• Title/Summary/Keyword: Associated features

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Risk Factors of Neurologic Complications After Coronary Artery Bypass Grafting (관상동맥 우회수술후 신경계 합병증의 위험인자)

  • Park, Kay-Hyun;Chae, Hurn;Park, Choong-Kyu;Jun, Tae-Gook;Park, Pyo-Won
    • Journal of Chest Surgery
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    • v.32 no.9
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    • pp.790-798
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    • 1999
  • Background: As the early outcome after coronary artery bypass grafting(CABG) has been stabilized, neurologic complication has now become one of the most important morbidity. The aim of this study was to find out the risk factors associated with the neurologic complications after CABG. Material and Method: In 351 patients who underwent CABG, the incidence and features of neurologic complications, with associated perioperative risk factors, were retrospectively reviewed. Neurologic complication was defined as a new cerebral infarction confirmed by postoperative neurologic examination and radiologic studies, or delayed recovery of consciousness and orientation for more than 24 hours after the operation. Result: Neurologic complications occurred in 18 patients(5.1%), of these nine(2.6%) were diagnosed as having new cerebral infarctions(stroke). Stroke was manifested as motor paralysis in four patients, mental retardation or orientation abnormality in four, and brain death in one. Statistical analysis revealed the following variables as significant risk factors for neurologic complications by both univariate and multivariate analyses: cardiopulmonary bypass longer than 180 minutes, atheroma of the ascending aorta, carotid artery stenosis detected by Duplex sonography, and past history of cerebrovascular accident or transient ischemic attack. Age over 65 years, aortic calcification detected by simple X-ray, and intraoperative myocardial infarction were significant risk factors by univariate analysis only. Neither the severity of carotid artery stenosis nor technical modifications such as cannulation of the aortic arch or single clamp technique, which were expected to affect the inciden e of neurologic complications, had significant relationship with the incidence. Conclusion: This study confirmed the strong association between neurologic complications after CABG and atherosclerosis of the arterial system. Therefore, to minimize the incidence of neurologic complications, systematic evaluation focused on atherosclerotic lesions of the arterial system followed by adequate alteration of operative strategy is needed.

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Site Characteristics, and Vegetation Structure, and Dynamics of Forest Communities growing Kalopanax septemlobus (Thunb.ex Murray) Koidz. in Gangwon-do (강원도 음나무 자생 임분의 입지환경, 식생구조 및 동태)

  • 이철호;최영철;김세현;권기원
    • Korean Journal of Plant Resources
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    • v.13 no.3
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    • pp.227-242
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    • 2000
  • Site characteristics, vegetation structure and dynamics of Kalopanax septemlobus forests in Mt. Heungjeong, Mt. Balwang and Mt. Gariwang were studied to provide the information need for national resources conservation and restoration of K. septemlobus forest in Gangwon-do of Korea. The K. septemlobus forests were distributed at 780m to 1,300m in altitude, steep slope, ridges-slope areas with facing northeast to northwest in good nutrition area. The annual diameter growth of those trees ranged 1.60mm to 2.41mm. Forty-three plots(20$\times$20m) were set up at three natural population of Kalopanax septemlobus forest and TWINSPAN method was used for vegetation structure analysis. The result of TWINSPAN ordination show that geographical features played a role in determining community types in the study areas. Community type of the study areas classified into three groups by TWINSPAN; K. septemlobus-Quercux mongolica- Acer mono community(Mt. Balwang), K. septemlobus-Q. mongolica- Tilia amurensis community(Mt. Heungjeong), K. septemlobus-Betula costata-Q. mongolica community(Mt. Gariwang). In most of the K. septemlobus forests, major woody species appeared predominantly were Q. mongolica, T. amurensis, Acer pseudo-sieboldianum, Lindera obtusiloba, A. mono, Magnolia sieboldii, Ulmus davidiana var. japonica. And also, Those species were surveyed in all the areas. Species diversity(H') of investigated areas ranged 0.3124~0.13992 and this value relatively higher than that of other forests with similar site. The range of similarity indices between surveyed areas was 64.1~64.54%. The distribution pattern of Morista's index show that Kalopanax septemlobus distributed randomly in tree and concentrated a few sample plots in subtree layer and shurb layer. K. septemlobus occupied 37.1~58.8% of tree layer story, 8.4~17.6% of subtree layer, 0~0.38% of shurb layer each surveyed area. The association analysis showed that Kalopanax septemlobus positively associated with Betula ermani, Deutzia glabrata, Carpinus cordata, Fraxinus mandshurica and negatively associated with Symplocos chinensis var. pilosa, Styrax obassia, Acer mono, Euonymus macroptera, Ulmus davidiana var. japonica. According to the diameter distribution of Kalopanax septemlobus community, the community of Mt. Gariwang will gradually decline and replaced by Quercus community. The communities of Mt. Heungjeong and Mt. Balwang has its seedlings and saplings, so it may be sustained.

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A Study on the Improvement of Guideline in Digital Forest Type Map (수치임상도 작업매뉴얼의 개선방안에 관한 연구)

  • PARK, Jeong-Mook;DO, Mi-Ryung;SIM, Woo-Dam;LEE, Jung-Soo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.1
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    • pp.168-182
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    • 2019
  • The objectives of this study were to examine the production processes and methods of "Forest Type Map Actualization Production (Database (DB) Construction Work Manual)" (Work Manual) identify issues associated with the production processes and methods, and suggest solutions for them by applying evaluation items to a 1:5k digital forest type map. The evaluation items applied to a forest type map were divided into zoning and attributes, and the issues associated with the production processes and methods of Work Manual were derived through analyzing the characteristics of the stand structure and fragmentation by administrative districts. Korea is divided into five divisions, where one is set as the area changed naturally and the other four areas set as the area changed artificially. The area changed naturally has been updated every five years, and those changed artificially have been updated annually. The fragmentation of South Korea was analyzed in order to examine the consistency of the DB established for each region. The results showed that, in South Korea, the number of patches increased and the mean patch size decreased. As a result, the degree of fragmentation and the complexity of shapes increased. The degree of fragmentation and the complexity of shapes decreased in four regions out of 17 regions (metropolitan cities and provinces). The results indicated that there were spatial variations. The "Forest Classification" defines the minimum area of a zoning as 0.1ha. This study examined the criteria for the minimum area of a zoning by estimating the divided object (polygon unit) in a forest type map. The results of this study revealed that approximately 26% of objects were smaller than the minimum area of a zoning. The results implied that it would be necessary to establish the definition and the regeneration interval of "Areas Changed Artificially and Areas Changed Naturally", and improve the standard for the minimum area of a zoning. Among the attributes of Work Manual, "Species Change" item classifies terrain features into 52 types, and 43 types of them belong to stocking land. This study examined distribution ratios by extracting species information from the forest type map. It was found that each of 23 species, approximately 53% of species, occupied less than 0.1% of Forested land. The top three species were pine and other species. Although undergrowth on unstocked forest land are classified in the terrain feature system, their definition and classification criteria are not established in the "Forest Classification" item. Therefore, it will be needed to reestablish the terrain feature system and set the definitions of undergrowth.

Prediction of Expected Residual Useful Life of Rubble-Mound Breakwaters Using Stochastic Gamma Process (추계학적 감마 확률과정을 이용한 경사제의 기대 잔류유효수명 예측)

  • Lee, Cheol-Eung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.3
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    • pp.158-169
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    • 2019
  • A probabilistic model that can predict the residual useful lifetime of structure is formulated by using the gamma process which is one of the stochastic processes. The formulated stochastic model can take into account both the sampling uncertainty associated with damages measured up to now and the temporal uncertainty of cumulative damage over time. A method estimating several parameters of stochastic model is additionally proposed by introducing of the least square method and the method of moments, so that the age of a structure, the operational environment, and the evolution of damage with time can be considered. Some features related to the residual useful lifetime are firstly investigated into through the sensitivity analysis on parameters under a simple setting of single damage data measured at the current age. The stochastic model are then applied to the rubble-mound breakwater straightforwardly. The parameters of gamma process can be estimated for several experimental data on the damage processes of armor rocks of rubble-mound breakwater. The expected damage levels over time, which are numerically simulated with the estimated parameters, are in very good agreement with those from the flume testing. It has been found from various numerical calculations that the probabilities exceeding the failure limit are converged to the constraint that the model must be satisfied after lasting for a long time from now. Meanwhile, the expected residual useful lifetimes evaluated from the failure probabilities are seen to be different with respect to the behavior of damage history. As the coefficient of variation of cumulative damage is becoming large, in particular, it has been shown that the expected residual useful lifetimes have significant discrepancies from those of the deterministic regression model. This is mainly due to the effect of sampling and temporal uncertainties associated with damage, by which the first time to failure tends to be widely distributed. Therefore, the stochastic model presented in this paper for predicting the residual useful lifetime of structure can properly implement the probabilistic assessment on current damage state of structure as well as take account of the temporal uncertainty of future cumulative damage.

Clinical Features, Diagnosis, Management, and Outcomes of Idiopathic Pulmonary Fibrosis in Korea: Analysis of the Korea IPF Cohort (KICO) Registry

  • Jegal, Yangjin;Park, Jong Sun;Kim, Song Yee;Yoo, Hongseok;Jeong, Sung Hwan;Song, Jin Woo;Lee, Jae Ha;Lee, Hong Lyeol;Choi, Sun Mi;Kim, Young Whan;Kim, Yong Hyun;Choi, Hye Sook;Lee, Jongmin;Uh, Soo-Taek;Kim, Tae-Hyung;Kim, Sang-Heon;Lee, Won-Yeon;Kim, Yee Hyung;Lee, Hyun-kyung;Lee, Eun Joo;Heo, Eun Young;Yang, Sei Hoon;Kang, Hyung Koo;Chung, Man Pyo;Korea ILD Study Group,
    • Tuberculosis and Respiratory Diseases
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    • v.85 no.2
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    • pp.185-194
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    • 2022
  • Background: The Korea Interstitial Lung Disease Study Group has made a new nationwide idiopathic pulmonary fibrosis (IPF) registry because the routine clinical practice has changed due to new guidelines and newly developed antifibrotic agents in the recent decade. The aim of this study was to describe recent clinical characteristics of Korean IPF patients. Methods: Both newly diagnosed and following IPF patients diagnosed after the previous registry in 2008 were enrolled. Survival analysis was only conducted for patients diagnosed with IPF after 2016 because antifibrotic agents started to be covered by medical insurance of Korea in October 2015. Results: A total of 2,139 patients were analyzed. Their mean age at diagnosis was 67.4±9.3 years. Of these patients, 76.1% were males, 71.0% were ever-smokers, 14.4% were asymptomatic at the time of diagnosis, and 56.9% were at gender-age-physiology stage I. Occupational toxic material exposure was reported in 534 patients. The mean forced vital capacity was 74.6% and the diffusing capacity for carbon monoxide was 63.6%. Treatment with pirfenidone was increased over time: 62.4% of IPF patients were treated with pirfenidone initially. And 79.2% of patients were treated with antifiboritics for more than three months during the course of the disease since 2016. Old age, acute exacerbation, treatment without antifibrotics, and exposure to wood and stone dust were associated with higher mortality. Conclusion: In the recent Korean IPF registry, the percentage of IPF patients treated with antifibrotics was increased compared to that in the previous IPF registry. Old age, acute exacerbation, treatment without antifibrotics, and exposure to wood and stone dust were associated with higher mortality.

Machine Learning Based MMS Point Cloud Semantic Segmentation (머신러닝 기반 MMS Point Cloud 의미론적 분할)

  • Bae, Jaegu;Seo, Dongju;Kim, Jinsoo
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.939-951
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    • 2022
  • The most important factor in designing autonomous driving systems is to recognize the exact location of the vehicle within the surrounding environment. To date, various sensors and navigation systems have been used for autonomous driving systems; however, all have limitations. Therefore, the need for high-definition (HD) maps that provide high-precision infrastructure information for safe and convenient autonomous driving is increasing. HD maps are drawn using three-dimensional point cloud data acquired through a mobile mapping system (MMS). However, this process requires manual work due to the large numbers of points and drawing layers, increasing the cost and effort associated with HD mapping. The objective of this study was to improve the efficiency of HD mapping by segmenting semantic information in an MMS point cloud into six classes: roads, curbs, sidewalks, medians, lanes, and other elements. Segmentation was performed using various machine learning techniques including random forest (RF), support vector machine (SVM), k-nearest neighbor (KNN), and gradient-boosting machine (GBM), and 11 variables including geometry, color, intensity, and other road design features. MMS point cloud data for a 130-m section of a five-lane road near Minam Station in Busan, were used to evaluate the segmentation models; the average F1 scores of the models were 95.43% for RF, 92.1% for SVM, 91.05% for GBM, and 82.63% for KNN. The RF model showed the best segmentation performance, with F1 scores of 99.3%, 95.5%, 94.5%, 93.5%, and 90.1% for roads, sidewalks, curbs, medians, and lanes, respectively. The variable importance results of the RF model showed high mean decrease accuracy and mean decrease gini for XY dist. and Z dist. variables related to road design, respectively. Thus, variables related to road design contributed significantly to the segmentation of semantic information. The results of this study demonstrate the applicability of segmentation of MMS point cloud data based on machine learning, and will help to reduce the cost and effort associated with HD mapping.

The Effects of Self-regulatory Resources and Construal Levels on the Choices of Zero-cost Products (자아조절자원 및 해석수준이 공짜대안 선택에 미치는 영향)

  • Lee, Jinyong;Im, Seoung Ah
    • Asia Marketing Journal
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    • v.13 no.4
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    • pp.55-76
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    • 2012
  • Most people prefer to choose zero-cost products they may get without paying any money. The 'zero-cost effect' can be explained with a 'zero-cost model' where consumers attach special values to zero-cost products in a different way from general economic models (Shampanier, Mazar and Ariely 2007). If 2 different products at the regular prices of ₩200 and ₩400 simultaneously offer ₩200 discounts, the prices will be changed to ₩0 and ₩200, respectively. In spite of the same price gap of the two products after the ₩200 discounts, people are much more likely to select the free alternative than the same product at the price of ₩200. Although prior studies have focused on the 'zero-cost effect' in isolation of other factors, this study investigates the moderating effects of a self-regulatory resource and a construal level on the selection of free products. Self-regulatory resources induce people to control or regulate their behavior. However, since self-regulatory resources are limited, they are to be easily depleted when exerted (Muraven, Tice, and Baumeister 1998). Without the resources, consumers tend to become less sensitive to price changes and to spend money more extravagantly (Vohs and Faber 2007). Under this condition, they are also likely to invest less effort on their information processing and to make more intuitive decisions (Pocheptsova, Amir, Dhar, and Baumeister 2009). Therefore, context effects such as price changes and zero cost effects are less likely in the circumstances of resource depletion. In addition, construal levels have profound effects on the ways of information processing (Trope and Liberman 2003, 2010). In a high construal level, people tend to attune their minds to core features and desirability aspects, whereas, in a low construal level, they are more likely to process information based on secondary features and feasibility aspects (Khan, Zhu, and Kalra 2010). A perceived value of a product is more related to desirability whereas a zero cost or a price level is more associated with feasibility. Thus, context effects or reliance on feasibility (for instance, the zero cost effect) will be diminished in a high level construal while those effects may remain in a low level construal. When people make decisions, these 2 factors can influence the magnitude of the 'zero-cost effect'. This study ran two experiments to investigate the effects of self-regulatory resources and construal levels on the selection of a free product. Kisses and Ferrero-Rocher, which were adopted in the prior study (Shampanier et al. 2007) were also used as alternatives in Experiments 1 and 2. We designed Experiment 1 in order to test whether self-regulatory resource depletion will moderate the zero-cost effect. The level of self-regulatory resources was manipulated with two different tasks, a Sudoku task in the depletion condition and a task of drawing diagrams in the non-depletion condition. Upon completion of the manipulation task, subjects were randomly assigned to one of a decision set with a zero-cost option (i.e., Kisses ₩0, and Ferrero-Rocher ₩200) or a set without a zero-cost option (i.e., Kisses ₩200, and Ferrero-Rocher ₩400). A pair of alternatives in the two decision sets have the same price gap of ₩200 between a low-priced Kisses and a high-priced Ferrero-Rocher. Subjects in the no-depletion condition selected Kisses more often (71.88%) over Ferrero-Rocher when Kisses was free than when it was priced at ₩200 (34.88%). However, the zero-cost effect disappeared when people do not have self-regulatory resources. Experiment 2 was conducted to investigate whether constual levels influence the magnitude of the 'zero-cost effect'. To manipulate construal levels, 4 different 'why (in the high construal level condition)' or 'how (in the low construal level condition)' questions about health management were asked. They were presented with 4 boxes connected with downward arrows. In a box at the top, there was one question, 'Why do I maintain good physical health?' or 'How do I maintain good physical health?' Subjects inserted a response to the question of why or how they would maintain good physical health. Similar tasks were repeated for the 2nd, 3rd, and 4th responses. After the manipulation task, subjects were randomly assigned either to a decision set with a zero-cost option, or to a set without it, as in Experiment 1. When a low construal level is primed with 'how', subjects chose free Kisses (60.66%) more often over Ferrero-Rocher than they chose ₩200 Kisses (42.19%) over ₩400 FerreroRocher. On contrast, the zero-cost effect could not be observed any longer when a high construal level is primed with 'why'.

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A Study on BRCA1/2 Mutations, Hormone Status and HER-2 Status in Korean Women with Early-onset Breast Cancer (젊은 한국인 유방암 환자에서 BRCA1/2 돌연변이와 호르몬 수용체, HER-2 상태에 관한 연구)

  • Choi, Doo-Ho;Jin, So-Young;Lee, Dong-Wha;Kim, Eun-Seog;Kim, Yong-Ho
    • Radiation Oncology Journal
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    • v.26 no.1
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    • pp.65-73
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    • 2008
  • Purpose: Women with breast cancer diagnosed at an age of 40 years or younger have a greater prevalence of germline BRCA1 and BRCA2 mutations than the prevalence of women with breast cancer diagnosed at older ages. Several immunohistochemical characteristics have been identified in breast cancers from studies of Caucasian women with BRCA1/2 mutations having familial or early-onset breast cancers. The aim of this study is to determine whether early-onset breast cancer in BRCA1 or BRCA2 mutation carriers, who were not selected from a family history, could be distinguished by the use of immunohistochemical methods and could be distinguished from breast cancer in women of a similar age without a germline BRCA1 or BRCA2 mutation. We also analyzed the prognostic difference between BRCA1/2 related and BRCA1/2 non-related patients by the use of univariate and multivariate analysis. Materials and Methods: Breast cancer tissue specimens from Korean women with early-onset breast cancers were studied using a tumor tissue microarray. Immunohistochemical staining of estrogen receptor(ER), progesterone receptor(PR) and HER-2, as well as the histology and grade of these specimens, were compared. The prognostic impact of immunohistochemical and histological factors as well as the BRCA1/2 mutation status was investigated separately. Results: There were 14 cases and 16 deleterious BRCA1/2 mutations among 101 patients tested. A family history(4/14) and bilateral breast cancers(3/9) were high risk factors for BRCA1/2 mutations. BRCA1/2-associated cancers demonstrated more expression of ER-negative(19.4% versus 5.1%, p=0.038) and HER-2 negative than BRCA1/2 negative tumors, especially for tumors with BRCA1 tumors The BRCA1/2 mutation rate for patients with triple negative tumors(negative expression of ER, PR and HER-2) was 24.2%. Tumor size, nodal status, and HER-2 expression status were significantly associated with disease free survival, as determined by univariate and multivariate analysis, but the BRCA1/2 status was not a prognostic factor. Conclusion: Breast cancer that occurs in women with a germline BRCA1 or BRCA2 mutations have recognizable immunohistochemical features, which may be useful in identifying individuals that are more likely to carry germline mutations. Although the BRCA1/2 mutation status was not a prognostic factor in Korean women with early-onset breast cancer, more cases with a longer follow-up period are needed for further study.

Clinical manifestations and neuroimaging findings of schizencephaly in children (소아 뇌갈림증의 신경영상학적 소견 및 임상 양상)

  • Lee, Jae Rang;Kim, Seung;Lee, Young Mock;Lee, Joon Soo;Kim, Heung Dong
    • Clinical and Experimental Pediatrics
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    • v.52 no.4
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    • pp.458-463
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    • 2009
  • Purpose : Schizencephaly is a uncommon congenital brain anomaly characterized by congenital clefts spanning the cerebral hemispheres from pial surface to lateral ventricles and lined by gray matter. In this study, we investigated the clinical manifestation and radiologic findings of pediatric schizencephaly. Methods : The data of 13 patients who were diagnosed with schizencephaly in Severance Childrens Hospital and Yongdong Severance Hospital from January 2005 to December 2007 were analyzed retrospectively. Results : The mean age at diagnosis was $9.08{\pm}2.67$ months old and ranged from 1 to 30 months. The ratio of male to female patients was 3.33:1. Five (38.5%) patients had bilateral clefts, while 8 (61.5%) had unilateral clefts. Five (38.5%) patients had closed lip clefts, and 4 (30.8%) had opened lip clefts. Four (30.8%) patients had multiple clefts. Associated anomalies showed in all cases. The clinical features consisted of mild unilateral weakness in 7 (53.8%) cases and a hemiparesis was present in 3 (23.1%) patients. A tetraparesis was in 3 (23.1%) patients. There was no difference in motor deficit between unilateral and bilateral clefts. Delayed development was observed in all cases. Epilepsy was present in 7 (53.8%) patients, 5 patients with unilateral clefts and 2 patients with bilateral clefts. Three (42.8%) patients showed intractable seizures. Conclusion : Schizencephaly showed variable clinical manifestations and radiologic findings in association with the types and locations of the clefts. It is necessary to diagnose schizencephaly early and to detect the development of epilepsy. Intensive and large studies of the correlation of clinical outcomes and radiologic findings should be continued for more effective treatment.

Clinical Analysis of Contralateral Bulla of Lung on HRCT in the Patients Having Video-Assisted Thoracoscopic Surgery for Unilateral Primary Spontaneous Pneumothorax (자연 기흉 수술 환자에서 반대편 폐기포에 대한 임상적 고찰)

  • Shin, Dong-Il;Oh, Tae-Yoon;Chang, Woon-Ha;Kim, Jung-Tae;Jeong, Young-Kyun
    • Journal of Chest Surgery
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    • v.43 no.6
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    • pp.687-693
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    • 2010
  • Background: It is controversial whether the presence of bullae on the contralateral lung on HRCT plays a role in occurrence of contralateral primary spontaneous pneumothorax. We analyzed the significance of bullae on the contralateral lung and the risk factors associated with contralateral occurrence of primary spontaneous pneumothorax. Material and Method: Three hundred ninety four patients who were undergone Video-Assisted Thoracoscopic Surgery for primary spontaneous pneumothorax between January 2004 and December 2009 were reviewed. The clinical features, HRCT and treatment of these patients were analyzed retrospectively. Result: Twenty eight of 394 patients had contralateral occurrence (7.10%). The average time was $13.06{\pm}9.79$ months. A presence of contralateral bullae of lung on HRCT may not seem to be significant for occurrence of contralateral primary spontaneous pneumothorax (p=0.059). But bullae numbers were much more in contralateral pneumothorax patients (p=0.011). Younger than 20, being underweight (Body Mass Index < $18.5 kg/m^2$) are independent risk factors for contralateral occurrence (odds ratio, 5.075 (1.679~5.339), 2.366 (1.048~5.339) respectively). Conclusion: The presence of bullae on the contralateral lung on HRCT was not significantly influenced the occurrence of contralateral primary spontaneous pneumothorax. However, age, body mass index, and the number of bullae were significant factors for the contralateral pneumothorax. We suggest that those high risk patients may require special attentions and general supportive care to prevent occurrence of contralateral primary spontaneous pneumothorax during the follow-up.