• 대한방사성의약품학회지
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• 제2권1호
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• pp.37-42
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• 2016

The translocator protein (TSPO) has attracted scientist's attention for Positron Emission Tomography (PET) imaging due to correlation with brain cancer, stroke, and neurodegeneration. Recently, GE-180, a novel tricyclic derivative has been developed as a new high affinity agent for the TSPO and evaluated to confirm a possibility for the TSPO ligand. In this highlight review, several studies for the novel TSPO radiotracer are described.

• 대한방사성의약품학회지
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• 제6권2호
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• pp.165-170
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• 2020

Histone Deacetylases (HDACs) are enzymes that have control gene expression regulation and cell state. In additions, inhibitions of HDACs are associated with growth arrest, differentiation, or apoptosis of tumor cell. Thus HDAC inhibition is one of the interesting biological targets. A variety of HDAC inhibitors has been developed by many scientists, and some of chemical structures related with HDAC inhibitors were modified to give radiolabeled HDAC inhibitors for positron emission tomography (PET) study. In this highlight review, the development of radiolabeled HDAC inhibitors for PET study are described.

• Journal of Korean Neurosurgical Society
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• 제49권5호
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• pp.278-283
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• 2011

Objective : The purpose of this study was to evaluate whether $^{18}F$-fluorodeoxyglucose positron emission tomography (FOG-PET) can be used to assess the therapeutic response of brain abscess. Methods : A study was conducted on 10 consecutive patients with brain abscess, Magnetic resonance imaging (MRI) with diffuse-weighted imaging (DWI) was performed at 3 and 6 weeks after surgical treatment and intravenous antibiotics therapy and FOG-PET at 6 weeks after treatment. The extent of the abscess, signal changes on MRI, and FOG-PET standardized uptake values were analyzed and correlated with the response to therapy. Results : Aspiration or craniotomy with excision of the abscess followed by intravenous antibiotics for 6-8 weeks resulted in good recovery with no recurrence. In 10 patients, two had low signal intensity on the DWI; one had no uptake on FOG-PET imaging after 6 weeks antibiotics and discontinued intravenous treatment, but the other patient had diffuse, increased uptake on FOG-PET imaging after 6 weeks antibiotics and underwent an additional 2 weeks of intravenous antibiotics. The remaining eight patients had high signals on the DWI. Four had no uptake on FOG-PET imaging and the treatment period varied from 6 to 8 weeks (mean, 6.75 weeks). Among the other four patients, FOG was accumulated in a diffuse or local area corresponding to a high signal area within the DWI and 2 weeks of intravenous antibiotics was added. Conclusion : MRI plus FOG-PET improved the accuracy of assessing therapeutic responses to antibiotics treatment of brain abscess and aided in optimizing therapy.

• Radiation Oncology Journal
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• 제29권3호
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• pp.214-217
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• 2011

To avoid improper tumor volume contouring in radiation therapy (RT) and other invasive procedures, we report a case of uterine adenomyosis showing increased $^{18}F$-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET)/computed tomography (CT) mimicking malignant tumor in a 44-year-old woman during concurrent chemoradiation therapy (CCRT) for uterine cervical cancer. The adenomyosis was not associated with her menstrual cycle or with normal endometrium uptake, and it resolved one month after completion of RT. This case indicates that uterine adenomyosis in a premenopausal woman may show false positive uptake of $^{18}FDG$-PET/CT associated with CCRT.

• 대한방사선기술학회지:방사선기술과학
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• 제39권3호
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• pp.369-376
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• 2016

양전자방출단영상(Positron Emission Tomography, PET)은 여러 화합물과 방사성 동위원소를 결합하여 인체 내에 주입하여 인체 내의 대사율을 정량적으로 측정할 수 있는 핵의학적 검사이다. 특히, 암 조직에서 포도당 대사가 증가되는 현상을 $^{18}F$-FDG(Fluorodeoxyglucose)를 사용하여 널리 암 진단에 활용하며, 현대에서 발병 빈도가 높은 뇌질환 중 치매 및 파킨슨 진단에도 높은 유용성을 보인다는 연구가 다수 진행되었다. 이러한 현재의 정적 정보에 시간의 동적 정보를 포함하는 동적 양전자방출단층영상(dynamic PET, dPET)을 이용할 경우, 진단을 위한 추가적인 정보가 제공되므로 진단의 정확도 향상에 기여할 수 있다. 이러한 이유로 임상 연구자 및 방사선사의 큰 관심을 받고 있으나 연구를 진행하기 위해 손쉽게 사용 가능한 도구가 부족한 실정이며, 다양하고 복잡한 수학적 알고리즘(algorithm)이나 프로그래밍(programming) 기술이 부족할 경우 연구의 활성화를 방해하는 높은 진입장벽으로 존재하게 되므로, 본 연구에서는 dPET 연구의 활성화와 손쉬운 사용을 위해서 MATLAB을 이용하여 그래픽 유저(GUI) 기반으로 하여 무료 소프트웨어를 개발하였으며, 개발된 소프트웨어인 DIA-Tool(Dynamic Image analysis-Tool)은 복잡한 수학적 영상 분석 알고리즘을 누구나 손쉽게 사용할 수 있도록 설계되었다. 향후, 많은 임상 연구자들이 DIA-Tool을 이용하여 국내의 dPET 연구 발전에 큰 도움이 될 것이라 기대된다.

• 핵의학기술
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• 제28권1호
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• pp.35-40
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• 2024

Purpose: To improve the image quality in positron emission tomography (PET), the attenuation correction technique based on the computed tomography (CT) data is important process. However, the artifact is caused by metal material during PET/CT scan, and the image quality is degraded. Therefore, the purpose of this study was to evaluate image quality according to with and without iterative metal artifact reduction (iMAR) algorithm using customized 3D printing phantom. Materials and Methods: The Hoffman and Derenzo phantoms were designed. To protect the gamma ray transmission and express the metal portion, lead substance was located to the surface. The SiPM based PET/CT was used for acquisition of PET images according to application with and without iMAR algorithm. The quantitative methods were used by signal to noise ratio (SNR), coefficient of variation (COV), and contrast to noise ratio (CNR). Results and Discussion: The results shows that the image quality applying iMAR algorithm was higher 1.15, 1.19, and 1.11 times than image quality without iMAR algorithm for SNR, COV, and CNR. Conclusion: In conclusion, the iMAR algorithm was useful for improvement of image quality by reducing the metal artifact lesion.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.506-510
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• 2004

There have been intensive studies concerning $[^{11}F]$choline ($[^{11}F]$methyldimethyl( ${\beta}$ -hydroxyethyl) ammonium) (1) which is known as a very effective tracer in imaging various human tumors localized in brain, lung, esophagus, rectum, prostate and urinary bladder using Positron Emission Tomography (PET) and there is increasing interest in $^{18}F$ labelled choline (2) and proved to be useful to visualize prostate cancer. We have prepared six $^{18}F$ labelled alkyl choline derivatives (3a-3c, 4a-4c) from ditosylated and dibrominated alkanes in moderate yields. The six alkyl tosylate or bromate ammonium salts have been synthesized as precursors. Radiofluorination was achieved by the treatment of precursors with $^{18}F$ - in the presence of Kryptofix-2.2.2.. The labeling yields varied ranging from 7 to 25%.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (2)
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• pp.301-303
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• 2002

Subspace analysis is a popular method for multivariate data analysis and is closely related to factor analysis and principal component analysis (PCA). In the context of image processing (especially positron emission tomography), all data points are nonnegative and it is expected that both basis images and factors are nonnegative in order to obtain reasonable result. In this paper We present a sequential EM algorithm for rectified subspace analysis (subspace in nonnegativity constraint) and apply it to dynamic PET image analysis. Experimental results show that our proposed method is useful in dynamic PET image analysis.

• 대한방사성의약품학회지
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• 제2권1호
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• pp.3-8
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• 2016

Molecular imaging technologies have been used to provide a new pathway for therapies and diagnosis of human disease. Especially, imaging probes have been much development in the molecular imaging field. Combining imaging probes for positron emission tomography (PET) and magnetic resonance imaging (MRI) have suggested the potential of multiple methods in living body. This review discusses the cancer or lymph node-targeting probes that are suitable for PET/MRI based diagnosis.

• 대한두경부종양학회:학술대회논문집
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• 대한두경부종양학회 1998년도 제3차 춘계심포지움
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• pp.112-114
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• 1998