• Journal of Chest Surgery
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• v.36 no.2
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• pp.79-85
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• 2003

Diagnosing and determining the stage of lung cancer by means of positron emission tomography (PET) ha.. been proven valuable because of the limitations of diagnosis by computed tomography (CT). We compared the efficacy of PET with that of CT in diagnosing pulmonary tumor and staging of lung cancer Material and Method: We performed F-18 FDG PET to determine the malignancy and the staging on patients who have been suspicious or were diagnosed as lung cancer by chest X-ray and CT. The findings of PET and of CT of 41 patients (male, 29: female, 12: mean age, 59) were compared with pathologic findings obtained from a mediastinoscopy and thoracotomy. Result: Out of 41 patients, 35 patients had malignant lesions (squamous cell carcinonla 19 cases, adenocarcinoma 14 cases, adenosquamous cell carcinoma 2 cases) and 6 patients had benign lesions. Diagnosing of lung cancer, the sensitivity, specificity and accuracy of CT and PET were the same for two method and the numbers were 100%, 50%, and 92.7% respectively. Eighteen LN groups out of 108 mediastinal LN groups who recieved histologic examination proved to be malignant. Pathologic lymph node (LN) stage was N0-Nl 31 cases, N2 8 cases, N3 2 cases. The correct identification of the nodal staging with CT, PET scans were 31 cases (75.6%), 28 cases (68.3%) respectively. The LN group was underestimated in each 6 cases of CT and PET. In 4 cases of CT and 7 cases of PET, they were overestimated in compare to histologic diagnosis. In the detection of mediastinal LN groups invasion, the sensitivity, specificity and accuracy of CT were 39.8 %, 93.3 %, and 84.3 % respectively. For PET, they were 61.1 %, 90.0 %, and 85.2 %. When two methods considered together (CT+PET), they were increased to 77.8 %, 93.3 %, and 90.7 % respectively. Conclusion: PET appears to be similar to CT in the diagnosis and the nodal taging of pulmonary tumor. Two tests may stage patients with lung cancer more accurately than CT alone.

• Journal of the Society of Disaster Information
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• v.13 no.1
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• pp.96-105
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• 2017

Global warming, mainly caused by CO2, is one of the on­going cataclysms of the human race. The nation­wide policy to reduce greenhouse gases (GHG) has been enforced, for which it is crucial to estimate reliable GHG emissions. The unit load of road­section CO2 emission (URSCE) is a prerequisite for the evaluation of GHG emissions from road mobile source, and it is mainly computed using vehicular velocity source. Unfortunately, there is real­world limitations to collect and analyse representative speed data for nation­wide road network. To tackle this problem, a method for the evaluation of URSCE, proposed in this study, is based on a disaggregated way using big GPS vehicle data. The method yields more accurate URSCE than an current aggregated data based approach and can be directly employed for nation­wide road systems.

• Tuberculosis and Respiratory Diseases
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• v.64 no.2
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• pp.133-137
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• 2008

Pulmonary paragonimiasis continues to be a diagnostically challenging parasitic disease, despite a drastically decreased prevalence in South Korea during the past decade. Pulmonary paragonimiasis is characterized by fever, chest pain, and chronic cough with hemoptysis. Numerous radiographic and computed tomographic findings including the presence of pneumothorax, pleural effusion, and parenchymal lesions such as nodular or infiltrative opacities have been reported. The clinical and radiological manifestations of paragonimiasis can resemble those of lung cancer, tuberculosis or a metastatic malignancy. Furthermore, this disease can mimic lung cancer as seen on $^{18}F$-fluorodeoxyglucose positron emission tomography (FDG-PET). We report a case of pulmonary paragonimiasis in a 48-year old man that presented with a solitary pulmonary nodule and was suspected as a lung cancer based on FDG-PET imaging.

• Journal of Yeungnam Medical Science
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• v.34 no.2
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• pp.279-284
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• 2017

Pulmonary artery sarcoma (PAS) is a rare and fatal disease that often mimics chronic thromboembolic pulmonary hypertension (CTEPH); therefore, diagnosis of PAS is often delayed. Herein, a healthy 74-year-old man was presented with a 4-month history of dyspnea. Chest computed tomography showed wall thickening and stenosis in the main pulmonary artery as well as in both proximal pulmonary arteries. In order to differentiate between unusual CTEPH, vasculitis, and PAS, we performed right heart catheterization and pulmonary angiography. The mean pulmonary arterial pressure was 21 mmHg, and there was severe pulmonary artery stenosis. Thrombi on the pulmonary arterial wall lesions were observed in intravascular ultrasound and optical coherence tomography. Furthermore, the patient had a history of deep vein thrombosis. Therefore, we diagnosed unusual CTEPH. After 6 months of rivaroxaban anticoagulation therapy, a chest X-ray revealed a left lower lobe lung mass, and a positron emission tomography later showed hypermetabolic lesions in the main pulmonary artery wall, in both pulmonary arteries walls, in the lung parenchyma, and in the bones. A biopsy of the right proximal humerus lesion revealed undifferentiated intimal sarcoma. Pulmonary sarcoma is rare, but should be considered when differentially diagnosing main pulmonary artery wall thickening and stenosis. A positron emission tomography may aid in this diagnosis.

• Brain Tumor Research and Treatment
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• v.6 no.2
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• pp.47-53
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• 2018

Brain tumors represent a diverse spectrum of histology, biology, prognosis, and treatment options. Although MRI remains the gold standard for morphological tumor characterization, positron emission tomography (PET) can play a critical role in evaluating disease status. This article focuses on the use of PET with radiolabeled glucose and amino acid analogs to aid in the diagnosis of tumors and differentiate between recurrent tumors and radiation necrosis. The most widely used tracer is $^{18}F$-fluorodeoxyglucose (FDG). Although the intensity of FDG uptake is clearly associated with tumor grade, the exact role of FDG PET imaging remains debatable. Additionally, high uptake of FDG in normal grey matter limits its use in some low-grade tumors that may not be visualized. Because of their potential to overcome the limitation of FDG PET of brain tumors, $^{11}C$-methionine and $^{18}F$-3,4-dihydroxyphenylalanine (FDOPA) have been proposed. Low accumulation of amino acid tracers in normal brains allows the detection of low-grade gliomas and facilitates more precise tumor delineation. These amino acid tracers have higher sensitivity and specificity for detecting brain tumors and differentiating recurrent tumors from post-therapeutic changes. FDG and amino acid tracers may be complementary, and both may be required for assessment of an individual patient. Additional tracers for brain tumor imaging are currently under development. Combinations of different tracers might provide more in-depth information about tumor characteristics, and current limitations may thus be overcome in the near future. PET with various tracers including FDG, $^{11}C$-methionine, and FDOPA has improved the management of patients with brain tumors. To evaluate the exact value of PET, however, additional prospective large sample studies are needed.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.7 no.2
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• pp.99-103
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• 2021

In this study, the initial in vivo pharmacokinetic changes according to the routes of drug administration were investigated using bioimaging techniques. The purpose of this study was to quantify the degree of distribution of each major organ in normal mice over time by acquiring Positron Emission Tomography/Computed Tomography images while administering routes F-18 fluorodeoxyglucose such as intravenous, intraperitoneal and per oral, a representative diagnostic radiopharmaceutical. Dynamic Positron Emission Tomography images were acquired for 90 minutes after drug administration. Radioactivity uptake was calculated for major organs using the PMOD program. In the case of intravenous administration, it was confirmed that it spread quickly and evenly to major organs. Compared to intravenous administration, intraperitoneal administration was about three times more absorbed and distributed in the liver and intestine, and it was showed that the amount excreted through the bladder was more than twice. In the case of oral administration, most stayed in the stomach, and it was showed that it spread slowly throughout the body. In comparison with intravenous administration, it was presented that the distribution of kidneys was more than 9 times and the distribution of bladder was 66% lower. Since there is a difference in the initial in vivo distribution and excretion of each administration method, we confirmed that the determination of the administration route is important for in vivo imaging evaluation of new drug candidates.

• Journal of the Korea Society of Computer and Information
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• v.29 no.6
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• pp.23-29
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• 2024

In this paper, we propose a fast GPU-based method for representing pore flow, absorption, emission, and diffusion effects represented by cloth-liquid interactions using smoothed particle hydrodynamics (SPH), a particle-based fluid solver: 1) a unified framework for GPU-based representation of various physical effects represented by cloth-liquid interactions; 2) a method for efficiently calculating the saturation of a node based on SPH and transferring it to the surrounding porous particles; 3) a method for improving the stability based on Darcy's law to reliably calculate the direction of fluid absorption and release; 4) a method for controlling the amount of fluid absorbed by the porous particles according to the direction of flow; and finally, 5) a method for releasing the SPH particles without exceeding their maximum mass. The main advantage of the proposed method is that all computations are computed and run on the GPU, allowing us to quickly model porous materials, porous flows, absorption, reflection, diffusion, etc. represented by the interaction of cloth and fluid.

• Electronics and Telecommunications Trends
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• v.29 no.5
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• pp.96-104
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• 2014

1895년 독일 과학자 Wilhelm Roentgen 박사가 X-ray를 발견하고 미국의 Herman Carr가 MRI(Magnetic Resonance Imaging)의 기본 원리를 개발하여 발표한 이후 전자기장을 이용한 비침습적 의료영상 이미지 시스템은 놀라운 발전을 계속하여 왔다. 하지만, X-ray, CT(Computed Tomography), PET(Positron Emission Tomography)의 경우는 방사능의 사용과 조영제의 독성이라는 문제로 인하여 안전성에 대한 계속적인 문제를 야기해왔고 상대적으로 안전성이 입증된 MRI의 경우는 장비 자체 및 운용비가 일반화되기에는 고가여서 우리나라를 포함한 선진국에서도 아주 제한적으로 운영되고 있는 실정이다. 따라서, 세계적으로도 이러한 문제를 해결하기 위하여 안전하면서도 상대적으로 저렴한 비용으로 운용이 가능한 의료영상장비를 개발하기 위하여 많은 노력들이 경주되고 있어 관련 연구동향 및 산업화 동향을 소개하고자 한다.

• Radiation Oncology Journal
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• v.33 no.3
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• pp.161-171
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• 2015

Image-guided radiation therapy (IGRT) is a process of incorporating imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), Positron emission tomography (PET), and ultrasound (US) during radiation therapy (RT) to improve treatment accuracy. It allows real-time or near real-time visualization of anatomical information to ensure that the target is in its position as planned. In addition, changes in tumor volume and location due to organ motion during treatment can be also compensated. IGRT has been gaining popularity and acceptance rapidly in RT over the past 10 years, and many published data have been reported on prostate, bladder, head and neck, and gastrointestinal cancers. However, the role of IGRT in lymphoma management is not well defined as there are only very limited published data currently available. The scope of this paper is to review the current use of IGRT in the management of lymphoma. The technical and clinical aspects of IGRT, lymphoma imaging studies, the current role of IGRT in lymphoma management and future directions will be discussed.

• The Korean Journal of Nuclear Medicine
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• v.32 no.5
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• pp.433-435
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• 1998

Recent progress of technology permits us to assess ventricular function and wall motion as well as myocardial perfusion using electrocardiographic gated myocardial perfusion single photon emission computed tomography (GM-SPECT). It is interesting that echocardiography and magnetic resonance imaging are moving in the same direction with the use of contrast medium to assess myocardial perfusion. A valid fundamental basis for a new technology is essential for a successful competition. Lee et al. report in this issue the reproducibility of serial measurement of left ventricular function including systolic wall thickening using a novel statistical method. It has important implications such as nitroglycerin or dobutamine application during GM-SPECT. The field of nuclear cardiology must continue to strive toward more sophisticated but straightforward evaluation of cardiac diseases.