ON-LINE MONITOR OF HEPATIC PERFUSION USING FLUORESCENCE

该项目的目的是展示一种新的光谱技术在术中和术后准确在线监测肝脏血流和氧合的有效性，并开发一种适合临床试验的原型系统。这项新技术使用激光诱导荧光衰减光谱(LIFAS)来在线获得可靠的组织缺血测量结果。初步的体内实验结果证明了该方法的可行性。一期工程的具体目标是：a)测定活体肝组织的荧光衰减光谱，b)确定血液灌注量减少对肝组织荧光衰减光谱的影响。在第二阶段，我们将建立一个从测量的衰减光谱中可靠地检测肝脏缺血的多变量模型，并将通过广泛的动物实验在体内证明其有效性。通过适当的适应，该技术可以应用于监测其他器官和组织的缺血。这项拟议的技术将能够在床边持续监测肝脏手术中和术后肝组织的灌注量和活性。目前，检测血液中的肝酶(转氨酶)和凝血因子(凝血酶原)是唯一可靠的检测与肝脏灌注相关的肝功能障碍的方法，但只有在严重的肝损伤已经发生后才能进行。建议的商业应用：完全开发和测试的肝血流灌注在线监测系统将对肝脏手术和移植的术中和术后监测有价值。同样的监测系统也可适用于其他器官(如肾脏和心脏)。

The objective of this project is the demonstration of the efficacy of a new spectroscopic technique for accurate intraoperative and postoperative on- line monitoring of liver perfusion and oxygenation and the development of a prototype system appropriate for clinical trials. This novel technology employs laser induced fluorescence attenuation spectroscopy (LIFAS) to derive reliable measurements of tissue ischemia on-line. Preliminary in- vivo experimental results have demonstrated the feasibility of this approach. The specific aims of the Phase I project are: a) determine the fluorescence attenuation spectrum of hepatic tissue in-vivo, b) determine the effects of reduced blood perfusion on the fluorescence attenuation spectrum of hepatic tissue. In Phase II, we will develop a multivariate model for the reliable detection of hepatic ischernia from measured attenuation spectra, and we will demonstrate its efficacy in-vivo through extensive animal experiments. Through proper adaptation, the technique can be applied for monitoring ischemia in other organs and tissues. The proposed technique will enable the continuous bedside monitoring of the perfusion and viability of hepatic tissue during and after liver surgery. Currently, the measurement of liver enzymes (transaminases) and clotting factors (prothrombin) in the blood is the only reliable means for detecting perfusion-related hepatic dysfunction, but only after significant liver damage has already occurred. PROPOSED COMMERCIAL APPLICATION: The fully developed and tested system for on-line monitoring of hepatic perfusion will be valuable for intraoperative and postoperative monitoring in liver surgery and transplantation. The same monitoring system can be adapted for other organs (e.g. kidney and heart).