• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.571-584
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• 2004

Magnetic Resonance Imaging (MRI) is one of the most advanced imaging techniques in clinical and research medicine. However, clinical application of MRI to the lung or thorax has been limited due to various drawbacks. Low signal intensity of the lung and cardiac and respiratory movements are the most serious problems with MRI in thorax. Nevertheless, MRI is superior to CT in some selected patients with thoracic diseases. The role of clinical MRI in thoracic disease has been widened with improvement of MR equipments and development of new pulse sequences. Otherwise, functional assessment of lung by MRI has been studied for the last decade. These include perfusion MRI with or without contrast enhancement and ventilation MRI with oxygen-enhancement or hyperpolarized noble gas, $^3He$ and $^{129}Xe$.

• Korean Journal of Clinical Laboratory Science
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• v.37 no.2
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• pp.123-128
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• 2005

Magnetoencephalography (MEG) is the measurement of the magnetic fields produced by electrical activity in the brain, usually conducted externally, using extremely sensitive devices such as Superconducting Quantum Interference Device (SQUID). MEG needs complex and expensive measurement settings. Because the magnetic signals emitted by the brain are on the order of a few femtoteslas (1 fT = 10-15T), shielding from external magnetic signals, including the Earth's magnetic field, is necessary. An appropriate magnetically shielded room is very expensive, and constitutes the bulk of the expense of an MEG system. MEG is a relatively new technique that promises good spatial resolution and extremely high temporal resolution, thus complementing other brain activity measurement techniques such as electroencephalography (EEG), positron emission tomography (PET), single-photon emission computed tomography (SPECT) and functional magnetic resonance imaging (fMRI). MEG combines functional information from magnetic field recordings with structural information from MRI. The clinical uses of MEG are in detecting and localizing epileptic form spiking activity in patients with epilepsy, and in localizing eloquent cortex for surgical planning in patients with brain tumors. Magnetoencephalography may be used alone or together with electroencephalography, for the measurement of spontaneous or evoked activity, and for research or clinical purposes.

• Investigative Magnetic Resonance Imaging
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• v.19 no.1
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• pp.52-55
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• 2015

Supradiaphragmatic liver is a rare condition. Establishing an accurate preoperative diagnosis is difficult. Operative exploration is necessary to differentiate this lesion from intrathoracic masses, such as a pleural based tumor, diaphragmatic tumor and peripheral lung tumor. However, with the aid of the hepatocyte-specific magnetic resonance imaging contrast agent, gadoxetic acid (Gd-EOB-DTPA), functional hepatocytes in the lesion can be identified in the hepatobiliary phase, potentially allowing an accurate and non-invasive diagnosis. We report a case of supradiaphragmatic liver diagnosed by Gd-EOB-DTPA-enhanced magnetic resonance imaging.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2003.11a
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• pp.191-191
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• 2003

• Proceedings of the KSMRM Conference
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• 1996.10a
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• pp.79-84
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• 1996

• Dementia and Neurocognitive Disorders
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• v.16 no.2
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• pp.48-53
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• 2017

Background and Purpose Torrance Tests of Creative Thinking (TTCT) is a well-known and commonly used measure of creativity. However, the TTCT-induced creative hemodynamic brain activity is rarely revealed. The purpose of this study is to elucidate the neural correlates of creative thinking in the setting of a modified version of the figural TTCT adapted for an functional magnetic resonance imaging (fMRI) experiment. Methods We designed a blocked fMRI experiment. Twenty-five participants (11 males, 14 females, mean age $19.9{\pm}1.8$) were asked to complete the partially presented line drawing of the figural TTCT (creative drawing imagery; creative). As a control condition, subjects were asked to keep tracking the line on the screen (line tracking; control). Results Compared to the control condition, creative condition revealed greater activation in the distributed and bilateral brain regions including the left anterior cingulate, bilateral frontal, parietal, temporal and occipital regions as shown in the previous creativity studies. Conclusions The present revealed the neural basis underlying the figural TTCT using fMRI, providing an evidence of brain areas encompassing the figural TTCT. Considering the significance of a creativity test for dementia patients, the neural correlates of TTCT elucidated by this study may be valuable to evaluate the brain function of patients in the clinical field.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.1
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• pp.1725-1733
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• 2019

Background: In some clinical guidelines followed in clinical practice, nonsurgical treatments are recommended as the primary intervention for patients with lumbar disc herniation (LDH). However, the effect of a therapeutic exercise program based on stabilization of the lumbar spine for treatment of multilevel LDH has not been evaluated thoroughly. Objective: To investigate the effects of therapeutic exercise on pain, physical function, and magnetic resonance imaging (MRI) findings in a patient with multilevel LDH. Design: Case Report Methods: A 43-year-old female presented with low back pain, radicular pain and multilevel LDH (L3-L4, L4-L5, L5-S1). The therapeutic exercise program was conducted. in 40-min sessions, three times a week, for 12 weeks. Low back and radicular pain, lumbar disability, and physical function were measured before and after 6 and 12 weeks of the exercise program. MRI was performed before and after 12 weeks of the program. Results: After 6 and 12 weeks of the therapeutic exercise, low back and radicular pain and lumbar disability had decreased, and lumbar range of motion (ROM) was improved bilaterally, compared with the initial values. Also improved at 6 and 12 weeks were isometric lumbar strength and endurance, and the functional movement screen score. The size of disc herniations was decreased on MRI obtained after 12 weeks of therapeutic exercise than on the pre-exercise images. Conclusions: We observed that therapeutic exercise program improved spinal ROM, muscle strength, functional capacity, and size of disc herniation in LDH patient.

• The Korean Journal of Applied Statistics
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• v.34 no.2
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• pp.127-139
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• 2021

Independent Component Analysis is a popular statistical method to separate independent signals from the mixed data, and Group Independent Component Analysis is an its multi-subject extension of Independent Component Analysis. It has been applied Functional Magnetic Resonance Imaging data and provides promising results. However, classical Group Independent Component Analysis works poorly when outliers exist on data which is frequently occurred in Magnetic Resonance Imaging scanning. In this study, we propose a robust version of the Group Independent Component Analysis based on ROBPCA. Through the numerical studies, we compare proposed method to the conventional method, and verify the robustness of the proposed method.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.66-74
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• 1997

fMRI, functional MRI introduced receently appears based on the gradient echo technique which is sensitive to the field inhomogeneity developed due to the local susceptibility changes of blood oxygenation and deoxygenation. There has been many variants of the basic gradient echo sequence which is sensitive to the local inhomogeniety, among others such as GRASS or SSFP to EPISTAR are the most commonly used gradient echo techniques. Common to all these gradient echo techniques is that the signal due to the susceptibility effects is generally decreased with increasing inhomogeneity due to the $T2^{*}$ effect or conventionally konwn as blood oxygenation level dependent(BOLD) effect. It is, also found that the BOLD sensitivity is also dependent on the imaging modes, namely whether the imaging is in axial, or coronal or sagittal mode as well as the directions of the vessels against the main magnetic field. We have, therefore, launched a systematic study of imaging mode dependent signal change or BOLD sensitivity as well as the signal changes due tothe tilting angle of the imaging planes. Study has been made for both TRFGE sequence and CGE sequence to compare the distinctions of the each mode since each technique has different sensitivity againsst susceptibility effect. Method of computation and both the computer simulations and their corresponding experimental results are presented.

• Proceedings of the KOSOMBE Conference
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• v.1993 no.05
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• pp.21-24
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• 1993

The experimental results of visual stimulation with the tailored RF pulse are reported. Tailored RF pulse is used for the susceptibility effect imaging. Around 25% signal change of visual cortex area is detected during photic stimulation. Interestingly, with the tailored RF pulse, the signal intensity of visual cortex is deceased during photic stimulation. It is, however, increased with normal $T_2$ weighted imaging. The comparison between normal $T_2$ weighted imaging and the tailored RF pulse imaging are performed with 4T NMR system and the results with human volunteer are also presented.