• The Journal of the Korea Contents Association
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• v.3 no.3
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• pp.85-97
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• 2003

Medical tomography images like CT, MRI, PET, SPECT, fMRI, ett have been widely used for diagnosis and treatment of a patient and for clinical study in hospital. In many cases, tomography images are scanned in several different modalities or with time intervals for a single subject for extracting complementary information and comparing one another. 3D image registration is mapping two sets of images for comparison onto common 3D coordinate space, and may be categorized to marker -based matching and feature-based matching. 3D registration of brain images has an important role for visual and quantitative analysis in localization of treatment area of a brain, brain functional research, brain mapping research, and so on. In this article, marker-based and feature-based matching methods which are often used are introduced.

• The KIPS Transactions:PartB
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• v.9B no.5
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• pp.625-634
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• 2002

In this paper, we conducted various experiments with Bayesian networks in order to analyze clinical data of infertility patients. With these experiments, we tried to find out inter-dependencies among important factors playing the key role in clinical pregnancy, and to compare 3 different kinds of Bayesian network classifiers (including NBN, BAN, GBN) in terms of classification performance. As a result of experiments, we found the fact that the most important features playing the key role in clinical pregnancy (Clin) are indication (IND), stimulation, age of female partner (FA), number of ova (ICT), and use of Wallace (ETM), and then discovered inter-dependencies among these features. And we made sure that BAN and GBN, which are more general Bayesian network classifiers permitting inter-dependencies among features, show higher performance than NBN. By comparing Bayesian classifiers based on probabilistic representation and reasoning with other classifiers such as decision trees and k-nearest neighbor methods, we found that the former show higher performance than the latter due to inherent characteristics of clinical domain. finally, we suggested a feature reduction method in which all features except only some ones within Markov blanket of the class node are removed, and investigated by experiments whether such feature reduction can increase the performance of Bayesian classifiers.

• Korean Journal of Radiology
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• v.22 no.3
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• pp.334-343
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• 2021

Objective: We aimed to develop a prediction model for diagnosing severe aortic stenosis (AS) using computed tomography (CT) radiomics features of aortic valve calcium (AVC) and machine learning (ML) algorithms. Materials and Methods: We retrospectively enrolled 408 patients who underwent cardiac CT between March 2010 and August 2017 and had echocardiographic examinations (240 patients with severe AS on echocardiography [the severe AS group] and 168 patients without severe AS [the non-severe AS group]). Data were divided into a training set (312 patients) and a validation set (96 patients). Using non-contrast-enhanced cardiac CT scans, AVC was segmented, and 128 radiomics features for AVC were extracted. After feature selection was performed with three ML algorithms (least absolute shrinkage and selection operator [LASSO], random forests [RFs], and eXtreme Gradient Boosting [XGBoost]), model classifiers for diagnosing severe AS on echocardiography were developed in combination with three different model classifier methods (logistic regression, RF, and XGBoost). The performance (c-index) of each radiomics prediction model was compared with predictions based on AVC volume and score. Results: The radiomics scores derived from LASSO were significantly different between the severe AS and non-severe AS groups in the validation set (median, 1.563 vs. 0.197, respectively, p < 0.001). A radiomics prediction model based on feature selection by LASSO + model classifier by XGBoost showed the highest c-index of 0.921 (95% confidence interval [CI], 0.869-0.973) in the validation set. Compared to prediction models based on AVC volume and score (c-indexes of 0.894 [95% CI, 0.815-0.948] and 0.899 [95% CI, 0.820-0.951], respectively), eight and three of the nine radiomics prediction models showed higher discrimination abilities for severe AS. However, the differences were not statistically significant (p > 0.05 for all). Conclusion: Models based on the radiomics features of AVC and ML algorithms may perform well for diagnosing severe AS, but the added value compared to AVC volume and score should be investigated further.

• The Journal of Korean Medical History
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• v.13 no.1
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• pp.3-19
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• 2000

Seo Dai-chun emphasized the importance of attack on the miasma and created a school to follow classical medical books such as "Nai Kyung"and "Sang Han Ron". Intimate connection between the theory and clinical experience was an unique feature and future generation including Chin Su-won and Wang Tai-lim were deeply influenced. His medical theology and medical case is presented in "Eui Hak Won Ryu Ron"and "Hoi Kye Eui An".

• Advances in pediatric surgery
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• v.10 no.1
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• pp.39-42
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• 2004

Thymolipoma is a rare benign mediastinal tumor, composed of mature fatty and thymic tissues. A 9-year-old boy was referred with a one-month history of neck swelling. Preoperative computed tomography scan and fine needle aspiration biopsy suggested thymolipoma. Despite it being rare, thymolipoma should be considered in the differential diagnosis of mediastinal tumors. Characteristics of its clinical feature and radiological findings that can differentiated it from other mediastinal tumors are discussed with a review of the literatures.

• Journal of Chest Surgery
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• v.21 no.3
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• pp.601-606
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• 1988

Bronchial carcinoid was classified as one of the bronchial adenoma group and it was regarded as benign tumor because of its uniform histologic feature, predictable clinical course and good survivability after surgical resection. But recently, many authors described that bronchial carcinoid has low grade malignancy for its lymphatic spread and distant metastasis, especially atypical carcinoid. We had a case of typical bronchial carcinoid in 20 year old female patient, and successful operation was performed by bilobectomy of middle and lower lob of right lung. Postoperative course was uneventful and discharged without any complication.

• Journal of Korean Neurosurgical Society
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• v.43 no.1
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• pp.45-47
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• 2008

Fungal infections of the spine are relatively uncommon. Moreover, cervical spondylodiscitis due to Candida albicans in non-immunocompromised patient is very rare. We report a case of Candida spondylodiscitis in a 64-year-old woman who complained of neck pain. The clinical feature and treatment option are presented with a review of pertinent literatures.

• The Journal of the Korean dental association
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• v.20 no.11 s.162
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• pp.971-974
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• 1982

The authors observed a case of Cherubism from 8 year-old boy who visited the Dept. of Oral Radiology in S.N.U.H. The patient complained of painless, bilateral swelling on mandibular angle area. Radiologically, sharply defined multiocular radiolucencies are found at both mandibular angle and maxillary posterior area. Another lesion is found at mandibular symphysis area. Interestingly, patient did not show 'look toward heaven' appearance in spite of maxillary involovment. The purpose of this paper if to describe the characteristic clinical, radiological and histopathological feature of the patient without familial involvement.

• Korean Journal of Biological Psychiatry
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• v.4 no.1
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• pp.29-35
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• 1997

Many disorders in neuropsychiatric field demonstrate variable motor disturbances as their clinical feature or in their courses of illness and also due to psychopharmacological treatment. Although association of such motor disturbances with the pathophysiological aspect of various neuropsychiatric illness are still lacking, some form of motor disturbance offer a window through which pathophysiologic mechanism of such illnesses can be viewed. Cognitive control of motor functions are briefly reviewed in this article and the importance and method of motor function assessment in major neuropsychiatric disorders are also discussed. Motor dysfunction of major neuropsychiatric illness such as schizophrenia and mood disorders may offer a chance of a deeper understanding on the pathophysiologic aspect of their clinical presentation.

• Journal of Chest Surgery
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• v.25 no.3
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• pp.330-334
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• 1992

Takayasu`s arteritis is a non-specific arteritis involving the aorta and its major branches. Because of the complexity in the feature of vessel involvement, it represents various clinical presentations according to the sites of involvement. In general, the medical and the surgical treatment of this progressive disease are known to be unsatisfactory but the surgical treatment can provide symptomatic relief and prolong life in selected cases. Recently we experienced one case of Takayasu`s arteritis involving the aortic arch and its major branches. A 45 year-old male patient admitted with the complaints of dizziness, headache, visual disturbance and coldness of upper extremities. Ascending aortogram revealed total occlusion of innominate artery and near total occlusion of left common carotid artery at the site of origin of both vessels. Under the clinical diagnosis of Takayasu`s arteritis, aorto-bicarotid-right subclavian bypass was performed. Postoperative course was uneventful and most of symptoms were relieved except mild residual visual disturbance.