WO2019036897A1

WO2019036897A1 - Multifunctional intravascular ultrasonic imaging device

Info

Publication number: WO2019036897A1
Application number: PCT/CN2017/098444
Authority: WO
Inventors: 邱维宝; 苏敏; 张鹏飞; 张利宁; 郑海荣
Original assignee: 深圳先进技术研究院
Priority date: 2017-08-22
Filing date: 2017-08-22
Publication date: 2019-02-28

Abstract

A multifunctional intravascular ultrasonic imaging device comprises a catheter (2) and an ultrasonic probe (3) located at the front end of the catheter (2). The ultrasonic probe (3) is provided with a housing (31), and comprises one or more front-viewing imaging transducers (41) and one or more slant-viewing imaging transducers (42) all fixed in the housing (31). The front-viewing imaging transducers (41) are used for performing ultrasonic imaging on a vascular atherosclerotic plaque to detect the forms of the plaque. The slant-viewing imaging transducers (42) are used for performing blood flow imaging to detect the speed of a blood flow near the plaque and detect the forms of the plaque at multiple angles. The front-viewing imaging transducers (41) are disposed in a direction parallel to the axial direction of the housing (31), and the slant-viewing imaging transducers (42) are arranged at certain angles with the front-viewing imaging transducers (41), so as to perform tissue imaging and blood flow imaging at different angles. The blood flow information near the imaged tissues can be detected while tissue imaging is performed. The transducers (4) can perform tissue imaging at multiple angles and can multidimensionally perform plaque imaging.

Description

Multifunctional intravascular ultrasound imaging device

Technical field

The present invention generally relates to the field of medical ultrasound imaging, and more particularly to a multifunctional intravascular ultrasound imaging apparatus.

Background technique

Atherosclerosis is a cardiovascular disease with a high mortality rate, and one of the most prominent features is that it is not easily diagnosed before the onset of the disease. The underlying pathological mechanism of more than 75% of acute coronary syndromes is demonstrated as atherosclerotic plaque rupture. Therefore, the detection and characterization of easily ruptured plaques is the most active area in cardiology and biomedical imaging research. One.

A variety of medical imaging techniques are available for diagnosing vascular atherosclerotic lesions. Angiography is the primary means of detecting atherosclerotic plaques today and is used to determine the location and extent of atherosclerotic stenosis. It quickly injects the contrast agent into the blood vessel under X-ray illumination, because the contrast agent absorbs X-rays and can be developed. From the results of the visualization, blood flow containing the contrast agent can be seen to understand the physiological and anatomical changes of the blood vessel. Angiography is a valuable method for diagnosing vascular-related diseases, but it can only provide lumen contours filled with contrast media, but not the nature and extent of lesions in the wall, most of the vulnerable lesions in the blood vessels. The block was not detected by angiography.

Medical ultrasound imaging technology has become an irreplaceable diagnostic technology in modern medical imaging because of its non-invasive, non-radiative, good real-time, high discriminating power, easy to use, and low price. It has become a clinical diagnosis of various diseases. The preferred method.

Intravascular ultrasound (IVUS) imaging technology is a special imaging technique specifically used in medical ultrasound imaging for cardiovascular disease detection. This technique uses a miniature ultrasound probe (or probe) mounted on the tip of the catheter to insert a two-dimensional tissue image into the suspected lesion in the human blood vessel. It can not only display the shape of the inner wall of the blood vessel in real time, but also measure the size of the lesion through tissue plane analysis and three-dimensional reconstruction, providing a new perspective for understanding the morphology and function of vascular lesions, and providing more for clinical diagnosis and treatment. Accurate and reliable information. Blood vessel In addition to the luminal morphology and vessel wall information, the intra-ultrasound imaging technique can also initially determine the histomorphological features of atherosclerotic plaques. At the same time, the blood vessel diameter, cross-sectional area and stenosis can be measured by accurate quantitative analysis. It can identify early atherosclerotic lesions that cannot be found by angiography, especially for angiographically displayed critical lesions. Intravascular ultrasound imaging can accurately quantify it to determine its stenosis and lesion type to assist clinical treatment. The choice of the program. Intravascular ultrasound imaging technology also has very important application value in guiding coronary interventional therapy. Because the technology can accurately reflect the internal morphology of the blood vessels, the nature and severity of the lesions, so as to provide a basis for selecting the correct treatment strategy, such as selecting a suitable size of the stent. At the same time, intravascular ultrasound imaging can be used to evaluate the effect of postoperative stent treatment, such as whether the stent is fully expanded, whether it is completely attached, whether it is evenly spread and completely covers the lesion, etc., which is conducive to timely finding and correcting the existence of the stent after implantation. Some problems to achieve the best interventional effect.

Intravascular ultrasound imaging is a combination of non-invasive ultrasound technology and invasive catheter technology. Medical imaging technology using a special catheter with an ultrasonic probe attached to the end, showing the wall and plaque of the lesion. Block to improve the accuracy of the diagnosis. Intravascular ultrasound transducers used today are mainly high frequency planar single-element intravascular ultrasound transducers and high frequency annular array intravascular ultrasound transducers.

Intravascular ultrasound imaging techniques that have been proposed in the field include:

Doppler wire: The ultrasonic transducer is mounted on the tip of an intravascular catheter to monitor the flow rate of blood flow. The blood flow information in the blood vessel can be obtained by the Doppler guide wire method. However, since the ultrasonic transducer is installed at the tip end of the guide wire, only the blood flow map can be obtained, and the tissue information of the wall cannot be obtained.

Decorrelation method: blood flow information is obtained by data processing after obtaining data based on conventional intravascular imaging. By analyzing the lateral ultrasonic echo data, the blood flow change region is obtained by the decorrelation method. Since the position of the ultrasonic catheter is not changed, the tissue signal in the echo is relatively unchanged, and the blood flow changes with time, so A blood flow imaging region can be obtained by analyzing the decorrelation of the ultrasound echo data.

The Chinese invention patent filed on February 11, 2015, with the application number CN104349714A, provides an intravascular ultrasound focusing method, a focus diagnostic apparatus, and a focusing transducer. The intravascular ultrasound focusing method includes sending an intravascular ultrasound focused diagnostic instrument to the distal end of the lesion; 360 into the blood vessel The ultrasonic signal is transmitted. The intravascular ultrasound focus diagnostic apparatus includes an ultrasound catheter, a retire/drive device and an electronic imaging system, the front end of the ultrasound catheter is equipped with an intravascular ultrasound focus transducer; the back end is connected to the retrace/drive device; the retrace/drive device Connected to an electronic imaging system. The intravascular ultrasound focusing transducer comprises an ultrasound transducer unit for transmitting an ultrasound signal and receiving the reflected ultrasound signal, and a focusing unit for transmitting the ultrasound signal to the ultrasound transducer unit Focus on. Through intravascular ultrasound focusing technology, the resolution of the diagnostic instrument is improved, and the signal-to-noise ratio of the imaging device is improved, thereby improving the diagnostic accuracy. However, this patent only proposes a general-purpose ultrasound imaging method for intravascular ultrasound, and there is no concept of related intravascular blood flow imaging.

A Chinese invention patent filed on December 2, 2015, with the application number CN105105791A, provides a plurality of transducer delivery devices and methods. A more complete characterization is allowed by measuring the pressure drop across the stenotic lesion and the size of the vascular lumen in the vicinity of the stenotic lesion by using a sensor that is delivered to the stenotic lesion in the blood vessel. In a preferred embodiment, the size (e.g., inner diameter, cross-sectional profile) of the vascular lumen in the vicinity of the stenotic lesion site can be measured by one or more intravascular ultrasound transducers. In a preferred embodiment, the intravascular ultrasound transducer is capable of delivering the pressure transducer to the location of the stenotic lesion site via the same delivery device. Pathological conditions were characterized by intravascular ultrasound imaging and intravascular pressure drop. There are many factors affecting the blood pressure of the human body, and the representation by pressure drop is not necessarily accurate and comprehensive.

In view of this, there is a need for a new multifunctional intravascular ultrasound imaging device.

Summary of the invention

In view of the above deficiencies of the prior art, the present invention provides a bimodal intravascular ultrasound imaging apparatus capable of multi-angle ultrasound imaging and intravascular multi-angle blood flow Doppler imaging of a blood vessel wall, capable of detecting blood vessels at multiple angles. The hardened plaque and the detection of blood flow near the lesion site help doctors get more comprehensive information for a more accurate diagnosis.

The present invention provides a multifunctional intravascular ultrasound imaging apparatus comprising a catheter and an ultrasound probe at a front end of the catheter, the ultrasound probe having a housing, and one or more front view imaging transducers and one fixed in the housing a squint imaging transducer for ultrasound imaging of vascular atherosclerotic plaques for detecting plaque morphology; said squint imaging transducer for performing blood flow imaging to detect plaque formation Blood flow velocity and multi-angle detection The shape of the plaque.

The front view imaging transducer is disposed to be placed parallel to an axial direction of the housing, the squint imaging transducer being arranged at an angle to the front view imaging transducer for tissue imaging at different angles Blood flow imaging.

Preferably, the two or more transducers are arranged side by side within the probe housing or arranged back to back within the probe housing.

Preferably, the transducer is a single-element planar transducer, a single-element focusing transducer, a multi-element planar transducer or a multi-element focusing transducer.

Preferably, the wafer of the transducer comprises a matching layer, a piezoelectric layer and a backing layer, the number of the matching layers being one or more layers.

Preferably, the transducer has a center frequency ranging from 10 MHz to 100 MHz.

Preferably, the position of the transducer can be replaced with other locations located in the outer casing.

Preferably, the probe housing has one or more openings through which the transducer transmits and receives ultrasonic waves.

Preferably, the probe housing has a hollow cylindrical structure with a diameter of 0.4 mm to 2 mm.

Preferably, the multifunctional intravascular ultrasound imaging apparatus further includes a connector having one end connected to the catheter and the other end connected to the imaging system and the withdrawal device for signal transmission and ultrasonic probe retraction.

Preferably, the transducers are arranged to be arranged in such a manner that one of the front view imaging transducers is disposed in the middle with two squint imaging transducers disposed on both sides thereof, the two squint imaging transducers They are respectively arranged at an angle to the front view imaging transducer, and the angle is 0 to 90 degrees.

Preferably, the angle is 30 to 60 degrees.

Advantageous Effects of Invention The multi-function intravascular ultrasound imaging apparatus of the present invention can detect blood flow information in the vicinity of an imaged tissue while imaging the tissue. More than one squint imaging transducer can perform tissue imaging at multiple angles simultaneously, allowing plaque imaging in multiple dimensions.

DRAWINGS

1 is a schematic view showing the structure of an intravascular ultrasound imaging apparatus of the present invention.

2 is a schematic view showing the structure of an ultrasonic imaging probe in the multifunctional intravascular ultrasound imaging apparatus of the present invention.

3 is a schematic view showing the operation of an ultrasonic imaging probe in the multi-function intravascular ultrasound imaging apparatus of the present invention.

Figure 4 is a schematic diagram of pulse excitation.

Figure 5 is a schematic diagram of Doppler imaging.

Detailed ways

Specific embodiments of the present invention will be described below with reference to the accompanying drawings. In the specific embodiments of the invention described below, some very specific technical features are described in order to provide a better understanding of the invention, but it will be apparent to those skilled in the art that not all of these The technical features are all necessary technical features for implementing the present invention. The specific embodiments of the invention described below are merely exemplary embodiments of the invention and are not to be construed as limiting. In addition, some well-known techniques have not been described in order to avoid obscuring the invention.

1 is a schematic view showing the structure of an intravascular ultrasound imaging apparatus of the present invention. As shown in FIG. 1, the intravascular ultrasound imaging apparatus of the present invention comprises a connector 1, a catheter 2 and an ultrasound probe 3. The connector 1 has one end connected to the catheter 2 and the other end connected to an imaging system and a withdrawal device (not shown) for signal transmission and ultrasound probe retraction. The connector 1 has a water injection port 11. The catheter 2 has a protective tube, a metal hose and a transducer cable (coaxial cable) in order from the outside to the inside, and also has a function of transmitting signals and retracting the probe, and the catheter 2 also has a device such as a guide wire and a positioning ring ( Not shown), the position of the transducer can be located and the transducer can be guided to move within the blood vessel. The ultrasound probe 3 is located at the front end of the catheter 2 (i.e., the end remote from the connector 1) for ultrasound imaging.

2 is a schematic structural view of an ultrasonic imaging probe in the multi-function intravascular ultrasound imaging apparatus of the present invention. As shown in FIG. 2, the ultrasonic probe 3 has a housing 31, and a transducer 4 fixed in the housing 31. The outer casing 31 is an outer casing of copper or other metallic material. Transducer 4 (transducer crystal The sheet is fixed in the outer casing 31 using biocompatible glue. In the present embodiment, the transducer 4 includes a front view imaging transducer 41 and two squint imaging transducers 42. The front view imaging transducer 41 is configured to ultrasonically image a vascular atherosclerotic plaque to detect the morphology of the plaque; the squint imaging transducer 42 is configured to perform blood flow imaging to detect blood flow near the plaque Speed and multi-angle detection of plaque morphology. Here, the front view imaging transducer 41 and the squint imaging transducer 42 take different names due to different placement positions, and both may be imaging transducers of the same structure, achieving the same function, both transmitting and receiving ultrasound for ultrasound. Imaging. However, the transducer and the electronic system cooperate to image tissue and blood separately or to simultaneously image tissue and blood by different algorithms. That is, the front view imaging transducer 41 images only the tissue, while the squint imaging transducer 42 simultaneously images tissue and blood. As shown in Fig. 2, the three transducers are arranged to be arranged in such a manner that one of the intermediate frontal imaging transducers 41 is axially parallel to the outer casing of the ultrasonic imaging probe 3, and two squint imaging transducers on both sides 42 is arranged at an angle to the front view imaging transducer 41, respectively. The angle may be from 0 to 90 degrees, preferably from 30 to 60 degrees. The angle may be that the two imaging transducers are at an angle in the same plane, or may be at an angle in different planes. Through the above arrangement, the three transducers can perform ultrasonic transmission and reception at three different angles for tissue imaging and blood flow imaging at different angles. In other embodiments, the number of transducers can be varied. The transducer 4 can include one or more front view imaging transducers 41 and one or more squint imaging transducers 42. The arrangement angle between the squint imaging transducer and the front view imaging transducer can also be appropriately adjusted according to actual needs.

In this embodiment, three transducers are arranged side by side in the ultrasonic probe housing 31, i.e., the orientation of each transducer is the same. In other embodiments, the transducers may also be arranged back to back within the probe housing 31, i.e., the orientation of each transducer is reversed.

In the present invention, the transducer 4 can be a single-element planar transducer, a single-element focusing transducer, a multi-element planar transducer or a multi-element focusing transducer. The wafer of the transducer 4 includes a matching layer 4a, a piezoelectric layer 4b, and a backing layer 4c, wherein the number of matching layers 4a is one or more. The positive pole of the transducer 4 can be connected through the backing layer 4c to the positive pole of the coaxial cable 21 in the conduit 2, and the negative pole of the transducer 4 can be directly connected from the matching layer 4a to the negative pole of the coaxial cable 21, or can be plated. A conductive layer connects the matching layer 4a of the transducer 4 to the outer casing 31, and is connected to the negative pole of the coaxial cable 21 by the outer casing 31. Preferably, the center frequency of the transducer 4 ranges from 10 MHz to 100 MHz. The center frequencies of the front view imaging transducer 41 and the squint imaging transducer 42 may be different. In other embodiments, oblique The view imaging transducer 42 may not require a backing layer 4c in construction. The backing layer has a certain influence on the performance of the transducer, which can increase the bandwidth of the transducer and reduce the sensitivity of the transducer. Since the bandwidth requirement of the squint transducer is not high in the present invention, the squint transducer does not have the backing layer to achieve the object of the present invention and achieve the effects of the present invention.

In the present embodiment, the transducer 4 is located inside the ultrasonic probe housing 31, and preferably may be disposed closer to the center of the shaft of the housing. In other embodiments, the position of the transducer 4 can be replaced with other locations located in the ultrasound probe housing 31 as long as the catheter can be rotated (the catheter will rotate continuously during intravascular ultrasound operation). For example, the transducer 4 may be disposed at the front end of the outer casing 31 or may be disposed at the side of the outer casing 31.

As shown in FIG. 2, the probe housing 31 has an opening 32 through which the transducer 4 transmits and receives ultrasonic waves. In other embodiments, the probe housing 31 can have more than one opening. For example, in the case where the transducers 4 are arranged in a back-to-back manner, the probe housing 31 may have two openings, so that each transducer can perform ultrasonic transmission and reception through corresponding openings, thereby achieving ultrasonic imaging.

In the present embodiment, the probe housing 31 has a hollow cylindrical structure with a diameter of 0.4 mm to 2 mm. The probe housing 31 can also be of other shapes.

Figure 3 is a schematic view of the operation of the multifunctional intravascular ultrasound probe. Among them, the transducer 41 is a front view imaging transducer, and the main function is to perform ultrasonic imaging on the plaque to detect the shape of the plaque, that is, to perform only tissue imaging. The squint imaging transducer 42 on either side of the transducer 41 performs the functions of: a) performing tissue imaging at different angles; b) performing blood flow imaging to detect the velocity of blood flow near the plaque. Transducer 42 has two functions, either for blood flow imaging or for tissue imaging.

Figure 4 is a schematic diagram of pulse excitation. When the transducer is detected, more than two echo signals are received. The existing ultrasound imaging software can be used to establish a functional model to remove uncorrelated signals, leaving relevant signals to analyze blood flow velocity, and through existing Tissue imaging software to analyze tissue imaging. As shown in Fig. 4, the horizontal axis represents time and the vertical axis represents amplitude, and the three waveform diagrams in the figure represent initial signals, blood flow reflection and tissue reflection, respectively. The blood flow velocity can be obtained by reflecting the waveform of the blood flow. The size of the plaque can be obtained by organizing the reflected waveform.

Figure 5 is a schematic diagram of Doppler imaging. As shown in Figure 5, when the object moves away from and close to the probe, the sound source received by the probe changes its frequency, and the object can be calculated by this change. The speed of movement. Medically, ultrasound probes are commonly used for Doppler imaging to detect the velocity of blood flow. 5(a) is a schematic diagram showing the frequency of the receiving sound source when the object is stationary, FIG. 5(b) is a schematic diagram showing the frequency of the receiving sound source when the object moves away from the probe, and FIG. 5(c) is the moving object when the object moves close to the probe. Receive sound source frequency diagram.

The intravascular ultrasound imaging apparatus of the present invention can detect blood flow information in the vicinity of an imaged tissue while imaging the tissue. The oblique-angle imaging transducer tilted at a certain angle can perform tissue imaging at multiple angles at the same time, and can perform plaque imaging in multiple dimensions. Multiple transducers can mutually demonstrate imaging results, making the results more accurate. In addition, blood flow detection is not affected by existing guidewires. The guide wire will pass through the tip of the catheter. The existing squint imaging transducer is mounted on the tip of the catheter and is blocked by the guide wire. The imaging is affected by the guide wire, and the present invention is tilted at an angle due to the squint imaging transducer. , no longer at the tip of the catheter, so blood flow detection is not affected by the existing guide wire.

While the present invention has been described in terms of the preferred embodiments, modifications, substitutions, and various alternatives are possible within the scope of the invention. It should also be noted that there are many alternative ways of implementing the methods and systems of the present invention. Accordingly, it is intended that the appended claims be interpreted as

Claims

A multifunctional intravascular ultrasound imaging apparatus includes a catheter and an ultrasound probe at a front end of the catheter, wherein

The ultrasound probe has a housing, and one or more front view imaging transducers and one or more squint imaging transducers secured within the housing for use in vascular atherosclerotic plaque Ultrasound imaging to detect the morphology of the plaque; the squint imaging transducer is used to perform blood flow imaging to detect the velocity of blood flow near the plaque and to detect the morphology of the plaque at multiple angles.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein said front view imaging transducer is disposed to be placed parallel to an axial direction of said outer casing, said squint imaging transducer being disposed to The front view imaging transducers are arranged at an angle to perform tissue imaging and blood flow imaging at different angles.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein said two or more transducers are arranged side by side in said probe housing or arranged back to back within said probe housing.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein said transducer is a single-element planar transducer, a single-element focusing transducer, a multi-element planar transducer or more The array element focuses on the transducer.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein the transducer wafer comprises a matching layer, a piezoelectric layer and a backing layer, and the number of the matching layers is one or more.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein the transducer has a center frequency ranging from 10 MHz to 100 MHz.
The multifunctional intravascular ultrasound imaging apparatus according to claim 6, wherein the position of the transducer is replaceable at other positions of the outer casing.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein said probe housing has one or more openings through which said transducer performs ultrasonic transmission and reception.
The multifunctional intravascular ultrasound imaging apparatus according to claim 8, wherein said probe housing has a hollow cylindrical structure and has a diameter of 0.4 mm to 2 mm.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, wherein said transducers are arranged to be arranged in such a manner that one of said front view imaging transducers is disposed in the middle, and two sides are disposed on both sides. A squint imaging transducer, the two squint imaging transducers being respectively arranged at an angle to the front view imaging transducer, the angle being 0 to 90 degrees.
The multifunctional intravascular ultrasound imaging apparatus according to claim 10, wherein said preferred angle is 30 to 60 degrees.
The multifunctional intravascular ultrasound imaging apparatus according to claim 1, further comprising a connector, one end of said connector being connected to said catheter, and the other end being connected to an imaging system and a retracting device for signal transmission And the ultrasound probe is retraced.