• Clinical Endoscopy
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• v.56 no.5
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• pp.592-593
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• 2023

• Journal of Korean Neurosurgical Society
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• v.38 no.2
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• pp.132-135
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• 2005

We report two cases of patients with ruptured vertebral artery dissecting aneurysms that were treated using double overlapping stent placement. Angiography performed immediately after the procedure revealed a significant reduction of aneurysmal filling due to the intraaneurysmal thorombosis. In one case, complete disappearance of the lesion was observed after seven days and in the another one, the size of previous aneurysm sac was decreased on 7th post-procedure day. The reduced stent porosity caused by the overlapping stents, which result in significant hemodynamic changes inside aneurysmal sac, may accelerate intraanuerysmal thromobosis and may be helpful in achieving a more rapid complete occlusion of aneurysm. This double stent method may represent a therapeutic alternatives for dissecting vertebral artery aneurysm in which conventional endovascular techniques or stent supported coil embolization is not considered feasible and surgical treatment is contraindicated.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.529-532
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• 2013

Cholangiocarcinoma, though very rare in Western countries, is one of the commonest liver malignancies in Southeast Asia, especially in Thailand. More than half of the patients present with advanced stage disease. Given the poor treatment outcomes of adjuvant therapeutic options, many patients undergo only biliary drainage for palliative treatment. Clinical characteristics and treatment outcomes after biliary stenting were here analyzed for a total of 224 uresectable cholangiocarcinoma cases, 58.9% in men. The mean age was 61.5 years. Hilar involvement was the most common location. The patients underwent biliary drainage using plastic and metallic stents equally, early stent occlusion being encountered in 21.4% and 10.7%, respectively. The median survival time was 4.93 months for patients who received plastic and 5.87 months for patients who received metallic stents.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.485-490
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• 2003

In this paper, a nonlinear finite-element method was employed to analyze mechanical behaviors of the balloon-expandable stent. Beyond safety considerations, this type of analysis provides mechanical properties that are often difficult to obtain by experiments. Mechanical properties of the stent expansion pressure, radial recoil, longitudinal recoil and foreshortening were studied using commercial FEM code, ANSYS. As a result, the pressure necessary to expand the stent up to a diameter of 3mm was 7.6atm, longitudinal recoil, radial recoil and foreshortening were -0.388%, 2.87% and 4.07% respectively. In conclusion, a finite element model used in this study could help in designing new stents or analyzing actual stents.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1306-1309
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• 2003

In the present paper, finite element analyses were carried out to evaluate the most important feature of a stent, that is. high radial strength and flexibility. Palmaz-Schatz 154 stent and two new models(stent A, stent B) were selected because they are the most representatives of tubular stents. Finite element analyses for the stent system were performed using ABAQUS/Explicit code. As a result, Palmaz-Schatz 154 stent shows sufficient radial strength but it needs some improvement in general properties such as high flexibility, low elastic recoil, low longitudinal contraction and low metal coverage area. Other two models show that sufficient flexibility, foreshortening and longitudinal recoil.

• Biomaterials and Biomechanics in Bioengineering
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• v.1 no.3
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• pp.131-150
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• 2014

Vascular stenting has a great attention as a treatment for coronary arteries diseases as compared with percutaneous balloon angioplasty. In-stent restenosis and thrombosis are side effects resulting from using bare metal stent (BMS). Employing platelet therapy allowed to reduce the rate of thrombosis, however, the rate of restenosis remains a major problem. In 2002, drug-eluting stents (DESs) were introduced as an effort to reduce the restenosis. The commercially available DESs continue to suffer from coating defects that might lead to a series of adverse effects. Most importantly, multiple concerns remain regarding the polymer coating integrity on metal surfaces or the relation of polymer irregularities to longterm adverse events.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.106-112
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• 2006

Tissue hyperplasia is one of the most frequently encountered complications when self-expanding metallic stents are placed in benign non-vascular luminal organ strictures, thus causing restenosis of the lumen. The investigators postulated that ionizing irradiation could be applied to prevent restenosis caused by tissue hyperplasia in non-vascular luminal organs as it reduced coronary or peripheral arterial narrowing successfully. The authors combined $\beta$-irradiation using $^{188}Re-MAG_3$ solution with balloon dilation for animal and clinical studies because this new treatment approach had the advantages such as low penetration depth of $\beta$-ray, self-centering irradiation, and mechanical effect of balloon dilation over using $\gamma$-irradiation with afterloading devices in this article, the concept and mechanism of radioisotope balloon dilation, and animal and clinical studies using radioisotope balloon dilation are reviewed.

• Journal of Medicine and Life Science
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• v.20 no.3
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• pp.131-134
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• 2023

Here, we present a case of a 56-year-old man with acute myocardial infarction. The patient underwent percutaneous coronary intervention (PCI) at the left main bifurcation and mid-left anterior descending artery using drugeluting stents. Four months after the PCI, the patient was readmitted for cardiac arrest. Coronary angiography (CAG) revealed stent thrombosis in the left main-to-proximal left anterior descending artery and in-stent restenosis in the left main-to-proximal left circumflex artery. We performed balloon angioplasty at the left main to mid-left anterior descending artery and left main to proximal left circumflex artery stents; subsequently, blood flow was fully restored. However, contrast agent extravasation was observed outside the mid-portion of the left main artery to the proximal left anterior descending artery stent, indicating the presence of a coronary artery aneurysm (CAA) outside the stent. After guideline-directed medical therapy with dual antiplatelet agents and high-intensity statins, follow-up CAG revealed near-resolution of the CAA, absence of stenotic lesions, and good blood flow.

• Korean Circulation Journal
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• v.48 no.11
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• pp.1030-1031
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• 2018

• Clinical Endoscopy
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• v.57 no.2
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• pp.193-195
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• 2024