• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.111-115
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• 1997

The objective of present study is to obtain information about stenosis effects on the blood flow in the coronary artery bifurcation. The three dimensional steady of blood in the coronary artery bifurcation with stenosis and without stenosis are simulated using the finite volume method. Apparent viscosity of blood is represented as a function of shear rate by the Carreau models. Velocities vectors and wall shear stresses along the branch tubes with stenosis are compared with those of without stenosis for steady flows. Flow phenomena in the stenosed branch tubes are discussed extensively.

• Journal of Korean Neurosurgical Society
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• 제40권1호
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• pp.28-30
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• 2006

Two patients presented with amaurosis fugax[AMF]. despite treatment with antiplatelet drugs and anticoagulants due to previous transient ischemic attacks. Angiography demonstrated severe stenosis in the cavernous and petrous internal carotid artery[ICA] respectively, with reduced flow in the ophthalmic artery[OA]. Endovascular stent placement in both patients resulted in normalization of the vessel lumen of the stenotic vessel segments. In addition, complete restoration of OA flow was noted immediately after stenting. Both patients showed no further episode of AMF over a follow-up period of 38 and 23 months respectively. Our clinical and angiographic findings suggest that hemodynamic Insufficiency in retinal vasculature caused by a stenosis of the cavernous or petrous ICA can be treated successfully by endovascular stent.

• Childhood Kidney Diseases
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• 제27권2호
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• pp.117-120
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• 2023

Here, we present the case of a 2-month-old male infant with hyponatremic hypertensive syndrome resulting from stenosis of the right proximal and mid-renal arteries. The patient exhibited nephrotic-range proteinuria, low serum albumin, increased serum creatinine, and elevated renin and aldosterone levels. Doppler ultrasonography and computed tomography angiography revealed decreased vascular flow in the small right renal artery. Following a successful percutaneous balloon angioplasty, the patient experienced a decrease in blood pressure and normalization of serum electrolyte levels within a few days. However, it took 3 months for the proteinuria to resolve completely. This case is significant as it represents the first reported instance of a neonate presenting with clinical features resembling congenital nephrotic syndrome caused by renal artery stenosis that was successfully treated with percutaneous renal angioplasty.

• Journal of Chest Surgery
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• 제28권4호
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• pp.409-411
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• 1995

One patient developing left main coronary stenosis following double valve replacement is reviewed. Angina pectoris developed 5 months postoperatively. Coronary perfusion with a balloon tip perfusion catheter was performed during previous operation and was considered technically satisfactory. Coronary angiography confirmed stenosis of the left main coronary artery. There was no further coronary arterial disease. An anterior approach between the aorta and pulmonary artery to expose the left main coronary artery was used and patch angioplasty was done. Repeat coronary angiography showed a widely patent left main coronary artery with excellent runoff. A careful search for coronary arterial injury should be made in all symptomatic patients following aortic valve replacement.

• Journal of Yeungnam Medical Science
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• 제34권2호
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• pp.279-284
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• 2017

Pulmonary artery sarcoma (PAS) is a rare and fatal disease that often mimics chronic thromboembolic pulmonary hypertension (CTEPH); therefore, diagnosis of PAS is often delayed. Herein, a healthy 74-year-old man was presented with a 4-month history of dyspnea. Chest computed tomography showed wall thickening and stenosis in the main pulmonary artery as well as in both proximal pulmonary arteries. In order to differentiate between unusual CTEPH, vasculitis, and PAS, we performed right heart catheterization and pulmonary angiography. The mean pulmonary arterial pressure was 21 mmHg, and there was severe pulmonary artery stenosis. Thrombi on the pulmonary arterial wall lesions were observed in intravascular ultrasound and optical coherence tomography. Furthermore, the patient had a history of deep vein thrombosis. Therefore, we diagnosed unusual CTEPH. After 6 months of rivaroxaban anticoagulation therapy, a chest X-ray revealed a left lower lobe lung mass, and a positron emission tomography later showed hypermetabolic lesions in the main pulmonary artery wall, in both pulmonary arteries walls, in the lung parenchyma, and in the bones. A biopsy of the right proximal humerus lesion revealed undifferentiated intimal sarcoma. Pulmonary sarcoma is rare, but should be considered when differentially diagnosing main pulmonary artery wall thickening and stenosis. A positron emission tomography may aid in this diagnosis.

• Journal of Chest Surgery
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• 제39권9호
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• pp.706-709
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• 2006

관상동맥 개구부 직접 관류법과 관련된 근위부 관상동맥 협착은 매우 드물게 발생하지만 환자의 생명을 위협할 수 있는 심각한 합병증이다. 저자들은 관상동맥 개구부 직접 관류법과 관련된 근위부 관상동맥 협착을 2000년 9월에 처음 경험한 이후 최근까지 모두 3예를 경험하였기에 보고하는 바이다.

• 대한방사선기술학회지:방사선기술과학
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• 제42권5호
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• pp.351-356
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• 2019

This study aimed to determine whether there was a difference in measurements between North American Symptomatic Carotid Endarterectomy Trial(NASCET) and Warfarin-Aspirin Symptomatic Intracranial Disease(WASID) methods that measure the middle cerebral artery stenosis in Digital Subtraction Angiography (DSA) and Magnetic Resonance Angiography (MRA). It involved 24 patients who had completed both DSA and MRA among patients with Middle Cerebral Artery (MCA) stenosis. The Middle Cerebral Artery (MCA) stenosis was measured using the NASCET and WASID methods through a retrospective analysis. For the NASCET and WASID methods, they performed measurements on normal blood vessels located far from and close to the stenosis, respectively. The mean value and standard deviation of the Digital Subtraction Angiography (DSA) measured by the NASCET method were 59.23% and 13.27%. On the other hand, those of the Digital Subtraction Angiography (DSA) measured by the WASID method were 66.64% and 12.47%. And, the mean value and standard deviation of the Magnetic Resonance Angiography (MRA) measured by the NASCET method were 49.82% and 12.06%. By contrast, those of the Magnetic Resonance Angiography (MRA) measured by the WASID method were 56.63% and 10.67%. All the p-values obtained by the Pearson and Spearman correlation tests in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) were <0.01. In conclusion, this study suggests that both the NASCET and WASID methods to measure the middle cerebral artery stenosis in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) can be used if they are not used interchangeably.

• 대한중풍순환신경학회지
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• 제12권1호
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• pp.50-60
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• 2011

Objectives : This study was aimed to clarify the relationship between the dampness-phlegm diagnosis and internal carotid artery stenosis by measuring carotid artery sonography in cerebral infarction patients. Methods : One hundred eighty subjects were recruited from the patients admitted to the Department of Internal Medicine at Kyunghee university oriental medical center from September 2008 to July 2010. We assessed one hundred eighty patients' carotid artery sonography data and diagnosed dampness-phlegm by oriental medical diagnosis. then, analyzed their characteristics, risk factor, lifestyle, metabolic syndrome, body mass index, Waist/Hip ratio(W/H ratio) and dampness-phlegm diagnosis. Results : On the demographic variables of the patients, age, smoking, W/H ratio and dampness-phlegm group were significantly higher in severe internal carotid artery(ICA) stenosis group than in the control group. According to the significant difference in dampness-phlegm group, we analyzed dampness-phlegm related index for pattern identifications by ICA stenosis. As a result, sputum, bowel sound, chest discomfort, slippery pulse were significantly higher in the severe ICA stenosis group than in the control group. In multivariate analysis, dampness-phlegm group showed close relationship with severe ICA stenosis group. Conclusion : According to the analysis, significance between dampness-phlegm diagnosed patients group and severe ICA stenosis were clarified. These results can be utilized in the future as a basis material.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1999년도 추계 학술대회논문집
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• pp.152-157
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• 1999

For the simulation of the blood flow in coronary artery, the system modeling of coronary hemodynamics is combined with CFD technique. The blood flow in coronary artery interacts with the global coronary circulation. Especially in case of the coronary artery with stenosis, the interaction plays an important role in the hemodynamics of the circulation. In this study we present a combined numerical approach using both the CFD technique for flow simulation and the global system model of coronary circulation. We use a lumped parameter model for the global simulation of coronary circulation whereas the finite element method is employed to compute the viscous flow field in stenosed coronary artery, The time variation of the pressure drop due to stenosis is obtained from the proposed numerical method. Numerical results shows that the flow resistance and pressure drop due to stenosis has a relatively large value in systole.

• Research in Vestibular Science
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• 제17권4호
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• pp.167-169
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• 2018

Rotatory vertebral artery syndrome (RVAS) is characterized by recurrent attacks of vertigo, nystagmus, and syncope induced by compression of the vertebral artery during head rotation. A 60-year-old man with atlas vertebrae fracture presented recurrent attacks of positional vertigo. Left-beat, upbeat and count clock-wise torsional nystagmus occurred after lying down and bilateral head roll (HR) showing no latency or fatigue. Magnetic resonance imaging revealed foramen magnum stenosis (FMS) and dominancy of right vertebral artery (VA). The flow of the right VA on transcranial Doppler decreased significantly during left HR. The slower the velocity was, the more the nystagmus was aggravated. RVAS can be evoked by FMS causing compression of the VA. And the nystagmus might be aggravated according to the blood flow insufficiency.