Continuous Monitoring of Hepatic Function by Absorption Technique

Continuous Monitoring of Hepatic Function by Absorption Technique 

Until recently, previous studies for continuous monitoring of hepatic function with ICG utilized the absorption mode. However, new studies demonstrate that the highly sensitive fluorescence technique can equally be used [148-150]. In addition to high sensitivity, in-depth analysis of the emission, excitation and polarization properties of fluorescence spectroscopy furnishes additional functional information about the dye molecule. In this system, the fluorescence profile emanating from the clearance of injected biocompatible dye is monitored with a small photodetector. Fig. 8 shows the in vivo fluorescence detection apparatus developed for continuous monitoring of organ functions [147,148]. 

This approach assumes that the blood clearance profile of the dye follows an open one-compartment pharmacokinetics model. The characteristics of such a 

In a typical procedure, a continuous wave laser (50 mW) excites ICG at 780 nm and the fluorescence signal is captured at 830 nm. Subsequent to a bolus injection in the tail vein of the rat, the time-dependent clearance of ICG from plasma can be monitored in real-time as shown in Eig. 9 for three rat data sets. 

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