• Journal of Korean Neurosurgical Society
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• 제30권6호
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• pp.800-804
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• 2001

MMD의 외과적 치료에서 소아에서는 직접 및 간접적인 혈관문합술을 병합하거나 아니면 간접적인 혈관문합술들을 병합하여 시행하는 경향이 있고, 성인에서는 혈관의 직경이나 MMD의 진행속도로 보아 STA-MCA 문합술과 같은 직접적인 수술이 많이 활용되고 있으나, 소아나 성인에서나 모두 공통적으로 보다 넓은 뇌표면에 여러 가지 수술방법을 병합하는 것이 좀더 광범위한 범위에 뇌혈류 공급을 증가 시키는데 도움이 된다고 보는 경향이다. 수술의 적응증은 혈관조영상에서의 나타난 질병의 정도보다는 acetazolamide를 이용한 PET 나 SPECT 검사로서 뇌혈류 예비량에 기준을 두고 있는 현상이 혈류 역학적으로도 합리적인 것으로 보인다. 수술후 합병증을 줄이려면 수술중에 정상탄산, 정상체온, 정상혈압을 유지 시킴과 동시에, 수술직후 통증관리도 철저히 하는 것이 매우 중요하다.

• Journal of Korean Neurosurgical Society
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• 제50권6호
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• pp.492-496
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• 2011

Objective : Direct revascularization surgery is regarded as the most effective method of treatment of adults with moyamoya disease. These patients, however, have a higher risk of perioperative ischemic complications than do patients with atherosclerotic stroke, and are at risk for ischemic complications in the hemisphere contralateral to the one operated on. We investigated the incidence and risk factors for ischemic stroke in the contralateral hemisphere after surgical treatment of adults with moyamoya disease. Methods : We retrospectively reviewed the medical records and results of neuroimaging studies on 79 hemispheres of 73 consecutive patients with adult moyamoya disease ($mean{\pm}SD$ age, $37.96{\pm}11.27$ years; range, 18-62 years) who underwent direct bypass surgery over 6 years. Results : Ischemic complications occurred in 4 of 79 (5.1%) contralateral hemispheres, one with Suzuki stage 3 and three with Suzuki stage 4. Three patients showed posterior cerebral artery (PCA) involvement by moyamoya vessels. Advanced stage of moyamoya disease (Suzuki stages 4/5/6; $p$=0.001), PCA involvement ($p$=0.001) and postoperative hypotension (mean arterial blood pressure <80% of preoperative mean arterial blood pressure) on the first ($p$<0.0001) and second ($p$=0.003) days after surgery were significantly correlated with postoperative contralateral ischemic complications. Conclusion : In patients with advanced moyamoya disease and involvement of the PCA, intentional hypotension can result in ischemic stroke in the hemisphere contralateral to the one operated on. Careful control of perioperative blood pressure is crucial for good surgical results.

• Journal of Communications and Networks
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• 제13권5호
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• pp.518-524
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• 2011

A high assurance IP encryption (HAIPE) compliant protocol accelerator is proposed for military networks consisting of red (or classified) networks and black (or unclassified) networks. The boundary between red and black sides is assumed to be protected via a HAIPE device. However, the IP layer encryption introduces challenges for bandwidth on demand satellite communication. The problems experienced by transmission control protocol (TCP) over satellites are well understood: While standard modems (on the black side) employ TCP performance enhancing proxy (PEP) which has been shown to work well, the HAIPE encryption of TCP headers renders the onboard modem's PEP ineffective. This is attributed to the fact that under the bandwidth-on-demand environment, PEP must use traditional TCP mechanisms such as slow start to probe for the available bandwidth of the link (which eliminates the usefulness of the PEP). Most implementations recommend disabling the PEP when a HAIPE device is used. In this paper, we propose a novel solution, namely broadband HAIPE-embeddable satellite communications terminal (BHeST), which utilizes dynamic network performance enhancement algorithms for high latency bandwidth-on-demand satellite links protected by HAIPE. By moving the PEP into the red network and exploiting the explicit congestion notification bypass mechanism allowed by the latest HAIPE standard, we have been able to regain PEP's desired network enhancement that was lost due to HAIPE encryption (even though the idea of deploying PEP at the modem side is not new). Our BHeST solution employs direct video broadcast-return channel service (DVB-RCS), an open standard as a means of providing bandwidth-on-demand satellite links. Another issue we address is the estimation of current satellite bandwidth allocated to a remote terminal which is not available in DVBRCS. Simulation results show that the improvement of our solution over FIX PEP is significant and could reach up to 100%. The improvement over the original TCP is even more (up to 500% for certain configurations).

• Journal of Chest Surgery
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• 제22권4호
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• pp.609-619
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• 1989

During aortic valve surgery, cardioplegic solution is delivered through direct cannulation of both coronary ostia. Since this approach may cause an intimal injury leading to acute dissection or late ostial stenosis, this study was undertaken to evaluate myocardial protective effect of retrograde perfusion of cardioplegia [RCSP <% RRAP] in 18 clinical cases, which were compared with antegrade perfusion of cardioplegia in 27 clinical cases. This study were investigated 1] cease and return of electromechanical activity after cardioplegia infusion 2] the myocardial temperature during operation 3] the aortic cross clamping time and total bypass time 4] frequency of DC shock for defibrillation 5] need for inotropic drugs after operation 6] electrocardiographic evidence of myocardial infarction or ventricular arrhythmia after operation 7] the enzymes activity during preoperative and postoperative period as an evaluation of myocardial ischemic injury and 8] operative mortality rate The combination of retrograde cardioplegia and topical cooling with ice slush yielded promptly hypothermia of myocardium and shorter aortic cross-clamping time compared with antegrade cardioplegia [P < 0.05]. The temperature of the interventricular septum was maintained below 20oC by continuous perfusion or intermittent perfusion of cold blood cardioplegia and other results were no statistically significant difference between the two methods [P >0.05]. This technique provides clear operative field and avoids some serious complications which are caused by coronary ostial cannulation. These results suggested that the retrograde perfusion of cardioplegia is a simple, safe, and effective means of myocardial protection during open heart surgery.

• Journal of Chest Surgery
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• 제36권10호
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• pp.776-779
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• 2003

기침과 고열을 주소로 8세 남아가 전원되었으며, 과거력상 출생시 작은 크기의 심실 중격결손이 있었다. 심장 초음파 검사상 삼첨판에 10${\times}$6mm 크기의 우종이 있었고 심실중격결손 및 중등도의 삼천판 폐쇄부전이 발견되었다. 혈액 균배양 검사에서는 메티씰린 저항성 황색포도구균이 나왔다. 충분한 항생제 치료에도 불구하고 열이 조절되지 않았으며 폐경색이 진행되었다. 정중 흉골 절개하에 혈전제거술 및 우측폐하엽 절제술을 먼저 시행하였으며, 체외순환 하에 우종제거술, 삼첨판 재건술 및 심실중격결손 폐쇄술을 시행하였다.

• Journal of Chest Surgery
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• 제33권5호
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• pp.428-431
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• 2000

In the mid 1980's, the ITA(internal thoracic artery) graft was clearly recognized to be superior to the sapheonous vein graft in respect to long term patency. Therefore, there has been growing interest in the arterial conduit with the possibility of improving the long term result. We have been performing CABG with GEA since 1998 with the same purpose. For mid-term and long-term follow up, we have been performing postoperative coronary angiography. In this paper, a case of GEA spasm, a purported drawback of this conduit, during postoperative coronary anigiography and relieved by direct infusion of 200$\mu\textrm{g}$ isoket into the GEA is reported. The current case which exemplifies the spastic nature of RGEA is accompanied with coronary angiography.

• Journal of Chest Surgery
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• 제28권9호
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• pp.811-816
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• 1995

Repairs of atrial septal defect utilizing cardiopulmonary bypass were performed in 50 adults, ranging age from 16 to 53 years, since April 1986 up to October 1994. They occupied 38.8% of all adult congenital heart disease operated in the same period. Preoperatively, 16 patients were functional class II, 12 patients class III and 4 patients class IV[New York Heart Association Classification , respectively. Five patients combined with atrial fibrillation and the remainders revealed regular sinus rhythm. Cardiac catheterizations were performed in 43 out of 50 patients, and revealed a systolic pulmonary arterial pressure in excess of 51 mmHg in 4 patients but none had reversed shunt. 40 patients[80% were repaired with patch closure and remainings were repaired with direct closure. 49 patients were followed up for 2 months up to 102 months[average 55 months . A comparison of the preoperative and postoperative functional class demonstrated a mean decrease of one NYHA functional level[2.5$\pm$0.63 to 1.4$\pm$0.56 . There was no operative mortality. One patient died during the follow-up period and the death was unrelated to heart disease. Operative treatment is indicated for repair of atrial septal defect with left to right shunt in the adult patient and a considerable clinical improvement can be anticipitated with low mortality.

• Journal of Chest Surgery
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• 제18권2호
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• pp.265-272
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• 1985

Congenital aneurysm of sinus of Valsalva is one of the rare congenital heart disease, which is usually asymptomatic until rupture. The aneurysm usually ruptures into a cardiac chamber and produces an aorto-intracardiac fistula. Ruptured aneurysm is a grave lesion in that it causes heart failure and subsequent death. If, however, it is discovered in its early stages and operated on properly, it can be corrected with considerable success. Form January 1975 through December 1984, 18 consecutive patients with congenital aneurysm of sinus of Valsalva underwent corrective surgery using total cardiopulmonary bypass in our department of Thoracic Surgery. 1. The incidence was about 0.9% of surgical cases of congenital heart disease during that period. 2. 13 were males and 5 females, with ages ranging 12 years to 52 years. 3. Associated anomalies were VSD in 14, infundibular PS in 1, aberrant muscle band in RVOT in 1, and secondary aortic insufficiency in 9. 4. 17 were suggested to arise from right coronary sinus and 1 from noncoronary sinus; Among 17, 12 ruptured into right ventricle, and one from noncoronary sinus into right atrium. 5. Surgical correction was performed by means of direct suture closure with combined pledget or patch graft after aneurysm resection, and associated lesions were also corrected simultaneously. 6. There was only one case of operative mortality, and all the other patients were relatively uneventful in their follow-up studies.

• Journal of Chest Surgery
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• 제18권2호
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• pp.174-181
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• 1985

From Jun. 1980 to Mar. 1984, 33 cases of atrial septal defect, secundum type, operated at the department of Thoracic and Cardiovascular Surgery, School of Medicine, Keimyung University, were analyzed retrospectively. They were 24.3% of all congenital heart diseases operated in the same period. Among the 33 cases, 17 cases were males and 16 cases were females. Their ages were ranged from 4 to 42 years and cases of over 15 years of age were 60.6%. Main symptoms at admission were exertional dyspnea [69.7%], palpitation [63.6%] and frequent upper respiratory infections [51.5%], but 2 cases [6.1%] were asymptomatic. All 33 cases were operated under the direct vision with cardiopulmonary bypass. All cases were secundum type defect of atrial septal defect and single defect were in 29 cases [90.6%], and oval type defect were in 31 cases [96.9%]. In 7 cases [21.9%], other lesions of cardiovascular system were associated, and the most common lesion was pulmonic valvular stenosis [4 cases; 12.5%]. The defects were closed directly in 27 cases and in 6 cases with Dacron patch. Postoperative complications were occurred in 8 cases [24.2%], and they were pleural effusion, congestive heart failure, and alopecia mainly. One case died due to air embolism postoperatively and operative mortality was 3.1%.

• 대한한의진단학회지
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• 제9권1호
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• pp.131-135
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• 2005

Background and purpose: The measurement of direct current (DC) potential on skin area of meridian has recently been adopted to explore the electrophysiological characteristics of meridian system, But there exists two problems to be explained; the entity of the DC potential to be measured and the characteristics of electrode gel interface of measurement system, It is not clear whether the DC potential reflect, at least hypothetically, the entity of meridian, and if there exist any unstable factor in the DC potential measurement system. Methods: In this study, we designed an electronic circuit model of skin and applied known DC potential sources $({\pm}10.75mV,\;0mV)$ to the electrode interface of the skin model. Results: The result showed that the measured DC potential changed according to the time, and the same phenomenon was observed when the electrode gel was replaced with an electric condenser. It is suggested that the measurement of DC potential on electrode gel interface is very difficult and produces unstable values due to the capacity effect of electrode gel. Conclusion: Further studies on the DC potential evaluation in the context of meridian study should consider and bypass this problem.