• Title/Summary/Keyword: Magnetic resonance angiography

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The Research to Correct Overestimation in TOF-MRA for Severity of Cerebrovascular Stenosis (3D-SPACE T2 기법에 의한 TOF-MRA검사 시 발생하는 혈관 내 협착 정도의 측정 오류 개선에 관한 연구)

  • Han, Yong Su;Kim, Ho Chul;Lee, Dong Young;Lee, Su Cheol;Ha, Seung Han;Kim, Min Gi
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.12
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    • pp.180-188
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    • 2014
  • It is very important accurate diagnosis and quick treatment in cerebrovascular disease, i.e. stenosis or occlusion that could be caused by risk factors such as poor dietary habits, insufficient exercise, and obesity. Time-of-flight magnetic resonance angiography (TOF-MRA), it is well known as diagnostic method without using contrast agent for cerebrovascular disease, is the most representative and reliable technique. Nevertheless, it still has measurement errors (also known as overestimation) for length of stenosis and area of occlusion in celebral infarction that is built by accumulation and rupture of plaques generated by hemodynamic turbulence. The purpose of this study is to show clinical trial feasibility for 3D-SPACE T2, which is improved by using signal attenuation effects of fluid velocity, in diagnosis of cerebrovascular disease. To model angiostenosis, strictures of different proportions (40%, 50%, 60%, and 70%) and virtual blood stream (normal saline) of different velocities (0.19 ml/sec, 1.5 ml/sec, 2.1 ml/sec, and 2.6 ml/sec) by using dialysis were made. Cross-examinations were performed for 3D-SPACE T2 and TOF-MRA (16 times each). The accuracy of measurement for length of stenosis was compared in all experimental conditions. 3D-SPACE 2T has superiority in terms of accuracy for measurements of the length of stenosis, compared with TOF-MRA. Also, it is robust in fast blood stream and large stenosis than TOF-MRA. 3D-SPACE 2T will be promising technique to increase diagnosis accuracy in narrow complex lesions as like two cerebral small vessels with stenosis, created by hemodynamic turbulence.

Central Nervous System Complications of Coronary Artery Bypass Grafting - Comparison Between Off-Pump CABG and Conventional CABG (관상동맥 우회술 후의 중추신경계 합병증 - 심폐바이패스를 사용하지 않은 관상동맥 우회술과 기존의 관상동맥 우회술의 비교)

  • Chang, Ji-Min;Lee, Jeong-Sang;Kim, Ki-Bong;Ahn, Hyuk;Yoon, Byung-Woo;Kim, Yong-Jin
    • Journal of Chest Surgery
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    • v.33 no.12
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    • pp.941-947
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    • 2000
  • Background: Central nervous system complication after coronary artery bypass grafting(CABG) is one of the major prognostic determinants and the use of the cardiopulmonary bypass(CPB) may increase the incidence of this devastating complication. In this study, the outcomes after off-pump CABG were studied and compared with those following the conventional CABG using CPB. Material and Method: Among the consecutive isolated CABG's performed in SNUH during Feb. 1995 and Jun. 1999, 338 coronary artery bypass grafting were divided into two groups. 223 patients underwent CABG using the CPB(Group I), and 115 patients underwent CABG without CPB(OPCAB)(Group II). All patients enrolled in this study received extensive preoperative examinations including thorough neurologic examination before and after surgery, transcranial doppler study, carotid duplex ultrasonography, and magnetic resonance angiography if necessary. Central nervous system(CNS) complications were defined as stroke, seizure, metabolic or hypoxic encephalopathy and transient delirium after surgery. Result: There were 61 cases(27.3%) who developed postoperative CNS complication in Group I, whereas 8 cases(7.0%) of CNS complications developed postoperatively in group II(p<0.05). Statistically significant predictors of postoperative CNS complications in group I were age and the use of cardiac assist devices perioperatively. Conclusion: This study suggested that omitting the use of CPB in CABG resulted in significant decrease of the postoperative CNS complications. OPCAB should be more widely applied especially to the elderly who have preexisting cerebrovascular disease.

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