• 대한의용생체공학회:의공학회지
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• 제42권3호
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• pp.116-124
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• 2021

It is important to differentiate between the target tissue (or organ) and the rest of the tissue before incision during surgery. And when it is necessary to preserve the differentiated tissues, the blood vessels connected to the tissue must be preserved together. Various non-invasive medical imaging methods have been developed for this purpose. We aimed to develop a medical imaging system that can simultaneously apply fluorescence imaging using indocyanine green (ICG) and laser speckle contrast imaging (LSCI) using laser speckle patterns. We designed to collect images directed to the two cameras on a co-axial optical path and to compensate equal optical path length for two optical designs. The light source used for fluorescence and LSCI the same 785 nm wavelength. This system outputs real-time images and is designed to intuitively distinguish target tissues or blood vessels. This system outputs LSCI images up to 37 fps through parallel processing. Fluorescence for ICG and blood flow in animal models were observed throughout the experiment.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.143-146
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• 2004

A surface plasmon resonance (SPR) imaging system was constructed and used to detect the hexahistidine-ubiquitin-tagged human parathyroid hormone fragment (His$\sub$6/-Ub-hPTHF(1-34)) expressed in Escherichia coli. The hexahistidine-specific antibody was immobilized on a thin gold film coated with ProLinker$\^$TM/ B, a novel calixcrown derivative with a bifunctional coupling property that permits efficient immobilizaton of capture proteins on solid matrices. The soluble and insoluble fractions of an E. coli cell lysate were spotted onto the antibody-coated gold chip, which was then washed with buffer (pH 7.4) solution and dried. SPR imaging measurements were carried out to detect the expressed His$\sub$6/-Ub-hPTHF(1-34). There was no discernible protein image in the uninduced cell lysate, indicating that non-specific binding of contaminant proteins did not occur on the gold chip surface. It is expected that the approach used here to detect affinity-tagged recombinant proteins using an SPR imaging technique could be used as a powerful tool for the analyses of a number of proteins in a high-throughput mode.

• Journal of Yeungnam Medical Science
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• 제4권1호
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• pp.1-15
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• 1987

Magnetic Resonance (M.R.) is rapidly emerging technique that provides high quality images and potentially provides much more diagnostic information than do conventional imaging modalities. M.R.I. is conceptually quite different from currently used imaging methods. The complex nature of M.R.I. allows a great deal of flexibility in image product ion and available information, and key points are as follows. 1. M.R.I. offers a non-invasive technique with which to gene rate in vivo human images without ionizing radiation and with no known adverse biological effects. 2. Imaging mechanism of M.R.I. is quite different from conventional imaging modality and for more accurate diagnostic application, It is necessary for physician to understand imaging mechanism of M.R.I. 3. M.R. makes available basic chemical parameters that may provide to be useful for diagnostic medical imaging and more specific pathophysiologic information which are not available by alternate techniques. 4. M.R. can be produced by number of different methods. This flexibility allows the imaging technique to be applicated for particular clinical purpose. Multiplanar and three dimensional imaging may extend the imaging process beyond the single section available with current CT. 5. Future directions include efforts to; a. Further development of hard ware b. More fasternning scan time c. Respiratory and cardiac gated imaging d. Imaging of additional nuclei except hydrogen e. Further development of contrast media f. M.R. in vivo spectroscopy g. Real time M.R. imaging.

• Imaging Science in Dentistry
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• 제46권4호
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• pp.279-284
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• 2016

To our knowledge, the imaging features of costochondral grafts (CCGs) on cone-beam computed tomography (CBCT) have not been documented in the literature. We present the case of a CCG in the facial soft tissue to the anterior mandible, with changes mimicking a cartilaginous neoplasm. This is the first report to describe the CBCT imaging features of a long-standing graft in the anterior mandible. Implants or grafts may be incidental findings on radiographic images made for unrelated purposes. Although most are well-defined and radiographically homogeneous, being of relatively inert non-biological material, immune reactions to some grafts may stimulate alterations in the appearance of surrounding tissues. Biological implants may undergo growth and differentiation, causing their appearance to mimic neoplastic lesions. We present the case of a cosmetic autogenous CCG that posed a diagnostic challenge both radiographically and histopathologically.

• 생물정신의학
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• 제22권3호
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• pp.109-112
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• 2015

Since the early 2000s, there has been a continued interest in lie detection using functional magnetic resonance imaging (fMRI) in neuroscience and forensic sciences, as well as in newly emerging fields including neuroethics and neurolaw. Related fMRI studies have revealed converging evidence that brain regions including the prefrontal cortex, anterior cingulate cortex, parietal cortex, and anterior insula are associated with deceptive behavior. However, fMRI-based lie detection has thus far not been generally accepted as evidence in court, as methodological shortcomings, generalizability issues, and ethical and legal concerns are yet to be resolved. In the present review, we aim to illustrate these achievements and limitations of fMRI-based lie detection.

• 대한의용생체공학회:의공학회지
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• 제28권1호
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• pp.75-83
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• 2007

Elasticity is an important physical property of biological tissues. Differences in elasticity can help facilitate the diagnosis of tumors and their extent. Magnetic Resonance Elastography (MRE) tries to visualize images of tissue elasticity by externally applying shear stress on the surface of an imaging object. Applied shear stress induces internal displacements that can be measured from MR phase images. In order to conduct MRE imaging experiments, we need to first develop a vibrator. We found that there does not exist enough technical information to design the MRE vibrator. In this paper, we describe the theory, design and construction of an MRE vibrator. We report the performance of the developed vibrator using two different test methods. We found that the vibrator successfully induces enough internal displacements that can be imaged using an MRI scanner. We suggest future studies of numerous MRE imaging experiments using the vibrator.

• Journal of Chest Surgery
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• 제24권3호
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• pp.265-270
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• 1991

Since advent of the prosthetic cardiac valve replacement, much efforts for accurate assessing value function in-vivo have been attempted. To evaluate the postoperative functional and morphological status of the replaced cardiac valve prosthesis, 33 patients with valve replacement were studied by transthoracic and transesophageal 2-dimensional echocardiac imaging as well as by color Doppler flow velocity imaging. Twenty four patients had mitral valve replacement. 6 patients had aortic valve replacement and 3 patients had both mitral and aortic valve replacement. There were 34 mechanical and 2 biological prosthesis. Comparing to transthoracic echocardiography, transesophageal approach showed transvalvular regurgitant jet flow amid the prosthetic mitral valve ring during. systole and much clear visualization of cardiac chamber behind prosthesis which could give shadowing effect to ultrasound beam. According to the quantitative grading by the length and area of mitral regurgitant flow, 24 out of 27 mitral valves revealed mild degree regurgitation considered as physiological after prosthetic bileaflet valve replacement and the other 3 valves including 2 biological prosthesis had moderate degree regurgitation which was regarded as pathologic one. 2 cases of left atrial thromboses and 1 case of paravalvular leakage which were not visible by transthoracic approach were identified by transesophageal echocardiography in patients with mitral valve replacement and patients with aortic valve replacement respectively. We conclude that in patients with prosthetic mitral valve replacement, transesophageal 2-dimensional imaging with color Doppler can suggest reliable information beyond that available from the transthoracic access even though it gives patient some discomfort to proceed.

• 대한족부족관절학회지
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• 제25권3호
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• pp.117-125
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• 2021

Purpose: The aim of this study was to evaluate biological ligament healing quantitatively after suture-tape augmentation for chronic lateral ankle instability. Materials and Methods: Thirty-two patients underwent magnetic resonance imaging (MRI) at a minimum of 2 years after lateral ligament augmentation using suture-tape. Signal/noise ratios (SNRs) and widths of anterior talofibular ligaments (ATFLs) were measured on preoperative and postoperative MRI by three researchers. ATFL biological healing degrees were analyzed using changes in SNRs and widths of ATFLs and by comparing these metrics with those of normal contralateral ankles. Clinical evaluations were performed using foot and ankle outcome scores (FAOSs), Foot and Ankle Ability Measure (FAAM) scores, and ankle stress radiographs. Results: Mean FAOS and FAAM scores improved significantly from 62.4 to 93.6 and 58.3 to 92.3, respectively, at final follow-up (p<0.001). Mean SNRs and ATFL widths improved insignificantly from 8.49 to 8.21 and 2.07 to 2.15 mm, respectively, at final follow-up (p=0.424, p=0.718). Significant differences in mean SNRs and ATFL widths were found between ipsilateral and contralateral sides (p<0.001, p=0.002). Spearman's correlation analysis revealed no significant association between clinical outcomes and degrees of biological healing of ATFLs based on MRI findings. Conclusion: Despite improvements in clinical outcome measures, the effects of suture-tape augmentation for chronic lateral ankle instability on biological ligament healing were insignificant. In addition, no significant correlation was found between clinical outcomes and degrees of biological healing of ATFLs.

• 생물정신의학
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• 제11권1호
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• pp.3-13
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• 2004

Objectives:Functional magnetic resonance imaging(fMRI) is one of the most useful techniques for assessing localized changes in cerebral blood flow and oxygenation using diverse challenge paradigms. This review presents the results of fMRI studies relating to schizophrenia. Methods:Several fMRI articles on this subject in psychiatric journals were surveyed. Results:Even with some methodological limitations, most studies showed activity differences between schizophrenics and control subjects. Conclusion:fMRI extends our understanding of the pathophysiological basis of schizophrenia and offer an opportunity for the assessment and management of its pathology.

• Applied Microscopy
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• 제51권
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• pp.16.1-16.7
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• 2021

Electron microscopy (EM) is an essential imaging method in biological sciences. Since biological specimens are exposed to radiation and vacuum conditions during EM observations, they die due to chemical bond breakage and desiccation. However, some organisms belonging to the taxa of bacteria, fungi, plants, and animals (including beetles, ticks, and tardigrades) have been reported to survive hostile scanning EM (SEM) conditions since the onset of EM. The surviving organisms were observed (i) without chemical fixation, (ii) after mounting to a precooled cold stage, (iii) using cryo-SEM, or (iv) after coating with a thin polymer layer, respectively. Combined use of these techniques may provide a better condition for preservation and live imaging of multicellular organisms for a long time beyond live-cell EM.