• Imaging Science in Dentistry
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• 제35권4호
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• pp.207-213
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• 2005

Purpose: To classify and describe the characteristic features of MRI of some ameloblastoma variants. Materials and Methods: The MR images, CT images, and panoramic radiographs in 5 cases were retrospectively examined as follows. First, the contents of ameloblastomas were devided into two portions of either solid or cystic components on the basis of MR signal intensities. The signal intensity within the solid or cystic portions was classified as homogeneous or heterogeneous. Next, the characteristic internal feature of the lesion on T1W1 or T2WI was described. The signal intensities were classified into low, intermediate, slightly high, high, and strong high signal intensity. Results: Unicystic lesion showed homogeneous high signal intensity (SI) on T2W2 and the rim enhancement of the surrounding area including the mural nodule and the thick wall except the central portion on Gd- T1W1. Solid type revealed heterogeneous and high SI area with strong high SI area on T2W2. On Gd- T1W1, the area corresponding to the low signal spot on T1W1 and the strong high signal spot on T2W1 showed low SI. Hybrid type showed slightly enhanced capsular structures and low SI for the round bony septa and the areas connecting the mixed and cystic lesions on T2Wl and Gd-T1W1. Conclusion: MRI could easily assess the relationship between the mixed and cystic findings in ameloblastoma.

• 대한기계학회논문집A
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• 제27권4호
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• pp.485-490
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• 2003

RP(Rapid Prototyping) has been used in the various industrial applications. This paper presents the optimization techniques fur fabricated 3D model design using RP machine for the medical field. Once the original brain model data are obtained from 2D slices of MRI/CT machine, the data can be modeled as an optimal ellipse. The objective of this study includes optimization of fabrication time and surface roughness using the adaptive slicing method. It can reduce fabrication time without losing surface roughness quality by accumulating the slices with variable thickness. According to the parameter tuning and synthesis of its effect, more suitable parameter values can be obtained by enhanced 3D brain model fabrication. Therefore, accurate 3D brain model fabricated by RP machine can enable a surgeon to perform pre-operation. to make a decision for the operation sequence and to perceive the 3D positions in prototype, before delicate operation of actual surgery.

• Journal of Electrochemical Science and Technology
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• 제7권2호
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• pp.179-184
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• 2016

The interface between the surface of a cathode material and the electrolyte gives rise to surface reactions such as solid electrolyte interface (SEI) and chemical side reactions. These reactions lead to increased surface resistance and charge transfer resistance. It is consequently necessary to improve the electrochemical characteristics by suppressing these reactions. In order to suppress unnecessary surface reactions, we coated cathode material using polypropylene (PP). The PP coating layer effectively reduced the SEI film that is generated after a 4.3 V initial charging process. By mitigating the formation of the SEI film, the PP-coated Li[(Ni_0.6Co_0.1Mn_0.3)_0.36(Ni_0.80Co_0.15Al0.05)_0.64)]O₂(NCS) electrode provided enhanced transport of Li⁺ ions due to reduced SEI resistance (R_SEI) and charge transfer resistance (R_ct). The initial charge and discharge efficiency of the PP-coated NCS electrode was 96.2 % at a current density of 17 mA/g in a voltage range of 3.0 ~ 4.3 V, whereas the efficiency of the NCS electrode was only 94.7 %. The presence of the protective PP layer on the cathode improved the thermal stability by reducing the generated heat, and this was confirmed via DSC analysis by an increased exothermic peak.

• 대한핵의학회지
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• 제35권4호
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• pp.280-285
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• 2001

We present a case of a 31 year-old male patient with tuberculous pericarditis with mediastinal mass that showed increased uptake on Gallium-67 image. Gallium-67 scan was performed to evaluate the activity of the superior mediastinal mass, which was detected on chest CT. A rim of intense activity around the heart was observed, but increased uptake was not seen in the mediastinum. However, on maximal contrast-enhanced SPECT images, a small focus of faint uptake was observed in the superior mediastinum. This finding implied that there was an active tuberculosis in the pericardium and inflammation in the superior mediastinal mass. This case demonstrated that Gallium-67 scinitigraphy was helpful for the diagnosis of tuberculous pericarditis.

• 대한두경부종양학회지
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• 제13권2호
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• pp.269-274
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• 1997

Parotid canalicular adenoma is a benign neoplasm that is predominantly composed of branching and interconnecting cords of single or double rows of columnar epithelium in a very loose stroma. There has been considerable confusion in the literature concerning the terminology of canalicular adenoma. However, thesedays it has been newly-recognized as a discrete entity of the monomorphic adenoma group. Canalicular adenoma has a remarkable predilection for occurrence in the minor salivary glands such as the upper lip, in contrast with basal cell adenoma that occurs predominantly in major salivary glands such as the parotid gland. We have experienced a case of canalicular adenoma of the parotid gland in a 65-year-old woman. The patient had a palpable mass on the preauricular area for the last 15 years and recently noticed a mild pain and discomfort on the mass. Neck ultrasonography showed a low echogenic mass of 1.0cm in diameter in the right parotid gland and a neck CT scan showed a well-enhanced rectangular-shaped mass. A superficial parotidectomy was performed for the lesion and the final pathologic diagnosis turned out to be 'multifocal canalicular adenoma'.

• Imaging Science in Dentistry
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• 제41권4호
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• pp.189-193
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• 2011

The advent and wide use of antibiotics have decreased the incidence of deep neck infection. When a deep neck infection does occur, however, it can be the cause of significant morbidity and death, resulting in airway obstruction, mediastinitis, pericarditis, epidural abscesses, and major vessel erosion. In our clinic, a patient with diffuse chronic osteomyelitis of mandible and fascial space abscess and necrotic fasciitis due to odontogenic infection at the time of first visit came. We successfully treated the patient by early diagnosis using contrast-enhanced CT and follow up dressing through the appropriate use of radiographic images.

• Imaging Science in Dentistry
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• 제39권2호
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• pp.103-107
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• 2009

The present study reports a case of inverted papilloma of the nasal cavity and infiltrating into the maxillary sinus. Inverted papilloma is an uncommon and locally aggressive benign tumor of the sinonasal region. The patient, 51year-old male, presented with unilateral nasal obstruction and periodic swelling on the palate without pain. Enhanced CT scan revealed a heterogeneously enhancing solid mass in the nasal cavity and infiltrating into the right maxillary sinus, as well as an incidental, secondarily infected residual cyst in the periapical area of the right maxillary canine. The sinonasal mass was revealed as an inverted papilloma on histopathologic examination. (Korean J Oral Maxillofac Radiol2009; 39: 103-7)

• Imaging Science in Dentistry
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• 제43권1호
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• pp.55-58
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• 2013

A ranula is a bluish, transparent, and thin-walled swelling in the floor of the mouth. They originate from the extravasation and subsequent accumulation of saliva from the sublingual gland. Ranulas are usually limited to the sublingual space but they sometimes extend to the submandibular space and parapharyngeal space, which is defined as a plunging ranula. A 21-year-old woman presented with a complaint of a large swelling in the left submandibular region. On contrast-enhanced CT images, it dissected across the midline, and extended to the parapharyngeal space posteriorly and to the submandibular space inferiorly. Several septa and a fluid-fluid level within the lesion were also demonstrated. We diagnosed this lesion as a ranula rather than cystic hygroma due to the location of its center and its sublingual tail sign. As plunging ranula and cystic hygroma are managed with different surgical approaches, it is important to differentiate them radiologically.

• Investigative Magnetic Resonance Imaging
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• 제14권2호
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• pp.145-150
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• 2010

소아에서 췌장의 악성 종양은 매우 드물게 발생하고 있으며, 특히 악성 신경내분비 종양은 더더욱 드물다. 저자들은 16세 소아 환자에서 발생한 비기능성 악성 신경내분비 종양의 증례를 경험하여 CT와 MRI 소견을 보고하고자 한다. 췌장 두부에서 발생한 고형 종양으로 조영증강 MRI의 문맥기에서 지연기로 갈수록 조영증강이 잘 되고, 주변의 혈관 침습, 총담관 폐색, 림프절병증 등 악성 소견을 동반할 때 췌장의 비기능성 악성 신경내분비 종양을 감별 진단에 포함하여야 한다.

• Investigative Magnetic Resonance Imaging
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• 제13권1호
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• pp.93-96
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• 2009

요관과 방광에 발생한 일차성 국소 유전분증은 매우 드문 질환이며, 전산화단층촬영과 요도방광경 소견상 악성 종양이나 염증성 병변들과 구분하기 어렵다. 저자들은 일차성 국소 유전분증으로 편측 원위부 요관이 비후된 증례를 보고하고자 하며, T2강조영상에서 저신호강도와 조영증강 T1강조 영상에서 벽의 조영증강형태가 요관 유전분증의 진단에 도움을 줄 수 있는 소견으로 생각된다.