• 대한의용생체공학회:의공학회지
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• 제22권3호
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• pp.223-229
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• 2001

In this paper, we have compared the direct fan-beam reconstruction method with the rebinning method in terms of computation time and spatial resolution using computer simulation. As a result, the direct fan-beam method is superior to the rebinning method in the spatial resolution though the former needs longer computation time. However, if we adopt the quarter-detector-offset technique to improve the spatial resolution, the rebinning method outperforms the direct fan-beam method. The computation times have been evaluated using the fast algorithms optimized to reduce the number of interpolation calculations at the back-projection, and the spatial resolutions have been compared using the computer generated phantoms.

• 대한세포병리학회지
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• 제3권2호
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• pp.100-103
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• 1992

We experienced a case of primary hepatic actinomycosis which was initially diagnosed by means of fine needle aspiration. The patient was a 31-year-old emaciated man with a 2-month history of 10 kg weight loss, right upper quadrant pain and flank pain. The liver was palpable and tender on physical examination. Computerized tomography scan of the liver showed two ill-defined hypodense masses in gallbladder fossa and inferior pole of right lobe. Hepatocellular carcinoma was clinically suspected. A CT-guided fine needle aspiration was peformed. Microscopically, smears showed numerous radiating clusters of filamentous bacteria with many neutrophils and monocytes in necrotic background. The symptoms were improved by incision and drainage and massive administration of penicillin.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.714-719
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• 2004

This paper presents two numerical algorithms for registration of cross-sectional medical images such as CT (Computerized Tomography) or MRI (Magnetic Resonance Imaging) by using geometrical information from helix or line fiducials. The registration algorithms are designed to be used for a surgical robot working inside cavities of human body. A cylindrical device with a combination of line and helix fiducials were also devised and is supposed to be attached to the end-effector of surgical robot. The algorithms and the fiducial pattern were tested in various computer-simulated situations, and the results indicate excellent overall registration accuracy.

• Journal of Mechanical Science and Technology
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• 제16권12호
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• pp.1627-1632
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• 2002

In this paper, a simplified ultrasonic CT system, which uses the information in three directions, that is, 90°, ＋45° and －45°about the inspection plane, is applied to the high strength steel, and the frequency analysis method for enhancing the C scan or CT image is developed. This frequency analysis method is based on the frequency response property of the material. By comparing the magnitudes in the frequency domain, the special frequency which shows a significant difference between the welded joint and base material was found and used to obtain a C scan or CT image. Experimental results for several kinds of specimens, having a welded joint by electron beam welding, a weld joint by arc welding, on a fatigue crack, showed that the obtained C scan or CT image has better resolution than the results of previous experiments using the maximum value of the received waveform.

• Clinical and Experimental Pediatrics
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• 제56권10호
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• pp.451-455
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• 2013

Sialolithiasis is caused by the obstruction of a salivary gland or its excretory duct by the formation of calcareous concretions or sialoliths; this results in salivary ectasia and provokes subsequent dilation of the salivary gland. Sialolithiasis is relatively common, accounting for 30% of salivary diseases; however, it is rarely observed in childhood. This case report describes a 2-year-old male patient who complained of a painful swelling over the right cheek, and presented with palpable stones and pus discharge from the orifice of the right Stensen's duct. Computerized tomography of the neck confirmed the diagnosis, and the patient received intravenous empiric antibiotics combined with intraoral sialolithotomy. We also provide a review of the spectrum of concepts regarding the pathogenesis, diagnosis, and treatment of sialolithiasis.

• Journal of Chest Surgery
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• 제25권3호
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• pp.335-340
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• 1992

Truamatic aortic rupture is usually fatal if left untreated. Prompt diagnosis is the cornerstone of suscessful management. But the usual screening tests are non specific and the accuracy of computerized tomography is low, Aortography which is a time consuming procedure may result in false-positive interpretations and significant morbidity. Recently transesophageal echocardiography provides a rapid, effective and relatively safe means of evaluating the distal aortic arch and also affords the opportunity to evaluate the heart during the same study, which may be of benefit in cases of suspected cardiac injury. The experience with the traumatic aortic ruptured patient and a critical review of the literature suggests that transesophageal echocardiography is a useful technique for the diagnosis of ruptured aorta following blunt chest trauma.

• Journal of Korean Neurosurgical Society
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• 제42권5호
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• pp.403-405
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• 2007

Most posttraumatic cerebrospinal fluid (CSF) leakage is noticed by the patients with the first symptom, rhinorrhea. A 38-year-old woman presented with frequent clear continuous rhinorrhea and otorrhea for 5 years after basilar skull fracture. After this, meningitis was developed with subsequent CSF fistula. Her clinical symptom was improved by medical treatment. The dural defect and CSF leakage were not detected by computerized tomography (CT) cistemography. We report a rare case of persistent posttraumatic CSF fistula that continued for five years.

• Journal of Yeungnam Medical Science
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• 제3권1호
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• pp.339-342
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• 1986

저자들은 57세의 남자에서 췌장염에서 기인하였다고 사료되는 다발성 비장농양을 치험하였으며 복부 패혈증 시 전산화 단층촬영을 조기에 실시함으로서 진단과 치료에 좋은 결과를 얻었기에 문헌고찰과 함께 보고하는 바이다.

• Journal of Korean Neurosurgical Society
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• 제40권5호
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• pp.377-380
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• 2006

Intradiploic epidermoid cysts of the cranium are rare, benign and slow growing lesion. However, these cysts may cause neurologic deficits due to mass effect. Intradiploic epidermoid cysts are thought to be derived from persistent ectodermal remnants present in the cranial bones during embryogenic development. Here, we report a case of an occipital intradiploic epidermoid cyst with posterior fossa extension. The patient developed intracranial hypertension associated with hydrocephalus due to aqueductal stenosis, and venous congestion secondary to compression of the torcular and the transverse sinus. The imaging studies included a computerized tomography[CT] venogram, which is essential for determining the pathophysiological mechanism of the clinical spectrum and for surgical planning. Near total removal was accomplished and the postoperative course was uneventful. Postoperative imaging studies demonstrated a reversal of the neural structures, but no patency of the sinus, which was presumably indicative of prolonged sinus stenosis. The patient gradually improved and was discharged free of symptoms.

• Journal of Korean Neurosurgical Society
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• 제29권9호
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• pp.1258-1261
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• 2000

Intraspinal neurenteric cyst is rare congenital lesion derived from disorder of notochord formation. Most of these are located ventral to the spinal cord and conventional posterior approach is considered to be effective method as initial treatment modality. This cyst can recur, but the risk of reccurence after partial removal through long term follow-up has not been determined. We experienced one case of cervical neurenteric cyst which recurred after partial removal through laminectomy. The magnetic resonance imaging and postmyelography computerized tomography revealed an intradural extramedullary cystic lesion anterior to the cervical cord at the fifth cervical vertebra level. We performed anterior cervical corpectomy and cyst was totally removed. The patient's neurological symptom was improved postoperatively. Neurenteric cyst located ventrally to the cervical spinal cord should be removed through anterior route for direct visualization of the relationship between the cyst wall and the spinal cord.