Intelligent distraction drainage device for neurosurgical posterior cranial surgery and control method thereof

Abstract

The application discloses an intelligent distraction drainage device for neurosurgery posterior cranium operation and a control method thereof, and belongs to the technical field of medical instruments. The device comprises a distraction module, a drainage tube, a lumbar vertebra reference pressure sensor and an intelligent pump control module. The front end of a distraction blade of the distraction module is embedded with a micro Doppler probe for blood vessel identification. The drainage tube is integrated with a micro intracranial pressure sensor, a flow sensor and an optical viscosity detection unit. The lumbar vertebra reference pressure sensor is used for acquiring the pressure of a spinal cord cavity. The intelligent pump control module comprises a peristaltic pump and a precision proportional valve with forward and reverse rotation functions. A main controller executes control logic such as pressure balance initialization, stepwise release, forward and reverse pulse perfusion and gradient closing. Through multi-sensor fusion and automatic control, the application realizes blood vessel avoidance, cross-region pressure balance and accurate drainage regulation and control, and solves the problems of difficult tissue identification and insufficient pressure control in the prior art. The application can reduce the blood vessel injury rate and the flow tube blockage rate, and significantly improves the safety of posterior cranium operation.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to an intelligent dilation and drainage device and its control method for posterior cranial surgery in neurosurgery. Background Technology

[0002] In posterior cranial surgery, good surgical field exposure and effective drainage of effusion are crucial for surgical success. Current techniques typically integrate posterior cranial dilation and drainage devices, using mechanical structures to achieve dilation and prevent clogging. Most employ a mechanical linkage between a movable cone and a retaining ring mechanism, using physical sliding to push the outer ring tube to prevent blockage. However, this type of purely mechanical structure has the following technical drawbacks in practical applications: First, the lack of tissue identification ability leads to a high risk of vascular injury. In secondary surgeries or complex cases, due to scar tissue adhesions and the disappearance of normal anatomical structures, critical vessels such as the posterior inferior cerebellar artery (PICA) may be pulled and displaced. Simply relying on mechanical dilation can easily injure these vessels. Statistics show that the incidence of vascular injury in secondary surgeries of the posterior fossa can reach 8%–15%, and in severe cases, it can lead to intraoperative death or permanent neurological deficits.

[0003] Second, the drainage control methods are outdated and unable to cope with sudden pressure changes. Existing mechanical anti-blocking structures can only achieve binary control of "movement" and "immobility," failing to precisely quantify flow rate or dynamically adjust according to real-time changes in intracranial pressure. Clinical data shows that the sudden outflow of cerebrospinal fluid upon opening the dura mater can cause a precipitous drop in intracranial pressure (often exceeding 10 mmHg / s). This pressure fluctuation can easily trigger fatal complications such as brainstem displacement and cerebellar herniation, which conventional devices cannot respond to in a timely manner.

[0004] Third, the issue of cross-regional pressure balance has been overlooked. Posterior cranial surgery often involves pressure coordination between the cranial cavity and the spinal canal, especially in patients with cerebellar tonsillar herniation and syringomyelia, where a significant pressure gradient exists between the cranial cavity and the spinal canal. Existing devices only focus on a single drainage channel and do not consider the regulation of cross-regional pressure gradients, resulting in a postoperative cerebrospinal fluid circulation disorder rate as high as 20%–30%.

[0005] Fourth, the problem of drainage tube blockage has not been effectively resolved. Thick fluid or blood clots easily block the side holes of the drainage tube. Traditional mechanical scraping anti-blockage structures have limited effectiveness and may damage tissue. Clinical statistics show that the blockage rate of posterior cranial drainage tubes is approximately 12%–18%, requiring repeated flushing or even tube replacement, increasing the risk of infection.

[0006] Therefore, developing an intelligent drainage device with tissue identification capabilities, precise closed-loop control, ability to balance cross-regional pressure, and effective anti-blockage is of significant clinical importance. Summary of the Invention

[0007] In view of this, the purpose of the present invention is to provide an intelligent dilation and drainage device and its control method for posterior cranial surgery in neurosurgery. The intelligent dilation and drainage device has tissue recognition capabilities, can achieve precise closed-loop control, can balance cross-regional pressure, and effectively prevents blockage, and has important clinical significance.

[0008] This invention is achieved through the following technical solution: A smart dilation and drainage device for posterior cranial surgery in neurosurgery, comprising: The expansion module includes a pair of expansion blades, the front end of which is embedded with a miniature Doppler probe for identifying the location of blood vessels during surgery; The drainage tube has its front end located between the openings, and its body integrates a miniature intracranial pressure sensor, a miniature flow sensor, and an optical viscosity detection unit. The lumbar reference pressure sensor is independently installed in the subarachnoid space of the lumbar spine to obtain reference values ​​of spinal canal pressure. The intelligent pump control module includes a peristaltic pump and a precision proportional valve. The peristaltic pump has forward and reverse rotation functions to realize the suction and injection of liquid. The main controller is electrically connected to the miniature Doppler probe, the miniature intracranial pressure sensor, the miniature flow sensor, the optical viscosity detection unit, the lumbar spine reference pressure sensor, and the intelligent pump control module, respectively. The main controller is configured to execute the following control logic: Before cutting the dura mater, the intelligent pump control module is controlled to perform pre-inflation or pre-drainage based on the difference between the miniature intracranial pressure sensor and the lumbar spine reference pressure sensor, so that the pressure in the cranial cavity and the spinal canal reaches a balanced state. At the moment the dura mater is cut, the rate of intracranial pressure decrease is monitored in real time. When the rate of decrease exceeds the preset safety threshold, the drainage tube is automatically clamped. During the drainage process, the peristaltic pump is controlled to execute a forward and reverse pulse perfusion mode. Through alternating forward suction and reverse push, liquid pulse waves are generated to flush the side holes and cavity walls of the drainage tube.

[0009] Furthermore, the main controller is also configured as follows: During the expansion process, an augmented reality overlay image of the blood vessel avoidance zone is generated on the display screen based on the blood flow signal acquired by the micro Doppler probe. When the impedance sensor of the expanding blade detects a sudden increase in expanding resistance and a change in Doppler signal characteristics, it determines that the blade has contacted a blood vessel and automatically stops expanding and issues an alarm.

[0010] Further specifying, the specific parameters of the forward and reverse pulse perfusion mode are: forward pulse speed 30-50 rpm, duration 0.3-0.8 seconds; reverse pulse speed 15-25 rpm, duration 0.1-0.3 seconds; pulse interval 0.5-2 seconds; number of cycles 5-15.

[0011] Furthermore, the main controller is also equipped with a gradient shut-off mode: before closing the drainage at the end of the surgery, the drainage resistance is gradually increased to linearly reduce the drainage rate to zero within 5-15 minutes, while monitoring intracranial pressure fluctuations.

[0012] Further, it also includes external support equipment, which is a multi-degree-of-freedom robotic arm.

[0013] Further specifying, the optical viscosity detection unit includes an LED light source and a photoelectric receiver, which are installed on opposite sides of the drainage tube to monitor the viscosity of the drainage fluid in real time. The main controller compensates and corrects the pulse perfusion parameters based on the viscosity data.

[0014] Further specified, the safety threshold is set to an intracranial pressure drop rate > 5 mmHg / s. When this threshold is exceeded, the main controller drives the precision proportional valve to completely clamp the pipeline within 50 ms and triggers an audible and visual alarm.

[0015] A control method for an intelligent dilation and drainage device for neurosurgical posterior cranial surgery includes the following steps performed by the main controller (5): Step S1: Pressure equalization initialization The main controller reads the intracranial pressure value P1 from the miniature intracranial pressure sensor and the spinal canal pressure value P2 from the lumbar reference pressure sensor, and calculates the pressure difference ΔP = P1 - P2. If |ΔP|> the preset threshold, then: When ΔP>0, a control signal is sent to the intelligent pump control module to start the peristaltic pump to draw water in the forward low speed until |ΔP|≤ the preset threshold. When ΔP<0, a control signal is sent to the intelligent pump control module to start the peristaltic pump to inject artificial cerebrospinal fluid into the cavity at a low speed in reverse until |ΔP|≤ the preset threshold. Step S2: Stepped release control Upon receiving a trigger signal indicating dural incision, the main controller enters a high-speed sampling mode with a sampling rate ≥100Hz to monitor the rate of intracranial pressure decrease in real time. If s > preset safety threshold, a control signal is sent to the precision proportional valve to drive it to clamp the drainage tube and trigger an alarm. After the pressure stabilizes, a control signal is sent to the peristaltic pump to start the forward and reverse pulse perfusion mode: the peristaltic pump is controlled to rotate forward and reverse alternately to generate liquid pulse waves to flush the side holes and cavity walls of the drainage tube; Step S3: Gradient Closure Control Upon receiving a trigger signal indicating the end of the surgery, the main controller initiates a gradient shutdown mode, gradually increasing the drainage resistance to linearly reduce the drainage rate to zero within a preset time while monitoring intracranial pressure fluctuations.

[0016] Further, in step S2, the specific execution parameters of the positive and negative pulse infusion mode are dynamically adjusted according to the viscosity data fed back by the optical viscosity detection unit (23): when the liquid viscosity is detected to be higher than the preset threshold, the positive pulse speed is increased to 40-50 rpm and the pulse duration is extended to 0.6-0.8 seconds.

[0017] Furthermore, the step S2 is preceded by a blood vessel avoidance control step: The main controller receives blood flow signals acquired by the miniature Doppler probe and generates an augmented reality overlay image of the blood vessel avoidance zone on the display screen; When the impedance sensor that opens the blade detects a sudden increase in opening resistance and a change in Doppler signal characteristics, it is determined that the blade has contacted a blood vessel, automatically stops opening, and issues an audible and visual alarm.

[0018] The beneficial effects of this invention are as follows: Compared with the prior art, the present invention has the following beneficial effects: Significantly reduces the risk of vascular injury: By integrating a miniature Doppler probe and augmented reality image guidance, real-time identification and avoidance of vascular locations are achieved. Clinically validated, in 20 secondary posterior cranial surgeries using this invention, the incidence of vascular injury was 0%, while in the control group (20 cases) using traditional instruments, the incidence of vascular injury was 15% (3 cases). The accuracy of vascular identification was improved from 65% relying on experience in the traditional method to 98%.

[0019] Effectively suppressing pressure oscillations and preventing brainstem displacement: Pressure equalization initialization can control the pressure difference between the intracranial cavity and the spinal canal within 2 mmHg; stepwise release control reduces the rate of intracranial pressure decrease at the moment of dural incision from an average of 12.5 mmHg / s in traditional surgery to 3.2 mmHg / s, a reduction of 74.4%. No brainstem displacement or cerebellar herniation occurred in this group of cases, while the incidence rate in the control group was 10% (2 cases).

[0020] Achieve precise flow control: Closed-loop control ensures that the deviation between the actual flow rate and the set value is less than ±0.5 mL / h, with a control accuracy at the milliliter / hour level, which is far superior to manual adjustment or mechanical control (the deviation is often greater than ±5 mL / h).

[0021] Significantly reduced drainage tube blockage rate: In the positive and negative pulse irrigation mode, the drainage tube blockage rate was 0% in 20 surgeries, while the blockage rate in the traditional negative pressure drainage control group was 15% (3 cases), and no intraoperative irrigation or drainage tube replacement was required.

[0022] Improved postoperative recovery indicators: The average postoperative hospital stay of patients using this invention was shortened to 7.2±1.5 days, which was 37.4% less than that of the control group (11.5±2.3 days); the incidence of postoperative cerebrospinal fluid leakage was reduced to 0%, compared to 10% (2 cases) in the control group.

[0023] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0024] Figure 1 This invention provides a three-dimensional view of the intelligent dilation and drainage device for posterior cranial surgery in neurosurgery. Figure 1 ; Figure 2 This invention provides a three-dimensional view of the intelligent dilation and drainage device for posterior cranial surgery in neurosurgery. Figure 2 ; Figure 3 This is a schematic cross-sectional view of the intelligent dilation and drainage device for neurosurgical posterior cranial surgery of the present invention. Figure 4 For this Figure 2 Enlarged view of A in the middle; Figure 5 This is a schematic diagram of the cross-sectional structure of the front end of the drainage tube; In the diagram: 1. Spread blade; 2. Miniature Doppler probe; 3. First ring body; 4. Second ring body; 5. Connecting seat; 6. Annular recessed platform; 7. Annular cover plate; 8. Support rod; 9. Screw sleeve; 10. Slot; 11. Limiting groove; 12. Limiting protrusion; 13. Drainage tube; 14. Miniature intracranial pressure sensor; 15. Miniature flow sensor; 16. LED light source; 17. Photodetector. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] 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 further defined and explained in subsequent figures.

[0028] In the above description of the present invention, it should be noted that the terms "one side," "the other side," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is conventionally placed during use. These terms are used only for the convenience of describing the present invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Furthermore, terms such as "identical" do not imply that components must be absolutely identical; minor differences are permissible. The term "perpendicular" simply means that the positional relationship between components is more perpendicular than "parallel," not that the structure must be perfectly perpendicular; a slight tilt is acceptable.

[0030] Please see Figure 1-5 The present invention provides a technical solution: an intelligent dilation and drainage device and its control method for posterior cranial surgery in neurosurgery.

[0031] Example 1 This embodiment provides an intelligent dilation and drainage device for posterior cranial surgery in neurosurgery, including a dilation module, a drainage tube 13, a lumbar spine reference pressure sensor, an intelligent pump control module, and a main controller.

[0032] The dilation module includes a pair of dilation blades 1 and a mounting bracket for mounting the dilation blades 1. A drive mechanism is mounted on the mounting bracket to drive the opening and closing of the dilation blades 1. A miniature Doppler probe 2 (model: MD-10, operating frequency 8MHz) is embedded at the front end of the dilation blade 1 for identifying the vessel location during surgery. An impedance sensor (model: FSR402) is integrated at the dilation joint to monitor the dilation resistance in real time. The mounting bracket is a ring structure, and the expanding blade 1 is located inside the ring structure; The mounting bracket includes a first ring body 3 and a second ring body 4. A limiting structure is provided between the first ring body 3 and the second ring body 4, and the first ring body 3 and the second ring body 4 are interlocked by the limiting structure and can rotate freely relative to each other. The outer wall of the first ring body 3 is provided with a connecting seat 5, which can be used to connect with a multi-degree-of-freedom operating arm. An annular recess 6 is provided along the top surface of the inner side of the first ring body 3. The second ring body 4 is engaged in the annular recess 6 and can rotate freely. The top surface of the first ring body 3 is covered with an annular cover plate 7, which is connected to the first ring body 3 by bolts. The annular cover plate 7 and the annular recess 6 form the limiting structure to support the rotation of the second ring body 4. The first ring body 3 has support rods 8 connected to the two opening blades 1 on opposite sides. The support rods 8 pass through the first ring body 3 and can slide freely in the axial direction. The outer wall of the support rod 8 is provided with external threads, and a screw sleeve 9 is sleeved on it through the external thread. The annular recess 6 is provided with a groove 10 to accommodate the screw sleeve 9. The screw sleeve 9 can rotate freely in the groove 10. The bottom surface of the second ring 4 is connected to the threaded sleeve 9 by a snap-tooth engagement (not shown in the view). When the second ring 4 rotates, it can push the threaded sleeve 9 to rotate. The outer wall of the support rod 8 is provided with a limiting groove 11 that runs through the axis. The first ring body 3 is provided with a limiting protrusion 12 that inserts into the limiting groove 11. That is, when the second ring body 4 rotates, the support rod 8 remains radially fixed under the cooperation of the limiting groove 11 and the limiting protrusion 12. The screw sleeve 9 rotates and pushes the support rod 8 to slide along the axis, thereby driving the two spreading blades 1 to move inward or outward synchronously. The second ring 4 can be driven by a corresponding driving device set on the first ring 3. Specifically, a stepper motor is set on the first ring 3 and fixed on the first ring 3. Its drive shaft can be connected to a drive gear. A gear ring that cooperates with the drive gear can be set on the second ring 4. Its position locking method is controlled by the stepper motor.

[0033] The drainage tube 13 is made of medical-grade silicone, with an inner diameter of 4mm and multiple side holes at the front end. The tube body integrates a miniature intracranial pressure sensor 14 (model: ICP-PROBE, accuracy ±1mmHg), a miniature flow sensor 15 (model: SLF3S-1300F, range 0-50mL / h), and an optical viscosity detection unit; Specifically, the miniature intracranial pressure sensor 14 is embedded in the front side wall of the drainage tube 13, in direct contact with the drainage fluid, and is protected by a waterproof and breathable membrane. The miniature flow sensor 15 is a thermal type, installed in the middle section of the drainage tube 13, approximately 50 mm from the front end. The optical viscosity detection unit includes an LED light source 16 (wavelength range 500-650 nm) and a photodetector 17 (model: TSL257), installed on opposite sides of the drainage tube 13, 80 mm from the front end, and sealed by a light-transmitting window. The tail end of the drainage tube 13 is connected to the inlet of the intelligent pump control module, and the sensor cables are laid along the outer wall of the drainage tube 13, converging at the waterproof connector at the tail end.

[0034] The drainage tube 13 can be fixed to the annular cover plate 7.

[0035] The lumbar reference pressure sensor is independently installed in the subarachnoid space of the lumbar spine, using the same model as the miniature intracranial pressure sensor 14 (ICP-PROBE), and is connected to the main controller via an extension cable.

[0036] The intelligent pump control module includes a peristaltic pump and a precision proportional valve; Specifically, the peristaltic pump uses a stepper motor driven by an L298N motor driver (with a step angle range of 1.5-1.8°), paired with a standard three-roller pump head and silicone tubing (4mm inner diameter). It features forward and reverse rotation, enabling liquid suction and injection (flow rate adjustment range 0-50mL / h). A precision proportional valve (model: PVQ31) is connected in series with the peristaltic pump, with a response time ≤50ms, serving as an auxiliary adjustment mechanism and emergency braking device. A bubble detection sensor (model: AD-101) is installed in the downstream pipeline to monitor for air bubbles within the pipeline.

[0037] The main controller uses an STM32F407 microcontroller (168MHz main frequency, three 12-bit ADCs, multiple PWM output channels), featuring multi-channel ADC, PWM output, and interrupt handling functions. The main controller is electrically connected to the miniature Doppler probe 2, miniature intracranial pressure sensor 14, miniature flow sensor 15, optical viscosity detection unit, lumbar spine reference pressure sensor, and intelligent pump control module. The main controller also connects to a touchscreen display (7-inch, 1024×600 resolution) and an audible and visual alarm (buzzer + red LED) for parameter setting, status display, and abnormal alarms.

[0038] Example 2 This embodiment provides a control method for an intelligent expansion and drainage device based on the device of Embodiment 1. The method is automatically executed by the main controller and includes the following steps: Step S1: Pressure equalization initialization The main controller reads the intracranial pressure value P1 from the miniature intracranial pressure sensor 14 and the spinal canal pressure value P2 from the lumbar reference pressure sensor at a sampling rate of 50Hz, and calculates the pressure difference ΔP = P1 - P2. If |ΔP| > 2 mmHg (preset threshold), a pressure equalization operation is performed. When ΔP>0 (intracranial pressure is higher than spinal canal pressure), a PWM control signal is sent to the intelligent pump control module to start the peristaltic pump for forward low-speed drainage (10 rpm, corresponding to a flow rate of about 5 mL / h). At the same time, the decrease of P1 is monitored in real time, and the control command is updated every 100 ms until |ΔP|≤2 mmHg. When ΔP<0 (intracranial pressure is lower than spinal canal pressure), a control signal is sent to the intelligent pump control module to start the peristaltic pump to infuse artificial cerebrospinal fluid into the cavity at a low speed in the reverse direction (rotation speed 8 rpm, corresponding to a flow rate of about 4 mL / h), while monitoring the rise of P1 in real time until |ΔP|≤2 mmHg.

[0039] This step ensures that the pressure in the cranial cavity and spinal canal is basically balanced before the dura mater is cut, laying the foundation for subsequent stepwise release. Clinical trials have shown that after adopting this step, the average pressure difference before dural incision decreased from 8.5±2.3 mmHg in traditional surgery to 1.2±0.6 mmHg.

[0040] Step S2: Stepped release control Upon receiving a trigger signal indicating dural incision (which can be input by the physician via a touchscreen display or automatically identified by the main controller based on pressure changes), the main controller enters a high-speed sampling mode, increasing the sampling rate to 200Hz to monitor the rate of intracranial pressure decrease in real time.

[0041] If s > 5 mmHg / s (a preset safety threshold derived from clinical big data statistics), a shut-off signal is immediately sent to the precision proportional valve, driving it to completely clamp the tubing within 50 ms and triggering an audible and visual alarm. The event is recorded simultaneously for postoperative analysis.

[0042] Once the pressure stabilizes (s remains below 2 mmHg / s for more than 3 seconds), a control signal is sent to the peristaltic pump to initiate the forward and reverse pulse infusion mode. The specific parameters for this mode are: forward pulse speed 40 rpm, duration 0.5 seconds; reverse pulse speed 20 rpm, duration 0.2 seconds; pulse interval 1 second; cycle 10 times. Data from the optical viscosity detection unit is read after each pulse to evaluate the anti-clogging effect.

[0043] During execution, the main controller adjusts the speed of the peristaltic pump (P=0.8, I=0.1, D=0.05, control cycle 200ms) through a closed-loop PID algorithm based on the real-time flow rate data fed back by the micro flow sensor 15, ensuring that the deviation between the actual flow rate and the set value (input by the physician through the touch screen or automatically generated according to the preset drainage curve) is less than ±0.5mL / h.

[0044] This procedure reduces the rate of intracranial pressure decrease at the moment of dural incision from an average of 12.5 mmHg / s in traditional surgery to 3.2 mmHg / s (based on clinical data from 20 cases), effectively preventing brainstem displacement and cerebellar herniation.

[0045] Step S3: Gradient Closure Control Upon receiving a trigger signal indicating the end of surgery (which can be input by the physician via a touchscreen display), the main controller initiates a gradient shut-off mode. This mode gradually reduces the opening of the precision proportional valve (linearly decreasing from 100% to 0%, in steps of 1% / second), causing the drainage rate to linearly decrease to zero within 10 minutes, while continuously monitoring intracranial pressure fluctuations. Once the drainage rate has decreased to zero and the intracranial pressure has stabilized within the normal range (5-15 mmHg) for more than 30 seconds, the drainage tube 13 is completely shut off, and an audible alert is issued.

[0046] After adopting this procedure, the average intracranial pressure rebound amplitude in the 20 patients was 2.1±0.8 mmHg, while the rebound amplitude in the traditional sudden clamping group was 6.8±1.5 mmHg, showing a significant difference.

[0047] Step S0: Vascular avoidance control Before or simultaneously with step S1, the main controller receives the blood flow signal (sampling rate 1kHz) acquired by the miniature Doppler probe 2, extracts the blood flow features (velocity, direction, pulsatility index) after filtering and FFT transformation, and generates an augmented reality overlay image of the blood vessel avoidance zone on the touch screen (highlighting the blood vessel area in red). When the impedance sensor of the expanding blade 1 detects a sudden increase in opening resistance (resistance value exceeding a preset threshold of 3N) and the Doppler signal characteristics change (high-frequency pulsation component appears), it is determined that the blade has contacted a blood vessel, automatically stops opening, and issues an audible and visual alarm.

[0048] This step improved the accuracy of blood vessel identification from 65% (which relied on experience) to 98%, and no vascular injury events occurred in 20 surgeries.

[0049] Example 3 This embodiment further optimizes the parameter adjustment method for the positive and negative pulse perfusion modes based on Embodiment 2.

[0050] The main controller dynamically adjusts the pulse parameters based on the real-time viscosity data fed back by the optical viscosity detection unit (which detects changes in transmitted light intensity via photodetector 17 and converts the data into relative viscosity using a calibration curve). When the liquid viscosity is less than 1.5 times that of physiological saline, the standard parameters are as follows: forward pulse speed 30 rpm, duration 0.4 seconds; reverse pulse speed 15 rpm, duration 0.2 seconds; pulse interval 1 second. When the fluid viscosity is between 1.5 and 2.5 times that of physiological saline, increase the pulse intensity: positive pulse speed 40 rpm, duration 0.6 seconds; reverse pulse speed 20 rpm, duration 0.25 seconds; pulse interval 1 second; When the fluid viscosity is greater than 2.5 times that of physiological saline (indicating the presence of blood clots or high protein accumulation), a high-intensity pulse is used: forward pulse speed 50 rpm, duration 0.8 seconds; reverse pulse speed 25 rpm, duration 0.3 seconds; pulse interval 0.8 seconds.

[0051] Simultaneously, the main controller calculates the pulse efficiency η=(Q1-Q2) / Q2×100% based on the flow sensor data before and after the pulse, where Q2 is the average flow rate before the pulse and Q1 is the average flow rate within 10 seconds after the pulse. If η<20%, the pulse intensity is automatically increased by one level, and the number of cycles is increased to 15; if η>80%, the current parameters are maintained.

[0052] After dynamic adjustment, the drainage tubes in 13 of the 20 surgical cases were unobstructed throughout the entire procedure without any blockage, while in the fixed parameter control group (10 cases), 2 cases experienced temporary blockage (requiring manual flushing).

[0053] Example 4 To verify the technical effectiveness of this invention, 40 patients undergoing secondary surgery for cerebellar tonsillar herniation and syringomyelia were randomly divided into an experimental group (n=20, using the device and method of this invention) and a control group (n=20, using a traditional retractor and conventional drainage device). All surgeries were performed by the same group of physicians, and relevant indicators were recorded.

[0054] Patient inclusion criteria: age 18-65 years; confirmed by MRI with malformation and syringomyelia; previous posterior fossa decompression surgery with recurrent symptoms; consent to participate in the study. Exclusion criteria: other intracranial lesions; severe cardiopulmonary dysfunction; coagulation disorders.

[0055] Key observation indicators: incidence of vascular injury, maximum rate of intracranial pressure decrease during dural incision, drainage tube blockage rate, postoperative hospital stay, and incidence of cerebrospinal fluid leakage.

[0056] Results (see table below): The technical solution significantly reduces the risk of vascular injury and drainage tube blockage rate during secondary posterior cranial surgery, effectively suppresses pressure oscillations during dural incision, and shortens postoperative recovery time, demonstrating significant clinical advantages.

[0057] This invention provides an intelligent dilation and drainage device and its control method for posterior cranial surgery in neurosurgery. It can be widely applied to posterior cranial fossa surgery in neurosurgery, especially in complex cases involving severe tissue adhesions and unclear anatomical structures during secondary surgeries. The device is compact, precisely controlled, and easy to operate, possessing significant clinical application value and industrialization prospects.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An intelligent dilation and drainage device for posterior cranial surgery in neurosurgery, characterized in that: include: The expansion module includes a pair of expansion blades, the front end of which is embedded with a miniature Doppler probe for identifying the location of blood vessels during surgery; The drainage tube has its front end located between the spreading blades, and the tube body integrates a miniature intracranial pressure sensor, a miniature flow sensor, and an optical viscosity detection unit. The lumbar reference pressure sensor is independently installed in the subarachnoid space of the lumbar spine to obtain reference values ​​of spinal canal pressure. The intelligent pump control module includes a peristaltic pump and a precision proportional valve. The peristaltic pump has forward and reverse rotation functions to realize the suction and injection of liquid. The main controller is electrically connected to the miniature Doppler probe, the miniature intracranial pressure sensor, the miniature flow sensor, the optical viscosity detection unit, the lumbar spine reference pressure sensor, and the intelligent pump control module, respectively. The main controller is configured to execute the following control logic: Before cutting the dura mater, the intelligent pump control module is controlled to perform pre-inflation or pre-drainage based on the difference between the miniature intracranial pressure sensor and the lumbar spine reference pressure sensor, so that the pressure in the cranial cavity and the spinal canal reaches a balanced state. At the moment the dura mater is cut, the rate of intracranial pressure decrease is monitored in real time. When the rate of decrease exceeds the preset safety threshold, the drainage tube is automatically clamped. During the drainage process, the peristaltic pump is controlled to execute a forward and reverse pulse perfusion mode. Through alternating forward suction and reverse push, liquid pulse waves are generated to flush the side holes and cavity walls of the drainage tube.

2. The intelligent dilation and drainage device for posterior cranial surgery in neurosurgery according to claim 1, characterized in that: The main controller is also configured to: During the expansion process, an augmented reality overlay image of the blood vessel avoidance zone is generated on the display screen based on the blood flow signals acquired by the micro Doppler probe. When the impedance sensor of the blade detects a sudden increase in opening resistance and a change in Doppler signal characteristics, it determines that the blade has contacted a blood vessel and automatically stops opening and issues an alarm.

3. The intelligent dilation and drainage device for posterior cranial surgery in neurosurgery according to claim 1, characterized in that: The specific parameters of the forward and reverse pulse perfusion mode are as follows: forward pulse speed 30-50 rpm, duration 0.3-0.8 seconds; reverse pulse speed 15-25 rpm, duration 0.1-0.3 seconds; pulse interval 0.5-2 seconds; number of cycles 5-15.

4. The intelligent dilation and drainage device for posterior cranial surgery in neurosurgery according to claim 1, characterized in that: The main controller is also equipped with a gradient shut-off mode: before closing the drainage at the end of the operation, the drainage resistance is gradually increased so that the drainage rate linearly decreases to zero within 5-15 minutes, while monitoring intracranial pressure fluctuations.

5. The intelligent dilation and drainage device for posterior cranial surgery in neurosurgery according to claim 1, characterized in that: It also includes external support equipment, which is a multi-degree-of-freedom robotic arm.

6. The intelligent dilation and drainage device for posterior cranial surgery in neurosurgery according to claim 1, characterized in that: The optical viscosity detection unit (23) includes an LED light source (231) and a photoelectric receiver (232), which are installed on both sides of the drainage tube (2) to monitor the viscosity of the drainage liquid in real time. The main controller (5) compensates and corrects the pulse perfusion parameters based on the viscosity data.

7. The intelligent dilation and drainage device for posterior cranial surgery in neurosurgery according to claim 1, characterized in that: The safety threshold is set to an intracranial pressure drop rate >5 mmHg / s. When this threshold is exceeded, the main controller drives the precision proportional valve to completely clamp the pipeline within 50 ms and triggers an audible and visual alarm.

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