• Journal of Chest Surgery
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• v.13 no.3
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• pp.256-261
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• 1980

Left atrial myxoma constitutes the most significant cardiac tumors, which occupies 30 to 50% of the total in most pathological series with the age range from 3 to 83 years, mostly between the age of 30 to 60 years. Over 90% of myxomas occur in the atria, with 3 to 4 times as many occurring in the left as in the right. They may cause severe and progressive disease mimicking mitral valvular disease with non-specific general symptoms. Recent attentions were focussed in the clinical features along with various diagnostic techniques including angiocardiography, echocardiography and cross-sectional sector scanning echocardiography, and definitive treatment with surgical removal under direct vision using cardiopulmonary bypass. There are several reports on the atrial myxomas removed from various cardiac chambers in Korea, and we report another typical case of left atrial myxoma of 6.8 x 3.8 x 1.7 cm3 attached to the upper margin of fossa ovalis with a short pedicle, also with calcification at it`s distal free end. 29 year old young mother complaining of mild fever, vaginal spotting, numbness of left upper and lower extremities, nocturnal attack of dyspnea and palpitation for 2 months was diagnosed as large left atrial myxoma with the aid of angiocardiography and echocardiography. Trans-right-atrial, transseptal surgical removal of the tumor was successfully performed under the cardiopulmonary bypass for 22 minutes on 24th of July 1980. Postoperative hospital course was uneventful and discharged from hospital on the 12th POD with complete recover from the previous symptoms and signs.

• Imaging Science in Dentistry
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• v.35 no.1
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• pp.47-50
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• 2005

Purpose : To acquire the useful diagnostic information through the analysis of the clinical and radiological characteristics of mandibular unicystic ameloblastoma. Materials and Methods : The researchers compared and analysed the clinical and radiological features of 79 cases of mandibular unicystic ameloblastoma confirmed by histopathlogic examination. Results : The results of our research showed that unicystic ameloblastomas occurred more frequently in males than in females and the incidence is the highest in the 2nd and 3rd decades. These lesions occurred most frequently in angle-ramus area, mandibular molar area, and anterior area in descending order respectively $68.4\%$, $24\%$, and $7.6\%$. These lesions had smooth ($54.4\%$) rather than undulating ($45.6\%$) borders. These lesions showed well- defined borders in $59.5\%$ among all the cases. Root resorption and loss of lamina dura were observed as $55.7\%$ and $58.5\%$ respectively. Displacement of mandibular canal was observed in $55.9\%$ among all the related cases. Internal pattern of lesional radiolucency was observed as even ($49.4\%$) or uneven ($50.6\%$). Conclusion : These results would be helpful in diagnosing of mandibular unicystic ameloblastoma. (Korean J Oral Maxillofac Radiol 2005; 35 : 47-50)

• Journal of Korean Neurosurgical Society
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• v.46 no.1
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• pp.77-80
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• 2009

Orbital solitary fibrous tumor (SFT) is a rare tumor originating from the mesenchyme. We describe the clinical presentations, radiological and operative findings, and pathological features of a patient with orbital SFT. The patient was a 46-year-old female who presented with progressive proptosis advanced for 20 months. On ophthalmological examination, no visual impairment was detected, but left eye was found to be obviously protruded on exophthalmometry. Orbital magnetic resonance imaging showed a 2.5 ${\times}$ 2 ${\times}$ 2 cm, intensely enhanced mass in the left orbit, which compressed the eyeball forward and the optic nerve downward. The patient underwent frontal craniotomy with superior orbitotomy and gross total resection was performed for the tumor. The histopathological diagnosis including immunohistochemistry was a SFT. After the surgery, proptosis was markedly relieved without visual impairment. Although orbital SFT is extremely rare, it should be considered in the differential diagnosis of orbital tumors. Clinical presentations such as painless proptosis and CD34 immunoreactivity play a significant role in differentiating orbital SFT from other spindle-cell neoplasms of the orbit.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.1
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• pp.99-118
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• 2013

Electrocardiograms (ECGs) are widely used by clinicians to identify the functional status of the heart. Thus, there is considerable interest in automated systems for real-time monitoring of arrhythmia. However, intra- and inter-patient variability as well as the computational limits of real-time monitoring poses significant challenges for practical implementations. The former requires that the classification model be adjusted continuously, and the latter requires a reduction in the number and types of ECG features, and thus, the computational burden, necessary to classify different arrhythmias. We propose the use of adaptive learning to automatically train the classifier on up-to-date ECG data, and employ adaptive feature selection to define unique feature subsets pertinent to different types of arrhythmia. Experimental results show that this hybrid technique outperforms conventional approaches and is therefore a promising new intelligent diagnostic tool.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.2
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• pp.183-187
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• 2005

The typical radiologic findings of a small radiolucent nidus with surrounding sclerosis and night pain responding to aspirin make the diagnosis of osteoid osteoma not too difficult. We report a case of multicentric osteoid osteoma with unusual clinical and imaging features which were strongly suggestive of subacute sclerosing osteomyelitis.

• Parasites, Hosts and Diseases
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• v.40 no.3
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• pp.149-151
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• 2002

A 36-year old Korean woman consulted a clinic for a regular gynecological examination, and a mass was noticed in her pelvis. She was referred to the Asan Medical Center, Seoul where transvaginal ultrasonography confirmed a pelvic mass exceeding 10cm in diameter. She received total abdominal hysterectomy and bilateral salpingoophorectomy, and a borderline serous neoplasm with micropapillary features involving the left ovary and right ovarian serosa was histopathologically confirmed. In addition, a section of a nematode with numerous eggs was found in the parenchyma of the left ovary. The worm had degenerated but the eggs were well-preserved and were identified as those of Enterobius vermicularis. She is an incidentally recognized case of ovarian enterobiasis.

• Journal of Chest Surgery
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• v.35 no.8
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• pp.638-641
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• 2002

Low grade fibromyxoid sarcoma is a recently recognized, uncommon soft tissue neoplasm. It has a tendency to develop in deep soft tissue of young adults and a possibility of local recurrence or distant metastasis. Diagnostic criteria have not been well defined and this tumor has not been accepted as a distinct entity. Histologically, it is characterized by the presence of bland spindle cells with mainly whorled pattern of growth, set in alternating areas with a myxoid or fibrous stroma. Careful consideration of the morphological and immunohistochemical features of this tumor permit a positive diagnosis of low grade fibromyxoid sarcoma and allow its distinction from a number of other benign and malignant soft tissue neoplasms. We experienced a low grade fibromyxoid sarcoma in chest wall and report this case with a review of the literature.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.1
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• pp.44-49
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• 2002

In recent years, diagnostic techniques have been investigated to detect a partial discharge(PD) in a high voltage electrical equipment. Because PD signal is very sensitive and difficult to suppress strong noises such as narrow-band radio frequency noise and random noise, the accuracy and credibility of PD measurement might be influenced by surrounding interference. Using the technique of PD detection by electromagnetic wave, we have studied the characteristics of both PD and substation-in interference signal. Also, we propose a wavelet packet transform based technique to perform a feature extraction from the interference and PD signal and a classification of the extracted features. The results show that time-frequency characteristics between PD and interference can be obviously distinguished. It is helpful for the development of the insulation diagnosis technique.

• Tuberculosis and Respiratory Diseases
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• v.47 no.1
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• pp.111-116
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• 1999

Primary hemangiopericytomas of the lung are uncommon sarcomas that arise from pericytes that surround the basement membrane of capillaries and small venules within the lung parenchyma. The presenting symptoms and signs depend on the location of the tumor and radiologic features are not diagnostic. The behavior of pulmonary hemangiopericytomas is difficult to predict and all tumors should be considered potentially malignant. Wide surgical excision remains the mainstay of treatment. We report a case of primary hemangiopericytoma of the lung with a brief review of literature.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.179-184
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• 2010

The digital substation automation system has contributed hugely to increasing the stability of power systems by providing not only protection and control of power systems but diagnostic features alongside them. Digital substation automation systems in the scale of substations consist of integrated operation systems and intelligent electronic devices. The main intelligent electronic devices currently in use are digital protection relays and the bay controllers in Gas insulated switchgears. Proficiently accomplishing the coordination of protection within the power system as a means of ensuring reliability and contriving for the stability of power supply through connection of function, the application of bay controllers is crucial, which collectively manage the protection relay at the bay level in order to achieve both. In this research, the bay controllers to be used in high-voltage Gas insulated switchgear has been localized, and in particular, the logic function and editor required in order to minimize the complicated hardware-like cable connections in the local panel have been developed. In addition, to ensure the strength and reliability of the bay controller hardware developed herein, the type tests from KERI have been successfully completed.