• Korean Journal of Remote Sensing
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• v.33 no.5_1
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• pp.469-480
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• 2017

This study aims to understand the relationship between lineaments and epicenters in Geochang region, Gyungsangnam-do, South Korea. An instrumental observation of earthquakes has been started by Korea Meteorological Administration (KMA) since 1978 and there were 6 earthquakes with magnitude ranging 2 to 2.5 in Geochang region from 1978 to 2016. Lineaments were extracted from LANDSAT 8 satellite image and shaded relief map displayed in 3-dimension using Digital Elevation Model (DEM). Then, lineament density was statistically examined by hotspot analysis. Hexagonal grids were generated to perform the analysis because hexagonal pattern expresses lineaments with less discontinuity than square girds, and the size of the grid was selected to minimize a variance of lineament density. Since hotspot analysis measures the extent of clustering with Z score, Z scores computed with lineaments' frequency ($L_f$), length ($L_d$), and intersection ($L_t$) were used to find lineament clusters in the density map. Furthermore, the Z scores were extracted from the epicenters and examined to see the relevance of each density elements to epicenters. As a result, 15 among 18 densities,recorded as 3 elements in 6 epicenters, were higher than 1.65 which is 95% of the standard normal distribution. This indicates that epicenters coincide with high density area. Especially, $L_f$ and $L_t$ had a significant relationship with epicenter, being located in upper 95% of the standard normal distribution, except for one epicenter in $L_t$. This study can be used to identify potential seismic zones by improving the accuracy of expressing lineaments' spatial distribution and analyzing relationship between lineament density and epicenter. However, additional studies in wider study area with more epicenters are recommended to promote the results.

• The Journal of the Korean bone and joint tumor society
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• v.9 no.1
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• pp.69-76
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• 2003

Purpose: This study was designed to provide the data base for the diagnosis and treatment of the foot tumor by investigation of the clinical and pathological characteristics and distribution of the foot tumor. Materials and Methods: 142 foot tumors of 141 patients were studied. All patients were diagnosed with surgical biopsy. We investigated clinical and pathological characteristics and epidemiologic distribution of the foot tumor by reviewing the medical records and imaging materials. The location of the tumors were classified with zone of Kirby et al. Results: 75 patients were female and 66 were male. The average age of the patients was 33.2 years old. Benign soft tissue tumors were the most as 68 cases, and followed by 57 benign bone tumors, 12 malignant soft tissue tumors and 5 malignant bone tumors. Ganglia were the most in benign soft tissue tumors as 36 cases, subungual exostoses in benign bone tumors as 18, squamous cell carcinomas in malignant soft tissue tumors as 7, and metastatic lung cancers in malignant bone tumors as 2. The rate of pain complaints was the highest in malignant bone tumors, the duration of symptom was longest in benign soft tissue tumors, and the size of the tumor was the biggest in malignant bone tumors. Neurological symptoms were found in only 3 benign soft tissue tumors. For the zonal distribution, zone 5 was the most in 59 cases and zone 4 was the least as 10. The most numbers of the benign bone tumors located in zone 5, of benign soft tissue tumors in zone 1, of malignant bone tumors in zone 1 and 2, and of malignant soft tissue tumors in zone 5. The methods of surgical treatment included intralesional or marginal resection, curettage with or without bone graft, toe amputation, below knee amputation and limb salvage. Conclusion: The tumors of the foot were rare and various, and mostly benign (88%), but we can do proper treatment of those tumors without excluding malignant tumors by considering the age of patients, pain, duration of symptom, size of the tumors, and zonal distribution.

• Journal of Korean Orthopaedic Sports Medicine
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• v.8 no.1
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• pp.33-38
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• 2009

Purpose: We wanted to report the clinical characteristics and arthroscopic findings of radial tear in medial meniscus posterior horn insertion, commonly occurs in patient over middle age with documentary review. Materials and Methods: Retrograde study using hospital records was done to 40 cases in 40 patients who visited our hospital and had been performed knee arthroscopic surgery due to medial meniscus posterior horn insertion tear between January, 2005 to April, 2007. Seven cases were male and 33 cases were female with the mean age of 61 (range, 47-80). Trauma history, stage of arthritis, period between pain and operation, MRI findings, clinical symptoms and operation methods were evaluated. Results : Six cases had trauma history while 34 cases didn't. In simple x-ray, using Kellgren-Lawrence classification, 31 cases were between stage 0 and II while 9 cases were stage III. In arthroscopic exam, there were 17 cases of Outerbridge grade IV, 4 cases of grade III, 9 cases of grade II, 9 cases of grade I. The mean duration of pain was 5.3 months. In MRI, at least one finding of cleft in axial or coronal view or ghost sign in sagittal view was found in all cases. The shape of meniscus tears were blunt in 18 cases, transverse in 12 and degenerative tear in 10. Subtotal meniscectomy was performed in 16 cases, partial meniscectomy in 10 cases and meniscal repair in 14 cases. Conclusion : Medial meniscus posterior horn insertion tear occurs in patients over middle age is rarely related to trauma history but causes painful mechanical symptom and usually accompany arthritis. Meniscectomy can be done for the treatment but repair can be considered is some cases. Further study on the treatment result will be needed.

• Clinical and Experimental Pediatrics
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• v.52 no.8
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• pp.904-909
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• 2009

Purpose : The differential diagnosis for a pulmonary nodule is intriguing in cancer patients. Metastasis might be a preferential diagnosis, and yet possibilities of other medical conditions still exist. Pulmonary tuberculosis should be enlisted in the differential diagnosis for a pulmonary nodule in cancer patients in Korea. This study was aimed at analyzing the incidence and clinical features of pulmonary tuberculosis that were misdiagnosed as pulmonary metastasis during radiologic follow-up in pediatric cancer patients. Methods : We retrospectively studied 422 cancer patients less than 18 years old in the Korea Cancer Center Hospital from January 2001 to June 2007. We collected episodes of lung metastasis of primary tumor and tuberculosis during treatment or follow-up, and analyzed medical records. Results : There were 5 cases of tuberculosis confirmed after surgery which were initially regarded as cancer. Two patients had respiratory symptoms such as cough and sputum but the other 3 patients did not. One patient had a family history of tuberculosis. Acid-fast M. tuberculosis was found in one case upon tissue specimen analysis. Two cases were Mantoux positive and the sputum examination was negative in all cases. The polymerase chain reaction for tuberculosis on a pathologic specimen was used to differentiate M. tuberculosis from non-tuberculosis mycobacterium (NTM). It was positive in one case. Lung lesions in one case showed a concurrence of tuberculosis along with lung metastasis. One of these patients died after cancer recurrence. Conclusion : It is necessary to consider the possibility of tuberculosis when a lung mass is newly detected during treatment or follow-up in patients with childhood cancer.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.201-205
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• 2009

Background: Cryosurgery has been used to treat primary malignant pulmonary tumors at our institute since November 2004. In this study we analyzed our treatment results and complication rates. Material and Method: A retrospective study using medical charts and imaging data was conducted involving 17 patients with a total of 17 malignant pulmonary tumors who were treated between November 2004 and March 2007. Fourteen patients were males and 3 were females. The median age of the patients was 64 years (range, $54{\sim}77$ years). The average size of the tumors was 48.8mm (range, $36{\sim}111mm$) in diameter. The patients were followed with chest CT scans 7 days, 1 month, 3 months, and 6 months postoperatively. PET scans were obtained between 6 and 9 months postoperatively. The treatment response was analyzed according to the Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Result: Six months after treatment, 6 tumors (35.3%) showed a complete response, 4 (23.5%) had a partial response, 3 (17.6%) had stable disease, and 4 (23.5%) showed disease progression. In tumors <4 cm in diameter, a complete response was reported in 50% of the tumors. A $x^2$-test showed that in tumors <4 cm in diameter, the p-value for results better than a partial response was 0.034. With respect to procedural complications, there was 1 case of blood-tinged sputum which resolved spontaneously within 1 or 2 days, a spontaneously relieved case of subcutaneous emphysema, and 1 patient with a fever. There were no mortalities and the average hospital stay was 6.3 days. Conclusion: The effects of cryosurgery on primary lung cancer is greatest in patients with small tumors. Considering the facts that cryosurgery is minimally invasive, has a low complication rate, and can be performed repetitively, we believe that it may play an important role in the treatment of high risk lung cancer patients.

• Journal of Chest Surgery
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• v.42 no.1
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• pp.63-71
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• 2009

Background: The treatment of tracheal stenosis includes less invasive bronchoscopic intervention and more invasive segmental resection & anastomosis. Depending on the patient's clinical features, sometimes all these methods are inappropriate. Silicone T-tube stenting has recently been used as an alternative, safe management of tracheal stenosis. We studied the short term and Intermediate term results of using T-tubes in patients with tracheal stenosis, and this tracheal stenosis was caused by various underlying diseases. Material and Method: We retrospectively reviewed 57 patients with tracheal stenosis and who were treated with T-tubes between Jan 1997 and Apr 2007. Based on the patient's medical records and the imaging studies, we evaluated the clinical findings and status of T-tube removal. Result: There was no T-tube related morbidity or mortality in this series. On follow-up, one patient underwent sleeve resection and end-to-end anastomosis. The T-tube could be successfully removed from 13 patients (13/57, 22.8%) without additional interventions. For another four patients, a T-tube was again inserted after removal of the first T-tube due to tracheomalacia or recurrent stenosis. Four patients died of underlying disease and cancer. The patients' gender and previous tracheostomy significantly affected T-tube removal. By contrast, multiple logistic regression analysis identified gender as a predictor of successfully removing a T-tube. Gender (p=0.033) and previous tracheostomy (p=0.036) were the two factors for success or failure of T-tube removal. Conclusion: A T-tube provided reliable patency of a stenotic airway that was caused by any etiology. We have proven that using a T-tube is safe and effective therapy for patients with tracheal stenosis for the short term or the intermediate term.

• Clinical and Experimental Pediatrics
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• v.49 no.11
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• pp.1158-1166
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• 2006

Purpose : The purpose of this study is to make a diagnostic classification and discuss a diagnostic strategy of floppy infants by investigating clinical, neurological, electrophysiological, and genetic analysis of infants admitted to intensive care units with the complaint of hypotonia. Methods : A retrospective study was performed from Jan. 1993 to Dec. 2005 in neonatal and pediatric intensive care units of Seoul National University Children's Hospital. Clinical features and all tests related to hypotonia were investigated. Results : There were 21 cases of floppy infants admitted to intensive care units. Final diagnosis was classified as centra (7 cases[33.3 percent]), peripheral (11 cases [52.4 percent]), and unspecified (3 cases [14.3 percent]). Among the central group, three patients were diagnosed as hypoxic ischemic encephalopathy, two patients as Prader-Willi syndrome, one patient as chromosomal disorder, and one patient as transient hypotonia. Among the peripheral group, four patients were diagnosed as myotubular myopathy, three patients as SMA type 1, two patients as congenital myotonic dystrophy, one patient as congenital muscular dystrophy, and one as unspecified motor-neuron disease. Motor power was above grade 3 on average, and deep tendon reflex was brisk in the central group. Among investigations, electromyography showed 66 percent sensitivity in the peripheral group, and muscle biopsy was all diagnostic in the peripheral group. Brain image was diagnostic in the central group, and Prader-Willi FISH or karyotyping was helpful in diagnosis in central group. Morbidity and mortality was more severe in the peripheral group Conclusion : Classification of diagnosis by clinical characteristics in this study, and application of investigations step by step, may provide an effective diagnostic strategy.

• Progress in Medical Physics
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• v.22 no.2
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• pp.72-78
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• 2011

The aim of this study is to evaluate the patient's setup errors in TomoTherapy (Hi-Art II, TomoTherapy, USA) Bodyfix system (Medical Intelligence, Ele-kta, Schwabmuchen, Germany) pressure in the vacuum compression, depending on and were evaluated. Bodyfix immobilization system and vacuum pressure was compression applied to the patients who received Tomotherapy thoracic and abdominal area, 21 patients were selected and TomoTehpay treatment total 477 of MVCT images were obtained. The translational (medial-lateral: ML, anterior-posterior: AP, superior-inferior: SI directions) and rolling were recorded and analyzed statistically. Using Pearson's product-moment coefficient and One-way ANOVA, the degree of correlation depending on the different vacuum pressure levels were statistically analyzed for setup errors from five groups (p<0.05). The largest average and standard deviation of systematic errors were 6.00, 5.95 mm in the AP and SI directions, respectively. The largest average of random errors were 4.72 mm in the SI directions. The correlation coefficients were 0.485, 0.244, and 0.637 for the ML-Roll, AP-Vector, and SI-Vector, respectively. SI-Vector direction showed the best relationship. In the results of the different degree of vacuum pressure in five groups (Pressure range: 30~70 mbar), the setup errors between the ML, SI in both directions and Roll p=0.00 (p<0.05) were shown significant differences. The average errors of SI direction in the vacuum pressure of 40 mbar and 70 mbar group were 4.78 mm and -0.74 mm, respectively. In this study, the correlation between the vacuum pressure and the setup-errors were statistically analyzed. The fact that setup-errors in SI direction is dependent in vacuum pressure considerly setup-errors and movement of interal organs was identified. Finally, setup-errors, and it, based on the movement of internal organs in Bodyfix system we should apply more than 50 mbar vacuum pressure. Based on the results of this study, it is suggested that accuracy of the vacuum pressure and the quantitative analysis of movement of internal organs and the tumor should be studied.

• Neonatal Medicine
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• v.17 no.2
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• pp.224-231
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• 2010

Purpose: Hospital readmissions have recently increased due to early hospital discharge and increased trends in breast-feeding. Neonatal hyperbilirubinemia can lead to fatal permanent neurological sequelae without appropriate management. Early detection and intervention are critical. We evaluated the clinical features, risk factors, and brain MRI findings of Korean newborns with idiopathic nonhemolytic hyperbilirubinemia to determine the optimal management policy. Methods: A retrospective review of the medical records of 79 newborns with idiopathic nonhemolytic hyperbilirubinemia was performed at the NICU of the Kyungpook National University Hospital from January 2006 to September 2009. All patients were 35 or more weeks of gestation, and their peak level of serum total bilirubin was more than 20 mg/dL. Results: The mean gestational age was $38^{+3}{\pm}1^{+4}$ weeks, and the mean age on admission was 8.8$\pm$4.0 days. The mean body weight (3,105$\pm$479 g) was decreased by 2.8$\pm$6.4 percent compared to the mean birth weight (3,174$\pm$406 g). There were no statistically significant differences for the peak serum bilirubin level or the duration and effects of phototherapy between the patients with and without risk factors, which included: breastfeeding, cephalohematoma, subdural hemorrhage, and/or ABO incompatibility. Patients were grouped according to change of body weight. Group I consisted of patients that gained weight compared to birth weight, and group II of patients that lost weight compared to birth weight. There were significant differences in the peak serum total bilirubin level between the two groups. Thirty nine patients had brain MRI evaluation; 21 patients had bilateral symmetric signal intensity increases in the globus pallidus compared to adjacent corticospinal tract and putamen on T1-weighted images. Conclusion: Bilirubin encephalopathy is preventable with early screening and proper management. Parents require instruction on feeding practices and follow-up to prevent complications from idiopathic nonhemolytic hyperbilirubinemia.

• The Journal of the Korean bone and joint tumor society
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• v.19 no.1
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• pp.1-8
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• 2013

Purpose: Primary bone tumors of hindfoot are uncommon compared with other locations, and there have been few large-group studies. This study was designed to analyze the characteristics and the clinical results of the primary bone tumors of hindfoot. Materials and Methods: Forty five cases in 44 patients who have been diagnosed from 1989 to 2011 were reviewed. The minimum follow-up period was 1 year. We retrospectively reviewed the medical records and images. Results: Twenty six cases were male and 18 cases were female. Mean follow-up period was 33.1 months and mean age was 25.1 years. Forty four cases were benign and 1 case was malignant. Thirty six cases occurred in calcaneus and 9 cases were in talus. The most common benign bone tumor was simple bone cyst (20 cases), followed by intraosseous lipoma (12 cases), and chondroblastoma (4 cases). In calcaneus, there were 18 cases of simple bone cyst, and 12 cases of intrasosseous lipoma. In talus, there were 3 cases of chondroblastoma, 2 cases of simple bone cyst, and 2 cases of intraossesous ganglion. Many patients with hindfoot bone tumors presented with pain, but some were found accidentally. Patients received surgical procedures, such as curettage and bone graft, open reduction and internal fixation, tumor resection, and below knee amputation. Conclusion: Primary bone tumors of hindfoot are rare and can be misdiagnosed as ankle sprain or contusion. Although most are benign, malignant tumors cannot be ruled out, so early diagnosis and appropriate treatment is important.