1.Endoscopic Resection of a Giant Duodenal Brunner's Gland Adenoma.
Byung Kook KANG ; Nam Seon PARK ; Dae Ho JIN ; Tae Hong AHN ; Min Bom PARK ; Key Jo LEE ; Yoon Ju HAN ; Hyo Jin PARK
The Korean Journal of Gastroenterology 2008;52(2):106-109
Brunner's gland adenoma is a rare tumor of duodenum. Patients are usually aymptomatic and most are discovered incidentally during the upper gastrointestinal (GI) series or esophagogastroduodenoscopy. These lesions are most commonly located in the duodenal bulb and clinical manifestations are variable. In symptomatic patients, the most common manifestations are GI hemorrhage and duodenal obstruction. On histologic examination, Brunner's gland adenoma that causes clinical symptoms is composed of hyperplastic Brunner's glands and contains mostly an admixture of glandular, adipose, and muscular tissues. We report a case of large Brunner's gland adenoma causing upper gastrointestinal hemorrhage in a 47-year-old woman which was successfully removed by endoscopic resection without complications such as bleeding or perforation. Microscopically, it was entirely composed of variable Brunner's glands.
Adenoma/complications/*pathology/surgery
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Brunner Glands/*pathology/surgery
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Duodenal Neoplasms/complications/*pathology/surgery
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Duodenoscopy
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Female
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Gastrointestinal Hemorrhage/etiology
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Humans
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Middle Aged
2.Recent Advances in Nuclear Medicine Imaging Instrumentation.
Jin Ho JUNG ; Yong CHOI ; Key Jo HONG ; Byung Jun MIN ; Wei HU ; Ji Hoon KANG
Nuclear Medicine and Molecular Imaging 2008;42(2):98-111
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.
Biological Processes
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Chimera
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Electronics
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Electrons
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Models, Animal
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Molecular Imaging
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Myocardial Perfusion Imaging
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Nuclear Medicine
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Positron-Emission Tomography
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Positron-Emission Tomography and Computed Tomography
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Signal-To-Noise Ratio
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Tomography, Emission-Computed, Single-Photon
3.Development of a Small Animal Positron Emission Tomography Using Dual-Layer Phoswich Detector and Position Sensitive Photomultiplier Tube: Preliminary Results.
Myung Hwan JEONG ; Yong CHOI ; Yong Hyun CHUNG ; Tae Yong SONG ; Jin Ho JUNG ; Key Jo HONG ; Byung Jun MIN ; Yearn Seong CHOE ; Kyung Han LEE ; Byung Tae KIM
Korean Journal of Nuclear Medicine 2004;38(5):338-343
PURPOSE: The purpose of this study was to develop a small animal PET using dual layer phoswich detector to minimize parallax error that degrades spatial resolution at the outer part of field-of-view (FOV). MATERIALS AND METHODS: A simulation tool GATE (Geant4 Application for Tomographic Emission) was used to derive optimal parameters of small PET, and PET was developed employing the parameters. Lutetium Oxyorthosilicate (LSO) and Lutetium-Yttrium Aluminate-Perovskite (LuYAP) was used to construct dual layer phoswitch crystal. 8 X 8 arrays of LSO and LuYAP pixels, 2 mm X 2 mm X 8 mm in size, were coupled to a 64-channel position sensitive photomultiplier tube. The system consisted of 16 detector modules arranged to one ring configuration (ring inner diameter 10 cm, FOV of 8 cm). The data from phoswich detector modules were fed into an ADC board in the data acquisition and preprocessing PC via sockets, decoder block, FPGA board, and bus board. These were linked to the master PC that stored the events data on hard disk. RESULTS: In a preliminary test of the system, reconstructed images were obtained by using a pair of detectors and sensitivity and spatial resolution were measured. Spatial resolution was 2.3 mm FWHM and sensitivity was 10.9 cps/micro Ci at the center of FOV. CONCLUSION: The radioactivity distribution patterns were accurately represented in sinograms and images obtained by PET with a pair of detectors. These preliminary results indicate that it is promising to develop a high performance small animal PET.
Animals*
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Electrons*
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Lutetium
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Positron-Emission Tomography*
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Radioactivity
4.A Case Report of Tuberculous Brain Abscess and Tuberculous Peritonitis Developing Due to Paradoxical Reactions.
Tae Hong AHN ; Min Bum PARK ; Key Jo LEE ; Eun Ho JUNG ; Jin Woo KIM ; Sang Yeol SUH ; Seok Woo KANG ; Eun Na KIM ; Yoon Ju HAN ; Sam Kwon CHO
Tuberculosis and Respiratory Diseases 2009;66(6):457-462
While receiving appropriate treatment, patients with tuberculosis occasionally have unusual, paradoxical reactions, with transient worsening of lesions or the development of new lesions. This report is a case of tuberculosis brain abscess and tuberculosis peritonitis with intra-abdominal abscess that developed during appropriate anti-tuberculosis chemotherapy. A 45-year-old male patient had been diagnosed as with all-drug susceptible pulmonary tuberculosis with pleurisy. Subsequently, the patient underwent standard treatment with anti-tuberculosis therapy; the pulmonary lesions improved. Three months after initial treatment, the patient developed brain abscesses and peritonitis. With the addition of corticosteroid treatment, the patient's neurologic symptoms were relieved. Exploratory laparotomy with surgical drainage was performed and a diagnosis of tuberculosis peritonitis was confirmed on biopsy. Anti-tuberculosis therapy was continued for 19 months, the patient improved eventually without further complications, although the therapeutic regimen had not been altered. In this case, the paradoxical response to treatment may have been involved in the pathogenesis of disease.
Abdominal Abscess
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Biopsy
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Brain
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Brain Abscess
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Drainage
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Humans
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Laparotomy
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Male
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Middle Aged
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Neurologic Manifestations
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Peritonitis
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Peritonitis, Tuberculous
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Pleurisy
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Tuberculosis
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Tuberculosis, Pulmonary
5.Endosonographic Features of Gastric Schwannoma: A Single Center Experience.
Jong Min YOON ; Gwang Ha KIM ; Do Youn PARK ; Na Ri SHIN ; Sangjeong AHN ; Chul Hong PARK ; Jin Sung LEE ; Key Jo LEE ; Bong Eun LEE ; Geun Am SONG
Clinical Endoscopy 2016;49(6):548-554
BACKGROUND/AIMS: Gastric schwannomas are rare benign mesenchymal tumors that are difficult to differentiate from other mesenchymal tumors with malignant potential, such as gastrointestinal stromal tumors. This study aimed to evaluate the characteristic findings of gastric schwannomas via endoscopic ultrasonography (EUS). METHODS: We retrospectively reviewed the EUS findings of 27 gastric schwannoma cases that underwent surgical excision at Pusan National University Hospital during 2007 to 2014. RESULTS: Gastric schwannomas were mainly located in the middle third of the stomach with a mean tumor size of 32 mm. All lesions exhibited hypoechoic echogenicity, and 24 lesions (88.9%) exhibited heterogeneous echogenicity. Seventeen lesions (63.0%) exhibited decreased echogenicity compared to the normal proper muscle layer. Distinct borders were observed in 24 lesions (88.9%), lobulated margins were observed in six lesions (22.2%), and marginal haloes were observed in 24 lesions (88.9%). Hyperechogenic spots were observed in 21 lesions (77.8%), calcifications were observed in one lesion (3.7%), and cystic changes were observed in two lesions (7.4%). CONCLUSIONS: During EUS, gastric schwannomas appear as heterogeneously hypoechoic lesions with decreased echogenicity compared to the normal proper muscle layer. These features may be helpful for differentiating gastric schwannomas from other mesenchymal tumors.
Busan
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Endosonography
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Gastrointestinal Stromal Tumors
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Neurilemmoma*
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Retrospective Studies
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Stomach
6.A Computer Simulation for Small Animal Iodine-125 SPECT Development.
Jin Ho JUNG ; Yong CHOI ; Yong Hyun CHUNG ; Tae Yong SONG ; Myung Hwan JEONG ; Key Jo HONG ; Byung Jun MIN ; Yearn Seong CHOE ; Kyung Han LEE ; Byung Tae KIM
Korean Journal of Nuclear Medicine 2004;38(1):74-84
PURPOSE: Since I-125 emits low energy (27-35 keV) radiation, thinner crystal and collimator could be employed and, hence, it is favorable to obtain high quality images. The purpose of this study was to derive the optimized parameters of I-125 SPECT using a new simulation tool, GATE (Geant4 Application for Tomographic Emission). MATERIALS AND METHODS: To validate the simulation method, gamma camera developed by Weisenberger et al. was modeled. NaI (Tl) plate crystal was used and its thickness was determined by calculating detection efficiency. Spatial resolution and sensitivity curves were estimated by changing variable parameters for parallel-hole and pinhole collimator. Performances of I-125 SPECT equipped with the optimal collimator were also estimated. RESULTS: In the validation study, simulations were found to agree well with experimental measurements in spatial resolution (4%) and sensitivity (3%). In order to acquire 98% gamma ray detection efficiency, NaI (Tl) thickness was determined to be 1 mm. Hole diameter (mm), length (mm) and shape were chosen to be 0.2: 5: square and 0.5: 10: hexagonal for high resolution (HR) and general purpose (GP) parallel-hole collimator, respectively. Hole diameter, channel height and acceptance angle of pinhole (PH) collimator were determined to be 0.25 mm, 0.1 mm and 90 degree. The spatial resolutions of reconstructed image of the I-125 SPECT employing HR: GP: PH were 1.2: 1.7: 0.8 mm. The sensitivities of HR: GP: PH were 39.7: 71.9: 5.5 cps/MBq. CONCLUSION: The optimal crystal and collimator parameters for I-125 imaging were derived by simulation using GATE. The results indicate that excellent resolution and sensitivity imaging is feasible using I-125 SPECT.
Animals*
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Computer Simulation*
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Gamma Cameras
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Gamma Rays
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Hydrogen-Ion Concentration
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Tomography, Emission-Computed, Single-Photon*