• Korean Journal of Radiology
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• v.21 no.9
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• pp.1045-1054
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• 2020

Objective: This study aimed to evaluate the diagnostic value of combining the quantitative parameters of shear wave elastography (SWE) and superb microvascular imaging (SMI) to breast ultrasound (US) to differentiate between benign and malignant breast masses. Materials and Methods: A total of 200 pathologically confirmed breast lesions in 192 patients were retrospectively reviewed using breast US with B-mode imaging, SWE, and SMI. Breast masses were assessed based on the breast imaging reporting and data system (BI-RADS) and quantitative parameters using the maximum elasticity (Emax) and ratio (Eratio) in SWE and the vascular index in SMI (SMI_VI). The area under the receiver operating characteristic curve (AUC) value, sensitivity, specificity, accuracy, negative predictive value, and positive predictive value of B-mode alone versus the combination of B-mode US with SWE or SMI of both parameters in differentiating between benign and malignant breast masses was compared, respectively. Hypothetical performances of selective downgrading of BI-RADS category 4a (set 1) and both upgrading of category 3 and downgrading of category 4a (set 2) were calculated. Results: Emax with a cutoff value of 86.45 kPa had the highest AUC value compared to Eratio of 3.57 or SMI_VI of 3.35%. In set 1, the combination of B-mode with Emax or SMI_VI had a significantly higher AUC value (0.829 and 0.778, respectively) than B-mode alone (0.719) (p < 0.001 and p = 0.047, respectively). B-mode US with the addition of Emax, Eratio, and SMI_VI had the best diagnostic performance of AUC value (0.849). The accuracy and specificity increased significantly from 68.0% to 84.0% (p < 0.001) and from 46.1% to 79.1% (p < 0.001), respectively, and the sensitivity decreased from 97.6% to 90.6% without statistical loss (p = 0.199). Conclusion: Combining all quantitative values of SWE and SMI with B-mode US improved the diagnostic performance in differentiating between benign and malignant breast lesions.

• Imaging Science in Dentistry
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• v.49 no.4
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• pp.301-306
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• 2019

Purpose: This report presents a procedure for performing power Doppler ultrasound-guided sialography using the phenomenon of increased blood flow and illustrates its application to practical patient cases. Materials and Methods: The salivary gland was scanned using ultrasound equipment (GE LOGIQ5 Expert^® device; GE Medical Systems, Milwaukee, WI, USA) to identify pathological findings related to the patient's chief complaint. To identify the orifice of the main duct, it should be cannulated using a lacrimal dilator. After inserting the catheter into the cannulated main duct, the position of the catheter within the duct was confirmed by ultrasound. A contrast agent was injected until the patient felt fullness, and ultrasound (B-mode) was used to confirm whether the contrast agent filled the main canal and secondary and tertiary ducts. Then, power Doppler ultrasound was performed to determine whether the salivary gland had increased blood flow. Results: In 2 cases in this report, a power Doppler ultrasound scan showed a significant increase in blood flow after contrast medium injection, which was not observed on a preoperative scan. Conclusion: Power Doppler ultrasound was found to be a simple, safe, and effective tool for real-time sialography monitoring.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.6
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• pp.521-537
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• 2000

Ultrasonic imaging is the most widely used modality among modern imaging device for medical diagnosis and the system performance has been improved dramatically since early 90's due to the rapid advances in DSP performance and VLSI technology that made it possible to employ more sophisticated algorithms. This paper describes "main stream" digital signal processing functions along with the associated implementation considerations in modern medical ultrasound imaging systems. Topics covered include signal processing methods for resolution improvement, ultrasound imaging system architectures, roles and necessity of the applications of DSP and VLSI technology in the development of the medical ultrasound imaging systems, and array signal processing techniques for ultrasound focusing.

• Journal of radiological science and technology
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• v.40 no.2
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• pp.213-218
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• 2017

Recently, as the number of high-risk pregnancies increases, the use of new techniques such as Doppler, which have higher acoustic power than in the past, has been increasingly used in prenatal diagnosis and guidelines have been set up by various organizations to prevent excessive exposure. Therefore, in this study, we tried to investigate the temperature change of the body surface for each test mode according to the long time ultrasound examination and to examine the exposure time which is not influenced by the thermal effect. B mode, C mode, and PD mode according to time, and the temperature difference between exposed and unexposed sites were compared. As a result, the B mode showed a significant difference in the temperature change from 10 minutes, 50 minutes after exposed, 20 minutes from the C mode, and 30 minutes from the PD mode (p<0.01). In all three modes, the temperature difference was different (p<0.000), and PD mode was the most sensitive to temperature change. Also, it was found that the temperature rise time was shortened with the increase of the ultrasonic exposure time. Therefore, it is recommended that ultrasonography to observe the embryo or fetus should be used only for diagnostic purposes, avoiding excessive test time.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.4
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• pp.457-463
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• 2014

Ultrasound measurements of backfat thickness (UBF), longissimus muscle area (ULMA) and marbling score (UMS) and carcass measurements of carcass weight (CW), backfat thickness (BF), longissimus muscle area (LMA), and marbling score (MS) on 7,044 Hanwoo steers were analyzed to estimate genetic parameters. Data from Hanwoo steers that were raised, finished in Hoengseong-gun, Gangwon-do (province) and shipped to slaughter houses during the period from October 2010 to April 2013 were evaluated. Ultrasound measurements were taken at approximately three months before slaughter by an experienced operator using a B-mode real-time ultrasound device (HS-2000, FHK Co. Ltd., Tokyo, Japan) with a 3.5 MHz linear probe. Ultrasound scanning was on the left side between 13th rib and the first lumbar vertebrae. All slaughtering processes and carcass evaluations were performed in accordance with the guidelines of beef grading system of Korea. To estimate genetic parameters, multiple trait animal models were applied. Fixed effects included in the models were: the effects of farm, contemporary group effects (year-season at the time of ultrasound scanning in the models for UBF, ULMA, and UMS, and year-season at slaughter in the models for CW, BF, LMA, and MS), the effects of ultrasound technicians as class variables and the effects of the age in days at ultrasound scanning or at slaughtering as linear covariates, respectively for ultrasound and carcass measures. Heritability estimates obtained from our analyses were 0.37 for UBF, 0.13 for ULMA, 0.27 for UMS, 0.44 for CW, 0.33 for BF, 0.36 for LMA and 0.54 MS, respectively. Genetic correlations were strongly positive between corresponding traits of ultrasound and carcass measures. Genetic correlation coefficient between UBF and BF estimate was 0.938, between ULMA and LMA was 0.767 and between UMS and MS was 0.925. These results suggest that ultrasound measurement traits are genetically similar to carcass measurement traits.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1491-1495
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• 2004

In this paper, resonant ultrasound spectroscopy(RUS) was used to determine the natural frequency of a spherical and a aspherical lens. The objective of the paper is to evaluate defect and shape error by using nondestructive evaluation method with Resonant Ultrasound Spectroscopy(RUS). The principle of RUS is that the mechanical resonant frequency of the materials depends on density, and the coefficient of elasticity. We evaluated existence of flaws through comparison with resonant frequency of a spherical and a aspherical lens. The spherical glass lenses were made of BK-7 glass, one's diameter in 2mm and 5mm. The polished spherical glass lenses had no deflection or a deflection below 2.0${\mu}{\textrm}{m}$. Also, The aspherical lens were made of same material and ones diameter in 7mm and thickness in 3.4mm. In the experiment, we were performed to investigate relationship between frequency measuring parameter($\beta$) and mass of each specimens. The difference between resonant frequency and mode of aspherical glass lens which has no defect was distinguished from aspherical glass lens which has some defects.

• The Journal of the Acoustical Society of Korea
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• v.31 no.8
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• pp.580-589
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• 2012

In this paper, we studied on Doppler gap-filling algorithms suitable for a portable or low-cost medical ultrasound imaging system, and as a result, found out algorithms based on mirroring or autoregressive model. Moreover, controlling the computational demand in the proper range, we improved the performances of these algorithms by solving their problems. Effectiveness of these modified algorithms is verified by computer simulations and experiments which used artificially generated Doppler signals and Doppler data acquired from human body through an actual ultrasound system.

• Journal of Biomedical Engineering Research
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• v.30 no.3
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• pp.233-240
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• 2009

Using a spatial compound imaging technique in a medical ultrasound imaging system, the average speed of sound in a medium of interest is measured, and imaging of its distribution is implemented. When the brightness reaches the highest level in an ultrasonic image obtained as the speed of sound used in focusing is varied, it turns out that the focusing has been accomplished satisfactorily and that the speed of sound which has been adopted becomes the sought-after average speed of sound. Because spatial compound imaging provides many different views of the same object, the adverse effect of erroneous speed-of-sound estimation tends to be more severe in compound imaging than in plain B-mode imaging. Thus, in compound imaging, the average speed of sound even in the case of speckled images can be accurately estimated by observing the brightness change due to different speeds of sound employed. Using this new method that offers spatial diversity, we can construct an image of the speed of sound distribution in a phantom embedded with a 10-mm diameter plastic cylinder whose speed of sound is different from that of the background. The speed of sound in the cylinder is found to be different from that of the surrounding medium.

• Journal of radiological science and technology
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• v.41 no.1
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• pp.53-60
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• 2018

The purpose of this study was investigating the effect of 3D printing technology that changes the speed of sound (SOS) and the broadband ultrasound attenuation (BUA) by controlling the density of the media phantom. We used 3D printers which called additive manufacturing (AM) by using material with polylactic acid (PLA). The inside of the medium phantom was filled crossly with 100%, 90%, 80%, 70%, 60%, and 50% of the material. The ultrasonic instrument measured the SOS and the BUA using a 0.55 MHz ultrasound output in opposing mode with a pair of transducers. As a result, the density of the medium phantoms with the SOS showed very high correlation (r = 0.944), but the SOS showed very low correlation (r = 0.500). It is expecting that the manufacturing and measurement method of the medium phantom using 3D printing technology will be used as basic data for ultrasonic bone mineral density.

• Korean Journal of Ecology and Environment
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• v.40 no.2
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• pp.244-253
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• 2007

In this study, mortality, body wet weight, health assessment, and short-term behavioral mode were observed to determine the effects of ultrasound on the ecological response of the carp Cyprinus carpio. Mortality in the treatments was less than 5% during ultrasound exposure (31 dB re 1 ${\mu}Pa$, $14{\sim}15$ kHz) and there were no significant differences among the replicates (P>0.05). The treatments, based on mean wet weight, exhibited greater effect than the controls, but the magnitude of the differences was not large. Skins and tail fins of some test animals exposed to the controls and intensive treatment groups had light injury such as hemorrhaging, whereas, damages in other organs such as eyes, other fins, parasites, thymus, and gills were not observed (P>0.05). Sudden stimuli in low intensity at a short distance caused a directional avoidance of the fish from the sound. However, the carp exposed to ultrasound at the large scale field was not observed clear behavior changes. Overall results suggest that fish exposed to the low-intensity ultrasound had no serious stress during the tests.