Kim, Jung-Man;Kim, Tae-Hyung;Im, Dong-Sun;Kang, Min-Gu;Lee, Kyu-Jo
The Journal of Korean Orthopaedic Ultrasound Society
/
v.4
no.1
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pp.7-14
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2011
Purpose: The purpose of this study was to analyze the correlation between the medial joint space on weight bearing simple X-ray and the ultrasonographic articular cartilage thickness. Materials and Methods: The articular cartilage thickness of 91 osteoarthritic knees of 73 patients were measured with weight bearing simple X-ray and ultrasonography between June 2010 and September 2010. Male were 13 and female were 60. Right knees were 35, left knees were 20 and bilateral involvements were 18. Medial joint spaces on X-ray were measured in full extension view and $45^{\circ}$ PA(Rosenberg) view. Femoral cartilage thicknesses at and those at the point between the middle 1/3 and posterior 1/3 area were measured by ultrasonography, that were scanned coronally at $30^{\circ}$ flexion and $130^{\circ}$ flexion respectively. The results were analyzed statistically by Pearson correlation test and Bland-Altman plot test. Results: Medial joint spaces measured in full extension view and femoral articular cartilage thicknesses at the point between the anterior 1/3 and middle 1/3 area measured with sonography were statistically correlated and medial joint spaces measured in $45^{\circ}$ PA view and those at the point between the middle 1/3 and posterior 1/3 area measured with sonography were also correlated (P<0.05, $SD{\pm}2$). Conclusion: The measurement of articular cartilage thicknesses by the ultrasonography was easy even in the patient who are unable to take weight bearing view and was thought to be a useful diagnostic and follow up method to examine the degenerative change in addition to simple radiographic examination in the knee osteoarthritis.
Ahn, Yeh-Chan;Oak, Chulho;Park, Jung-Eun;Jung, Min-Jung;Kim, Jae-Hun;Lee, Hae-Young;Kim, Sung Won;Park, Eun-Kee;Jung, Maan Hong
Journal of the Optical Society of Korea
/
v.20
no.5
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pp.607-613
/
2016
The pleura is known as an end target organ of exposure to toxic environmental materials such as fine particulate matter and asbestos. Moreover, long-term exposure to hazardous materials can eventually lead to fatal lung disease such as diffuse pleural fibrosis or mesothelioma. Chest computed tomography (CT) and ultrasound are gold standard imaging modalities for detection of advanced pleural disease. However, a diagnostic tool for early detection of pleural reaction has not been developed yet due to difficulties in imaging ultra-fine structure of the pleura. Optical coherence tomography (OCT), which provides cross-sectional images of micro tissue structures at a resolution of 2-10 μm, can image the mesothelium with a thickness of ~100 μm and therefore enables investigation of the early pleural reaction. In this study, we induced the early pleural reaction according to a time sequence after pleurodesis using talc, which has been widely used in the clinical field. The pleural reaction in talc grouped according to the time sequence (1st, 2nd, 4th weeks) showed a significant thickening (average thickness: 45 ± 7.5 μm, 80 ± 10.7 μm, 90 ± 12.5 μm), while the pleural reaction in sham and normal groups showed pleural change from normal to minimal thickening (average thickness: 16 ± 5.5 μm, 17 ± 4.5 μm, 15 ± 6.5 μm, and 12 ± 7.5 μm, 13 ± 2.5 μm, 12 ± 3.5 μm). The measurement of pleural reaction by pathologic examinations was well-matched with the measurement by OCT images. This is the first study for measuring the thickness of pleural reactions using a biophotonic modality such as OCT. Our results showed that OCT can be useful for evaluating the early pleural reaction.
So Yeon Won;Eun-Kyung Kim;Hee Jung Moon;Jung Hyun Yoon;Vivian Youngjean Park;Min Jung Kim
Journal of the Korean Society of Radiology
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v.81
no.1
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pp.147-156
/
2020
Purpose The objective of this study was to evaluate the diagnostic value and threshold levels of cytokeratin fragment 21-1 (CYFRA 21-1) in fine-needle aspiration (FNA) washouts for detection of lymph node (LN) recurrence in postoperative breast cancer patients. Materials and Methods FNA cytological assessments and CYFRA 21-1 measurement in FNA washouts were performed for 64 axillary LNs suspicious for recurrence in 64 post-operative breast cancer patients. Final diagnosis was made on the basis of FNA cytology and follow-up data over at least 2 years. The concentration of CYFRA 21-1 was compared between recurrent LNs and benign LNs. Diagnostic performance and cut-off value were evaluated using a receiver operating characteristic curve. Results Regardless of the non-diagnostic results, the median concentration of CYFRA 21-1 in recurrent LNs was significantly higher than that in benign LNs (p < 0.001). The optimal diagnostic cut-off value was 1.6 ng/mL. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CYFRA 21-1 for LN recurrence were 90.9%, 100%, 100%, 98.1%, and 98.4%, respectively. Conclusion Measurement of CYFRA 21-1 concentration from ultrasound-guided FNA biopsy aspirates showed excellent diagnostic performance with a cut-off value of 1.6 ng/mL. These results indicate that measurement of CYFRA 21-1 concentration in FNA washouts is useful for the diagnosis of axillary LN recurrence in post-operative breast cancer patients.
Kim, Jung-Man;Ra, Ki-Hang;Nam, Ho-Jin;Lee, Jung-Woo
The Journal of Korean Orthopaedic Ultrasound Society
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v.3
no.1
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pp.15-20
/
2010
Purpose: The goal of this study is to find out how useful ultrasonography is in measuring amount of effusion within the knee joint in comparison with physical examination and simple radiography. Materials and Methods: We evaluated total 60 cases which were suspicious for joint effusion. Average age was 61.3 years. The group was consisted of 22 males and 38 females, and 24 obese people and 36 non-obese people. Stroke test and patella floating test were done as physical examination. Amount of joint effusion was classified into 3 groups in simple lateral radiographic view and ultrasonography was used for recheck-up. Results: 39 cases were found positive in stroke test, and patella floating was shown in 20 cases. In simple lateral radiographic view, 47 cases of grade I, 7 cases of grade II and 3 cases of grade III were checked. Average $7.67{\pm}2.90mm$ amount of effusion was checked by ultrasonography. Amount of fluid in stroke test, patella floating test and simple lateral radiographic view showed close correlation with ultrasonography. Gender did not seem to affect physical examination, but strong correlation was found in female in simple radiography. Obese group showed closer relationship with all 3 exams compared with non-obese group. Physical examination was relatively effective with nonobese group, but not with obese group. And it was not easy to measure the amount of fluid with simple radiographic view, but we could obtain objective data from ultrasonography by measuring the amount of effusion dynamically. Conclusion: We concluded that more objective data was obtained with ultrasonography in comparison with physical examinations and simple radiography in the aspect of measuring amount of joint fluid.
Park, Kye-Hyun;Chae, Hurn;Yun, Yang-Ku;Lee, Jae-Woong;Kim, Kwhan-Mien;Jun, Tae-Gook;Kim, Jhin-Gook;Shim, Young-Mog;Park, Pyo-Won
Journal of Chest Surgery
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v.30
no.8
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pp.760-769
/
1997
This study aimed to determine factors that influence blood flow through coronary bypass grafts and to analyze relationship between the graft flow and postoperative outcome. Blood flow through 146 bypass grafts(GBF) was measured with transit-time ultrasound flowmeter during coronary artery bypass grafting operations in 50 patients. Single and multiple regression analyses were done for relationships between the GBF and four variables: internal diameter of recipient coronary artery, myocardial value of bypassed branch(es), type of graft, and finding of preoperative myocardial perfusion scan. The relationship between GBF and postoperative scan finding was also analyzed. 1. The mean GBF was significantly higher in sequential grafts than in single vein grafts or in internal thoracic artery grafts(61.5 vs. 46.9 and 42.5 ml/min). 2. Myocardial value and recipient artery diameter were found to be the factors determining GBF. There was no correlation between GHF and presence of perfusion defect in the preoperative scan. 3. Myocardial value was found to be more important than recipient artery diameter in determinintg GBF. 4. Reversible perfusion defects were more frequently found in the areas upplied by grafts with low GBP. But this fact had only mild statistical significance. These results suggest that blood flow through a bypass graft is more determined by the size of its supplyinf: myocardium than by the size of recipient artery. So, we can expect effective improvement in myocardial flow reserve after grafting of small(1~1.5mm) coronary arteries, if they supply substantial area of myocardium.
The study was conducted surveying ultrasound room workers on hospital infection awareness in Daejeon and Choong-chunng region. The contamination of ultrasonic probes used in clinical trials was measured using ATP, and the results were verified after using 70% alcohol sterilization. It was measured on the group's general characteristics and the specific categories such as academic background, job type, having professional certificate and infection education. After the examination, the gel removal and method, disinfection status of the probe and variable correlation analysis were performed to analyze the recognition of the ultrasonic probe disinfection. After examination in ultrasound room, it was found that towels were used the most for cleaning, and the gel container was not replaced for more than three months. After 70% alcohol disinfection, ATP contamination was reduced from $1055.4{\pm}944.2$ to $133.5{\pm}93.2$ and the result was analyzed to be statistically significant.(${\rho}<0.01$) The found bacteria were CNS, Gram positive bacillus, and Micrococcus specs. In order to solve this problem, 70% alcohol sterilization was applied and the bacteria were not detected after the treatment. The research shows that regular training on infection control and efforts to prevent infection are necessary, and that 70% alcohol is effective in disinfect the bacteria. Therefore, the medical institution should provide active hospital infection control education to improve the awareness of hospital infection among workers and contribute to the prevention of patient infection. It is also understood that proper use of the results of this study will help prevent infection by means of ultrasonic probes.
For application to several MHz photoacoustic imaging systems, a needle hydrophone was designed and fabricated by using PMN-PZT piezoelectric single crystal, and its characteristics were evaluated through comparison with a commercial PVDF(Polybinylidene Fluoride) hydrophone of which receiving sensitivity is known. The simulation using the KLM model results show that the peak receiving impulse response for $50{\Omega}$ terminating impedance of the fabricated hydrophone is -261.6 dB re $1V/{\mu}Pa$ and the frequency response is relatively flat over 2 ~ 12 MHz with fluctuation less than 5 dB. The measurement results using tone burst signals also show that it has higher (ave. 10.9 dB) sensitivity than the commercial hydrophone in 2 ~ 8 MHz, and the receiving sensitivity of $-255.8{\pm}2.8$ dB re $1V/{\mu}Pa$ was measured for the fabricated hydrophone. In addition, it is known that the photoacoustic signals and the image of a hair obtained by a mechanical scanned photoacoustic imaging system with the fabricated hydrophone were bigger and better than those obtained with the commercial hydrophone.
Kim, Tae Hoon;Hahn, Joohee;Jeong, Ju-Ri;Lee, Changjoo;Kim, You Jin;Choi, Sung Min;Jeon, Da Young;Lee, Jin Hwa;Lim, In-Hyuk;Lee, Wan-Hee
Physical Therapy Rehabilitation Science
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v.5
no.4
/
pp.210-214
/
2016
Objective: The aim of this study was to measure the muscle architectural parameters of abdominal muscles in healthy individuals by rehabilitative ultrasound imaging (RUSI) and to investigate their changes after bridging exercise in various environments. Design: Cross-sectional study. Methods: The study included 40 healthy participants (19 men, 21 women). Subjects were randomly allocated to a stable surface group (SG, n=20) or an unstable surface group (UG, n=20). The participants assumed three positions in rest, bridging exercise with knee flexion $60^{\circ}$, and bridging exercise with knee flexion $90^{\circ}$ for the measurement of abdominal muscle thickness by RUSI. For the resting position, the participants held the head neutral in a hook-lying position and the dominant side was measured. For contraction, the participants performed the bridging exercise with the knee joint in $60^{\circ}$ and $90^{\circ}$ of flexion for 10 seconds each. Results: For transversus abdominis, external oblique muscle thickness, within the stable surface group and the unstable surface group, no significant contraction difference was observed in both the $60^{\circ}$ and $90^{\circ}$ bridge exercise conditions. Contraction difference of internal oblique muscle was significantly larger at $90^{\circ}$ than at $60^{\circ}$ within the SG (p<0.05). But within the UG, no significant contraction difference was shown. There was no significant contraction difference between the surface group and the unstable SG at $60^{\circ}$ condition and at $90^{\circ}$ condition in all measured muscles. Conclusions: The contraction difference is different for each muscle during bridge exercise with knee flexion $60^{\circ}$ and bridging exercise with knee flexion $90^{\circ}$. Muscle contraction difference is generally large when exercised on an unstable surface than a stable surface, but these are not statistically significant when bridging exercise is performed using dynamic air cushion for unstable surface.
Kim, Jongbeom;Lee, KyoungJun;Jhang, Kyung-Young;Kim, ChungSeok
Journal of the Korean Society for Nondestructive Testing
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v.34
no.3
/
pp.220-225
/
2014
Generally, the nonlinearity of ultrasonic waves is measured using a nonlinear parameter ${\beta}$, which is defined as the ratio of the second harmonic's magnitude to the power of the fundamental frequency component after the ultrasonic wave propagates through a material. Nonlinear parameter ${\beta}$ is recognized as an effective parameter for evaluating material degradation. In this paper, we evaluated the nonlinear parameter of Al6061-T6 which had been subjected to an artificial aging heat treatment. The measurement was using the transmitted signal obtained from contact-type transducers. After the ultrasonic test, a micro Vickers hardness test was conducted. From the result of the ultrasonic nonlinear parameter, the microstructural changes resulting from the heat treatment were estimated and the hardness test proved that these estimates were reasonable. Experimental results showed a correlation between the ultrasonic nonlinear parameter and microstructural changes produced by precipitation behavior in the material. These results suggest that the evaluation of mechanical properties using ultrasonic nonlinear parameter ${\beta}$ can be used to monitor variations in the mechanical hardness of aluminum alloys in response to an artificial aging heat-treatment.
This study presents an automatic system to predict parturition time in the crated sows. The system relies on ultrasonic transducers mounted from above along the length of the crate. Using a 40 kHz time of flight (TOF) single envelope wave, the momentary distances between the sensors are measured. Therefore, the local momentary height of the sow and the momentary posture, i.e. standing posture (SDP), kneeling posture (KP), sitting posture (STP) and lateral lying posture (LLP) are determined. Crated sows change their postures from standing to lying and vice versa which follows a characteristic pattern. As parturition approaches, sows exhibit uneasiness, restlessness and the stand up sequence (SUS, the posture transition from LLP to SDP) rate increases because of labor pains. In time series, the SUS rate demonstrates a peak and it happens approximately 0-12 h before parturition. In this paper, the basic parturition threshold value method (BPTVM) and the same hour method (SHM) are proposed for predicting parturition, both of which are based on the SUS rate. The BPTVM mainly detects the peak of the SUS rate. As the SUS rate exceeds the threshold value, the parturition becomes predictable. Moreover, the SHM calculates the difference in the SUS rates between a particular time of day and the corresponding time of the preceding day. Compared to the BPTVM, the SHM can eliminate the circadian rhythm of the SUS rate influenced by feeding behavior. Using the SHM the parturition can be approximately predicted within hours. In an attempt to define the threshold parameters of predicting parturition, a data set with 32 sows of the SUS rate are used to estimate assumable predicting probability. The results show the assumable probability of the parturition prediction within 9 h is 96.9% for the SHM and 84.4% for the BPTVM. Moreover, the SHM can even reach a 75% probability of prediction within three hours of parturition. We conclude that the SHM is more accurate and is more useful for parturition time prediction. When parturition is detected, the proposed algorithm generates a warning signal which can inform human personnel to protect the mother and newborn piglets.
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