• 한국정밀공학회지
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• 제24권12호
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• pp.36-41
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• 2007

• 한국정밀공학회지
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• 제16권3호통권96호
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• pp.62-71
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• 1999

Integrating micro-machined sensors and actuators on the conventional devices with the copper power lines was incompatible to fabricate the mass produced micro electromechanical system (MEMS) devices. To achieve the compatibility of the wiring method between MEMS parts and devices, we developed the three-dimensional sputter-evaporation system that coats micropatterned thin copper films on the surface of the MEMS element. The system consists of a process chamber, two branch chambers, the substrate holder, and a linear-rotary motion feedthrough. Thin copper film was sputtered and evaporated on the biocompatible polymer, Pellethane$^{circed{R}}$ and silicone, catheter that is 2 mm in diameter and 700 mm in length. The metal film coating technique with three-dimensional thin film sputter-evaporation system was developed to apply the power and signal lines on the micro active endoscope. In this paper, we developed the three-dimensional metal film sputter-evaporation system operated on the low temperature for the biopolymeric substrates used in the medical MEMS devices.

• Journal of Chest Surgery
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• 제28권3호
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• pp.316-319
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• 1995

Systemic emboli occur in approximately one-third of patients with cardiac myxoma. Embolization is common because of the friability of the tumor and intracardiac location. Embolic episodes in young patients with normal sinus rhythm should arouse suspicions of cardiac myxoma in the absence of active endocarditis. We present one case of 17 years old girl having saddle embolism combined with left atrial myxoma. We planned staged operation. First, the emergency thromboembolectomy of aortic bifurcation was performed through bilateral transfemoral approach with use of Forgaty catheter. One week later, the extirpation of myxoma was successfully done with ECC.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2512-2514
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• 1998

The bending actuator using zigzag type shape memory alloy springs has been fabricated and characterized. The small sized actuator with outer diameter of 3.0mm and inner diameter of 2.0mm could be implemented because zigzag type spring has advantages for thin wall type actuator over the coil type spring. The measured characteristics of the fabricated bending actuator show the possibility of practical application to micro active bending catheter.

• Journal of Chest Surgery
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• 제34권9호
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• pp.711-715
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• 2001

배경: 심부정맥 혈전증인 증세발현 초기에 적절히 치료하면 완치될 수 있는 질환이다. 만성 심부정맥 혈전증을 장기 추적해 보면 그 결과가 정맥판막 폐쇄부전증, 정맥성 파행, 울혈성 궤양 및 하지 부종 등의 심각한 합병증을 유발한다는 것을 알 수 있다. 혈전 용해술은 용해제를 직접 원하는 혈전 부위에 주입하는 적극적인 치료방법이다. 이 연구의 목적은 유로키나제를 카테터를 통하여 주입하는 방법으로 급성 심부정맥 혈전증을 치료하여 그 효과를 확인하고자 하였다. 대상 및 방법: 급성 심부정맥 혈전증으로 진단받고, 선택적 혈전 용해술에 금기 사항에 없는 5명의 환자를 대상으로 하였다. 결과: 임상적으로 대부분의 혈전을 녹이는데 성공하였다. 총 혈전용해제 투여시간을 평균 2.0$\pm$0.6일 이었고, 유로키나제 사용량은 평균 590만$\pm$245만 IU였다. May-Therner 증후군으로 진단한 4명의 환자에게 총 5개의 스텐트를 삽입하였다. 시술 후 혈뇨가 2예, 천자부위의 혈종이 1예 등이 있었으나 모두 자연 소실되었다. 결론: 급성 심부정맥 혈전증에서 카테터를 이용한 혈전 용해술은 매우 유용한 치료방법이다.

• Clinical and Experimental Pediatrics
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• 제57권6호
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• pp.257-263
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• 2014

The incidence of people living with congenital heart disease (CHD) has been increasing every year owing to remarkable advances in surgical and catheter intervention techniques and devices, and improved knowledge of critical care for patients with CHD. However, these patients continue to face physical, psychosocial, and environmental challenges, and a number of studies have shown higher rates of depression and anxiety disorders than the general population. To improve psychosocial functioning and quality of life for adults with CHD, health care providers are recommended to inform CHD patients of an accurate diagnosis, and overall treatment process, beginning in adolescence to facilitate a smooth transition from adolescence to adulthood. Active cooperation with psychiatrists, psychologists, social workers, chaplains, and family members is highly recommended to help CHD patients feel normal and optimistic and to promote good social interactions, close family relationships, and a strong sense of coherence.

• Journal of Magnetics
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• 제22권1호
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• pp.162-167
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• 2017

Magnetic spiral-type microrobots, which are driven by a rotating magnetic field, have excellent locomotive abilities, whereas their medical applications are limited in the terms of function, such as the ability to drill in blood vessels. In this study, we propose a new robot with superior applications using a magnetic spiral-type machine. The proposed robot can be applied to stent transportation and installation without a catheter. In particular, the robot can be applied to the cardiovascular system, cerebrovascular disease, and nonvascular stent applications depending on the robot size. The robot consists of two independent spiral-type machines and four magnets in total. We controlled directions of thrust force of the two machines, respectively, for active locomotion with a task. We conducted a preliminary validation of the proposed robot for stent transportation and installation through experimental analyses.

• Pediatric Infection and Vaccine
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• 제28권3호
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• pp.133-143
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• 2021

목적: 본 연구는 신생아중환자실에서 중심정맥관 관련 혈류감염 발생률을 확인하고, 이러한 환자들의 임상적 특성 및 원인균에 대해 분석하여 향후 신생아중환자실 내 혈류감염 예방 및 치료 지침의 기초 자료로 활용하고자 수행되었다. 방법: 2016년 1월부터 2020년 12월까지 분당서울대학교병원 신생아중환자실에 입원한 환자 중 중심정맥관 관련 혈류감염이 발생한 환자들을 대상으로 후향적 의무기록 분석을 하였다. 결과: 5년의 연구 기간동안 총 45명의 환자에게서 53례의 중심정맥관 관련 혈류감염이 확인되었고, 18,622 카테터-일 동안 발생률은 1,000 카테터-일 당 2.85건이었다. 가장 흔한 중심정맥관 종류는 말초 혈관 삽입형 중심정맥관이었다. 총 57균주가 분리되었고, 이 중 그람 양성균, 그람 음성균, 진균이 각각 57.9% (n=33), 36.8% (n=21), 5.3% (n=3)이었다. 가장 흔한 균은 Staphylococcus aureus (n=12, 21%) 와 coagulase-negative staphylococci (n=12, 21%)였고, 그 다음으로는 Klebsiella aerogenes (n=8, 14%)였다. 균혈증 평균 지속시간은 2일이었고, 19건에서는 3일 이상 균혈증이 지속되었다. 균혈증 발생으로부터 14일 이내에 사망한 사례는 총 6건(13.3%)이었다. 결론: 본 연구에서는 신생아중환자실 내 중심정맥관 관련 혈류감염의 발생률과 원인균 분포에 대해 분석하였다. 중심정맥관 관련 혈류감염에 대한 지속적인 모니터링은 경험적 항생제 사용 지침을 수립하기 위한 중요한 기반이 될 수 있으며, 감염예방 지침 실행의 필요성 및 이에 따른 영향을 평가하는 데에 도움이 될 것으로 생각된다.

• Journal of Korean Neurosurgical Society
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• 제46권2호
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• pp.123-129
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• 2009

Objective: This study was aimed to identify the incidence and risk factors of vancomycin-resistant enterococcus (VRE) colonization in neurosurgical practice of field, with particular attention to intensive care unit (ICU). Methods: This retrospective study was carried out on the Neurosurgical ICU (NICU), during the period from January. 2005 to December. 2007, in 414 consecutive patients who had been admitted to the NICU. Demographics and known risk factors were retrieved and assessed by statistical methods. Results: A total of 52 patients had VRE colonization among 414 patients enrolled, with an overall prevalence rate of 6.1%. E. faecium was the most frequently isolated pathogen, and 92.3% of all VRE were isolated from urine specimen. Active infection was noticed only in 2 patients with bacteremia and meningitis. Relative antibiotic agents were third-generation cephalosporin in 40%, and vancomycin in 23%, and multiple antibiotic usages were also identified in 13% of all cases. Multivariate analyses showed Glasgow coma scale (GCS) score less than 8, placement of Foley catheter longer than 2 weeks, ICU stay over 2 weeks and presence of nearby VRE-positive patients had a significantly independent association with VRE infection. Conclusion: When managing the high-risk patients being prone to be infected VRE in the NICU, extreme caution should be paid upon. Because prevention and outbreak control is of ultimate importance, clinicians should be alert the possibility of impending colonization and infection by all means available. The most crucial interventions are careful hand washing, strict glove handling, meticulous and active screening, and complete segregation.

• Journal of Korean Neurosurgical Society
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• 제58권1호
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• pp.76-78
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• 2015

This report details a case of unexpected, severe post-operative cerebral edema following cranioplasty. We discuss the possible pathological mechanisms of this complication. A 50-year-old female was admitted to our department with sudden onset of stuporous consciousness. A brain computed tomography (CT) revealed a subarachnoid hemorrhage with intracranial hemorrhage and subdural hematoma. Emergency decompressive craniectomy and aneurysmal neck clipping were performed. Following recovery, the decision was made to proceed with an autologous cranioplasty. The cranioplasty procedure was free of complications. An epidural drain was placed and connected to a suction system during skin closure to avoid epidural blood accumulation. However, following the procedure, the patient had a seizure in the recovery room. An emergency brain CT scan revealed widespread cerebral edema, and the catheter drain was clamped. The increased intracranial pressure and cerebral edema were controlled with osmotic diuretics, corticosteroids, and antiepileptic drugs. The edema slowly subsided, but new low-density areas were noted in the brain on follow-up CT 1 week later. We speculated that placing the epidural drain on active suction may have caused an acute decrease in intracranial pressure and subsequent rapid expansion of the brain, which impaired autoregulation and led to reperfusion injury.