Diagnostic and Therapeutic Utilization of Microbubbles

微泡(Microbubbles)在診斷及治療上的應用

Thomas R. Porter

《Acta Cardiologica Sinica》 21卷2期 (2005/06) Pp. 77-88

摘要

在進行催迫性心臟超音波檢查時，利用靜脈注射微泡(microbubbles)配合心肌顯影超音波(myocardial contrast echocardiography)檢查，能夠有效的偵測出心肌灌注異常的部位。近年來，憑藉即時呈現低功率頻序譜(low mechanical index pulse sequence schemes)技術的發展，甚至能夠讓臨床醫師在進行藥物催迫性超音波檢查時，同步的偵測出心肌收縮及灌注的異常。對於急性心肌梗塞及慢性冠狀動脈心臟病，使用靜脈注射微泡配合心肌顯影超音波檢查，也有助於判斷收縮異常部位的心肌存活度(viability)。微泡由於體積極小，因此可以自由的經由血管循行全身。而若某處血管的內皮細胞功能異常時，微泡即會附著於該處。利用微泡的此種特性，或可將藥物或基因結合於微泡表面，而選擇性的讓有內皮細胞異常的欲治療部位之藥物或基因濃度提高。利用超音波能量擊破微泡亦可能有助於局部藥物釋放及血管內血栓溶解。

關鍵字

心肌顯影超音波 ； 藥物釋放 ； 血栓溶解

並列摘要

Myocardial contrast echocardiography (MCE) is rapidly becoming a technique that can be utilized with intravenous microbubbles to detect myocardial perfusion abnormalities during stress echocardiography. Real-time techniques with low mechanical index pulse sequence schemes have been developed that allow for the simultaneous detection of wall motion and perfusion during pharmacologic stress echocardiography. MCE is also very helpful in determining the viability of the dysfunctional myocardium in the setting of acute myocardial infarction, and in the setting of chronic coronary artery disease. Microbubbles normally pass freely through the large and small vessels, but do adhere to the endothelium in the setting of endothelial dysfunction. This may be one method of concentrating the delivery of drugs or genes bound to microbubbles to selective areas of endothelial dysfunction. Ultrasound-mediated destruction of microbubbles may also be useful for targeted drug delivery and enhancing intravascular thrombolysis.

並列關鍵字

Myocardial contrast echocardiography ； Drug delivery ； Thrombolysis