An ultrasound-guided nasojejunal tube placement teaching simulation system

Abstract

The application discloses an ultrasound-guided nasal-intestinal tube placement teaching simulation system, relates to the technical field of medical teaching simulation, and comprises a high-fidelity bionic gastrointestinal multi-state simulation module, an intelligent tactile feedback and dynamic resistance simulation module, a multi-dimensional ultrasound guidance and positioning precision simulation module, a three-dimensional virtual dissection and whole-process visualized backtracking module, an AI-driven multi-dimensional intelligent evaluation and adaptive teaching module and a whole-cycle data management and teaching supervision module. The system is configured by a bionic gastrointestinal model consistent with the proportion of human dissection and different physiological and pathological states, so that multi-scene simulation of the nasal-intestinal tube placement process is realized. The system is cooperatively operated by the tactile feedback and ultrasound simulation, and simultaneously presents the operation feeling and the ultrasound imaging effect. The operation process of students is evaluated in multiple dimensions, the training content and difficulty are adjusted according to the evaluation results, and closed-loop management of teaching training is realized. The system is suitable for medical college teaching, hospital residency training, critical specialty and nutrition specialty skill examination.

Description

Technical Field

[0001] This invention relates to the field of medical teaching simulation technology, and more specifically, to a teaching simulation system for ultrasound-guided nasoenteric tube placement. Background Technology

[0002] Nasojejunal tube placement is a common and important clinical procedure for critically ill patients, perioperative patients, and those requiring long-term enteral nutrition support. Because the nasojejunal tube must pass sequentially through the nasal cavity, pharynx, esophagus, stomach, and duodenum, the procedure involves a long path and numerous anatomical twists. Improper handling can easily lead to risks such as accidental airway entry, tube entanglement, and misjudgment of placement, thus affecting the effectiveness of nutritional support and even causing serious complications. Therefore, nasojejunal tube placement places high demands on the operator's anatomical knowledge, tactile control, and risk identification abilities.

[0003] To improve the safety and success rate of nasoenteric tube placement, ultrasound-guided technology has been gradually introduced into clinical practice. This technology allows for real-time ultrasound visualization of the tube in the esophagus, stomach, and duodenum, aiding in tube positioning. Compared to traditional blind insertion, ultrasound guidance offers significant advantages such as bedside visualization, non-invasive safety, convenience, speed, and high repeatability. It reduces the risk of accidental airway entry, positioning errors, and delayed positioning during nasoenteric tube placement, improving the timeliness and safety of enteral nutrition. Compared to endoscopic guidance, ultrasound guidance reduces waiting time and treatment costs, alleviating the financial burden on patients, and is now widely used in most tertiary hospitals in China. However, ultrasound-guided nasoenteric tube placement places higher demands on the operator's ultrasound scanning skills, image interpretation experience, and operational coordination. Systematic training in these skills remains a challenge in clinical teaching.

[0004] Currently, the main teaching and training methods for nasoenteric tube placement include bedside demonstrations, video teaching, and simple operational model training. Among these, bedside demonstrations are limited by patient conditions, teaching opportunities, and safety risks, making it difficult to conduct large-scale, repetitive training; while video teaching can demonstrate standard operating procedures, it lacks interactivity, making it difficult for trainees to develop a realistic sense of operation and spatial awareness; existing operational models are mostly static structures, usually only providing fixed resistance or a single pathway, making it difficult to reflect the real operational differences in different anatomical segments and different gastrointestinal functional states.

[0005] Furthermore, in ultrasound-guided teaching, existing teaching systems mostly focus on the display of ultrasound images or basic interpretation training. However, due to the obstruction of human physiological structures and the principles of ultrasound imaging, in actual clinical practice, relatively clear imaging can often only be obtained in limited areas such as the inverted triangle of the esophagus, the fundus of the stomach, or the antrum of the stomach. During training, trainees find it difficult to establish a continuous spatial understanding of the nasoenteric tube throughout the gastrointestinal tract, easily leading to problems such as "images are visible but the path is unclear" and "operation is completed but the principle is not understood."

[0006] On the other hand, existing nasoenteric tube placement teaching systems still have shortcomings in terms of operational feedback and teaching evaluation. Most systems only focus on whether the operation is completed or conforms to the standard, lacking detailed simulation of key operational sensations such as changes in resistance during advancement and retraction upon release. Teaching evaluation is often based on the teacher's subjective experience, lacking a systematic and quantitative assessment of operational standardization, ultrasound interpretation ability, risk avoidance ability, and operational strategy adaptation, making it difficult to provide targeted training and guidance for trainees' weak areas.

[0007] At the same time, existing teaching systems usually lack the means to visualize and trace back and analyze the entire operation process. When the operation fails or an anomaly occurs, students find it difficult to intuitively understand the specific location and cause of the problem, resulting in low teaching feedback efficiency and hindering the rapid improvement of skills.

[0008] Therefore, how to construct a teaching simulation system that can realistically simulate various gastrointestinal functional states during nasoenteric tube insertion, simultaneously present ultrasound guidance effects, provide operational feedback that conforms to clinical feel, and has the ability to visualize and trace the entire process and objectively evaluate teaching, without relying on real patients, remains a technical problem that urgently needs to be solved in the current technology.

[0009] Therefore, there is an urgent need for an ultrasound-guided nasoenteric tube placement teaching simulation system to solve these problems. Summary of the Invention

[0010] The purpose of this invention is to solve the technical problems mentioned in the background section and to provide an ultrasound-guided nasoenteric tube placement teaching simulation system.

[0011] The objective of this invention is achieved through the following technical solution: An ultrasound-guided nasoenteric tube placement teaching simulation system, the system comprising: The high-fidelity bionic gastrointestinal multi-state simulation module is used to construct bionic solid models of the nasal cavity, pharynx, esophagus, stomach, duodenum, jejunum, colon and rectum that are consistent with human proportions, and supports parameterized configuration of various physiological and pathological states. The intelligent tactile feedback and dynamic resistance simulation module is used to output the corresponding propulsion resistance, rebound force and tactile feedback in real time according to the different anatomical segments of the bionic gastrointestinal model and the physiological / pathological state parameters during the propulsion of the nasoenteric tube. The multi-dimensional ultrasound guidance and positioning precision simulation module is used to simulate the ultrasound scanning process, generate ultrasound simulation images that correspond in real time to the actual position of the nasoenteric canal, and support multi-window and multi-angle guidance and positioning training. The 3D virtual anatomy and full-process visualization and backtracking module is used to display the entire process of nasoenteric tube insertion in 3D visualization, and to replay and analyze the insertion path, key nodes and abnormal events after the operation is completed or fails. AI-driven multi-dimensional intelligent assessment and adaptive teaching module is used to quantitatively assess students' operation process, ultrasound interpretation, risk avoidance and strategy selection, and generate personalized teaching feedback and training plans. The full-cycle data management and teaching supervision module is used to uniformly manage student information, training data, evaluation results and teaching records and generate teaching reports; Each module interacts and coordinates with the system control unit.

[0012] As a preferred technical solution of the present invention, the high-fidelity biomimetic gastrointestinal multi-state simulation module includes an anatomical structure biomimetic unit and a physiological / pathological state parameter configuration unit. The anatomical structure biomimetic unit constructs the entire gastrointestinal tract structure according to the proportion of human anatomy, with a size error of no more than ±2%. The physiological / pathological state parameter configuration unit is used to set the gastrointestinal peristalsis frequency, lumen diameter, propulsion resistance coefficient, retraction probability, and sphincter tension parameters.

[0013] As a preferred technical solution of the present invention, the physiological / pathological state parameter configuration unit includes at least the following basic states: It can simulate normal gastrointestinal function, gastroesophageal reflux, insufficient gastric motility, impaired gastric emptying, and gastroparesis, and supports user-defined extended pathological states to simulate scenarios such as intestinal stenosis, pyloric obstruction, or intestinal inflammation.

[0014] As a preferred technical solution of the present invention, the intelligent tactile feedback and dynamic resistance simulation module adopts a segmented resistance simulation method, setting different basic resistance ranges for the nasal cavity-pharynx segment, esophagus segment, stomach segment, pyloric segment and intestinal segment respectively, and dynamically adjusting the resistance magnitude and fluctuation characteristics according to the physiological / pathological state parameters.

[0015] As a preferred technical solution of the present invention, the intelligent tactile feedback and dynamic resistance simulation module includes a push-release-retreat behavior model, which is used to simulate the retreat behavior of the tube after each preset distance is pushed forward, and adjust the retreat distance, retreat speed and retreat probability according to different pathological states.

[0016] As a preferred technical solution of the present invention, the multi-dimensional ultrasound guidance and positioning precision simulation module supports ultrasound simulation imaging of the inverted triangle area of ​​the esophagus, the fundus of the stomach, the body of the stomach, the antrum of the stomach, the horizontal segment of the duodenum, the upper segment of the jejunum and the colon, and simulates the imaging effects under different ultrasound equipment and operating conditions by adjusting the probe frequency, gain, depth and scanning angle.

[0017] As a preferred technical solution of the present invention, the multi-dimensional ultrasound guidance and positioning precision simulation module further includes an ultrasound noise and artifact simulation unit, which is used to introduce ultrasound artifacts related to gastrointestinal gas, tissue interfaces and pathological states, so as to train trainees' ultrasound interpretation and misjudgment identification capabilities.

[0018] As a preferred technical solution of the present invention, the three-dimensional virtual anatomy and full-process visualization backtracking module constructs a three-dimensional gastrointestinal model based on human anatomical data and performs real-time registration with ultrasound simulation images and tactile feedback data, so that the position of the nasoenteric tube in the three-dimensional model corresponds one-to-one with the imaging position in the ultrasound image.

[0019] As a preferred technical solution of the present invention, the three-dimensional virtual anatomy and full-process visualization backtracking module is used to automatically record the advancement trajectory, ultrasound image sequence and resistance change data within a preset time period before the failure when the catheter placement fails or an abnormal event occurs, and generate failure cause analysis results based on the data.

[0020] As a preferred technical solution of the present invention, the AI-driven multi-dimensional intelligent assessment and adaptive teaching module constructs a multi-dimensional assessment index system based on student operation data, quantifies and scores operation standardization, ultrasonic interpretation ability, risk avoidance ability and strategy adaptation ability, and automatically adjusts the training difficulty or recommends corresponding teaching and training content according to the assessment results.

[0021] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention constructs a high-fidelity biomimetic multi-state simulation module for the gastrointestinal tract, and biomimetic models the anatomical structures such as the nasal cavity, pharynx, esophagus, stomach, duodenum, and intestines in a continuous pathway. It also introduces configurable parameters for various physiological and pathological states, enabling multi-state switching and realistic reproduction of nasoenteric tube placement teaching scenarios. Compared to existing teaching models that primarily rely on static structures or single resistance, this system can simulate operational differences under different gastrointestinal functional states on the same platform. This allows trainees to gradually develop a holistic understanding of different anatomical locations and functional states during training, improving their operational adaptability and safety awareness.

[0022] 2. This invention combines intelligent tactile feedback with dynamic resistance simulation, multi-dimensional ultrasound guidance with precise positioning simulation, and three-dimensional virtual anatomical visualization. During the teaching process, it simultaneously presents the tactile feedback, ultrasound imaging effects, and the spatial relationship of the nasoenteric tube within the gastrointestinal tract. Through this multimodal collaborative approach, trainees can not only perceive the resistance to advancement and the tactile feedback of retraction, but also intuitively understand the actual path of the nasoenteric tube through ultrasound images and a three-dimensional visualization interface. This compensates for the insufficient spatial cognition caused by relying solely on ultrasound images or physical models for training, and helps improve the depth of understanding and stability of ultrasound-guided nasoenteric tube placement.

[0023] 3. This invention, by setting up an AI-driven multi-dimensional intelligent assessment and adaptive teaching module, as well as a full-cycle data management and teaching supervision module, records, analyzes, and provides feedback on the trainees' operation process throughout the entire process, realizing closed-loop teaching management from training to assessment to optimization. The system can objectively evaluate trainees' performance from multiple dimensions, such as operational standardization, ultrasound interpretation ability, risk avoidance ability, and strategy adaptation ability, and adjust subsequent training content and difficulty accordingly, reducing reliance on single subjective evaluations and improving the pertinence and consistency of teaching assessments. It is suitable for various application scenarios such as medical school teaching, hospital standardized training, and skills assessment. Attached Figure Description

[0024] Fig. 1 This is a system block diagram of the present invention; Fig. 2 This is a diagram showing the composition of the high-fidelity biomimetic gastrointestinal multi-state simulation module of the present invention; Fig. 3 This is a diagram illustrating the composition of the physiological / pathological state parameter configuration unit of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the following description is provided in conjunction with embodiments and appendices. Figs. 1-3 The present invention will be further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0026] Example 1: In this example, the ultrasound-guided nasoenteric tube placement teaching simulation system is deployed in a teaching and training venue. The system includes a teaching model, a 3D virtual anatomy and simulation module, an interactive teaching and assessment module, and a system data recording and reporting module. After the system is started, the control program uniformly schedules each module to enter standby mode. Teachers or students select a training scenario and start the teaching process through the operating terminal.

[0027] At the beginning of the teaching phase, the teaching model first loads the scene and completes the state configuration of the biomimetic whole gastrointestinal system module. The biomimetic whole gastrointestinal system module is used to construct a 1:1 scale continuous anatomical pathway model, covering the entire structure of the nasal cavity, pharynx, esophagus, stomach, duodenum, jejunum, colon, and rectum. The preferred dimensions are: esophagus length 25-30cm, diameter 2.0-2.5cm; stomach capacity 1000-1500ml, stomach wall thickness 3-5mm; duodenum length 20-25cm, diameter 1.5-2.0cm; jejunum length 200-250cm, diameter 1.2-1.5cm; colon length 120-150cm, diameter 1.5-2.0cm; rectum length 12-15cm, diameter 1.8-2.2cm. The overall dimensional error is preferably no more than ±2%. In terms of materials and feel, medical-grade silicone can be used for the nasal cavity / pharynx, with Shore hardness controlled at 30-35° to simulate the soft feel of the mucous membrane. Elastic polyurethane can be used for the esophagus, with Shore hardness controlled at 40-45° to reflect physiological compliance. Biomimetic elastomers can be used for the stomach / intestinal segment, with Shore hardness controlled at 35-40° to simulate peristaltic contraction characteristics. The model surface can replicate microstructures such as mucosal folds and pyloric sphincter, with texture accuracy preferably ≤0.1mm, thus providing a clinically close anatomical basis for nasoenteric tube propulsion and positioning training.

[0028] In this embodiment, the biomimetic whole gastrointestinal system module supports pathway and parameter configuration under different gastrointestinal functional states to simulate different clinical difficulties. The system can preset multiple basic state databases, such as normal gastrointestinal function (peristalsis frequency 3-5 times / minute, propulsion resistance coefficient 0.8-1.0, regression probability 10%-15%, gastric emptying time 2-3 hours), gastroesophageal reflux (spontine tone reduced by 30%-50%, reflux frequency 2-3 times / 10 minutes, reflux simulation fluid pH 1.5-2.5, overflow probability 60%-70%, resistance coefficient 0.9-1.1), insufficient gastric motility (peristalsis frequency 1-2 times / minute, intragastric pressure 15-20 cmH2O, propulsion resistance coefficient 1.1-1.3, regression probability 25%-30%), impaired gastric emptying (simulated residual gastric fluid volume 200-300 ml, peristalsis frequency ≤ 1 time / minute, pyloric opening amplitude reduced by about 50%, pyloric passage resistance increased by 40%-60%), and gastroparesis (no spontaneous peristalsis, intragastric pressure 25-30 cmH2O). H2O (propulsion resistance coefficient 1.4-1.6, retraction probability 40%-60%, retraction distance preferably 1.5-2.0cm). Furthermore, the system offers customizable extension functions, allowing teachers to add pathological states (such as intestinal adhesions, pyloric obstruction, intestinal inflammation and stenosis, etc.) according to teaching objectives, and configure parameters such as peristalsis frequency, resistance coefficient, lumen diameter reduction ratio (e.g., 5%-50%), and sphincter tone, thereby generating personalized training scenarios. To ensure consistency across multiple modules, these state parameters can be used as unified inputs, linking the tactile feedback and resistance simulation modules as well as the ultrasound guidance and positioning modules. For example, when "lumen diameter is reduced by 30%", the tactile resistance and ultrasound display area change synchronously, thus avoiding teaching deviations caused by "inconsistency between feel and image".

[0029] During the insertion of the nasoenteric tube, the tactile feedback and resistance simulation module intervenes in real time. This module dynamically simulates the propulsion resistance, rebound, and retraction behavior based on the anatomical segment of the nasoenteric tube and the differences in gastrointestinal function, and outputs tactile feedback to the trainee through a tactile actuator. Preferably, the system can establish segmented resistance parameters: frictional resistance of the nasal cavity-pharynx segment 0.8-1.2N, turning resistance at the pharyngeal bend 1.0-1.3N, and the frictional resistance can increase by 10%-20% with the simulated amount of nasal secretions (e.g., 0-5ml); propulsion resistance of the esophagus segment 0.3-0.6N, and periodic resistance fluctuations caused by peristalsis can be superimposed (amplitude ±0.1N, period 3-5 seconds); and coiling and rebound resistance of the gastric segment 0.5-0.9N, with a coiling probability of 20%-30% under normal conditions. In cases of insufficient gastric motility, the resistance can be increased to 50%-60%, with a rebound force of 0.3-0.5N. For the pyloric segment, a breakthrough resistance of 1.3-1.8N can be set, forming a step-like resistance change of "blockage-breakthrough." In cases of gastroparesis, the breakthrough resistance can be increased to 2.0-2.3N. The basic resistance of the intestinal segment can be set to 1.0-1.5N. When stenosis is present, it can be increased synchronously according to the stenosis ratio (e.g., resistance of 2.0-2.5N when stenosis is 50%). For the colonic segment, resistance fluctuations caused by folds can be superimposed (amplitude ±0.2N).

[0030] Simultaneously, the tactile feedback and resistance simulation module can simulate the push-release-retreat phenomenon. For example, after every 3-5 cm of push, a 1-2 cm retreat occurs upon release, with a retreat speed of 0.5-1.0 cm / s. The retreat probability can be adjusted according to the pathological state (e.g., 10%-15% in normal condition, 40%-60% in gastroparesis), to train trainees in force and rhythm control at key points. To enhance the safety training effect, the system can also set a safety threshold (e.g., pushing force exceeding 2.5N). When the threshold is exceeded, the tactile resistance increases sharply (e.g., by 50%), triggering an audio-visual prompt and recording the event as a risky operation for subsequent evaluation.

[0031] During the simultaneous propulsion and tactile feedback process, the ultrasound guidance and positioning module continuously generates simulated ultrasound images to train trainees to determine the location and course of the nasoenteric tube under ultrasound conditions. This module can cover basic imaging areas (such as the inverted triangle of the esophagus, fundus, body, antrum, and horizontal segment of the duodenum) and can be extended to areas such as the upper jejunum, left colic flexure, and upper rectum. The clarity of the display can be set in gradients with depth. The nasoenteric tube can appear as a continuous hyperechoic band (preferably 2.0-2.5 mm in diameter) in the ultrasound image, and a threshold for the grayscale difference between the tube wall and lumen (e.g., ≥30) and slight acoustic shadowing features (1-2 mm in length) can be set to approximate clinical manifestations. To improve training adaptability, the ultrasound guidance and positioning module offers adjustable scanning angles and parameters, such as supporting longitudinal, transverse, and multiple oblique angles with step-wise adjustments within a 0°-180° range. It supports setting parameters such as probe frequency (e.g., 3.5-7.5MHz), gain (e.g., 20-60dB), depth (e.g., 3-10cm), and focal point, and introduces pathologically relevant noise and artifacts (e.g., salt-and-pepper noise, specular artifacts, reverberation artifacts) to train trainees' interpretation and error correction abilities. The module also provides positioning assistance prompts; when the selected window position cannot cover the tube, it provides a prompt message guiding the trainee to switch to a more suitable scanning window position to complete the positioning judgment.

[0032] During and after the operation, the 3D virtual anatomy and simulation module works in conjunction with the teaching model to synchronously display the three-dimensional position of the nasoenteric tube in the biomimetic pathway, and provides a visual playback function after the operation. In this embodiment, the module can construct a three-dimensional gastrointestinal tract model based on high-precision anatomical data and achieve size matching with the physical biomimetic model; it supports display modes such as transparency, layered display, and local magnification, so that teachers can explain the spatial relationships of key areas such as the pylorus and stenosis. The system can synchronously record the nasoenteric tube's propulsion trajectory (e.g., accuracy 0.1cm), ultrasound scanning trajectory, and propulsion force / resistance change curve (e.g., sampling frequency 100Hz), and supports multi-view playback (student's perspective, overall path perspective, ultrasound perspective, and three-dimensional anatomical perspective). During playback, key event nodes (such as entering the esophagus, passing through the pylorus, reaching the jejunum, etc.) and error events (such as incorrect window selection, propulsion force exceeding the threshold, inability to pass through the pylorus, etc.) are automatically marked, so that students can review and teachers can comment.

[0033] After training, the interactive teaching and assessment module provides process evaluation and feedback on trainees' operations. This module includes a teaching record module and a multimodal interactive teaching module. The teaching record module records data such as trainee information, training scenario, number of operations, operation time, depth of advancement, and error type and frequency. It can also record process problems such as "advance force exceeding the threshold," "frequent retreat," and "inappropriate window selection." The multimodal interactive teaching module is used to conduct interactive training under different gastrointestinal functional states. It guides trainees to think about operations and solve problems through prompts, case comparisons, and step-by-step exercises.

[0034] To achieve objective evaluation, this embodiment can establish a multi-dimensional scoring index system. For example, operational standardization, ultrasonic interpretation ability, risk avoidance ability, and strategy adaptation ability can be used as evaluation dimensions. Indicators such as stability of advancement speed, rationality of window selection, positioning deviation, performance at key nodes, and number of risk events can be quantitatively scored. It should be noted that the scoring calculation can be implemented using a rule-based model or a machine learning model (such as a recognition and scoring model trained based on historical standard operation samples). Regardless of the method used, the goal is to transform the trainee's operational performance into comparable and traceable evaluation results and output targeted training suggestions.

[0035] Finally, the system data recording and reporting module records, analyzes, and generates teaching reports based on the teaching process and evaluation results. This module includes a teaching system feedback module and a system operation recording module. The teaching system feedback module summarizes single training reports and periodic training reports, outputs overall scores, score distributions for each indicator, statistics on common errors, and improvement suggestions, and can generate learning growth curves for teaching supervision. The system operation recording module records system usage and teacher-side operation information to support teaching management and quality tracking. Reports can be exported to common document formats according to teaching needs and can include 3D playback screenshots, typical ultrasound image examples, and explanations of key event nodes, thus realizing a complete teaching process.

[0036] As can be seen from this embodiment, the ultrasound-guided nasoenteric tube placement teaching simulation system of the present invention achieves collaborative simulation of anatomical pathways, multi-state gastrointestinal function, tactile resistance and retraction phenomena, ultrasound-guided positioning, and three-dimensional playback evaluation without relying on real patients. It can improve trainees' understanding of the nasoenteric tube placement path and key nodes, enhance their operational tactile control and ultrasound interpretation capabilities, and form a traceable teaching feedback mechanism through data recording and reporting. It is suitable for application scenarios such as medical school teaching, hospital standardized training, and skills assessment.

[0037] Example 2: When the ultrasound-guided nasoenteric tube placement teaching simulation system of the present invention is running, the system control unit uniformly schedules the high-fidelity bionic gastrointestinal multi-state simulation module, the intelligent tactile feedback and dynamic resistance simulation module, the multi-dimensional ultrasound guidance and precise positioning simulation module, the three-dimensional virtual anatomy and full-process visualization backtracking module, the AI-driven multi-dimensional intelligent assessment and adaptive teaching module, and the full-cycle data management and teaching supervision module, so that each module can run synchronously and share data in the same teaching scenario.

[0038] In its implementation, the system first generates corresponding teaching scenarios using a high-fidelity biomimetic gastrointestinal multi-state simulation module. This module includes biomimetic anatomical structure units and physiological / pathological state parameter configuration units. The biomimetic anatomical structure units are used to construct biomimetic solid models of the nasal cavity, pharynx, esophagus, stomach, duodenum, jejunum, colon, and rectum, which are consistent with human anatomical proportions, and preset continuous gastrointestinal pathway coordinates x in the models.

[0039] The physiological / pathological state parameter configuration unit is used to parameterize the gastrointestinal functional state under different teaching scenarios. The system abstracts the overall gastrointestinal state into a state parameter vector: ; in, This indicates the frequency of gastrointestinal motility, measured in cycles per minute. Indicates location along the gastrointestinal pathway Effective lumen diameter at the location; This represents the equivalent elastic modulus of the gastrointestinal wall at the corresponding location; Indicates the equivalent pressure within the stomach; This represents the retraction ratio when the nasoenteric tube is released after advancement. The state parameter vector... As the basic input parameters for the entire system, they are transmitted in real time to subsequent modules for driving resistance calculation, ultrasonic simulation, and teaching evaluation.

[0040] During the nasoenteric tube insertion procedure, the intelligent tactile feedback and dynamic resistance simulation module uses the aforementioned state parameter vector. The module calculates and outputs the corresponding propulsion resistance and tactile feedback based on the real-time position of the nasoenteric tube within the biomimetic model. Internally, this module includes a segmented resistance calculation unit and a propulsion-release-retraction behavior simulation unit. ,time The total propulsive resistance is determined by the following formula: ; in, Total thrust resistance; This is the frictional resistance term; This is the term representing the resistance to elastic deformation of the gastrointestinal wall; This includes terms related to intragastric pressure and structural resistance. The frictional resistance term is calculated by the segmented resistance calculation unit in the following manner: ; in, For position The equivalent friction coefficient at a point is determined by the type of anatomical segment and its state parameters. Decide; This represents the normal force between the nasoenteric tube and the gastrointestinal wall. The elastic deformation resistance term reflects factors such as luminal narrowing and changes in gastrointestinal wall compliance; its calculation formula is as follows: ; in, This is the equivalent elastic modulus of the gastrointestinal wall in the state parameter vector; This represents the radial compression between the outer diameter of the nasoenteric tube and the effective lumen radius at the current location. Pressure and structural resistance terms are introduced in the following form: ; in, This is the pressure-resistance conversion factor; This is the equivalent pressure within the stomach; For the pylorus or other high-resistivity structural regions; This is an indicator function.

[0041] When the trainee completes one push and releases, the simulation unit for the push-release-reverse behavior follows the reversal ratio coefficient in the state parameter vector. Calculate the retraction distance of the nasoenteric tube: ; in, This is the backtracking distance; This represents the distance traveled in the previous advance. The retraction speed is further determined by the following formula: ; in, This refers to the rollback speed; A rollback time window is set for the system. The rollback result is fed back to the trainee through the tactile actuator and written into the teaching evaluation data pool.

[0042] While the nasoenteric tube is advanced and tactile feedback is performed simultaneously, a multi-dimensional ultrasound-guided and precisely positioned simulation module generates corresponding ultrasound simulation images based on the spatial position of the nasoenteric tube within the biomimetic model. This module includes an ultrasound imaging generation unit and a window level and artifact simulation unit. The spatial position of the nasoenteric tube in the world coordinate system of the gastrointestinal model is represented as follows: ; in, This represents the three-dimensional spatial position vector of the anterior end of the nasoenteric tube in the world coordinate system. This represents the coordinate components of the anterior end of the nasoenteric canal along the left-right direction in the three-dimensional virtual anatomical model. This represents the coordinate components of the anterior-posterior direction of the nasoenteric canal in the three-dimensional virtual anatomical model. This represents the coordinate components of the anterior end of the nasoenteric canal along the vertical direction in the three-dimensional virtual anatomical model. This indicates the current time during the nasoenteric tube insertion procedure.

[0043] The system maps the transformation matrix obtained through spatial calibration to the ultrasound imaging coordinate system: ; in, This is the transformation matrix from the world coordinate system to the ultrasonic coordinate system; This indicates the corresponding location of the nasoenteric canal in the ultrasound image.

[0044] The ultrasound imaging unit generates images based on the movement speed of the nasoenteric canal. Introducing a high-echo tail effect, its length is defined as: ; in, The length of the hyperechoic tail in the ultrasound image; This represents the imaging tailing coefficient. The window level and artifact simulation unit introduces gas artifacts, reverberation artifacts, or noise interference based on the relevant parameters in the state parameter vector G, to train trainees' ultrasound interpretation skills.

[0045] During the teaching process and after the operation, the 3D virtual anatomy and full-process visualization retrospective module integrates the spatial trajectory of the nasoenteric tube, tactile data and ultrasound images.

[0046] This module includes a 3D mapping display unit and an operation backtracking analysis unit. The system performs discrete sampling of the operation process to form a data set: ; in, For the first Each sampling time, This represents the number of sampling points. In the event of an anomaly or tube placement failure, the operation backtracking analysis unit calculates the average resistance based on the aforementioned data set. With maximum resistance Furthermore, by combining the ultrasound window hit rate, the causes of failure are classified and analyzed, thereby intuitively presenting the location and cause of the problem in the three-dimensional virtual anatomy interface.

[0047] During the teaching evaluation phase, the AI-driven multi-dimensional intelligent assessment and adaptive teaching module quantitatively analyzes students' performance. This module includes an indicator calculation unit and an adaptive teaching decision-making unit.

[0048] The system calculates the operational standardization score based on the mechanical data, ultrasonic interpretation data, and anomaly handling behavior during the operation. Ultrasound interpretation ability score Risk aversion ability score and strategy adaptation score The overall score is obtained through the following weighted model: ; in, For comprehensive scoring; These are the weight coefficients for each dimension, and the sum of the weights is 1.

[0049] The adaptive teaching decision unit automatically adjusts the difficulty parameters of subsequent training scenarios based on the comprehensive scoring results and pushes targeted training content to trainees.

[0050] Finally, the full-cycle data management and teaching supervision module uniformly stores and manages student information, training records, evaluation results, and operation playback data, and generates teaching reports for teacher supervision and teaching quality evaluation. Through the above modular collaborative operation, this invention achieves a complete technical closed loop within a single system, from teaching scenario construction, operation simulation, guidance and feedback to evaluation optimization.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A teaching simulation system for ultrasound-guided nasoenteric tube placement, characterized in that, The system includes: The high-fidelity bionic gastrointestinal multi-state simulation module is used to construct bionic solid models of the nasal cavity, pharynx, esophagus, stomach, duodenum, jejunum, colon and rectum that are consistent with human proportions, and supports parameterized configuration of various physiological and pathological states. The intelligent tactile feedback and dynamic resistance simulation module is used to output the corresponding propulsion resistance, rebound force and tactile feedback in real time according to the different anatomical segments of the bionic gastrointestinal model and the physiological / pathological state parameters during the propulsion of the nasoenteric tube. The multi-dimensional ultrasound guidance and positioning precision simulation module is used to simulate the ultrasound scanning process, generate ultrasound simulation images that correspond in real time to the actual position of the nasoenteric canal, and support multi-window and multi-angle guidance and positioning training. The 3D virtual anatomy and full-process visualization and backtracking module is used to display the entire process of nasoenteric tube insertion in 3D visualization, and to replay and analyze the insertion path, key nodes and abnormal events after the operation is completed or fails. AI-driven multi-dimensional intelligent assessment and adaptive teaching module is used to quantitatively assess students' operation process, ultrasound interpretation, risk avoidance and strategy selection, and generate personalized teaching feedback and training plans. The full-cycle data management and teaching supervision module is used to uniformly manage student information, training data, evaluation results and teaching records and generate teaching reports; Each module interacts and coordinates with the system control unit.

2. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 1, characterized in that, The high-fidelity biomimetic gastrointestinal multi-state simulation module includes an anatomical structure biomimetic unit and a physiological / pathological state parameter configuration unit. The anatomical structure biomimetic unit constructs the entire gastrointestinal tract structure according to the proportions of human anatomy, with a size error of no more than ±2%. The physiological / pathological state parameter configuration unit is used to set the gastrointestinal peristalsis frequency, lumen diameter, propulsion resistance coefficient, retraction probability, and sphincter tension parameters.

3. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 2, characterized in that, The physiological / pathological state parameter configuration unit includes at least the following basic states: It can simulate normal gastrointestinal function, gastroesophageal reflux, insufficient gastric motility, impaired gastric emptying, and gastroparesis, and supports user-defined extended pathological states to simulate scenarios such as intestinal stenosis, pyloric obstruction, or intestinal inflammation.

4. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 1, characterized in that, The intelligent tactile feedback and dynamic resistance simulation module adopts a segmented resistance simulation method, setting different basic resistance ranges for the nasal cavity-pharynx segment, esophagus segment, stomach segment, pyloric segment and intestinal segment, and dynamically adjusting the resistance magnitude and fluctuation characteristics according to the physiological / pathological state parameters.

5. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 4, characterized in that, The intelligent tactile feedback and dynamic resistance simulation module includes an advance-release-retreat behavior model, which simulates the retraction behavior of the tube after each preset distance of advancement, and adjusts the retraction distance, retraction speed and retraction probability according to different pathological states.

6. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 1, characterized in that, The multi-dimensional ultrasound-guided and precise positioning simulation module supports ultrasound simulation imaging of the inverted triangle of the esophagus, the fundus of the stomach, the body of the stomach, the antrum of the stomach, the horizontal segment of the duodenum, the upper segment of the jejunum, and the colon. By adjusting the probe frequency, gain, depth, and scanning angle, it can simulate the imaging effects under different ultrasound equipment and operating conditions.

7. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 6, characterized in that, The multi-dimensional ultrasound guidance and positioning precision simulation module also includes an ultrasound noise and artifact simulation unit, which is used to introduce ultrasound artifacts related to gastrointestinal gas, tissue interfaces and pathological conditions, in order to train trainees' ability to interpret ultrasound and identify misjudgments.

8. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 1, characterized in that, The three-dimensional virtual anatomy and full-process visualization backtracking module constructs a three-dimensional gastrointestinal model based on human anatomical data and performs real-time registration with ultrasound simulation images and tactile feedback data, so that the position of the nasoenteric tube in the three-dimensional model corresponds one-to-one with the imaging position in the ultrasound image.

9. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 8, characterized in that, The three-dimensional virtual anatomy and full-process visualization backtracking module is used to automatically record the advancement trajectory, ultrasound image sequence and resistance change data within a preset time period before the failure when catheter placement fails or an abnormal event occurs, and generate failure cause analysis results based on the data.

10. The ultrasound-guided nasoenteric tube placement teaching simulation system according to claim 1, characterized in that, The AI-driven multi-dimensional intelligent assessment and adaptive teaching module constructs a multi-dimensional assessment index system based on student operation data, quantifies and scores operational standardization, ultrasound interpretation ability, risk avoidance ability, and strategy adaptation ability, and automatically adjusts the training difficulty or recommends corresponding teaching and training content based on the assessment results.

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