11 results about "Main vessel" patented technology

The present invention relates to a device (1) for reducing a particle density of a sample of a suspension of particles in a liquid, the device comprising a measurement flow path (13) for characterizing the sample of the suspension, wherein the device (1) is configured to withdraw a sample of the suspension residing in a main vessel (100), and to dilute the sample, particularly when a measure indicative of the particle density in the sample is above a pre-defined threshold.

This application provides a method and apparatus for determining blood flow velocity in a blood vessel, comprising: acquiring an initial contrast image and a target contrast image after injecting a contrast agent; comparing the initial contrast image and the target contrast image to determine the length of the blood vessel through which the contrast agent flows; determining the uniformity of the contrast agent in the main vessel region and / or the visualization of microvessels in the background region of the target contrast image based on the contrast agent concentration in the target contrast image; correcting the blood vessel length based on the uniformity of the contrast agent and / or the visualization of microvessels to obtain a corrected blood vessel length; and determining the blood flow velocity based on the corrected blood vessel length. This reduces calculation errors caused by the imaging angle of the contrast image, the shape of the blood vessel, or blood vessel bifurcation, thereby improving the accuracy of blood flow velocity assessment.

A bifurcated intravascular stent graft comprises primary stent segments and a primary graft sleeve, forming a main fluid channel and having a side opening therethrough. An external graft channel formed on the primary graft sleeve has a first end communicating with the side opening and an open second end outside the primary graft sleeve, thereby providing a branch flow channel from the main channel out through the side opening and external graft channel. The primary stent segments and graft sleeve engage an endoluminal surface of a main vessel and form substantially fluid-tight seals. The stent graft further comprises a secondary stent graft, which may be positioned partially within the external graft channel, through the open second end thereof, and partially within a branch vessel. The secondary stent graft engages the inner surface of the external graft channel and the endoluminal surface of the branch vessel, thereby forming substantially fluid-tight seals.

The application relates to a coronary microcirculation vascular resistance acquisition method and system based on a layered myocardial model, which comprises the following steps: establishing a coronary vessel model from medical images; generating a side vessel for the coronary artery; regarding the coronary artery and the side vessel as main vessels, fitting and constructing an outer surface of a myocardial model according to the outlet position of the main vessels, establishing an inner surface of the myocardial model based on a similar principle to the outer surface, and ensuring that the volume of the model is the myocardial volume value; using an ellipsoid surface for layered interpolation; selecting a point P in the outermost layer and connecting the main vessel outlet to generate a microcirculation vessel; selecting a point T outside the current layer and cooperating with the nearest microcirculation vessel to generate a bifurcated microcirculation vessel; gradually advancing to the inner layer to form bifurcation and ensure the bifurcation number of each layer; and calculating the resistance value of the main vessel outlet. Compared with the prior art, the application considers the distribution of the coronary artery at various levels of the myocardium under real conditions, so that the calculated resistance value is more accurate and has the specificity of a patient.

The water treatment system comprises a main container (12) defining an interior and having an upper edge (16); a reservoir (16) removably inserted into the interior and located on the upper edge, the reservoir defining a cartridge seat (18) comprising a plurality of apertures (20) in communication with a helical thread (22) and an annular platform (24) vertically depending from the thread; a filter cartridge (10) including a cap (28) associated with a sump body (30) and having filter media (42) in the sump body, the cap having a plurality of radially outwardly protruding pins (48) configured and arranged for engaging the apertures and helical threads; and an annular seal (50) disposed on the exterior of the sump body and spaced below the cap. The filter cartridge and cartridge seat are configured such that when the cap pin engages the helical thread, the seal is pressed against the annular platform upon reaching a fully engaged position of the cap in the thread.

The application relates to a method and system for obtaining coronary end microcirculation vascular resistance based on vascular growth, and the method comprises the following steps: acquiring medical images, and extracting a myocardial model and a coronary vascular model respectively; generating collateral vessels in the coronary vascular model; regarding all coronary vessels and collateral vessels as main vessels, and obtaining the position coordinates and the vascular radius; randomly selecting a point P in the myocardial model, connecting the point P with the outlet of the main vessel, and generating microcirculation vessels for each outlet of the main vessel; randomly selecting a point T in the point cloud file of the myocardial model, connecting the point T with the nearby microcirculation vessels, and generating multiple bifurcated microcirculation vessels, until the radius of all vessel outlets in the generated vascular tree is smaller than a preset vascular threshold; and calculating the resistance value of each outlet of the main vessel. Compared with the prior art, the coronary end microcirculation vascular resistance value calculated based on the reestablished microcirculation vascular model is more accurate and has the specificity of patients.

This invention provides a method and apparatus for identifying retinal vein beads. One embodiment of the method includes: first, performing vascular segmentation processing on a target fundus image to output segmented vein vessels; wherein, the segmented vein vessels include main vessels and branch vessels; second, generating a diameter feature map based on the diameter feature sequence corresponding to the main vessels and / or the branch vessels; finally, if the graphic features of the diameter feature map meet preset conditions, determining that retinal vein beads exist on the segmented vein vessels. Therefore, this embodiment of the method can automatically identify retinal vein beads based on fundus images, helping to improve the accuracy of retinal vein bead identification, providing a reference for disease diagnosis and treatment, and contributing to improving the scientificity and accuracy of clinical decision-making.

This invention belongs to the field of vascular recognition technology, specifically relating to a method and system for retinal arteriovenous vessel recognition based on image recognition. The invention includes determining the structural features of a vascular path, including at least one of branch points and bending structures. In response to the determination of these structural features, the vascular path is classified into main vessels or branch vessels based on preset classification rules utilizing these features. This invention divides vascular nodes into a set of main control vascular points and a set of secondary control vascular points. Branch points are determined by calculating the offset of adjacent nodes of the main control vascular points, and bending structures are determined by calculating the introduced force based on the distribution of the secondary control vascular point set. This utilizes the different characteristics of the main control vascular point set and the secondary control vascular point set to differentiate between these two key topological structures—branch points and bending structures—avoiding the misjudgment of structures caused by treating all vascular nodes equally, thus improving the accuracy of structural feature recognition.

The invention belongs to the technical field of micro-catheters, and discloses an inner U-shaped double-cavity micro-catheter suitable for large-angle coronary bifurcation lesion, the inner U-shaped double-cavity micro-catheter comprises a catheter body, a first cavity and a second cavity are formed in the catheter body, a first through hole is formed in the side wall of the catheter body, and the first through hole is communicated with the second cavity; one end of the guide pipe body is connected with a connecting pipe comprising a first inlet pipe and a second inlet pipe; the end, away from the first through hole, of the second cavity communicates with the second inlet pipe. The end, close to the first through hole, of the catheter body is connected with an upper limiting piece and a lower limiting piece, the lower limiting piece is located between the upper limiting piece and the connecting pipe, a groove is formed in the upper limiting piece, part of the lower limiting piece is located in the groove, and the upper limiting piece and the lower limiting piece divide the end, close to the first through hole, of the second cavity into a U-shaped channel. The U-shaped channel is communicated with the first through hole; the problem that the guide wire is difficult to enter the bifurcated blood vessel due to the fact that the angle between the lesion bifurcated blood vessel and the main blood vessel is large is solved.

Methods for removing clot material by directional aspiration may include removing clot material from a side vessel while the suction catheter remains in the main vessel. These methods may include a steerable distal end region. In some cases the apparatuses and methods may include the use of a guide catheter and / or a guidewire in orienting the suction catheter to laterally capture clot material from a side vessel without having to enter the side vessel. Any of these methods may include optionally sensing and confirming clot material (e.g., electrically sensing).

The invention discloses a retinal blood vessel bifurcation angle determination method, system and device, a medium and a product, and relates to the field of medical image processing, and the method comprises the steps: carrying out the blood vessel segmentation of a retinal image, obtaining a binary image, and carrying out the fracture and cavity restoration to form a coherent image; respectively setting foreground and background pixels of the coherent image; traversing the coherent image, and deleting foreground pixels meeting a first set condition and a second set condition to obtain a blood vessel center line image; trimming the blood vessel center line image to obtain a blood vessel center line; based on the blood vessel center line and the calculation area, main blood vessels are selected in the supratemporal area and the subtemporal area respectively; and traversing the main blood vessel to obtain a blood vessel bifurcation point, and determining the diameter of the blood vessel, so as to determine the retina blood vessel bifurcation angle based on the blood vessel bifurcation point. According to the method, the influence of manual subjectivity can be effectively avoided, the determination efficiency is improved while the determination precision of the retinal blood vessel bifurcation angle is improved, and then the large-scale fundus screening requirement is met.