• Title/Summary/Keyword: Leakage risk

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Evaluation of the Usefulness for VMAT of multiple brain metastasis using jaw tracking (Jaw tracking을 이용한 다발성 뇌 전이의 용적세기조절회전치료에 대한 유용성 평가)

  • Kim, Tae Won;Yoo, Soon Mi;Jeon, Soo Dong;Yoon, In Ha;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.73-81
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    • 2018
  • Purpose : The aims of this study were to compare and assess the effectiveness of Volumetric Modulated Arc Therapy(VMAT) using jaw tracking(JT) and fixed jaw(FJ) in radiation therapy of multiple brain metastasis. Methode and material : Among the patients with Multiple Brain Metastasis treated with jaw tracking, 10 patients with more than 6 tumors and with the size of radiation field $14{\times}14cm^2$ or more were included. Each Treatment plans with jaw tracking(JT) and fixed jaw(FJ) was established with Eclipse (Ver. 13.6 Varian, USA). Gamma Index (3 mm, 3 % confidence interval - 95 %) and maximum dose difference were measured with an electronic portal imaging device(EPID). The $D_{max}$ and $D_{mean}$ of Organ At Risk(OAR) were assessed and compared, and the Conformity Index(CI) and Homogeneity Index(HI) were evaluated. Result : Evaluating jaw tracking(JT) and fixed jaw(FJ) outcomes, in all cases, Gamma Index met the permissible standard of 3 mm, 3 % confidence intervals of 95 %. The maximum dose difference value from the areas with leaf end transmission was measured at a maximum of 98.4 % and an average of 43.6 % in clockwise(CW), and 67.9 % and 41.0 % for each in Counter-Clockwise(CCW). With jaw tracking, the maximum value of $D_{max}$ for each normal organ in OAR decreased in 15.36 %~74.59 % with the average value decreasing in 2.84 %~39.80 %. The maximum value of $D_{mean}$ in OAR decreased in 27.90 %~65.23 %, with the average value decreasing in 7.70 %~41.71 %. No change has been found in Conformity Index and Homogeneity Index values. Conclusion : When Jaw tracking is used in treating patients with multiple brain metastasis with VMAT, the unnecessary exposure due to leakage and transmission of radiation in unspecified areas was reduced, without affecting the dose distribution of the planning target volume(PTV), and the availability of radiation therapy with lower doses in normal organs is expected.

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Ten Years Experiences of ATS Mechanical Valve (ATS 기계 판막의 10년 임상경험)

  • Yi, Gi-Jong;Bae, Mi-Kyung;Lim, Sang-Hyun;Yoo, Kyung-Jong;Chang, Byung-Chul;Hong, You-Sun
    • Journal of Chest Surgery
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    • v.39 no.12 s.269
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    • pp.891-899
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    • 2006
  • Background: This study is to evaluate the safety of ATS valve by examining the clinical results of ten-years experience. Material and Method: From July 1995 to March 2005, we reviewed 305 patients with ATS valve implantation. Mean age was $49.8{\pm}11.7$ years and 140(45.6%) males were included. Etiologies were rheumatic diseases in 207 cases(67.4%), degenerative changes in 57 cases(18.6%), valve dysfunction in 23 cases(7.5%) and infective endocarditis in 14 cases(4.6%). AVR was performed in 72 patients(23.5%), MVR in 156 patients (50.8%), DVR(AVR+MVR) in 63 patients(20.5%) and TVR in 16 patients(5.2%). Result: There were 9 operative mortalities(2.9%). Follow up period was $56.5{\pm}34.0(0{\sim}115)$ months and 96.4% patients were followed up with 9 late deaths. Five and ten years survival rates were $94.9{\pm}1.3%,\;91.2{\pm}2.3%$ using Kaplan-Meier's methods. Valve related event free survival rates in 5 and 10 years were $90.8{\pm}2.0%$ and $86.9{\pm}3.2%$. There were 16 anticoagulation-related hemorrhages, 6 thromboembolisms, 3 prosthetic valve endocarditis and 1 paravalvular leakage. NYHA class improved after operation(p<0.05). Postoperative echocardiography showed significant decrease in LA size, LVEDD and IVESD(p<0.01). Patients with 19 and 21 mm valve showed significantly higher transvalvular pressure gradient in aortic position(p<0.001, p<0.001). Conclusion: ATS valve showed good hemodynamic results with few valve related complications and thus can be used with acceptable risk.

Epidemic acute interstitial pneumonia in children occurred during the early 2006s (2006년 초에 유행한 소아 급성 간질성폐렴)

  • Cheon, Chong Kun;Jin, Hyun-Seung;Kang, Eun Kyeong;Kim, Hyo Bin;Kim, Byoung-Joo;Yu, Jinho;Park, Seong Jong;Hong, Soo-Jong;Park, June Dong
    • Clinical and Experimental Pediatrics
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    • v.51 no.4
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    • pp.383-390
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    • 2008
  • Purpose : This study was aimed to analyze the clinical characteristics of patients with acute interstitial pneumonia who had presented similar clinical patterns from March to June, 2006 and to describe our experience of treatment and to identify risk factors associated with prognosis. Methods : The clinical characteristics, radiologic and histopathologic findings and response to steroids of 15 patients (non-survival group [n=7] and survival group [control, n=8]) with acute interstitial pneumonia were investigated through the review of medical records. Results : The mean age of the patients was 26 (range: 3-48) months. Cough, cyanosis and fever were frequent symptoms. The most frequent radiologic findings on admission were pneumomediastium and extensive ground glass opacity. Surgical lung biopsy was performed on 8/15 (53.3%) patients and diffuse alveolar damage was found. Mechanical ventilation was applied for 9/15 (60.0%) patients for 40 (range: 1-99) days. Five patients in survival group received steroid treatment and 7 patients in non-survivial group (P=0.20). One patient in survival group received steroid pulse treatment and 4 patients in non-survival group (P=0.12). Seven patients died all of respiratory failure. The survival rate was 53.4%. Conclusion : The patients with acute interstitial pneumonia which occurred on spring 2006 showed high mortality because of rapidly and extensively progressing pulmonary fibrosis and air leakage. Therefore, we should consider surgical lung biopsy and steroid application earlier. We should recognize this acute interstitial pneumonia occurring on spring in domestics and need to investigate the cause and treatment in large scale.

Analysis of Modality and Procedures for CCS as CDM Project and Its Countmeasures (CCS 기술의 CDM 사업화 수용에 대한 방식과 절차 분석 및 대응방안 고찰)

  • Noh, Hyon-Jeong;Huh, Cheol;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.3
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    • pp.263-272
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    • 2012
  • Carbon dioxide, emitted by human activities since the industrial revolution, is regarded as a major contributor of global warming. There are many efforts to mitigate climate change, and carbon dioxide capture and geological storage (CCS) is recognized as one of key technologies because it can reduce carbon dioxide emissions from large point sources such as a power station or other industrial installation. The inclusion of CCS as clean development mechanism (CDM) project activities has been considered at UNFCCC as financial incentive mechanisms for those developing countries that may wish to deploy the CCS. Although the Conference of the Parties serving as the Meeting of the Parties to the UNFCCC's Kyoto Protocol (CMP), at Cancun in December 2010, decided that CCS is eligible as CDM project activities, the issues identified in decision 2/CMP.5 should be addressed and resolved in a satisfactory manner. Major issues regarding modalities and procedure are 1) Site selection, 2) Monitoring, 3) Modeling, 4) Boundaries, 5) Seepage Measuring and Accounting, 6) Trans-Boundary Effects, 7) Accounting of Associated Project Emissions (Leakage), 8) Risk and Safety Assessment, and 9) Liability Under the CDM Scheme. The CMP, by its decision 7/CMP.6, invited Parties to submit their views to the secretariat of Subsidiary Body for Scientific and Technological Advice (SBSTA), SBSTA prepared a draft modalities and procedure by exchanging views of Parties through workshop held in Abu Dhabi, UAE (September 2011). The 7th CMP (Durban, December 2011) finally adopted the modalities and procedures for CCS as CDM project activities (CMP[2011], Decision-/CMP.7). The inclusion of CCS as CDM project activities means that CCS is officially accredited as one of $CO_2$ reducing technologies in global carbon market. Consequently, it will affect relevant technologies and industry as well as law and policy in Korea and aboard countries. This paper presents a progress made on discussion and challenges regarding the issue, and aims to suggest some considerations to policy makers in Korea in order to demonstrate and deploy the CCS project in the near future. According to the adopted modalities and procedures for CCS as CDM project activities, it is possible to implement relevant CCS projects in Non-Annex I countries, including Korea, as long as legal and regulatory frameworks are established. Though Korea enacted 'Framework Act on Low Carbon, Green Growth', the details are too inadequate to content the requirements of modalities and procedures for CCS as CDM project. Therefore, it is required not only to amend the existing laws related with capture, transport, and storage of $CO_2$ for paving the way of an prompt deployment of CCS CDM activities in Korea as a short-term approach, but also to establish the united framework as a long-term approach.

Surgical Treatment of the Congenital Esophageal Atresia (선천성 식도 폐쇄증의 외과적 치료)

  • 최필조;전희재;이용훈;조광조;성시찬;우종수
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.567-572
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    • 1999
  • Background: Surgical correction of the full spectrum of esophageal atresia with tracheoesophageal fistula has improved over the years, but the mortality and morbidity assoiated with repair of these anomalies still remains high. Material and Method: We retrospectively analyzes 27 surgically treated patients with esophageal atresia and tracheoesophageal fistula at Dong-A University Hospital between January 1992 and March 1997. Result: There were 21 male and 6 female patients. Mean birth weight was 2.62$\pm$.385 kg(2.0~3.4 kg). Twenty- four(88.9%) had esophageal atresia with distal tracheoesophageal fistula, and 3(11.1%) had pure esophageal atresia. Four(14.8%) infants were allocated to Waterston risk group A, 18(66.7%) to group B, and 5(18.5%) to group C. In eighteen(66.7%) infants with associated anomalies, cardiovascular anomalies were the most common. Three had a gap length of 3.5 cm or greater(ultra-long gap) between esophageal segments, 7 had 2.0 to 3.5 cm(long gap), 8 had 1.0 to 2.0 cm(medium gap), and 9 had 1 cm or less(short gap) gap length. Among 27 neonates, 3 cases underwent staged operation, late colon interposition was done in 2, and all other 24 cases underwent primary esophageal anastomosis. Oerative mortality was 2/27(7.4%). Causes of death included acute renal failure(n=1), empyema from anastomotic leak(n=1), necrotizing enterocolitis(n=1), sepsis(n=1), insulin-dependent diabetus mellitus(n=1 . There were 4 anastomosis- related complications including stricture in 3, leakage in 1. Mortality was related to the gap length(p<.05). Conclusion: Although the complication rate associated with surgical repair of these anomalies is high, this does not always implicate the operative mortality. The overall survival can be improved by effective treatment for combined anomalies and intensive postoperatve care.

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Clinical Application of Stent-graft in Thoracic Aortic Diseases (흉부 대동맥 질환에서 스텐트-그라프트의 임상적 적용)

  • Kim, Kyung-Hwan;Lee, Cheul;Chang, Ji-Min;Chung, Jin-Wook;Ahn, Hyuk;Park, Jae-Hyung
    • Journal of Chest Surgery
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    • v.34 no.9
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    • pp.698-703
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    • 2001
  • Background: Endovascular stent-graft insertion in aortic diseases is now generally accepted as an attractive alternative treatment modality. We reviewed our clinical experiences of endovascular stent-graft insertion in thoracic aorta. Material and Method: Since 1995, we performed 8 cases of endovasclar stent-graft insertion. Preoperative diagnoses were aortic aneurysms in 4, traumatic aortic ruptures in 3, and ruptured aortic pseudoaneurysm in 1. All procedures were performed in angiography room with the guidance of fluoroscopy. The stent-graft device is a custom-made 0.35mm thickness Z-shaped stainless steel wires, intertwined with each other using polypropylene suture ligation. It is covered with expanded Dacron vascular graft. Result: All procedures were performed successfully. Follow-up studies revealed 2 minimal perigraft leakages. There was no significant leakage or graft migration. 2 patients expired due to multiple organ failure and fungal sepsis. Other survivors(6) are doing well. Conclusion: Endovascular stent-graft insertion is relatively saft and effective treatment modality in the managment of various types of aortic diseases. In may be an effective alternative in aortic diseases of great surgical risk.

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Study on the Consequence Effect Analysis & Process Hazard Review at Gas Release from Hydrogen Fluoride Storage Tank (최근 불산 저장탱크에서의 가스 누출시 공정위험 및 결과영향 분석)

  • Ko, JaeSun
    • Journal of the Society of Disaster Information
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    • v.9 no.4
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    • pp.449-461
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    • 2013
  • As the hydrofluoric acid leak in Gumi-si, Gyeongsangbuk-do or hydrochloric acid leak in Ulsan, Gyeongsangnam-do demonstrated, chemical related accidents are mostly caused by large amounts of volatile toxic substances leaking due to the damages of storage tank or pipe lines of transporter. Safety assessment is the most important concern because such toxic material accidents cause human and material damages to the environment and atmosphere of the surrounding area. Therefore, in this study, a hydrofluoric acid leaked from a storage tank was selected as the study example to simulate the leaked substance diffusing into the atmosphere and result analysis was performed through the numerical Analysis and diffusion simulation of ALOHA(Areal Location of Hazardous Atmospheres). the results of a qualitative evaluation of HAZOP (Hazard Operability)was looked at to find that the flange leak, operation delay due to leakage of the valve and the hose, and toxic gas leak were danger factors. Possibility of fire from temperature, pressure and corrosion, nitrogen supply overpressure and toxic leak from internal corrosion of tank or pipe joints were also found to be high. ALOHA resulting effects were a little different depending on the input data of Dense Gas Model, however, the wind direction and speed, rather than atmospheric stability, played bigger role. Higher wind speed affected the diffusion of contaminant. In term of the diffusion concentration, both liquid and gas leaks resulted in almost the same $LC_{50}$ and ALOHA AEGL-3(Acute Exposure Guidline Level) values. Each scenarios showed almost identical results in ALOHA model. Therefore, a buffer distance of toxic gas can be determined by comparing the numerical analysis and the diffusion concentration to the IDLH(Immediately Dangerous to Life and Health). Such study will help perform the risk assessment of toxic leak more efficiently and be utilized in establishing community emergency response system properly.

Nutritional Components and Their Antioxidative Protection of Neuronal Cells of Litchi (Litchi chinensis Sonn.) Fruit Pericarp (리치 과피의 영양화학 성분 및 항산화성 신경세포 보호효과)

  • Jeong, Hee-Rok;Choi, Gwi-Nam;Kim, Ji-Hye;Kwak, Ji-Hyun;Kim, Yeon-Su;Jeong, Chang-Ho;Kim, Dae-Ok;Heo, Ho-Jin
    • Korean Journal of Food Science and Technology
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    • v.42 no.4
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    • pp.481-487
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    • 2010
  • The nutritional components, antioxidant, and neuroprotective effects of water and a 50% methanol extract from litchi fruit pericarp were investigated. The most abundant mineral, amino acid, and fatty acid were K, proline, and palmitic acid, respectively. In addition, the total water phenolics and 50% methanol extracts were 8.02 and 12.28 mg/g, respectively. The DPPH, ABTS radical scavenging activities and ferric reducing antioxidant power of the water and 50% methanol extracts showed dose-dependent antioxidant activity. In a cell viability assay using MTT, almost all extracts showed a protective effect against $H_2O_2$-induced neurotoxicity, and lactate dehydrogenase leakage was also inhibited by the pericarp extracts. In particular, the 50% methanol extract showed a higher cell membrane protective effect than the water extract at the highest concentration. Consequently, these data suggest that litchi fruit pericarp can be utilized as an effective and safe functional food substances for natural antioxidants and may reduce the risk of neurodegenerative disorders.

A Study on Anastomotic Complications after Esophagectomy for Cancer of the Esophagus : A Comparison of Neck and Chest Anastomosis (식도암 수술후 문합부 합병증에 관한 연구 - 경부문합과 흉부문합 간의 비교-)

  • 이형렬;김진희
    • Journal of Chest Surgery
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    • v.32 no.9
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    • pp.799-805
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    • 1999
  • Background: Leakage, stricture formation, and tumor recurrence at the anastomotic site are serious problems after esophagectomy for cancer of the esophagus or cardia. The prevalence of these postoperative complications may be affected by whether an anastomosis is made in the neck or in the chest, therefore a comparison was made between anastomoses made at these two sites. Material and Method: Between 1987 and 1998, 36 patients with cancer of the esophagus underwent transthoracic esophagectomy with cervical(NA, n=20) or thoracic anastomosis(CA, n=16). The tumors were staged postoperatively(stage IIA, n=13; s tage IIB, n=7; stage III, n=16) and were located in the middle thoracic(n=22) or lower thoracic esophagus and cardia(n=14). Result: The overall operative mortality was 8.3%(5% for NA group, 12.5% for CA group). The anastomotic leak rate for the NA group was 15.0% and 12.5% for the CA group. The anastomotic leak rate differed according to the manual(27.3%) or stapled(8.0%) techniques(p < 0.05). The median proximal resection margins in the NA and CA groups were 9.6 cm and 5.8 cm, and the corresponding rates of anastomotic tumor recurrence were 5.3% and 28.6%(p < 0.05). The prevalence of benign stricture formation (defined as moderate/severe dysphagia) was higher in the NA group(36.8%) than in the CA group(21.4%). When an anastomosis was made by the stapled technique, smaller size of the staple increased the prevalence of stricture formation - 41.7% with 25-mm staple and 9.1% with 28-mm staple(p < 0.05). Conclusion: Wider resection margin could decrease the anastomotic tumor recurrence, and the stapled technique could decrease the anastomotic leak. The prevalence of benign stricture was higher in the cervical anastomosis but the anastomotic leak and smaller size(25-mm) of the staple should be considered as risk factors.

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The Clinical Applicability of Transoral Transpharyngeal Approach to the Craniovertebral Junction Lesions (두개 경추 이행부의 병소에 대한 경구적 접근법의 유용성)

  • Cho, Tae Goo;Park, Kwan;Cho, Yang-Sun;Baek, Chung-Hwan;Nam, Do Hyun;Kim, Jong Soo;Hong, Seung-Chyul;Shin, Hyung Jin;Eoh, Whan;Kim, Jong Hyun
    • Journal of Korean Neurosurgical Society
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    • v.29 no.3
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    • pp.379-388
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    • 2000
  • Objective : Although transoral transpharyngeal approach is a very useful method for the lesions of craniovertebral junction, it is not frequently used because of anatomical unfamilarity, risk of cerebrospinal fluid(CSF) leakage, and resultant postoperative meningitis. To evaluate the usefulness of transoral transpharyngeal approach for various lesions of craniovertebral junction, clinical characteristics and the results of this approach are investigated. Methods : Transoral transpharyngeal approaches were performed in eight cases between 1996 and 1999. Among them, there were three basilar invaginations due to congenital anomalies, two odontoid type I fractures, two atlantoaxial dislocations, and one pseudotumor. Surgical methods included five cases of anterior decompression and posterior fusion, two anterior approaches for decompression and one transoral approach for biopsy. Results : This procedure allowed immediate clinical improvement in all cases. In seven patients with preoperative motor deficit showed a progressive neurological improvement. The follow-up plain x-rays demonstrated successful bony fusion in all patients. Only one patient suffered from postoperative wound dehiscence, but she completely recovered after wound revision. There was no complication of postoperative CSF leakages. Conclusions : Transoral transpharyngeal approach for the ventral lesions of craniovertebral junction, can be used as a relatively simple and effective method.

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