• Journal of Chest Surgery
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• v.47 no.5
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• pp.465-467
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• 2014

We present a patient who developed recurrent angina after coronary artery bypass grafting (CABG). Myocardial single-photon emission computed tomography (SPECT) demonstrated deterioration in the myocardial perfusion, and coronary angiography revealed an overgrown side branch of the grafted left internal thoracic artery (ITA); otherwise, there were no significant changes compared with previous imaging studies obtained after the CABG. After percutaneous embolization of the grafted left ITA side branch, the angina was resolved and myocardial SPECT showed improved perfusion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.131-134
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• 2000

Electroluminescent[EL] from conjugated polymers has recently received great attention because polymer light-emitting diodes[LEDs] clearly have potential for applications such as large-area displays. The operation of polymer LEDs is based on double injection of electrons and holes from the electrodes, followed by formation of excitons whose radiative decay results in light emission at wavelength characteristic to the material In this paper, we fabricated the single layer EL device using poly(3-octylthiophene)[P3OT] as emitting material. The orange-red light was clearly visible in a dark room Maximum peak wavelength of EL spectrum saw at 640nm in accordance with photon energy 1.9eV. And we know that ionization energy of P3OT is 4.7eV from the cyclic voltammetry.

• Journal of radiological science and technology
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• v.19 no.1
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• pp.89-94
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• 1996

Misalignment between the electronic and mechanical axes of rotation will result in artifact generation and image degradation during single photon emission computed tomography(SPECT) reconstruction. Acceptance and quality control testing procedures have not emphasized the variability in center of rotation(COR) measurements caused by collimators and the need to verify uniformity across the full collimator field of view (FOV). Variation from the mean COR across the FOV was tested in four different collimators using multiple point source acquisitions. The mean COR was different for each collimator and one of the four had a > 0.5 pixel difference from the mean COR on some area of the FOV, This variation makes this collimator unacceptable for SPECT acquisition. Thus, initial acceptance testing of SPECT collimators should verify a uniform COR across the full FOV and collimators with a variability from the mean COR > 0.5 pixels should be rejected.

• Journal of Chest Surgery
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• v.45 no.4
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• pp.251-253
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• 2012

We report a redo coronary artery bypass grafting (CABG) in a 55-year-old man. Angina recurred 7 years after the initial surgery. Coronary angiography showed all patent grafts except a faint visualization of the in situ right gastroepiploic artery (RGEA) graft, which was anastomosed to the posterior descending coronary artery, associated with celiac axis stenosis. Redo-CABG was performed at postoperative 10 years because of aggravated angina and decreased perfusion of the inferior wall in the myocardial single photon emission computed tomography. The saphenous vein graft was interposed between the 2 in situ grafts used previously; the right internal thoracic artery and RGEA grafts. Angina was relieved and myocardial perfusion was improved.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.437-442
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• 2001

For ischemic cerebrovascular disease, it is well known that early luxury perfusion is related to a good clinical outcome and single photon emission computed tomography(SPECT) has the potential for providing useful information about regional cerebral blood flow. We report one case of Rt. MCA infarction mainly treated by oriental medicine and revealed luxury perfusion without thrombolysis. In acute stage, neurological deficits of the patient were very severe. 99mTc-HMPAO SPECT images obtained 10days after the attack showed large perfusion defect in the Rt. MCA territory. We followed up 99mTc-HMPAO SPECT 40days after the ictus. Despite of the poor early perfusion, we found considerably improved perfusion and neurological improvement.

• The Korean Journal of Nuclear Medicine
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• v.37 no.1
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• pp.34-42
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• 2003

The dopamine transporter (DAT) is responsible for the re-uptake of dopamine from the synaptic cleft and is located on dopaminergic nerve terminals only. DAT single photon emission computed tomography (SPECT) and positron omission tomography (PET) imaging, therefore, offer the unique opportunity to study via striatal uptake the integrity of presynaptic dopaminergic nerve terminals in vivo. In recent years SPECT and PET using specific ligands binding to DAT have evolved as an useful tool for diagnosing and monitoring progression of neurodegenerative disorders affecting dopaminergic systems. This article briefly reviews the literature dealing with DAT SPECT and PET imaging in parkinsonism and other neurodegenerative disorders.

• Journal of Radiation Industry
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• v.6 no.3
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• pp.245-249
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• 2012

Demand of fluid flow visualization has increased in industrial processes, because medical imaging technology is highly developed. As a part of the industrial process imaging technology, industrial single photon emission computed tomography (SPECT) system was developed to measure the cross-sectional distribution of the process fluid. The SPECT consists of 36 NaI (Tl) detectors with the hexagonal configuration. Reconstructed images were acquired for various positions of radioactive source to estimate SPECT device performance. To evaluate the reliability of the experimental results, the Monte Carlo simulation results are compared with experimental results. In general, the experimental and simulation results were consistent. However, as the source position was getting far from the center of the reactor, the accuracy of reconstructed images was compromised. It seems to be due to the inconsistent spatial resolution of the collimators according to the source position.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.23-27
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• 2014

Industrial single photon emission computed tomography (SPECT) is an useful technique to investigate the dynamic behavior of process flow. In the present study, to evaluate the influence of a void on the performance of industrial SPECT, industrial SPECT with various radioisotope sources and gas holdups was modeled by the Monte Carlo simulation. The results are very encouraging; that is, the void little influences the performance of industrial SPECT, which means that industrial SPECT could be a suitable tool to investigate the dynamic characteristics of the flow in a water-air phase process.

• The Korean Journal of Nuclear Medicine Technology
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• v.28 no.1
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• pp.1-11
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• 2024

Hypoxia, defined as the deficiency of oxygen, is a significant hallmark of cancers presenting in the majority of solid tumors. Detection of tumor hypoxia is essential in cancer diagnosis to prevent cancer progression, metastasis, and resistance to cancer therapies in clinical practices. Single-photon emission computed tomography (SPECT) is one of the methods studied and applied for hypoxia detection with the use of radiolabeled imaging agents in which ^99mTc is the common radioisotope used for radiolabeling. Nitroimidazoles are the hypoxia-targeting moieties presenting in numerous ^99mTc-radiolabeled imaging agents due to their bio-reducible ability in hypoxic environments. Recently, in addition to ^99mTc-labeled radiopharmaceuticals containing one nitroimidazole unit, there has been considerable attention given to ^99mTc-radiopharmaceuticals bearing two or more nitroimidazole units. This review summarizes the synthesis of hypoxia-targeting chelators and radiolabeling processes to produce these ^99mTc-radiopharmaceuticals for SPECT imaging.

• Journal of the Korean Orthopaedic Association
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• v.54 no.6
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• pp.509-518
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• 2019

Purpose: Lymph node metastasis is a very important prognostic factor for all skin cancers and some sarcomas. A sentinel lymph node (SLN) biopsy is the most useful technique for identifying SLNs. Recently, a new generation of diagnostic tools, such as single photon emission computed tomography/computed tomography (SPECT/CT) and positron emission tomography/CT (PET/CT) enabled the detection of SLNs. This study compared the efficacy of PET/CT for detecting lymph node metastases with a SLN biopsy in a single medical center. Materials and Methods: From 2008 to 2018, 72 skin cancers of sarcoma patients diagnosed with some lymph node involvement in a whole body PET/CT reading were assessed. Patients suspected of lymph node metastasis were sent to biopsy and those suspected to be reactive lesions were observed. The analysis was performed retrospectively using the medical records, clinical information, PET/CT readings, and pathology results. Results: The age of patients ranged from 14 to 88 years and the mean follow-up period was 2.4 years. Twenty-two patients were suspected of a lymph node metastasis and confirmed. The sensitivity, specificity, positive predictive value and negative predictive value of PET/CT images in sarcoma and non-sarcoma tumors were increased significantly when the expert's findings were considered together. Conclusion: PET/CT is effective in detecting lymph node metastases.