• 대한의용생체공학회:의공학회지
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• 제19권1호
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• pp.91-100
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• 1998

자기 공명 영상에서 최근에 개발된 fast spin echo 영상법은 종래에 사용되었던 spin echo 영상법과 거의 같은 화질과 contrast를 제공하면서도 8-16배 이상 촬영 시간이 단축되어 임상적으로 많이 사용되는 촬영 방법 중의 하나로 자리 잡았다. 그러나 종래의 spin echo영상법과는 달리, 동시에 spin밀도 영상과T 강조 영상을 제공하는 dual echo 영상법은 fast spin echo의 경우, 촬영 시간이 2배로 늘어나기 때문에 그 중요한 장점을 잃어 버리게 되었다. 본 논문에서는 dual echo를 동시에 얻기 위한 현재의 fast spin echo 영상법의 이와 같은 단점을 해결하는 새로운 영상법을 제안한다. 새로운 영상법은 기존의 fast spin echo와 거의 같은 화질을 제공하면서도 dual echo 영상을 얻는데 추가 촬영 시간을 요구하지 않는다. 이를 입증하기 위하여 인체 실험을 수행하였고 그 결과를 기존의 방법으로 얻은 영상과 비교함으로써 그 유용성을 보인다.

• 대한방사성의약품학회지
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• 제6권2호
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• pp.177-181
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• 2020

Dual-modality imaging strategy using near-infrared fluorescence (FLI) and photoacoustic imaging (PAI) demands a suitable probe to enable dual-modular signal production. Herein, we demonstrate a synthetic protocol of small molecular dye for dual-modular FLI and PAI. A condensation reaction between squaric acid and carboxypentyl benzoindolium, and followed by basic hydrolysis to give the benzoindole derived squaraine (BSQ) dye in 49% yield. Next, the carboxylic acid group of BSQ was further functionalized with N-hydroxysuccinimide or azide group for an efficient conjugation with a targeting biomolecule. BSQ showed a maximum fluorescent emission at around 680 nm and the photoacoustic signal reached a maximum intensity at 680-700 nm. Based on these results, we conclude that BSQ analogs will be useful probes for dual-modular (FLI/PAI) imaging studies in animal models.

• Investigative Magnetic Resonance Imaging
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• 제1권1호
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• pp.75-78
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• 1997

인체의 하지 MR Angiography(MRA)를 위한 하지전용 dual birdcage RF 코일을 설계, 제작하였으며 Volunteer실험을 하여 그 유용성을 보였다. 제안된 코일은 인체의 하지 전체의 영상을 위한 코일로 허벅지로부터 종아리까지 전체를 두 번의 영상을 통해 cover하게 된다. 기존의 방식대로 한 개의 코일을 옮기며 두 번 촬영할 경우 코일을 도중에 옮기게 외어 다리를 움직일 수밖에 없어 두 set의 영상이 완전히 연결이 되지 않지만 제안된 코일의 경우 침대만 움직이게 되므로 이런 문제가 없게 된다. 제안된 코일의 성능은 Volunteer의 하지 MRI 및 MRA를 얻어 확인했으며 임상적으로 매우 유용한 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제24권9호
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• pp.1291-1299
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• 2014

Recently, multifunctional nanomaterials have been developed as nanotherapeutic agents for cellular imaging and targeted cancer treatment because of their ease of synthesis and low cytotoxicity. In this study, we developed a multifunctional, two-component nanorod consisting of gold (Au) and nickel (Ni) blocks that enables dual-fluorescence imaging and the targeted delivery of small interfering RNA (siRNA) to improve cancer treatment. Fluorescein isothiocyanate-labeled luteinizing hormone-releasing hormone (LHRH) peptides were attached to the surface of a Ni block via a histidine-tagged LHRH interaction to specifically bind to a breast cancer cell line, MCF-7. The Au block was modified with TAMRA-labeled thiolated siRNA in order to knock down the vascular endothelial growth factor protein to inhibit cancer growth. These two-component nanorods actively targeted and internalized into MCF-7 cells to induce apoptosis through RNA interference. This study demonstrates the feasibility of using two-component nanorods as a potential theranostic in breast cancer treatment, with capabilities in dual imaging and targeted gene delivery.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2011년도 춘계 학술발표회 및 심포지엄
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• pp.136-137
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• 2011

• 비파괴검사학회지
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• 제33권3호
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• pp.283-288
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• 2013

This paper describes development of a high speed Doppler OFDI system for non-invasive vascular imaging. Doppler OFDI (optical frequency domain imaging) is one of the phase-resolved second generation OCT (optical coherence tomography) techniques for high resolution imaging of moving elements in biological tissues. To achieve a phase-resolved imaging, two temporally separated measurements are required. In a conventional Doppler OCT, a pair of massively oversampled successive A-lines is used to minimize de-correlation noise at the expense of significant imaging speed reduction. To minimize a de-correlation noise between targeted two measurements without suffering from significant imaging speed reduction, several methods have been developed such as an optimized scanning pattern and polarization multiplexed dual beam scanning. This research represent novel imaging technique using frequency multiplexed dual beam illumination to measure exactly same position with aimed time interval. Developed system has been verified using a tissue phantom and mouse vessel imaging.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.294-298
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• 1997

In the magnetic resonance imaging, the fast spin echo imaging technique is a widely used clinical imaging method, since its scanning time is much shorter than the conventional spin echo imaging and it gives the almost same image quality. However, the fast spin echo technique has two times longer imaging time or the dual echo acquisition which can obtain a spin density image and a $T_2$-weighted image simultaneously. To overcome such a drawback, this paper proposes a new fast dual echo imaging technique which can give the same quality images at the single echo imaging time. The proposed technique reduces the imaging time by overlapping most of echo train data for each image reconstruction. In order to verify its validity and usability the human head experimental results which were obtained at the 0.3T permanent MRI system are presented.

• 대한방사성의약품학회지
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• 제3권1호
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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 Radiation Protection and Research
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• 제46권3호
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• pp.112-119
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• 2021

Background: This work aims to develop a new imaging system based on a pulse shape discrimination-capable Cs₂LiYCl₆:Ce (CLYC) scintillation detector combined with the rotational modulation collimator (RMC) technique for dual-particle imaging. Materials and Methods: In this study, a CLYC-based RMC system was designed based on Monte Carlo simulations, and a prototype was fabricated. Therein, a rotation control system was developed to rotate the RMC unit precisely, and a graphical user interface-based software was also developed to operate the data acquisition with RMC rotation. The RMC system was developed to allow combining various types of collimator masks and detectors interchangeably, making the imaging system more versatile for various applications and conditions. Results and Discussion: Operational performance of the fabricated system was studied by checking the accuracy and precision of the collimator rotation and obtaining modulation patterns from a gamma-ray source repeatedly. Conclusion: The prototype RMC system showed reliability in its mechanical properties and reproducibility in the acquisition of modulation patterns, and it will be further investigated for its dual-particle imaging capability with various complex radioactive source conditions.

• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2009년도 추계학술대회
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• pp.240-240
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• 2009