• 대한의용생체공학회:의공학회지
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• 제36권5호
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• pp.150-154
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• 2015

Long time ultrasound scan can cause a temperature rise in human tissue and affect the physical body. This is closely connected with patients' safety. So many researchers have been studied on this matter with animals such as mammals and experimental rat, because diagnostic ultrasound has been used many types of human organ to find disease. Therefore, this study is tested on bean sprouts to search how far the tissue temperature changes because of the excessive scanning consequence from ultrasound diagnosis and frequent number of ultrasonic scanning and how much affect their growth. The United States and several European countries have restrictions for number of scanning, while South Korea does not have any limitation for using ultrasound diagnosis. Comparison was that how different condition affect its' growing. The testing group is like many pregnancy moms to have 50 minutes in B-mode and color doppler mode by linear, convex and sector probe every day for a week and the other is to scan only once during the testing period. As a result, it was confirmed that there was a significant growing difference on frequent ultrasonic scanning group compared to normal one. So the final conclusion is that there needs to have a significant limitation of ultrasound scan time and a number of inspection when having for diagnostic ultrasound and recommendation like USA and a few European countries.

• The Journal of the Acoustical Society of Korea
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• 제25권4E호
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• pp.159-165
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• 2006

Human, horse and rat bloods in a cylindrical chamber where flow was controlled by a stirring magnet were used for studying red blood cell aggregation. Ultrasound backscattered powers from blood were obtained from the backscattered signals measured by a 5 MHz focused transducer in a pulse-echo setup. The experimental results showed the differences in red blood cell (RBC) aggregation tendency among the three mammalian species with an order of horse > human > rat. The ultrasound backscattered power decreased with stirring speed in human and horse blood, but no variations were observed in rat blood. Sudden flow stoppage led to the slow increase of the backscattered power for human and horse blood. There was no self-aggregation tendency in rat blood. The enveloped echo images showed the spatial and temporal variations of RBC aggregations in the cylindrical chamber. These observations from the different mammalian species may give a better understanding of the mechanism of RBC aggregation.

• 대한의용생체공학회:의공학회지
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• 제29권4호
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• pp.302-306
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• 2008

Plastic hardener and softener based ultrasound phantoms were made in various constitutions and their acoustic properties were measured. Speed of sound is approximately $1.4\;mm/{\mu}sec$ in all the phantoms, which is about 7% less than that of in soft tissue. Attenuation coefficient is strongly dependent on the ratio between hardener and softener. In order to achieve the tissue level attenuation (0.5 dB/cm/MHz), 60% of hardener or less is required. The synthesized phantoms can be preserved for more than 6 months without structural degradation.

• 대한의생명과학회지
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• 제25권4호
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• pp.381-389
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• 2019

The physiological function test is the only patient contact area in the field of clinical laboratory. We need to recruit and encourage the experts due to requiring the expertise and long time for examination. However, there is currently no rule for estimating optimal workforce in the field of physiological function tests. The purpose of this study is to establish the basis of the studies for mid- to long-long term job creation in the field of ultrasound by evaluating the number of appropriate tests and appropriate workforce. We calculated the quantitative and qualitative workload for the number of appropriate tests and appropriate workforce using online questionnaire. All statistical analyses were performed using SPSS version 18.0 (SPSS Inc., Chicago, IL, USA). A total of 216 respondents were 48 (22.2%) male and 168 (77.8%) female. A total of 157 laboratories were 62 (39.5%) for echocardiography, 91 (58.0%) for the transcranial Doppler (TCD) and 4 (5.7%) for the carotid ultrasound. The mean number of appropriate tests was 10 ± 2 in the echocardiography, 9 ± 2 in TCD and 11 ± 2 in the carotid ultrasound. In addition, the number of laboratories required to recruit employees for appropriate workforce was 19 in echocardiography, 18 in TCD, and 0 in carotid ultrasound. The number of hospital required to recruit workforce were 7 primary hospitals, 22 secondary hospitals, 7 third hospitals. This study can be used as an important data as the first study at present time when the data on the workforce status and work environment of the ultrasonic laboratories is insufficient. Based on the quantitative and qualitative workloads, the number of appropriate tests and appropriate workforce can support mid- to long-long term job creation in the field of ultrasound.

• 한국음향학회지
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• 제42권5호
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• pp.429-440
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• 2023

이 연구는 초음파 광학 영상 기반의 다중 모달 영상 기술에 대한 최신 연구 동향과 응용 가능성에 대해 조사하였다. 초음파 영상은 실시간 영상 기능을 가지고 있으며 인체에 상대적으로 안전한 특성으로 인해 의료 분야에서 다양한 질병의 진단에 사용되고 있다. 그러나 초음파 영상은 해상도가 낮은 한계가 있어 진단 정확도를 향상시키기 위해 다른 광학 영상과의 결합을 통한 다중 모달 영상 기술 개발 연구가 진행되고 있다. 특히 초음파 광학 영상 기반의 다중 모달 영상 기술은 각각의 영상 기법의 장점을 극대화하고 단점을 보완함으로써 질병 진단 정확도를 향상시킬 수 있는 수단으로 사용되고 있다. 이러한 기술은 초음파의 실시간 영상 기능과 광간섭 단층 영상 융합 기술, 초음파 광음향 다중 모달 영상 기술, 초음파 형광 다중 모달 영상 기술, 초음파 형광 시정수 다중 모달 영상 기술 및 초음파 분광 다중 모달 영상 기술 등 다양한 형태로 제안되고 있다. 본 연구에서는 이러한 초음파 광학 영상 기반의 다중 모달 영상 기술의 최신 연구 동향을 소개하고, 의학 및 바이오 분야에서의 응용 가능성을 조사하였다. 이를 통해 초음파와 광학 기술의 융합이 어떻게 진행되고 있는지에 대한 통찰력을 제공하고, 의료 분야에서의 진단 정확도 향상을 위한 새로운 접근 방식에 대한 기반을 마련하였다.

• The Journal of the Acoustical Society of Korea
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• 제29권1E호
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• pp.28-37
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• 2010

This article reviews recent developments in the emerging field of cellular-level biomedical ultrasonics with the specific focus on the mechanics of ultrasound-cell interaction. Due to the nature of the field at its relative infancy, the review poses more questions than it provides answers. Discussed are topics such as the basic structure of a biological cell, the origin of cell's elasticity, a theoretical framework for ultrasound-cell interaction, and shape deformation of cells and its measurement, Some interesting problems for future study are proposed.

• 한국방사선학회논문지
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• 제6권3호
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• pp.201-206
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• 2012

진단적 초음파가 태아에 미치는 영향에 대하여는 대부분의 연구결과, 심각한 영향을 미칠 가능성이 매우 낮다고 보고되고 있으나, 장시간의 과도한 조사는 초음파가 인체조직에 온도 상승이나 물리적인 영향을 줄 수 있어 초음파 검사시간에 따라 허벅지의 온도 변화를 조사하여 태아 초음파 검사 시 영향이 없는 시간을 알아보았다. 그 결과 초음파 검사 전보다 40분 안에는 온도가 떨어졌고 50분에는 허벅지의 온도가 검사 전보다 $1^{\circ}C$이상 올라가는 것을 확인하였다. 그러므로 40분 안에 초음파 검사를 한다면 안전한 것으로 추론해 본다.

• The Journal of the Acoustical Society of Korea
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• 제28권1E호
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• pp.1-8
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• 2009

Primary radiation force on ultrasound contrast agents (UCA) in a propagating and standing acoustic field was explored. A specific ultrasound contrast agent $Albunex^{(R)}$ and $Optison^{(R)}$ were chosen for simulation. The model was developed based on a shelled bubble model proposed by Church. The numerical simulation suggests that bubble translational motion is more significant in therapeutic ultrasound due to higher intensity and long pulse duration. Even a single cycle of a propagating wave of 4 MPa at 1 MHz can cause a bubble translational motion of greater than $1{\mu}m$ which is approximately one tenth of capillary. Hence, UCA characteristics can be significantly changed in therapeutic ultrasound without rapid bubble collapses.

• Clinical Endoscopy
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• 제57권3호
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• pp.332-334
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• 2024

• 대한의용생체공학회:의공학회지
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• 제42권3호
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• pp.100-106
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• 2021

Measuring Intima-media thickness (IMT) with ultrasound images can help early detection of coronary artery disease. As a result, numerous machine learning studies have been conducted to measure IMT. However, most of these studies require several steps of pre-treatment to extract the boundary, and some require manual intervention, so they are not suitable for on-site treatment in urgent situations. in this paper, we propose to use deep learning networks U-Net, Attention U-Net, and Pretrained U-Net to automatically segment the intima-media complex. This study also applied the HE, HS, and CLAHE preprocessing technique to wireless portable ultrasound diagnostic device images. As a result, The average dice coefficient of HE applied Models is 71% and CLAHE applied Models is 70%, while the HS applied Models have improved as 72% dice coefficient. Among them, Pretrained U-Net showed the highest performance with an average of 74%. When comparing this with the mean value of IMT measured by Conventional wired ultrasound equipment, the highest correlation coefficient value was shown in the HS applied pretrained U-Net.