• Investigative Magnetic Resonance Imaging
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• 제25권4호
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• pp.218-228
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• 2021

Due to their high degree of freedom to transfer and acquire light, fiber optics can be used in the presence of strong magnetic fields. Hence, optical sensing and imaging based on fiber optics can be integrated with magnetic resonance imaging (MRI) diagnostic systems to acquire valuable information on biological tissues and organs based on a magnetic field. In this article, we explored the combination of MRI and optical sensing/imaging techniques by classifying them into the following topics: 1) functional near-infrared spectroscopy with functional MRI for brain studies and brain disease diagnoses, 2) integration of fiber-optic molecular imaging and optogenetic stimulation with MRI, and 3) optical therapeutic applications with an MRI guidance system. Through these investigations, we believe that a combination of MRI and optical sensing/imaging techniques can be employed as both research methods for multidisciplinary studies and clinical diagnostic/therapeutic devices.

• Investigative Magnetic Resonance Imaging
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• 제25권2호
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• pp.59-75
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• 2021

The fornix is the major white-matter outflow tract from the hippocampus; it has a significant role in cognitive function. It is readily imaged via magnetic resonance imaging; its main parts are the crura, commissure, body, and columns. In this pictorial essay, we describe and illustrate the functional and imaging anatomy of the fornix and limbic system, as well as various disease entities involving the fornix.

• Applied Microscopy
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• 제46권4호
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• pp.179-183
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• 2016

Mapping brain structural and functional connections through the whole brain is essential for understanding brain mechanisms and the physiological bases of brain diseases. Although region specific structural or functional deficits cause brain diseases, the changes of interregional connections could also be important factors of brain diseases. This review will introduce common neuroimaging modalities, including structural magnetic resonance imaging (MRI), functional MRI (fMRI), diffusion tensor imaging, and other recent neuroimaging analyses methods, such as voxel-based morphometry, cortical thickness analysis, local gyrification index, and shape analysis for structural imaging. Tract-Based Spatial Statistics, TRActs Constrained by UnderLying Anatomy for diffusion MRI, and independent component analysis for fMRI also will also be introduced.

• Investigative Magnetic Resonance Imaging
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• 제1권1호
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• pp.42-50
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• 1997

• 한국자기공명학회:학술대회논문집
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• 한국자기공명학회 2002년도 International Symposium on Magnetic Resonance
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• pp.36-37
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• 2002

• Investigative Magnetic Resonance Imaging
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• 제26권2호
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• pp.117-124
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• 2022

Purpose: In this study, we provide a way to assess even a slight effect of exercise on trunk-muscle activity. Materials and Methods: Seven healthy male participants (mean age, 24.7 ± 3.2 years; height, 171.2 ± 9.8 cm; and weight, 63.8 ± 11.9 kg) performed 15 sets of an exercise with 20 repetitions of 90° hip and right-knee flexion while lying supine. The exercise intensity was measured using the 10-point Rating of Perceived Exertion Scale after the first and 15th sets of exercises. Although cross-sectional areas and functional T2 mapping using ultrafast imaging (fast-acquired muscle functional magnetic resonance imaging, fast-mfMRI) have been proposed for imaging to evaluate exercise-induced muscle activity in real time, no previous studies have reported on the evaluation of trunk-muscle activity using functional T2 mapping. As a method for assessing trunk-muscle activity, we compared functional T2 mapping using ultrafast imaging (fast-mfMRI) with cross-sectional areas. Results: Although the muscle cross-sectional areas were increased by the exercise, there was no significant difference at rest. On the other hand, for all sets, the changes in T2 were significant compared with those at rest (P < 0.01). These results demonstrate that T2, calculated from fast-mfMRI images can be used to detect even a small amount of muscle activity induced by acute exercise, which was impossible to do with cross-sectional areas. Conclusion: Fast-mfMRI, which can also display functional information with detailed forms, enabled non-invasive real-time imaging for identifying and evaluating the degree of deep trunk-muscle activity induced by exercise.

• Investigative Magnetic Resonance Imaging
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• 제21권2호
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• pp.91-96
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• 2017

Purpose: To describe technical methods for functional magnetic resonance imaging (fMRI) study with arterial spin labeling (ASL) compared to blood oxygenation level-dependent (BOLD) technique and discuss the potential of ASL for research and clinical practice. Materials and Methods: Task-based (n = 1) and resting-state fMRI (rs-fMRI) (n = 20) were performed using ASL and BOLD techniques. Results of both techniques were compared. Results: For task-based fMRI with finger-tapping, the primary motor cortex of the contralateral frontal lobe and the ipsilateral cerebellum were activated by both BOLD and ASL fMRI. For rs-fMRI of sensorimotor network, functional connectivity showed similar results between BOLD and ASL. Conclusion: ASL technique has potential application in clinical and research fields because all brain perfusion imaging, CBF measurement, and rs-fMRI study can be performed in a single acquisition.

• Korean Journal of Radiology
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• 제20권6호
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• pp.894-908
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• 2019

Kidney transplantation is the treatment of choice for patients with end-stage renal disease, as it extends survival and increases quality of life in these patients. However, chronic allograft injury continues to be a major problem, and leads to eventual graft loss. Early detection of allograft injury is essential for guiding appropriate intervention to delay or prevent irreversible damage. Several advanced MRI techniques can offer some important information regarding functional changes such as perfusion, diffusion, structural complexity, as well as oxygenation and fibrosis. This review highlights the potential of multiparametric MRI for noninvasive and comprehensive assessment of renal allograft injury.

• Investigative Magnetic Resonance Imaging
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• 제10권1호
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• pp.26-31
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• 2006

목적 : 감각 및 운동기능에 대한 기능적 자기공명영상에서 데이터 분석 시 global scaling이 뇌 활성화 영상에 미치는 영향을 알아보고자 하였다. 대상 및 방법 : 신경학적 병력이 없는 정상 성인 피검자 4명을 대상으로 하였다. 운동기능은 오른쪽 상지를 구부렸다가 폈다가를 반복하는 운동을 시행하였고 청각기능은 1 KHz 순음자극을 시행하였다. 기능적 자기공명영상은 3.0T 자기공명영상기기(GE, Milwaukee, USA)에서 BOLD-EPI 기법을 사용하였고 데이터 분석은 SPM2를 사용하였다. 데이터 분석 시 움직임 보정, 통계적 유의 수준 등은 동일하게 한 상태에서 global scaling의 시행 전후의 뇌 활성화 영상을 획득하였다. 결과 : 오른쪽 상지운동에 대한 기능영상에서 global scaling 효과를 고려하지 않은 경우와 고려한 경우의 뇌 활성화 영상의 차이는 크지 않았다 (p<0.000001). 청각기능 검사에서는 global scaling 효과를 고려한 경우에서 고려하지 않은 경우에 비해 뇌 활성화 영상이 훨씬 크게 나타났다 (p<0.05). 결론 : 국소적 BOLD 신호의 변화가 작은 기능영상 검사에서는 데이터 분석 시 global scaling이 뇌 활성화 결과에 큰 영향을 미칠 수 있으므로 주의가 요구된다.

• Korean Journal of Radiology
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• 제20권6호
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• pp.1001-1002
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• 2019