its clinical implementation difficult.

[0003] Currently, pelvic teaching models for cervical cancer mostly use human skeletal models or simulated silicone models. However, these models cannot fully simulate the implantation treatment process for cervical cancer. As a result, current teaching still relies on experience, written videos, and patient practice. It is impossible to confirm whether the learner's placement of the implantation needle in the tissue is accurate. At the same time, there is no way to judge whether the learner's mastery is mature, and there are no evaluation standards. Consequently, few doctors are able to perform the implantation operation, and brachytherapy for cervical cancer cannot be widely popularized.

[0004] Currently, teaching methods for cervical cancer treatment mainly rely on text, video interpretation, or image analysis, as well as hands-on teaching and learning on patients. However, videos and images alone cannot fully convey the location of the incision points, and the quality of teaching cannot be guaranteed. Demonstrations on patients can cause discomfort and fear, and teaching opportunities are limited; cases vary, which is detrimental to classroom teaching. Furthermore, during teaching, it is impossible to determine whether the medical student's operation is correct, or even to verify the dosage. This may result in insertions not reaching the predetermined location or passing through the predetermined location, leading to repeated insertions and increasing patient discomfort. Therefore, the only way to improve doctors' skills is through repeated hands-on practice. Summary of the Invention

[0005] This invention addresses the teaching needs of interstitial implantation techniques in gynecologic tumor brachytherapy by proposing a pelvic interstitial implantation teaching phantom and a teaching assessment method. The phantom adopts a fully modular design, and the coordinate paper system is a flexible, independent module. By changing different target area phantoms, a single basic pelvic shell can be adapted to various clinical cases. Furthermore, the teaching assessment method of this invention provides a complete standardized teaching and assessment closed-loop process.

[0006] To achieve the above objectives, the present invention provides a pelvic interstitial implantation teaching phantom, comprising the following parts: a pelvic shell phantom for simulating the external anatomical structure of the human pelvis, wherein the pelvic shell phantom can be disassembled into two symmetrical parts, each containing a pelvic bone structure; a target area organ at risk phantom, installed within the space where the left and right parts of the pelvic shell phantom are joined, for simulating real target area tissues and surrounding organs at risk, wherein the target area organ at risk phantom has two parallel slits spaced at a fixed distance; a coordinate paper acquisition system comprising two parallel coordinate papers for recording the spatial position information of the implantation needle, wherein the two coordinate papers are respectively installed in the two parallel slits on the target area organ at risk phantom; and a connecting handle for detachably connecting to the target area organ at risk phantom via a first standardized interface, wherein the entire assembly of the target area organ at risk phantom and the connecting handle is detachably connected to the left and right parts of the pelvic shell phantom via a second standardized interface.

[0007] Furthermore, the first standardized interface is a protrusion / groove structure provided on the detachable connecting handle, and a matching groove / protrusion structure provided on the target area organ at risk phantom; the second standardized interface is a protrusion / groove structure provided on the left and right parts of the pelvic shell phantom, and a matching groove / protrusion structure provided on both sides of the target area organ at risk phantom and the detachable connecting handle.

[0008] Furthermore, an adjustable rubber ring is provided at the vaginal opening of the pelvic cavity outer shell mold to read the remaining length of the insertion needle outside the vaginal opening.

[0009] Furthermore, the pelvic cavity shell phantom is manufactured using three-dimensional modeling and 3D printing integrated molding technology. The pelvic skin is made of PLA material, and the pelvic bone structure is made separately using a mixture of silicone and plaster powder. In addition, when making the target area organ at risk phantom, the anatomical morphology of the target area organ at risk is designed through three-dimensional modeling, and silicone is cast and molded using a special mold.

[0010] The technical solution of the present invention also provides a teaching and evaluation method for interstitial pelvic implantation, which uses the interstitial pelvic implantation teaching model as described above. The method includes the following steps: Step 1: Perform implantation operation in the interstitial pelvic implantation teaching model, with the implantation needle passing through two coordinate papers in sequence; Step 2: After completing the implantation operation of all implantation needles, disassemble the interstitial pelvic implantation teaching model and remove the two coordinate papers; Step 3: Read the coordinate data S1 and S2 recorded on the two coordinate papers respectively, and the remaining length L of the implantation needle outside the vaginal opening obtained by marking with a rubber band; Step 4: Input the data collected in Step 3 into the scoring software system. The scoring software system performs quantitative analysis according to the preset scoring criteria and automatically generates a comprehensive score for the corresponding implantation operation.

[0011] Further, in Step 1, the pelvic interstitial implantation teaching phantom is assembled according to the following steps: S11: Install coordinate paper, placing two coordinate papers into the two gaps of the target area organ at risk phantom respectively; S12: Connect the connecting handle to the target area organ at risk phantom through the first standardized interface; S13: Connect the pelvic shell phantom, placing the assembled connecting handle and the target area organ at risk phantom in the middle position, closing the left and right parts of the pelvic shell phantom and connecting them to the connecting handle and the target area organ at risk phantom through the second standardized interface.

[0012] Furthermore, the method enables teaching and training in various scenarios by pre-setting multiple target area endangered organ phantoms with different configurations and by repeatedly replacing the target area endangered organ phantoms in the pelvic interstitial implantation teaching phantom. When it is necessary to replace the target area endangered organ phantom, the target area endangered organ phantom is directly removed from the connecting handle and the pelvic shell phantom, and the new target area endangered organ phantom is reconnected to the left and right parts of the connecting handle and the pelvic shell phantom through the first standardized interface and the second standardized interface.

[0013] Furthermore, in Step 1, the following three implantation methods are supported: manual implantation, radiotherapy guide plate-assisted implantation, and image-guided implantation.

[0014] Furthermore, in Step 4, the scoring software system uses a preset three-dimensional model and geometric calculation algorithm to automatically calculate the three-dimensional position of each implantation needle in the pelvic tissue insertion teaching model, and then performs quantitative analysis according to the preset scoring criteria. The three-dimensional model is used to represent the spatial position and geometric shape of each tissue structure in the pelvic tissue insertion teaching model.

[0015] Further, in step 4, the geometric calculation algorithm of the scoring software system calculates the three-dimensional position of the implanted needle according to the following steps: S41: Calculate the direction vector of the needle path based on S1 and S2 and the fixed distance D between the two coordinate papers; S42: Calculate the three-dimensional coordinates S3 of the needle tip based on the direction vector and the insertion depth ML of the implanted needle, where M is the total length of the implanted needle; S43: Compare the needle tip coordinates S3 with the target area and the location of the organs at risk in the three-dimensional model to calculate the relationship between the corresponding implanted needle and each anatomical structure.

[0016] Furthermore, in Step 4, the scoring software system generates targeted improvement suggestions based on the analysis results. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the components of the pelvic cavity phantom of the present invention;

[0019] Figure 2 This is the BOM diagram of the pelvic cavity phantom of the present invention;

[0020] Figure 3 This is a schematic diagram of the replaceable target area and organ at risk phantom of the present invention;

[0021] Figure 4 This is a schematic diagram of the coordinate paper placement position according to the present invention;

[0022] Figure 5 This is a schematic diagram of the graph paper that can be used in this invention;

[0023] Figure 6 This is a geometric diagram of the insertion process of the present invention;

[0024] Figure 7 This is a flowchart of the operation method of the present invention;

[0025] Figure 8 This is a schematic diagram illustrating the insertion practice of the radiotherapy guide plate of the present invention;

[0026] Figure 9 This is a schematic diagram of CT image-guided implantation according to the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] This invention addresses the teaching needs of interstitial implantation techniques in gynecologic oncology brachytherapy by proposing a complete teaching evaluation system. Its core principles are: standardizing implantation procedures, quantifying evaluation, and automating feedback.

[0029] To address this, this invention designs a closed-loop system consisting of three components: hardware, data acquisition, and software scoring. The hardware component provides a standardized phantom that simulates real-world operation; the data acquisition component accurately records the spatial position of the inserted needles during the trainee's operation; and the scoring component automatically evaluates the operation quality and provides feedback based on the needle position information using an algorithm. The specific technical implementation schemes for each of these three components are described in detail below.

[0030] like Figure 1 As shown, in terms of hardware, the present invention provides a pelvic cavity teaching phantom, which includes the following parts:

[0031] (1) Detachable pelvic shell mold

[0032] A detachable pelvic shell phantom ① is used to simulate the external anatomical structure of the patient's pelvis, providing a standardized operating space for implantation procedures. For example... Figure 2 As shown, the left and right pelvic shells ① also contain pelvic phantoms ② to better simulate the actual situation during clinical treatment and provide reference position information during image-guided implantation. The shell phantoms feature a detachable design and have standardized mounting interfaces with the target area organ-at-risk phantoms, supporting rapid disassembly and installation. The pelvic shells themselves can be manufactured in different sizes to meet various teaching needs (such as different patient body types).

[0033] The detachable design allows trainees to easily install and replace different target area and organ-at-risk phantoms, simulating clinical scenarios where treatment plans are adjusted for different patients or the same patient. Through repeated assembly and disassembly, trainees can deepen their understanding of pelvic anatomy, target area location, and the relative positions of organs at risk. This design enables flexible combinations of a basic pelvic shell with multiple target area phantoms, improving hardware versatility and utilization efficiency while reducing teaching costs.

[0034] (2) Replaceable and customizable target area organ at risk phantom

[0035] The target area and organ at risk phantom ③ is installed inside the pelvic shell to simulate real target area tissue and surrounding organs at risk. This phantom includes a target area portion (cervical / uterine body target area, representing the tumor site requiring radiotherapy) and an organ at risk portion (surrounding normal tissues and organs, including the bladder, rectum, fallopian tubes, etc., representing clinically risky organs requiring protection), such as... Figure 3 As shown.

[0036] This invention provides multiple sets of target area phantoms with different configurations to meet diverse clinical teaching needs. These include target area phantoms of different tumor sizes (e.g., small, medium, and large lesions), combinations of different locations and anatomical variations of organs at risk (e.g., bladder displacement, rectal repositioning), and different levels of clinical complexity (from simple single-target phantoms to complex combinations of multiple risk factors). By changing different target area phantoms and performing multiple procedures, trainees can cope with various anatomical variations and case complexities encountered in clinical practice. Through the simulation of different tissue characteristics using different materials, trainees gain near-realistic puncture tactile sensation and feedback during training, enhancing the clinical applicability of the procedure. Through modular design and customizability, a basic pelvic shell can be paired with multiple target area phantoms, satisfying a complete teaching sequence from basic to advanced levels. Repeated training with multiple phantoms of different configurations allows trainees to more comprehensively master insertion techniques in different clinical scenarios, improving clinical adaptability.

[0037] (3) Graph paper acquisition system

[0038] The coordinate paper acquisition system ⑤ is a key component of this invention for accurately acquiring the spatial position information of the implanted needles. For example... Figure 4 As shown, the coordinate paper is installed inside the phantom. Each insertion pin leaves a precise position mark on the coordinate paper as it passes through the target area and enters the coordinate paper. The coordinate paper uses common teaching coordinate paper (such as...). Figure 5 It can accurately record the position of the needle hole with millimeter-level precision, and can make directional marks according to the actual situation during use. Each needle leaves a puncture hole on the graph paper as it passes through, forming a two-dimensional coordinate mark of the needle on the corresponding coordinate. The graph paper is pre-printed on the bottom or surface for easy and accurate reading of the coordinate values ​​later.

[0039] Traditional position acquisition methods often employ complex sensor arrays (such as optical sensors and electromagnetic sensors), resulting in high costs, integration difficulties, and susceptibility to failure. This invention utilizes a physical marking scheme using coordinate paper, completely avoiding the complexity of electronic sensors. Through precise marking and readings on the coordinate paper, the trainee's insertion operations in three-dimensional physical space are accurately converted into calculable digital coordinate data, providing an accurate input data source for subsequent software scoring. Since the coordinate paper is an independent module within the phantom, it can be replaced or adjusted according to different target area phantoms, fully compatible with the phantom's detachable design. As a passive physical recording medium, the coordinate paper requires no power supply, is not easily damaged, and requires no maintenance, significantly reducing the overall system cost and failure risk. Trainees can intuitively see the position markings of each needle on the coordinate paper, understanding the results of their operations, enhancing transparency and credibility.

[0040] (4) Detachable connecting handle

[0041] like Figure 2 As shown, the detachable connecting handle ④ is used for detachable connection with the target area organ at risk phantom ③. After the two are connected as a whole, they are then detachably connected to the left and right parts of the pelvic shell phantom ①.

[0042] Since the target area critical organ phantom is usually small in size, in this invention, the connection to the left and right parts of the pelvic cavity shell is further achieved by a connecting handle. Since the connecting handle is provided with a protrusion / groove structure for connecting to the left and right parts of the pelvic cavity shell phantom, only a short protrusion / groove structure needs to be provided on the target area critical organ phantom, which makes it easier to adapt to the installation of different target area critical organ phantoms.

[0043] The hardware phantom manufacturing of this invention comprises three main parts: a pelvic shell phantom, a target area organ at risk phantom, and a coordinate paper system.

[0044] The pelvic cavity outer shell is manufactured using 3D printing integrated molding technology. First, the precise geometric dimensions and anatomical structure of the left and right pelvic bones are determined through 3D modeling. The pelvic skin is made of PLA material and 3D printed in one piece. PLA material has a certain degree of hardness, effectively simulating the mechanical properties of the human pelvis while providing sufficient support for the internal tissues and skeletal structure. The internal pelvic bone structure is fabricated separately using a mixture of silicone and plaster powder for casting. Its density is close to that of real bone, ensuring that the overall model's biomechanical properties closely resemble those of the human body, facilitating realistic training experiences in teaching operations. Each left and right pelvic bone is divided into two parts, which are connected by grooves to the target area's organ-endangering modules. This ensures a tight fit between the pelvis and the organ modules while also enabling the overall model to be disassembled. Surface treatment ensures the smoothness of the pelvic skin and installation accuracy. Component processing completes the standard location coding of puncture points and the manufacturing of various installation interfaces. Finally, quality inspection ensures the interchangeability of all components.

[0045] The manufacturing process for the target area and organ at-risk phantom is as follows: 3D modeling → mold manufacturing → silicone casting → manual optimization → assembly → functional testing. The anatomical morphology of the target area and organs at-risk (bladder, rectum, etc.) is precisely designed through 3D modeling, and a specialized mold is manufactured to support silicone casting. All organ components are made of silicone material. After casting, manual optimization is performed to precisely adjust the material's hardness and feel, ensuring it closely resembles the puncture feel and resistance characteristics of real tissue. Finally, assembly and functional testing are conducted to ensure the anatomical accuracy, usability, and safety of the organ phantom. This material selection and manufacturing process allows the pelvic bone structures and organs to closely resemble the human body, providing trainees with a more realistic clinical experience and reducing the need for repeated trial and error during procedures.

[0046] The coordinate paper system employs a design using two parallel coordinate papers. These two papers are placed within the target area critical organ phantom and spaced a fixed distance apart, typically 30-60 mm. Two gaps are provided on the target area critical organ phantom for placing and removing the coordinate papers, facilitating their installation, removal, and replacement. The space between the two coordinate papers is used to record the spatial position information of the implantation needle. As the needle passes through both coordinate papers sequentially, a mark is formed on each, allowing for precise determination of the needle's three-dimensional coordinates.

[0047] The manufacturing process of this invention has the following core features. Modular design ensures the interchangeability and reusability of each component (outer shell phantom, target area / organ at risk phantom, coordinate paper), allowing for flexible combination of components with different configurations. One outer shell phantom can be paired with multiple different target area phantoms, significantly improving the overall system's utilization efficiency and cost-effectiveness. The scientific selection of target area and organ at risk materials, based on the biomechanical properties of real tissues (such as hardness, elastic modulus, puncture resistance, etc.), makes the phantom's feel and resistance as close as possible to real tissue, allowing trainees' operational experience on the phantom to be as close as possible to clinical operation, enhancing the clinical translation effect of training. The acquisition system composed of two parallel coordinate papers achieves millimeter-level accuracy, sufficient to accurately record the position of the implantation needle in three-dimensional space, providing high-quality input data for subsequent software scoring algorithms.

[0048] In the software aspect, the technical solution of this invention also provides teaching assessment software, which mainly includes the following aspects:

[0049] (1) Principle of three-dimensional spatial positioning based on two coordinate sheets

[0050] This invention employs a design using two parallel coordinate sheets to precisely determine the position of the insertion pin in three-dimensional space. The two coordinate sheets are located at different depths within the phantom, separated by a known fixed distance. For example... Figure 6 As shown, when the trainee performs the implantation operation, each implantation needle passes through two graph papers in sequence, leaving a puncture hole mark on each paper, denoted as . and .

[0051] The location of the puncture hole for the implantation needle on the first graph paper has horizontal and vertical axes. . The location of the puncture hole for the implantation needle on the second graph paper has horizontal and vertical axes. Since the distance between the two graph papers is a known fixed value. Therefore, according to and The coordinate information is used to calculate the precise direction vector of the implantation needle channel in space. Specifically, the direction of the needle channel can be expressed as: This vector reflects the three-dimensional spatial trajectory of the needle as it enters the first coordinate paper and exits the second.

[0052] (2) Calculation of needle tip position S3

[0053] To determine the precise position of the tip of the implantation needle in three-dimensional space (denoted as ). This invention employs a key design feature: an adjustable rubber ring marker is placed at the vaginal opening of the mold. After the trainee completes the insertion operation, the rubber ring is adjusted to contact the vaginal opening. At this point, the remaining length of the insertion needle outside the vaginal opening can be directly read and recorded as follows: Due to the total length of the implantation needle Since it is known and fixed, the effective length of the insertion pin that has entered the phantom is... .

[0054] Combination , The needle path direction determined by the two coordinate points, and the length already traveled. It can accurately calculate the needle tip The position coordinates within the three-dimensional space of the phantom. The calculation process is as follows: using... Starting from, along the path from , Distance traveled by a determined direction vector The endpoint reached is the position of the needle tip. The three-dimensional coordinates.

[0055] (3) Three-dimensional model and software calculation

[0056] To achieve automated needle path analysis and scoring, this invention pre-loads multiple established 3D models into the software. These 3D models accurately represent the spatial location and geometry of various tissue structures (target area, organs at risk, etc.) within the phantom, including information on the distance D between the two coordinate sheets.

[0057] After completing the operation, the student or teacher should input the following parameters into the software system: (Coordinates of the puncture hole on the first coordinate paper) (Coordinates of the puncture hole on the second coordinate paper) (The remaining needle length at the vaginal opening) (Total length of implanted needles). Based on these input parameters, the software automatically calculates the precise three-dimensional position of each implanted needle in the model using the built-in 3D model and geometric calculation algorithms.

[0058] The specific calculation steps are as follows: First, according to and Given the coordinates of the two papers and the known distance D between them, calculate the direction vector of the needle track; secondly, based on the direction vector and the depth of entry... Calculate the needle tip The third step is to obtain the three-dimensional coordinates of the needle tip; The software compares the needle's position with the target area and organs at risk in the 3D model to calculate the relationship between the needle and various anatomical structures. In this way, the software can accurately determine the positional distribution of all implanted needles within the phantom. When using multiple needles for implantation, multiple perforation locations will be left on two coordinate sheets. The software uses the distance relationship between the vaginal opening and the two coordinate sheets to constrain the spatial angle and physical position of the implanted needles, thereby enabling precise identification of the position of each needle.

[0059] (4) Automatic scoring and feedback based on needle path location

[0060] Once the software calculates the precise positions of all implanted needles in the 3D model, subsequent scoring and feedback generation can begin. Based on this needle placement information, the software performs quantitative analysis according to preset scoring criteria (such as target area coverage, needle-to-needle distance, and extent of organ invasion), automatically generating a comprehensive score for the implantation procedure. Simultaneously, the software generates targeted improvement suggestions based on the analysis results, guiding trainees to understand their operational shortcomings and providing clear directions for improvement in future training sessions.

[0061] This design enables a seamless transition from the physical operation space to the digital analysis space, ensuring that the evaluation of each operation is based on precise geometric data. This guarantees the objectivity and repeatability of the scoring while significantly improving the efficiency and accuracy of teaching feedback.

[0062] See Figure 7 The teaching evaluation of the pelvic phantom provided by this invention includes:

[0063] (1) Assembly process of the model

[0064] Step 1: Installation of Graph Papers. Place two disposable graph papers into the two pre-drilled slots on the target area organ at risk phantom. The two graph papers are installed through the two independent slots, with a known fixed distance between them. After the graph papers are installed, the internal configuration of the target area organ at risk phantom is complete.

[0065] Step 2: Connecting the handle to the organ module. The handle is connected to the organ at risk and target area module via a wedge-shaped groove structure (trapezoidal groove and protrusion). Specifically, the trapezoidal protrusion on the handle is aligned with the trapezoidal groove on the organ at risk and target area module. By sliding along the groove, the handle is inserted into the organ at risk and target area module until the two are completely fitted together, forming a reliable and non-detachable connection. This connection method ensures the stability between the handle and the organ module and facilitates subsequent disassembly operations.

[0066] Step 3: Closing the left and right pelvic cavity phantoms. Place the assembled handle and the endangered organ and target area module in the middle position, and then close the left and right pelvic cavity phantoms. Each of the left and right pelvic cavity phantoms has a trapezoidal protrusion, which is aligned with the grooves on both sides of the handle and the endangered organ and target area module, respectively.

[0067] Step 4: Connecting the pelvic cavity phantom to the organ modules. By sliding the trapezoidal protrusions of the left and right pelvic cavity phantoms along the groove direction, insert them into the handles and the trapezoidal grooves on both sides of the endangered organ and target area modules, respectively, until the left and right pelvic cavities are completely closed and form a tight, integrated connection with the organ modules. At this point, the entire phantom assembly is complete, forming a closed and structurally stable training system.

[0068] (2) Planting process

[0069] After the phantom is assembled, trainees practice insertion techniques. This invention supports three different insertion methods to adapt to different clinical teaching needs and trainees' advanced learning processes.

[0070] Method 1: Manual Insertion. Trainees rely entirely on their own anatomical knowledge, tactile feedback, and clinical experience to perform free-hand insertion operations on the phantom. Through the puncture resistance feedback provided by different materials within the phantom (silicone target area, silicone organ), and because the purposes of the silicone target area and silicone organ differ, trainees can perceive the tactile changes when passing through different tissue layers, learn to identify tissue interfaces, and master standardized insertion techniques.

[0071] Method 2: Radiation therapy guide-assisted implantation. Trainees use a radiation therapy guide as an auxiliary tool (e.g., Figure 8 As shown in the diagram, the placement and angle of the insertion needle are guided by pre-set holes on the template. This method improves the standardization and repeatability of the operation, making it suitable for advanced training after students have mastered basic anatomical knowledge.

[0072] Method 3: Image-guided implantation. Trainees perform implantation procedures under the guidance of real-time images (such as 3D CT or X-ray fluorescence fluoroscopy). Figure 9 (As shown). This method is closest to modern clinical practice, but it has the highest requirements for equipment and technology, and is suitable for advanced training for trainees with a certain foundation.

[0073] Regardless of the insertion method used, trainees operate on the same phantom system. Each insertion needle passes through two coordinate sheets in sequence, leaving a puncture hole mark on the sheets. Once all insertion needles have been inserted, the operation proceeds to the next stage.

[0074] (3) Collection of coordinate data

[0075] Step 5: Removal and Reading of Graph Paper. After all implantation needles have been inserted, the graph paper needs to be removed to obtain positional data. This process is the reverse of the phantom assembly process, using reverse disassembly: first, the left and right pelvic phantoms are removed from the grooves of the organ modules by sliding them in the opposite direction, then the handles are removed from the grooves of the organ modules, and finally, the two disposable graph papers are removed one by one from the two gaps in front of the organ and target area modules.

[0076] After removing the coordinate paper, the student or teacher should accurately read the location of the puncture hole for each implantation needle using the standard reading method. The coordinates of the puncture holes on the first coordinate paper are marked as S1 (inclusive). and On the second coordinate paper, the coordinates of the puncture hole corresponding to the needle are marked as S2 (inclusive). and Simultaneously, the remaining length L of the implanted needle outside the vaginal opening, obtained by marking with a rubber band during the operation, was recorded.

[0077] (4) Software scoring

[0078] Step 6: Data Input and Scoring. Input the collected coordinate data into the scoring software system. The specific input data includes: S1 (the coordinates of the puncture hole on the first coordinate paper), S2 (the coordinates of the puncture hole on the second coordinate paper), L (the remaining needle length outside the vaginal opening), and M (the known total length of the inserted needle).

[0079] After receiving these parameters, the software system uses its built-in 3D model and geometric calculation algorithms to automatically calculate the precise 3D position of each implantation needle within the phantom. Then, based on preset scoring criteria (target area coverage, needle-to-needle distance, safe distance to organs at risk, etc.), it performs quantitative analysis, generating a comprehensive scoring report and targeted improvement suggestions for the implantation operation. Through this feedback, trainees understand the strengths and weaknesses of their operation, providing clear directions for improvement in future training sessions.

[0080] This operational process forms a complete closed loop: phantom assembly → insertion operation → data collection → software scoring → feedback and guidance, ensuring the standardization of teaching and the objectivity of assessment.

[0081] The technical solution of this invention mainly includes the following points:

[0082] Key Point 1: A quantifiable planting effect scoring algorithm based on geometric relationships

[0083] The technical problem to be solved:

[0084] Interstitial implantation techniques demand extremely high precision, but current teaching methods suffer from serious assessment deficiencies. First, existing assessment methods rely entirely on the subjective judgment and clinical experience of the supervising physician. Different physicians may have vastly different evaluation criteria for the same procedure, resulting in a lack of objectivity and repeatability in the assessments, and trainees cannot obtain clear, quantifiable areas for improvement. Second, current hardware technology is limited. Using complex electronic sensors for automated data acquisition and scoring presents challenges such as high cost, integration difficulties, and susceptibility to failure. Furthermore, these sensors are often incompatible with detachable, modular phantom designs.

[0085] Specific improvement plan:

[0086] This invention innovatively employs a physical marking system using two parallel coordinate papers, combined with rubber band length marking, to achieve precise acquisition of the three-dimensional spatial position of the implanted needles. Based on this, a complete geometric relationship analysis and scoring algorithm is established. The core of this algorithm is: taking the acquired coordinates of multiple needle points (S1, S2, L, M) as input, and calculating key geometric parameters such as the direction vector of the needle path, the distance and angle between adjacent needles, the coverage of the entire needle group on the target area, and the safe distance from organs at risk, according to preset scoring standards and weights, it automatically generates an objective and accurate comprehensive score.

[0087] The scoring of this invention is entirely based on objective mathematical parameters. Regardless of when, where, or by whom the same operational data is scored, the results are completely consistent, ensuring repeatability and fairness. Precise quantification of operational quality: It accurately reflects key indicators such as target area coverage, the rationality of needle distribution, and adherence to safety boundaries, making the scoring results both accurate and interpretable, allowing trainees to clearly understand the meaning of each scoring point. Support for instant feedback: A scoring report is generated immediately after the operation, eliminating the need to wait for the instructor's subjective evaluation, significantly accelerating the feedback loop and improving teaching efficiency. Cost and reliability advantages: The physical marking scheme of graph paper completely avoids the cost and maintenance problems of complex electronic sensors, making the entire system low-cost, highly reliable, and easy to promote.

[0088] Key Point Two: Repeatable and Customizable Modular Phantom Design

[0089] The technical problem to be solved:

[0090] Existing interstitial implantation teaching phantoms are typically fixed configurations, which have the following limitations: From a teaching adaptability perspective: In real-world clinical settings, patients exhibit significant differences in anatomical structure (e.g., different tumor sizes, different locations of organs at risk, different anatomical variations), but fixed phantoms cannot simulate these variations, resulting in a limited training scenario and restricted clinical adaptability for trainees. From a hardware utilization efficiency perspective: One phantom can only correspond to one configuration. To cover multiple clinical scenarios, multiple complete hardware sets need to be purchased, leading to high costs and low utilization efficiency. From a hardware design perspective: Traditional integrated designs make phantom updates and iterations difficult. If a component fails, the entire phantom often needs to be replaced, resulting in high maintenance costs.

[0091] Specific improvement plan:

[0092] This invention employs a fully modular design: the pelvic shell and the target area organ at risk phantom are detachably connected via a standardized trapezoidal groove-protrusion interface, and the coordinate paper system is a flexible, independent module. Simultaneously, multiple sets of target area organ at risk phantoms with different configurations are prefabricated, including combinations of target areas with different tumor sizes, different organ at risk locations, and different levels of clinical complexity, forming a complete "question bank."

[0093] This invention provides a basic hardware system applicable to various teaching scenarios: by changing different target area phantoms, a single basic pelvic shell can adapt to multiple clinical cases, avoiding the costly waste of repeatedly purchasing complete hardware and significantly improving hardware utilization efficiency and cost-effectiveness. It supports phased and tiered teaching: trainees can start with simple anatomical configurations and gradually progress to complex anatomical variations and risk factor combinations, forming a scientific and progressive learning path, enhancing the relevance and effectiveness of teaching. It enhances clinical adaptability: through repeated training with multiple phantom configurations, trainees can comprehensively master insertion techniques in different clinical scenarios, enabling them to quickly adapt to various patient anatomical conditions after entering clinical practice, reducing the learning cycle. Flexible hardware maintenance: the modular design means that if a single component is damaged, only that component needs to be replaced instead of the entire phantom, significantly reducing maintenance costs and supporting continuous optimization and iteration of the phantom.

[0094] Key Point 3: A complete standardized teaching and assessment closed-loop process

[0095] The technical problem to be solved:

[0096] Traditional inter-organizational teaching processes are often unstandardized and unsystematic, exhibiting several shortcomings. From a teaching management perspective: the teaching process lacks standardized, traceable data records, making it difficult to quantify and assess student progress, identify differences in student levels within a class, and hinder teachers from implementing data-driven teaching improvements. From an operational standardization perspective: different students and teachers may employ different procedures and assessment standards, resulting in poor consistency and comparability in teaching. From a learning outcomes perspective: students often lack clear directions for improvement and continuous progress feedback, easily leading to a situation where they "know what" but not "why," resulting in low learning efficiency.

[0097] Specific improvement plan:

[0098] This invention organically integrates phantom assembly, insertion operation, coordinate data acquisition, software scoring, and feedback guidance into a complete and standardized closed-loop process. Specifically, the phantom assembly process employs standardized and repeatable steps (trapezoidal groove-protrusion sliding connection) to ensure consistency in each assembly. The insertion operation supports multiple methods (hand, guide plate, image guidance), but the coordinate data acquisition method is uniformly standardized (reading S1, S2, L through coordinate paper). The software scoring uses a standardized scoring system and weights, and all data is automatically saved, supporting both vertical and horizontal data analysis.

[0099] This invention achieves standardization and comparability in teaching. All students train under the same hardware, operating procedures, and scoring standards, making the teaching effects comparable across different times and locations, facilitating the monitoring and improvement of teaching quality. Scientific tracking of student progress: All operational data is fully recorded, supporting longitudinal progress analysis of individual students (student improvement trajectory) and horizontal benchmarking analysis of classes (comparison of levels among students), upgrading teaching management from "experience-based" to "data-driven." Clear and immediate student feedback: After each operation, students immediately receive quantitative, specific, and targeted improvement suggestions, rather than vague qualitative evaluations, significantly accelerating the learning cycle and improving learning efficiency. Optimized allocation of teaching resources: Through data analysis, teachers can quickly identify weak points within the class and students requiring special attention, enabling targeted personalized guidance and improving the utilization efficiency of teaching resources.

[0100] The beneficial technical effects of the technical solution of the present invention include:

[0101] (1) Solve the problem of subjective evaluation and achieve objective quantitative scoring.

[0102] In traditional interstitial implantation training, trainee assessment relies primarily on the subjective judgment of the supervising physician. This assessment method has significant limitations: different supervising physicians may use different scoring standards, and the same trainee may receive different scores at different times and under different supervising physicians, making it difficult to guarantee the repeatability and consistency of the scoring results.

[0103] This invention employs a geometrically based quantitative scoring algorithm, evaluating performance entirely based on objective mathematical parameters (needle path direction, inter-needle distance, target area coverage, and safe distance to organs at risk, etc.), completely eliminating the influence of subjective factors. When the same operational data is input into the system, the scoring results are completely consistent regardless of when, where, or by whom the scoring is performed. This objective scoring not only improves the repeatability and fairness of the scoring but, more importantly, enhances its accuracy—the algorithm precisely reflects the rationality of the needle cluster distribution without bias due to differences in the experience or subjective tendencies of the guiding physician.

[0104] (2) Solve the problem of difficulty in standardization comparison and support progress tracking and data analysis.

[0105] In traditional teaching, due to inconsistent grading standards, it is difficult to track students' learning progress longitudinally and benchmark against others. Questions such as how well each student is learning, what the overall learning progress is, and where the differences in skill levels lie between students are difficult to answer using quantitative data.

[0106] The system of this invention generates standardized, quantifiable scoring data for each operation, and all data is automatically saved. This enables teaching administrators and students to: conduct longitudinal analysis, tracking the progress curve of individual students and clearly seeing their improvement trajectory across multiple training sessions; conduct lateral analysis, comparing the operational levels of different students and identifying outstanding students and those requiring special attention within the class; and conduct dimensional analysis, understanding each student's strengths and weaknesses in various aspects such as target area coverage, needle uniformity, and safety, thereby providing targeted guidance. Such data-driven management significantly improves the scientific and systematic nature of teaching.

[0107] (3) Achieve real-time feedback and significantly improve teaching efficiency

[0108] In traditional one-on-one instruction, after a student completes a procedure, they need to wait for the supervising physician to provide a subjective evaluation, a process that often takes a long time. Moreover, the supervising physician's feedback is often qualitative ("Your procedure is not standardized enough") rather than quantitative ("Your target coverage is 85%, which is 10% lower than the standard 95%), leaving the student with a less clear understanding of their shortcomings.

[0109] The software system of this invention can automatically generate a detailed scoring report immediately after the operation is completed. Trainees can immediately receive: an overall score and grade assessment, detailed scores for each dimension, specific quantitative improvement suggestions (such as "the distance between the 3rd and 4th needles is too small, it is recommended to increase it by 2mm"), and a comparison of progress with previous practice sessions, without waiting. This immediate, quantitative, and specific feedback significantly accelerates the trainee's learning cycle, enabling them to quickly understand problems, make adjustments, and progress rapidly. Compared to the traditional teaching model that requires waiting for the instructor's evaluation, teaching efficiency is significantly improved.

[0110] (4) Reduce hardware and maintenance costs

[0111] Traditional location acquisition solutions often employ complex sensor arrays (such as optical sensors, electromagnetic sensors, etc.). These solutions suffer from serious cost issues: the sensors themselves are expensive, integration and debugging are difficult, and once a sensor malfunctions, it requires professional repair, resulting in high maintenance costs.

[0112] The graph paper physical marking scheme employed in this invention completely avoids the complexity of electronic sensors. As a disposable consumable, the cost of graph paper is negligible compared to that of sensors. Graph paper requires no maintenance, no debugging, and no concern about failure, significantly improving the system's reliability and stability. Furthermore, since the graph paper is reusable, a single hardware module can support an unlimited number of practice sessions, greatly reducing the overall long-term cost. This design makes the teaching system highly cost-effective, facilitating its widespread application in various medical institutions and educational units.

[0113] (5) Improve the accuracy of clinical procedures and enhance the patient's treatment experience.

[0114] Interstitial implantation techniques demand extremely high precision. Traditional teaching methods, due to inadequate assessment and untimely feedback, often require trainees to undergo extensive clinical practice to gradually improve their skills. This directly results in young doctors frequently needing to repeatedly adjust the inserted needle tract in real-world clinical settings due to insufficient skill and precision. This means patients have to endure multiple punctures, increasing discomfort and surgical risks.

[0115] This invention, through a standardized and scientific teaching system, enables trainees to master advanced insertion techniques before entering clinical practice, based on ample practice. When these well-trained doctors enter clinical settings, they can perform insertion procedures with greater precision, significantly reducing the number of adjustments needed to the patient's needle tract. This directly reduces patient discomfort and puncture trauma during the insertion process, improves the patient's treatment experience, and also increases the overall success rate and safety of the treatment.

[0116] (6) Support multi-level teaching needs and enhance the flexibility and applicability of teaching.

[0117] Traditional teaching models often have fixed configurations, making it difficult to adapt to diverse teaching needs. This invention features a detachable and customizable model design, and supports multiple operation methods including freehand, guide plate, and image-guided methods, enabling the system to meet the teaching needs of learners at all levels, from beginners to advanced learners. Beginners can start with simple anatomical models and freehand manipulation, gradually progressing to complex anatomical variations and the combined application of various auxiliary methods. This phased and tiered teaching design enhances the relevance and effectiveness of instruction, allowing each learner to train and progress at an appropriate level of difficulty.

[0118] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A teaching model for interstitial implantation in the pelvic cavity, characterized in that, Includes the following parts: A pelvic cavity shell phantom is used to simulate the external anatomical structure of the human pelvis. The pelvic cavity shell phantom can be disassembled into two symmetrical parts, each containing a pelvic bone structure. The target area endangered organ phantom is installed in the space after the left and right parts of the pelvic shell phantom are closed, and is used to simulate the real target area tissue and surrounding risk organs. The target area endangered organ phantom is provided with two parallel slits with a fixed distance between them. The coordinate paper acquisition system includes two parallel coordinate papers for recording the spatial position information of the implantation needle. The two coordinate papers are respectively installed in two parallel gaps on the target area organ at risk phantom. as well as A connecting handle is provided for detachable connection to the target region organ-at-risk phantom via a first standardized interface, wherein... The target area endangered organ phantom and the connecting handle are connected together and then detachably connected to the left and right parts of the pelvic cavity shell phantom via a second standardized interface.

2. The pelvic tissue insertion teaching model according to claim 1, characterized in that, The first standardized interface is a protrusion / groove structure provided on the detachable connection handle, and a matching groove / protrusion structure provided on the target area organ at risk phantom. The second standardized interface consists of a protrusion / groove structure on the left and right sides of the pelvic cavity shell phantom, and a matching groove / protrusion structure on both sides of the target area organ at risk phantom and the detachable connecting handle.

3. The pelvic tissue insertion teaching model according to claim 1, characterized in that, An adjustable rubber ring is provided at the vaginal opening of the pelvic cavity outer shell mold to read the remaining length of the insertion needle outside the vaginal opening.

4. The pelvic interstitial implantation teaching model according to claim 1, characterized in that, The pelvic cavity outer shell mold is manufactured using 3D modeling and 3D printing integrated molding technology. The pelvic skin is made of PLA material, and the pelvic bone structure is cast using a mixture of silicone and plaster powder. When creating the target area organ at risk phantom, the anatomical morphology of the target area organ at risk is designed through three-dimensional modeling, and silicone is cast and molded using a special mold.

5. A teaching assessment method for interstitial implantation in the pelvic cavity, characterized in that, The method using the pelvic interstitial implantation teaching phantom as described in any one of claims 1-4 includes the following steps: Step 1: Perform the insertion operation in the pelvic tissue insertion teaching model, with the insertion needle passing through two coordinate papers in sequence; Step 2: After completing the insertion of all the insertion needles, disassemble the pelvic interstitial insertion teaching model and take out the two coordinate papers. Step 3: Read the coordinate data S1 and S2 recorded on the two coordinate papers respectively, and the remaining length L of the insertion needle outside the vaginal opening obtained by marking with a rubber band; Step 4: Input the data collected in Step 3 into the scoring software system. The scoring software system performs quantitative analysis according to the preset scoring criteria and automatically generates a comprehensive score for the corresponding planting operation.

6. The pelvic interstitial implantation teaching assessment method according to claim 5, characterized in that, In Step 1, assemble the pelvic interstitial implantation teaching phantom according to the following steps: S11: Install the coordinate paper, placing the two coordinate papers into the two gaps of the target area organ at risk phantom respectively; S12: Connect the connection handle to the target area organ at risk phantom via the first standardized interface; S13: Connect the pelvic shell phantom, place the assembled connecting handle and the target area organ at risk phantom in the middle position, then close the left and right parts of the pelvic shell phantom and connect them to the connecting handle and the target area organ at risk phantom through the second standardized interface.

7. The pelvic interstitial implantation teaching assessment method according to claim 6, characterized in that, The method pre-sets multiple target area endangered organ phantoms with different configurations and achieves teaching and training in various scenarios by repeatedly replacing the target area endangered organ phantoms in the pelvic interstitial implantation teaching phantom. When it is necessary to replace the target area endangered organ phantom, the target area endangered organ phantom is directly removed from the connecting handle and the pelvic shell phantom, and the new target area endangered organ phantom is reconnected to the left and right parts of the connecting handle and the pelvic shell phantom through the first standardized interface and the second standardized interface.

8. The pelvic interstitial implantation teaching assessment method according to claim 5, characterized in that, In Step 1, the following three implantation methods are supported: manual implantation, radiotherapy guide plate-assisted implantation, and image-guided implantation.

9. The pelvic interstitial implantation teaching assessment method according to claim 5, characterized in that, In Step 4, the scoring software system uses a preset 3D model and geometric calculation algorithm to automatically calculate the 3D position of each implantation needle in the pelvic tissue insertion teaching model, and then performs quantitative analysis according to the preset scoring criteria. The 3D model is used to represent the spatial position and geometric shape of each tissue structure in the pelvic tissue insertion teaching model.

10. The pelvic interstitial implantation teaching assessment method according to claim 9, characterized in that, In step 4, the geometric calculation algorithm of the scoring software system calculates the three-dimensional position of the implanted needle according to the following steps: S41: Calculate the direction vector of the needle track based on S1, S2, and the fixed distance D between the two coordinate sheets; S42: Calculate the three-dimensional coordinates S3 of the needle tip based on the direction vector and the insertion depth ML, where M is the total length of the insertion needle; S43: Compare the needle tip coordinates S3 with the target area and organs at risk locations in the 3D model to calculate the relationship between the corresponding implanted needle and each anatomical structure.

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