• Clinical Pain
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• 제20권2호
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• pp.86-92
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• 2021

Ultrasound imaging in clinical practice is one of the widely used diagnostic methods because there is no radiation risk, more cost- effective compared to MRI or CT, and possible to perform an intervention through fast real-time imaging. In order to increase the diagnostic value, the studies of contrast-enhanced ultrasound (CEUS) using an ultrasound contrast agent have been actively conducted since about 50 years ago and are being used clinically in vascularity and microcirculation of internal organs. Although ultrasound is actively used for the diagnosis and treatment of various diseases in musculoskeletal disorders, there are some limitations in diagnosing mild or small lesions, inflammatory reactions, or abnormalities at the molecular level. In this review, the principles, types, and research, and clinical applications of ultrasound contrast agents have been summarized and introduced. If we understand the characteristics of the ultrasound contrast agents and anatomical knowledge, as well as molecular changes, the ultrasound contrast agents are widely applied in musculoskeletal disorders and have tremendous potential for diagnosis and treatment.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.357-358
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• 2007

Contrast enhancement in the field of ultrasound imaging contributes to improve the accuracy of medical diagnosis by enhancing the visibility of ultrasound images. This paper proposes a contrast enhancement method that improves the contrast of ultrasound images both globally and locally by fusing global and adaptive contrast enhancement methods. Experimental results show that our approach yields more competitive results than the existing global and adaptive contrast enhancement methods in enhancing the visibility of ultrasound images.

• 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.

• Asian Pacific Journal of Cancer Prevention
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• 제13권2호
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• pp.493-497
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• 2012

This study was conducted to retrospectively evaluate the pattern of contrast enhancement with SonoVue on gray-scale ultrasonography of hepatic angiomyolipoma (HAML). Imaging features of 33 pathologically proven HAML lesions in 33 patients who underwent baseline ultrasound and contrast-enhanced ultrasonography (CEUS) were assessed retrospectively. All lesions were enhanced in the arterial phase and showed whole-tumor filling in. Thirty-two of 33 (97%) lesions showed early positive enhancement in the arterial phase. Twenty-three of these exhibited isoechoic or hyperechoic features in the portal phase. HAML demonstrate characteristic manifestations with SonoVue-enhanced real-time gray-scale ultrasonography.

• 대한방사선기술학회지:방사선기술과학
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• 제29권2호
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• pp.63-69
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• 2006

초음파 영상의 질은 진단에 많은 영향을 끼친다. 양질의 영상이 항상 일정하게 유지되기 위해서는 QA(Quality Assurance) 프로그램을 가지고 주기적인 관리가 이루어져야 할 것이다. 본 논문은 임상에서의 QA 상황을 파악하는 첫 번째 단계로 실제 병원의 초음파 영상의 질을 살펴보고자 하였다. 이를 위해 인간의 생체등가물질로 된 팬텀을 이용하여 정상 환자를 스캔할 때와 같은 기준 값에서 가상의 낭포 및 고반사 신호의 구조물들이 몇 개가 보이는지 convex probe와 linear probe를 측정하여 비교하였다. convex probe에서는 정상 간과 비슷한 0.5 dB에서 vertical group, cystic masses, high contrast masses에서는 대부분 잘 보였으며 지방간과 비슷한 조건인 0.7 dB에서는 vertical group이 중간레벨에서, cystic masses와 high contrast masses에서는 대체로 모두 잘 보였다. linear probe에서의 vertical group은 0.5 dB에서 중간레벨만 잘 보였고 cystic masses와 high contrast masses는 두 개에서 네 개 보이는 것들이 고루 분포되었으나 하나도 보이는 않는 경우가 11건수나 되었다. 0.7 dB에서는 vertical group이 6개 이하가 보이는 것이 대부분 이었고 cystic masses와 high contrast masses에서도 두개에서 네 개 보이는 것들이 고루 분포되었고 하나도 보이는 않는 경우도 40건 있었다. 이로서 지방간과 같은 조건하에서는 linear probe의 영상의 질이 대체로 좋지 않으므로 기준 설정 및 물리적인 조건들을 검사 시에 잘 조정하거나 probe의 교체가 필요하다고 판단된다. 많은 병원에서 초음파 장비를 잘 관리하고 있다고 하지만, 영상의 질은 아직도 미흡한 것을 알 수 있다. 초음파 장비의 설치에서부터 영상의 질을 평가하고 지속적이고 정기적인 관리와 평가가 이루어질 수 있는 프로그램이 필요하겠다.

• 소음진동
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• 제10권5호
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• pp.743-759
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• 2000

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7449-7452
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• 2014

Background: The purpose of this study was to investigate the correlation of contrast-enhanced ultrasonographic (CEUS) features with microvessel density (MVD) in papillary thyroid carcinomas (PTCs). Materials and Methods: Contrast-enhanced ultrasonography (CEUS) was performed in 62 patients (17 men and 45 women) with PTC. Tomtec software was applied to analyze the time intensity curve of CEUS. Immunohistochemistry was performed to evaluate the level of MVD in papillary thyroid carcinoma. Then the relationship between quantitative feature and the level of MVD was analyzed using SPSS 16.0 software. Results: The mean peak intensity of PTC tissues was lower than that of peripheral thyroid parenchyma ($61.9{\pm}11.8%$ vs 100%, p<0.05). The MVDs of CD34 and CD31 antibodies staining were $38.0{\pm}6.1$ and $37.9{\pm}5.1$ respectively in 62 PTC samples. A significantly positive correlation was observed between peak intensity and MVD in PTC tissues ($P_{CD34}$<0.01, $r_{CD34}$=0.838, $P_{CD31}$<0.01, $r_{CD31}$=0.837). Conclusions: The peak intensity in CEUS could reflect the MVD in PTC tissues. Therefore, quantification of CEUS seems to be helpful for assessment of MVD in PTC tissues.

• 대한기계학회논문집B
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• 제28권12호
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• pp.1528-1534
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• 2004

The combination of ultrasound echo images with digital particle image velocimetry (DPIV) methods has resulted in a two-dimensional, two-component velocity field measurement technique appropriate for opaque flow conditions including blood flow in clinical applications. Advanced PIV processing algorithms including an iterative scheme and window offsetting were used to increase spatial resolution. The optimum concentration of the ultrasound contrast agent used for seeding was explored. Velocity validation tests in fully developed laminar pipe flow result of echo PIV showed good agreement with both optical PIV measurements and the known analytic solution based on a volume flow measurement.

• 한국정보통신학회논문지
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• 제17권9호
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• pp.2206-2212
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• 2013

본 논문은 Fuzzy Contrast Enhancement 기법과 FCM을 이용하여 대비를 개선한 후, Fuzzy Contrast Enhancement를 간과 신장의 초음파 영상에 적용하여 지방간 농도 수치를 분류하는 방법을 제시한다. 간, 신장 영역을 촬영한 초음파 영상에서 촬영 정보나 눈금자 등과 같이 필요 없는 부분을 잡음으로 간주하여, 제거한 ROI 영상을 추출하고, Fuzzy Contrast Enhancement 알고리즘을 이용하여 명암 대비를 강조한다. Fuzzy Contrast Enhancement 기법이 적용된 간, 신장 영역 영상에서 평균 이진화를 적용한 후, 평균 이진화를 적용한 영상에 Blob 알고리즘을 적용하여 간, 신장 실질 영역의 ROI 영상을 추출한다. 추출한 간 영역과 신장영역의 ROI 영상을 FCM을 이용하여, 10개의 명암도 Level로 각 각 분류한 후, 분류된 간, 신장 실질 영역의 명암도 Level 중 많이 분포된 명암도 Level을 기준으로 간, 신장 실질 영역의 대표 명암도를 추출한다. 제안된 방법을 간, 신장 영역을 촬영한 초음파 영상에 적용하여 간의 지방도를 분류한 결과, 영상의학과 전문의의 판독과 일치하여 향후 지방간의 진단에 효과적으로 적용할 수 있는 방법이 될 수 있을 것으로 사료된다.

• Korean Journal of Radiology
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• 제22권5호
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• pp.677-687
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• 2021

Microvascular ultrasound (US) techniques are advanced Doppler techniques that provide high sensitivity and spatial resolution for detailed visualization of low-flow vessels. Microvascular US imaging can be applied to breast lesion evaluation with or without US contrast agents. Microvascular US imaging without a contrast agent uses a sophisticated wall filtering system to selectively obtain low-flow Doppler signals from overlapped artifacts. Microvascular US imaging with second-generation contrast agents amplifies flow signals and makes them last longer, which facilitates hemodynamic evaluation of breast lesions. In this review article, we will introduce various microvascular US techniques, explain their clinical applications in breast cancer diagnosis and radiologic-histopathologic correlation, and provide a summary of a recent radiogenomic study using microvascular US.