• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.1
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• pp.25-31
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• 2017

Liposomes are defined as spherical, self-closed structures formed by lipid bilayers containing aqueous phase. Most liposomes are composed of various amphipathic lipids such as phospholipids and cholesterol. We used amphipathic lipids (DPPC, DPPG) as liposome components and prepared around 100 nm liposomes by standard extrusion method. Nuclear/MR dual imaging agents based on liposome platform were prepared by adding radioactive $^{131}I$-HIB (hexadecyl-4-tributylstannylbenzoate) and Gd-DTPA into liposome bilayer and inside liposome, respectively. Gamma camera and MR imaging both showed signal increases in liver.

• Journal of Magnetics
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• v.17 no.3
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• pp.219-224
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• 2012

In the present study, changes in signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) of the diffusion-weighted images in the normal livers were investigated using changes in b values in 1.5 T MR (magnetic resonance) instruments. Respective diffusion-weighted images and ADC map images were obtained from 20 healthy individuals by increasing b values from 50 to 400 and 800 $s/mm^2$ using 1.5T MR scanner between January 2011 and November 2011. At each ADC map image obtained at each b value, ADCs in the right hepatic lobe, spleen and kidney were measured. As a result, ADCs of the right hepatic lobe, spleen and kidney have gradually decreased in the diffusion-weighted images in accordance with the reduced b value. This outcome may be used as preliminary data for applications to various abdominal diseases.

• Proceedings of the KSMRM Conference
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• 2000.11a
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• pp.33-33
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• 2000

• Proceedings of the KSMRM Conference
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• 1999.11a
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• pp.107-107
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• 1999

• Investigative Magnetic Resonance Imaging
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• v.23 no.1
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• pp.1-16
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• 2019

Dynamic contrast enhanced (DCE) magnetic resonance (MR) imaging plays an important role in non-invasive detection and characterization of primary and metastatic lesions in the liver. Recently, efforts have been made to improve spatial and temporal resolution of DCE liver MRI for arterial phase imaging. Review of recent publications related to arterial phase imaging of the liver indicates that there exist primarily two approaches: breath-hold and free-breathing. For breath-hold imaging, acquiring multiple arterial phase images in a breath-hold is the preferred approach over conventional single-phase imaging. For free-breathing imaging, a combination of three-dimensional (3D) stack-of-stars golden-angle sampling and compressed sensing parallel imaging reconstruction is one of emerging techniques. Self-gating can be used to decrease respiratory motion artifact. This article introduces recent MRI technologies relevant to hepatic arterial phase imaging, including differential subsampling with Cartesian ordering (DISCO), golden-angle radial sparse parallel (GRASP), and X-D GRASP. This article also describes techniques related to dynamic 3D image reconstruction of the liver from golden-angle stack-of-stars data.

• Korean Journal of Radiology
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• v.23 no.1
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• pp.13-29
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• 2022

Nonalcoholic fatty liver disease, characterized by excessive accumulation of fat in the liver, is the most common chronic liver disease worldwide. The current standard for the detection of hepatic steatosis is liver biopsy; however, it is limited by invasiveness and sampling errors. Accordingly, MR spectroscopy and proton density fat fraction obtained with MRI have been accepted as non-invasive modalities for quantifying hepatic steatosis. Recently, various quantitative ultrasonography techniques have been developed and validated for the quantification of hepatic steatosis. These techniques measure various acoustic parameters, including attenuation coefficient, backscatter coefficient and speckle statistics, speed of sound, and shear wave elastography metrics. In this article, we introduce several representative quantitative ultrasonography techniques and their diagnostic value for the detection of hepatic steatosis.

• The Journal of Pediatrics of Korean Medicine
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• v.22 no.1
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• pp.13-24
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• 2008

Objectives This study was designed to analyze the clinical studies on Mental retardation(MR) in traditional Chinese medicine(TCM). Methods For this study, we searched the clinical studies on MR, which had been published from 2003 to 2007, through web site CNKI(中國知識基礎設施工 http://www.cnki.net). There were 17 clinical studies and we focused on those studies. Results 1. In those Chinese studies, they used following words to describe Mental retardation; 小人弱智($xi\check{a}o\acute{e}rru\grave{o}zh\grave{i}$), 智能發育不全($zh\grave{i}n\acute{e}ngf\bar{a}y\grave{u}buqu\acute{a}n$), 智力低下($zh\grave{i}l\grave{i}d\bar{i}xi\grave{a}$), 精神發育遲滯($j\bar{i}ngsh\acute{e}f\bar{a}y\grave{u}ch\acute{i}zh\grave{i}$), 智能落后($zh\grave{i}n\acute{e}nglu\grave{o}h\grave{o}u$), 智能落后($zh\grave{i}n\acute{e}ngch\acute{i}hu\check{a}n$), 失天愚型患人($xi\bar{a}nti\bar{a}ny\acute{u}x\acute{i}nghu\grave{a}n'\acute{e}r$). 2. There were many kinds of TCM treatment methods for MR, such as herbal medicine, acupuncture, electroacupunture, acupoint injection, Chuna therapy, and special education. And those TCM treatments methods showed higher efficacies in the treatment of MR compared with Western medicine. 3. Mental retardation was related with the deficiency of heart, kidney, liver, spleen(心虛, 腎虛, 肝虛, 脾虛) and the pathological mechanism of Phlegm(絹) and Blood stasis(慫沂)in the studies about the Bian Zheng-the types of differential diagnosis- of MR. 4. Most of studies used Intelligence Quotient(IQ) to assess the efficacy of TCM treatment of MR. And the duration of treatment, the degree of illness, the age of patient, and the cause of illness affected the prognosis of MR. Conclusions These results suggest that traditional medicine could be one of the useful treatments on MR. And these results could be used in the clinical practices and studies on MR in Korea.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.43-45
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• 2018

Purpose In this study, we evaluated image by applying with and without point spread function algorithm(PSF) according to reconstruction type. Materials and Methods Biograph mMR (Siemens, Germany) was used as PET/MR scanner. For phantom study, we used NEMA IEC Body phantom maintaining radioactivity ratio (hotsphere:background = 8:1). To evaluate phantom image quality, percent contrast recovery and signal to noise ratio (SNR) were used by drawing ROI to 4 spheres. In clinical study, the 20 patients who underwent simultaneous PET/MR was selected and set the ROI at liver. we evaluated images as SNR. Results In the phantom results, The percent contrast recovery applying PSF algoritm was high 5 % compared to without PSF algoritm and SNR was also high 11 %. In the clinical study result, we confirmed that The SNR applying PSF algoritm was high 5 % compared to without PSF algoritm. Conclusion We need to simulate a lot of phantom study and clinical analysis to improve image quality for PET/MRI.

• Investigative Magnetic Resonance Imaging
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• v.4 no.1
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• pp.1-6
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• 2000

Protocol이란 Dorland의 의학사전에 의하면 "어떤 술기의 절차에 대한 명백하고 상세한 계획서(an explicit detiled plan of a procedure)"로 정의된다. 그래서 liver MR imaging protocol은 간에 발생한 병적 문제를 해결하기 위해서, 자기공명 영상술을 실시하는 구체적이고 세부적인 지침서를 말하게 된다. 그러나 현실적으로 병원에 따라 imaging protocol은 조금씩 다르다. 왜냐하면 자기공명영상 장비가 다르고, 적절한 펄스파형(pulse sequence)에 대한 통일된 안이 없기 때문이다. 자기공명영상술은 지금도 계속해서 빠르게 발전하고 있기 때문에, 현재 통용되는 영상 술기에 대한 자세한 지침은 곧 소용이 없게 된다. 그래서 본 소고에서는 간의 자기공명영상화의 병변의 특성화에 대한 기본적인 면에 더욱 중점을 두고 기술하고자 한다.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.145-145
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• 2006