• Journal of Biomedical Engineering Research
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• v.33 no.3
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• pp.114-127
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• 2012

Recent technical advancement allows noninvasive measurement of blood glucose. In this literature, we reviewed various noninvasive techniques for measuring glucose concentration. Optical or electrical methods have been investigated. Optical techniques include near-infrared spectroscopy, Raman spectroscopy, optical coherence technique, polarization, fluorescence, occlusion spectroscopy, and photoacoustic spectroscopy. Electrical methods include reverse iontophoresis, impedance spectroscopy, and electromagnetic sensing. Ultrasound, detection from breath, or fluid harvesting technique can be used to measure blood glucose level. Combination of various methods is also promising. Although there are many interesting and promising technologies and devices, there need further researches until a commercially available non-invasive glucometer is popular.

• Journal of Genetic Medicine
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• v.12 no.2
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• pp.72-78
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• 2015

Recently, noninvasive prenatal test (NIPT) has been adopted as a primary screening tool for fetal chromosomal aneuploidy. The principle of NIPT lies in isolating the fetal fraction of cell-free DNA in maternal plasma and analyzing it with bioinformatic tools to measure the amount of gene from the target chromosome, such as chromosomes 21, 18, and 13. NIPT will contribute to decreasing the need for unnecessary invasive procedures, including amniocentesis and chorionic villi sampling, for confirming fetal aneuploidy because of its higher positive predictive value than that of the conventional prenatal screening method. However, its greater cost than that of the current antenatal screening protocol may be an obstacle to the adoption of this innovative technique in clinical practice. Digital polymerase chain reaction (dPCR) is a novel approach for detecting and quantifying nucleic acid. dPCR provides real-time diagnostic advantages with higher sensitivity, accuracy, and absolute quantification than conventional quantitative PCR. Since the groundbreaking discovery that fetal cell-free nucleic acid exists in maternal plasma was reported, dPCR has been used for the quantification of fetal DNA and for screening for fetal aneuploidy. It has been suggested that dPCR will decrease the cost by targeting specific sequences in the target chromosome, and dPCR-based noninvasive testing will facilitate progress toward the implementation of a noninvasive approach for screening for trisomy 21, 18, and 13. In this review, we highlight the principle of dPCR and discuss its future implications in clinical practice.

• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.279-284
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• 1989

Measurement of cardiac output during exercise by noninvasive technique is very needed in the area of sports medicine. However there are only two noninvasive techniques, one of which is $CO_2$ subscript rebreathing technique and the other one is impedance cardiography. While $CO_2$ rebreathing technique needs special breathing and metablic steady state, impedance cardiography has motion Uiiau problem. In this study maior sources of the mothion artifact during treadmill exercise was found experimentally to. be the impact caused by each step on the treadmill. Thus special shoes to reduce the impact were developed. These are the shoes with silicon rubber and hard sponge attached to the soles. It was possible to measure cardiac output with the newly developed shoes for Burke protocol whose speed of the treadmill was constant 3.5 miles/hour while it was impossibel with the conventional exercise shoes.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.10 no.1
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• pp.30-36
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• 1999

Background and Objectives : Laryngeal Evoked Electromyography(EEMG) is a objective, quantitative technique to determine innervation status of larynx. The possible applications of this technique are to confirm the etiology of impaired vocal fold motion and monitor perioperative vagus nerve trauma. The purpose of this study is to develop a novel method for determining the amount of reinnervation of recurrent laryngeal nerve with accurate, inexpensive, and minimally invasive technique in human. Materials and Methods : Laryngeal EEMG was performed for 16 adults with intact vocal folds motion and 2 patients diagnosed as unilateral vocal fold paralysis. for the purpose of searching what is the optimal and noninvasive technique for laryngeal EEMG, we used 2 types of stimulation configurations(transcutaneous vs percutaneous) and 2 types of recording configurations(intramuscular vs. surface). Results and Conclusions : Percutaneous needle stimulation and surface recording of laryngeal EEMG was reliable and comparable to standard needle stimulation and invasive intramuscular needle recording. But the laryngeal EEMG by the surface recording and transcutaneous surface stimulation was not reliable and repeatable. Therefore we recommended that laryngeal EEMG by surface recording and percutaneous needle stimulation would be minimally invasive, reliable technique to know the status of reinnervation in e patients with vocal fold paralysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.126-126
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• 2009

Noninvasive plasma diagnostic technique is introduced to analyze and characterize HICP (Helmholtz Inductively Coupled Plasma) source during the plasma etching process. The HICP reactor generates plasma mainly through RF source power at 13.56MHz RF power and RF bias power of 12.56MHz is applied to the cathode to independently control ion density and ion energy. For noninvasive sensors, the RF sensor and the OES (Optical emission spectroscopy) were employed since it is possible to obtain both physical and chemical properties of the reactor with plasma etching. The plasma impedance and optical spectra were observed while altering process parameters such as pressure, gas flow, source and bias power during the poly silicon etching process. In this experiment, we have found that data measured from these noninvasive sensors can be correlated to etch results. In this paper, we discuss the relationship between process parameters and the measurement data from RF sensor and OES such as plasma impedance and optical spectra and using these relationships to analyze and characterize H-ICP source.

• Journal of Biomedical Engineering Research
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• v.3 no.2
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• pp.119-122
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• 1982

This paper presents the principles of image formation in NMR(Nuclear Magnetic Resonance) tomography. NMR tomographic imaging is a newly emerging, noninvasive, three-dimensional imaging technique. This new technique is an interdisciplinary science which encompasses the latest technologies in electrical, electronics, computers, physics, chemistry, mathematics, and medical sciences.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.859-860
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• 2006

We developed a cuffless and noninvasive measurement technique of blood pressure using tonometric pressure sensor. With observation that the maximum value of pulse pressure is not obtained at mean arterial pressure(MAP), we have figured out MAP based on the physiological characteristic including the elasticity of wrist tisse. Detecting only one part of the body and using only one device are quite advantageous over other BP measurement techniques. Our technique makes new way for the cuffless BP measurement.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.129-130
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• 1998

In this paper, We designed the ECG-NIBP-$SpO_2$ patient monitor. This production can measure Electrocardiograph, Heart Rate, Noninvasive Blood Pressure, and Oxygen Saturation for Noninvasive Mehod and can display each information. These informations were implemented by the electrodes of ECG part, the cuff of NIBP module and the finger probe with light sensor of $SpO_2$ without injection of needle or catheter. In addition, We developed a new analysis algorithm and measurement technique for NIBP and $SpO_2$ to observe patient's conditions correctly.

• Journal of Periodontal and Implant Science
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• v.47 no.1
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• pp.30-40
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• 2017

Purpose: Optical coherence tomography (OCT) is a noninvasive diagnostic technique that may be useful for both qualitative and quantitative analyses of the periodontium. Micro-computed tomography (micro-CT) is another noninvasive imaging technique capable of providing submicron spatial resolution. The purpose of this study was to present periodontal images obtained using ex vivo dental OCT and to compare OCT images with micro-CT images and histologic sections. Methods: Images of ex vivo canine periodontal structures were obtained using OCT. Biologic depth measurements made using OCT were compared to measurements made on histologic sections prepared from the same sites. Visual comparisons were made among OCT, micro-CT, and histologic sections to evaluate whether anatomical details were accurately revealed by OCT. Results: The periodontal tissue contour, gingival sulcus, and the presence of supragingival and subgingival calculus could be visualized using OCT. OCT was able to depict the surface topography of the dentogingival complex with higher resolution than micro-CT, but the imaging depth was typically limited to 1.2-1.5 mm. Biologic depth measurements made using OCT were a mean of 0.51 mm shallower than the histologic measurements. Conclusions: Dental OCT as used in this study was able to generate high-resolution, cross-sectional images of the superficial portions of periodontal structures. Improvements in imaging depth and the development of an intraoral sensor are likely to make OCT a useful technique for periodontal applications.

• Current Optics and Photonics
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• v.1 no.4
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• pp.412-420
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• 2017

Multinucleated bone resorptive osteoclasts differentiate from bone marrow-derived monocyte/macrophage precursor cells. During osteoclast differentiation, mononuclear pre-osteoclasts change their morphology and biochemical characteristics. In this study, Raman spectroscopy with multivariate techniques such as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were used to extract biochemical information related to various cellular events during osteoclastogenesis. This technique allowed for label-free and noninvasive monitoring of differentiating cells, and clearly discriminated four different time points during osteoclast differentiation. The Raman band intensity showed significant time-dependent changes that increased up to day 4. The results of Raman spectroscopy agreed with results from atomic force microscopy (AFM) and tartrate-resistant acid phosphatase (TRAP) staining, a conventional biological assay. Under AFM, normal spindle-like mononuclear pre-osteoclasts became round and smaller at day 2 after treatment with a receptor activator of nuclear $factor-{\kappa}B$ ligand and they formed multinucleated giant cells at day 4. Thus, Raman spectroscopy, in combination with PCA-LDA, may be useful for noninvasive label-free quality assessment of cell status during osteoclast differentiation, enabling more efficient optimization of the bioprocesses.