• 대한영상의학회지
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• 제81권1호
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• pp.157-165
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• 2020

목적 S-Shearwave를 이용하여 유방 병변을 감별하는데 있어 최적의 cut-off 값과 종괴 내 위치를 알아보고 진단적 가치를 평가하고자 한다. 대상과 방법 연구 기간 동안 197명의 여성에서 225개의 유방 병변을 평가하였다. S-Shearwave 값은 초음파 기기에서 자동적으로 생성된 사각형의 region-of-interest로 측정하였다. 병변 내 서로 다른 네 군데에서 각각 세 번 측정하였으며 세 개의 중위 값 중 최대 값을 이용해 각각의 위치에서 최적의 cut-off 값을 계산하였다. 진단적 가치는 area under the receiving operator characteristics curve (이하 AUC)를 통해 평가하였다. 결과 총 225개의 유방 병변 중 156개(69.3%)는 양성, 69개(30.7%)는 악성이었다. 평균 SShearwave 값은 악성 병변이 양성 병변에 비해 유의미하게 높았다(108.0 ± 70.0 kPa vs. 43.4 ± 38.3 kPa, p < 0.001). 하지만 병변 내 위치에 따른 값의 유의미한 차이는 없었다. Cut-off 값을 41.9 kPa로 사용했을 때, 민감도 85.7%, 특이도 63.9%, 정확도 70.7%, 양성예측도 51.7% 및 음성예측도 90.8%였다. 초음파와 S-Shearwave 간의 AUC는 유의미한 차이를 보이지 않았다(p = 0.179). 결론 S-Shearwave는 유방 병변의 감별진단을 하는데 grayscale 초음파에 필적하는 진단적 가치를 가진다.

• Investigative Magnetic Resonance Imaging
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• 제11권1호
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• pp.10-19
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• 2007

기존 MRI, 즉 T1 강조-, T2 강조-, 확산-, 관류-, 기능적-, 등의 영상법은 조직의 물리적 파라미터 그리고 기능적 특성을 알려주는 역할을 한다. 본 종설에서는 최근 관심이 높아지고 있는 영상기법의 하나로 MRE (Magnetic Resonance Elastography, 자기공명탄성법)를 소개하고자 한다. MRE는 기존의 물리적, 기능적 측정을 벗어나 조직의 기계적 특성에 관한 정보를 제공해준다는 면에서 MRI를 이용한 새로운 modality로서의 가능성을 시사해 준다. 예로부터 진단의 가장 기초적인 방법중 하나로서 촉진을 이용하여 조직의 경도를 가늠하여 왔다. MRE는 조직의 경도를 MRI를 이용하여 객관적으로 수치화해준다. MRE 임상실험을 성공적으로 수행하기 위해서는 몇 가지 하드웨어와 소프트웨어(트랜스듀서, 펄스대열, 영상처리 알고리즘)가 구비되어야 한다. 트랜스듀서는 인체에 진동을 전달해주는 부분으로서 MRE 응용을 가능하게 하는 핵심적인 역할을 한다. 따라서 MRI 시스템의 자기장과 인체의 골격, 피부와 트랜스듀서 접촉면의 압력, 마찰을 고려하여 제작하여야 한다. 트랜스듀서를 통해서 인체 내부에 진동이 전달되고 있으면 최적의 영상을 얻기 위하여 고려되어야 할 사항이 펄스대열을 조정하는 것이다. 마지막으로 여러 가지 물질에 대한 가정(등방성, 균질성, 비압축성)하에서 영상처리 알고리즘은 파동방정식(Helmholtz equation)으로 표현되며 이로부터 탄성도(Elasticity or Modulus)를 구할 수 있다. 본 종설에서는 이에 대한 리뷰 및 MRE를 이용한 응용분야에 대하여 살펴본다.

• 비파괴검사학회지
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• 제29권4호
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• pp.293-298
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• 2009

본 연구에서는 나노 표면층의 특성 평가를 위해 원자현미경에 초음파 특성을 결합하여 초음파 원자 현미경을 개발하였다. 초음파 원자 현미경은 기존의 나노 표면층에 대한 토포그래프 이미지뿐만 아니라 국부적인 이종부분으로 이루어진 표면에서의 물리적 특성차이에 의한 표면의 탄성 특성 이미지를 얻을 수 있다. 본 연구에서는 프로토타입의 UAFM 장치를 구성하고 이를 몇몇 응용분야에 적용하였다. 구축한 프로토타입의 UAFM 시스템을 이용하여 증착 실리콘 박막층과 냉간 압조용 강의 구상화 그리고 탄소 섬유 강화 복합재료의 표면에 대한 탄성 이미지를 성공적으로 얻을 수 있었다.

• Imaging Science in Dentistry
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• 제48권3호
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• pp.161-165
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• 2018

Purpose: To evaluate the usefulness of shear wave elastography in the diagnosis of oral and maxillofacial diseases. Materials and Methods: Ten patients with oral and maxillofacial diseases and 28 volunteers drawn from our student doctors were examined by shear wave elastography with a 14-MHz linear transducer using an Aplio 300 apparatus (Canon Medical Systems, Otawara, Japan). A statistical analysis of the shear elastic modulus(kPa) of healthy tissue (the sublingual gland, submandibular gland, anterior belly of the digastric muscle, and geniohyoid muscle) in the 28 volunteers was performed using 1-way repeated measures analysis of variance with the Tukey honest significant difference test. The maximum shear elastic modulus(kPa) of 8 patients with squamous cell carcinoma (SCC) and 2 patients with benign lesions was evaluated with the Mann-Whitney U test. The analysis used a 5% significance level. Results: The mean shear elastic modulus of the sublingual gland ($9.4{\pm}3.7kPa$) was lower than that of the geniohyoid muscle ($19.2{\pm}9.2kPa$, P=.000) and the anterior belly of the digastric muscle ($15.3{\pm}6.1kPa$, P=.004). The maximum shear elastic modulus of the SCCs($109.6{\pm}14.4kPa$) was higher than that of the benign lesions($46.4{\pm}26.8kPa$, P=.044). Conclusion: Our results demonstrated the usefulness of shear wave elastography in the diagnosis of oral and maxillofacial diseases. Shear wave elastography has the potential to be an effective technique for the objective and quantitative diagnosis of oral and maxillofacial diseases.

• Journal of Acupuncture Research
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• 제31권3호
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• pp.7-18
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• 2014

Objectives : The purpose of this study is to find parameters to compare the effects of Sa-Am acupuncture with large intestine tonifying and sedating on radial pulse in healthy subjects. Methods : Sixty healthy subjects participated in this study, divided into large intestine tonifying acupuncture group, large intestine sedating acupuncture group and control group. Radial pulse was measured by 3 dimensional pulse imaging system(DMP-3000) before, right after, 30 minutes after and 60 minutes after acupuncture at Cun, Guan, and Chi in the acupuncture group and in the control group at the same time points. Results : 1. Angle of main peak and magnitude of fourier component significantly changed by integrated analysis of Cun, Guan and Chi. 2. Amplitude of H1, Pulse Power volume / min, elasticity, AIx / HR, Frequency and magnitude of fourier component significantly changed by analysis of Cun, Guan, and Chi. Conclusions : The effect of Sa-Am acupuncture with large intestine tonifying and sedating in healthy human may be observed on time, amplitude, pulse area, augmentation index and fourier components parameters. The parameters analysed in this study may be used to differentiate the effects between Sa-Am acupuncture with large intestine tonifying and sedating on radial pulse. Further studies on the effects of Sa-Am acupuncture using radial pulse are needed.

• Journal of Acupuncture Research
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• 제30권4호
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• pp.1-14
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• 2013

Objectives : The purpose of this study is to investigate the effects of Sa-Am spleen-tonifying acupuncture on radial pulse in healthy human subjects. Methods : Forty healthy human subjects participated in this study, divided into acupuncture group and control group. Radial pulse was measured by 3 dimensional pulse imaging system(DMP-3000) before, right after, 30 minutes after and 60 minutes after acupuncture in the acupuncture group. The subjects in the control group didn't received acupuncture but took a rest and then the radial pulse was measured at the same time points as the acupuncture group. The parameters were analyzed by gender, measuring location, and measuring time point. However the time related parameters exceptionally were analyzed without distinction of measuring location. Results : 1. T, variance of period, T2/T, T4/T, (T-T4)/T, T4/(T-T4), and W significantly changed after acupuncture. 2. Pressure, amplitude of H1, amplitude of H2, Amplitude of H4 and pulse energy significantly changed after acupuncture. 3. Pulse area, systolic pulse area and diastolic pulse area significantly changed after acupuncture. 4. Elasticity, AIx and AIx/HR significantly changed after acupuncture. Conclusions : The effect of Sa-Am spleen-tonifying acupuncture in healthy human may be observed on time, amplitude, pulse area and augmentation index. Further studies on the effects of Sa-Am acupuncture using radial pulse are needed.

• Imaging Science in Dentistry
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• 제48권1호
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• pp.45-49
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• 2018

Purpose: The aim of this study was to evaluate the quantitative strain elastography of tongue carcinoma using intraoral ultrasonography. Materials and Methods: Two patients with squamous cell carcinoma (SCC) who underwent quantitative strain elastography for the diagnosis of tongue lesions using intraoral ultrasonography were included in this prospective study. Strain elastography was performed using a linear 14 MHz transducer (Aplio 300; Canon Medical Systems, Otawara, Japan). Manual light compression and decompression of the tongue by the transducer was performed to achieve optimal and consistent color coding. The variation in tissue strain over time caused by the compression exerted using the probe was displayed as a strain graph. The integrated strain elastography software allowed the operator to place circular regions of interest (ROIs) of various diameters within the elastography window, and automatically displayed quantitative strain (%) for each ROI. Quantitative indices of the strain (%) were measured for normal tissues and lesions in the tongue. Results: The average strain of normal tissue and tongue SCC in a 50-year-old man was 1.468% and 0.000%, respectively. The average strain of normal tissue and tongue SCC in a 59-year-old man was 1.007% and 0.000%, respectively. Conclusion: We investigated the quantitative strain elastography of tongue carcinoma using intraoral ultrasonography. Strain elastography using intraoral ultrasonography is a promising technique for characterizing and differentiating normal tissues and SCC in the tongue.

• 한국가시화정보학회지
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• 제19권3호
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• pp.15-21
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• 2021

In this study, we investigated the dynamics of a droplet impacting rough hydrophobic surfaces through high-speed imaging. Micrometer-sized structures with grooves and pillars were fabricated on smooth Polydimethylsiloxane (PDMS) surfaces by laser ablation. We used Newtonian and non-Newtonian liquid droplets to study the drop impact dynamics. De-ionized water and aqueous glycerin solutions were used for the Newtonian liquid droplet. The solutions of xanthan gum in water were prepared to provide elastic property to the Newtonian droplet. We found that the orientation of the surface structures affected the maximal spreading diameter of the droplet due to the degree of slippage. During the droplet retraction, the dynamic receding contact angles were measured to be around 90° or less. It resulted in the formation of the micro-capillary bridges between the receding droplet and the surface structures. Then, the rupture of the capillary bridge led to the formation of micrometer-sized droplets on top of the surface structures. The size of the microdroplets was found to increase with increasing the impacting velocity and viscosity of the Newtonian liquid droplets. However, the size of the isolated microdroplets decreased with enhancing the elasticity of the droplets, and the size of the non-Newtonian microdroplets was not affected by the impacting velocity.

• 대한영상의학회지
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• 제84권6호
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• pp.1397-1402
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• 2023

결절성 근막염은 양성 섬유모세포 증식으로 유방에는 드물게 보고된다. 저자들은 악성 영상 소견을 보인 55세 여자 환자의 증례를 보고한다. 유방촬영술에서 오른쪽 유방에 유방조직과 비슷한 밀도를 보인 부분적으로 경계가 불명확한 결절이 보였고 인공지능 점수는 75%였다. 초음파에서 미세 소엽상 경계, 주변부 고에코를 가진 타원형의 저에코 결절이 보였고 증가된 혈류와 부드러운 탄성도를 보였다. 조직검사와 수술 후 결절성 근막염으로 진단되었다. 결절성 근막염은 유방에서 드물지만, 악성과 비슷하게 보일 수 있다. 따라서 불필요한 중재시술을 막기 위해 감별진단으로 고려되어야 한다.

• Clinics in Shoulder and Elbow
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• 제17권3호
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• pp.107-113
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• 2014

Background: Sonoelastography (SE) is a new technique that can assess differences in tissue stiffness, the purpose of this study was to evaluate the ability of SE to assess the long head of biceps tendon alteration. Methods: Forty shoulders of 36 consecutively registered patients with clinical symptoms and conventional ultrasonography findings of biceps tendinitis or tendinosis, and 40 asymptomatic shoulders of 20 healthy volunteers were assessed with SE. Transverse and longitudinal images of long head of biceps tendon were obtained using SE. SE images were performed by one orthopedic surgeon and evaluated by two orthopedic surgeons using an experimentally proven color grading system. Results: The transverse images of SE showed a sensitivity of 87.5%, a specificity of 95.0% and a accuracy of 91.3%, the longitudinal images of SE showed a sensitivity of 92.5%, a specificity of 90.0% and a accuracy of 91.3%. Inter-observer reliability of SE was in 'almost perfect agreement' with a weighted kappa coefficient of 0.83. Conclusions: SE is valuable in the detection of the intratendinous and peritendinous alterations of biceps tendon, and has excellent accuracy and excellent correlation with conventional ultrasound findings.