• Journal of Chest Surgery
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• v.26 no.5
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• pp.413-416
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• 1993

Extraskeletal osteogenic sarcoma is a rare malignant tumor of soft tissue, and its predilection sites are the extremity, retroperitoneum, trunk, and the head and neck area. To our knowledge 5 cases of primary involvement of the mediastinum have been reported. Because of its rarity and difficulty in exact diagnosis preoperatively, we report an extraskeletal osteogenic sarcoma in the anterior mediastinum. The patient was a thirty eight old male. He complained of cough and sputum over 2 months. The chest roentgenogram and the chest MRI[magnetic resonance image] were done and showed anterior mediastinal mass with calcification. Excision of the mass was done under the preoperative impression of thymoma, and the pathologic report was extraskeletal osteogenic sarcoma of the mediastinum.

• Journal of Korean Neurosurgical Society
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• v.40 no.2
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• pp.114-116
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• 2006

A Solitary plasmacytoma of bone[SPB] is a rare disease. This paper reports a case of SPB with massive aggregation of histiocytes known as pseudo-Gaucher cells. A 40-year-old male presented with progressive paraparesis and paraesthesia. The Magnetic Resornance Image[MRI] revealed a tumor mass in the thoracic spine that occupied the three colum. The tumor invaded the epidural space of T6 vertebra with compression of the spinal cord. There were no laboratory abnormalities. It was gross totally resected and his neurological symptoms improved. The microscopic examination revealed a plasmacytoma with massive aggregation of histiocytes. Futher neuroradiological studies were carried out and no other lesions were detected.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.92-97
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• 1992

The pulsatile nature of blood flow makes artefacts in 2D Fourier transform image. Spatial presaturation is known to be effective in eliminating flow artefacts when the spin echo acquisition is employed. However. this method requires additional RF pulse and spoiling gradient for presaturation. In this paper a new flow saturation technique which does not require additional saturation-RF and gradient is proposed. The proposed technique is equivalent to the existing saturation technique but the elimination of the flow component is achieved by a pair of tailored $90^{\circ}-180^{\circ}$ RF pulses in tile spin echo sequence. By use of two tailored RF pulses with opposite phase polarity, a linear phase gradient is generated for those moving materials and consequently all the spins of moving materials become dephased thereby no signal is observable. Computer simulations and experimental results obtained using both a phantom and a human volunteer with a 2.0 T whole body system are also presented.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11a
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• pp.511-514
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• 2003

본 연구는 입력된 영상으로부터 특정한 형태를 이루고 있는 대상 물체를 추출함에 있어, 처리에 소요되는 시간 비용(Time cost)을 줄이는 것을 목적으로 하고 있다. 이를 위하여 특정 관심 지역(Region of Interest)이나 대상 물체(Tareet object)의 경계 검출(Boundary detection)을 하는 과정에 통계학적 수치자료(SSM : Statistical Shape Model)를 사용한 접근법을 이용하였다. 또한, 향후 연구 방향인 의료 영상해석(Medical image analysis)으로의 확장성을 고려, 의료 영상 해석에 많이 사용되어지는 MRI, CT, X-Ray 이미지가 Gray level 영상이라는 것을 감안하여 Gray level 영상을 연구 대상으로 삼았다.

• Progress in Superconductivity and Cryogenics
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• v.2 no.1
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• pp.31-34
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• 2000

this paper deals with the initial magnetic field decay for a large scale superconducting magnet e.g. NMR/MRI magnet. The high resolution image can not be obained during the periods of the initial field decay. It is known that all superconducting materials have the property of diamagnetism. This diamagnetism is usually explained with the concept of screening current. We assumed that the existence of the screening currebt. we assumed that the existence of the screening current makes the current distribution in the superconducting wire non-uniform. And the initial magnetic field decay is caused steady current state in the view of its pattern. The initial magnetic field decay is caused by the change of the current distribution between the energizing state and persistent current mode. in this paper the theoretical analysis for the current distributions has been introduced for each state. The experiments have been carried out to verify transport currents in order to veperiments, it small at the higher transport current.

• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.181-185
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• 2008

In this study, we attempted to quantify the relative importance of assumptions regarding blood rheology. Three patient-specific carotid bifurcation geometries and time-varying flow rates were obtained using magnetic resonance imaging. For each subject, CFD simulations were carried out assuming two different non-Newtonian rheology models Carreau and Ballyk models) and rescaled Newtonian viscosities based on characteristic shear rates to account for the shear-thinning property of blood. The sensitivity of WSS and oscillatory shear index (OSI) were contextualized with respect to the reproducibility of the reconstructed geometry and to assumptions regarding the inlet boundary conditions. We conclude that the assumption of Newtonian fluid is reasonable for studies aimed at quantifying the distribution of WSS-based extrema in an image-based CFD model of carotid bifurcation.

• 한국전산유체공학회:학술대회논문집
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• 2008.10a
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• pp.181-185
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• 2008

In this study, we attempted to quantify the relative importance of assumptions regarding blood rheology. Three patient-specific carotid bifurcation geometries and time-varying flow rates were obtained using magnetic resonance imaging. For each subject, CFD simulations were carried out assuming two different non-Newtonian rheology models (Carreau and Ballyk models) and rescaled Newtonian viscosities based on characteristic shear rates to account for the shear-thinning property of blood. The sensitivity of WSS and oscillatory shear index (OSI) were contextualized with respect to the reproducibility of the reconstructed geometry and to assumptions regarding the inlet boundary conditions. We conclude that the assumption of Newtonian fluid is reasonable for studies aimed at quantifying the distribution of WSS-based extrema in an image-based CFD model of carotid bifurcation.

• Journal of the Korea Society of Computer and Information
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• v.22 no.12
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• pp.125-130
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• 2017

Screw insertion surgery is frequently required among surgical procedures. Especially, very careful attention should be paid to the insertion of screw in the operation of the cervical vertebra. Therefore, there is a need for a guide that allows the surgeon to reliably and promptly perform treatment by calculating the desired insertion angle and length for screw insertion. In this study, the center and direction of the pedicle were calculated through 3D modeling and 3D vector numerical analysis using the CT or MRI image of the patient for the safe operation of the guide, and based on this, After that, we will implement surgical guide based on this.

• Clinics in Shoulder and Elbow
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• v.6 no.2
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• pp.173-177
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• 2003

Superficial lipoma was easy to diagnose, but deep lipoma, especially intraosseus lipoma, was difficult to detect pre-operatively. Intraosseous lipoma is very rare and had been difficult to differentiate from other tumors before image diagnosis was developed. Recently, the detecting ratio has increased due to advanced diagnostic tools. Preoperative diagnosis is crucial for the treatment plan and influences the approach method for excision. We experienced one case of misdiagnosis which was diagnosed as intraosseous lipoma according to the preoperative MRI but turned out to be a parosteal lipoma after the surgery.

• Annals of Clinical Neurophysiology
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• v.7 no.1
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• pp.31-33
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• 2005

Segmental zoster paresis (SZP) is a clinically rare complication of herpes zoster. But it has not been reported that acute cerebral motor cortical infarction coincidentally occurred in SZP. A 86-year-old woman was admitted due to pain, tingling sensation, and weakness of left arm. She had an acute onset of pain and tingling sensation in left arm at first day, shoulder weakness at second day, and multifocal vesicles at fourth day. Deep tendon reflexes of left arm were decreased than right. Electromyography showed an axonal polyneuropathy at superior trunk level of left brachial plexus. Median and ulnar sensory evoked potential tests were normal. Brain MRI showed a high signal in right primary motor cortex on diffusion weighted image. We report a case of acute cerebral motor cortical infarction coincidentally occurred in SZP.