Noninvasive portal vein hemodynamic parameter measuring method

A technology of fluid dynamics and venous blood, applied in the fields of physiology, pathophysiology and clinical medicine, it can solve the problems of limited research scope, unestablished pressure distribution of portal venous system, and inability to directly quantitatively evaluate hemodynamic parameters.

Inactive Publication Date: 2014-10-22
SHANGHAI TONGJI HOSPITAL
View PDF5 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, its limitation is that CT angiography can only provide anatomical information to judge the shape, patency and collateral circulation of the hepatic portal vein, and cannot directly quantitatively evaluate hemodynamic parameters.
However, the various analysis techniques currently used are still unable to quantify the pressure indicators of the portal vein, and its expensive diagnostic costs also limit its clinical application to a certain extent.
[0011] To sum up, the currently commonly used techniques for detecting hemodynamic parameters of the portal vein system are affected by various interference factors, such as trauma, unquantified data, and large variability.
In addition, the deficiencies in the research on portal vein pressure detection at home and abroad are: the scope of research is limited to the main portal vein, and rarely involves the main branches of the portal system; the pressure measurement is limited to a certain part, and the overall pressure distribution of the portal vein system has not been established; Hemorheology research is still in its infancy, changes in blood viscosity and reduction in red blood cell deformability will change the resistance of portal vein vessels

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Noninvasive portal vein hemodynamic parameter measuring method
  • Noninvasive portal vein hemodynamic parameter measuring method
  • Noninvasive portal vein hemodynamic parameter measuring method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0057] Embodiment 1 establishes a geometric model

[0058] The enhanced CT images collected in the GE Medical Systems working platform were exported to dicom format, with a layer thickness of 1.250 mm, a total of 570 layers, an image resolution of 512 pixels × 512 pixels, and a pixel size of 0.797 mm. The picture is imported into the medical image control software MIMICS, and the software automatically calculates and generates a composite map of the two-dimensional plane (coronal plane, sagittal plane) of the portal vein system. According to the difference in CT values ​​between blood vessels and surrounding tissues, through threshold setting, tissues such as fat and muscle are extracted, and then the research scope is limited to obtain a preliminary three-dimensional model of the portal vein. Because the portal vein and its branches are difficult to separate directly from the surrounding tissues in the three-dimensional model, the MIMICS multi-layer editing operation was used...

Embodiment 2

[0059] Embodiment 2 establishes a mathematical model

[0060] Import the geometric model into the Flotran module of the fluid mechanics calculation software ANSYS, generate the volume file, and establish the numerical model. Use a plane perpendicular to the blood flow direction to intercept the blood vessel model to obtain the inlet and outlet. According to the finite element idea, the three-dimensional tetrahedron element is used to divide the mesh inside the blood vessel, with a total of 848,432 meshes and 150,796 computational nodes. In order to obtain the pressure and velocity distribution of the portal vein system, the three-dimensional vascular model is subjected to local mesh refinement to improve the calculation accuracy. Then, discrete initial boundary conditions were set: 1. The blood flow velocity at the vessel wall was 0 cm / s; 2. The main portal vein velocity was 15.8 cm / s; 3. The end pressure of the vessel outlet was 10 mmHg. Then, given the control parameters r...

Embodiment 3

[0061] Example 3 Acquisition and Analysis of Velocity and Pressure Profiles

[0062] After the calculation of the Flotran module of ANSYS is completed, the overall effect map of the velocity and pressure of the three-dimensional portal vein and its branches can be obtained. It can be seen that the pressure value of the portal venous system gradually decreases from the lower inlet (the superior mesenteric vein and splenic vein) to the upper outlet (the end of the portal vein enters the liver). Since the present invention is an in vitro simulation technology, it can rotate at multiple angles and observe the pressure distribution. In addition, we use the sagittal section perpendicular to the portal vein to obtain the velocity and pressure distribution map inside the vessel. Velocity distribution hints: from the confluence of the portal vein to the liver, the blood flow velocity gradually increases due to the narrowing of the vessel diameter; the velocity of the outer wall of the...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a noninvasive portal vein hemodynamic parameter measuring method which includes the steps of firstly, using a thin-section CT image to build a three-dimensional geometric model of a liver portal vein; secondly, using the finite element analyzing method of hydromechanics calculating software ANSYS to perform meshing on the geometric model and build a three-dimensional mathematic model; thirdly, calculating the hemodynamic parameter of the portal vein in an analog manner to obtain a speed and pressure distribution effect picture. The method is safe, noninvasive, simple to operate, visualized, quantized and high in accuracy, and the effective model is built for scientific researches and clinic services.

Description

technical field [0001] The invention belongs to the fields of physiology, pathophysiology and clinical medicine, and in particular relates to a method for measuring physiological parameters, and more particularly relates to a method for measuring portal vein hemodynamic parameters. Background technique [0002] In the current physiology, pathophysiology research, and clinical practice, there is still a lack of a safe, non-invasive, easy-to-operate, intuitive, quantitative, and highly accurate portal hemodynamic evaluation method and pressure parameter detection technology. Commonly used detection methods include invasive (such as: portal vein catheterization, B-ultrasound-guided percutaneous transhepatic portal vein puncture, intraoperative portal vein puncture) and non-invasive (such as: color Doppler ultrasound, CT angiography, magnetic resonance angiography, etc.) Contrast) two categories. [0003] Invasive Detection Technology [0004] 1. Portal vein catheterization:...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): A61B5/026
Inventor 杨长青祁小龙周方宇李功文
Owner SHANGHAI TONGJI HOSPITAL
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products