A blood vessel quality assessment method applied to a high-pressure injector

Abstract

The application provides a blood vessel quality evaluation method applied to a high-pressure injector, which comprises a test injection stage, pressure information of a syringe or a pipeline is collected in real time when the high-pressure injector executes the stage; a motor adaptive closed-loop adjustment algorithm is used to calculate a motor rotating speed according to the collected pressure information, and an injection rate is automatically adjusted to ensure that the pressure of the syringe or the pipeline in the test injection stage does not exceed a pressure protection threshold of the high-pressure injector; injection data obtained in the test injection process is imported into a database, a current patient blood vessel quality grade is calculated through a contrast agent nuclear speed algorithm, and maximum injection rate data suitable for the contrast agent is generated. The application improves the accuracy and efficiency of blood vessel quality evaluation by detecting the injection pressure in real time and automatically adjusting the injection rate, so that the failure of enhanced imaging caused by improper injection rate parameter setting is avoided.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a method for assessing vascular quality in a high-pressure injector. It is mainly used to precisely control the injection speed, dosage, and timing of contrast agents (such as iodine and gadolinium) to optimize image quality in CT and MR imaging. Background Technology

[0002] A high-pressure injector delivers contrast agent into a patient's blood vessels at a predetermined rate and dosage via a vein to improve image quality in CT or MR imaging. Because the quality of blood vessels varies greatly among patients requiring contrast agent injection—for example, younger patients have more flexible blood vessels, allowing for more flexible injection rates—older patients have less vascular flexibility. If a higher injection rate is used, the high-pressure injector is more likely to detect excessive pressure and trigger its pressure protection mechanism, prematurely ending the injection. In this case, the contrast agent is not fully delivered into the patient's blood vessel, resulting in a failed injection.

[0003] Currently, doctors use a saline injection test to assess a patient's vascular quality. Before injecting the contrast agent, based on clinical experience and the patient's condition (age, weight, etc.), the vascular quality is pre-assessed. Then, a small amount (10-20 ml) of saline is injected at the assessed injection rate. If the injection is successful (high-pressure injection does not trigger a pressure alarm or the detected pressure is too low), the patient's vascular quality and the appropriate contrast agent injection rate can be roughly assessed. If the doctor lacks clinical experience, multiple injections of saline at different rates may be necessary to complete the vascular quality assessment. Furthermore, an inappropriate injection rate may reduce the accuracy of the assessment, ultimately affecting the image quality of the imaging equipment. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a vascular quality assessment method applied to high-pressure injectors. By real-time detection of injection pressure and automatic adjustment of injection rate, the accuracy and efficiency of vascular quality assessment are improved, thereby avoiding contrast-enhanced angiography failure caused by inappropriate injection rate parameter settings.

[0005] The present invention achieves the above objectives through the following technical solutions: A method for assessing vascular quality in high-pressure injectors, comprising: Set up a trial injection phase, and collect pressure information of the injection syringe or tubing in real time when the high-pressure injector performs this phase; Based on the collected pressure information, the motor rotation speed is calculated using an adaptive closed-loop adjustment algorithm, and the injection rate is automatically adjusted to ensure that the pressure of the syringe or tubing does not exceed the pressure protection threshold of the high-pressure injector during the trial injection phase. The injection data obtained during the trial injection is imported into the database, and the current vascular quality grade of the patient is calculated using the contrast agent nuclear rate algorithm. Generate data on the maximum injection rate suitable for the contrast agent.

[0006] According to the present invention, a method for assessing vascular quality in a high-pressure injector is provided, wherein pressure information of the injection syringe or tubing is acquired through the following pressure acquisition method: A miniature thin-film piezoresistive sensor is used, which is directly attached to the end face of the syringe plunger; The pressure sensor is physically connected to the input shaft of the lead screw in the transmission structure. When the lead screw pushes the syringe piston forward, the force of the syringe piston is transmitted to the pressure sensor through the lead screw.

[0007] According to the present invention, a method for assessing vascular quality in a high-pressure injector is provided. Based on the collected real-time pressure data, a dynamic mapping relationship between the pressure change rate ΔP / Δt and the motor speed ω is established, expressed as the following formula:

[0008] in, For the controller at time step The output, For the controller at time step The output, For time steps Pressure error, For time steps Pressure error The cumulative sum of errors, , , To adaptively adjust the parameters, a fuzzy logic controller dynamically adjusts them based on the current pressure fluctuation range. Based on the detected change in resistance R of the pressure sensor, the pressure P inside the syringe is calculated in real time using a lookup table method. actual The corrected formula is:

[0009] in, Based on pressure, This is the resistance compensation coefficient.

[0010] According to the present invention, a method for assessing vascular quality in a high-pressure injector integrates an embedded database module in the main control board and uses an SQLite engine to store the following data in real time during the trial injection phase: Time series data: Pressure sampling values, actual injection rate of trial injections, and the relationship between pressure and injection rate; Event tagging data: injection start time, pressure over-limit alarm time, pipeline resistance change time, each event is accompanied by a timestamp; Patient characteristic data: age, weight, gender, indwelling needle diameter, contrast agent type and concentration, are entered and encrypted by the operating terminal before injection.

[0011] According to the present invention, a method for assessing vascular quality in a high-pressure injector is provided. All injection data and calculation results are encrypted with AES-256 and stored in a database module, which supports querying historical data by inputting the patient ID through an operating terminal. The database automatically generates a CRC32 data integrity check code daily. If a check failure is detected, the data is restored from the backup storage area, which retains the injection records for the most recent 7 days.

[0012] According to the present invention, a method for assessing vascular quality in a high-pressure injector is provided, which calculates vascular quality based on acquired injection data using the following contrast agent nuclear rate algorithm formula:

[0013] in, This is a reference value for a saline injection test. This is a reference value for a saline injection test. 、 、 Clinical calibration coefficient, These represent the changes in injection rate and injection pressure per unit time obtained during the trial injection, respectively.

[0014] according to Q vessel The values ​​are used to classify the quality of blood vessels and are displayed intuitively through a dialog box on an LCD screen.

[0015] According to the present invention, a method for assessing vascular quality in a high-pressure injector is provided, wherein a concentration-viscosity comparison table of different types of contrast agents is pre-stored in the main control board, and a real-time viscosity calculation model is established through polynomial fitting:

[0016] in, The viscosity of the contrast agent at concentration C. For pure solvent viscosity, These are the fitting coefficients. This refers to the concentration of the contrast agent; When a contrast agent type switch is detected, the coefficients of the corresponding model are automatically called to calculate the viscosity and updated to the real-time parameter library.

[0017] According to the present invention, a method for assessing vascular quality in a high-pressure injector is provided to calculate the maximum permissible injection rate. V max : + Q vessel。

[0018] in, , 2 represents the calibration parameters used in clinical validation. P safe When setting injection plans for users, the pressure protection thresholds are defined, where V0 and P0 represent the injection rate and pressure during the injection process. The concentration of physiological saline during the test injection. Q vessel This refers to the vascular quality index. μ ( C () represents the current viscosity of the contrast agent.

[0019] Therefore, compared with the prior art, the vascular quality assessment method proposed in this invention has the following beneficial effects: 1. This invention collects dynamic pressure and rate data of the injection syringe or tubing in real time during trial injections. Utilizing a closed-loop control algorithm, it automatically adjusts the injection rate based on pressure levels, avoiding errors from subjective judgment. This allows for a more accurate reflection of the patient's vascular capacity under current injection conditions, significantly improving the precision of vascular quality assessment. For example, for patients with weak vascular resilience, the system can promptly detect pressure changes and reduce the injection rate, ensuring successful trial injections and providing a more reliable basis for subsequent contrast agent injections.

[0020] 2. This invention calculates the maximum appropriate contrast agent injection rate for the current patient based on data obtained during trial injections, combined with a contrast agent nuclear rate algorithm, and recommends this rate to the physician. The physician can set injection parameters according to the system's recommended rate, avoiding injection failures due to improper rate settings. Furthermore, this invention displays a warning message if the calculated maximum contrast agent injection rate is less than a certain amount set by the physician; the injection can only continue after the physician's confirmation, further improving the safety and success rate of the injection.

[0021] 3. This invention automatically adjusts the injection rate by monitoring the injection pressure in real time and using a closed-loop control algorithm. This ensures that the pressure of the syringe or tubing does not exceed the pressure protection threshold of the high-pressure injector during the trial injection phase, effectively preventing damage to the patient's blood vessels due to excessive pressure and ensuring the safety of the medical process. For example, for patients with fragile blood vessels, the system can promptly adjust the injection rate to a safe range to prevent serious complications such as vascular rupture.

[0022] 4. The specific trial injection stage designed in this invention can obtain sufficient data through a single trial injection process, and use algorithms to quickly calculate the maximum contrast agent injection rate applicable to the patient. Injection parameters can be quickly set according to the system's recommended results, reducing the number of trial injections and evaluation time, and greatly improving medical efficiency.

[0023] In summary, the vascular quality assessment method for high-pressure injectors provided by this invention has the advantages of improving assessment accuracy, increasing injection success rate, enhancing safety, improving medical efficiency, and promoting data accumulation and analysis. It is of great significance for improving the quality and efficiency of medical imaging examinations.

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0025] Figure 1 This is a flowchart of an embodiment of a vascular quality assessment method for high-pressure injectors according to the present invention.

[0026] Figure 2 This is a schematic diagram of the trial injection stage in an embodiment of a vascular quality assessment method for high-pressure injectors according to the present invention.

[0027] Figure 3 This is a schematic diagram illustrating the operating principle of a high-pressure injector in an embodiment of a vascular quality assessment method applied to a high-pressure injector according to the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0029] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0030] See Figures 1 to 3 This embodiment provides a method for assessing vascular quality in a high-pressure injector, comprising: Step S1: Set up the trial injection stage. When the high-pressure injector performs this stage, the pressure information of the injection syringe or tubing is collected in real time. Step S2: Based on the collected pressure information, the motor rotation speed is calculated using the motor adaptive closed-loop adjustment algorithm, and the injection rate is automatically adjusted to ensure that the pressure of the syringe or tubing does not exceed the pressure protection threshold of the high-pressure injector during the trial injection stage. Step S3: Import the injection data obtained during the trial injection into the database, and calculate the current vascular quality grade of the patient using the contrast agent nuclear rate algorithm; Step S4: Generate the maximum injection rate data applicable to the contrast agent.

[0031] In step S1 above, the pressure information of the injection syringe or tubing is collected through the following pressure acquisition method: A miniature thin-film piezoresistive sensor is used, which is directly attached to the end face of the syringe plunger. The sensor has a range of 0-50 MPa, a resolution of ≤0.01 MPa, and a response time of ≤1 ms. Thermally conductive silicone grease is used to fill the gap between the sensor and the plunger to ensure uniform pressure transmission.

[0032] The pressure sensor is physically connected to the input shaft of the lead screw in the transmission structure. When the lead screw pushes the syringe piston forward, the force of the syringe piston is transmitted to the pressure sensor through the lead screw.

[0033] In step S2 above, based on the collected real-time pressure data, a dynamic mapping relationship between the pressure change rate ΔP / Δt and the motor speed ω is established, expressed as the following formula:

[0034] in, For the controller at time step The output, For the controller at time step The output, For time step Pressure error, For time step Pressure error The cumulative sum of errors, , , To adaptively adjust the parameters, a fuzzy logic controller dynamically adjusts them based on the current pressure fluctuation range. Based on the detected change in resistance R of the pressure sensor, the pressure P inside the syringe is calculated in real time using a lookup table method. actual The corrected formula is:

[0035] in, Based on pressure, This is the resistance compensation coefficient.

[0036] In step S3 above, an embedded database module is integrated into the main control board, using the SQLite engine to store the following data during the trial injection phase in real time: Time series data: pressure sampling values, actual injection rates of trial injections, and the relationship between pressure and injection rate; Event tagging data: injection start time, pressure over-limit alarm time, pipeline resistance change time, each event is accompanied by a timestamp; Patient characteristic data: age, weight, gender, indwelling needle diameter, contrast agent type and concentration, are entered and encrypted by the operating terminal before injection.

[0037] In this embodiment, all injection data and calculation results are encrypted using AES-256 and stored in the database module, supporting historical data queries via inputting the patient ID on the operating terminal; The database automatically generates a CRC32 data integrity check code daily. If a check failure is detected, the data is restored from the backup storage area, which retains the injection records for the most recent 7 days.

[0038] In step S3 above, based on the acquired injection data, the vessel mass is calculated using the following contrast agent nuclear rate algorithm formula:

[0039] in, This is a reference value for a saline injection test. This is a reference value for a saline injection test. 、 、 Clinical calibration coefficient, These represent the changes in injection rate and injection pressure per unit time obtained during the trial injection, respectively.

[0040] according to Q vesselThe values ​​are used to classify the quality of blood vessels and are displayed intuitively through a dialog box on an LCD screen.

[0041] In step S4 above, a concentration-viscosity comparison table for different types of contrast agents is pre-stored in the main control board, and a real-time viscosity calculation model is established through polynomial fitting:

[0042] in, The viscosity of the contrast agent at concentration C. For pure solvent viscosity, These are the fitting coefficients. This refers to the concentration of the contrast agent; When a contrast agent type switch is detected, the coefficients of the corresponding model are automatically called to calculate the viscosity and updated to the real-time parameter library.

[0043] Calculate the maximum permissible injection rate V max .

[0044] + Q vessel。

[0045] in, , 2 represents the calibration parameters used in clinical validation. P safe When setting injection plans for users, the pressure protection thresholds are defined, where V0 and P0 represent the injection rate and pressure during the injection process. The concentration of the saline solution during the test injection. Q vessel This refers to the vascular quality index. μ ( C () represents the current viscosity of the contrast agent.

[0046] In practical applications, this embodiment designs a specific trial injection phase. During this phase, the high-pressure injector collects real-time pressure information from the syringe or tubing. Based on the pressure, the device uses a motor adaptive closed-loop adjustment algorithm to calculate the motor rotation speed, thereby automatically adjusting the injection rate to ensure that the pressure in the syringe or tubing does not exceed the high-pressure injector's pressure protection threshold during the trial injection phase. Simultaneously, the system imports the injection rate and pressure data acquired during the trial injection into a database and uses an algorithm to recommend the maximum suitable injection rate for the current contrast agent to the physician for reference.

[0047] The specific steps are as follows: Installation and Preparation: Attach the syringe to the high-pressure injector and draw in saline and contrast agent, respectively. Connect and secure the injection tubing to the syringe, purge air from the syringe and tubing, and then connect the injection tubing to the patient's vein.

[0048] Setting up an injection plan: The physician sets up the injection protocol, including a trial injection phase (Phase T), a maintenance phase (Phase H), a contrast agent injection phase (Phase B), and a saline injection phase (Phase A). The trial injection phase sets the injection rate and dosage, using saline as the trial agent.

[0049] Doctors can set up injection plans, such as four stages, or more stages (depending on the doctor's needs).

[0050] The first stage is the trial injection stage (stage T). The settings for this stage include the injection rate and dosage. The trial injection drug is physiological saline.

[0051] The second stage, the maintenance stage (stage H), aims to pause the injection after the first stage is completed, allowing the doctor to determine whether to continue the injection or change the injection plan based on the trial injection results.

[0052] The third stage, the contrast agent injection stage (stage B), includes information on the injection rate and dosage.

[0053] The fourth stage, the saline injection stage (stage A), includes information on the injection rate and dosage. The goal is to deliver the contrast agent injected in stage B to the target imaging site as quickly as possible.

[0054] Execution of the trial injection plan: During the trial injection, the device collects real-time pressure information from the syringe or tubing and calculates the motor rotation speed using an adaptive closed-loop adjustment algorithm based on the pressure, automatically adjusting the injection rate. Simultaneously, the injection rate and pressure data acquired during the trial injection are imported into the contrast agent velocity database. The contrast agent velocity algorithm calculates the current patient's vascular quality grade and, combined with the contrast agent concentration information used by the doctor, calculates the maximum applicable injection rate for the contrast agent for the doctor's reference. If the calculated maximum contrast agent injection rate is less than a certain amount of the contrast agent injection rate set by the doctor, a warning message is displayed to the doctor. The injection plan can only be continued after the doctor's confirmation.

[0055] Adjusting and executing the injection plan: After adjusting the injection plan parameters based on the trial injection results, the doctor triggers the high-pressure injector to continue executing the new injection plan. The high-pressure injector executes the injection process according to the injection plan parameters and acquires injection pressure and injection rate data in real time.

[0056] Injection completion and scanning: After the injection plan is completed, the scanning image device starts scanning the image.

[0057] Regarding the method of acquiring pressure data, this embodiment uses the pressure sensor of the push rod to acquire the data, but it can also be replaced by an external sensor that monitors the pressure of the pipeline or a pressure sensor built into the injection pipeline.

[0058] Regarding the motor speed adjustment algorithm, in this embodiment, the motor speed adjustment algorithm can adopt a PID closed-loop control strategy, or other automatic closed-loop control algorithms.

[0059] Regarding the method of adjusting the injection rate, in this embodiment, the injection rate can be adjusted linearly based on the pressure threshold or by using a continuous nonlinear adjustment method.

[0060] Regarding the contrast agent maximum rate recommendation algorithm, this embodiment uses a contrast agent core rate database and a contrast agent core rate algorithm to calculate the maximum rate of contrast agent adaptation. This is a data update control algorithm with self-learning capabilities. Of course, there are also similar simplified proportional methods, such as contrast agent rate = f(x, y), where f is an equation, x is the injection rate during the saline trial injection, and y is the rotation speed and pressure during the saline trial injection.

[0061] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for assessing vascular quality in a high-pressure injector, characterized in that, include: Set up a trial injection phase, and collect pressure information of the injection syringe or tubing in real time when the high-pressure injector performs this phase; Based on the collected pressure information, the motor rotation speed is calculated using an adaptive closed-loop adjustment algorithm, and the injection rate is automatically adjusted to ensure that the pressure of the syringe or tubing does not exceed the pressure protection threshold of the high-pressure injector during the trial injection phase. The injection data obtained during the trial injection is imported into the database, and the current vascular quality grade of the patient is calculated using the contrast agent nuclear rate algorithm. Generate data on the maximum injection rate suitable for the contrast agent.

2. The method according to claim 1, characterized in that, Pressure information from the syringe or tubing is collected using the following pressure acquisition methods: A miniature thin-film piezoresistive sensor is used, which is directly attached to the end face of the syringe plunger; The pressure sensor is physically connected to the input shaft of the lead screw in the transmission structure. When the lead screw pushes the syringe piston forward, the force of the syringe piston is transmitted to the pressure sensor through the lead screw.

3. The method according to claim 1, characterized in that: Based on the collected real-time pressure data, a dynamic mapping relationship between the pressure change rate ΔP / Δt and the motor speed ω is established, expressed by the following formula: in, For the controller at time step The output, For the controller at time step The output, For time steps Pressure error, For time steps Pressure error The cumulative sum of errors, , , To adaptively adjust the parameters, a fuzzy logic controller dynamically adjusts them based on the current pressure fluctuation range. Based on the detected change in resistance R of the pressure sensor, the pressure P inside the syringe is calculated in real time using a lookup table method. actual The corrected formula is: in, Based on pressure, This is the resistance compensation coefficient.

4. The method according to claim 1, characterized in that: An embedded database module is integrated into the main control board, using the SQLite engine to store the following data in real time during the trial injection phase: Time series data: pressure sampling values, actual injection rates of trial injections, and the relationship between pressure and injection rate; Event tagging data: injection start time, pressure over-limit alarm time, pipeline resistance change time, each event is accompanied by a timestamp; Patient characteristic data: age, weight, gender, indwelling needle diameter, contrast agent type and concentration, are entered and encrypted by the operating terminal before injection.

5. The method according to claim 4, characterized in that: All injection data and calculation results are encrypted with AES-256 and stored in the database module. Historical data can be queried by entering the patient ID through the operation terminal. The database automatically generates a CRC32 data integrity check code daily. If a check failure is detected, the data is restored from the backup storage area, which retains the injection records for the most recent 7 days.

6. The method according to any one of claims 1 to 5, characterized in that: Based on the acquired injection data, vessel mass was calculated using the following contrast agent nuclear rate algorithm formula: in, This is a reference value for a saline injection test. This is a reference value for a saline injection test. 、 、 Clinical calibration coefficient, These are the changes in injection rate and injection pressure per unit time obtained during the trial injection, respectively. according to Q vessel The values ​​are used to classify the quality of blood vessels and are displayed intuitively through a dialog box on an LCD screen.

7. The method according to claim 6, characterized in that: A concentration-viscosity comparison table for different types of contrast agents is pre-stored in the main control board, and a real-time viscosity calculation model is established through polynomial fitting: in, The viscosity of the contrast agent at concentration C. For pure solvent viscosity, These are the fitting coefficients. This refers to the concentration of the contrast agent; When a contrast agent type switch is detected, the coefficients of the corresponding model are automatically called to calculate the viscosity and updated to the real-time parameter library.

8. The method according to claim 7, characterized in that: Calculate the maximum permissible injection rate V max : + Q vessel in, , 2 represents the calibration parameters used in clinical validation. P safe When setting injection plans for users, the pressure protection thresholds are defined, where V0 and P0 represent the injection rate and pressure during the injection process. The concentration of the saline solution during the test injection. Q vessel This refers to the vascular quality index. μ ( C () represents the current viscosity of the contrast agent.

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