高憲立2006-07-262018-07-112006-07-262018-07-112001http://ntur.lib.ntu.edu.tw//handle/246246/23489利用心臟整合逆散射超音波組織特性 (Integrated Backscatter Tissue Characterization)，可以定量分析心肌的生物物理狀態，進而加強雙面超音波心圖在解剖 及功能學上的診斷能力。我們過去的研究己顯示此超音波組織特性在心肌梗塞或缺氧時 有顯著之變化。近年來利用Dobutamine 催迫性超音波心圖來診斷心肌缺氧或存活度已 被廣泛在臨床上使用，而在此催迫狀態下的的超音波組織特性變化亦引起廣泛之注意。 然而在催迫狀態下的局部心肌超音波組織特性變化則仍未明瞭。本研究發現以心臟週期 的整合逆散射超音波組織持性變化來觀察原來平坦無變化之機械功能失全的心肌，在接 受Dobutamine 催迫後，其組織特性之變化能否重新表現週期性之線形變化，端視心肌 之存活度及缺氧度。有病灶之心肌組織在Dobutamine 催迫前。均顯示有平坦化的現象， 但若以低劑量Dobutamine 催迫之仍具存活組織之心肌則趨向正常若為壞死之結痂組織 則無法回復。此方法較傳統催迫性超音波更為客觀，值得臨床應用之推廣。Ultrasonic tissue characterization with integrated backscatter is an objective method to quantitatively define the physical state of the myocardium. To investigate whether backscatter imaging during inotropic stimulation could be used objectively to determine the myocardial viability and ischemia in patients with ischemic heart disease, the backscatter changes were examined in 23 patients with myocardial infarction during dobutamine stress two-dimentional echocardiography. Coronary angiography was performed within 1 to 2 days after the stress test. The results of this study demonstrated that changes in backscatter variability correlated significantly with the wall motion changes in stress echocardiography during dobutamine infusion (p<0.0001). In addition, it was shown that the backscatter changes were significantly different in various types of myocardial tissue. In 23 normal control segments, the ultrasonic backscatter variability was preserved and unchanged during inotropic stimulation (p=NS). In 15 viable infarct zones, restoration or an increase in backscatter variability during low-dose dobutamine infusion was noted, this being lost when ischemia developing during high-dose dobutamine infusion (p<0.01). In 9 non-viable infarct zones, the phase-weighted variation was usually £ 0 and did not change significantly during inotropic stimulation, regardless of the patency of the infarct-related arteries. In 15 remote ischemic myocardial zones, the backscatter variability was preserved at the baseline level, did not changed during low-dose dobutamine infusion, but decreased significantly during high-dose dobutamine stress (p<0.01). In conclusion, dobutamine stress tissue characterization could offer an objective approach for the detection of myocardial viability and ischemia, and might be a useful adjunct to the conventional stress echocardiography.application/pdf92643 bytesapplication/pdfzh-TW國立臺灣大學醫學院內科心肌超音波組織特性變化催迫性超音波心圖心肌缺氧心肌存活度Ultrasonic backscattertissue characterizationinotropic stimulationand ischemic heart diseasereporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/23489/1/892314B002452.pdf