• Journal of radiological science and technology
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• v.28 no.4
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• pp.287-291
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• 2005

To determine the appropriate session for changing treatment modality according to the size of proximal ureter stone with complete obstruction, We analyzed 201 patients with proximal ureter stone primarily treated by Dornier MPL 9000 lithotripter from January, 2002 to August, 2004. Of total 201 patients, the patients without complete obstruction were 142, and with complete obstruction were 59. In the patients without complete obstruction, the accumulative stone free rate of the first, second, and third session were 68.3%, 86.6%, and 94.4%, respectively. The accumulative stone free rate according to the stone size at third session were 100%, 90.5%, 00.0% in stones less than 10 mm, 10 to less than 20 mm, and larger than or 20 mm, respectively. In the patients with complete obstruction, the accumulative stone free rate of the first, second, and third session were 44.1%, 66.1%, and 76.3%, respectively. The accumulative stone free rate according to the stone size at third session were 100%, 65.5%, 33.3% in stones less than 10 mm, 10 to less than 20 mm, and larger than or 20 mm, respectively. In our study, the size of proximal ureter stone with complete obstruction influenced noticeably on the success rate of extracorporeal shock wave lithotripsy (ESWL). We propose that the proximal ureter stones larger than or 10 mm with complete obstruction are treated by ureteroscopic manipulation than ESWL as the first line treatment modality.

• Proceedings of the KSRS Conference
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• 2000.04a
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• pp.143-148
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• 2000

레이저 프로파일링 시스템의 등장으로, 기존에는 얻을 수 없었던 도시 지역에 대한 DTM 취득이 가능해졌고, 더욱 정확한 정사투영영상 또한 제작할 수 있게 되었다. 하지만, 높이 변화를 보이는 자연지물과 인공구조물이 있는 지역에 대해 기존의 정사투영사진 제작기법이 적용될 때, 폐색이나 이중매핑과 같은 문제가 발생하게 된다. 특히 고층건물이 밀집되어 있는 도심지에서 이러한 현상은 두드러져 정사투영영상의 품질을 저해하는 주요한 원인이 된다. 따라서, 본 연구에서는 카메라의 외부표정요소와 DTM을 이용하여 폐색영역을 탐지하고, 폐색이 안된 다른 영상의 정보를 통해 폐색영역을 복원하여 더욱 완전한 정사투영을 제작할 수 있는 알고리즘을 제안하였다. 제안된 알고리즘에 의해 자연지물이나 인공고조물에 의한 폐색영역을 탐지할 수 있었고 폐색영역의 많은 부분을 부가영상을 이용하여 복원하였다. 건물에 대한 사전지식을 이용하여 폐색영역을 탐지하는 국내 연구가 있지만, 본 연구는 건물에 대한 부가정보나 모델링을 사용하지 않고 DTM과 카메라 외부표정요소만을 이용하여 폐색영역을 탐지한다는 점에서 이러한 연구들과 차별성을 가진다.

• Journal of Chest Surgery
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• v.36 no.7
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• pp.531-534
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• 2003

A 43-year-old woman who had had an invasive mole 5 years previously required emergent pulmonary embolectomy under cardiopulmonary bypass. Curative resection was impossible because the tumor invaded the right main pulmonary artery and left lower pulmonary artery. The pathologic diagnosis made by the tumor emboli specimens was choriocarcinoma. The patient received post-operative chemotherapy over a 6-month period and had complete remission. Although rare, choriocarcinoma should be considered in the differential diagnosis of fertile women presented with pulmonary embolism.

• Radiation Oncology Journal
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• v.21 no.1
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• pp.1-9
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• 2003

Purpose : The purpose of this study was to analyze the effect of a Linear accelerator based Photon Knife Radiosurgery System developed by the staff of Keimyung University Dongsan Medical Center for the treatment of cerebral arterlovenous malformation Material and Methods : Between December 1993 and October 2000, 30 patients with cerebral arteriovenous malformation (AVM) were treated with the Linac based Photon knife Radlosurgery System In the Department of Therapeutlc Radiology at Keimyung University Dongsan Medical Center. The median age was 34, ranging from 7 to 63 years, with a 2 : 1 male to female ratio. The locations of the AVM nidi were the frontal lobe (motor cortex), parletal lobe, and the thalamus, In that order. The diameters of the AVM nidi ranged 1.2 to 5.5 cm with a mean on 2.9 cm, and target volumes of between 0.5 and 20.5 cc, with a mean of 5.8 cc. The majority of patients received radiation doses of between 1,500 and 2,500 cGy, w14h a mean of 2,000 cGy, at 80% the isodose line. Twenty-five patients were treated with one isocenter, 4 with two, and 1 with four. The follow-up radiological evaluations were peformed with cranial computed tomogram (CT) or MRI between 6 month and one year interval, and if the AVM nidus had completely disappeared in the CT or MRI, we confirmed thls was a complete obliteration, with a cerebral or magnetic resonance angiogram (MRA). The median iollow-up period was 39 months with a range of 10 to 103 months. Results : Twenty patients were radloiogicaiiy followed up ior over 20 months, with complete obliteration observed in 14 (70%). According to the maximal diameter, all four of the small AVM (<2 cm) completely obliterated, 8 of the 10 patients with a medium AVW (2~3 cm) showed a complete obliteration, and two showed partial obliteration. Among the patients with a large AVM (>3 cm), only one showed complete obliteration, and S showed partial obliteration, but 3 oT these underwent further radiosurgery 3 years later. One who followed up for 20 months fellowing further radiosurgery eventually showed complete obliteration. Ten patients with seizure symptoms had no recurrent seizure due to radiosurgery and medication. One of the eleven patients who suffered intracranlal bleeding developed further bleeding at 9 and 51 months fellowing the radiosurgery although complete obliteration was eventually observed and the patient was managed in hospital then recovered. No patient suffered severe complications fellowing the radiosurgery. Conclusion : The radiosurgery with Linac-based Photon knife radiosurgery system, developed by the staff at our hospital, is a safe and effective treatment for AVM patients having diameters or volumes of less than 3 cm or 10 cm$^{3}$, respectively, located In Inoperable areas or who refused neurosurgery. We suggest that staged AVM radiosurgery may initially be considered, if the AVM target volume is above 10 cm$^{3}$

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.1
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• pp.51-57
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• 2000

With the emergence of laser mapping systems, higher resolution DTM of urban area can be acquired and can be used to generate precise orthoimage. But, when the conventional orthoimage generation methods are applied to the area containing features with height difference such as cliffs, bridges, banks. elevated highways and buildings, they cause problems such as occlusion and double mapping. Therefore, this study proposes a new algorithm by modifying and refining conventional orthoimage generation methods. With this algorithm, areas which have occlusion are detected from the base image using camera orientation parameters and DTM. Also, detected areas are restored using alternative images which does not have occlusion in that area. This study can be distinguished from the other studies in the aspects that the proposed algorithm in this paper doesn't need information on building and that uses DTM data and orientation parameters.

• Childhood Kidney Diseases
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• v.4 no.2
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• pp.170-174
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• 2000

Ureteropelvic junction obstruction and duplicated collecting system are common urologic anomalies in upper urinary system, but they seldom occur in combination. These obstruction can occur in both partial or complete duplicated collecting system. Complete duplication of the ureter may be asymptomatic or recognized when complications develop as a result of reflux into the lower pole ureter or obstruction of the upper pole with an ectopic ureterocele. It is difficult to choose an optimal therapy due to the high variability in function, degree of obsturction, damage and potential fir regeneration in growing kidney. We report our experience of successful surgical interventions in the ureteropelvic junction obstruction of the lower pole with complete duplicated collecting system.

• Journal of the Korean Society of Radiology
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• v.82 no.3
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• pp.626-637
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• 2021

Purpose To explore cerebrovascular reservoir (CVR) and arterial transit time (ATT) changes using acetazolamide-challenged multi-phase arterial spin labeling (MP-ASL) perfusion-weighted MRI in chronic cerebrovascular steno-occlusive disease. Materials and Methods This retrospective study enrolled patients with chronic steno-occlusion who underwent acetazolamide-challenged MP-ASL between June 2019 and October 2020. Cerebral blood flow, CVR, basal ATT, and ATT changes associated with severe stenosis, total occlusion, and chronic infarction lesions were compared. Results There were 32 patients (5 with bilateral steno-occlusion) in our study sample. The CVR was significantly reduced during total occlusion compared with severe stenosis (26.2% ± 28.8% vs. 41.4% ± 34.1%, respectively, p = 0.004). The ATT changes were not significantly different (p = 0.717). The CVR was marginally lower in patients with chronic infarction (29.6% ± 39.1% vs. 38.9% ± 28.7%, respectively, p = 0.076). However, the ATT was less shortened in patients with chronic infarction (-54 ± 135 vs. -117 ± 128 ms, respectively, p = 0.013). Conclusion Acetazolamide-challenged MP-ASL provides an MRI-based CVR evaluation tool for chronic steno-occlusive disease.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.1030-1036
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• 2000

Objective : The aim of this study was to retrospectively analyze the safety and effect of Linac based Photon Knife Radiosugery System(PKRS) for treatment of cerebral arteriovenous malformation. Patients and Methods : The authors analyzed the clinical method and results of ten patients who were followed up more than two years, among the 18 patients who had radiosurgery on arteriovenous malformation from June, 1992, to Dec. 1997, with Linac based Photon knife radiosurgery system(PKRS) which was developed in our hospital. Results : The average age of the patients was 30.4(with the range of 13-49), and the sex was seven males and three females. For the initial clinical symptoms, there were five patients with headache, three with seizure, one with hemiparesis, and one with vomiting. Before the radiosurgery, computed tomography, MRI, and cerebral angiogram were done. For the location of arteriovenous malformation, it was found on six patients of cerebral hemisphere, two of thalamus, one of brainstem, and one of corpus callosum. Regarding the size of nidus, there were seven patients of smaller than 3cm, and three patients of larger than 3cm. Computed tomography, MRI, and cerebral angiogram were done periodically for sixth months, first year, and second year after the radiosurgery of PKRS for the completeness of obliteration. Six cases showed complete obliteration, and four partial obliterations were observed among ten cases, and interestingly, six cases of complete obliteration were observed among seven cases of small AVM of smaller than 3cm(the rate of complete obliteration : 85.7%). All patients tolerated the treatment and no significant complication were seen. Conclusion : In this study, linac based radiosurgery using PKRS onto arteriovenous malformation showed excellent effects, therefore authors believe that it is an ideal method for small sized or deep seated AVM.

• Geotechnical Engineering
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• v.12 no.2
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• pp.85-94
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• 1996

Model pile tests, using a calibration chamber in which the stress state and the relative density can be controlled, were performed in order to study the effects of pile diameter on the plugging rate and bearing capacity of open-ended pile. The model piles used in the test series were devised so that the bearing capacity of an open-ended pile could be measured out into three components. The test results showed that fully plugging depth of an open -ended pile increased with increase in pile diameter and soil density. Moreover, it was found that unit plug capacity decreased with increase in pile diameter, though the penetration ratio or plugging rate of piles was constant. However, the existing formulae for estimation of plug capacity give plug capacity which is constant or increased with increase in pile diameter, when penetration ratio or plugging rate of piles is equal. Thus, it is proposed that the effect of pile diameter as well as plugging rate on bearing capacity of pile must be considered in plug capacity estimation.

• Journal of Veterinary Clinics
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• v.29 no.2
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• pp.181-185
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• 2012

An 11-year-old, intact female Shihtzu showing anuria was diagnosed as a urethral leiomyoma. The tumor occupied and obstructed the urethral lumen. In this report, the urethral tumor and secondary obstruction could be diagnosed via ultrasonography and contrast study such as excretory urography and voiding urethrography. Ultrasonography revealed a hypoechoic, demarcated urethral mass in proximal urethra. Contrast study confirmed the urethral obstruction and ruled out the expansion of the tumor into the urinary bladder. The clinical signs of the dog were completely resolved after removing the urethral mass and urethral anastomosis. Leiomyoma is a benign smooth muscle tumor, and rarely reported in lower urinary tract.