• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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• pp.51-62
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• 2008

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.5
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• pp.305-310
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• 2015

We propose a new concept for a depth of interaction (DOI) positron emission tomography (PET) detector based on dual-ended-scintillator (DES) readout for small animal imaging. The detector consists of lutetium yttrium orthosilicate (LYSO) arrays coupled with orthogonal wavelength-shifting (WLS) fibre placed on the top and bottom of the arrays. On every other line, crystals that are 2 mm shorter are arranged to create grooves. WLS fibre is inserted into these grooves. This paper describes the design and performance evaluation of this PET detector using Monte Carlo simulations. To investigate sensitivity by crystal size, five types of PET detectors were simulated. Because the proposed detector is composed of crystals with three different lengths, degradation in sensitivity across the field of view was also explored by simulation. In addition, the effect of DOI resolution on image quality was demonstrated. The simulation results proved that the devised PET detector with excellent DOI resolution is helpful for reducing the channels of sensors/electronics and minimizing gamma ray attenuation and scattering while maintaining good detector performance.

• The Korean Journal of Nuclear Medicine
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• v.32 no.6
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• pp.534-541
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• 1998

We describe a 27-year-old man who developed gait disturbance and dysarthria 2 years after the onset of cardinal symptoms of Behcet's disease. Positron emission tomography with $^{18}F$-fluorodeoxyglucose revealed severe hypometabolisrn in the cerebellum, in accordance with cerebellar symptoms and signs of the patient. However, single-photon emission tomography with $^{99m}Tc$-HMPAO and $^{99m}Tc$-ECD did not disclose significant perfusion abnormalities in the brain. Routine brain magnetic resonance imaging did not show signal abnormalities. The findings of imaging studies compared with neurological manifestations of the patient are discussed.

• Journal of the Korean Vacuum Society
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• v.13 no.2
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• pp.92-98
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• 2004

DBPAS has been used to characterize atomic size defect structures in materials. In this investigation the numerical analysis of the Doppler spectra was employed to the determination of the shape parameter, S, defined as the ratio between the amount of counts in a central portion of the spectrum and the total counts of whole spectrum. As the samples were exposed by X-ray increasing the exposed doses from 3, 6, and 9 Gy with 6 MV and 15 MV, respectively and also irradiated by X-ray as the medical applications used for in 0, 2, 4 and 6 years. The S-parameter values were increased as increasing the exposed time and the energies, that indicated the defects generate more. The S-parameters of the samples with medical treatment is varied from 0.4932 to 0.4956.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.46-51
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• 2008

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasm of the gastrointestinal tract, and can be distinguished from the smooth muscle or neural tumors in approximately 95% of patients by expression of the KIT receptor tyrosine kinase (CD117). GISTs are known to have high malignant potential and none can be labeled definitely as benign. However, GISTs are unresponsive to standard sarcoma chemotherapy, and only complete surgical resection provides chance for cure. Although the imaging modality of choice is enhanced CT scan in patients with GIST, FDG PET can reflect the malignant potential of GIST. Clinical management of patients with GISTs has dramatically changed with the introduction of novel therapeutics, such as imatinib mesylate (Glivec). This has created a need to re-evaluate the existing criteria used to assess treatment response. FDG PET as functional imaging modality proved to be significantly more accurate than CT alone when assessing GIST response to imatinib. And, FDG PET and PET ICT have been found to be highly sensitive in detecting early response, and to be useful in predicting long-term response to imatinib in patients with recurrent or metastatic GISTs.

• 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.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.1
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• pp.1-8
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• 2015

It is essential use of long term half life radioisotopes for positron emission tomography (PET) imaging study of biopharmaceuticals because most of biopharmaceuticals have long biological half-life. Some representative isotopes are $^{124}I$, $^{64}Cu$, $^{89}Zr$ and so on. These PET radioisotopes and their radiopharmaceuticals have recently received growing interest because of long half life and good imaging properties. Furthermore, $^{64}Cu$ and $^{89}Zr$ can be used in a number of radiopharmaceuticals due to its ease of conjugation to peptides and antibodies using the proper chelator. In recent years, since $^{124}I$ was first developed in 2005, we have been studied to develop an efficient method and procedure for producing these radioisotopes, and we have made considerable progress in production of long term half life radioisotopes. This review introduces the general production system, purification procedure, and several advances on targeting method for $^{124}I$ and $^{64}Cu$ in KIRAMS.

• Parasites, Hosts and Diseases
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• v.49 no.1
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• pp.69-72
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• 2011

Pulmonary paragonimiasis is a relatively rare cause of lung disease revealing a wide variety of radiologic findings, such as air-space consolidation, nodules, and cysts. We describe here a case of pulmonary paragonimiasis in a 27-year-old woman who presented with a 2-month history of cough and sputum. Based on chest computed tomography (CT) scans and fluorodeoxyglucose positron emission tomography (FDG-PET) findings, the patient was suspected to have a metastatic lung tumor. However, she was diagnosed as having Paragonimus westermani infection by an immunoserological examination using ELISA. Follow-up chest X-ray and CT scans after chemotherapy with praziquantel showed an obvious improvement. There have been several reported cases of pulmonary paragonimiasis mimicking lung tumors on FDG-PET. However, all of them were suspected as primary lung tumors. To our knowledge, this patient represents the first case of paragonimiasis mimicking metastatic lung disease on FDG-PET CT imaging.

• Korean Journal of Veterinary Research
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• v.52 no.3
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• pp.205-208
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• 2012

Endocrine test data from a 13-year old intact female Maltese was indicative of the presence of an insulinoma, however ultrasonography identified a pancreatic mass only after 10 months after the first admission. Following identification of both pancreatic tumor and hepatic metastasis on computed tomography (CT), surgical excision of the mass was attempted. However, total excision failed because of tumor adhesion to adjacent large vessels. The pancreatic mass was monitored over the next 25 months via ultrasonography, CT, and positron emission tomography-computed tomography (PET-CT). Histopathological and immunohistochemical data confirmed the diagnosis of insulinoma with hepatic metastasis.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.326-330
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• 1994

A $^{82}Sr/^{82}Rb$ generator was prepared by loading $^{82}Sr$ to preconditioned tin dioxide column. The generator was eluted by normal saline with flow rate up to 8m1/min, and the eluted radioactivity was monitored by dose calibrator. Radioactivity began to come out at 5ml and reached to peak around 9ml. The total eluted radioactivity increased linearly with flow rate, and the maximum obtained radioactivity was 35mCi at 8m1/min. The $^{82}Rb$ preparation was proven to be free from both strontium radioactivity and pyrogen. The $^{82}Rb$ was injected to normal female volunteer and positron emission tomographic Image of heart was obtained successfully.