• The Journal of the Petrological Society of Korea
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• v.22 no.1
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• pp.19-34
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• 2013

The Ipcheon Subbasin is an isolated Miocene basin in SE Korea, which has the geometry of an asymmetric graben elongated in the NE-SW direction. It is in contact with basement rocks by faults and separated from adjacent Waup and Eoil basins by the basement. The strata of the basin fills have an overall homoclinal structure, dipping toward NW or WNW. The basin fills consist of Early Miocene sediments rich in dacitic volcanic and volcaniclastic deposits and Middle Miocene non-volcanic and nonmarine conglomerates intercalated with sand layers, which are distributed in the northeastern and southwestern parts of the basin, respectively. Kinematic analysis of syndepositional conjugate faults in the basin fills indicates WNW-ESE extension of the basin. These features are very similar to those of the adjacent Waup and Eoil basins, indicating that the basin extension was governed by the NE-trending northwestern border faults and that the basin experienced a propagating rifting from NE to SW. Basaltic materials, which occur abundantly in the Eoil Basin, are totally absent in the Ipcheon Subbasin. The observations of the dacitic tuff and tuffaceous mudstone in the subbasin, on slabs and under microscope, suggest that they have lithologies very similar to those of the Yondongri Tuff in the Waup Basin. The Middle Miocene non-volcanic sediments of the Waup and Eoil basins and the Ipcheon Subbasin are distributed consistently in the southwestern part of each basin. It is thus concluded that the extension of the Ipcheon Subbasin began at about 22 Ma together with the Waup Basin and was lulled during the main extension period of the Eoil Basin between 20-18 Ma. At about 17 Ma, the subbasin was re-extended due to the activation of the Yeonil Tectonic Line associated with the propagating rifting toward SW. This event is interpreted to have provided new sedimentation space for the Middle Miocene sediments in the southwestern parts of the Waup and Eoil basins and the Ipcheon Subbasin as well.

• Economic and Environmental Geology
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• v.47 no.4
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• pp.395-404
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• 2014

We conducted the geophysical survey of possible hydrothermal vent sites at 2009, in the Lau Basin, the south western Pacific and analyzed the magnetic characteristics of TA19-1 and TA19-2 seamounts. TA19-1 is a cone-shaped seamount with a caldera summit. TA19-2 seamount is bigger and shows more complicated topography than TA19-1 seamount. TA19-2 has a large caldera, a summit in the west side of the caldera and several crests. Simple dipole anomalies with a high over the north and a low over the south occur in TA19-1 seamount. High magnetic anomalies are located in the northern flank and the summit of TA19-2 seamount and low anomalies around the summit and the caldera. The results of bathymetry and magnetic data suggest that TA19-2 seamount might have more complicated magmatic process than TA19-1. Low magnetization zones are located over the summit, the calderas and the caldera rims. The magnetization lows indicate that submarine hydrothermal vents, along faults and fracture zones, could have caused an alteration of magnetic minerals. The magnetization highs over the summit and the calderas might have been related with later magmatisms like volcanic sills, intrusions.

• Tuberculosis and Respiratory Diseases
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• v.55 no.6
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• pp.551-559
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• 2003

Background : Emergency management in hemoptysis is bronchial artery angiography and embolization. This study was designed to investigate the accuracy of localization of bleeding site by simple roentgenogram, computed tomography(CT) and bronchoscopy prior to embolization and to evaluate the outcome of embolotherapy. Method : We retrospectively evaluated 50 patients performed bronchial artery embolization(BAE), admitted to tertiary university hospital due to hemoptysis. Results : The most common causes were pulmonary tuberculosis, old tuberculous related parenchymal damage, aspergilloma, and bronchiectasis. The success rate of BAE within one month was 90%; within 3 months was 88%; during follow up period of mean 11.6 months was 76%. The concordant rate of simple roentgenogram with angiographic outcome in terms of bleeding site is 70%; in chest CT 80%; in bronchoscopy 81%; in combined information of simple roentgenogram and CT 83%; in combined information of simple roentgenogram and bronchoscopy 78%. Conclusion : The diagnostic accuracy for the bleeding site was similar between chest CT and bronchoscopy, showing high diagnostic yield. The success rate of BAE was comparative to prior studies. Further study will be needed in a large scale in near future.

• The Journal of the Korean bone and joint tumor society
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• v.8 no.3
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• pp.83-89
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• 2002

Purpose: To analyze the postoperative functional and radiographic follow-up results in patients who underwent percutaneous radiofrequency ablation therapy after the diagnosis of osteoid osteoma. Materials and Methods: Seven patients, who were clinically and radiographically diagnosed with osteoid osteoma from July 1999 to January 2001, and received percutaneous radiofrequency ablation therapy. The average follow-up period was 15.5 months(range, 8~25 months). For the diagnosis and accurate localization of the lesion, simple radiography, computed tomography and magnetic resonance imaging(MRI) were performed preoperatively. Simple radiographs and MRI were taken periodically for the follow-up studies. Results: In all 7 patients, symptoms completely disappeared within 3 days after the operation. The average period of hospitalization was 2.4 days, excluding 1 patient who needed an additional burn treatment. The average postoperative night and day pain scores were 1.8 and 1.3, respectively. The average vocational and recreational activity scores were 1 and 0.6, respectively. Conclusions: Satisfactory functional results were obtained with percutaneous radiofrequency ablation therapy for the elimination of osteoid osteoma. Compared to conventional treatment, the advantages of this therapy were short hospitalization period, no internal fixation and bone graft for preventing fracture, and no limitation of joint motion by long fixation period.

• Journal of the Korean Society of Earth Science Education
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• v.9 no.2
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• pp.163-172
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• 2016

The aim of this study is to investigate the geological features distributed in the northwest coast, Goheung Gun as a geological field course of all levels. The study area is about 1.6km coast in direction of northwest from Sumundong ferry to Jangsun beach. The learning contents of the geology units in science textbooks from elementary school to high school was analyzed and, geomorphology and geology of study area was investigated for this study. In this study area, lots of geomorphology and geology elements related to the learning contents of the geology units in science textbooks were founded such as gravel beach, sea cliff, granite, rhyolite, andesite, gneiss, sedimentary rocks, fault, unconformity, stratification, cross bedding, graded bedding, intrusion structure, vein, dyke, plant fossil and spheroidal weathering. Characteristically, strata, stratification, granite, sedimentary rocks(conglomerate, sandstone, mudstone and shale), fault, plant fossil and weathering phenomenon were commonly involved with the learning contents of the geology units in elementary school science, middle school science and high school earth science I, II. This area is to be recommended as a site of geological field course for all students from elementary school to high school, as various field work materials for geological learning were distributed and, geological observation trail of about 400m in length for observation of strata and so on was installed along the coast in direction of the northwest from Sumundong ferry.

• Journal of the Korean Society of Radiology
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• v.81 no.1
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• pp.119-134
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• 2020

It is essential to identify the causative artery in case of active intra-abdominal or gastrointestinal bleeding. A thorough understanding of the basic arterial anatomy is required to identify the causative artery on contrast-enhanced CT angiography and conventional catheter angiography. If one is familiar with the basic arterial anatomy, obtaining access to the bleeding artery will be easier, despite the variations in the origin and course of the vessels. We describe the basic arterial anatomy that will help beginners in diagnostic radiology to identify the blood vessels that can cause active intra-abdominal or gastrointestinal bleeding.

• Economic and Environmental Geology
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• v.39 no.2 s.177
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• pp.129-149
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• 2006

Previously published stratigraphic, sedimentologic, paleontologic, paleomagnetic and geophysical data are reviewed to make an understanding on the tectonic evolution of the Cretaceous Gyeongsang (Kyongsang) basin, southeast Korea. A stratigraphic framework and a tectonic model on the formation and deformation of the Gyeongsang Basin are newly proposed on the basis of integration these data with magmatism and mineralization ages in the basin. A newly proposed stratigraphic framework indicates that strata in the basin can be subdivided into five distinct stratigraphic units that represent pre-rifting, syn-rifting, inversion I, II, and III stages. The Gyeongsang Basin was formed initially as a pre-rifting stage due to north-south extension in the Late Jurassic prior to a syn-riftins stage that resulted from east-west extension during the Early Cretaceous. In the Late Cretaceous, the basin was deformed by three-staged sequential deformation of north-south, northwest-southeast, and east-west compressions. The tectonic history of the basin has been largely controlled by the change of motion of the Izanagi Plate from north to northwest during the Cretaceous. In the early Cretaceous, the Izanagi Plate began to subduct northward beneath the Eurasian Plate and caused the left-lateral strike-slip fault systems in the southern part of the peninsula. The left-lateral wrenching of these fault systems was causally linked to development of pull-apart basins, such as the Gyeongsang Basin in the southeastern part of the peninsula. However, northwestward movement of the Izanagi Plate during the Late Cretaceous probably led to the extensive volcanism as well as sequential deformations in the basin. The stratigraphic and tectonic model, which is newly proposed as a result of this study, may be expected to enhancing the efficiency for exploration and exploitation of useful mineral resources in the basin as well as establishing geologic history in the Cretaceous Gyeongsang Basin. Together with the spatial and temporal correlation of the Cretaceous basins in adjacent areas, this stratigraphic and tectonic model provides a new geologic paradigm to delineate the sophisticated tectonic history of East Asia turing the Cretaceous.

• Tuberculosis and Respiratory Diseases
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• v.44 no.1
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• pp.59-68
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• 1997

Background : Tuberculous chest wall abscess is a rare complication of tuberculosis. However, there have been few reports about the variable extents and shapes of tuberculous chest wall abscesses. We analyzed the extent and shape of tuberculous chest wall abscess-es and grouped them according to combined pleuroparenchymal lesions by CT scans. Materials and Methods : CT findings were evaluated in 20 patients of tuberculous chest wall abscesses. We classified 29 abscesses in 20 patients into three types according to pleuroparnechymal lesions. Type 1 was defined when there was no active pleuroparenchymal lesion, Type 2, when intrathoracic tuberculosis was contacted with chest wall abscess, Type 3, when ipsilateral subpleural nodules were not contacted with chest wall abscess. Results : The type 1 included 6 abcesses in 6 patients. They showed rib and/or costal cartilage destruction in their center. They were relatively large and round. The type 2 included 13 abscesses in 10 patients. The abscesses in contact with pleural lesion or mediastinal lesion were mainly located in the outer muscle layer, and they were relatively large in size. However, the abscesses in contact with parenchymal lesion were mainly located in extrapleural space. They were relatively small and they were longest along the long axis of ribs. The type 3 included 10 abscesses in 6 patients. They were located mainly in the extrapleural space. Conclusion : Tuberculous chest wall abscess-es showed variable extents and shapes according 10 pleuroparenchymal lesions. CT is a good diagnostic modality to visualize the extent of tuberculous chest wall abscess and combined pleuroparenchymal lesion.

• Radiation Oncology Journal
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• v.27 no.2
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• pp.55-63
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• 2009

Purpose: This study was performed to objectively evaluate the rate of tumor response to hypofractionated radiotherapy for advanced squamous cell carcinomas of the head and neck. Materials and Methods: Thirty-one patients with advanced squamous cell carcinoma of the head and neck, who were treated by hypofractionated radiotherapy with 3 Gy per fraction for palliative purpose between 1998 and 2008, were reviewed retrospectively. Every tumor-volume was measured and evaluated from CT (computed tomography) images obtained before and 2~3 months after radiotherapy. The radiation toxicity was assessed during and after radiotherapy. A statistical analysis was performed to investigate overall survival, progressionfree survival, and the prognostic factors for survival and response. Results: The median age of the study patients was 70 years. In addition, 85% of the patients were in stage 4 cancer and 66.7% had an ECOG performance status of 1~2. The mean tumor-volume was 128.4 cc. Radiotherapy was administered with a total dose of 24~45 Gy (median: 36 Gy) over 10~25 days. Twenty-nine patients were treated with 30 Gy or more. The observed complete response rate was 12.9% and the partial response rate was 61.3%. Median survival time was 8.9 months and the 1-year progression-free survival rate was 12.9%. The treatment response rate was confirmed as a prognostic factor in the rate of survival. The primary site, stage, tumor-volume, radiotherapy field and overall radiation-dose showed a significant relationship with survival and treatment response. No grade 4 toxicity was observed during and after radiotherapy. Conclusion: There was an objective tumor-regression in about 74% of patients treated by hypofractionated radiotherapy. Further evaluation is needed to select the appropriate fraction-size and patient who may require the additional radiotherapy.

• Tuberculosis and Respiratory Diseases
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• v.55 no.1
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• pp.31-40
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• 2003

Background : A CT scan is a useful modality for the diagnosis and evaluation of disease activity in patients with pulmonary tuberculosis. However, the CT diagnosis of pulmonary tuberculosis is sometimes difficult in patients with an atypical CT pattern, especially with lobar consolidation mimicking pneumonia. The aim of this study was to evaluate the clinical and CT features of pulmonary tuberculosis, simulating pneumonia, from a CT scan. Materials and Methods : The clinical and CT features in 21 patients, where the CT diagnosis was pneumonia, or the CT differential diagnosis included pneumonia, were retrospectively analyzed. Results : Of the 21 patients, 6 were immunocompromised, 15 presented with fever or leukocytosis and 15 showed positive sputum smear test for acid fast bacilli. Also, 17 of the 21 patients showed a positive sputum culture test. On the CT scan, consolidation was noted in all patients (100%), volume loss of the involved lobe or segment in 12 (57%), bronchogenic spread in 15 (71%), a cavity in 7 (33%) and bronchial wall thickening also in 7 (33%). The location of the consolidation revealed a relatively even distribution, with no specific predilection site. The other associated pulmonary diseases included ARDS, bronchiectasis, severe pulmonary emphysema, idiopathic pulmonary fibrosis and pulmonary alveolar proteinosis. Conclusion : In the immunocompromised patients, or patients with an underlying pulmonary disease, whose CT scans showed pulmonary consolidation, especially in association with findings of bronchogenic spread, a cavity or bronchial wall thickening, meticulous examination for pulmonary tuberculosis is recommended.