Ultrasound Technology in Industry and Medicine

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Acoustics and Vibrations".

Deadline for manuscript submissions: closed (10 August 2022) | Viewed by 37129

Special Issue Editor


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Guest Editor
Department of Acoustics and Multimedia, Faculty of Electronics, Wroclaw University of Science and Technology, 50-370 Wrocław, Poland
Interests: ultrasound technique; ultrasonic transducers; ultrasonic measurements and ultrasonic diagnostics; ultrasound imaging; application of ultrasound in technology, industry, and medicine; sound production; processing of acoustic signals

Special Issue Information

Dear Colleagues,

At present, the number of ultrasound applications is constantly growing in the form of new, innovative methods and devices. The use of ultrasound technologies began to spread in industry and medicine in the 1970s. Ultrasonic waves are used to detect and characterize the elastic properties of objects in any type of medium (except vacuum): gas, liquid, or solid. They have relatively low speed and effectively propagate both in the human body and in metal objects (unlike electromagnetic waves), which is a very useful feature in measurements and imaging (ultrasonic sensors, biometry, non-destructive testing, liquid and gas flow measurements, sonars, echo sounders, B-mode echography, elastography, tomography, intravascular imaging, microscopy). The safety associated with ultrasound propagation is generally high compared to X-rays, and measurements and imaging can be performed with cheaper devices than other methods. Additionally, important applications for ultrasound include micro-mechanical systems (MEMS and CMUT arrays), ultrasonic motors and sensors, as well as signal processing systems on surface waves. Ultrasonic waves can also transmit significant mechanical energy, which is used for material processing (cleaning, soldering, welding, drilling, spraying, creating emulsions, accelerating chemical reactions) and in surgery and medical therapy (cavitation cutting of tissues, drilling of bones and teeth, tartar removal, breaking down fat cells and kidney stones, thermal destruction of cancer, phonophoresis, aerosol therapy).

Topics of interest to be covered by this Special Issue include new and innovative methods and applications of ultrasound technology in industry and medicine.

Prof. Dr. Krzysztof Opieliński
Guest Editor

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Keywords

  • ultrasound industrial application
  • ultrasound medical application
  • ultrasonic measurements
  • ultrasonic sensors, transducers, and arrays
  • ultrasonic devices and methods
  • ultrasonic signal processing systems
  • ultrasonic NDT
  • ultrasonic imaging
  • power ultrasonics
  • ultrasound in surgery and therapy

Published Papers (14 papers)

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Editorial

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4 pages, 174 KiB  
Editorial
Special Issue on Ultrasound Technology in Industry and Medicine
by Krzysztof J. Opieliński
Appl. Sci. 2023, 13(3), 1455; https://doi.org/10.3390/app13031455 - 22 Jan 2023
Viewed by 933
Abstract
As early as 1774, the application of ultrasound in the animal world was noted by the Italian naturalist Lazzaro Spallanzani, who discovered that bats move using ultrasonic waves [...] Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)

Research

Jump to: Editorial

7 pages, 1019 KiB  
Article
Effect of Depth on Ultrasound Point Shear Wave Elastography in an Elasticity Phantom
by Fahad F. Almutairi, Rawan Abdeen, Jaber Alyami and Salahaden R. Sultan
Appl. Sci. 2022, 12(13), 6295; https://doi.org/10.3390/app12136295 - 21 Jun 2022
Cited by 6 | Viewed by 1460
Abstract
Background: Phantom studies are widely used to assess variability in measurements. This study aimed to assess the reliability and accuracy of point Shear Wave elastography (pSWE) measurements of an elasticity phantom. Methods: Measurements were obtained by an experienced certified clinical sonographer at three [...] Read more.
Background: Phantom studies are widely used to assess variability in measurements. This study aimed to assess the reliability and accuracy of point Shear Wave elastography (pSWE) measurements of an elasticity phantom. Methods: Measurements were obtained by an experienced certified clinical sonographer at three different depth levels in kPa, using a curvilinear 5-1MHz transducer of the EPIQ7 ultrasound imaging system. Results: A total of 180 pSWE measurements were obtained at three different depth levels (three cm, five cm, and seven cm) of the phantom background. The mean CV of pSWE was low at all depths (3 cm: 8.8%; 5 cm: 7%; 7 cm: 7.2%). There was a significant difference between measurements at depths of 3 cm vs. 7 cm (MD: −0.85, 95% CI −1.5, −0.11, p = 0.024) and measurements at depths 5 cm vs. 7 cm (MD: −1.1, 95% CI −1.7, −0.47, p = 0.001). An overestimation of mean pSWE measurements at a depth of 7 cm was noted compared to the manufacturer’s value (2.7%, p = 0.006). Conclusions: Superficial phantom SWE measurements in this study had low variability compared to deep measurement. pSWE measurements at deep levels can be overestimated. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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15 pages, 3852 KiB  
Article
Temporal Evolution of Refractive Index Induced by Short Laser Pulses Accounting for Both Photoacoustic and Photothermal Effects
by Zhiying Xia, Bin Ni, Ruijie Hou, Yang Zhang, Lianping Hou, Jamie Jiangmin Hou, John H. Marsh, Xuefeng Liu and Jichuan Xiong
Appl. Sci. 2022, 12(12), 6256; https://doi.org/10.3390/app12126256 - 20 Jun 2022
Cited by 2 | Viewed by 1572
Abstract
Materials such as silicon, copper, gold, and aluminum exhibit strong absorption and scattering characterization under short-pulsed laser irradiation. Due to the photoelastic effect and thermoelastic relaxation, the focal area may induce a local modulation in the refractive index, which can be detected with [...] Read more.
Materials such as silicon, copper, gold, and aluminum exhibit strong absorption and scattering characterization under short-pulsed laser irradiation. Due to the photoelastic effect and thermoelastic relaxation, the focal area may induce a local modulation in the refractive index, which can be detected with the intensity reflection coefficient perturbation. Normally, the thermal effect causes a weak refractive index change and is negligible, compared with the pressure-induced effect in most photoacoustic analytical systems. In this study, we present a theoretical model with the whole process of absorbed energy conversion analysis for the refractive index perturbation induced by both thermal effect and photoacoustic pressure. In this model, data analysis was carried out on the transformation of the energy absorbed by the sample into heat and stress. To prove the feasibility of this model, numerical simulation was performed for the photothermal and photoacoustic effects under different incident intensities using the finite element method. Experiment results on silicon and carbon fiber verified that the refractive index change induced by the photothermal effect can be detected and be incorporated with pressure-induced refractive index change. The simulation results showed very good agreement with the results of the experiments. The main aim of this study was to further understand the absorption and conversion process of short-pulsed light energy and the resulting photothermal and photoacoustic effects. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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24 pages, 4794 KiB  
Article
Shear Wave Elastography Implementation on a Portable Research Ultrasound System: Initial Results
by Damian Cacko and Marcin Lewandowski
Appl. Sci. 2022, 12(12), 6210; https://doi.org/10.3390/app12126210 - 18 Jun 2022
Cited by 4 | Viewed by 4492
Abstract
Ultrasound shear wave elastography (SWE) has emerged as a promising technique that enables the quantitative estimation of soft tissue stiffness. However, its practical implementation is complicated and presents a number of engineering challenges, including high-energy burst transmission, high-frame rate data acquisition and high [...] Read more.
Ultrasound shear wave elastography (SWE) has emerged as a promising technique that enables the quantitative estimation of soft tissue stiffness. However, its practical implementation is complicated and presents a number of engineering challenges, including high-energy burst transmission, high-frame rate data acquisition and high computational requirements to process huge datasets. Therefore, to date, SWE has only been available for high-end commercial systems or bulk and expensive research platforms. In this work, we present a low-cost, portable and fully configurable 256-channel research system that is able to implement various SWE techniques. We evaluated its transmit capabilities using various push beam patterns and developed algorithms for the reconstruction of tissue stiffness maps. Three different push beam generation methods were evaluated in both homogeneous and heterogeneous experiments using an industry-standard elastography phantom. The results showed that it is possible to implement the SWE modality using a portable and cost-optimized system without significant image quality losses. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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11 pages, 2839 KiB  
Article
Multiparameter Analysis of the Ultrasonic Transducer Transfer Function Using a Genetic Algorithm
by Tadeusz Gudra and Dariusz Banasiak
Appl. Sci. 2022, 12(11), 5325; https://doi.org/10.3390/app12115325 - 25 May 2022
Cited by 2 | Viewed by 1365
Abstract
The transfer function is an important parameter describing ultrasonic transducers which are designed to operate in various media. The typically high impedance of piezoelectric transducers is matched to a particular loading medium (gas, liquid, biological medium) by using multicomponent matching layers, which have [...] Read more.
The transfer function is an important parameter describing ultrasonic transducers which are designed to operate in various media. The typically high impedance of piezoelectric transducers is matched to a particular loading medium (gas, liquid, biological medium) by using multicomponent matching layers, which have specific impedances and thicknesses in accordance with the generally known matching criteria: Chebyshev, DeSilets or Souquet. When properly selected, the materials used for the matching layers allow the most optimal parameters to be obtained for both transmitting and the receiving ultrasonic energy. However, studies rarely focus on the possibility of shaping the obtained transfer function, which is also a parameter that is important in some applications of transducers intended for pulse operation, especially in liquid media (e.g., in hydroacoustics) or in biological media (e.g., in ultrasound imaging). The values and shapes of such a function are influenced by factors which are identical to the parameters describing the matching layers. This article presents the possibilities and advantages of using a genetic algorithm to shape the characteristics of the transfer functions that have a particular importance in the search for an optimal (typically the greatest) bandwidth of a transducer intended for operation in a particular medium. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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11 pages, 19819 KiB  
Article
An Experimental Ultrasound Database for Tomographic Imaging
by Stefano Franceschini, Michele Ambrosanio, Angelo Gifuni, Giuseppe Grassini and Fabio Baselice
Appl. Sci. 2022, 12(10), 5192; https://doi.org/10.3390/app12105192 - 20 May 2022
Cited by 2 | Viewed by 1367
Abstract
In the framework of non-destructive testing and imaging, ultrasound tomography can have an important role in several applications, especially in the biomedical field. The motivation beyond the use of this imaging technique lies in the possibility of obtaining quantitative imaging which is also [...] Read more.
In the framework of non-destructive testing and imaging, ultrasound tomography can have an important role in several applications, especially in the biomedical field. The motivation beyond the use of this imaging technique lies in the possibility of obtaining quantitative imaging which is also operator-independent, conversely to conventional approaches. Thus, the need for public data sets for testing inverse scattering approaches is always persisting. To this aim, this paper introduces an experimental multiple-input-multiple-output ultrasound tomographic database whose acquisitions were performed by an air-matched in-house system designed and built by the Authors. The proposed database provides several cases with single and multiple objects of different shapes, sizes, and materials, to be imaged in laboratory-controlled conditions. Therefore, these scenarios can represent interesting options for the preliminary testing of tomographic ultrasound imaging approaches. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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25 pages, 11596 KiB  
Article
Analysis of the Refraction Effect in Ultrasound Breast Tomography
by Krzysztof J. Opieliński, Mariusz Bułkowski, Andrzej Gabryel and Andrzej Wiktorowicz
Appl. Sci. 2022, 12(7), 3578; https://doi.org/10.3390/app12073578 - 31 Mar 2022
Cited by 2 | Viewed by 1668
Abstract
Ultrasound breast tomography (UBT) is a promising quantitative imaging method. It allows for precise analysis of ultrasound velocity distribution, which is related to tissue density and elasticity, enabling cancer detection. Only a few centers around the world have a prototype of the device [...] Read more.
Ultrasound breast tomography (UBT) is a promising quantitative imaging method. It allows for precise analysis of ultrasound velocity distribution, which is related to tissue density and elasticity, enabling cancer detection. Only a few centers around the world have a prototype of the device for in vivo breast ultrasound tomography imaging. The quality of images reconstructed from measurements of ultrasound pulse transit times is adversely affected by the refraction of beam rays on the breast immersed in water. Refraction can be reduced using waveform tomography, ray-tracing, and ray-linking methods. However, this requires the acquisition of a pre-reconstructed pattern and is limited by extreme computational costs. In this study, the effect of refraction on transit time measurements of ultrasound passing through the female breast was analyzed under immersion conditions in water. It was found that the refraction causes the highest measurement errors in the area of the water/breast interface, and these can be reduced by adjusting the water temperature and changing the breast geometry. The results allow us to improve the quality of breast images reconstructed using an efficient transformation algorithm that assumes rectilinear ultrasound propagation paths between transmitters and receivers. In vivo breast studies were performed on the developed hybrid UBT scanner. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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10 pages, 779 KiB  
Article
Low-Cost Underwater Communication System: A Pilot Study
by Boguslaw Szlachetko
Appl. Sci. 2022, 12(7), 3287; https://doi.org/10.3390/app12073287 - 24 Mar 2022
Cited by 2 | Viewed by 2447
Abstract
The aim of the paper is to present a simplified implementation of quadrature phase shift keying (QPSK) based underwater communication system. The presented solution addresses the problem of developing inexpensive, compact ultrasound modems able to be mounted on underwater robots. Simplifications introduced into [...] Read more.
The aim of the paper is to present a simplified implementation of quadrature phase shift keying (QPSK) based underwater communication system. The presented solution addresses the problem of developing inexpensive, compact ultrasound modems able to be mounted on underwater robots. Simplifications introduced into the modulation and demodulation of QPSK signals do not disturb any parameter of the data link. The paper indicates that it is possible to realize modulation and demodulation on a simple microcontroller. Many hints are given on how to use hardware blocks embedded in a microcontroller, such as ADC, DMA, timers, etc. Experiments performed with the prototype modems allow to reach 4 kbps data rate on a distance of about 18 m. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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19 pages, 19393 KiB  
Article
Different Types of Ultrasound Probes Usage for Multi-Angle Conventional 3D Ultrasound Compound Imaging: A Breast Phantom Study
by Maciej Sabiniok and Krzysztof J. Opieliński
Appl. Sci. 2022, 12(5), 2689; https://doi.org/10.3390/app12052689 - 04 Mar 2022
Cited by 2 | Viewed by 6168
Abstract
Three-dimensional automated breast ultrasound (ABUS) systems seem to offer excellent results in breast cancer screening tests and its early detection, comparable to handheld ultrasound B-mode scanning, with the benefit of saving physician time and reducing handheld ultrasound issues. Nevertheless, the ABUS systems are [...] Read more.
Three-dimensional automated breast ultrasound (ABUS) systems seem to offer excellent results in breast cancer screening tests and its early detection, comparable to handheld ultrasound B-mode scanning, with the benefit of saving physician time and reducing handheld ultrasound issues. Nevertheless, the ABUS systems are not very popular, due to the cost and very narrow application. The multi-angle conventional 3D ultrasound compound imaging method (MACUI) is intended for use with standard B-mode scanners in order to reduce cost but preserve the advantages of ABUS systems. The rotational probe movement is utilized in order to collect images for the three-dimensional reconstruction of the scanned tissue’s anatomy. The authors evaluate the capabilities to increase the scanned volume and quality of reconstructions, which are limited in current MACUI implementations, with a probe tilt and shift. The study shows and discusses the results of the imaging using different probes available for SmartUs Telemed B-Mode scanner at different scanning geometry in order to determine the capabilities of such an ultrasound imaging system. The results discussed in the paper highlight the benefits in quality improvement and scanning area obtained with tilted and shifted probes, as well as the advantages of using a relatively simple convex probe that does not incorporate software beam steering over more advanced devices. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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14 pages, 4590 KiB  
Article
Acoustic-Field Beamforming-Based Generalized Coherence Factor for Handheld Ultrasound
by Chang-Lin Hu, Chien-Ju Li, I-Cheng Cheng, Peng-Zhi Sun, Brian Hsu, Hsiao-Hsuan Cheng, Zhan-Sheng Lin, Chii-Wann Lin and Meng-Lin Li
Appl. Sci. 2022, 12(2), 560; https://doi.org/10.3390/app12020560 - 06 Jan 2022
Cited by 2 | Viewed by 1641
Abstract
Handheld ultrasound devices have been widely used for diagnostic applications. The use of the acoustic-field beamforming (AFB) method has been proposed for handheld ultrasound to reduce electricity consumption and avoid battery and unwanted heat issues. However, the image quality, such as the contrast [...] Read more.
Handheld ultrasound devices have been widely used for diagnostic applications. The use of the acoustic-field beamforming (AFB) method has been proposed for handheld ultrasound to reduce electricity consumption and avoid battery and unwanted heat issues. However, the image quality, such as the contrast ratio and contrast-to-noise-ratio, are poorer with this technique than with the conventional delay-and-sum method. To address the problems associated with the worse image quality in AFB imaging, in this paper we propose the use of an AFB-based generalized coherence factor (GCF) technique, in which the GCF weighting developed for adaptive beamforming is extended to AFB. Simulation data, experimental results, and in vivo testing verified the efficacy of our proposed AFB-based GCF technique. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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21 pages, 1689 KiB  
Article
Object Localization and Tracking System Using Multiple Ultrasonic Sensors with Newton–Raphson Optimization and Kalman Filtering Techniques
by Chung-Wei Juan and Jwu-Sheng Hu
Appl. Sci. 2021, 11(23), 11243; https://doi.org/10.3390/app112311243 - 26 Nov 2021
Cited by 7 | Viewed by 2219
Abstract
In this paper, an object localization and tracking system is implemented with an ultrasonic sensing technique and improved algorithms. The system is composed of one ultrasonic transmitter and five receivers, which uses the principle of ultrasonic ranging measurement to locate the target object. [...] Read more.
In this paper, an object localization and tracking system is implemented with an ultrasonic sensing technique and improved algorithms. The system is composed of one ultrasonic transmitter and five receivers, which uses the principle of ultrasonic ranging measurement to locate the target object. This system has several stages of locating and tracking the target object. First, a simple voice activity detection (VAD) algorithm is used to detect the ultrasonic echo signal of each receiving channel, and then a demodulation method with a low-pass filter is used to extract the signal envelope. The time-of-flight (TOF) estimation algorithm is then applied to the signal envelope for range measurement. Due to the variations of position, direction, material, size, and other factors of the detected object and the signal attenuation during the ultrasonic propagation process, the shape of the echo waveform is easily distorted, and TOF estimation is often inaccurate and unstable. In order to improve the accuracy and stability of TOF estimation, a new method of TOF estimation by fitting the general (GN) model and the double exponential (DE) model on the suitable envelope region using Newton–Raphson (NR) optimization with Levenberg–Marquardt (LM) modification (NRLM) is proposed. The final stage is the object localization and tracking. An extended Kalman filter (EKF) is designed, which inherently considers the interference and outlier problems of range measurement, and effectively reduces the interference to target localization under critical measurement conditions. The performance of the proposed system is evaluated by the experimental evaluation of conditions, such as stationary pen localization, stationary finger localization, and moving finger tracking. The experimental results verify the performance of the system and show that the system has a considerable degree of accuracy and stability for object localization and tracking. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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17 pages, 5524 KiB  
Article
A Modified Wavenumber Algorithm of Multi-Layered Structures with Oblique Incidence Based on Full-Matrix Capture
by Bei Yu, Haoran Jin, Yujian Mei, Jian Chen, Eryong Wu and Keji Yang
Appl. Sci. 2021, 11(22), 10808; https://doi.org/10.3390/app112210808 - 16 Nov 2021
Cited by 6 | Viewed by 1799
Abstract
Full-matrix capture (FMC)-based ultrasonic imaging provides good sensitivity to small defects in non-destructive testing and has gradually become a mainstream research topic. Many corresponding algorithms have been developed, e.g., the total focusing method (TFM). However, the efficiency of the TFM is limited, especially [...] Read more.
Full-matrix capture (FMC)-based ultrasonic imaging provides good sensitivity to small defects in non-destructive testing and has gradually become a mainstream research topic. Many corresponding algorithms have been developed, e.g., the total focusing method (TFM). However, the efficiency of the TFM is limited, especially in multi-layered structures. Although the appearance of wavenumber algorithms, such as extended phase-shift migration (EPSM) methods, has improved imaging efficiency, these methods cannot be applied to cases with oblique incidence. Therefore, a modified wavenumber method for full-matrix imaging of multi-layered structures with oblique array incidence is proposed. This method performs a coordinate rotation in the frequency domain to adapt it to the oblique incidence. It then utilizes wave-field extrapolation to migrate the transmitting and receiving wave field to each imaging line, and a correlation imaging condition is used to reconstruct a total focused image. The proposed method can deal with any incident angle without precision loss. Moreover, it inherits the computational efficiency advantages of the wavenumber algorithms. The simulation and experimental results show that the proposed method performs better in terms of accuracy and efficiency than the TFM. Specifically, it is nearly 60 times faster than the TFM when processing an FMC dataset with a size of 4096 × 64 × 64. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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18 pages, 13059 KiB  
Article
Image-Free Ultrasound Blood-Flow Monitoring Circuit System with Automatic Range-Gate Positioning Scheme: A Pilot Study
by Hyun-Tae Park and Ji-Yong Um
Appl. Sci. 2021, 11(22), 10617; https://doi.org/10.3390/app112210617 - 11 Nov 2021
Cited by 2 | Viewed by 4623
Abstract
This work proposes a proof-of-concept ultrasound blood-flow-monitoring circuit system using a single-element transducer. The circuit system consists of a single-element ultrasonic transducer, an analog interface circuit, and a field-programmable gate array (FPGA). Since the system uses a single-element transducer, an ultrasound image cannot [...] Read more.
This work proposes a proof-of-concept ultrasound blood-flow-monitoring circuit system using a single-element transducer. The circuit system consists of a single-element ultrasonic transducer, an analog interface circuit, and a field-programmable gate array (FPGA). Since the system uses a single-element transducer, an ultrasound image cannot be reconstructed unless scanning with mechanical movement is used. An ultrasound blood-flow monitor basically needs to acquire a Doppler sample volume by positioning a range gate at a vessel region on a scanline. Most recent single-transducer-based ultrasound pulsed-wave Doppler devices rely on a manual adjustment of the range gate to acquire Doppler sample volumes. However, the manual adjustment of the range gate depends on the user’s experience, and it can be time consuming if a transducer is not properly positioned. Thus, automatic range-gate-positioning is more desirable for image-free pulsed-wave Doppler devices. This work proposes a circuit system which includes a new automatic range-gate-positioning scheme. It blindly tracks the position of a blood vessel on a scanline by using the accumulation of Doppler amplitude deviations and a hysteresis slicing function. The proposed range-gate-positioning scheme has been implemented in an FPGA for real-time operation and is based on addition-only computations, except for filter parts to reduce the complexity of computation in the hardware. The proposed blood-flow-monitoring circuit system has been implemented with discrete commercial chips for proof-of-concept purposes. It uses a center frequency of 2 MHz and a system-clock frequency of 20 MHz. The FPGA only utilizes 5.6% of slice look-up-tables (LUTs) for implementation of the range-gate-positioning scheme. For measurements, the circuit system was utilized to interrogate a customized flow phantom model, which included two vessel-mimicking channels. The circuit system successfully acquired Doppler sample volumes by positioning a range gate on a fluid channel. In addition, the estimated Doppler shift frequency shows a good agreement with the theoretical value. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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9 pages, 5012 KiB  
Article
Scanning of a Dental Implant with a High-Frequency Ultrasound Scanner: A Pilot Study
by Lauren Bohner, Daniel Habor, Klaus Radermacher, Stefan Wolfart and Juliana Marotti
Appl. Sci. 2021, 11(12), 5494; https://doi.org/10.3390/app11125494 - 14 Jun 2021
Cited by 3 | Viewed by 2803
Abstract
The purpose of this in vitro study was to assess the trueness of a dental implant scanned using an intraoral high-frequency ultrasound prototype and compared with conventional optical scanners. An acrylic resin cast containing a dental implant at position 11 was scanned with [...] Read more.
The purpose of this in vitro study was to assess the trueness of a dental implant scanned using an intraoral high-frequency ultrasound prototype and compared with conventional optical scanners. An acrylic resin cast containing a dental implant at position 11 was scanned with a fringe projection 3D sensor for use as a reference dataset. The same cast was scanned 10 times for each group. Ultrasound scanning was performed with a high-frequency probe (42 MHz, aperture diameter of 4 mm and focus length of 8 mm), and 3D images were reconstructed based on the depth of each surface point echo. Optical scans were performed in a laboratory and with an intraoral scanner. A region of interest consisting of the dental implant site was segmented and matched to the reference dataset. Trueness was defined as the closeness between experimental data and the reference surface. Statistical analysis was performed with one-way ANOVA and post-hoc tests with a significance level of p = 0.05. No statistical difference was found among the evaluated scanners. The mean deviation error was 57.40 ± 17.44 µm for the ultrasound scanner, 75.40 ± 41.43 µm for the laboratory scanner and 38.55 ± 24.34 µm for the intraoral scanner. The high-frequency ultrasound scanner showed similar trueness to optical scanners for digital implant impression. Full article
(This article belongs to the Special Issue Ultrasound Technology in Industry and Medicine)
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