KR102735866B1 - Method and Equipment of Measuring Simulated Arterial Blood Flow Velocity using Blood Vessel B-mode Ultrasound Imaging - Google Patents

Abstract

The present invention relates to a method and device for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound images, which can accurately measure blood flow velocity by simulating blood flow under conditions similar to reality, and thereby quantitatively obtain vascular B-mode ultrasound images.
In order to solve the above-mentioned problem, the present invention provides a device for measuring a simulated arterial blood flow velocity using a vascular B-mode ultrasound image, comprising: a blood flow-simulating unit configured to circulate a predetermined amount of simulated blood along a tube simulating an arterial blood vessel; and a blood flow measuring unit configured to measure the velocity of the simulated blood flowing along the blood flow-simulating unit, wherein the blood flow-simulating unit includes: a fluid tank in which a predetermined amount of simulated blood is stored; a water pump configured to pump the simulated blood stored in the fluid tank and circulate it along the tube; and a phantom of a predetermined size that is installed so as to allow the tube to penetrate therethrough and simulates skin made of a flexible material, and wherein the water pump is configured as a quantitative pump.

Description

{Method and Equipment of Measuring Simulated Arterial Blood Flow Velocity using Blood Vessel B-mode Ultrasound Imaging}

The present invention relates to a method and device for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound images, and more particularly, to a method and device for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound images, which acquire blood flow B-mode ultrasound images through a phantom simulating an artery and a quantitative pump device simulating cardiac pumping, and then measure blood flow velocity from predicted blood flow velocity field information by applying an AI deep learning model.

In general, vascular B-mode ultrasound images are images that change the intensity of the reflected ultrasound waves into point brightness and display the image as a density according to the amplitude. This is an imaging technique used in most ultrasound diagnostic equipment, and through these vascular B-mode ultrasound images, the movement of organs is visualized in real time.

Additionally, most ultrasound diagnostic equipment measures blood flow velocity by selecting a location to shoot using B-mode images and then measuring blood flow velocity using color/power Doppler images.

However, Doppler imaging has the disadvantage that the measurement results can vary greatly depending on the skill level of the photographer, and there is also the problem that side effects may occur in the patient if a contrast agent is used.

Therefore, instead of using Doppler images that apply the Doppler principle, there is a need for the invention of a blood flow velocity measurement device that uses pure B-mode images. However, the blood flow signal of the B-mode image obtained through this method is mixed with noise signals, so there is a problem that it is difficult to accurately interpret the blood flow signal using a general image processing method.

In order to solve the above problems, various methods and devices are being developed to simulate blood flow velocity, etc. through devices that simulate the flow of blood flow. An example of this is the coronary artery blood flow simulator disclosed in Patent Publication No. 2106631 (hereinafter referred to as “patent document”).

The above patent document comprises: a simulated blood vessel forming a blood vessel model; a reservoir capable of containing a fluid; a first tube connecting the reservoir and the simulated blood vessel; a second tube connecting the reservoir and the simulated blood vessel; a first pump disposed in the first tube; a first valve disposed in the first tube; a second valve disposed in the second tube; and a third tube connecting the first valve and the second valve, wherein the first pump causes a fluid contained in the reservoir to flow to the first valve, and the fluid flows to the simulated blood vessel and the second valve connected through the third tube by controlling the first valve, and the second valve causes the fluid to flow to the reservoir and the simulated blood vessel, and includes a resistor disposed in the third tube and having an inner diameter of 100 to 200% of the inner diameter of the simulated blood vessel.

However, the above patent document measures the pressure and flow of the stenotic portion of the simulated blood vessel by inserting a wire-type sensor into the simulated blood vessel while allowing the fluid to circulate through the simulated blood vessel. However, in this case, since the degree of stenosis of the simulated blood vessel can be arbitrarily changed from what was initially set by the wire-type sensor, there is a problem in that the accuracy of the measured blood flow information is reduced.

In addition, since blood flow measurement is possible under only one condition at a time, there is the inconvenience of having to individually manufacture a simulated blood vessel section according to the various conditions of the blood vessel that require simulation.

Therefore, there is a need to develop a blood flow velocity measurement method and device with an improved structure that can accurately measure blood flow velocity by simulating blood flow under conditions similar to reality.

KR 10-2106631 B1 (2020. 04. 24.) KR 10-1907672 B1 (2018. 10. 05.) KR 10-2339098 B1 (2021. 12. 09.) KR 10-2023-0106949 A (2023. 07. 14.)

The present invention has been made to solve the problems of the conventional blood flow measurement methods and devices as described above, and the problem that the present invention seeks to solve is to provide a method and device for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound images, which can accurately measure blood flow velocity by simulating blood flow under conditions similar to reality, and thereby quantitatively obtain vascular B-mode ultrasound images.

In order to solve the above-mentioned problem, the present invention provides a device for measuring a simulated arterial blood flow velocity using a vascular B-mode ultrasound image, comprising: a blood flow-simulating unit configured to circulate a predetermined amount of simulated blood along a tube simulating an arterial blood vessel; and a blood flow measuring unit configured to measure the velocity of the simulated blood flowing along the blood flow-simulating unit, wherein the blood flow-simulating unit includes: a fluid tank in which a predetermined amount of simulated blood is stored; a water pump configured to pump the simulated blood stored in the fluid tank and circulate it along the tube; and a phantom of a predetermined size that is installed so as to allow the tube to penetrate therethrough and simulates skin made of a flexible material, and wherein the water pump is configured as a quantitative pump.

Another feature of the blood flow simulating unit of the present invention is that the operation of the water pump is controlled at a constant cycle to simulate the pulsation of blood flow.

In addition, the present invention is characterized in that first and second anti-reflux valves are further installed on the tube located on the upper and downstream sides with respect to the phantom to prevent the reverse flow of simulated blood.

In addition, the present invention is characterized in that a flow meter for examining the blood flow rate of the simulated blood is further installed on the tube passing through the phantom and connected to the fluid tank.

Meanwhile, a method for measuring a simulated arterial blood flow velocity using a vascular B-mode ultrasound image according to the present invention is characterized by including a simulated blood storage step of storing simulated blood in a fluid tank; a tube installation step of installing a plurality of tubes simulating blood vessels to circulate through the fluid tank and a phantom simulating skin tissue; a simulated blood pumping step of pumping the simulated blood stored in the fluid tank through a water pump installed on the plurality of tubes; a blood flow measurement step of measuring the flow of the simulated blood passing through the plurality of tubes and the phantom using ultrasound; a deep learning step of performing machine learning based on the measured blood flow velocity data; and a blood flow velocity prediction step of predicting the blood flow velocity by comparing the blood flow velocity learned through the deep learning step with a blood flow signal in an actually photographed vascular B-mode ultrasound image.

According to the present invention, the blood flow velocity in blood vessels (arteries) located in different parts of the human body can be simulated to suit actual blood flow through a blood flow simulating unit that simulates human blood and blood vessels, and through this, the velocity of the simulated blood flow in the simulated blood vessels can be compared and evaluated using the Doppler function of the blood flow measuring unit, and there is an advantage in that the actual blood flow velocity can be measured only with a vascular B-mode ultrasound image by utilizing the data accumulated in this way.

Figure 1 is a configuration diagram showing an example of a simulated arterial blood flow velocity measurement device using vascular B-mode ultrasound images according to the present invention.
FIG. 2 is a drawing showing an example in which the first and second anti-return valves are installed in the phantom of the blood flow simulating section according to FIG. 1.
FIG. 3 is a schematic diagram showing another embodiment of a simulated arterial blood flow velocity measurement device using vascular B-mode ultrasound images according to the present invention.
FIG. 4 is a drawing showing an example in which the first and second anti-return valves are installed in the phantom of the blood flow simulating unit according to FIG. 3.
Figure 5 is a drawing showing an example of a sealing member being installed in a phantom according to the present invention.
Figure 6 is a drawing showing an example of a sealing member and a sealing cap being installed in a phantom according to the present invention.
Figure 7 is a flow chart showing an example of a method for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound images according to the present invention.

Hereinafter, a detailed description will be given with reference to the attached drawings illustrating preferred embodiments of the present invention.

The present invention provides a method and device for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound images, which can accurately measure blood flow velocity by simulating blood flow under conditions similar to reality, and thereby quantitatively obtain vascular B-mode ultrasound images. The present invention includes a blood flow simulating unit (10) and a blood flow measuring unit (20), as illustrated in FIG. 1.

The blood flow simulation unit (10) is configured to simulate human blood flow, and as illustrated in FIG. 1, the blood flow simulation unit (10) includes a fluid tank (11) in which a predetermined amount of simulated blood is stored, a water pump (12) that pumps the simulated blood stored in the fluid tank (11) and circulates it along the tube; and a phantom (13) of a predetermined size that simulates skin made of a flexible material and is installed so that the tube passes through it.

At this time, a stirrer (not shown) that rotates by a motor or the like may be installed inside the fluid tank (11) to prevent the stored simulated blood from coagulating.

And the simulated blood stored in the fluid tank (11) can be a blood-mimicking fluid (Doppler Fluid) of 'CIRS Inc. (SUN NUCLEAR)' of the United States that can simulate human red blood cells, 'Model 769DF'.

Additionally, the water pump (12) may be configured as a peristaltic pump so that it can be set and quantitatively controlled at a desired speed within a range of 1 to 1000 ml/min.

More preferably, the metering pump may be configured as a tubing pump, and a roller provided inside the header of the tubing pump may be configured to pressurize the tube so that the simulated blood inside the tube is discharged in a certain direction, and the operation of the water pump (12) may be controlled at a certain cycle so that the pulsatile nature of the blood flow is simulated.

At this time, in order to prevent a backflow phenomenon occurring during the time interval in which the ruler of the water pump (12) is released, as illustrated in FIG. 2, first and second backflow prevention valves (V1, V2) for preventing backflow of blood may be installed on the tubes on the upstream side (between the water pump (12) and the phantom (13)) and the downstream side (between the phantom (13) and the fluid tank (11)) of the phantom (13), and these first and second backflow prevention valves (V1, V2) may be installed on the upstream and downstream tubes spaced 5 to 10 cm apart from the phantom (13), and this is to minimize the influence of the configuration of the backflow prevention valves (V1, V2) on the blood flow velocity of the simulated blood passing through the phantom (13).

Although the first and second anti-return valves (V1, V2) are described above, they are not limited to the configuration of a conventional valve, and may be implemented by changing the structure to various types of valves or caps that can block the flow in the reverse direction while minimizing the resistance in the direction in which the simulated blood flows.

And the phantom (13, Flow Phantom) can be composed of a block of silicone material having a predetermined thickness and a predetermined length, and the phantom (13) can be formed with first, second, and third through-holes (H1, H2, H3) in which first, second, and third tubes (T1, T2, T3) having different diameters and simulating blood vessels are selectively installed, as shown in FIG. 2.

At this time, the first through hole (H1) can be formed to have a diameter of 4 mm, the second through hole (H2) can be formed to have a diameter of 6 mm, and the third through hole (H3) can be formed to have a diameter of 8 mm. This is to simultaneously measure blood flow velocity fields under various conditions (such as vascular stenosis).

In addition, the first, second, and third tubes (T1, T2, and T3) simulating arterial blood vessels may be formed as transparent or translucent tubes made of silicone material with an inner diameter of 6 to 6.4 mm and an outer diameter of 9 to 9.6 mm in consideration of actual blood vessels, and these first, second, and third tubes (T1, T2, and T3) may be configured such that the tube sections on both sides are separated and combined based on the phantom (13) so as to enable partial replacement.

In addition, as shown in FIGS. 3 and 4, an ultrasonic flow meter (14) may be installed inside the tube to detect the blood flow velocity inside the tube and verify the speed of the water pump (12) so that the blood flow of the simulated blood flowing inside the tube closely resembles the actual arterial blood flow. Through this ultrasonic flow meter (14), the blood flow velocity inside the tube can be accurately detected using ultrasonic waves from the outside of the tube without affecting the blood flow inside the tube.

At this time, the flow meter (14) can be installed on the tube on the downstream side (between the phantom (13) and the fluid tank (11)) based on the phantom (13), and more preferably, can be installed on the tube within 20 cm based on the phantom (13) and configured to detect whether the blood flow speed of the simulated blood is maintained constant, and based on the blood flow speed detected in this way, the operation of the water pump (12) is optimally controlled to be close to the pulsation of the actual blood flow.

Here, if the flow meter (14) is installed at a position more than 20 cm apart from the phantom (13), the effect of measuring the speed of blood flow changing through the phantom (13) is reduced, so it is not desirable to use it as a criterion for controlling the operation of the water pump (12). Accordingly, in the present invention, the flow meter (14) is installed on a tube within 20 cm apart from the phantom (13).

In addition, when a gap (G) of a predetermined interval is formed between the outer surface of the tube (the first, second, third tube (T1, T2, T3)) installed to penetrate the through-hole (the first, second, third through-hole (H1, H2, H3)) of the phantom (13) and the inner surface of the through-hole, the blood flow velocity may not be accurately measured through the ultrasonic waves of the blood flow measurement unit (20) described later, and to prevent this, an ultrasonic gel (Ultrasound Transmission Gel) may be filled in the gap (G) between the through-hole and the tube.

To this end, a ring-shaped sealing member (S) having a predetermined diameter to penetrate the tube is installed, and one end of the tube is inserted to penetrate the through hole of the phantom (13), and through this, one end of the tube passes through the through hole of the phantom (13) and protrudes to a predetermined length, and then another sealing member (S) is installed on one end of the protruding tube.

Then, a sealing member (S) fitted into the tube is inserted into one side of the through hole of the phantom (13) to cover the gap (G), and a predetermined amount of ultrasonic gel is filled into the gap (G) through the other side of the phantom (13), and then the sealing member (S) fitted into the tube is inserted into the other side of the through hole of the phantom (13) to cover the gap (G), and as a result, as shown in FIG. 5, the sealing members (S) are installed on both sides of the phantom (13) to prevent the ultrasonic gel filled in the gap (G) from leaking to the outside.

In the above, it has been illustrated and described that sealing members (S) are inserted on both sides of the through hole of the phantom (13) to cover the gap (G), but in this case, the inserted sealing members (S) may flow due to the repetitive pulsation of blood flow, causing the ultrasound gel filled in the gap (G) to leak to the outside. Therefore, in order to more reliably and sturdily fix the sealing members (S) to both sides of the phantom (13), a sealing cap (C) of a predetermined size that is tightly fixed to both sides of the phantom (13) may be further installed.

As shown in Fig. 6, this sealing cap (C) is formed in a disc shape with a predetermined diameter, and a hole (no drawing symbol) having a diameter relatively larger than the diameter of the tube is formed in the center portion to be inserted into the tube, and a plurality of fixing protrusions (no drawing symbol) are formed protruding on one side to be forcibly inserted and fixed into the side of the phantom (13) as shown in Fig. 6.

At this time, the sealing cap (C) is formed in a 'C' shape with one side of the hole cut to a predetermined width, and the sealing cap (C) can be configured to be installed by fitting it onto the side of the tube through the cut portion.

The blood flow measurement unit (20) is configured to measure the blood flow velocity field of simulated blood flowing through a phantom (13) using ultrasound.

This blood flow measurement unit (20) may be composed of an ultrasonic beam former (21) that generates an ultrasonic beam as shown in FIGS. 1 and 3, and an ultrasonic probe (22) that measures blood flow velocity using ultrasonic waves generated through the ultrasonic beam former (21).

At this time, the ultrasonic probe (22) can be installed to measure the blood flow velocity inside the tube by ultrasonic waves, which is installed from the outside of the phantom (13) to penetrate the inside of the phantom (13) to minimize the influence on the tube and the phantom (13).

And the raw data (B-mode) measured through the ultrasound probe (22) is subjected to an algorithm for measuring the blood flow velocity field, and then the blood vessel image is reconstructed in high resolution, and the blood vessel velocity field image is repeatedly learned by the artificial intelligence deep learning technique.

To explain this in more detail, when raw data (B-mode) is input, a SVD filter (Singular Value Decomposition Filter) is applied to the raw data to remove noise, and then a blood flow velocity field algorithm is applied to the image from which noise has been removed, and then a deep learning-based super-resolution ultrasound image acquisition algorithm (DL-SRU) is applied.

At this time, the blood flow velocity field algorithm can be applied to the fast multi-object tracking algorithm for motion estimation disclosed in the known academic paper "TracTrac: a fast multi-object tracking algorithm for motion estimation, author Joris Heyman, Computers & Geosciences, Vol. 128, July 2019, pp. 11-18".

And the deep learning-based super-resolution ultrasound image acquisition algorithm (DL-SRU) can be applied with the AI deep learning training technique (algorithm) disclosed in Patent Publication No. 2248444 (Method for generating ultrasound images and devices performing the same).

Meanwhile, the above description only shows and explains that the through holes (first, second, third through holes (H1, H2, H3)) of the phantom (13) are formed to have different diameters, but unlike this, they can be formed to be inclined at a predetermined angle so that the diameter of one end of the through hole is formed to be relatively larger or smaller than the diameter of the other end, and alternatively, they can be formed to be inclined at a predetermined angle so that the diameter of the middle part is formed to be relatively smaller than the diameter of the two ends of the through hole.

In addition, although it is illustrated and described above that only the first, second, and third through-holes (H1, H2, H3) are formed in one phantom (13), it is also possible for one or more through-holes to be formed in one phantom (13).

In addition, the above description only shows and explains that multiple through holes of different diameters are formed in the phantom (13) and tubes are inserted and installed to penetrate the interior. However, unlike this, the phantom (13) may be configured to be mounted on a pressurizing unit (not shown) having a predetermined size and then selectively pressurized to a set pressure through the pressurizing unit.

At this time, the pressurizing unit may be equipped with a pressurizing portion (not shown) corresponding to the size of the phantom (13) so that the entire phantom (13) can be pressurized with the same pressure, and a pressure measuring device (not shown) such as a load cell for measuring the pressure applied to the phantom (13) through the pressurizing portion may be installed in the mounting portion (not shown) on which the phantom (13) is mounted.

In addition, the above is only illustrated and described as the phantom (13) being formed in a block shape having a predetermined size and then having multiple penetration holes formed to penetrate both sides, but it can be implemented by changing it to be formed of a pair of upper and lower phantom parts (not illustrated) having a predetermined size and then having semicircular mounting grooves (not illustrated) formed on surfaces facing each other, and the upper phantom part being attached to the bottom surface of the pressurizing part and the lower phantom part being attached to the top surface of the mounting part.

With this configuration, instead of inserting the tube through the penetration hole, the tube is seated in the mounting groove at a position where the upper and lower phantom sections are spaced apart from each other, and then the pressurizing section is lowered to a predetermined height to pressurize the tube seated in the mounting groove to a predetermined pressure, so that blood flow can be measured under various conditions.

At this time, by changing the diameter of the settling groove, it can be configured so that even if the pressurized portion presses the upper and lower phantom portions with the same pressure, a difference occurs in the pressure applied to the tube.

Hereinafter, a method for measuring blood flow velocity using a simulated arterial blood flow velocity measuring device using vascular B-mode ultrasound images according to the present invention is described.

After a predetermined amount of simulated blood is filled (stored) inside the fluid tank (11) (simulated blood storage step (S10)), one end of a tube, which is a simulated blood vessel, is connected to be immersed in the simulated blood inside the fluid tank (11) to a predetermined depth, and then the other end of the tube is connected to the suction port of the water pump (12).

Then, one end of another tube is connected to the discharge port side of the water pump (12), and the other end of the tube is installed to penetrate the through hole of the phantom (13), and then connected to recover the simulated blood into the interior of the fluid tank (11) (tube installation step (S20)).

When the tube installation is completed as above, the water pump (12) is operated and controlled so that the simulated blood is pumped from inside the fluid tank (11) and passes through the phantom (13) (simulated blood pumping step (S30)).

Thereafter, the blood flow velocity of the simulated blood flowing inside the tube passing through the phantom (13) is measured through the blood flow measurement unit (20), and the data thus measured is stored as raw data (B-mode) (blood flow velocity measurement step (S40)).

Once the raw data is stored as above, an SVD filter, a velocity field algorithm, and a deep learning-based super-resolution ultrasound image acquisition algorithm (DL-SRU) are sequentially applied to the raw data (deep learning step (S50)), and the learned data is used to predict blood flow velocity from raw data (B-mode) actually measured from a patient (blood flow velocity prediction step (S60)).

As described above, the present invention can simulate blood flow velocity in blood vessels (arteries) located in different parts of the human body appropriately to actual blood flow through a blood flow simulation unit that simulates human blood and blood vessels, and through this, the velocity of simulated blood flow in the simulated blood vessels can be compared and evaluated using the Doppler function of the blood flow measurement unit, and by utilizing the data accumulated in this way, the actual blood flow velocity can be measured using only a vascular B-mode ultrasound image.

In the above, for the convenience of explanation, the preferred embodiments have been described with drawings and reference numerals and names assigned to the components shown in the drawings. However, this is only one embodiment according to the present invention, and the scope of the rights should not be interpreted as being limited to the shapes and names assigned in the drawings. It should be readily apparent that changes to various shapes predictable from the description of the invention and simple substitutions with components that perform the same function are within the scope of changes that can be easily performed by those skilled in the art.

10: Blood flow simulation unit 11: Fluid tank
12: Water pump 13: Phantom
14: Flow meter 20: Blood flow measurement unit
20: Blood flow measurement unit 21: Ultrasound beam former
22: Ultrasonic probe C: Sealing cap
G: Gap H1: First through hole
H2: Second through hole H3: Third through hole
S: Sealing member T1: First tube
T2: Second tube T3: Third tube
V1: 1st check valve V2: 2nd check valve

Claims (5)

In a simulated arterial blood flow velocity measuring device,
A blood flow simulating unit (10) configured to circulate a predetermined amount of simulated blood along a tube simulating an arterial blood vessel; and
A blood flow measurement unit (20) that measures the speed of the simulated blood flowing along the blood flow simulation unit (10);
It consists of,
The above blood flow mimicking part (10) is
A fluid tank (11) in which a predetermined amount of simulated blood is stored;
A water pump (12) that pumps the simulated blood stored in the fluid tank (11) and circulates it along the tube; and
A phantom (13) of a predetermined size that simulates skin made of a flexible material and is installed so that the above tube penetrates through it;
Including,
The above water pump (12) is
It consists of a quantitative pump,
On the tube located above and below the phantom (13),
The first and second anti-reflux valves (V1, V2) are installed to prevent the backflow of the simulated blood.
The above phantom (13) is
A device for measuring blood flow velocity in a simulated artery using B-mode ultrasound images of blood vessels, characterized in that a through-hole through which the tube penetrates is formed, an ultrasound gel is filled in a space (G) between the through-hole and the tube, a sealing member (S) is installed in the tube, and the sealing member (S) is inserted into the through-hole on both sides of the phantom (13) so as to cover the space (G) filled with ultrasound gel.
In claim 1,
The above blood flow mimicking part (10) is
A device for measuring the velocity of a simulated arterial blood flow using a B-mode ultrasound image of a blood vessel, characterized in that the operation of the water pump (12) is controlled at a regular cycle to simulate the pulsation of blood flow.
delete In claim 1 or claim 2,
On the tube that passes through the above phantom (13) and is connected to the fluid tank (11),
A simulated arterial blood flow velocity measurement device using vascular B-mode ultrasound images, characterized in that a flow meter (14) for examining the blood flow velocity of simulated blood is further installed.
In a method for measuring blood flow velocity using a simulated arterial blood flow velocity measuring device using a vascular B-mode ultrasound image according to claim 1,
Simulated blood storage step (S10) for storing simulated blood in a fluid tank (11);
A tube installation step (S20) in which a plurality of tubes simulating blood vessels are installed to circulate through the fluid tank (11) and the phantom (13) simulating skin tissue;
A simulated blood pumping step (S30) of pumping simulated blood stored in the fluid tank (11) through a water pump (12) installed on the plurality of tubes;
A blood flow velocity measurement step (S40) for measuring the flow of simulated blood passing through the plurality of tubes and the phantom (13) using ultrasound;
A deep learning step (S50) for performing machine learning based on measured blood flow velocity data; and
A blood flow velocity prediction step (S60) for predicting the blood flow velocity by comparing the blood flow velocity learned through the above deep learning step (S50) with the blood flow signal in an actually captured blood vessel B-mode ultrasound image;
A method for measuring simulated arterial blood flow velocity using vascular B-mode ultrasound imaging, characterized in that it includes.

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