• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.32-39
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• 2005

Introduction: Currently, F-18 fluorodeoxyglucose positron emission tomography scans (FDG-PET) has been investigated in soft tissue tumor especially for tumor detection and noninvasive grading. However, the validity and the efficacy of FDG-PET are still unclear in clinical evaluation. The purpose of this study is to determine the efficacy of FDG-PET in compared to conventional diagnostic imaging studies currently used in the soft tissue tumor. Methods: Between March 2001 and March 2002, 29 patients (sixteen males, thirteen females, mean age, 47 years; a range from 4 to 73) diagnosed with soft tissue tumor were evaluated by both conventional diagnostic imaging and FDG-PET. Valid reference test of the local lesion was the histopathologic diagnosis, which was measured in all patients. The suspecting metastasis in the imaging studies was validated by pathology or follow up imaging for at least 6 months. Each imaging diagnosis was made independently. The accuracy of each diagnostic method was evaluated. The incremental cost accuracy ratio was determined in each diagnostic method. Results: For detection of local lesion, sensitivity, specificity, and accuracy for MRI and FDGPET scans were 91%, 57%, 83% and 95%, 43%, 83% respectively. For detection of distant lesion, sensitivity, specificity, accuracy for conventional diagnostic methods and FDG-PET scans were 77%, 89%, 87% and 92%, 94%, 93% respectively. The incremental cost accuracy ratio (ICAR) of FDG-PET for detection of distant lesion was 145,000won/%. According to ICAR for each tumor grade, PET strategy is most cost-effective at high grade tumors. Conclusions: For detection of local lesion such as recurrence or remnant tumor, FDG-PET scan was not more accurate than MRI. However, It was more accurate for detection of metastatic lesion than conventional methods. For detection of high grade tumor, PET was most costeffective than for detection of lower grade tumor.

• Korean Journal of Radiology
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• v.22 no.12
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• pp.1938-1945
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• 2021

Breast radiologists are increasingly seeing patients with axillary adenopathy related to COVID-19 vaccination. Vaccination can cause levels I-III axillary as well as cervical lymphadenopathy. Appropriate management of vaccine-related adenopathy may vary depending on clinical context. In patients with current or past history of malignancy, vaccine-related adenopathy can be indistinguishable from nodal metastasis. This article presents imaging findings of oncology patients with adenopathy seen in the axilla or neck on cross-sectional imaging (breast MRI, CT, or PET-CT) after COVID-19 vaccination. Management approach and rationale is discussed, along with consideration on strategies to minimize false positives in vaccinated cancer patients. Time interval between vaccination and adenopathy seen on breast MRI, CT, or PET-CT is also reported.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.2
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• pp.98-111
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• 2008

This review introduces advances in clinical and pre-clinical single photon emission computed tomography (SPECT) and positron emission tomography (PET) providing noninvasive functional images of biological processes. Development of new collimation techniques such as multi-pinhole and slit-slat collimators permits the improvement of system spatial resolution and sensitivity of SPECT. Application specific SPECT systems using smaller and compact solid-state detector have been customized for myocardial perfusion imaging with higher performance. Combined SPECT/CT providing improved diagnostic and functional capabilities has been introduced. Advances in PET and CT instrumentation have been incorporated in the PET/CT design that provide the metabolic information from PET superimposed on the anatomic information from CT. Improvements in the sensitivity of PET have achieved by the fully 3D acquisition with no septa and the extension of axial field-of-view. With the development of faster scintillation crystals and electronics, time-of-flight (TOF) PET is now commercially available allowing the increase in the signal-to-noise ratio by incorporation of TOF information into the PET reconstruction process. Hybrid PET/SPECT/CT systems has become commercially available for molecular imaging in small animal models. The pre-clinical systems have improved spatial resolution using depth-of-interaction measurement and new collimators. The recent works on solid state detector and dual modality nuclear medicine instrumentations incorporating MRI and optical imagers will also be discussed.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.1
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• pp.9-14
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• 2015

Hypoxia has been shown in many tumors because of a reduced oxygen condition. A useful approach to detect hypoxia is to use molecular imaging. Positron emission tomography (PET), one of the biomedical molecular imaging tools, is the most common non-invasive technique for providing information about physiological and biological events such as diseases. In order to use the PET technique for healthcare, promising molecular probes such as PET tracers required. [$^{18}F$]Fluoromisonidazole ([$^{18}F$]FMISO) is the most widely used in PET tracers for hypoxia. In this review, major developments of the synthetic method of [$^{18}F$]FMISO are discussed.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.2
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• pp.71-77
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• 2007

Advance of neuroimaging technique has greatly influenced recent brain research field. Among various neuroimaging modalities, positron emission tomography has played a key role in molecular neuroimaging though functional MRI has taken over its role in the cognitive neuroscience. As the analysis technique for PET data is more sophisticated, the complexity of the method is more increasing. Despite the wide usage of the neuroimaging techniques, the assumption and limitation of procedures have not often been dealt with for the clinician and researchers, which might be critical for reliability and interpretation of the results. In the current paper, steps of voxel-based statistical analysis of PET including preprocessing, intensity normalization, spatial normalization, and partial volume correction will be revisited in terms of the principles and limitations. Additionally, new image analysis techniques such as surface-based PET analysis, correlational analysis and multimodal imaging by combining PET and DTI, PET and TMS or EEG will also be discussed.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.149-152
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• 2008

Nonmelanomatous skin cancer includes basal cell carcinoma, squamous cell carcinoma, merkel cell carcinoma and dermatofibrosarcoma protuberance. So far, there have been a few reports that $^{18}F-FDG$ PET was useful in the evaluation of metastasis and therapeutic response in nonmelanomatous skin cancer, however, those are very weak evidences. Therefore, further studies on the usefulness of $^{18}F-FDG$ PET in nonmelanomatous skin cancer are required.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.2
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• pp.123-129
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• 2015

$^{64}Cu$-labeled diacetyl-bis($N^4$-methylthiosemicarbazone) is a promising agent for internal radiation therapy and imaging of hypoxic tissues. In the study, we confirmed hypoxia regions in VX2 tumor implanted rabbits with injection $^{64}Cu$-ATSM and $^{18}F$-FDG using positron emission tomography (PET)/computed tomography (CT). PET images with $^{18}F$-FDG and $^{64}Cu$-ATSM were obtained for 40 min by dynamic scan and additional delayed PET images of $^{64}Cu$-ATSM the acquired up to 48 hours. Correlation between intratumoral $O_2$ level and $^{64}Cu$-ATSM PET image was analyzed. $^{64}Cu$-ATSM and $^{18}F$-FDG were intravenously co-injected and the tumor was dissected and cut into slices for a dual-tracer autoradiographic analysis. In the PET imaging, $^{64}Cu$-ATSM in VX2 tumors displayed a specific uptake in hypoxic region for48 h. The uptake pattern of $^{64}Cu$-ATSM in VX2 tumor at 24 and 48 h did not match to the $^{18}F$-FDG. Through ROI analysis, in the early phase (dynamic scan), $^{18}F$-FDG has positive correlation with $^{64}Cu$-ATSM but late phase (24 and 48 h) of the $^{64}Cu$-ATSM showed negative correlation with $^{18}F$-FDG. High uptake of $^{64}Cu$-ATSM in hypoxic region was responded with significant decrease of oxygen pressure, which confirmed by $^{64}Cu$-ATSM PET imaging and autoradiographic analysis. In conclusion, $^{64}Cu$-ATSM can utilize for specific targeting of hypoxic region in tumor, and discrimination between necrotic- and viable hypoxic tissue.

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.53-63
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• 2002

FDG PET is a functional imaging modality whose ability to detect lesions is directly based on a change of the glycolytic metabolism of targeted tissues, may be advantageous over other techniques. Combined with excellent image qualify, high spatial resolution, and whole body imaging capability, it has become popular as a new approach in the evaluation of patients with various malignancies. Initial staging of nodal and extranodal lymphoma using FDG PET has been proven to be at least equal or superior to conventional imaging modalities. For the assessment of treatment responsiveness, FDG PET has a major impact on the management of patients in differentiating residual lymphoma from treatment related benign changes. Residual FDG uptake after the completion of chemotherapy is a good predictor of early relapse. However, it seems that the absence of FDG uptake in tumor mass may not exclude minimal residual disease causing later relapse. In the early evaluation of treatment response only after a few cycles of chemotherapy, FDG PET may have a promising role in identifying non-responders who could benefit from a different treatment strategy. At present, FDG PET appears to be the cost-effective, diagnostic modality of choice in the management of lymphoma patients. The role of FDG PET based-systems in terms of affecting long-term prognosis and survival benefit should be further elucidated in future prospective studios.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.6
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• pp.279-292
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• 2006

Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of biomedical research. These tools have been validated recently in variety of research models, and have born shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene delivery and/or expression. This article reviews the use of PET technologies as they have been used in imaging biological processes for molecular imaging applications. The studies published to date demonstrate that noninvasive imaging tools will help to accelerate pre-clinical model validation as well as allow for clinical monitoring of human diseases.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.1
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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.