• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제17권1호
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• pp.23-30
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• 2014

Manometry is a noninvasive diagnostic tool for identifying motility dysfunction of the gastrointestinal tract. Despite the great technical advances in monitoring motility, performance of the study in pediatric patients has several limitations that should be considered during the procedure and interpretation of the test results. This article reviews the clinical applications of conventional esophageal and anorectal manometries in children by describing a technique for performing the test. This review will develop the uniformity required for the methods of performance, the parameters for measurement, and interpretation of test results that could be applied in pediatric clinical practice.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 춘계학술대회
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• pp.184-187
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• 2018

뇌경색의 예방 및 치료에 있어서 가장 중요한 요소는 대뇌 혈류량을 증가시키는 것이다. 대뇌 혈류를 증가시키는 방법으로는 기본적으로 약물에 의한 방법과 수술 또는 동맥 내에 의료 기구를 직접 삽입하는 침습적인 시술(NeuroFloTM) 등이 있다. 본 논문에서 제안하는 비 침습적인 대뇌 혈류 증가 장치는 합병증 유발 확률이 적고, 환자의 혈압 상태에 따라 치료 수준을 정할 수 있으므로 환자의 부담을 덜어줄 수 있다. 이러한 비 침습적인 대뇌 혈류 증가 장치 구현에 있어, 환자에게 알맞은 치료 수준을 제공하기 위한 정확한 평균 동맥압 값을 측정하는 것이 중요하다. 따라서 노이즈를 제거하기 위해 아날로그 필터 및 디지털 필터를 사용하였고, 피크 값 검출을 위한 알고리즘, 펌프제어 알고리즘 등을 사용하였다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제27권2호
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• pp.79-87
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• 2024

Purpose: Recently, the prevalence of eosinophilic gastrointestinal disease (EGID) has shown an increasing trend worldwide. As the diagnosis of EGID requires invasive endoscopy with biopsy, noninvasive markers for detecting EGID in suspected patients, particularly children, are urgently needed. Therefore, this study aimed to evaluate the diagnostic accuracy of serum eosinophil cationic protein (ECP) beyond peripheral eosinophil counts in pediatric patients with EGID. Methods: Overall, 156 children diagnosed with EGID were enrolled and 150 children with functional abdominal pain disorder (FAPD) were recruited as controls. All participants underwent endoscopic biopsy in each segment of the gastrointestinal (GI) tract and serum ECP measurement, as well as peripheral eosinophil percent and absolute eosinophil count. Results: Comparing EGID (n=156) with FAPD (n=150) patients, serum ECP levels were significantly higher in pediatric patients with EGID than in those with FAPD (25.8±28.6 ㎍/L vs. 19.5±21.0 ㎍/L, p=0.007), while there was no significant difference in peripheral eosinophil percent and absolute eosinophil counts between the two groups. Serum ECP levels were correlated with peripheral eosinophil percent (r=0.593, p<0.001) and the absolute eosinophil count (r=0.660, p<0.001). The optimal cutoff value of serum ECP for pediatric EGID was 10.5 ㎍/mL, with a sensitivity of 69.9% and a specificity of 43.4% with an area under the receiver operating characteristic curve of 0.562. Conclusion: The combination of serum ECP levels and peripheral eosinophil counts, when employed with appropriated thresholds, could serve as a valuable noninvasive biomarker to distinguish between EGID and FAPD in pediatric patients manifesting GI symptoms.

• Clinical and Experimental Pediatrics
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• 제65권2호
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• pp.73-80
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• 2022

A mercury sphygmomanometer (MS) has been the gold standard for pediatric blood pressure (BP) measurements, and diagnosing hypertension is critical. However, because of environmental issues, other alternatives are needed. Noninvasive BP measurement devices are largely divided into auscultatory and oscillometric types. The aneroid sphygmomanometer, the currently used auscultatory method, is inferior to MS in terms of limitations such as validation and regular calibration and difficult to apply to infants, in whom Korotkoff sounds are not audible. The oscillometric method uses an automatic device that eliminates errors caused by human observers and has the advantage of being easy to use; however, owing to its measurement accuracy issues, the development of an international validation protocol for children is important. The hybrid method, which combines the auscultatory and electronic methods, solves some of these problems by eliminating the observer bias of terminal digit preference while maintaining measurement accuracy; however, the auscultatory method remains limited. As the age-related characteristics of the pediatric group are heterogeneous, it is necessary to reconsider the appropriate BP measurement method suitable for this indication. In addition, the mobile application-based BP measurement market is growing rapidly with the development of smartphone applications. Although more research is still needed on their accuracy, many experts expect that mobile application-based BP measurement will effectively reduce medical costs due to increased ease of access and early BP management.

• Journal of Chest Surgery
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• 제20권2호
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• pp.223-229
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• 1987

Doppler echocardiography provides valuable information regarding prosthetic heart valve function rather than structure. There are three methods of expressing the severity of mitral valve obstruction: the transvalvular pressure gradient, effective valve area, and pressure half-time. Of these, the transvalvular pressure gradient [~p] can be determined by the measurement of maximum transvalvular blood flow velocity [V] according to the modified Bernoulli`s equation [gp=4V*]. Eleven patients, who underwent mitral valve replacement with Duromedics mechanical prostheses, and 17 normal persons were investigated. There were significantly higher calculated pressure gradients in prosthetic than normal mitral valves [9.*10*2.22mmHg-vs-3.26*0.99mmHg:p<0,01], and there was a inverse relationship between pressure gradient and prosthetic valve size [11.17*0.%mmHg in size 27mm and 29mm -v- 7.38*1.12mmHg in size 31mm and 33mm; r=0.85, p<0.01] The noninvasive Doppler technique should be useful in the diagnosis of prosthetic valve obstruction.

• 융합신호처리학회논문지
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• 제14권1호
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• pp.1-5
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• 2013

The two major problems related to the blood flow in replaced prosthetic heart valve are thrombus formation and hemolysis. Reliability of prosthetic valve is very important because its failure means the death of patient. There are many factors affecting the valvular failures and their representatives are mechanical failure and thrombosis, so early noninvasive detection is essentially required. The purpose of this study is to detect the various thromboses formation by using acoustic signal acquisition and its spectral analysis on the frequency domain. We made the thrombosis models using Polydimethylsiloxane (PDMS) and they are thrombosis model on the disc, around the sewing ring and fibrous tissue growth across the orifice of valve. Using microphone and amplifier, we measured the acoustic signal from the prosthetic valve, which is attached to the pulsatile mock circulation system. A/D converter sampled the acoustic signal and the spectral analysis is the main algorithm for obtaining spectrum. Then the spectrum of normal and 5 different kinds of abnormal valve were obtained. Each spectrum waveform shows a primary and secondary peak. The secondary peak changes according to the thrombus model. To quantitatively distinguish the frequency peak of the normal valve from that of the thrombosed valves, analysis using a neural network was employed. Acoustic measurement has been used as a noninvasive diagnostic tool and is thought to be a good method for detecting possible mechanical failure or thrombus.

• 대한한방내과학회지
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• 제36권2호
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• pp.85-92
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• 2015

Objectives: The liver fibroscan has been developed as a noninvasive and convenient method to assess hepatic fibrosis. This study aimed to review this device in terms of its technological concept and clinical application in traditional Korean medicine (TKM). Methods: The technological background, diagnostic evaluation, and clinical usefulness of fibroscan were reviewed using various literature and clinical studies. One clinical example-a patient with hepatofibrosis who had been treated with TKM-is presented. Results: The liver fibroscan was approved as a medical device for noninvasive measurement of the hepatic fibrosis level by the Korean Food and Drug Administration (KFDA). Numerous clinical studies have confirmed that its sensitivity and specificity allow it to serve as a substitute for liver biopsy, the present gold standard diagnostic method. The accuracy and reproducibility and lack of technical risks are strong points of the fibroscan; however, it has some limitations for application, especially in patients with obesity or severe hepatitis. One clinical example showed the applicability of the liver fibroscan in herbal medicine-based treatments. Conclusions: The requirement for diagnostic medical devices is an important issue in TKM; therefore, this study provides valuable information for practitioners of TKM.

• 한국정밀공학회지
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• 제21권11호
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• pp.209-218
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• 2004

The purpose of this paper is to suggest a practical and simple method for the identification of the joint mechanical properties and to apply it to human knee joints. The passive moment at a joint was modeled by three mechanical parts, that is, a gravity term, a linear damper term and a nonlinear spring term. Passive pendulum tests were performed in 5 fat and 5 thin men. The data of pendulum test were used to identify the mechanical properties of joints through sequential quadratic programming (SQP) with random initial values. The identification was successful where the normalized root-mean-squared (RMS) errors between the simulated and experimental joint angle trajectories were less than 10％. The parameter values of mechanical properties obtained in this study agreed with literature. The inertia, gravity and the damping constant were greater at fat men, which indicates more resistance to body movement and more energy consumption fer fat men. The suggested method is noninvasive and requires simple setup and short measurement time. It is expected to be useful in the evaluation of joint pathologies.

• 대한의용생체공학회:의공학회지
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• 제36권6호
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• pp.241-250
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• 2015

Noninvasive temperature monitoring is feasible with Magnetic Resonance Imaging (MRI) based on temperature sensitive MR parameters such as $T_1$ and $T_2$ relaxation times, Proton Resonance Frequency shift (PRFs), diffusion, exchange process, magnetization transfer contrast, chemical exchange saturation transfer, etc. While the temperature monitoring is very useful to guide the thermal treatment such as RF hyperthermia or thermal ablation, the optimization of the MR thermometry method is essential because the range of temperature measurement depends on the choice of the measurement methods. Useful temperature range depends on the purpose of treatment methods, for example, $42^{\circ}C$ to $45^{\circ}C$ for RF hyperthermia and over $50^{\circ}C$ for thermal ablation. In this paper, MR thermometry methods using $T_1$ and $T_2$ relaxation times and PRFs-based MR thermometry are tried on a 3.0 T MRI system and their results are reported and compared. In addition, the scanning protocol and temperature calculation algorithms from $T_1$ and $T_2$ relaxation times and PRFs are optimized for the different temperature ranges for the purpose of RF hyperthermia and/or thermal ablation.

• 기본간호학회지
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• 제8권3호
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• pp.366-378
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• 2001

Objective: The purpose of this study was to identify differences in measurement methods for blood pressure (Direct measurement, HP automatic indirect measurement, and SE 7000 Korean made indirect measurement), and to evaluate the clinical trial of the Korean made automatic indirect blood pressure measurement. Material & Methods: From June, 1999 to February, 2000, fifty five consecutive patients were randomized into hypertension group (n=20), normotension group (n=20), and hypotension group (n= 15). Measuring blood pressure by indirect methods (HP NIBP M 1008B and SE 7000 NIBP Korean made) was done simultaneously in the same arm with arterial line for direct blood pressure measurement (HP M1006A). The procedures were repeated ten times at intervals of 2 minutes. Statistical analysis was Performed using SPSS (version 8.0 for windows) software package. Values were expressed as means and standard deviation and means were compared using t-test. Statistical significance was considered present with a p value less than 0.05. Results: In the hypertension group and noromotension group, the disparity between HP direct measurement and indirect SE 7000 NIBP did not show any differences compared to the disparity between HP direct measurement and indirect HP NIBP. In the hypotension group, the disparity in the diastolic pressure between HP direct measurement and indirect SE 7000 NIBP was significantly different compared to the disparity between HP direct measurement and indirect HP NIBP (p<0.001), however, disparities in systolic pressure did not showed any differences. Conclusion: Direct blood pressure measurement (HP M1006A) can be replaced with indirect blood pressure measurements (HP NIBP M 1008B & SE 7000 NIBP) in normotension and hypertension patients. Korean made indirect measurement was found to be more accurate compared to HP indirect measurement in hypotension Patients, but more study is needed.