A multi-channel urodynamic assessment system based on sacral nerve stimulation

Abstract

The application discloses a multi-channel urodynamic evaluation system based on sacral nerve stimulation. The system comprises a liquid perfusion module for perfusing liquid into the bladder through a perfusion cavity; a multi-channel signal acquisition module for acquiring bladder pressure signals through a MEMS pressure sensor in a pressure measuring cavity, acquiring abdominal pressure signals through an abdominal pressure sensor, and acquiring external urethral sphincter electromyographic signals through a ring electrode; a constant current stimulation output module for outputting bidirectional symmetric square wave pulses to the sacral nerve; a synchronous control module for triggering the multi-channel signal acquisition module to synchronously sample and output a hardware time stamp at the edge of the pulse output by the constant current stimulation output module; and a result evaluation module for obtaining a urodynamic evaluation report. The multi-channel urodynamic evaluation system integrates liquid perfusion, multi-channel synchronous acquisition and step stimulation, and realizes a precise urodynamic evaluation system.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and more specifically, to a multi-channel urodynamic assessment system based on sacral nerve stimulation. Background Technology

[0002] Urodynamic testing is an important means of assessing lower urinary tract dysfunction. By simultaneously monitoring intravesical pressure, abdominal pressure, detrusor pressure, and electromyographic activity of the external urethral sphincter, it provides objective evidence for the clinical diagnosis of diseases such as overactive bladder and detrusor-sphincter dyssynergia.

[0003] Current urodynamic devices have the following shortcomings: traditional devices only have a data acquisition function and cannot integrate controllable constant current stimulation output. Doctors can determine if a user has bladder overactivity, but cannot verify the effectiveness of sacral nerve electrical stimulation treatment preoperatively; when assessing the impact of electrical stimulation on bladder function, the urodynamic device and an independent electrical stimulator must be used separately and operated at different times. The independent operation of the two devices leads to a lack of precise alignment between stimulation and acquisition times, and the temporal relationship between stimulation and response is unclear; stimulation output relies solely on software to record the stimulation time, resulting in millisecond-level delays and an inability to accurately locate the evoked window after stimulation; the electrical stimulation current is in the milliampere range while the electromyographic signal is in the microvolt range, and the stimulation pulse generates a large electrical stimulation artifact, causing short-term amplifier saturation and making it impossible to acquire evoked electromyographic signals within the critical window after stimulation; existing systems typically only acquire single-channel electromyographic signals and cannot eliminate interference from non-target factors such as abdominal muscle contraction and user-initiated exertion through multi-point synchronous monitoring, which easily leads to misdiagnosis. Therefore, there is an urgent need for a urodynamic assessment system that integrates fluid perfusion, multi-channel signal acquisition, constant current stimulation output, synchronous control, and result evaluation. Summary of the Invention

[0004] One objective of this application is to provide a multi-channel urodynamic assessment system based on sacral nerve stimulation, which can at least solve the aforementioned technical problems in the prior art.

[0005] To achieve the above objectives, this application provides the following technical solutions.

[0006] A multi-channel urodynamic assessment system according to an embodiment of the first aspect of this application includes: a fluid infusion module for infusing fluid into the bladder through the infusion chamber of a three-lumen integrated catheter and calculating the fluid infusion volume in real time; a multi-channel signal acquisition module including a pressure acquisition unit and an electromyography (EMG) acquisition unit, wherein the pressure acquisition unit acquires bladder pressure signals through a MEMS pressure sensor in the pressure measurement chamber of the three-lumen integrated catheter and also acquires user abdominal pressure signals through an abdominal pressure sensor; and the EMG acquisition unit acquires EMG signals corresponding to the external urethral sphincter through a ring electrode disposed on the distal outer wall of the three-lumen integrated catheter; and constant current stimulation. The output module is used to output a charge-balanced bidirectional symmetrical square wave pulse to the sacral nerve via a ring electrode; the synchronization control module is used to trigger the multi-channel signal acquisition module to synchronously sample at the edge of the pulse output by the constant current stimulation output module, and to synchronously output a hardware timestamp at the moment of stimulation output; the result evaluation module is used to perform auxiliary identification of detrusor and sphincter dyssynergy based on the pressure signal and electromyographic signal obtained by synchronous sampling, and, if detrusor and sphincter dyssynergy is identified, to start the constant current stimulation output module to perform stepwise stimulation and induce electromyographic threshold recording to obtain a urodynamic evaluation report.

[0007] Optionally, the three-lumen integrated catheter includes an infusion interface, a pressure measuring interface, and an electrical interface that are respectively connected to the infusion chamber, the pressure measuring chamber, and the lead wire chamber; wherein, the infusion interface is connected to the liquid infusion module, the pressure measuring interface is connected to the pressure acquisition unit, and the electrical interface is connected to the constant current stimulation output module and the electromyography acquisition unit.

[0008] Optionally, the pressure acquisition unit is also used to calculate the detrusor pressure signal based on the bladder pressure signal and the abdominal pressure signal.

[0009] Optionally, the electromyography (EMG) acquisition unit also includes a first channel for acquiring abdominal muscle EMG signals via surface-mount electrodes, a second channel for acquiring anal sphincter EMG signals via electrodes, and a third channel for acquiring external urethral sphincter EMG signals via ring electrodes.

[0010] Optionally, the electromyography (EMG) acquisition unit adopts a differential bipolar input method and has electrode impedance detection function.

[0011] Optionally, the constant current stimulation output module includes at least one channel for isolated constant current output and has short-circuit protection, overcurrent protection, charge imbalance detection, and output abnormality alarm functions.

[0012] Optionally, the synchronization control module includes a hardware trigger synchronization unit and a hardware timestamp marking unit. The hardware trigger synchronization unit triggers the multi-channel signal acquisition module to synchronously sample at the edge of the pulse, and the hardware timestamp marking unit outputs a mark bit and writes it into the data stream at the moment of stimulus output.

[0013] Optionally, when the results evaluation module performs auxiliary identification of detrusor and sphincter dyssynergism, it simultaneously analyzes the temporal relationship between detrusor pressure and external urethral sphincter electromyography (EMG) signals to determine whether there is abnormal contraction of the external urethral sphincter during detrusor contraction. If there is paradoxical contraction of the external urethral sphincter during detrusor contraction, the results evaluation module is also used to determine the type of abnormal contraction of the external urethral sphincter based on the synchronicity of the EMG signals of the external urethral sphincter and the anal sphincter. If the abnormal contraction type of the external urethral sphincter is neurogenic, the constant current stimulation output module is activated to perform stepwise stimulation and induce EMG threshold recording; or, if the abnormal contraction type of the external urethral sphincter is localized muscular, a corresponding urodynamic assessment report is directly generated for the user.

[0014] Optionally, when performing stepwise stimulation and evoked electromyography threshold recording, the result evaluation module increases the stimulation current intensity in a stepwise manner, simultaneously records the amplitude of the evoked electromyography response at each intensity, and automatically identifies the evoked response threshold.

[0015] Optionally, the result evaluation module is also used to obtain the user's target electrical stimulation parameters based on the amplitude of the evoked electromyographic response corresponding to each step of stimulation intensity in the test results recorded by the step stimulation and evoked electromyographic threshold; the result evaluation module is also used to generate a urodynamic evaluation report corresponding to the user based on the type of abnormal contraction of the external urethral sphincter and the user's target electrical stimulation parameters.

[0016] In summary, the multi-channel urodynamic assessment system provided in this application has the following beneficial effects: First, it integrates fluid perfusion, multi-channel signal acquisition, constant current stimulation output, synchronous control, and result evaluation functions into one system, allowing verification of the user's responsiveness to sacral nerve electrical stimulation via an external catheter electrode. Second, through a hardware-triggered synchronization mechanism, it ensures precise alignment between the stimulation output time and the sampling time of all acquisition channels, providing a reliable data foundation for stimulus-response timing analysis. Third, by marking stimulation events with hardware timestamps, the timestamps are still fully preserved even during short-term amplifier saturation, allowing the back-end algorithm to accurately locate the evoked window after stimulation. Fourth, by simultaneously monitoring abdominal muscle electromyography (EMG), anal sphincter EMG, and external urethral sphincter EMG, multi-channel cross-validation is achieved, eliminating EMG artifacts introduced by the activation of non-target muscle groups. Fifth, through a step-by-step evaluation process involving detrusor and sphincter dyssynergy-assisted identification and stepwise stimulation and evoked EMG threshold recording, a complete evaluation chain from functional assessment to stimulation effect verification is realized.

[0017] Other features and advantages of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present application and, together with their description, serve to explain the principles of the present application.

[0019] Figure 1 This is a schematic diagram of the structure of a multichannel urodynamic assessment system according to an embodiment of this application; Figure 2 This is a structural schematic diagram of the hardware configuration structure of the main control module 1001 of a multichannel urodynamic assessment system 1000 according to an embodiment of this application; Figure 3 This is a schematic diagram of a multi-channel urodynamic assessment system according to an embodiment of this application in conjunction with a three-lumen integrated catheter; Reference numerals: Multichannel urodynamic assessment system 1000; Fluid perfusion module 100; Multichannel signal acquisition module 200; Pressure acquisition unit 210; Electromyography acquisition unit 220; Constant current stimulation output module 300; Synchronization control module 400; Result evaluation module 500; Three-lumen integrated catheter 600; Ring electrode 610; Perfusion interface 620; Pressure measurement interface 630; Electrical interface 640; Surface electrode 710; Anal electrode 720; Abdominal pressure sensor 730. Detailed Implementation

[0020] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0021] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0022] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0023] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0025] Implementation environment and hardware configuration

[0026] Figure 2This is a hardware configuration diagram of the main control module 1001 of the multi-channel urodynamic assessment system 1000 applicable to embodiments of the present invention. The main control module 1001 is used to control any module included in the multi-channel urodynamic assessment system to execute corresponding control steps.

[0027] like Figure 2 As shown, the main control module 1001 may include a processor 1100, a memory 1200, an interface device 1300, a display device 1400, and an input device 1500. The processor 1100 executes computer programs, which may use instruction sets based on architectures such as x86, Arm, RISC, MIPS, and SSE. The memory 1200 may include, for example, ROM (Read-Only Memory), RAM (Random Access Memory), or non-volatile memory such as a hard disk. The interface device 1300 is a physical interface, such as a USB interface or a headphone jack. The display device 1400 may be a screen, which may be a touch screen. The input device 1500 may include a keyboard, mouse, or a touch device. The multi-channel urodynamic assessment system 1000 also includes an external power supply device for powering all modules of the system.

[0028] In this embodiment, the memory 1200 of the main control module 1001 is used to store a computer program that controls the processor 1100 to operate and implement the control steps of the multichannel urodynamic assessment system according to any embodiment. Those skilled in the art can design the computer program based on the scheme disclosed in this specification. How the computer program controls the processor 1100 to operate is well known in the art and will not be described in detail here.

[0029] Those skilled in the art should understand that, although in Figure 2 The main control module 1001 is shown in the figure. The main control module 1001 of this embodiment may involve only some of the devices, or may also include other devices, which is not limited here.

[0030] System Implementation Examples

[0031] The multichannel urodynamic assessment system according to embodiments of this application is described in detail below with reference to the accompanying drawings.

[0032] like Figures 1 to 3As shown, the multi-channel urodynamic assessment system according to an embodiment of this application implements corresponding steps based on a pre-inserted three-lumen integrated catheter in the user's bladder. The three-lumen integrated catheter includes an infusion chamber, a pressure measuring chamber, and a lead wire chamber. The system includes: a liquid infusion module for infusing liquid into the bladder through the infusion chamber of the three-lumen integrated catheter and calculating the liquid infusion volume in real time; and a multi-channel signal acquisition module, including a pressure acquisition unit and an electromyography (EMG) acquisition unit. The pressure acquisition unit acquires bladder pressure signals through a MEMS pressure sensor in the pressure measuring chamber of the three-lumen integrated catheter and also acquires the user's abdominal pressure signals through an abdominal pressure sensor. The EMG acquisition unit acquires signals through a ring-shaped sensor located on the distal outer wall of the three-lumen integrated catheter. Electrode 610 acquires electromyographic signals corresponding to the external urethral sphincter; a constant current stimulation output module is used to output a charge-balanced bidirectional symmetrical square wave pulse to the sacral nerve through the ring electrode 610; a synchronization control module is used to hardware trigger the multi-channel signal acquisition module to synchronously sample at the edge of the pulse output by the constant current stimulation output module, and to synchronously output a hardware timestamp at the moment of stimulation output; a result evaluation module is used to perform auxiliary identification of detrusor and sphincter dyssynergy based on the pressure signal and electromyographic signal obtained by synchronous sampling, and when detrusor and sphincter dyssynergy is identified, the constant current stimulation output module is activated to perform stepwise stimulation and induce electromyographic threshold recording to obtain a urodynamic evaluation report.

[0033] Specifically, the three-lumen integrated catheter 600 is inserted and positioned within the user's body as follows: The tip of the catheter 600 has a smooth, hemispherical structure and is inserted through the external urethral orifice. For male users, the catheter 600 is continuously advanced until urine flows from the catheter tip, confirming that the tip has entered the bladder; at this point, the total insertion depth is approximately 20 to 22 centimeters. The catheter 600 is then slowly withdrawn, while the electromyographic (EMG) waveform of the external urethral sphincter is observed in real time via the ring electrode 610. When withdrawal is complete and a clear characteristic sphincter signal (significantly increased amplitude during contraction) is observed in the EMG signal, withdrawal is stopped, and the external portion of the catheter 600 is secured to the inner thigh. At this point, the tip of the catheter 600 is located within the bladder, and the ring electrode 610 is positioned at the external urethral sphincter. Similarly, for female users, after inserting the catheter 600 until urine flows out to confirm that the tip has entered the bladder, the initial insertion depth is approximately 7 to 9 cm. Then, it is slowly withdrawn while observing the electromyographic (EMG) signal. Retraction is stopped and the catheter is fixed when characteristic sphincter signals are observed, with a final insertion depth of approximately 5 to 6 cm. It should be noted that the above withdrawal distance values ​​are only typical reference values ​​and should not be used as the basis for fixing the insertion depth. Due to significant individual differences in urethral length among users, it is necessary to rely on the real-time EMG signal feedback acquired by the ring electrode 610 to confirm whether the ring electrode 610 is located at the external urethral sphincter; the scale markings are only for auxiliary reference. The external portion of the catheter 600 is fixed to the inner thigh with medical tape to prevent catheter displacement and loss of EMG signals.

[0034] Let's discuss this in detail below, such as Figure 2 As shown, the multi-channel urodynamic assessment system 1000 based on sacral nerve stimulation in this embodiment is implemented in conjunction with the aforementioned pre-inserted three-lumen integrated catheter 600 in the user's bladder. The catheter insertion and fixation method is as described above. It is particularly important to note that the three-lumen integrated catheter described in this application can specifically be the three-lumen integrated catheter provided in invention patent CN202611356031.X. The detailed structure of this three-lumen integrated catheter can be found in the patent specification, which is not the focus of this application and will not be repeated here. The three-lumen integrated catheter 600 may include an infusion chamber, a pressure measurement chamber, and a lead chamber. The multi-channel urodynamic assessment system 1000 in this embodiment includes a liquid infusion module 100, a multi-channel signal acquisition module 200, a constant current stimulation output module 300, a synchronization control module 400, and a result evaluation module 500.

[0035] In detail, the liquid infusion module 100 in this embodiment infuses physiological saline or other medical infusion fluids into the bladder through the infusion chamber of the three-lumen integrated catheter 600, and counts the cumulative volume of fluid injected in real time during the infusion process. Specifically, the liquid infusion module 100 in this embodiment can be an infusion pump. Secondly, the multi-channel signal acquisition module 200 includes a pressure acquisition unit 210 and an electromyography (EMG) acquisition unit 220. The pressure acquisition unit 210 acquires bladder pressure signals through a MEMS pressure sensor built into the pressure measuring chamber of the three-lumen integrated catheter 600, and also acquires the user's abdominal pressure signals through an abdominal pressure sensor 730. Specifically, the pressure acquisition unit 210 in this embodiment can be a pressure sensor assembly. The EMG acquisition unit 220 acquires EMG signals corresponding to the external urethral sphincter through a ring electrode 610 disposed on the distal outer wall of the three-lumen integrated catheter 600. Specifically, the EMG acquisition unit 220 in this embodiment can be an EMG preamplifier. Furthermore, the constant current stimulation output module 300 outputs a charge-balanced bidirectional symmetrical square wave pulse to the external urethral sphincter via the ring electrode 610. The pulse is then conducted through the tissue of the external urethral sphincter to the sacral nerve. It is important to note that the ring electrode 610 is physically located at the external urethral sphincter, and its pressure-sensitive surface is in contact with the electromyographic signals of the external urethral sphincter, allowing for electromyographic acquisition. When switching to stimulation output mode, the output current originates from the ring electrode 610, diffuses through the tissue of the external urethral sphincter, and is conducted to the adjacent sacral nerve branch (S3 nerve root), thereby achieving electrical stimulation of the sacral nerve. In addition, in this embodiment, the synchronization control module 400 hardware-triggers the multi-channel signal acquisition module 200 to synchronously sample at the edge of the output pulse from the constant current stimulation output module 300, and synchronously outputs a hardware timestamp at the moment of stimulation output. Specifically, the synchronization controller 400 in this embodiment can be a synchronization controller employing an FPGA hardware trigger circuit. The result evaluation module 500 performs detrusor-sphincter dyssynergism identification based on the pressure and electromyographic signals obtained through synchronous sampling. Upon identification of detrusor-sphincter dyssynergism, it activates the constant current stimulation output module 300 to perform stepwise stimulation and induce electromyographic threshold recording to obtain a urodynamic assessment report. Furthermore, in this embodiment, the fluid infusion module 100 is connected to the infusion chamber of the three-lumen integrated catheter 600 via a fluid path. The multi-channel signal acquisition module 200 is connected to the MEMS pressure sensor in the pressure measurement chamber and the annular electrode 610 in the lead wire chamber of the three-lumen integrated catheter 600 via signal lines. Additionally, the constant current stimulation output module 300 is also connected to the annular electrode 610 in the lead wire chamber via a stimulation line. The synchronization control module 400 is connected to the constant current stimulation output module 300 and the multi-channel signal acquisition module 200 via control lines. The result evaluation module 500 is connected to the multi-channel signal acquisition module 200 and the synchronization control module 400 via data lines.In this embodiment, the result evaluation module 500 can be a sub-module of the main control module 1001. This will be described in detail below, and will not be repeated here.

[0036] In one embodiment of this application, the three-lumen integrated catheter includes an infusion interface 620, a pressure measuring interface 630, and an electrical interface 640 that are respectively connected to the infusion cavity, the pressure measuring cavity, and the lead wire cavity; wherein, the infusion interface 620 is connected to the liquid infusion module, the pressure measuring interface 630 is connected to the pressure acquisition unit, and the electrical interface 640 is connected to the constant current stimulation output module and the electromyography acquisition unit.

[0037] Specifically, the three-lumen integrated catheter 600 is pre-inserted into the user's bladder through the urethra, and the portion outside the user's body is called the external end of the three-lumen integrated catheter 600. For example... Figure 3As shown, the three-lumen integrated catheter 600 includes an infusion interface 620, a pressure measuring interface 630, and an electrical interface 640, which are respectively connected to the infusion chamber, the pressure measuring chamber, and the lead wire chamber. The infusion interface 620 is located at the external end of the three-lumen integrated catheter 600 and is connected to the infusion chamber. It is used to interface with the liquid infusion module 100 of the multi-channel urodynamic assessment system 1000, allowing infusion fluid to enter the infusion chamber from the liquid infusion module 100 via the infusion interface 620, and then flow into the user's bladder through the infusion port at the distal end of the infusion chamber. The pressure measuring interface 630 is located at the external end of the three-lumen integrated catheter 600 and is connected to the pressure measuring chamber. It is used to interface with the pressure acquisition unit 210, allowing the pressure signal acquired by the MEMS pressure sensor in the pressure measuring chamber to be transmitted to the pressure acquisition unit 210 via the pressure measuring interface 630. An electrical interface 640 is located at the external end of the three-lumen integrated catheter 600 and is electrically connected to the insulated wires inside the catheter cavity. It is used to interface with the constant current stimulation output module 300 and the electromyography (EMG) acquisition unit 220, allowing the electrical stimulation pulses output by the constant current stimulation output module 300 to be transmitted to the ring electrode 610 via the electrical interface 640 and the insulated wires inside the catheter cavity. Simultaneously, it allows the EMG signals acquired by the ring electrode 610 to be transmitted to the EMG acquisition unit 220 via the insulated wires inside the catheter cavity and the electrical interface 640. The infusion interface 620 can be a Luer connector for a detachable, sealed connection to the infusion tubing of the liquid infusion module 100. The pressure measurement interface 630 is an electrical connector for electrical connection to the signal line of the pressure acquisition unit 210. The electrical interface 640 can be a multi-core electrical connector for simultaneously connecting the stimulation output line of the constant current stimulation output module 300 and the signal input line of the EMG acquisition unit 220. Furthermore, it is important to note the power supply method for the catheter and electrodes. The pressure measurement interface 630 of the three-lumen integrated catheter 600 is an active electrical interface, which internally houses power supply and signal lines. The pressure acquisition unit 210 provides DC operating voltage to the MEMS pressure sensor 621 within the pressure measurement chamber through the power supply lines within the pressure measurement interface 630. The pressure signal detected by the MEMS pressure sensor 621 is transmitted back to the pressure acquisition unit 210 via the signal lines within the pressure measurement interface 630. The electrical interface 640 is a multi-core active electrical interface, simultaneously connecting the electromyography acquisition unit 220 and the constant current stimulation output module 300. The power supply for the ring electrode 610 is provided by the electromyography (EMG) acquisition unit 220 and the constant current stimulation output module 300 in a time-sharing manner: In EMG acquisition mode, the EMG acquisition unit 220 provides working power to the ring electrode 610 through the power supply line in the electrical interface 640, and the EMG signal acquired by the ring electrode 610 is transmitted back to the EMG acquisition unit 220 through the signal line in the electrical interface 640; In electrical stimulation mode, the electrical stimulation pulse output by the constant current stimulation output module 300 is transmitted to the ring electrode 610 through the stimulation line in the electrical interface 640.The acquisition mode and stimulation mode are switched in a time-sharing manner by the synchronization control module 400, with only one module driving the ring electrode 610 through the electrical interface 640 at any given time. The power supply line, signal line, and stimulation line are all isolated from each other within the electrical interface 640 and the lead wire cavity to avoid signal crosstalk. The infusion interface 620 of the three-lumen integrated catheter 600 is a passive fluid path interface, used only for fluid flow and requiring no power supply. The abdominal pressure sensor 730, the surface-mount electrode 710, and the anal electrode 720 are all external sensors, directly powered by the pressure acquisition unit 210 and the electromyography acquisition unit 220 respectively through their respective connecting cables.

[0038] In some other embodiments of this application, the pressure acquisition unit is also used to calculate the detrusor pressure signal based on the bladder pressure signal and the abdominal pressure signal.

[0039] Specifically, such as Figure 3 As shown, the pressure acquisition unit 210 acquires bladder pressure signals through a MEMS pressure sensor within the pressure measurement chamber of the three-lumen integrated catheter 600, and also acquires user abdominal pressure signals through an abdominal pressure sensor 730. Based on this, the pressure acquisition unit 210 is also used to calculate the detrusor pressure signal based on the bladder pressure signal and the abdominal pressure signal. Simply put, detrusor pressure equals bladder pressure minus abdominal pressure. During bladder filling and urination, pressure changes in the abdominal cavity, such as coughing, changes in body position, and active exertion by the user, are synchronously transmitted to the bladder, causing corresponding changes in the bladder pressure reading. To obtain the true pressure generated by the active contraction of the detrusor muscle itself, the abdominal pressure component needs to be subtracted from the bladder pressure. The pressure acquisition unit 210 acquires bladder pressure signals and abdominal pressure signals in a synchronous sampling manner, ensuring that the two signals are precisely aligned in time, and then calculates the detrusor pressure signal point by point through the built-in subtraction unit. In this embodiment, the sampling rate of both bladder pressure signals and abdominal pressure signals is not less than 200 times per second, ensuring that the complete dynamic process of detrusor muscle contraction and abdominal pressure changes can be captured.

[0040] In some embodiments of this application, the electromyography (EMG) acquisition unit further includes a first channel for acquiring abdominal muscle EMG signals via surface-mount electrodes, a second channel for acquiring anal sphincter EMG signals via electrodes, and a third channel for acquiring external urethral sphincter EMG signals via a ring electrode 610.

[0041] Specifically, the electromyography (EMG) acquisition unit 220 also includes a first channel for acquiring abdominal muscle EMG signals via a surface-mounted electrode 710, a second channel for acquiring anal sphincter EMG signals via an electrode, and a third channel for acquiring external urethral sphincter EMG signals via a ring electrode 610. The surface-mounted electrode 710 of the first channel is a skin electrode attached to the user's abdominal skin surface to acquire EMG signals generated during abdominal muscle contraction. The abdominal muscle EMG signals are used to monitor whether the user actively contracts their abdominal muscles due to tension, breath-holding, or changes in body position, thereby determining whether the pressure increase in the bladder pressure signal is caused by active abdominal muscle exertion. Based on this, when the amplitude of the abdominal muscle EMG signal exceeds a preset threshold, the system can mark the bladder pressure signal and detrusor muscle pressure signal acquired synchronously within that time period as data segments interfered with by the user's active exertion. These data segments are not included in the auxiliary identification and subsequent evaluation process for detrusor-sphincter muscle dysco-coordination. The advantage of this is that by removing interfering data segments before analysis, erroneous judgments due to poor user cooperation can be avoided. The second channel's anal electrode 720 is either a surface electrode or an internal electrode for collecting electromyographic (EMG) signals from the anal sphincter. Since the anal sphincter and the external urethral sphincter are innervated by the same nerve, the pudendal nerve, the anal sphincter's EMG signal can serve as a reference signal for the external urethral sphincter's EMG signal, used to subsequently determine whether abnormal contraction of the external urethral sphincter originates from neurogenic lesions or local muscle lesions. Furthermore, the third channel, through a ring electrode 610, collects EMG signals from the external urethral sphincter, serving as a core signal channel for assessing detrusor-sphincter dyssynergism.

[0042] In one embodiment of this application, the electromyography acquisition unit adopts a differential bipolar input method and has an electrode impedance detection function.

[0043] Specifically, the electromyography (EMG) acquisition unit 220 employs a differential bipolar input method and features electrode impedance detection. The differential bipolar input method means that each acquisition channel of the EMG acquisition unit 220 has two input terminals, each connected to one of the two electrode contacts of the same electrode pair. Both input terminals simultaneously measure the potential difference between the electrode pairs. The differential input method effectively suppresses common-mode interference signals. Identical interference signals present simultaneously on both input terminals, such as power frequency interference and electromagnetic radiation interference, are canceled out during differential amplification. The potential difference signal between the two terminals, i.e., the EMG signal from the target muscle, is effectively amplified, thereby significantly improving the signal-to-noise ratio of the EMG signal. The electrode impedance detection function means that the EMG acquisition unit 220 can measure the contact impedance between each electrode contact and the skin or tissue before and during acquisition. The normal range of electrode impedance is 500 ohms to 5000 ohms. When the impedance of any electrode exceeds this preset range, the EMG acquisition unit 220 issues an alarm signal, prompting a person skilled in the art or an operator to check the electrode contact status.

[0044] In some other embodiments of this application, the constant current stimulation output module includes at least one channel for isolating constant current output and has short-circuit protection, overcurrent protection, charge imbalance detection and output abnormality alarm functions.

[0045] Specifically, the constant current stimulation output module 300 includes at least one channel of isolated constant current output and features short-circuit protection, overcurrent protection, charge imbalance detection, and output abnormality alarm functions. It is important to note that "constant current output" here means that the current intensity output by the constant current stimulation output module 300 does not change with variations in load impedance. During electrical stimulation, the contact impedance between the electrode and tissue may change due to factors such as changes in user position and tissue fluid distribution. The constant current output ensures that the actual current intensity flowing through the tissue remains consistent with the set value even under these impedance changes. "Isolated output" means that the stimulation output circuit of the constant current stimulation output module 300 is electrically isolated from the system's main circuit using electrical isolation devices such as optocouplers or isolation transformers, preventing abnormal current from flowing to the user through the stimulation electrodes. The short-circuit protection function means that when a short circuit occurs in the stimulation output circuit, the constant current stimulation output module 300 can immediately detect the short circuit and cut off the output. The overcurrent protection function means that when the output current exceeds a preset safety threshold, the constant current stimulation output module 300 can automatically limit the output current and issue an alarm. The charge imbalance detection function refers to the constant current stimulation output module 300 continuously monitoring the charge quantity of the positive and negative phase pulses. When the difference between the positive and negative charge quantities exceeds the preset allowable deviation, it is determined to be a charge imbalance and an alarm is issued. The output abnormality alarm function refers to the constant current stimulation output module 300 issuing an alarm signal to the system operator through sound, light, or screen prompts when any of the above abnormalities occur.

[0046] In some other embodiments of this application, the synchronization control module includes a hardware trigger synchronization unit and a hardware timestamp marking unit. The hardware trigger synchronization unit triggers the multi-channel signal acquisition module to synchronously sample at the edge of the pulse, and the hardware timestamp marking unit outputs a mark bit and writes it into the data stream at the moment of stimulus output.

[0047] Specifically, the synchronization control module 400 includes a hardware trigger synchronization unit and a hardware timestamp marker unit. The hardware trigger synchronization unit triggers the multi-channel signal acquisition module 200 to synchronously sample at the edge of the pulse output by the constant current stimulation output module 300. The hardware timestamp marker unit outputs a marker bit and writes it into the data stream at the moment of stimulation output. The working principle of the hardware trigger synchronization unit is as follows: When the constant current stimulation output module 300 outputs a stimulation pulse, its pulse waveform has a rising edge (the instant from zero potential to the preset stimulation amplitude) and a falling edge (the instant from the preset stimulation amplitude back to zero potential). The hardware trigger synchronization unit directly detects this rising or falling edge and sends a trigger signal to the multi-channel signal acquisition module 200 through hardware circuitry at the instant the edge is detected. After receiving the trigger signal, the multi-channel signal acquisition module 200 immediately initiates a sampling operation, synchronously acquiring pressure signals and electromyographic signals from all channels. The entire triggering process is directly completed by the hardware circuitry without any software processing or interrupt response. The hardware timestamp unit generates a timestamp containing the current moment information simultaneously with the hardware-triggered synchronization unit's sampling. This timestamp is then written into the data stream and stored in association with the synchronously sampled data. In other words, the hardware timestamp unit in this embodiment marks a precise moment at the moment the stimulus is emitted. Even if the stimulus causes amplifier saturation and prevents the acquisition of effective data, this timestamp remains intact and is not destroyed by stimulus artifacts. Based on this, subsequent algorithms can use this timestamp to accurately pinpoint the moment the stimulus occurred, thereby finding the correct time period for analyzing the induced electromyographic response within the signal after saturation recovery.

[0048] In some other embodiments, when the result evaluation module performs auxiliary identification of detrusor and sphincter dyssynergism, it simultaneously analyzes the temporal relationship between detrusor pressure and external urethral sphincter electromyography (EMG) signals to determine whether there is abnormal contraction of the external urethral sphincter during detrusor contraction. If there is paradoxical contraction of the external urethral sphincter during detrusor contraction, the result evaluation module is also used to determine the type of abnormal contraction of the external urethral sphincter based on the synchronicity of the external urethral sphincter EMG signals and the anal sphincter EMG signals. If the type of abnormal contraction of the external urethral sphincter is neurogenic, the constant current stimulation output module is activated to perform stepwise stimulation and induce EMG threshold recording; or, if the type of abnormal contraction of the external urethral sphincter is localized muscular, a corresponding urodynamic assessment report for the user is directly generated.

[0049] Specifically, the result evaluation module 500 acquires the detrusor muscle pressure signal output by the pressure acquisition unit 210 and the external urethral sphincter electromyography (EMG) signal output by the EMG acquisition unit 220, aligns them on the time axis, and analyzes their temporal relationship point by point. In a normal urination reflex, when the detrusor muscle begins to contract (i.e., the detrusor muscle pressure increases), the external urethral sphincter should relax synchronously (i.e., the EMG signal amplitude decreases) to allow urine to be expelled smoothly. Based on this, during fluid perfusion, if the external urethral sphincter EMG signal amplitude increases or remains unchanged when the detrusor muscle contracts, it is determined that there is abnormal contraction of the external urethral sphincter during detrusor muscle contraction, i.e., there is detrusor-spontine dyssynergy. In the case of abnormal contraction of the external urethral sphincter during detrusor muscle contraction, the result evaluation module 500 is also used to determine the type of abnormal contraction of the external urethral sphincter based on the synchronicity of the external urethral sphincter EMG signal and the anal sphincter EMG signal. When both electromyographic (EMG) signals are synchronously abnormal, it indicates that the lesion is located at the neural level and belongs to the neurogenic type. When the EMG signal of the external urethral sphincter is abnormal while the EMG signal of the anal sphincter is normal, it indicates that the lesion is located in the external urethral sphincter itself and belongs to the local muscular type. Based on this, when the abnormal contraction type of the external urethral sphincter is determined to be of the local muscular type, this system directly generates the corresponding urodynamic assessment report for the user. It should be noted that when the abnormal contraction type of the external urethral sphincter is determined to be of the local muscular type, the urodynamic assessment report finally generated in this embodiment will include at least the following: the identification result of detrusor-sphincter dyssynergism, the abnormal contraction type of the external urethral sphincter being of the local muscular type, the determination criteria including abnormal EMG signal of the external urethral sphincter and normal EMG signal of the anal sphincter, and the conclusion that electrical stimulation therapy may be ineffective and implantation of a permanent sacral nerve stimulator is not recommended, among other things. Furthermore, during fluid infusion, if the amplitude of the electromyographic signal of the external urethral sphincter decreases when the detrusor muscle contracts, it is determined that the sphincter relaxes in synergy with the detrusor muscle during contraction, i.e. there is no detrusor-spontine dyssynergy. In this case, the system will directly generate a corresponding urodynamic assessment report for the user, which will include at least the recognition result that the detrusor-spontine synergy is normal.

[0050] Conversely, in another case, if the abnormal contraction type of the external urethral sphincter is determined to be neurogenic, the constant current stimulation output module 300 is activated to perform subsequent stepwise stimulation and induce electromyographic threshold recording.

[0051] In one embodiment of this application, when performing stepwise stimulation and induced electromyography threshold recording, the result evaluation module increases the intensity of the stimulation current in a stepwise manner, simultaneously records the amplitude of the induced electromyographic response at each intensity, and automatically identifies the induced response threshold.

[0052] Specifically, the stepwise stimulation in this embodiment is implemented as follows: the result evaluation module 500 controls the constant current stimulation output module 300 to output electrical stimulation pulses through the ring electrode 610, starting from an initial current value (e.g., 0.1 mA). Furthermore, the pulse width and stimulation frequency parameters used in this pulsed electrical stimulation can be conventional stimulation parameters set by those skilled in the art based on experience. After catheter insertion, the ring electrode 610 directly contacts the external urethral sphincter, and the output electrical stimulation current is conducted through the tissue at the external urethral sphincter to the adjacent sacral nerve branches (mainly the S3 nerve root), thereby producing an electrical stimulation effect on the sacral nerve. A preset number (e.g., 10) of stimulation pulses are continuously output at each current intensity, and then the current intensity is increased in fixed steps, such as 0.1 mA, until a preset maximum current value, such as 25.5 mA, is reached or a clear induced electromyographic response is observed. At each current intensity, the synchronization control module 400 ensures precise synchronization between the stimulation output and signal acquisition. The electromyography (EMG) acquisition unit 220 acquires evoked EMG signals from the user's external urethral sphincter via the ring electrode 610. This signal reflects the change in the efferent command of the sacral nerve to the external urethral sphincter after electrical stimulation. Based on this, the automatic identification method for the evoked response threshold in this embodiment is as follows: the result evaluation module 500 processes the EMG signals acquired at each current intensity and extracts the EMG response amplitude within a preset time window after stimulation. The evoked response amplitude gradually increases with the increase of the stimulation current intensity. Based on the above, the result evaluation module 500 in this embodiment automatically identifies the stimulation current intensity corresponding to when the evoked response amplitude first reaches the preset target EMG threshold (e.g., 50 microvolts) as the user's evoked response threshold. In other words, the evoked response threshold in this embodiment is the stimulation current intensity corresponding to when the evoked response amplitude first reaches the preset target EMG threshold. It should be noted that the target EMG threshold of 50 microvolts in this application is an exemplary value, and those skilled in the art can set it manually according to clinical practice.

[0053] In some other embodiments of this application, the result evaluation module is also used to obtain the user's target electrical stimulation parameters based on the amplitude of the evoked electromyographic response corresponding to each step stimulation intensity in the test results recorded by the step stimulation and evoked electromyographic threshold; the result evaluation module is also used to generate a urodynamic evaluation report corresponding to the user based on the abnormal contraction type of the external urethral sphincter and the user's target electrical stimulation parameters.

[0054] Specifically, the result evaluation module 500 is also used to obtain the user's target electrical stimulation parameters based on the amplitude of the evoked electromyographic response corresponding to each step of stimulation intensity in the test results recorded by the step stimulation and evoked electromyographic threshold. Further, the test results recorded by the step stimulation and evoked electromyographic threshold include the current value corresponding to each step of stimulation intensity, the amplitude of the electromyographic response evoked at that intensity, and the evoked response threshold automatically identified by the system. Based on this, the result evaluation module 500 organizes and analyzes this data to finally obtain the target electrical stimulation parameters corresponding to the user. It should be noted that the user's target electrical stimulation parameters here refer to the combination of electrical stimulation parameters that can effectively induce an electromyographic response with the lowest stimulation intensity, specifically including the stimulation current intensity (i.e., the evoked response threshold automatically identified by the system above), pulse width, and stimulation frequency. It should be noted that the pulse width and stimulation frequency in the target electrical stimulation parameters here can be conventional stimulation parameters set manually by those skilled in the art based on experience. Then, the result evaluation module 500 is also used to generate a urodynamic assessment report corresponding to the user based on the type of abnormal contraction of the external urethral sphincter and the user's target electrical stimulation parameters. Based on this, the urodynamic assessment report finally generated in this embodiment includes at least the following: the identification result of detrusor and sphincter dyssynergism, the type of abnormal contraction of the external urethral sphincter as neurogenic or local muscular, the complete data of stepwise stimulation and evoked electromyographic threshold recording, including the intensity of each stepwise stimulation and its corresponding evoked electromyographic response amplitude, the automatically identified evoked response threshold, and the user's target electrical stimulation parameters, etc.

[0055] In summary, the multi-channel urodynamic assessment system provided in this application has the following beneficial effects: First, it integrates fluid perfusion, multi-channel signal acquisition, constant current stimulation output, synchronous control, and result evaluation functions into one system, allowing verification of the user's responsiveness to sacral nerve electrical stimulation via an external catheter electrode. Second, through a hardware-triggered synchronization mechanism, it ensures precise alignment between the stimulation output time and the sampling time of all acquisition channels, providing a reliable data foundation for stimulation and response timing analysis. Third, by marking stimulation events with hardware timestamps, the timestamps are still fully preserved even in the case of short-term amplifier saturation, allowing the back-end algorithm to accurately locate the evoked window after stimulation. Fourth, by simultaneously monitoring abdominal muscle electromyography (EMG), anal sphincter EMG, and external urethral sphincter EMG, multi-channel cross-validation is achieved, eliminating EMG artifacts introduced by the activation of non-target muscle groups. Fifth, through a step-by-step evaluation process involving detrusor and sphincter dyssynergy-assisted identification and stepwise stimulation and evoked EMG threshold recording, a complete evaluation chain from functional assessment to stimulation effect verification is realized.

[0056] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A multi-channel urodynamic assessment system based on sacral nerve stimulation, implemented using a pre-inserted three-lumen integrated catheter in the user's bladder, the three-lumen integrated catheter comprising an infusion lumen, a pressure measurement lumen, and a lead guide lumen, characterized in that, include: The liquid infusion module is used to infuse liquid into the bladder through the infusion chamber of the three-lumen integrated catheter and to count the liquid infusion volume in real time. The multi-channel signal acquisition module includes a pressure acquisition unit and an electromyography (EMG) acquisition unit. The pressure acquisition unit acquires bladder pressure signals through a MEMS pressure sensor in the pressure measuring chamber of the three-lumen integrated catheter and also acquires user abdominal pressure signals through an abdominal pressure sensor. The EMG acquisition unit acquires EMG signals corresponding to the external urethral sphincter through a ring electrode located on the outer wall of the distal end of the three-lumen integrated catheter. A constant current stimulation output module is used to output a charge-balanced bidirectional symmetrical square wave pulse to the sacral nerve through the ring electrode; and a synchronization control module is used to hardware trigger the multi-channel signal acquisition module to synchronously sample at the edge of the pulse output by the constant current stimulation output module, and to synchronously output a hardware timestamp at the moment of stimulation output. The result evaluation module is used to perform auxiliary identification of detrusor and sphincter dyssynergy based on the pressure signal and electromyographic signal obtained by the synchronous sampling. When detrusor and sphincter dyssynergy is identified, the constant current stimulation output module is activated to perform stepwise stimulation and induce electromyographic threshold recording to obtain a urodynamic evaluation report.

2. The system according to claim 1, characterized in that, The three-lumen integrated catheter includes an infusion interface, a pressure measurement interface, and an electrical interface that are respectively connected to the infusion cavity, the pressure measurement cavity, and the lead wire cavity; wherein, the infusion interface is connected to the liquid infusion module, the pressure measurement interface is connected to the pressure acquisition unit, and the electrical interface is connected to the constant current stimulation output module and the electromyography acquisition unit.

3. The system according to claim 2, characterized in that, The pressure acquisition unit is also used to calculate the detrusor pressure signal based on the bladder pressure signal and the abdominal pressure signal.

4. The system according to claim 3, characterized in that, The electromyography (EMG) acquisition unit also includes a first channel for acquiring abdominal muscle EMG signals via surface-mounted electrodes, a second channel for acquiring anal sphincter EMG signals via electrodes, and a third channel for acquiring external urethral sphincter EMG signals via the ring electrode.

5. The system according to claim 4, characterized in that, The electromyography (EMG) acquisition unit adopts a differential bipolar input method and has an electrode impedance detection function.

6. The system according to claim 5, characterized in that, The constant current stimulation output module includes at least one channel for isolated constant current output and has short-circuit protection, overcurrent protection, charge imbalance detection, and output abnormality alarm functions.

7. The system according to claim 6, characterized in that, The synchronization control module includes a hardware trigger synchronization unit and a hardware timestamp marking unit. The hardware trigger synchronization unit triggers the multi-channel signal acquisition module to synchronously sample at the edge of the pulse. The hardware timestamp marking unit outputs a mark bit and writes it into the data stream at the moment of stimulus output.

8. The system according to claim 7, characterized in that, When the result evaluation module performs the auxiliary identification of detrusor and sphincter dyssynergy, it simultaneously analyzes the temporal relationship between detrusor pressure and external urethral sphincter electromyography signal to determine whether there is abnormal contraction of the external urethral sphincter when the detrusor contracts. In cases where the external urethral sphincter exhibits paradoxical contraction during detrusor muscle contraction, the result evaluation module is further used to determine the type of abnormal contraction of the external urethral sphincter based on the synchronicity between the electromyographic signals of the external urethral sphincter and the electromyographic signals of the anal sphincter. If the abnormal contraction type of the external urethral sphincter is neurogenic, the constant current stimulation output module is activated to perform stepwise stimulation and induce electromyographic threshold recording; or, if the abnormal contraction type of the external urethral sphincter is local muscular, a urodynamic assessment report corresponding to the user is directly generated.

9. The system according to claim 8, characterized in that, When performing the stepwise stimulation and induced electromyographic threshold recording, the result evaluation module increases the intensity of the stimulation current in a stepwise manner, simultaneously records the amplitude of the induced electromyographic response at each intensity, and automatically identifies the induced response threshold.

10. The system according to claim 9, characterized in that, The result evaluation module is also used to obtain the user's target electrical stimulation parameters based on the amplitude of the evoked electromyographic response corresponding to each step stimulation intensity in the test results recorded by the step stimulation and evoked electromyographic threshold. The result evaluation module is also used to generate a urodynamic evaluation report for the user based on the type of abnormal contraction of the external urethral sphincter and the user's target electrical stimulation parameters.

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