WO2019132048A1

WO2019132048A1 - Method for simulating choroidal blood flow

Info

Publication number: WO2019132048A1
Application number: PCT/KR2017/015428
Authority: WO
Inventors: 박건형; 이지은; 이종수
Original assignee: 부산대학교 산학협력단
Priority date: 2017-12-26
Filing date: 2017-12-26
Publication date: 2019-07-04

Abstract

The present invention relates to a method for simulating blood flow with respect to the circulation of choroid that is known as a mechanism of important diseases including macular degeneration, which is a major cause of blindness. The method for simulating choroidal blood flow according to the present invention comprises: a first step of generating a blood vessel bed by specifying a size of the blood vessel bed, a resistance of the inside and outside of a lobule, and an internal structure of the lobule; a second step of specifying arteries, wherein the specified arteries are numbered in a group; a third step of specifying veins, wherein the specified veins are numbered in a group; and a fourth step of analyzing a blood flow rate and indicating the blood flow and blood pressure inside and outside the blood vessels. Furthermore, when the blood vessel bed is generated in the first step, the blood vessel bed has hexagonal lobules formed therein, wherein resistance values inside and outside the lobules may be changed. Moreover, the blood pressure of the arteries of a group specified by the same number may be changed, and the blood pressure of the veins of a group specified by the same number may be changed. In the fourth step, blood flow analysis is conducted so as to represent a darker black color as the blood flow rate is smaller and a bright white color as the blood flow rate is greater, separately, in which the direction of the blood flow is indicated by an arrow, the thickness of the arrow indicating a blood flow rate.

Description

Simulation of the choroidal blood flow in the eye

The present invention relates to a method for simulating blood flow in intraocular choroidal vessels, which is a major cause of blindness and can resolve anatomical structure and function inconsistency regarding the circulation of choroid, which is known to be a cause of important diseases including macular degeneration.

The main part of the eyeball is formed as a layered structure of the retina, and when the intraocular tissues are structurally deformed, it develops as vision loss or severely blindness. According to the National Health Insurance Corporation, the number of patients with macular degeneration has nearly doubled from 7,631 in 2000 to 13,673 in 2004. In particular, age-related macular degeneration is the leading cause of blindness in developed countries.

Age-related macular degeneration is known to cause bleeding and scarring and severe visual impairment due to the abnormal choroidal neovascularization in the central macula due to the secondary choroidal vascular endothelial cell proliferation associated with choroidal blood flow abnormalities.

Choroids are complexly arranged three-dimensionally and have an anastomotic structure that connects blood vessels at various stages, making it difficult to analyze blood flow. The choroidal capillaries are arranged in the form of lobules (lobules), and the choroidal cavernous artery is connected to the central part of the robe. The blood flowing through the small artery circulates through the robe and is discharged through the parietal artery at the edge of the robe, and the blood is collected into the choroidal venous vein and discharged out of the eyeball.

Due to this complex structure, details of the etiology and pathology of choroidal blood flow associated with macular degeneration are still poorly known. In particular, choroids are known to receive the most blood flow per unit weight in the human body, and the mechanism of secondary chorioretinal neovascularization due to choroidal ischemia is still unclear.

Therefore, the present invention proposes a blood flow simulation method that can simplify the analysis of choroidal circulation by an electric circuit, and provides a basic framework for future research on choroidal circulation.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to analyze the blood flow volume through the simulation of the choroidal blood flow and to simulate the blood flow volume and blood pressure change of the choroid when abnormal blood vessel abnormality occurs.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention as set forth in the accompanying drawings. It will be possible.

The method for simulating the choroidal blood flow according to the present invention comprises the steps of: generating a capillary blood bed by designating a size of a choroidal capillary bed, a resistance of the inside and outside of the robule, and a robe internal structure; A second step of specifying an artery, wherein the designated artery is numbered in a group; A third step of specifying a vein, wherein the specified vein is numbered in a group; And a fourth step of analyzing the blood flow and indicating the internal and external blood flow and the blood pressure of the robe.

In addition, when the first-stage blood vessel bed is formed, a hexagonal blood vessel bed is generated, and the accurate resistance value can be changed at each point of the generated hexagon. The arterial pressure of the group designated by the same number can be changed so that the vein pressure of the group designated by the same number can be changed. In the fourth step, the blood flow analysis is divided into a darker black as the blood flow is smaller and a bright white as the blood flow is larger, and the flow of the blood flow is indicated by an arrow, .

According to the solution of the above-mentioned problem, the present invention can easily simulate the inner and outer blood flow and blood pressure of the robe by analyzing the choroidal blood flow volume through simulation of the choroidal blood flow.

FIG. 1 is a diagram showing a step of analyzing the blood choroid blood flow simulation of the present invention.

2 is a photograph showing a step of generating a blood vessel bed in a first step (S10) of the present invention.

3 is a photograph showing the blood vessel bed produced in the first step (S10) of the present invention.

Fig. 4 is a schematic diagram showing a choroidal blood vessel as an electric circuit model according to the present invention. Fig.

Fig. 5 is a photograph showing the step of designating the artery in the second step S20 of the present invention.

6 is a photograph showing a step of specifying a vein in a third step S30 of the present invention.

FIG. 7 is an enlarged photograph of a blood vessel bed after the third step (S30) of the present invention is performed.

8 is a photograph showing the step of performing the fourth step (S40) of the present invention.

9 is a photograph showing blood flow analysis as a fourth step (S40) of the present invention.

10 is an enlarged photograph of the fourth step (S40) of the present invention.

The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent by reference to an embodiment which will be described in detail below with reference to the accompanying drawings.

First, FIG. 1 is a diagram showing a step of simulating an ocular blood vessel flow according to the present invention. The method for simulating the choroidal blood flow of the eye, which is performed by a computer or a software on a computer, includes a computer system input unit for inputting the choroidal image data of a patient and generating a blood vessel bed, a blood vessel bed generated by the computer system input unit A computer system control unit for designating an artery and a vein and analyzing the blood flow rate, and a computer system output unit for outputting the blood flow and the blood pressure. The blood flow measurement of the ocular blood vessel is preferably measured by the following steps.

First, the first step S10 creates a blood vessel bed. Specifically, as shown in FIG. 2, it is preferable to designate the size of the blood vessel bed, the inner and outer resistance of the blood vessel, and the inner structure of the robe, thereby generating the blood vessel bed.

The size of the blood vessel bed can be specified by dividing into the lengths (Columns) and the widths (Rows). In addition, the inner and outer resistance of the ocular blood vessel can be designated as 1 to 16 OMEGA. In addition, the robe internal structure can be set as a simple structure, a double structure and a triple structure.

When the blood vessel bed of the first step S10 is generated, a hexagonal blood vessel bed is generated as shown in FIG. 3, and an accurate resistance value is displayed at each point of the generated hexagon. It is preferable that the present invention includes a magnifying glass so that the resistance value displayed at each point of the generated hexagon can be enlarged and displayed.

The choroidal blood vessel of Fig. 4 (a) was designed as a blood vessel bed as shown in Fig. 4 (b). Each line of the vascular bed lattice shown in FIG. 4 (b) has a resistivity of 16? Representing a capillary, and the boundary of the generated hexagons is preferably designed to have a resistance of 1? 16 ?. Also, as shown in Fig. 4 (b), it is desirable to design a double-layered hexagon with an internal grid of triangles to represent blood vessel lobules. It is preferable that the internal structure of the robe can be changed to a one-layer hexagonal shape for a simple shape, a two-layer hexagonal shape for a double shape, and a three-layer hexagonal shape for a triple shape.

In addition, the internal and external resistance of the ocular blood vessel was calculated by assuming that the collecting venous diameter was one to two times the capillary diameter, and the flow resistance was calculated by Poiseuille's equation to the fourth square of the radius of the blood vessel (r ⁴ ) And inversely proportional.

Also, in the design of the vascular bed, an anode supplied to the endarterectomy was placed at the center of the hexagon, and cathodes representing vein discharge were connected to the edge of the hexagon. It was designed based on the results of histological study of choroidal capillary layer.

In the design of the blood vessel bed, the voltage is set to be arbitrarily set by the user, and the arterioles are set to 50V so that the blood vessels in the choroidal arteries of the human eye and the blood pressure (mmHg) Do.

The blood vessel bed is provided so that the user can arbitrarily set the size of the array, and is preferably set to be arranged in a total of 25 or 5 x 5 hexagons as shown in 4 (c).

Next, the second step S20 designates an artery in the blood vessel bed generated in the first step S10. Specifically, as shown in Fig. 5, the designated arteries are numbered in groups.

It is preferable that the artery pressure of the group designated by the same number is changeable by a user, and that the number designation for grouping the designated arteries is changeable by a user.

As shown in FIG. 5, the number inside the red circle represents the arterial group number, and it is preferable that the arterial pressure is displayed at the upper end of the red circle so as to be identifiable by the user.

Next, in a third step S30, a vein is assigned to the blood vessel bed generated in the first step S10. Specifically, as shown in Fig. 6, the specified veins are numbered in groups.

As in the arterial designation in the second step S20, the vein pressure of the group designated by the same number can be changed by the user, and the number designation for grouping the designated vein can be changed by the user desirable.

As shown in FIG. 6, the number inside the blue circle represents the vein group number, and it is preferable that the number is indicated by the user indicating the vein pressure at the top of the blue circle.

Next, in a fourth step (S40), the blood flow is analyzed to show the inner and outer blood flow and blood pressure of the blood vessel.

FIG. 8 is a photograph showing blood flow analysis in the fourth step (S40).

As shown in FIG. 9, the blood flow analysis of the fourth step S40 may be divided into a darker black as the blood flow is smaller, and a brighter white as the blood flow is larger.

Further, as shown in FIG. 9, it is preferable that the flow of the blood flow is indicated by an arrow, and the blood flow amount is divided according to the thickness.

The ocular blood vessel blood flow simulation method according to the present invention was analyzed based on Kirchhoff's current law in which the total of the in-out currents at all points where the currents are merged is always zero. In addition, the channel flow of each blood vessel was calculated by current, and the direction and amount of blood flow were represented by arrow and thickness, respectively. The average current of the hexagon was also analyzed.

According to the solution of the above problem, the present invention can easily simulate the blood flow and internal and external blood flow of the choroidal robule by analyzing the blood flow volume through simulation of the choroidal blood flow.

As described above, it is to be understood that the technical structure of the present invention can be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention.

Therefore, it should be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, All changes or modifications that come within the scope of the equivalent concept are to be construed as being included within the scope of the present invention.

Claims

A method of generating a blood vessel bed by inputting a patient's choroidal image data into a computer system input unit and designating the size of the choroidal vascular bed, the internal and external resistance of the robe, Stage 1;

A second step of assigning an artery to a blood vessel bed generated by the computer system input unit by a computer system control unit, and numbering the designated artery into a group;

A third step of assigning a vein to the artery designated by the computer system control unit by the computer system control unit, and numbering the designated vein into a group;

And a fourth step of analyzing the blood flow volume using the computer system control unit and displaying the internal and external blood flow and the blood pressure of the robe on the computer system output unit.
In the arterial designation of claim 1,

And the arterial pressure of the group designated by the same number can be changed.
In the vein designation of claim 1,

And the venous pressure of the group designated by the same number can be changed.
The method according to claim 1,

In the fourth step,

The smaller the blood flow is, the darker the blood is, and the larger the blood flow is,

Wherein the flow of the blood flow is indicated by an arrow, and the blood flow amount is divided according to a thickness of the blood flow.