• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.37-37
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• 2003

To assess the merits and demerits of postcontrast fat-suppressed (FS) brain MR imaging in children in the evaluation of various enhancing lesions, compared with postcontrast conventional or Magnetization Transfer (MT) imaging. 대상 및 방법： We reviewed patients with enhancing lesion on brain MR imaging who underwent both FS imaging and one of conventional or MT imaging as a postcontrast T1-weighted brain MR imaging. Inclusion criteria of our study were as follows： MR studies should be peformed within one-year interval and showed no significant interval change of imaging findings. Thirty-four patients (21 male, 13 female; mean age, 8 years) with 43 enhancing lesions (19 intra-axial, 19 extra-axial, and 5 orbital location) were included in this study, Twenty-one pairs of FS and conventional imaging, and 15 pairs of FS and MT imaging were available. Two radiologists visually assessed the lesion conspicuity and the presence of flow or susceptibility artifacts in a total of 36 pairs of MR imaging by consensus. For 21 measurable lesions (19 pairs of FS and conventional imaging, 5 pairs of FS and MR imaging), contrast ratio between the lesion and the normal brain( ［SIlesion-SIwater］/[SInormal brain-SIwater]) were calculated and compared.

• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.131-139
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• 2004

Small animal models are extensively utilized in the study of biomedical sciences. Current animal experiments and analysis are largely restricted to in vitro measurements and need to sacrifice animals to perform tissue or molecular analysis. This prevents researchers from observing in vivo the natural evolution of the process under study. Imaging techniques can provide repeatedly in vivo anatomic and molecular information noninvasively. Small animal imaging systems have been developed to assess biological process in experimental animals and increasingly employed in the field of molecular imaging studies. This review outlines the current developments in nuclear medicine imaging instrumentations including fused multi-modality imaging systems for small animal imaging.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.223-229
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• 2012

Clinical and preclinical in vivo immune cell imaging approaches have been used to study immune cell proliferation, apoptosis and interaction at the microscopic (intra-vital imaging) and macroscopic (whole-body imaging) level by use of ex vivo or in vivo labeling method. A series of imaging techniques ranging from non-radiation based techniques such as optical imaging, MRI, and ultrasound to radiation based CT/nuclear imaging can be used for in vivo immune cell tracking. These imaging modalities highlight the intrinsic behavior of different immune cell populations in physiological context. Fluorescent, radioactive or paramagnetic probes can be used in direct labeling protocols to monitor the specific cell population. Reporter genes can also be used for genetic, indirect labeling protocols to track the fate of a given cell subpopulation in vivo. In this review, we summarized several methods dealing with dendritic cell, macrophage, and T lymphocyte specifically labeled for different macroscopic whole-body imaging techniques both for the study of their physiological function and in the context of immunotherapy to exploit imaging-derived information and immune-based treatments.

• Journal of the Korean Society of Radiology
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• v.6 no.5
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• pp.409-414
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• 2012

This study acquired molecular lmaging using nano-contrast agents, and the general condition of the same image acquisition to analyze the difference between molecular imaging and general imaging, two images are converted into DWT (Discrete Wavelet Transform). Nano-contrast agent imaging using MRI and molecular imaging using PET study of molecular imaging technology mainstream. DWT analysis of the same lesions using MRI imaging and molecular imaging block lesions are present in the lesions, illustrating the value of a high-frequency feature both highly general imaging and molecular imaging could know that. The high frequency region of the feature extraction values appear higher molecular imaging.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.2
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• pp.145-152
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• 2008

Nuclear medicine imaging has an unique advantage of absolute quantitation of radioactivity concentration in body. Tracer kinetic analysis has been known as an useful investigation methods in quantitative study of in-vivo physiological function. The use of nuclear medicine imaging and kinetic analysis together can provide more useful and powerful intuition in understanding biochemical and molecular phenomena in body. There have been many development and improvement in kinetic analysis methodologies, but the conventional basic concept of kinetic analysis is still essential and required for further advanced study using new radiopharmaceuticals and hybrid molecular imaging techniques. In this paper, the basic theory of kinetic analysis and imaging techniques for suppressing noise were summarized.

• Current Optics and Photonics
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• v.3 no.4
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• pp.329-335
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• 2019

Wide FOV imaging systems are important for acquiring rich visual information. A conventional catadioptric imaging system deploys a camera in front of a curved mirror to acquire a wide FOV image. This is a cumbersome setup and causes unnecessary occlusions in the acquired image. In order to reduce both the burden of the camera deployment and the occlusions in the images, this study uses a secondary planar mirror in the catadioptric imaging system. A compact design of the catadioptric imaging system and a condition for the position of the secondary planar mirror to satisfy the central imaging are presented. The image acquisition model of the catadioptric imaging system with a secondary planar mirror is discussed based on the principles of geometric optics in this study. As a backward mapping, the acquired image is restored to a distortion-free image in the experiments.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1259-1265
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• 2021

In the present study, a large-area hybrid gamma imaging system was designed by adopting coded aperture imaging on the basis of a large-area Compton camera to achieve high imaging performance throughout a broad energy range (100-2000 keV). The system consisting of a tungsten coded aperture mask and monolithic NaI(Tl) scintillation detectors was designed through a series of Geant4 Monte Carlo radiation transport simulations, in consideration of both imaging sensitivity and imaging resolution. Then, the performance of the system was predicted by Geant4 Monte Carlo simulations for point sources under various conditions. Our simulation results show that the system provides very high imaging sensitivity (i.e., low values for minimum detectable activity, MDA), thus allowing for imaging of low-activity sources at distances impossible with coded aperture imaging or Compton imaging alone. In addition, the imaging resolution of the system was found to be high (i.e., around 6°) over the broad energy range of 59.5-1330 keV.

• Korean Journal of Radiology
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• v.20 no.1
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• pp.18-33
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• 2019

In this study, we summarize the clinical role of magnetic resonance imaging (MRI) in the diagnosis of patients with malignant uterine neoplasms, including leiomyosarcoma, endometrial stromal sarcoma, adenosarcoma, uterine carcinosarcoma, and endometrial cancer, with emphasis on the challenges and disadvantages. MRI plays an essential role in patients with uterine malignancy, for the purpose of tumor detection, primary staging, and treatment planning. MRI has advanced in scope beyond the visualization of the many aspects of anatomical structures, including diffusion-weighted imaging, dynamic contrast enhancement-MRI, and magnetic resonance spectroscopy. Emerging technologies coupled with the use of artificial intelligence in MRI are expected to lead to progressive improvement in case management of malignant uterine neoplasms.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.3
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• pp.165-173
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• 2009

Nuclear cardiology in Korea is less active, compared to nuclear oncology, but it has been specialized and ramified. Lately, sophisticated nuclear cardiac imaging methods provide more convenience for patients. It is necessary to accurately estimate the recent progress in the imaging devices for nuclear cardiology. Myocardial perfusion imaging is a well established study to evaluate heart function. Myocardial perfusion SPECT and PET have been used for assessment of coronary artery disease with various radiopharmaceuticals. And of late, the development of advanced imaging devices - multi-pinhole technique and high definition imaging technique - and software made the scanning time shorter and expanded the application field. Therefore, it is required to review the nuclear cardiology hardware/software for the clinical practice and research. In this review, the characteristics about recently-developed SPECT/PET and software for nuclear cardiology are described. It is hoped that this information would contribute to improving the activity of nuclear cardiac research in Korea where the research for the fusion imaging combining a and nuclear imaging is drawing more attention.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.3
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• pp.303-310
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• 2011

Purpose : This study examined the feedback effect of real-time ultrasound imaging on the thickness of transversus abdominis(TrA), internal abdominal oblique(IO) and external abdominal oblique(EO) during abdominal hollowing exercise(AHE) in crook lying. Methods : We performed this study on 30 healthy men who voluntarily consented to participate in this study after listening to its purpose and method. All subject were divided into an experimental group(n=15) with using the real-time ultrasound imaging feedback(RUIF) and a control group(n=15) without the RUIF The thickness changes between rest and AHE were compared between the two groups in crook lying. Results : The difference in TrA and EO thickness changes between the groups were significant in crook lying (p<0.05). Conclusion : The group with using real-time ultrasound imaging feedback showed a higher increase in the thickness of TrA than the other group without real-time ultrasound imaging feedback. And the thickness of EO in the group with using real-time ultrasound imaging feedback decreased than the other group without real-time ultrasound imaging feedback. If the muscle thickness can be regarded as an indicator of muscle activity, RUIF will be helpful for inducing the independent activity of TrA by reducing the activities of abdominal muscles such as EO.