26 results about "Vascular flow" patented technology

Systems and methods are described for modulating blood flow through a blood vessel. Devices may include one or more implantable devices comprising an expandable frame comprising a proximal end and a distal end and a longitudinal axis extending therethrough; a membrane comprising an inflow end and an outflow end, wherein the inflow end is at least partially installed within the distal end of the expandable frame; an actuator coupled to a control wire, the control wire being coupled to a portion of the membrane; a first magnet configured to induce rotation of the actuator to actuate the control wire to activate application of tension to the control wire and cause the membrane to radially collapse at the outflow end; and a second magnet configured to generate a changing magnetic field pole direction to cause rotation of the first magnet to cause the membrane to radially expand at the outflow end.

The invention relates to the technical field of image processing, and discloses an interventional navigation method and system based on multi-modal image fusion. The method comprises the following steps: segmenting CT angiography data to form a three-dimensional vascular skeleton model, calculating MRI perfusion data to generate a vascular flow velocity field, and constructing a vascular geometric constraint matrix; performing diffusion reconstruction on the constraint matrix and the instrument position information, and outputting an instrument motion prediction track; estimating the postures of the tips of the X-ray perspective imaging instruments to form instrument-blood vessel space correlation features; safety navigation constraint parameters are generated through distance field calculation; and generating a real-time navigation instruction containing a propulsion distance and a rotation angle by adopting a path planning algorithm. The technical problems that in a traditional interventional navigation system, multi-modal image data fusion is insufficient, instrument motion prediction is inaccurate, and a safety constraint mechanism is incomplete are solved, and the precision, safety and real-time performance of interventional operation navigation are improved.

The embodiment of the present application discloses a method and computer device for determining blood vessel flow velocity. The method includes: acquiring angiography sequence images, finding a coronary angiography image that meets the best development conditions in the angiography sequence images as the best coronary angiography image, selecting the coronary angiography image arranged before the timestamp of the best coronary angiography image in the angiography sequence images in sequence as the target coronary angiography image, the target coronary angiography image and the best coronary angiography image forming an image segmentation set, generating a blood vessel length change graph based on the image segmentation set, determining the conduction start time and the conduction end time based on the blood vessel length change graph, and determining the blood vessel flow velocity based on the main branch vessel length, the conduction start time and the conduction end time. The embodiment of the present application does not need to analyze all coronary angiography images, and selects the best coronary angiography image and the target coronary angiography image arranged before the best coronary angiography image for analysis, which can reduce the number of blood vessel segmentations.

The application relates to the technical field of image processing, and discloses an interventional navigation method and system based on multi-modal image fusion. The method comprises the following steps: CT angiography data is segmented to form a three-dimensional vascular skeleton model, MRI perfusion data is calculated to generate a vascular flow field, and a vascular geometric constraint matrix is constructed; the constraint matrix and instrument position information are diffused and reconstructed, and an instrument motion prediction trajectory is output; an X-ray fluoroscopy image instrument tip posture is estimated, and instrument-vascular spatial correlation features are formed; safe navigation constraint parameters are calculated and generated through a distance field; and a path planning algorithm is used to generate real-time navigation instructions containing a pushing distance and a rotation angle. The application solves the technical problems of insufficient multi-modal image data fusion, inaccurate instrument motion prediction and imperfect safety constraint mechanism in a traditional interventional navigation system, and improves the precision, safety and real-time performance of interventional surgery navigation.

A method for characterizing a blood vessel includes receiving anatomical information of the blood vessel and receiving four-dimensional flow data of multiple blood vessels from multiple subjects. The method further includes, using the four-dimensional flow data to train a flow model to determine blood vessel properties, and using the anatomical information of the blood vessel as an input to the trained flow model to estimate one or more properties of the blood vessel.

A method of producing an arteriovenous (AV) fistula includes producing an anastomosis between a primary blood vessel (e.g., a vein) and a secondary blood vessel (e.g., an artery). A collateral (or competing) blood vessel in fluid communication with one of the primary blood vessel or the secondary blood vessel is identified. A reversible flow restrictor is then applied to the collateral blood vessel to reduce a blood flow rate through the collateral blood vessel. In some embodiments, the anastomosis can be produced percutaneously. In some embodiments, the reversible flow restriction (or a portion thereof) can be removed from the collateral blood vessel. In other embodiments, the reversible flow restriction (or a portion thereof) can be adjusted to allow increased blood flow therethrough while within the collateral blood vessel.

A self-expanding implant for use as a vascular flow reducer is disclosed having a variable mesh angle to limit the amount of diameter variation of certain portions of the implant, such as an hourglass-shaped laryngeal section or central laryngeal inner diameter. Methods of making such implants are also described.

Self-expanding implants useful as vascular flow reducers are disclosed with minimized wall porosity configured to maximize the percentage of total vascular flow routed through the reduced orifice while maintaining an overall stable structure that avoids or minimizes distortions such as in-folding when the implant is compressed to a smaller diameter suitable for delivery through the vasculature to the treatment site.

Implant devices are provided for restoring compliance characteristics to blood vessels. An exemplary implant device includes an outer tubular frame having a diameter than varies along a longitudinal axis and a radially expandable tube disposed within the frame. Further disclosed are implant devices including a frame having an axially convex form that expands in diameter moving from first and second axial ends of the frame to a medial portion of the frame, and a cylindrical toroidal balloon member comprising one or more gas-filled chambers disposed at least partially within the frame. Further disclosed are implant devices including a tubular frame comprising a first axial segment and a second axial segment, a radially expandable tube disposed within the first axial segment of the frame, and a one-way valve disposed within the second axial segment of the frame.

The utility model discloses a blood vessel flow restrictor which comprises a clamping rod, the clamping rod comprises a holding rod part, an upper forceps rod part and a lower forceps rod part, a pressing ring assembly is arranged at one end of the upper forceps rod part, and a pressing plate is arranged at one end of the lower forceps rod part; the adjusting mechanism comprises a first sliding block arranged on the upper forceps rod part in a sliding mode, a second sliding block arranged on the lower forceps rod part in a sliding mode, a screw rod and an annular rope. The pressing ring assembly is structurally formed by connecting the two U-shaped rods in a sleeved mode, the two U-shaped rods are contracted by moving the sliding block to pull the annular rope, adjustment can be carried out according to the size of a focus, treatment of a patient is facilitated, a rotary knob on the screw can be rotated, the distance between the two forceps rod parts of the clamping rods can be adjusted, and flexible use can be achieved.

System and method for deploying a flow restriction device in patient vascular and recapturing and repositioning the flow device after full or partial deployment. Disclosed systems and methods permit confirmation of device placement, such as by measuring a pressure drop across the partially or fully deployed device in the coronary sinus before release of the device and permanent implantation.

This invention discloses an automatic liver segmentation method and system based on anatomical prior guidance of vascular flow direction, belonging to the fields of medical image processing, computer-aided diagnosis, computer vision, and artificial intelligence. The method includes acquiring liver medical images and vascular flow direction features, constructing a three-dimensional vascular direction vector field and vascular topology map, and extracting vascular anatomical prior features using a graph convolutional network; enhancing key vascular region features by combining an attention mechanism and fusing them with liver image features; outputting a liver segment probability map through a decoding network; training the model based on cross-entropy loss, boundary alignment loss, and region consistency loss to achieve end-to-end optimization; and finally outputting the liver segmentation result, which can be used for medical image visualization and surgical planning assistance. This invention improves the accuracy, robustness, and anatomical consistency of liver segmentation, and has good clinical application value.

The present invention relates to the technical field of vascular model instruments. Disclosed in the present invention is an intelligent cardiovascular hemodynamic simulation device. The following solution is provided: the intelligent cardiovascular hemodynamic simulation device comprises a vascular flow model, wherein a hemodynamic controller is provided at the bottom of the vascular flow model, and a model display stand is fixedly connected to the bottom surface of the vascular flow model; and the vascular flow model comprises a silicone base trunk. In the technical solution of the present invention, the display height and angle of the model are adjusted by means of the model display stand, such that when the model is observed and learned, an observer can obtain a better observation field of view; moreover, the implantation of a latex vascular system into a transparent silicone human body model can allow the observer to more clearly observe a blood flow process, and to simultaneously use the hemodynamic controller to control the flow velocity and flow rate of liquid in blood vessels, thereby intelligently simulating blood flow situations in the blood vessels under different exercise intensities.

The utility model relates to the field of vascular surgical instruments, in particular to a vascular flow restrictor for high-flow internal fistula, which comprises a body made of flexible materials, the length size and the width size of the body are at least two times of the thickness size of the body, and the length size and the width size of the body are at least two times of the thickness size of the body. A plurality of parallel first scale marks are arranged on the body at intervals in the width direction, the body can wrap the blood vessel in the width direction, and the two sides of the body are connected to compress the blood vessel. According to the blood vessel flow limiter, a large contact area can be formed between the body and a blood vessel, uniform acting force can be applied to the blood vessel, the effect of protecting the blood vessel can be achieved, and the problem that the blood vessel is easily cut due to the fact that the contact area between a suture and the blood vessel is too small and the pressure intensity per unit area is too large is solved; in addition, the diameter or radius of the blood vessel can be estimated or measured through the scale marks arranged on the surface of the body, and compared with visual size estimation, measurement through the scale marks is more visual, and the measurement precision is higher.

The present invention discloses a method and system for angiographic image enhancement for radiological examinations. The method comprises the steps of angiographic image collection, vascular flow pattern coding, dynamic decoupling of blood and bone, reconstruction of vascular edges, and image enhancement. The present invention relates to the technical field of angiographic image enhancement, and specifically to a method and system for angiographic image enhancement for radiological examinations. Regarding vascular flow pattern coding, a multiphase time-series guided coding mechanism is proposed. A dynamic decoupling method for vascular bone structure combined with adversarial feature separation is employed to perform dynamic decoupling of blood and bone, effectively isolating dynamic perfusion components from static high-density bone background signals. Dynamic information is decoupled from bone background interference, further reconstructing vascular edges and improving image contrast and structural integrity.

A flow restrictor for a blood vessel can include a frame positionable within a blood vessel, and a leaflet or flap comprising an inflow end and an outflow end. The inflow end of the leaflet or flap can be configured to move (optionally using a control element) in response to a first increase in a blood pressure within the blood vessel, and in response to the blood pressure being within a first blood pressure range. The flow restrictor can be further configured to be a bi-modal flow restrictor, wherein the leaflet or flap can be configured to collapse or prolapse in response to the blood pressure being within a second blood pressure range. In some cases, the bi-modal flow restrictor can include an inner valve configured to move with respect to the frame in response to the blood pressure being within the second blood pressure range.

Self-expanding implants useful as vascular flow reducers are disclosed with minimized wall porosity configured to maximize the percentage of total vascular flow routed through the reduced orifice while maintaining an overall stable structure that avoids or minimizes distortions such as in-folding when the implant is compressed to a smaller diameter suitable for delivery through the vasculature to the treatment site.

The present invention relates to the technical field of biomedicine, and particularly relates to a vascular flow simulation device for a systemic / pulmonary double circulation system based on hydraulic drive. It includes a systemic circulation simulation area, a pulmonary circulation simulation area, and a cardiac pulsation simulation area; by controlling solenoid valve I, solenoid valve II, solenoid valve III, solenoid valve IV, solenoid valve V, and solenoid valve VI, the cardiac pulsation simulation area simulates the blood pressure conditions during the isovolumetric contraction period, rapid ejection period, slow ejection period, pre-diastolic period, and diastolic period of the heart, and changing the switching frequency of the solenoid valve can change the simulated heart rate; at the same time, the systemic circulation simulation area is used to simulate the systemic circulation of the human body, and the pulmonary circulation simulation area is used to simulate the pulmonary circulation of the human body. Therefore, the present invention studies the situation when the systemic circulation and the pulmonary circulation interact. In addition, the present invention uses one power source to achieve the drive control of the systemic circulation and the pulmonary circulation, avoiding the problem that it is difficult for two power sources to be synchronized.

A method for detecting biometric parameters includes the steps of performing a bone graft procedure on at least one vertebra of a spine, providing at least one biometric sensor at the at least one vertebra, the sensor measuring at least one parameter selected from the group consisting of pressure, tension, shear, relative position, and vascular flow in an adjacent surrounding, and measuring the at least one biometric parameter at the vertebra with the sensor.

A self-expanding implant useful as a vascular flow reducer is disclosed. This implant has a variable cell angle and limits the amount of diameter change in a specific part of the implant (e.g., the throat or the inner diameter of the central throat of an hourglass shape). A method for fabricating such an implant is also described.

A method and system for monitoring ultrasound tests and generating images to visually summarize the test results, are described. The method includes receiving ultrasound test data representing blood flow in a blood vessel of several interconnected blood vessels of a brain, and determining, based on the ultrasound test data, a direction and one or more hemodynamic values at a location in the blood vessel. An image of the interconnected blood vessels of the brain is generated. The image includes a direction indicator corresponding to the direction and a hemodynamic indicator corresponding to the one or more hemodynamic values. A user may view the image to assess whether the blood flow in the blood vessel is normal. Other embodiments are also described and claimed.

This invention relates to a vascular flow restrictor, comprising: a tubular body, a first fixing member, and at least one second fixing member; the tubular body includes an inflow end and an outflow end; the inflow end is provided with a first opening, and the outflow end is provided with a second opening, the continuous cavity defined between the first opening and the second opening forming a hollow cavity of the tubular body; the outflow end of the tubular body is constricted into at least two connecting bundles, the connecting bundles being fixed by the first fixing member or the second fixing member; the first fixing member has a connecting portion for connecting with an external connecting member; the second fixing member has a communicating hole for the external connecting member to pass through. The vascular flow restrictor of this invention, by constricting the outflow end into at least two connecting bundles, creates a tapered structure in the hollow cavity, reducing the blood flow rate, and allowing the connection of at least two connecting bundles to be achieved with a single connecting member, thus reducing the required inner diameter of the delivery sheath.

Described herein is a microfluidic assay device that mimics in vitro the in vivo biological environment, supporting endothelization, allowing for perfusive flow similar to in vivo blood flow conditions, and providing for realistic interactions between T-cells and solid tumor cells, such as glioblastoma multiforme tumor cells. Also described herein are methods of using this microfluidic assay device for the study of interactions of immune cells with tumor cells, such as glioblastoma multiforme tumor cells, and the development of improved immunotherapeutic approaches against cancers, such as glioblastoma multiforme.

A diagnostic system includes one or more blood flow sensors adapted to contact but not penetrate the skin of the pedal arch and aligned with blood vessels of the pedal arch. Readings from the blood flow sensors are transformed into blood flow acceleration times, and the blood flow acceleration times are used to identify a blood flow pathology.

Described herein is a microfluidic assay device that mimics in vitro the in vivo biological environment, supporting endothelization, allowing for perfusive flow similar to in vivo blood flow conditions, and providing for realistic interactions between T-cells and solid tumor cells, such as glioblastoma multiforme tumor cells. Also described herein are methods of using this microfluidic assay device for the study of interactions of immune cells with tumor cells, such as glioblastoma multiforme tumor cells, and the development of improved immunotherapeutic approaches against cancers, such as glioblastoma multiforme.

Systems and methods are disclosed for providing intraprocedural guidance and feedback during a vascular intervention via intraprocedural Doppler ultrasound performed on one more distal peripheral vessels impacted by the vascular intervention. According to various example embodiments, intraprocedural Doppler ultrasound is performed to detect the changes in flow characteristics and / or anomalous vascular flow signatures of the peripheral vasculature impacted by the intervention, such as the detection of an adverse vascular event. The detected changes in flow characteristics are intraprocedurally communicated to guide and / or assist clinical decision making, and / or employed to autonomously send control signals to interrupt or modify treatment. In other embodiments, intraprocedural guidance and / or feedback is autonomously provided during a neuromodulation procedure via Doppler ultrasound performed on one more peripheral vessels for which blood flow is modulated by the neuromodulation procedure, with the neuromodulation device optionally being controlled according to the detected changes in blood flow.