KR20220030414A - Ultrasonic phantom device for performance evaluation of rotary ultrasonic probe - Google Patents

Abstract

The present invention relates to a multipurpose ultrasonic phantom device for evaluating a rotary ultrasonic probe, which can evaluate performance according to a tissue simulation environment. According to the present invention, the present invention can analyze the performance of the ultrasonic probe by directly comparing an ultrasonic image in a completely underwater environment with the ultrasonic image in the tissue simulation environment. In this regard, the present invention can evaluate a quantitative signal degradation level by comparing the maximum performance of the rotary ultrasonic probe in the underwater environment with a reduced signal in the tissue simulation environment, so that the performance of the complex ultrasonic probe can be evaluated.

Description

Multipurpose ultrasonic phantom device for performance evaluation of rotary ultrasonic probe

The present invention relates to a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer, and more particularly, to a multi-purpose ultrasonic phantom device for performance evaluation of a rotary ultrasonic transducer capable of evaluating the performance depending on whether or not a tissue-simulating environment is present.

In general, an ultrasonic probe or transducer and an ultrasonic sensor use ultrasonic waves to detect defects inside or on the surface without damaging metal or non-metal objects, i.e., materials, parts, structures, and the human body. It is a key component of non-destructive testing technology that evaluates and diagnoses.

Ultrasonic transducers are classified by types of ultrasonic waves such as longitudinal, transverse, and surface waves, and are classified by frequency bands such as high frequency, low frequency, broadband, and narrowband. In addition, it is classified by the contact method or contact such as direct contact type, local contact type, underwater type, and non-contact type. The types are classified according to the curvature of the object. In the ultrasonic probe method using such an ultrasonic probe, the inspector oscillates ultrasonic waves on the inspection object while the ultrasonic probe connected to the inspection equipment is in contact with the inspection object to perform the inspection. In this case, the inspector must apply pressure to the inspection object so that the ultrasonic transducer has a constant contact force to maintain a constant amplitude of the ultrasonic signal oscillated to the inspection object.

Conventionally, according to US Pat. No. 8,480,407, a phantom for short-distance therapy for prostate cancer includes an actual prostate tissue phantom in the shape of a prostate, a perineal tissue phantom surrounding it, and a skin tissue phantom that separates the perineal tissue phantom from the external environment and an enclosure. We provide a phantom that mimics the imaging and mechanical properties of the prostate and surrounding tissues by varying the amount of acoustic scattering particles to differentiate between the prostate tissue phantom and the perineal tissue pattern and periphery. According to this prior art, there is a problem in that it is impossible to compare the maximum performance of the transducer and the performance occurring in the tissue simulation environment in which the signal is attenuated because only the signal of the transducer in the tissue simulation environment is analyzed.

In addition, Korean Patent Application Laid-Open No. 2008-0052135 includes a phantom device capable of measuring the amount of fat in an organ of interest as a shadow distribution of an image using an ultrasound image and evaluating the accuracy of an ultrasound imaging device required for measurement. This is achieved by using a phantom containing a strong ultrasound echo characteristic material and a weak ultrasound echo characteristic material in a specific composition and ratio, which shows a distinct shading distribution during ultrasound imaging. By re-adjusting the imaging characteristics of the ultrasound imaging equipment compared with the shade distribution configuration and ratio, it is possible to obtain a normalized fat mass measurement value of the organ of interest in which the influence of the ultrasound imaging conditions and imaging technique is overcome. However, according to this technology, the accuracy of ultrasound imaging equipment can be evaluated, but performance evaluation such as spatial resolution and penetration depth of ultrasound signals is not considered, and the analysis and resolution of quantitative signal sizes according to the transducer use environment are not considered. There is a problem that high-precision analysis of the data is not possible.

The present invention has been devised to solve the above-described problem, and an object of the present invention is to provide a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer capable of evaluating the performance depending on whether or not a tissue-simulating environment is present.

The present invention is a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer, an ultrasonic transducer, a first phantom for evaluating the ultrasonic image of the ultrasonic transducer by connecting an ultrasonic transducer and a hydrophone in an underwater environment from the outside, and fixing the ultrasonic transducer The second phantom in which the contrast target of the ultrasound image is arranged at a predetermined interval and the ultrasonic signal penetration depth of the axial and lateral resolution of the rotary ultrasonic transducer are evaluated, and the imaging performance by the first phantom and the second phantom In one aspect, it includes an analysis unit for comparing image performance.

On the other hand, in the performance evaluation method using a multi-purpose ultrasonic phantom including an ultrasonic transducer, a first phantom, a second phantom, and an analysis unit, the ultrasound in a state in which the analysis unit is externally connected to a hydrophone in an underwater environment to the first phantom A first evaluation step of evaluating the ultrasound image of the transducer; The analysis unit fixes the ultrasound transducer to the second phantom, and the contrast target of the ultrasound image is arranged at a predetermined interval, and the low acoustic column of the second phantom and the contrast target of the ultrasound image are spaced at a predetermined interval. a second evaluation step of evaluating acoustic image performance; and an analysis step in which the analysis unit compares and analyzes the image performance by the first phantom and the image performance by the second phantom.

According to the present invention, the performance of the ultrasonic transducer can be analyzed in various ways by directly comparing the ultrasound image in a completely underwater environment and the ultrasound image in a tissue simulation environment. In this regard, it is possible to evaluate the quantitative signal degradation level by comparing the maximum performance of the rotary ultrasonic transducer in the underwater environment and the attenuated signal in the tissue-simulating environment, thereby enabling the performance evaluation of the complex ultrasonic transducer.

1 is a view showing the configuration of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention.
2 is a plan view illustrating a phantom for underwater measurement of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention.
3 is a perspective view illustrating a phantom for underwater measurement of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention.
4 and 5 are a plan view and a projection view showing a tissue-simulating phantom of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention.
6 is a flowchart illustrating a performance evaluation method using a multi-purpose ultrasonic phantom according to an embodiment of the present invention.
7 is a view for explaining sound wave characteristics according to an embodiment of the present invention.
8 is a diagram illustrating a linear B-mode image.
9 is a view for explaining a rotational ultrasound image according to an embodiment of the present invention.

Specific structural or functional descriptions presented in the embodiments of the present invention are only exemplified for the purpose of describing embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention may be implemented in various forms. In addition, it should not be construed as being limited to the embodiments described herein, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Meanwhile, in the present invention, terms such as first and/or second may be used to describe various components, but the components are not limited to the terms. The above terms are used only for the purpose of distinguishing one component from other components, for example, within the scope without departing from the scope of the rights according to the concept of the present invention, the first component may be named as the second component, Similarly, the second component may also be referred to as the first component.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In describing the embodiment of the present invention, if it is determined that the description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the description thereof is omitted.

First, the multi-purpose ultrasonic phantom for performance evaluation of the rotary ultrasonic transducer according to an embodiment of the present invention evaluates the axial and lateral resolution and the ultrasonic signal penetration depth of the rotary ultrasonic transducer, and evaluates the performance according to the tissue-simulating environment. An aspect of the ultrasonic transducer performance evaluation that can be done is the phantom.

1 is a view showing the configuration of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention. As shown in FIG. 1 , it includes an ultrasonic probe 100 , a phantom for underwater measurement 200 , a tissue simulating phantom 300 , and an analysis unit 400 .

The ultrasonic transducer 100 according to an embodiment of the present invention may be a rotary ultrasonic transducer. The rotary ultrasonic transducer of the present invention may have a diameter similar to that of a general ultrasonic endoscope for medical images. Alternatively, a transducer smaller than a general ultrasound endoscope may be used because it may enter the first phantom or the second phantom according to the present embodiment. In addition, the ultrasonic transducer of the present invention may have an anterior view like a general endoscope, or may be designed to obtain a lateral rotational image. For example, the rotary ultrasonic transducer is in the form of a capsule, it is possible to rotate based on the axial direction (capsule length direction) and / or lateral direction (direction penetrating vertically through the center of the capsule).

Ultrasound imaging according to an embodiment of the present invention is based on identifying a distance and physical properties based on time and intensity information of a signal, and generating the image as an image.

To explain the distance calculation, the ultrasonic wave generated from the ultrasonic transducer goes straight forward, and when the straight ultrasonic wave collides with an external material and is reflected, the reversed ultrasonic wave reaches the ultrasonic transducer, and the transducer measures the ultrasonic signal as an electrical signal. can Through this series of processes, the ultrasonic transducer receives the ultrasonic signal reflected from the object in the linear direction, and the time interval from when the ultrasonic wave is irradiated to the ultrasonic signal returns can be known, and the ), the distance from the ultrasonic probe to the object can be calculated by calculating time as a distance.

As for the physical properties, the ultrasonic signal (in the form of vibrating as a wave in a sound wave) obtained from an object at a certain distance has a larger amplitude as more ultrasonic waves are reflected, and a smaller amplitude as less ultrasonic waves are reflected. At this time, just as the speed of light is different in media with different refractive indices in 'Snell's Law' in the optical field, and the reflectance of light at the boundary of the media changes, the ultrasonic signal also depends on the value of 'acoustic impedance', which is the intrinsic value of the medium. The degree of reflection and refraction varies. In conclusion, materials can be classified to some extent by the intensity of ultrasonic waves. In general, since equipment manufactured for ultrasound medical imaging is manufactured by matching acoustic impedance to pure water (since most of the body is composed of water), noise is generated to a minimum (represented in black in the image). In the case of air, a strong (almost most) reflection occurs due to the difference in acoustic impedance between water and air, and the image appears excessively bright, and the rear part becomes invisible.

The phantom 200 for underwater measurement according to an embodiment of the present invention is a first phantom, for connecting a hydrophone in an underwater environment to the outside and evaluating the ultrasound image of the ultrasonic probe. The phantom 200 for underwater measurement has an acoustic reflection plate 210 that draws an arc having the same center as a rotary ultrasonic transducer, and a wide empty space 220 without an outer wall so that the hydrophone can be connected from the outside. In this specification, for convenience of explanation, it is described that the medium of the first phantom is pure water, but other mediums having low acoustic impedance may be used.

In the phantom for underwater measurement according to an embodiment of the present invention, the acoustic reflector 210 may be a structure that maximally reflects an ultrasonic signal in order to measure the maximum performance of the ultrasonic module. In the pulse-echo performance evaluation method, which measures the performance of an ultrasonic transducer by maximizing ultrasonic reflection, it is possible to measure the size of an ultrasonic signal in a module in the form of a generally flat reflector. In this embodiment, the maximum performance can be evaluated in the pulse-echo performance evaluation regardless of the rotation angle of the rotary ultrasonic transducer through the circular reflector. The evaluation of maximum performance can generally be carried out in a medium having a low acoustic impedance, such as water.

Referring to FIG. 2 , there is a wire target on the left side, so that resolution of an ultrasound signal and an image of the wire target can be evaluated in an environment with only water. This can be directly compared with the image obtained from the wire target on the left side of the second phantom of FIG. 4 . In the empty space in the lower right of FIG. 2 , if necessary, equipment for measuring a beam pattern (a hydrophone) may be put to make it possible to see the ultrasonic beam forming pattern of the ultrasonic probe. The ultrasonic beam pattern may check the intensity of ultrasonic waves at each location in space and express this as a heatmap image of each cross-section. Such an ultrasound beam pattern can be confirmed in the first phantom including the low acoustic impedance medium.

The tissue-simulating phantom 300 according to an embodiment of the present invention is a second phantom, and is an ultrasonic phantom simulating living tissue. The tissue-simulating phantom 300 includes a low acoustic column 310 containing a low acoustic impedance medium and a plurality of control targets 320 disposed at predetermined intervals.

Similar to the wire target of the first phantom described above, a wire phantom is provided on the left side of the second phantom at the same position as the wire target of the first phantom. Unlike the first phantom in a complete aquatic environment, the second phantom is a living tissue. It may have a simulated medium environment. Through such a design, it is possible to directly compare the effect of the difference between the two environments on the ultrasound image.

According to an embodiment of the present invention, the low acoustic pillar 310 and the control target 320 may be provided in a tissue simulation environment such as the second phantom. The low acoustic column 310 is a space that is not filled with the phantom medium among the tissue-simulating phantoms, and may be, for example, a space such as a column filled with only water. When only water is included, the ultrasound image may generally appear very dark. This is a structure provided to simulate a part filled with water in the body, and various distances and angles can be arranged to compare how accurately images are imaged according to distance.

According to an embodiment of the present invention, the contrast target 320 includes a relatively bright portion (eg, a portion having a medium having a large ultrasonic signal reflection) and a dark portion (eg, a portion having a medium having a low ultrasonic signal reflection). In order to check how well they are distinguished in the actual image and whether the boundary or location is well revealed, medium and small medium with high ultrasonic signal reflection can be arranged according to various distances/positions.

The analysis unit 400 according to an embodiment of the present invention may perform a function of evaluating the penetration depth of ultrasonic signals of axial and lateral resolution of the rotary ultrasonic transducer, and evaluating performance according to whether or not a tissue simulating environment exists. The analysis unit 400 for performing such a function may include a pulse-echo performance evaluation module 410 , a beam pattern measurement module 420 , and a comparison analysis module 430 .

The pulse-echo performance evaluation module 410 of the present invention may perform pulse-echo performance evaluation of the rotary ultrasonic transducer 100 with respect to the acoustic reflection plate 210 of the phantom for underwater measurement.

According to an embodiment of the present invention, the pulse-echo performance evaluation is based on a point having a maximum amplitude in a frequency band and a maximum amplitude amplitude (sensitivity) and bandwidth for an ultrasonic signal in the first phantom, a phantom for underwater measurement. As a result, the width of the section that becomes -6dB and its percentage) can be evaluated.

The beam pattern measuring module 420 of the present invention measures the ultrasonic beam pattern of the rotary ultrasonic probe with respect to an arbitrary target fixed to the phantom for underwater measurement, and evaluates the ultrasonic signal penetration depth of the axial and lateral resolution of the rotary ultrasonic probe The first beam pattern measuring module 421 to measure the ultrasonic beam pattern of the rotary ultrasonic probe with respect to an arbitrary target fixed to the tissue simulation phantom to evaluate the ultrasonic signal penetration depth of the axial and lateral resolution of the rotary ultrasonic probe It may include a second beam pattern measuring module 422 .

According to an embodiment of the present invention, the beam pattern measurement is performed by acquiring an ultrasonic signal from the first phantom, a phantom for underwater measurement, and calculating it as a sound pressure. It can be obtained by measuring ultrasonic intensity and sound pressure in

The comparative analysis module 430 of the present invention evaluates the low acoustic image performance and the contrast performance by placing the low acoustic column and the contrast target of the ultrasound image at a predetermined interval in the tissue simulation phantom. This comparative analysis module may be performed by comparing images from two of the first phantom and the second phantom with respect to the wire phantom, and the resolution may be evaluated by reconstructing the ultrasound signal as an image (B-mode image). In the second phantom, the image contrast performance evaluation is performed by looking at the boundary and contrast between the biological tissue imitation medium and the low acoustic pillar (ie, the pillar that appears black without reflection), and between the biological tissue imitation medium and the control target on the ultrasound signal. It can be evaluated by how much the contrast of the image signal appears and whether it is clearly seen.

The comparative analysis module 430 according to the present embodiment has the effect of analyzing the performance of the ultrasonic probe in various ways through direct comparison of the ultrasound image in the complete underwater environment and the ultrasound image in the tissue simulation environment. In this regard, it is possible to evaluate the quantitative signal degradation level by comparing the maximum performance of the rotary ultrasonic transducer in the underwater environment and the attenuated signal in the tissue-simulating environment, thereby enabling the performance evaluation of the complex ultrasonic transducer. The comparison and analysis module 430 may receive ultrasound signals (RF signals) obtained from the first phantom and the second phantom, convert them into image signals, respectively, compare the contrasts in these images, and present the difference. To this end, the comparison analysis module 430 may include circuit blocks such as a filter, an envelope detector, and a normalizer.

And, as described above, there is an effect that the resolution performance of the high-frequency ultrasonic transducer can be evaluated through the wire target for high-precision resolution analysis. Based on the high-density target for resolution evaluation, there is an advantage that can greatly help the evaluation and development of high-frequency ultrasonic transducers with high resolution performance.

2 is a plan view illustrating a phantom for underwater measurement of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention. As shown in FIG. 2, the phantom 200 for underwater measurement uses an acoustic reflector 210 that draws an arc having the same center as the rotary ultrasonic transducer, pulse-echo performance evaluation of the rotary ultrasonic transducer can be performed. .

3 is an isometric view showing a phantom for underwater measurement of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention. The ultrasonic beam pattern of the rotary ultrasonic probe fixed to the phantom can be measured by placing a wide empty space 220 without an outer wall to connect the hydrophone to the phantom for underwater measurement from the outside.

By fixing a desired target to the empty space 220 of the phantom for underwater measurement, it is also possible to evaluate the image performance of an arbitrary target of the rotary ultrasonic transducer fixed to the phantom.

According to an embodiment of the present invention, the wire target may be arranged according to various intervals and positions for spatial resolution evaluation of the rotary ultrasonic transducer. For example, a wire target (T) with a spacing of 90 degrees on the outside of the phantom for underwater measurement and a wire target with intervals of 1, 2, 3, 4, 5 degrees and 0.5, 1, 2, 3, 4, 5 mm on the inside It can be placed at 12mm, 15mm, 18mm or 20mm from the center. Through such a high-precision wire target arrangement, it becomes possible to evaluate the spatial resolution of the rotary ultrasonic transducer.

4 and 5 are a plan view and an isometric view showing a tissue-simulating phantom of a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention. In the case of the tissue-simulating phantom, a rotary ultrasonic transducer places a low-acoustic column and a contrast target of the ultrasound image at a predetermined interval in a tissue-simulating environment to evaluate the low-acoustic imaging performance and the contrasting performance.

According to an embodiment of the present invention, even in the second phantom, the wire target may be arranged at various intervals and positions for spatial resolution evaluation of the rotary ultrasonic transducer. For example, a wire target (T) with a spacing of 90 degrees on the outside of the tissue-simulating phantom and a wire target with intervals of 1, 2, 3, 4, 5 degrees and 0.5, 1, 2, 3, 4, 5 mm on the inside are centered It can be placed at 12mm, 15mm, 18mm, and 20mm from There is an advantage in that it is easy to evaluate the spatial resolution of a high-performance rotary ultrasonic transducer through such a high-precision wire target arrangement.

In the performance evaluation method using a multi-purpose ultrasonic phantom according to an embodiment of the present invention, image analysis and comparison are largely three ((1) pulse-echo test using an acoustic reflector, (2) ultrasonic rotation image acquisition, (3) ultrasound beam pattern analysis).

In the pulse-echo test using the acoustic reflector, a strong ultrasonic pulse signal is applied to the acoustic reflector 210 and the maximum signal received from the transducer is measured.

In the ultrasonic rotation image acquisition, a rotation image (or otherwise called a phantom horizontal cross-sectional image) is obtained for 200 and 300 having the same frame and target. This ultrasonic rotation image can also serve as the above pulse-echo test. In the phantom 200 for underwater measurement, it is possible to see the image of the target in water with little ultrasonic reflection and noise, and the distance between the targets in the image. In the tissue-simulating phantom 300 , in a situation in which noise or a small echo is generated by the tissue-simulating phantom medium in which ultrasonic reflection occurs, the distance or the intensity of the echo can be seen by viewing the image of the target. It can also be seen how well the low acoustic column 310 and the contrast target 320 are distinguished from the medium.

Ultrasonic beam pattern analysis is measured by placing a hydrophone in an empty space in the phantom for underwater measurement. In this case, rotational images are not generally taken.

In general, the test cases to be analyzed and compared can all be made under different conditions. In order to make all of the above (1), (2), and (3) be performed under different conditions, it is necessary to acquire three signals in the first phantom and acquire signals one in the second phantom. In summary, in the (1) acoustic reflection plate pulse-echo test, the acoustic reflection plate 210 of the first phantom may be applied, and the second phantom may not be applied. (2) The ultrasonic rotation image acquisition is applied to the target T of the first phantom 200, and the target T, (310), (320), (+tissue) of the second phantom in the second phantom 300 simulated phantom medium). (3) The ultrasound beam pattern analysis may be applied to 220 of the first phantom 200 .

In case of (1), ultrasonic pulses with high voltage and short time intervals are usually used. However, in order to analyze the pulse-echo results for the actual image shooting environment as in (2), the rotation image signal corresponding to (2) can be measured and used for the analysis of (1). . This will be described with reference to FIG. 6 .

6 is a flowchart illustrating a performance evaluation method using a multi-purpose ultrasonic phantom according to an embodiment of the present invention. As shown in FIG. 6 , in a performance evaluation method using a multi-purpose ultrasonic phantom including an ultrasonic transducer, a first phantom, a second phantom, and an analysis unit, the analysis unit is externally connected to the hydrophone in an underwater environment to the first phantom can evaluate the ultrasound image of the ultrasound transducer.

In the first phantom evaluation step according to the present embodiment, the analysis unit evaluates the ultrasonic signal penetration depth of axial and lateral resolution while rotating the ultrasonic probe located in the center of the first phantom in the axial direction or in the lateral direction. Evaluating the pulse-echo performance of the rotary ultrasonic transducer using an acoustic reflector that draws an arc having the same center as that of the rotary ultrasonic transducer of the first phantom by the analysis unit, and the analysis unit connects the hydrophone to the first phantom from the outside and measuring an ultrasonic beam pattern of a rotary ultrasonic transducer fixed to a wide empty space without an outer wall to make it possible.

Next, the analysis unit positions the ultrasound transducer in the center of the second phantom, and the contrast target of the ultrasound image is arranged at a predetermined interval, and the low acoustic column of the second phantom and the contrast target of the ultrasound image are placed at a predetermined interval. Evaluate low-acoustic imaging performance. In this second phantom evaluation step, the analysis unit measures the ultrasonic beam pattern of the rotary ultrasonic probe with respect to an arbitrary target fixed to the tissue-simulating phantom, and evaluates the ultrasonic signal penetration depth of the axial and lateral resolution of the rotary ultrasonic probe. And in this evaluation step, the analysis unit includes a step of evaluating the low acoustic image performance and the contrast performance by placing a low acoustic column and a contrast target of the ultrasound image at a predetermined interval in the second phantom.

Next, the analysis unit compares and analyzes the image performance by the first phantom and the image performance by the second phantom.

In detail, the performance evaluation method using the ultrasonic phantom of the present invention is obtained by arranging an ultrasonic transducer in the center of the first phantom and then rotating it to obtain a signal to obtain an ultrasonic signal for 360 degrees. Pulse-echo performance evaluation is possible with the ultrasonic signal obtained at this time. Also, by restoring the above signal to a B-mode image, an image for comparative analysis can be obtained. In addition, the ultrasonic beam pattern may be measured by aligning the ultrasonic transducer's ultrasonic direct direction toward the empty space and arranging the hydrophone in the empty space.

At this time, the hydrophone can move to various locations in space based on a precision motor, measure the ultrasonic signal generated by the ultrasonic probe, and restore the beam through software. That is, it is possible to use a beam analysis technique through a hydrophone, and for this, the first phantom of the present invention may have a space to easily analyze the performance of the rotating ultrasonic transducer.

In addition, after positioning the ultrasonic transducer in the center of the second phantom, the signal is obtained while rotating to obtain an ultrasonic signal for 360 degrees. In this case, an ultrasound image may be obtained by restoring the acquired ultrasound signal to the B mode, and it may be compared and analyzed together with the image of the first phantom. In addition, in the restored B-mode image, the contrast performance of the image may be evaluated through a portion having a low acoustic column and a contrast target rather than a wire target.

In summary, the ultrasonic transducer is positioned in the first phantom, the first signal for pulse-echo performance evaluation is obtained from the acoustic reflector, and the ultrasonic rotation image is obtained from the ultrasonic transducer fixed to the first phantom of the target (T). Acquire a second signal for analysis. In order to analyze the ultrasonic beam pattern of the ultrasonic probe fixed to the first phantom, a hydrophone is attached to the empty space 220 to obtain a third ultrasonic beam pattern signal. The reason for separating them is that the hydrophone is generally a highly sensitive device, so it should not be connected when acquiring an image. The measurement method is different from the rotation image. Simply put, the empty space is a space for connecting an external measuring device and may not always be available.

Next, a signal for analyzing an ultrasonic beam pattern for analyzing a target, a low acoustic column, and a control target is acquired by positioning an ultrasonic transducer in the second phantom and acquiring an ultrasonic rotation image.

Next, the ultrasonic probe (of the probe itself) performance is evaluated through the pulse-echo performance evaluation/ultrasonic beam pattern signal obtained from the first phantom, and the image performance by the first phantom and the image performance by the second phantom are compared and analyzed. .

Hereinafter, an ultrasonic phantom device for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention will be described in detail with reference to FIGS. 7 to 9 .

7 is a view for explaining the characteristics of the transducer and sound wave according to an embodiment of the present invention. 7 shows a phenomenon in which the gray area increases as the transducers move toward the right and moves away from the center. Here, the gray area is an area where the ultrasound is sufficiently focused to obtain a relatively accurate signal, and the center point of the gray space can be seen as the focal length. seems to be the case As an ultrasonic signal, sound wave has a certain degree of directivity like light, but spreads more easily than light. Physically, characteristics such as a frequency value at which ultrasound is most efficiently generated), focal length, and degree of focus (curvature, depth of focus) may vary.

In the multi-purpose ultrasonic phantom device for performance evaluation of a rotary ultrasonic transducer according to an embodiment of the present invention, the wire target angle and spacing principle will be described as follows. In the angle and spacing arrangement proposed in the present application, the absolute position can be clearly known through the targets of uniform spacing, and this can be compared with the actual image. For example, by arranging the same wire targets at points 12 mm, 15 mm, 18 mm, and 20 mm from the center, information on the above-described focusing degree can be compared.

As an example, if the focusing point is 15 mm, and there is an ultrasonic transducer capable of discriminating an interval of about 2 mm from the focusing point, such a transducer may overlap the signals of wires separated by 1 mm for wire targets located at 15 mm. It is difficult to distinguish them, and wires with a gap of 2 mm or more are clearly distinguished in the image, so a normal image can be obtained. If the depth of focus is deep, the wire target discrimination performance will be high even at 12 mm and 18 mm points, and in this case, an interval of 2 mm or more may be distinguished. However, if the depth of focus is not deep enough, for the wires at 12 and 18 mm, even wires with a gap of 2 mm are blurred or overlapped in the ultrasound image, making it difficult to distinguish them.

8 is a diagram illustrating a linear B-mode image. As shown in FIG. 8 , in a general linear brightness mode image (linear B-mode image), the ultrasonic transducer is obtained by moving the ultrasonic transducer perpendicular to the direct ultrasonic direction. If you simply look at only one ultrasonic signal, you can see how far the signal is from the ultrasonic transducer in the vertical direction (the direction in which the ultrasonic wave travels straight). In the image, these ultrasonic signals become lines, and several such lines overlap to form a plane.

9 is a view for explaining a rotational ultrasound image according to an embodiment of the present invention. As shown in Fig. 9, in the case of the rotary ultrasonic transducer, unlike the case of Fig. 8, the ultrasonic transducer rotates. In simple terms, it can be understood as creating a circular image by gathering the upper part as the center, turning the lower part outward, and attaching both ends of the image in the previous linear B-mode image. However, in this case, it is affected by the distance and angle, and the closer to the center, the smaller it appears, and the further outward, the greater the distance between the signals and appears to stretch.

In order to analyze the image of the rotary ultrasonic transducer of the present invention, a wire target fixed at a predetermined position is required, and by disposing them in various ways (closer or farther) from the center (position of the ultrasonic transducer), the focal length and depth of focus of the transducer , spatial resolution at the focal point (straight direction of ultrasound signal/rotation direction in ultrasound rotation image), etc. can be analyzed. If similar patterns are placed at various distances from the center, good performance at the optimal distance (focal length) can be evaluated, and how much performance degradation occurs when the distance from the optimal distance is further away. The target may be arranged at different distance intervals according to the required distance intervals.

In general, an ultrasound signal is RF data and may be understood as a voltage signal according to time. Such RF data appears in a form in which a voltage oscillates around a reference value (eg, a value between -1 V and +1 V based on 0 V). This is usually called A-mode (amplitude mode). To make it into an image, it must be converted to B-mode (brightness mode). In this case, filtering, envelope detection, etc. are performed, and normalization is performed. For example, in an 8-bit image, the part with the least ultrasonic signal (lowest vibration or noise) is 0, and the part where the ultrasonic signal is strongest (vibration and amplitude) is represented by 255 (2^8 - 1). , can be expressed as a video signal with a maximum brightness of 255. The image created in this way is called a B-mode image.

If an ultrasound image signal is obtained for a phantom having accurate distance and location information and then restored as above, the actual physical location and the ultrasound signal can be compared. At this time, the spatial resolution of the ultrasonic transducer can be evaluated by checking whether the wires arranged at intervals of 1mm, 2mm, 3mm, etc. are distinguished from the actual image. For example, it can be checked whether two wire targets close to the naked eye are distinguished.

In more detail, the axial resolution (axial resolution - the ultrasonic straight direction) is expressed by Equation 1 below.

[Equation 1]

Axial resolution = Spatial Pulse length / 2 or (# cycles in the pulse * wavelength)/2

The ultrasonic radiation signal is generally called a pulse, and the wavelength of the pulse can be determined according to the frequency, and half of this wavelength is generally the axial resolution. The number of cycles is the number of times that one pulse is continuously irradiated. At this time, the returned ultrasound signal also increases as much, so that the resolution is lowered by the number of cycles.

Lateral resolution is the resolution in the vertical direction. In general, it is affected by the ultrasonic beam width, and the beam width is affected by the diameter or focusing degree of the ultrasonic transducer. You will see the performance of how close objects can be distinguished from the focal length.

The present invention described above is not limited by the above-described embodiments and the accompanying drawings, and it will be apparent to those skilled in the art that various substitutions, modifications and changes are possible without departing from the technical spirit of the present invention.

100: rotary ultrasonic transducer 200: phantom for underwater measurement
210: acoustic reflector 220: empty space part
300: tissue simulation phantom 310: low acoustic column
320: control target 400: analysis unit
410: pulse-echo performance evaluation module 420: beam pattern measurement module
430: comparative analysis module

Claims (15)

ultrasonic transducer,
A first phantom for evaluating the ultrasound image of the ultrasound transducer in an underwater environment;
a second phantom in which the ultrasonic transducer is disposed and a contrast target of the ultrasound image is disposed at a predetermined interval; and
Multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer, characterized in that it includes an analysis unit for evaluating the ultrasonic signal penetration depth of the ultrasonic transducer and comparing the image performance by the first phantom and the image performance by the second phantom .
According to claim 1,
The ultrasonic transducer is a multi-purpose ultrasonic phantom for performance evaluation of the rotary ultrasonic transducer, characterized in that the rotary ultrasonic transducer.
According to claim 1,
The first phantom is a multipurpose ultrasonic phantom for performance evaluation of a rotary ultrasonic probe, characterized in that it is a phantom for underwater measurement for connecting a hydrophone in an underwater environment from the outside and evaluating the ultrasonic image of the ultrasonic probe.
According to claim 1,
The first phantom is a multipurpose for performance evaluation of a rotary ultrasonic transducer, characterized in that it has a wide empty space without an outer wall to connect an acoustic reflector and a hydrophone that draws an arc having the same center as the rotary ultrasonic transducer from the outside. Ultrasonic Phantom.
According to claim 1,
The second phantom is a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer, characterized in that it is a tissue-simulating phantom for evaluating the performance according to the tissue-simulating environment.
According to claim 1,
The second phantom is a multi-purpose ultrasonic phantom for performance evaluation of a rotary ultrasonic transducer, characterized in that it includes a plurality of contrast targets arranged at a predetermined interval between a low-acoustic column for fixing the rotary ultrasonic transducer and a contrast target of the ultrasonic image.
The method of claim 1,
The analysis unit
Pulse-echo performance evaluation module of the rotary ultrasonic transducer using an acoustic reflector that draws an arc having the same center as the rotary ultrasonic transducer of the first phantom.
According to claim 1,
The analysis unit
A first beam pattern measuring module for measuring an ultrasonic beam pattern of a rotary ultrasonic probe fixed to a wide empty space without an outer wall so as to connect a hydrophone to the first phantom from the outside;
A second beam pattern measuring module for measuring the ultrasonic beam pattern of the rotary ultrasonic probe with respect to an arbitrary target fixed to the second phantom to evaluate the ultrasonic signal penetration depth of the axial and lateral resolution of the rotary ultrasonic probe Multipurpose ultrasonic phantom for performance evaluation of rotating ultrasonic transducers.
According to claim 1,
The analysis unit
Performance of a rotary ultrasonic transducer, characterized in that it comprises a comparative analysis module for evaluating the low-acoustic image performance and the contrast performance by placing a low-acoustic column and a contrast target of the ultrasound image at a predetermined interval in the second phantom Versatile ultrasonic phantom for evaluation.
According to claim 1,
Any one or more of the first phantom and the second phantom is a wire target on the outside and two or more wire targets having a predetermined interval on the inside. Versatile ultrasonic phantom for evaluation.
In the performance evaluation method using a multi-purpose ultrasonic phantom including an ultrasonic transducer, a first phantom, a second phantom and an analysis unit,
a first evaluation step in which the analysis unit evaluates the ultrasound image of the ultrasound transducer in an underwater environment on the first phantom;
a second evaluation step in which the analyzer evaluates the ultrasound image performance of the ultrasound probe in the second phantom in which a contrast target of a low acoustic column and an ultrasound image is arranged at a predetermined interval; and
and comparing and analyzing, by the analysis unit, the image performance by the first phantom and the image performance by the second phantom.
12. The method of claim 11,
The first evaluation step is a performance evaluation method using a multi-purpose ultrasonic phantom, characterized in that it comprises the step of the analyzer evaluating the ultrasonic signal penetration depth of the axial and lateral resolution of the ultrasonic probe in the first phantom.
12. The method of claim 11,
In the first evaluation step, the analysis unit evaluates the pulse-echo performance of the rotary ultrasonic transducer using an acoustic reflector that draws an arc having the same center as that of the rotary ultrasonic transducer of the first phantom;
Performance evaluation method using a multi-purpose ultrasonic phantom, characterized in that it comprises the step of measuring the ultrasonic beam pattern of the rotary ultrasonic probe in a wide empty space without an outer wall so that the analyzer can connect the hydrophone to the first phantom from the outside .
12. The method of claim 11,
The second evaluation step is a performance evaluation method using a multi-purpose ultrasonic phantom, characterized in that it comprises the step of the analysis unit evaluating the ultrasonic signal penetration depth of the axial and lateral resolution of the ultrasonic probe in the second phantom.
12. The method of claim 11,
The second evaluation step is a multi-purpose, characterized in that it comprises the step of the analysis unit performing the evaluation of the low acoustic image performance and the contrast performance by placing the low acoustic column and the contrast target of the ultrasound image in the second phantom at a predetermined interval Performance evaluation method using ultrasonic phantom.

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